Protective efficacy of neuroactive steroids against cocaine kindled-seizures in mice.

Neuroactive steroids demonstrate pharmacological actions that have relevance for a host of neurological and psychiatric disorders. They offer protection against seizures in a range of models and seem to inhibit certain stages of drug dependence in preclinical assessments. The present study was designed to evaluate two endogenous and one synthetic neuroactive steroid that positively modulate the gamma-aminobutyric acid (GABA(A)) receptor against the increase in sensitivity to the convulsant effects of cocaine engendered by repeated cocaine administration (seizure kindling). Allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one), pregnanolone (3alpha-hydroxy-5beta-pregnan-20-one) and ganaxolone (a synthetic derivative of allopregnanolone 3alpha-hydroxy-3beta-methyl-5alpha-pregnan-20-one) were tested for their ability to suppress the expression (anticonvulsant effect) and development (antiepileptogenic effect) of cocaine-kindled seizures in male, Swiss-Webster mice. Kindled seizures were induced by daily administration of 60 mg/kg cocaine for 5 days. All of these positive GABA(A) modulators suppressed the expression of kindled seizures, whereas only allopregnanolone and ganaxolone inhibited the development of kindling. Allopregnanolone and pregnanolone, but not ganaxolone, also reduced cumulative lethality associated with kindling. These findings demonstrate that some neuroactive steroids attenuate convulsant and sensitizing properties of cocaine and add to a growing literature on their potential use in the modulation of effects of drugs of abuse.

steroids

cocaine

seizures

steroids

neurological and psychiatric disorders

neurological disorders

psychiatric disorders

seizures

drug dependence

steroid

gamma-aminobutyric acid

GABA

cocaine

cocaine

seizure

Allopregnanolone

pregnanolone

ganaxolone

allopregnanolone

cocaine

seizures

seizures

cocaine

GABA

seizures

allopregnanolone

ganaxolone

Allopregnanolone

pregnanolone

ganaxolone

steroids

cocaine


Kidney function and morphology after short-term combination therapy with cyclosporine A, tacrolimus and sirolimus in the rat.

BACKGROUND: Sirolimus (SRL) may supplement calcineurin inhibitors in clinical organ transplantation. These are nephrotoxic, but SRL seems to act differently displaying only minor nephrotoxic effects, although this question is still open. In a number of treatment protocols where SRL was combined with a calcineurin inhibitor indications of a synergistic nephrotoxic effect were described. The aim of this study was to examine further the renal function, including morphological analysis of the kidneys of male Sprague-Dawley rats treated with either cyclosporine A (CsA), tacrolimus (FK506) or SRL as monotherapies or in different combinations. METHODS: For a period of 2 weeks, CsA 15 mg/kg/day (given orally), FK506 3.0 mg/kg/day (given orally) or SRL 0.4 mg/kg/day (given intraperitoneally) was administered once a day as these doses have earlier been found to achieve a significant immunosuppressive effect in Sprague-Dawley rats. In the 'conscious catheterized rat' model, the glomerular filtration rate (GFR) was measured as the clearance of Cr(EDTA). The morphological analysis of the kidneys included a semi-quantitative scoring system analysing the degree of striped fibrosis, subcapsular fibrosis and the number of basophilic tubules, plus an additional stereological analysis of the total grade of fibrosis in the cortex stained with Sirius Red. RESULTS: CsA, FK506 and SRL all significantly decreased the GFR. A further deterioration was seen when CsA was combined with either FK506 or SRL, whereas the GFR remained unchanged in the group treated with FK506 plus SRL when compared with treatment with any of the single substances. The morphological changes presented a similar pattern. The semi-quantitative scoring was significantly worst in the group treated with CsA plus SRL (P<0.001 compared with controls) and the analysis of the total grade of fibrosis also showed the highest proportion in the same group and was significantly different from controls (P<0.02). The FK506 plus SRL combination showed only a marginally higher degree of fibrosis as compared with controls (P=0.05). CONCLUSION: This rat study demonstrated a synergistic nephrotoxic effect of CsA plus SRL, whereas FK506 plus SRL was better tolerated.

cyclosporine A

tacrolimus

sirolimus

Sirolimus

SRL

nephrotoxic

SRL

nephrotoxic

SRL

nephrotoxic

cyclosporine A

CsA

tacrolimus

SRL

CsA

SRL

fibrosis

fibrosis

fibrosis

CsA

SRL

CsA

SRL

SRL

CsA

SRL

fibrosis

SRL

fibrosis

nephrotoxic

CsA

SRL

SRL


Effect of fucoidan treatment on collagenase-induced intracerebral hemorrhage in rats.

Inflammatory cells are postulated to mediate some of the brain damage following ischemic stroke. Intracerebral hemorrhage is associated with more inflammation than ischemic stroke. We tested the sulfated polysaccharide fucoidan, which has been reported to reduce inflammatory brain damage, in a rat model of intracerebral hemorrhage induced by injection of bacterial collagenase into the caudate nucleus. Rats were treated with seven day intravenous infusion of fucoidan (30 micrograms h-1) or vehicle. The hematoma was assessed in vivo by magnetic resonance imaging. Motor behavior, passive avoidance, and skilled forelimb function were tested repeatedly for six weeks. Fucoidan-treated rats exhibited evidence of impaired blood clotting and hemodilution, had larger hematomas, and tended to have less inflammation in the vicinity of the hematoma after three days. They showed significantly more rapid improvement of motor function in the first week following hemorrhage and better memory retention in the passive avoidance test. Acute white matter edema and eventual neuronal loss in the striatum adjacent to the hematoma did not differ between the two groups. Investigation of more specific anti-inflammatory agents and hemodiluting agents are warranted in intracerebral hemorrhage.

fucoidan

intracerebral hemorrhage

brain damage

ischemic stroke

Intracerebral hemorrhage

inflammation

ischemic stroke

fucoidan

brain damage

intracerebral hemorrhage

fucoidan

hematoma

Fucoidan

impaired blood clotting

hemodilution

hematomas

inflammation

hematoma

hemorrhage

white matter edema

neuronal loss

hematoma

intracerebral hemorrhage


Paracetamol-associated coma, metabolic acidosis, renal and hepatic failure.

A case of metabolic acidosis, acute renal failure and hepatic failure following paracetamol ingestion is presented. The diagnostic difficulty at presentation is highlighted. Continuous arteriovenous haemofiltration proved a valuable means of maintaining fluid and electrolyte balance. The patient recovered.

Paracetamol

coma

metabolic acidosis

renal and hepatic failure

renal failure

hepatic failure

metabolic acidosis

acute renal failure and hepatic failure

acute renal failure

acute
hepatic failure

paracetamol


Hepatic reactions associated with ketoconazole in the United Kingdom.

Ketoconazole was introduced in the United Kingdom in 1981. By November 1984 the Committee on Safety of Medicines had received 82 reports of possible hepatotoxicity associated with the drug, including five deaths. An analysis of the 75 cases that had been adequately followed up suggested that 16, including three deaths, were probably related to treatment with the drug. Of the remainder, 48 were possibly related to treatment, five were unlikely to be so, and six were unclassifiable. The mean age of patients in the 16 probable cases was 57.9, with hepatotoxicity being more common in women. The average duration of treatment before the onset of jaundice was 61 days. None of these well validated cases occurred within the first 10 days after treatment. The results of serum liver function tests suggested hepatocellular injury in 10 (63%); the rest showed a mixed pattern. In contrast, the results of histological examination of the liver often showed evidence of cholestasis. The characteristics of the 48 patients in the possible cases were similar. Allergic manifestations such as rash and eosinophilia were rare. Hepatitis was usually reversible when treatment was stopped, with the results of liver function tests returning to normal after an average of 3.1 months. In two of the three deaths probably associated with ketoconazole treatment the drug had been continued after the onset of jaundice and other symptoms of hepatitis. Clinical and biochemical monitoring at regular intervals for evidence of hepatitis is advised during long term treatment with ketoconazole to prevent possible serious hepatic injury.

ketoconazole

Ketoconazole

hepatotoxicity

deaths

deaths

hepatotoxicity

jaundice

hepatocellular injury

cholestasis

rash

eosinophilia

Hepatitis

deaths

ketoconazole

jaundice

hepatitis

hepatitis

ketoconazole

hepatic injury


Combined effects of prolonged prostaglandin E1-induced hypotension and haemodilution on human hepatic function.

Combined effects of prolonged prostaglandin E1 (PGE1)-induced hypotension and haemodilution on hepatic function were studied in 30 patients undergoing hip surgery. The patients were randomly allocated to one of three groups; those in group A (n = 10) were subjected to controlled hypotension alone, those in group B (n = 10) to haemodilution alone and those in group C (n = 10) to both controlled hypotension and haemodilution. Haemodilution in groups B and C was produced by withdrawing approximately 1000 mL of blood and replacing it with the same amount of dextran solution, and final haematocrit values were 21 or 22%. Controlled hypotension in groups A and C was induced with PGE1 to maintain mean arterial blood pressure at 55 mmHg for 180 min. Measurements included arterial ketone body ratio (AKBR, aceto-acetate/3-hydroxybutyrate) and clinical hepatic function parameters. AKBR and biological hepatic function tests showed no change throughout the time course in groups A and B. In group C, AKBR showed a significant decrease at 120 min (-40%) and at 180 min (-49%) after the start of hypotension and at 60 min (-32%) after recovery of normotension, and SGOT, SGPT, LDH and total bilirubin showed significant increases after operation. The results suggest that a prolonged combination of more than 120 min of PGE1-induced hypotension and moderate haemodilution would cause impairment of hepatic function.

prostaglandin E1

hypotension

haemodilution

prostaglandin E1

hypotension

haemodilution

hypotension

haemodilution

hypotension

haemodilution

Haemodilution

dextran

hypotension

aceto-acetate

hypotension

bilirubin

hypotension

haemodilution

impairment of hepatic function


Levodopa-induced dyskinesias in patients with Parkinson's disease: filling the bench-to-bedside gap.

Levodopa is the most effective drug for the treatment of Parkinson's disease. However, the long-term use of this dopamine precursor is complicated by highly disabling fluctuations and dyskinesias. Although preclinical and clinical findings suggest pulsatile stimulation of striatal postsynaptic receptors as a key mechanism underlying levodopa-induced dyskinesias, their pathogenesis is still unclear. In recent years, evidence from animal models of Parkinson's disease has provided important information to understand the effect of specific receptor and post-receptor molecular mechanisms underlying the development of dyskinetic movements. Recent preclinical and clinical data from promising lines of research focus on the differential role of presynaptic versus postsynaptic mechanisms, dopamine receptor subtypes, ionotropic and metabotropic glutamate receptors, and non-dopaminergic neurotransmitter systems in the pathophysiology of levodopa-induced dyskinesias.

Levodopa

dyskinesias

Parkinson's disease

Levodopa

Parkinson's disease

dopamine

dyskinesias

levodopa

dyskinesias

Parkinson's disease

dyskinetic movements

dopamine

glutamate

levodopa

dyskinesias


Prevention of seizures and reorganization of hippocampal functions by transplantation of bone marrow cells in the acute phase of experimental epilepsy.

In this study, we investigated the therapeutic potential of bone marrow mononuclear cells (BMCs) in a model of epilepsy induced by pilocarpine in rats. BMCs obtained from green fluorescent protein (GFP) transgenic mice or rats were transplanted intravenously after induction of status epilepticus (SE). Spontaneous recurrent seizures (SRS) were monitored using Racine's seizure severity scale. All of the rats in the saline-treated epileptic control group developed SRS, whereas none of the BMC-treated epileptic animals had seizures in the short term (15 days after transplantation), regardless of the BMC source. Over the long-term chronic phase (120 days after transplantation), only 25% of BMC-treated epileptic animals had seizures, but with a lower frequency and duration compared to the epileptic control group. The density of hippocampal neurons in the brains of animals treated with BMCs was markedly preserved. At hippocampal Schaeffer collateral-CA1 synapses, long-term potentiation was preserved in BMC-transplanted rats compared to epileptic controls. The donor-derived GFP(+) cells were rarely found in the brains of transplanted epileptic rats. In conclusion, treatment with BMCs can prevent the development of chronic seizures, reduce neuronal loss, and influence the reorganization of the hippocampal neuronal network.

seizures

epilepsy

epilepsy

pilocarpine

status epilepticus

SE

Spontaneous recurrent seizures

SRS

seizure

epileptic

SRS

epileptic

seizures

epileptic

seizures

epileptic

epileptic

epileptic

seizures

neuronal loss


Cardioprotective effect of salvianolic acid A on isoproterenol-induced myocardial infarction in rats.

The present study was designed to evaluate the cardioprotective potential of salvianolic acid A on isoproterenol-induced myocardial infarction in rats. Hemodynamic parameters and lead II electrocardiograph were monitored and recorded continuously. Cardiac marker enzymes and antioxidative parameters in serum and heart tissues were measured. Assay for mitochondrial respiratory function and histopathological examination of heart tissues were performed. Isoproterenol-treated rats showed significant increases in the levels of lactate dehydrogenase, aspartate transaminase, creatine kinase and malondialdehyde and significant decreases in the activities of superoxide dismutase, catalase and glutathione peroxidase in serum and heart. These rats also showed declines in left ventricular systolic pressure, maximum and minimum rate of developed left ventricular pressure, and elevation of left ventricular end-diastolic pressure and ST-segment. In addition, mitochondrial respiratory dysfunction characterized by decreased respiratory control ratio and ADP/O was observed in isoproterenol-treated rats. Administration of salvianolic acid A for a period of 8 days significantly attenuated isoproterenol-induced cardiac dysfunction and myocardial injury and improved mitochondrial respiratory function. The protective role of salvianolic acid A against isoproterenol-induced myocardial damage was further confirmed by histopathological examination. The results of our study suggest that salvianolic acid A possessing antioxidant activity has a significant protective effect against isoproterenol-induced myocardial infarction.

salvianolic acid A

isoproterenol

myocardial infarction

salvianolic acid A

isoproterenol

myocardial infarction

Isoproterenol

lactate

aspartate

creatine

malondialdehyde

superoxide

glutathione

respiratory dysfunction

ADP

isoproterenol

salvianolic acid A

isoproterenol

cardiac dysfunction

myocardial injury

salvianolic acid A

isoproterenol

myocardial damage

salvianolic acid A

isoproterenol

myocardial infarction


Acute effects of N-(2-propylpentanoyl)urea on hippocampal amino acid neurotransmitters in pilocarpine-induced seizure in rats.

The present study aimed to investigate the anticonvulsant activity as well as the effects on the level of hippocampal amino acid neurotransmitters (glutamate, aspartate, glycine and GABA) of N-(2-propylpentanoyl)urea (VPU) in comparison to its parent compound, valproic acid (VPA). VPU was more potent than VPA, exhibiting the median effective dose (ED(50)) of 49 mg/kg in protecting rats against pilocarpine-induced seizure whereas the corresponding value for VPA was 322 mg/kg. In vivo microdialysis demonstrated that an intraperitoneal administration of pilocarpine induced a pronounced increment of hippocampal glutamate and aspartate whereas no significant change was observed on the level of glycine and GABA. Pretreatment with either VPU (50 and 100 mg/kg) or VPA (300 and 600 mg/kg) completely abolished pilocarpine-evoked increases in extracellular glutamate and aspartate. In addition, a statistically significant reduction was also observed on the level of GABA and glycine but less than a drastic reduction of glutamate and aspartate level. Based on the finding that VPU and VPA could protect the animals against pilocarpine-induced seizure it is suggested that the reduction of inhibitory amino acid neurotransmitters was comparatively minor and offset by a pronounced reduction of glutamate and aspartate. Therefore, like VPA, the finding that VPU could drastically reduce pilocarpine-induced increases in glutamate and aspartate should account, at least partly, for its anticonvulsant activity observed in pilocarpine-induced seizure in experimental animals. Some other mechanism than those being reported herein should be further investigated.

amino acid

pilocarpine

seizure

amino acid

glutamate

aspartate

glycine

GABA

VPU

valproic acid

VPA

VPU

VPA

pilocarpine

seizure

VPA

pilocarpine

glutamate

aspartate

glycine

GABA

VPU

VPA

pilocarpine

glutamate

aspartate

GABA

glycine

glutamate

aspartate

VPU

VPA

pilocarpine

seizure

amino acid

glutamate

aspartate

VPA

VPU

pilocarpine

glutamate

aspartate

pilocarpine

seizure


Acute hepatitis attack after exposure to telithromycin.

INTRODUCTION: Antibiotic-associated hepatotoxicity is rare. With widespread use of antimicrobial agents, however, hepatic injury occurs frequently, and among adverse drug reactions, idiosyncratic reactions are the most serious. CASE SUMMARY: A 25-year-old male patient, with a height of 175 cm and weight of 72 kg presented to Marmara University Hospital Emergency Department, Istanbul, Turkey, with 5 days' history of jaundice, malaise, nausea, and vomiting. He had been prescribed telithromycin 400 mg/d PO to treat an upper respiratory tract infection 7 days prior. Admission laboratory tests were as follows: alanine aminotransferase, 67 U/L (reference range, 10-37 U/L); aspartate aminotransferase, 98 U/L (10-40 U/L); alkaline phosphatase, 513 U/L (0-270 U/L); gamma-glutamyltransferase, 32 U/L (7-49 U/L); amylase, 46 U/L (0-220 U/L); total bilirubin, 20.1 mg/dL (0.2-1.0 mg/dL); direct bilirubin, 14.8 mg/dL (0-0.3 mg/dL); and albumin, 4.7 mg/dL (3.5-5.4 mg/dL). No toxin, alcohol, or other drugs were reported. The patient had suffered a previous episode of "acute hepatitis of unknown origin," that occurred after telithromycin usage. Both incidents occurred within a year. DISCUSSION: Telithromycin is the first of the ketolide antibacterials to receive US Food and Drug Administration approval for clinical use. It has been associated with infrequent and usually reversible severe hepatic dysfunction. Based on a score of 8 on the Naranjo adverse drug reaction probability scale, telithromycin was the probable cause of acute hepatitis in this patient, and pathological findings suggested drug-induced toxic hepatitis. Recurrence of hepatitis attack might have been avoided if the initial incident had been communicated to the attending physician who prescribed telithromycin the second time. CONCLUSION: Here we report a case of acute hepatitis probably associated with the administration of telithromycin.

hepatitis

telithromycin

hepatotoxicity

hepatic injury

adverse drug reactions

jaundice

nausea

vomiting

telithromycin

upper respiratory tract infection

alanine

aspartate

bilirubin

bilirubin

alcohol

hepatitis

telithromycin

Telithromycin

hepatic dysfunction

adverse drug reaction

telithromycin

hepatitis

toxic hepatitis

hepatitis

telithromycin

hepatitis

telithromycin


Spironolactone-induced renal insufficiency and hyperkalemia in patients with heart failure.

BACKGROUND: A previous randomized controlled trial evaluating the use of spironolactone in heart failure patients reported a low risk of hyperkalemia (2%) and renal insufficiency (0%). Because treatments for heart failure have changed since the benefits of spironolactone were reported, the prevalence of these complications may differ in current clinical practice. We therefore sought to determine the prevalence and clinical associations of hyperkalemia and renal insufficiency in heart failure patients treated with spironolactone. METHODS: We performed a case control study of heart failure patients treated with spironolactone in our clinical practice. Cases were patients who developed hyperkalemia (K(+) >5.0 mEq/L) or renal insufficiency (Cr >or=2.5 mg/dL), and they were compared to 2 randomly selected controls per case. Clinical characteristics, medications, and serum chemistries at baseline and follow-up time periods were compared. RESULTS: Sixty-seven of 926 patients (7.2%) required discontinuation of spironolactone due to hyperkalemia (n = 33) or renal failure (n = 34). Patients who developed hyperkalemia were older and more likely to have diabetes, had higher baseline serum potassium levels and lower baseline potassium supplement doses, and were more likely to be treated with beta-blockers than controls (n = 134). Patients who developed renal insufficiency had lower baseline body weight and higher baseline serum creatinine, required higher doses of loop diuretics, and were more likely to be treated with thiazide diuretics than controls. CONCLUSIONS: Spironolactone-induced hyperkalemia and renal insufficiency are more common in our clinical experience than reported previously. This difference is explained by patient comorbidities and more frequent use of beta-blockers.

Spironolactone

renal insufficiency

hyperkalemia

heart failure

spironolactone

heart failure

hyperkalemia

renal insufficiency

heart failure

spironolactone

hyperkalemia

renal insufficiency

heart failure

spironolactone

heart failure

spironolactone

hyperkalemia

K

renal insufficiency

Cr

spironolactone

hyperkalemia

renal failure

hyperkalemia

diabetes

potassium

potassium

renal insufficiency

creatinine

thiazide

Spironolactone

hyperkalemia

renal insufficiency


End-stage renal disease (ESRD) after orthotopic liver transplantation (OLTX) using calcineurin-based immunotherapy: risk of development and treatment.

BACKGROUND: The calcineurin inhibitors cyclosporine and tacrolimus are both known to be nephrotoxic. Their use in orthotopic liver transplantation (OLTX) has dramatically improved success rates. Recently, however, we have had an increase of patients who are presenting after OLTX with end-stage renal disease (ESRD). This retrospective study examines the incidence and treatment of ESRD and chronic renal failure (CRF) in OLTX patients. METHODS: Patients receiving an OLTX only from June 1985 through December of 1994 who survived 6 months postoperatively were studied (n=834). Our prospectively collected database was the source of information. Patients were divided into three groups: Controls, no CRF or ESRD, n=748; CRF, sustained serum creatinine >2.5 mg/dl, n=41; and ESRD, n=45. Groups were compared for preoperative laboratory variables, diagnosis, postoperative variables, survival, type of ESRD therapy, and survival from onset of ESRD. RESULTS: At 13 years after OLTX, the incidence of severe renal dysfunction was 18.1% (CRF 8.6% and ESRD 9.5%). Compared with control patients, CRF and ESRD patients had higher preoperative serum creatinine levels, a greater percentage of patients with hepatorenal syndrome, higher percentage requirement for dialysis in the first 3 months postoperatively, and a higher 1-year serum creatinine. Multivariate stepwise logistic regression analysis using preoperative and postoperative variables identified that an increase of serum creatinine compared with average at 1 year, 3 months, and 4 weeks postoperatively were independent risk factors for the development of CRF or ESRD with odds ratios of 2.6, 2.2, and 1.6, respectively. Overall survival from the time of OLTX was not significantly different among groups, but by year 13, the survival of the patients who had ESRD was only 28.2% compared with 54.6% in the control group. Patients developing ESRD had a 6-year survival after onset of ESRD of 27% for the patients receiving hemodialysis versus 71.4% for the patients developing ESRD who subsequently received kidney transplants. CONCLUSIONS: Patients who are more than 10 years post-OLTX have CRF and ESRD at a high rate. The development of ESRD decreases survival, particularly in those patients treated with dialysis only. Patients who develop ESRD have a higher preoperative and 1-year serum creatinine and are more likely to have hepatorenal syndrome. However, an increase of serum creatinine at various times postoperatively is more predictive of the development of CRF or ESRD. New strategies for long-term immunosuppression may be needed to decrease this complication.

End-stage renal disease

ESRD

cyclosporine

tacrolimus

nephrotoxic

end-stage renal disease

ESRD

ESRD

chronic renal failure

CRF

CRF

ESRD

CRF

creatinine

ESRD

ESRD

ESRD

renal dysfunction

CRF

ESRD

CRF

ESRD

creatinine

hepatorenal syndrome

creatinine

creatinine

CRF

ESRD

ESRD

ESRD

ESRD

ESRD

CRF

ESRD

ESRD

ESRD

creatinine

hepatorenal syndrome

creatinine

CRF

ESRD


Effect of intravenous nimodipine on blood pressure and outcome after acute stroke.

BACKGROUND AND PURPOSE: The Intravenous Nimodipine West European Stroke Trial (INWEST) found a correlation between nimodipine-induced reduction in blood pressure (BP) and an unfavorable outcome in acute stroke. We sought to confirm this correlation with and without adjustment for prognostic variables and to investigate outcome in subgroups with increasing levels of BP reduction. METHODS: Patients with a clinical diagnosis of ischemic stroke (within 24 hours) were consecutively allocated to receive placebo (n=100), 1 mg/h (low-dose) nimodipine (n=101), or 2 mg/h (high-dose) nimodipine (n=94). The correlation between average BP change during the first 2 days and the outcome at day 21 was analyzed. RESULTS: Two hundred sixty-five patients were included in this analysis (n=92, 93, and 80 for placebo, low dose, and high dose, respectively). Nimodipine treatment resulted in a statistically significant reduction in systolic BP (SBP) and diastolic BP (DBP) from baseline compared with placebo during the first few days. In multivariate analysis, a significant correlation between DBP reduction and worsening of the neurological score was found for the high-dose group (beta=0.49, P=0. 048). Patients with a DBP reduction of > or =20% in the high-dose group had a significantly increased adjusted OR for the compound outcome variable death or dependency (Barthel Index <60) (n/N=25/26, OR 10. 16, 95% CI 1.02 to 101.74) and death alone (n/N=9/26, OR 4.336, 95% CI 1.131 16.619) compared with all placebo patients (n/N=62/92 and 14/92, respectively). There was no correlation between SBP change and outcome. CONCLUSIONS: DBP, but not SBP, reduction was associated with neurological worsening after the intravenous administration of high-dose nimodipine after acute stroke. For low-dose nimodipine, the results were not conclusive. These results do not confirm or exclude a neuroprotective property of nimodipine.

nimodipine

acute stroke

Nimodipine

Stroke

nimodipine

reduction in blood pressure

acute stroke

BP reduction

ischemic stroke

nimodipine

nimodipine

Nimodipine

reduction in systolic BP

DBP reduction

DBP reduction

death

death

nimodipine

acute stroke

nimodipine

nimodipine


Transient neurologic symptoms after spinal anesthesia: a lower incidence with prilocaine and bupivacaine than with lidocaine.

BACKGROUND: Recent evidence suggests that transient neurologic symptoms (TNSs) frequently follow lidocaine spinal anesthesia but are infrequent with bupivacaine. However, identification of a short-acting local anesthetic to substitute for lidocaine for brief surgical procedures remains an important goal. Prilocaine is an amide local anesthetic with a duration of action similar to that of lidocaine. Accordingly, the present, prospective double-blind study compares prilocaine with lidocaine and bupivacaine with respect to duration of action and relative risk of TNSs. METHODS: Ninety patients classified as American Society of Anesthesiologists physical status I or II who were scheduled for short gynecologic procedures under spinal anesthesia were randomly allocated to receive 2.5 ml 2% lidocaine in 7.5% glucose, 2% prilocaine in 7.5% glucose, or 0.5% bupivacaine in 7.5% glucose. All solutions were provided in blinded vials by the hospital pharmacy. Details of spinal puncture, extension and regression of spinal block, and the times to reach discharge criteria were noted. In the evening of postoperative day 1, patients were evaluated for TNSs by a physician unaware of the drug administered and the details of the anesthetic procedure. RESULTS: Nine of 30 patients receiving lidocaine experienced TNSs, 1 of 30 patients receiving prilocaine (P = 0.03) had them, and none of 30 patients receiving bupivacaine had TNSs. Times to ambulate and to void were similar after lidocaine and prilocaine (150 vs. 165 min and 238 vs. 253 min, respectively) but prolonged after bupivacaine (200 and 299 min, respectively; P < 0.05). CONCLUSIONS: Prilocaine may be preferable to lidocaine for short surgical procedures because it has a similar duration of action but a lower incidence of TNSs.

Transient neurologic symptoms

prilocaine

bupivacaine

lidocaine

transient neurologic symptoms

TNSs

lidocaine

bupivacaine

lidocaine

Prilocaine

lidocaine

prilocaine

lidocaine

bupivacaine

TNSs

lidocaine

glucose

prilocaine

glucose

bupivacaine

glucose

TNSs

lidocaine

TNSs

prilocaine

bupivacaine

TNSs

lidocaine

prilocaine

bupivacaine

Prilocaine

lidocaine

TNSs


The role of nicotine in smoking-related cardiovascular disease.

Nicotine activates the sympathetic nervous system and in this way could contribute to cardiovascular disease. Animal studies and mechanistic studies indicate that nicotine could play a role in accelerating atherosclerosis, but evidence among humans is too inadequate to be definitive about such an effect. Almost certainly, nicotine via its hemodynamic effects contributes to acute cardiovascular events, although current evidence suggests that the effects of nicotine are much less important than are the prothrombotic effects of cigarette smoking or the effects of carbon monoxide. Nicotine does not appear to enhance thrombosis among humans. Clinical studies of pipe smokers and people using transdermal nicotine support the idea that toxins other than nicotine are the most important causes of acute cardiovascular events. Finally, the dose response for cardiovascular events of nicotine appears to be flat, suggesting that if nicotine is involved, adverse effects might be seen with relatively low-level cigarette exposures.

nicotine

cardiovascular disease

Nicotine

cardiovascular disease

nicotine

atherosclerosis

nicotine

nicotine

carbon monoxide

Nicotine

thrombosis

nicotine

nicotine

nicotine

nicotine


Seizure resulting from a venlafaxine overdose.

OBJECTIVE: To report a case of venlafaxine overdose. CASE SUMMARY: A 40-year-old woman with major depression took an overdose of venlafaxine in an apparent suicide attempt. After the ingestion of 26 venlafaxine 50-mg tablets, the patient experienced a witnessed generalized seizure. She was admitted to the medical intensive care unit, venlafaxine was discontinued, and no further sequelae were seen. DISCUSSION: To our knowledge, this is the first reported case of venlafaxine overdose that resulted in a generalized seizure. Based on nonoverdose pharmacokinetics and pharmacodynamics of venlafaxine and the potential risks of available interventions, no emergent therapy was instituted. CONCLUSIONS: The venlafaxine overdose in our patient resulted in a single episode of generalized seizure but elicited no further sequelae.

Seizure

venlafaxine

overdose

venlafaxine

overdose

major depression

overdose

venlafaxine

venlafaxine

seizure

venlafaxine

venlafaxine

overdose

seizure

venlafaxine

venlafaxine

overdose

seizure


Effect of nifedipine on renal function in liver transplant recipients receiving tacrolimus.

The effect of nifedipine on renal function in liver transplant recipients who were receiving tacrolimus was evaluated between January 1992 and January 1996. Two groups of patients receiving tacrolimus were compared over a period of 1 year, one group comprising hypertensive patients who were receiving nifedipine, and the other comprising nonhypertensive patients not receiving nifedipine. The time from transplant to baseline was similar in all patients. Nifedipine significantly improved kidney function as indicated by a significant lowering of serum creatinine levels at 6 and 12 months. The observed positive impact of nifedipine on reducing the nephrotoxicity associated with tacrolimus in liver transplant recipients should be an important factor in selecting an agent to treat hypertension in this population.

nifedipine

tacrolimus

nifedipine

tacrolimus

tacrolimus

hypertensive

nifedipine

nifedipine

Nifedipine

creatinine

nifedipine

nephrotoxicity

tacrolimus

hypertension


Sinus arrest associated with continuous-infusion cimetidine.

The administration of intermittent intravenous infusions of cimetidine is infrequently associated with the development of bradyarrhythmias. A 40-year-old man with leukemia and no history of cardiac disease developed recurrent, brief episodes of apparent sinus arrest while receiving continuous-infusion cimetidine 50 mg/hour. The arrhythmias were temporally related to cimetidine administration, disappeared after dechallenge, and did not recur during ranitidine treatment. This is the first reported case of sinus arrest associated with continuous-infusion cimetidine.

Sinus arrest

cimetidine

cimetidine

bradyarrhythmias

leukemia

cardiac disease

sinus arrest

cimetidine

arrhythmias

cimetidine

ranitidine

sinus arrest

cimetidine


Composition of gall bladder stones associated with octreotide: response to oral ursodeoxycholic acid.

Octreotide, an effective treatment for acromegaly, induces gall bladder stones in 13-60% of patients. Because knowledge of stone composition is essential for studies of their pathogenesis, treatment, and prevention, this was investigated by direct and indirect methods in 14 octreotide treated acromegalic patients with gall stones. Chemical analysis of gall stones retrieved at cholecystectomy from two patients, showed that they contained 71% and 87% cholesterol by weight. In the remaining 12 patients, localised computed tomography of the gall bladder showed that eight had stones with maximum attenuation scores of < 100 Hounsfield units (values of < 100 HU predict cholesterol rich, dissolvable stones). Gall bladder bile was obtained by ultrasound guided, fine needle puncture from six patients. All six patients had supersaturated bile (mean (SEM) cholesterol saturation index of 1.19 (0.08) (range 1.01-1.53)) and all had abnormally rapid cholesterol microcrystal nucleation times (< 4 days (range 1-4)), whilst in four, the bile contained cholesterol microcrystals immediately after sampling. Of the 12 patients considered for oral ursodeoxycholic acid (UDCA) treatment, two had a blocked cystic duct and were not started on UDCA while one was lost to follow up. After one year of treatment, five of the remaining nine patients showed either partial (n = 3) or complete (n = 2) gall stone dissolution, suggesting that their stones were cholesterol rich. This corresponds, by actuarial (life table) analysis, to a combined gall stone dissolution rate of 58.3 (15.9%). In conclusion, octreotide induced gall stones are generally small, multiple, and cholesterol rich although, in common with spontaneous gall stone disease, at presentation some patients will have a blocked cystic duct and some gall stones containing calcium.

gall bladder stones

octreotide

ursodeoxycholic acid

Octreotide

acromegaly

gall bladder stones

octreotide

acromegalic

gall stones

gall stones

cholesterol

cholesterol

cholesterol

cholesterol

cholesterol

ursodeoxycholic acid

UDCA

UDCA

gall stone

cholesterol

gall stone

octreotide

gall stones

cholesterol

gall stone disease

gall stones

calcium


Cardiovascular complications associated with terbutaline treatment for preterm labor.

Severe cardiovascular complications occurred in eight of 160 patients treated with terbutaline for preterm labor. Associated corticosteroid therapy and twin gestations appear to be predisposing factors. Potential mechanisms of the pathophysiology are briefly discussed.

Cardiovascular complications

terbutaline

preterm labor

cardiovascular complications

terbutaline

preterm labor


Neurologic effects of subarachnoid administration of 2-chloroprocaine-CE, bupivacaine, and low pH normal saline in dogs.

The purpose of this study was to evaluate the neurologic consequences of deliberate subarachnoid injection of large volumes of 2-chloroprocaine-CE in experimental animals. The possible role of low pH as well as total volume as potential factors in causing neurotoxicity was evaluated. The 65 dogs in the study received injections in the subarachnoid space as follows: 6 to 8 ml of bupivacaine (N = 15), 2-chloroprocaine-CE (N = 20), low pH normal saline (pH 3.0) (N = 20), or normal saline (N = 10). Of the 20 animals that received subarachnoid injection of 2-chloroprocaine-CE seven (35%) developed hind-limb paralysis. None of the animals that received bupivacaine, normal saline, or normal saline titrated to a pH 3.0 developed hind-limb paralysis. Of the 15 spinal cords of the animals that received 2-chloroprocaine-CE, 13 showed subpial necrosis; the nerve roots and subarachnoid vessels were normal. The spinal cords of the animals that received bupivacaine, low pH normal saline (pH 3.0), or normal saline did not show abnormal findings.

bupivacaine

neurotoxicity

bupivacaine

paralysis

bupivacaine

paralysis

subpial necrosis

bupivacaine


Early adjuvant adriamycin in superficial bladder carcinoma.

A multicenter study was performed in 110 patients with superficial transitional cell carcinoma of the bladder. Adriamycin (50 mg/50 ml) was administered intravesically within 24 h after transurethral resection of TA-T1 (O-A) bladder tumors. Instillation was repeated twice during the first week, then weekly during the first month and afterwards monthly for 1 year. The tolerance was evaluated in these 110 patients, and 29 patients presented with local side-effects. In 24 of these patients chemical cystitis was severe enough for them to drop out of the study. No systemic side-effects were observed. Recurrence was studied in 82 evaluable patients after 1 year of follow-up and in 72 patients followed for 2-3 years (mean 32 months). Of the 82 patients studied after 1 year, 23 had primary and 59 recurrent disease. Of the 82 evaluable patients, 50 did not show any recurrence after 1 year (61%), while 32 presented with one or more recurrences (39%). Of these recurrences, 27 were T1 tumors while five progressed to more highly invasive lesions. In patients that were free of recurrence during the first year, 80% remained tumor-free during the 2- to 3-year follow-up period. Of the patients developing one or more recurrences during the first year, only 50% presented with further recurrence once the instillations were stopped. The beneficial effect of Adriamycin appears obvious and might be related to the drug itself, the early and repeated instillations after TUR, or both.

adriamycin

bladder carcinoma

bladder carcinoma

carcinoma

carcinoma of the bladder

carcinoma of the bladder

carcinoma

Adriamycin

bladder tumors

cystitis

tumors

tumor

Adriamycin


Hyperkalemia associated with sulindac therapy.

Hyperkalemia has recently been recognized as a complication of nonsteroidal antiinflammatory agents (NSAID) such as indomethacin. Several recent studies have stressed the renal sparing features of sulindac, owing to its lack of interference with renal prostacyclin synthesis. We describe 4 patients in whom hyperkalemia ranging from 6.1 to 6.9 mEq/l developed within 3 to 8 days of sulindac administration. In all of them normal serum potassium levels reached within 2 to 4 days of stopping sulindac. As no other medications known to effect serum potassium had been given concomitantly, this course of events is suggestive of a cause-and-effect relationship between sulindac and hyperkalemia. These observations indicate that initial hopes that sulindac may not be associated with the adverse renal effects of other NSAID are probably not justified.

Hyperkalemia

sulindac

Hyperkalemia

indomethacin

sulindac

prostacyclin

hyperkalemia

sulindac

potassium

sulindac

potassium

sulindac

hyperkalemia

sulindac


Ventricular tachyarrhythmias during cesarean section after ritodrine therapy: interaction with anesthetics.

This case illustrates that patients receiving ritodrine for preterm labor may risk interactions between the residual betamimetic effects of ritodrine and the effects of anesthetics during cesarean section. Such interactions may result in serious cardiovascular complications even after cessation of an infusion of ritodrine. Preoperative assessment should focus on cardiovascular status and serum potassium level. Delaying induction of anesthesia should be considered whenever possible. Careful fluid administration and cautious use of titrated doses of ephedrine are advised. After delivery of the infant, there should be no contraindication to the use of an alpha-adrenergic vasopressor such as phenylephrine to treat hypotensive patients with tachycardia.

Ventricular tachyarrhythmias

ritodrine

ritodrine

preterm labor

ritodrine

cardiovascular complications

ritodrine

potassium

ephedrine

phenylephrine

hypotensive

tachycardia


Immunohistochemical, electron microscopic and morphometric studies of estrogen-induced rat prolactinomas after bromocriptine treatment.

To clarify the effects of bromocriptine on prolactinoma cells in vivo, immunohistochemical, ultrastructural and morphometrical analyses were applied to estrogen-induced rat prolactinoma cells 1 h and 6 h after injection of bromocriptine (3 mg/kg of body weight). One h after treatment, serum prolactin levels decreased markedly. Electron microscopy disclosed many secretory granules, slightly distorted rough endoplasmic reticulum, and partially dilated Golgi cisternae in the prolactinoma cells. Morphometric analysis revealed that the volume density of secretory granules increased, while the volume density of cytoplasmic microtubules decreased. These findings suggest that lowered serum prolactin levels in the early phase of bromocriptine treatment may result from an impaired secretion of prolactin due to decreasing numbers of cytoplasmic microtubules. At 6 h after injection, serum prolactin levels were still considerably lower than in controls. The prolactinoma cells at this time were well granulated, with vesiculated rough endoplasmic reticulum and markedly dilated Golgi cisternae. Electron microscopical immunohistochemistry revealed positive reaction products noted on the secretory granules, Golgi cisternae, and endoplasmic reticulum of the untreated rat prolactinoma cells. However, only secretory granules showed the positive reaction products for prolactin 6 h after bromocriptine treatment of the adenoma cells. An increase in the volume density of secretory granules and a decrease in the volume densities of rough endoplasmic reticulum and microtubules was determined by morphometric analysis, suggesting that bromocriptine inhibits protein synthesis as well as bringing about a disturbance of the prolactin secretion.

estrogen

prolactinomas

bromocriptine

bromocriptine

prolactinoma

estrogen

prolactinoma

bromocriptine

prolactinoma

bromocriptine

prolactinoma

prolactinoma

bromocriptine

adenoma

bromocriptine


On two paradoxical side-effects of prednisolone in rats, ribosomal RNA biosyntheses, and a mechanism of action.

Liver enlargement and muscle wastage occurred in Wistar rats following the subcutaneous administration of prednisolone. In the liver both the content of RNA and the biosynthesis of ribosomal RNA increased while both the RNA content and ribosomal RNA biosynthesis were reduced in the gastrocnemius muscle. It is suggested that the drug acted in a selective and tissue-specific manner to enhance ribosomal RNA synthesis in the liver and depress such synthesis in the muscle. This view supports the contention that the liver and muscle are independent sites of prednisolone action.

prednisolone

Liver enlargement

muscle wastage

prednisolone

prednisolone


Possible intramuscular midazolam-associated cardiorespiratory arrest and death.

Midazolam hydrochloride is commonly used for dental or endoscopic procedures. Although generally consisted safe when given intramuscularly, intravenous administration is known to cause respiratory and cardiovascular depression. This report describes the first published case of cardiorespiratory arrest and death associated with intramuscular administration of midazolam. Information regarding midazolam use is reviewed to provide recommendation for safe administration.

midazolam

cardiorespiratory arrest

death

Midazolam hydrochloride

respiratory depression

cardiovascular depression

cardiorespiratory arrest

death

midazolam

midazolam


Serial epilepsy caused by levodopa/carbidopa administration in two patients on hemodialysis.

Two patients with similar clinical features are presented: both patients had chronic renal failure, on hemodialysis for many years but recently begun on a high-flux dialyzer; both had been receiving a carbidopa/levodopa preparation; and both had the onset of hallucinosis and recurrent seizures, which were refractory to anticonvulsants. The first patient died without a diagnosis; the second patient had a dramatic recovery following the administration of vitamin B6. Neither patient was considered to have a renal state sufficiently severe enough to explain their presentation.

epilepsy

levodopa/carbidopa

chronic renal failure

carbidopa/levodopa

hallucinosis

seizures

vitamin B6


Effect of L-alpha-glyceryl-phosphorylcholine on amnesia caused by scopolamine.

The present study was carried out to test the effects of L-alpha-glycerylphosphorylcholine (L-alpha-GFC) on memory impairment induced by scopolamine in man. Thirty-two healthy young volunteers were randomly allocated to four different groups. They were given a ten day pretreatment with either L-alpha-GFC or placebo, p.o., and on the eleventh day either scopolamine or placebo, i.m. Before and 0.5, 1, 2, 3, and 6 h after injection the subjects were given attention and mnemonic tests. The findings of this study indicate that the drug is able to antagonize impairment of attention and memory induced by scopolamine.

L-alpha-glyceryl-phosphorylcholine

amnesia

scopolamine

L-alpha-glycerylphosphorylcholine

L-alpha-GFC

memory impairment

scopolamine

L-alpha-GFC

scopolamine

impairment of attention and memory

scopolamine


Seizures induced by the cocaine metabolite benzoylecgonine in rats.

The half-life (t1/2) of cocaine is relatively short, but some of the consequences of its use, such as seizures and strokes, can occur hours after exposure. This led us to hypothesize that a metabolite of cocaine may be responsible for some of those delayed sequelae. We evaluated the potential of the major metabolite of cocaine, benzoylecgonine (BE), to cause seizures. Two separate equimolar doses (0.2 and 0.4 mumol) of either cocaine or BE were injected ventricularly in unanesthetized juvenile rats. Treated rats were then evaluated for incidence, latency, and seizure pattern or for locomotor activity in animals without seizures. BE-Induced seizures occurred more frequently and had significantly longer latencies than those induced by equimolar amounts of cocaine. Whereas cocaine-induced seizures were best characterized as brief, generalized, and tonic and resulted in death, those induced by BE were prolonged, often multiple and mixed in type, and rarely resulted in death. Electrical recordings from the hippocampus showed a rhythmic progression in EEG frequency and voltage with clinical seizure expression. BE-Injected rats that did not have seizures had significantly more locomotor activity than cocaine-injected animals without seizures. The finding that cocaine- and BE-induced seizures differ in several respects suggests more than one mechanism for cocaine-induced seizures and emphasizes the importance of a cocaine metabolite, BE.

Seizures

cocaine

benzoylecgonine

cocaine

seizures

strokes

cocaine

cocaine

benzoylecgonine

BE

seizures

cocaine

BE

seizure

seizures

BE

seizures

cocaine

cocaine

seizures

death

BE

death

seizure

BE

seizures

cocaine

seizures

cocaine

BE

seizures

cocaine

seizures

cocaine

BE


Protection against amphetamine-induced neurotoxicity toward striatal dopamine neurons in rodents by LY274614, an excitatory amino acid antagonist.

LY274614, 3SR,4aRS,6SR,8aRS-6-[phosphonomethyl]decahydr oisoquinoline-3- carboxylic acid, has been described as a potent antagonist of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor. Here its ability to antagonize the prolonged depletion of dopamine in the striatum by amphetamine in iprindole-treated rats is reported. A single 18.4 mg/kg (i.p.) dose of (+/-)-amphetamine hemisulfate, given to rats pretreated with iprindole, resulted in persistent depletion of dopamine in the striatum 1 week later. This prolonged depletion of dopamine in the striatum was antagonized by dizocilpine (MK-801, a non-competitive antagonist of NMDA receptors) or by LY274614 (a competitive antagonist of NMDA receptors). The protective effect of LY274614 was dose-dependent, being maximum at 10-40 mgkg (i.p.). A 10 mg/kg dose of LY274614 was effective in antagonizing the depletion of dopamine in the striatum, when given as long as 8 hr prior to amphetamine but not when given 24 hr prior to amphetamine. Depletion of dopamine in the striatum was also antagonized when LY274614 was given after the injection of amphetamine; LY274614 protected when given up to 4 hr after but not when given 8 or 24 hr after amphetamine. The prolonged depletion of dopamine in the striatum in mice, given multiple injections of methamphetamine, was also antagonized dose-dependently and completely by LY274614. The data strengthen the evidence that the neurotoxic effect of amphetamine and related compounds toward nigrostriatal dopamine neurons involves NMDA receptors and that LY274614 is an NMDA receptor antagonist with long-lasting in vivo effects in rats.

amphetamine

neurotoxicity

dopamine

amino acid

N-methyl-D-aspartate

NMDA

glutamate

dopamine

amphetamine

iprindole

amphetamine

iprindole

dopamine

dopamine

dizocilpine

NMDA

NMDA

dopamine

amphetamine

amphetamine

dopamine

amphetamine

amphetamine

dopamine

methamphetamine

neurotoxic

amphetamine

dopamine

NMDA

NMDA


Neonatal pyridoxine responsive convulsions due to isoniazid therapy.

A 17-day-old infant on isoniazid therapy 13 mg/kg daily from birth because of maternal tuberculosis was admitted after 4 days of clonic fits. No underlying infective or biochemical cause could be found. The fits ceased within 4 hours of administering intramuscular pyridoxine, suggesting an aetiology of pyridoxine deficiency secondary to isoniazid medication.

pyridoxine

convulsions

isoniazid

isoniazid

tuberculosis

clonic fits

fits

pyridoxine

pyridoxine

isoniazid


Reversal by phenylephrine of the beneficial effects of intravenous nitroglycerin in patients with acute myocardial infarction.

Nitroglycerin has been shown to reduce ST-segment elevation during acute myocardial infarction, an effect potentiated in the dog by agents that reverse nitroglycerin-induced hypotension. Our study was designed to determine the effects of combined nitroglycerin and phenylephrine therapy. Ten patients with acute transmural myocardial infarctions received intravenous nitroglycerin, sufficient to reduce mean arterial pressure from 107 +/- 6 to 85 +/- 6 mm Hg (P less than 0.001), for 60 minutes. Left ventricular filling pressure decreased from 19 +/- 2 to 11 +/- 2 mm Hg (P less than 0.001). SigmaST, the sum of ST-segment elevations in 16 precordial leads, decreased (P less than 0.02) with intravenous nitroglycerin. Subsequent addition of phenylephrine infusion, sufficient to re-elevate mean arterial pressure to 106 +/- 4 mm Hg (P less than 0.001) for 30 minutes, increased left ventricular filling pressure to 17 +/- 2 mm Hg (P less than 0.05) and also significantly increased sigmaST (P less than 0.05). Our results suggest that addition of phenylephrine to nitroglycerin is not beneficial in the treatment of patients with acute myocardial infarction.

phenylephrine

nitroglycerin

acute myocardial infarction

Nitroglycerin

acute myocardial infarction

nitroglycerin

hypotension

nitroglycerin

phenylephrine

myocardial infarctions

nitroglycerin

nitroglycerin

phenylephrine

phenylephrine

nitroglycerin

acute myocardial infarction


Elevation of ADAM10, ADAM17, MMP-2 and MMP-9 expression with media degeneration features CaCl2-induced thoracic aortic aneurysm in a rat model.

PURPOSE: This study was designed to establish a rat model of thoracic aortic aneurysm (TAA) by calcium chloride (CaCl(2))-induced arterial injury and to explore the potential role of a disintegrin and metalloproteinase (ADAM), matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) in TAA formation. METHODS: Thoracic aorta of male Sprague-Dawley rats was exposed to 0.5M CaCl(2) or normal saline (NaCl). After 12weeks, animals were euthanized, and CaCl(2)-treated, CaCl(2)-untreated (n=12) and NaCl-treated aortic segments (n=12) were collected for histological and molecular assessments. MMP-TIMP and ADAM mRNAs were semi-quantitatively analyzed and protein expressions were determined by immunohistochemistry. RESULTS: Despite similar external diameters among CaCl(2)-treated, non-CaCl(2)-treated and NaCl-treated segments, aneurymal alteration (n=6, 50%), media degeneration with regional disruption, fragmentation of elastic fiber, and increased collagen deposition (n=12, 100%) were demonstrated in CaCl(2)-treated segments. MMP-2, MMP-9, ADAM-10 and ADAM-17 mRNA levels were increased in CaCl(2)-treated segments (all p<0.01), with trends of elevation in CaCl(2)-untreated segments, as compared with NaCl-treated segments. Immunohistochemistry displayed significantly increased expressions of MMP-2, MMP-9, ADAM-10 and ADAM-17 (all p<0.01) in intima and media for CaCl(2)-treated segments. TIMP mRNA and tissue levels did not differ obviously among the three aortic segments. CONCLUSION: This study establishes a TAA model by periarterial CaCl(2) exposure in rats, and demonstrates a significant elevation of expression of MMP-2, MMP-9, ADAM10 and ADAM17 in the pathogenesis of vascular remodeling.

thoracic aortic aneurysm

thoracic aortic aneurysm

TAA

calcium chloride

arterial injury

TAA

NaCl

NaCl

NaCl

NaCl

TAA


When drugs disappear from the patient: elimination of intravenous medication by hemodiafiltration.

Twenty-three hours after heart transplantation, life-threatening acute right heart failure was diagnosed in a patient requiring continuous venovenous hemodiafiltration (CVVHDF). Increasing doses of catecholamines, sedatives, and muscle relaxants administered through a central venous catheter were ineffective. However, a bolus of epinephrine injected through an alternative catheter provoked a hypertensive crisis. Thus, interference with the central venous infusion by the dialysis catheter was suspected. The catheters were changed, and hemodynamics stabilized at lower catecholamine doses. When the effects of IV drugs are inadequate in patients receiving CVVHDF, interference with adjacent catheters resulting in elimination of the drug by CVVHDF should be suspected.

right heart failure

catecholamines

epinephrine

hypertensive

catecholamine


Long-term glutamate supplementation failed to protect against peripheral neurotoxicity of paclitaxel.

Toxic peripheral neuropathy is still a significant limiting factor for chemotherapy with paclitaxel (PAC), although glutamate and its closely related amino acid glutamine were claimed to ameliorate PAC neurotoxicity. This pilot trial aimed to evaluate the role of glutamate supplementation for preventing PAC-induced peripheral neuropathy in a randomized, placebo-controlled, double-blinded clinical and electro-diagnostic study. Forty-three ovarian cancer patients were available for analysis following six cycles of the same PAC-containing regimen: 23 had been supplemented by glutamate all along the treatment period, at a daily dose of three times 500 mg (group G), and 20 had received a placebo (group P). Patients were evaluated by neurological examinations, questionnaires and sensory-motor nerve conduction studies. There was no significant difference in the frequency of signs or symptoms between the two groups although neurotoxicity symptoms presented mostly with lower scores of severity in group G. However, this difference reached statistical significance only with regard to reported pain sensation (P = 0.011). Also the frequency of abnormal electro-diagnostic findings showed similarity between the two groups (G: 7/23 = 30.4%; P: 6/20 = 30%). This pilot study leads to the conclusion that glutamate supplementation at the chosen regimen fails to protect against peripheral neurotoxicity of PAC.

glutamate

peripheral neurotoxicity

paclitaxel

peripheral neuropathy

paclitaxel

PAC

glutamate

amino acid

glutamine

PAC

neurotoxicity

glutamate

PAC

peripheral neuropathy

ovarian cancer

PAC

glutamate

neurotoxicity

pain

glutamate

peripheral neurotoxicity

PAC


Attentional modulation of perceived pain intensity in capsaicin-induced secondary hyperalgesia.

Perceived pain intensity is modulated by attention. However, it is not known that how pain intensity ratings are affected by attention in capsaicin-induced secondary hyperalgesia. Here we show that perceived pain intensity in secondary hyperalgesia is decreased when attention is distracted away from the painful pinprick stimulus with a visual task. Furthermore, it was found that the magnitude of attentional modulation in secondary hyperalgesia is very similar to that of capsaicin-untreated, control condition. Our findings, showing no interaction between capsaicin treatment and attentional modulation suggest that capsaicin-induced secondary hyperalgesia and attention might affect mechanical pain through independent mechanisms.

pain

capsaicin

hyperalgesia

pain

pain

capsaicin

hyperalgesia

pain

hyperalgesia

hyperalgesia

capsaicin

capsaicin

capsaicin

hyperalgesia

pain


Testosterone-dependent hypertension and upregulation of intrarenal angiotensinogen in Dahl salt-sensitive rats.

Blood pressure (BP) is more salt sensitive in men than in premenopausal women. In Dahl salt-sensitive rats (DS), high-salt (HS) diet increases BP more in males than females. In contrast to the systemic renin-angiotensin system, which is suppressed in response to HS in male DS, intrarenal angiotensinogen expression is increased, and intrarenal levels of ANG II are not suppressed. In this study, the hypothesis was tested that there is a sexual dimorphism in HS-induced upregulation of intrarenal angiotensinogen mediated by testosterone that also causes increases in BP and renal injury. On a low-salt (LS) diet, male DS had higher levels of intrarenal angiotensinogen mRNA than females. HS diet for 4 wk increased renal cortical angiotensinogen mRNA and protein only in male DS, which was prevented by castration. Ovariectomy of female DS had no effect on intrarenal angiotensinogen expression on either diet. Radiotelemetric BP was similar between males and castrated rats on LS diet. HS diet for 4 wk caused a progressive increase in BP, protein and albumin excretion, and glomerular sclerosis in male DS rats, which were attenuated by castration. Testosterone replacement in castrated DS rats increased BP, renal injury, and upregulation of renal angiotensinogen associated with HS diet. Testosterone contributes to the development of hypertension and renal injury in male DS rats on HS diet possibly through upregulation of the intrarenal renin-angiotensin system.

Testosterone

hypertension

salt

salt

salt

salt

angiotensin

testosterone

renal injury

salt

glomerular sclerosis

Testosterone

renal injury

Testosterone

hypertension

renal injury

angiotensin


Prenatal protein deprivation alters dopamine-mediated behaviors and dopaminergic and glutamatergic receptor binding.

Epidemiological evidence indicates that prenatal nutritional deprivation may increase the risk of schizophrenia. The goal of these studies was to use an animal model to examine the effects of prenatal protein deprivation on behaviors and receptor binding with relevance to schizophrenia. We report that prenatally protein deprived (PD) female rats showed an increased stereotypic response to apomorphine and an increased locomotor response to amphetamine in adulthood. These differences were not observed during puberty. No changes in haloperidol-induced catalepsy or MK-801-induced locomotion were seen following PD. In addition, PD female rats showed increased (3)H-MK-801 binding in the striatum and hippocampus, but not in the cortex. PD female rats also showed increased (3)H-haloperidol binding and decreased dopamine transporter binding in striatum. No statistically significant changes in behavior or receptor binding were found in PD males with the exception of increased (3)H-MK-801 binding in cortex. This animal model may be useful to explore the mechanisms by which prenatal nutritional deficiency enhances risk for schizophrenia in humans and may also have implications for developmental processes leading to differential sensitivity to drugs of abuse.

dopamine

schizophrenia

schizophrenia

apomorphine

amphetamine

haloperidol

catalepsy

H

H

haloperidol

dopamine

H

nutritional deficiency

schizophrenia


mToR inhibitors-induced proteinuria: mechanisms, significance, and management.

Massive urinary protein excretion has been observed after conversion from calcineurin inhibitors to mammalian target of rapamycin (mToR) inhibitors, especially sirolimus, in renal transplant recipients with chronic allograft nephropathy. Because proteinuria is a major predictive factor of poor transplantation outcome, many studies focused on this adverse event during the past years. Whether proteinuria was due to sirolimus or only a consequence of calcineurin inhibitors withdrawal remained unsolved until high range proteinuria has been observed during sirolimus therapy in islet transplantation and in patients who received sirolimus de novo. Podocyte injury and focal segmental glomerulosclerosis have been related to mToR inhibition in some patients, but the pathways underlying these lesions remain hypothetic. We discuss herein the possible mechanisms and the significance of mToR blockade-induced proteinuria.

proteinuria

rapamycin

sirolimus

chronic allograft nephropathy

proteinuria

proteinuria

sirolimus

proteinuria

sirolimus

sirolimus

glomerulosclerosis

proteinuria


Hypothalamic prolactin receptor messenger ribonucleic acid levels, prolactin signaling, and hyperprolactinemic inhibition of pulsatile luteinizing hormone secretion are dependent on estradiol.

Hyperprolactinemia can reduce fertility and libido. Although central prolactin actions are thought to contribute to this, the mechanisms are poorly understood. We first tested whether chronic hyperprolactinemia inhibited two neuroendocrine parameters necessary for female fertility: pulsatile LH secretion and the estrogen-induced LH surge. Chronic hyperprolactinemia induced by the dopamine antagonist sulpiride caused a 40% reduction LH pulse frequency in ovariectomized rats, but only in the presence of chronic low levels of estradiol. Sulpiride did not affect the magnitude of a steroid-induced LH surge or the percentage of GnRH neurons activated during the surge. Estradiol is known to influence expression of the long form of prolactin receptors (PRL-R) and components of prolactin's signaling pathway. To test the hypothesis that estrogen increases PRL-R expression and sensitivity to prolactin, we next demonstrated that estradiol greatly augments prolactin-induced STAT5 activation. Lastly, we measured PRL-R and suppressor of cytokine signaling (SOCS-1 and -3 and CIS, which reflect the level of prolactin signaling) mRNAs in response to sulpiride and estradiol. Sulpiride induced only SOCS-1 in the medial preoptic area, where GnRH neurons are regulated, but in the arcuate nucleus and choroid plexus, PRL-R, SOCS-3, and CIS mRNA levels were also induced. Estradiol enhanced these effects on SOCS-3 and CIS. Interestingly, estradiol also induced PRL-R, SOCS-3, and CIS mRNA levels independently. These data show that GnRH pulse frequency is inhibited by chronic hyperprolactinemia in a steroid-dependent manner. They also provide evidence for estradiol-dependent and brain region-specific regulation of PRL-R expression and signaling responses by prolactin.

ribonucleic acid

hyperprolactinemic

estradiol

Hyperprolactinemia

hyperprolactinemia

estrogen

hyperprolactinemia

dopamine

sulpiride

estradiol

Sulpiride

steroid

Estradiol

estrogen

estradiol

sulpiride

estradiol

Sulpiride

Estradiol

estradiol

hyperprolactinemia

steroid

estradiol


Estrogen prevents cholesteryl ester accumulation in macrophages induced by the HIV protease inhibitor ritonavir.

Individuals with HIV can now live long lives with drug therapy that often includes protease inhibitors such as ritonavir. Many patients, however, develop negative long-term side effects such as premature atherosclerosis. We have previously demonstrated that ritonavir treatment increases atherosclerotic lesion formation in male mice to a greater extent than in female mice. Furthermore, peripheral blood monocytes isolated from ritonavir-treated females had less cholesteryl ester accumulation. In the present study, we have investigated the molecular mechanisms by which female hormones influence cholesterol metabolism in macrophages in response to the HIV protease inhibitor ritonavir. We have utilized the human monocyte cell line, THP-1 as a model to address this question. Briefly, cells were differentiated for 72 h with 100 nM PMA to obtain a macrophage-like phenotype in the presence or absence of 1 nM 17beta-estradiol (E2), 100 nM progesterone or vehicle (0.01% ethanol). Cells were then treated with 30 ng/ml ritonavir or vehicle in the presence of aggregated LDL for 24 h. Cell extracts were harvested, and lipid or total RNA was isolated. E2 decreased the accumulation of cholesteryl esters in macrophages following ritonavir treatment. Ritonavir increased the expression of the scavenger receptor, CD36 mRNA, responsible for the uptake of LDL. Additionally, ritonavir treatment selectively increased the relative levels of PPARgamma mRNA, a transcription factor responsible for the regulation of CD36 mRNA expression. Treatment with E2, however, failed to prevent these increases at the mRNA level. E2 did, however, significantly suppress CD36 protein levels as measured by fluorescent immunocytochemistry. This data suggests that E2 modifies the expression of CD36 at the level of protein expression in monocyte-derived macrophages resulting in reduced cholesteryl ester accumulation following ritonavir treatment.

cholesteryl ester

ritonavir

ritonavir

premature atherosclerosis

ritonavir

atherosclerotic lesion

ritonavir

cholesteryl ester

cholesterol

ritonavir

progesterone

ethanol

ritonavir

cholesteryl esters

ritonavir

Ritonavir

ritonavir

cholesteryl ester

ritonavir


Upregulation of brain expression of P-glycoprotein in MRP2-deficient TR(-) rats resembles seizure-induced up-regulation of this drug efflux transporter in normal rats.

PURPOSE: The multidrug resistance protein 2 (MRP2) is a drug efflux transporter that is expressed predominantly at the apical domain of hepatocytes but seems also to be expressed at the apical membrane of brain capillary endothelial cells that form the blood-brain barrier (BBB). MRP2 is absent in the transport-deficient (TR(-)) Wistar rat mutant, so that this rat strain was very helpful in defining substrates of MRP2 by comparing tissue concentrations or functional activities of compounds in MRP2-deficient rats with those in transport-competent Wistar rats. By using this strategy to study the involvement of MRP2 in brain access of antiepileptic drugs (AEDs), we recently reported that phenytoin is a substrate for MRP2 in the BBB. However, one drawback of such studies in genetically deficient rats is the fact that compensatory changes with upregulation of other transporters can occur. This prompted us to study the brain expression of P-glycoprotein (Pgp), a major drug efflux transporter in many tissues, including the BBB, in TR(-) rats compared with nonmutant (wild-type) Wistar rats. METHODS: The expression of MRP2 and Pgp in brain and liver sections of TR(-) rats and normal Wistar rats was determined with immunohistochemistry, by using a novel, highly selective monoclonal MRP2 antibody and the monoclonal Pgp antibody C219, respectively. RESULTS: Immunofluorescence staining with the MRP2 antibody was found to label a high number of microvessels throughout the brain in normal Wistar rats, whereas such labeling was absent in TR(-) rats. TR(-) rats exhibited a significant up-regulation of Pgp in brain capillary endothelial cells compared with wild-type controls. No such obvious upregulation of Pgp was observed in liver sections. A comparable overexpression of Pgp in the BBB was obtained after pilocarpine-induced seizures in wild-type Wistar rats. Experiments with systemic administration of the Pgp substrate phenobarbital and the selective Pgp inhibitor tariquidar in TR(-) rats substantiated that Pgp is functional and compensates for the lack of MRP2 in the BBB. CONCLUSIONS: The data on TR(-) rats indicate that Pgp plays an important role in the compensation of MRP2 deficiency in the BBB. Because such a compensatory mechanism most likely occurs to reduce injury to the brain from cytotoxic compounds, the present data substantiate the concept that MRP2 performs a protective role in the BBB. Furthermore, our data suggest that TR(-) rats are an interesting tool to study consequences of overexpression of Pgp in the BBB on access of drugs in the brain, without the need of inducing seizures or other Pgp-enhancing events for this purpose.

seizure

phenytoin

pilocarpine

seizures

phenobarbital

tariquidar

injury to the brain

seizures


Use of chromosome substitution strains to identify seizure susceptibility loci in mice.

Seizure susceptibility varies among inbred mouse strains. Chromosome substitution strains (CSS), in which a single chromosome from one inbred strain (donor) has been transferred onto a second strain (host) by repeated backcrossing, may be used to identify quantitative trait loci (QTLs) that contribute to seizure susceptibility. QTLs for susceptibility to pilocarpine-induced seizures, a model of temporal lobe epilepsy, have not been reported, and CSS have not previously been used to localize seizure susceptibility genes. We report QTLs identified using a B6 (host) x A/J (donor) CSS panel to localize genes involved in susceptibility to pilocarpine-induced seizures. Three hundred fifty-five adult male CSS mice, 58 B6, and 39 A/J were tested for susceptibility to pilocarpine-induced seizures. Highest stage reached and latency to each stage were recorded for all mice. B6 mice were resistant to seizures and slower to reach stages compared to A/J mice. The CSS for Chromosomes 10 and 18 progressed to the most severe stages, diverging dramatically from the B6 phenotype. Latencies to stages were also significantly shorter for CSS10 and CSS18 mice. CSS mapping suggests seizure susceptibility loci on mouse Chromosomes 10 and 18. This approach provides a framework for identifying potentially novel homologous candidate genes for human temporal lobe epilepsy.

seizure

Seizure

seizure

pilocarpine

seizures

temporal lobe epilepsy

seizure

pilocarpine

seizures

pilocarpine

seizures

seizures

seizure

temporal lobe epilepsy


Investigation of mitochondrial involvement in the experimental model of epilepsy induced by pilocarpine.

Mitochondrial abnormalities have been associated with several aspects of epileptogenesis, such as energy generation, control of cell death, neurotransmitter synthesis, and free radical (FR) production. Increased production of FRs may cause mtDNA damage leading to decreased activities of oxidative phosphorylation complexes containing mtDNA-encoded subunits. In this study, we investigated whether increased generation of FR during status epilepticus would be sufficient to provoke abnormalities in mtDNA and in the expression and activity of cytochrome c oxidase (CCO), complex IV of the respiratory chain, in the chronic phase of the pilocarpine model of temporal lobe epilepsy. DNA analysis revealed low amounts of a 4.8 kb mtDNA deletion but with no differences in frequency or quantity in the control and experimental groups. We did not find abnormalities in the expression and distribution of an mtDNA-encoded subunit of CCO (CCO-I) or a relative decrease in CCO-I when compared with nuclear-encoded subunits (CCO-IV and SDH-fp). No abnormality in CCO activity was observed through histochemistry. Although evidences of mitochondrial abnormalities were found in previously published studies, our results do not suggest that the FRs, generated during the acute phase, determined important abnormalities in mtDNA, in expression of CCO-I, and in CCO activity.

epilepsy

pilocarpine

Mitochondrial abnormalities

death

status epilepticus

pilocarpine

temporal lobe epilepsy

mitochondrial abnormalities


Causes of acute thrombotic microangiopathy in patients receiving kidney transplantation.

OBJECTIVES: Thrombotic microangiopathy is a well-known problem in patients following renal transplantation. In postrenal transplantation, thrombotic microangiopathy is often a reflection of hemolytic uremic syndrome. We aimed to determine the causes of thrombotic microangiopathy in a population of renal transplantation recipients and discuss the literature. MATERIALS AND METHODS: We investigated the causes of thrombotic microangiopathy during a 1-year period, from June 2003 to June 2004, at the King Fahad National Guard Hospital in Riyadh, Saudi Arabia, by reviewing the slides of all transplant biopsies (n=25) performed during this interval. Pre- and posttransplant crossmatching was done when possible. RESULTS: Five cases of thrombotic microangiopathy were found. Three of these cases were from the 25 transplantations performed at King Fahad National Guard Hospital, while the other 2 transplantations had been performed abroad and were referred to us for follow-up. Three cases were related to cyclosporine, and 1 case was secondary to both cyclosporine and tacrolimus. The fifth case had features of thrombotic microangiopathy related to an antiphospholipid syndrome in a patient with systemic lupus erythematosus. CONCLUSIONS: In the literature, the most-frequent cause of hemolytic uremic syndrome in patients following renal transplantation is recurrence of the hemolytic uremic syndrome. Other causes include drug-related (cyclosporine, tacrolimus) toxicity, procoagulant status, and antibody-mediated rejection. We found that the most-frequent cause of thrombotic microangiopathy was drug related, secondary mainly to cyclosporine. In the current study, the frequency of thrombotic microangiopathy was similar to the percentage reported in the literature (20%).

thrombotic microangiopathy

Thrombotic microangiopathy

thrombotic microangiopathy

hemolytic uremic syndrome

thrombotic microangiopathy

thrombotic microangiopathy

thrombotic microangiopathy

cyclosporine

cyclosporine

tacrolimus

thrombotic microangiopathy

antiphospholipid syndrome

systemic lupus erythematosus

hemolytic uremic syndrome

hemolytic uremic syndrome

cyclosporine

tacrolimus

toxicity

thrombotic microangiopathy

cyclosporine

thrombotic microangiopathy


Severe reversible left ventricular systolic and diastolic dysfunction due to accidental iatrogenic epinephrine overdose.

Catecholamine-induced cardiomyopathy due to chronic excess of endogenous catecholamines has been recognized for decades as a clinical phenomenon. In contrast, reports of myocardial dysfunction due to acute iatrogenic overdose are rare. A 35-year-old woman whose cervix uteri was inadvertently injected with 8 mg of epinephrine developed myocardial stunning that was characterized by severe hemodynamic compromise, profound, albeit transient, left ventricular systolic and diastolic dysfunction, and only modestly elevated biochemical markers of myocardial necrosis. Our case illustrates the serious consequences of medical errors that can be avoided through improved medication labeling and staff supervision.

epinephrine

overdose

Catecholamine

cardiomyopathy

catecholamines

myocardial dysfunction

overdose

epinephrine

myocardial stunning

myocardial necrosis


Urinary bladder cancer in Wegener's granulomatosis: risks and relation to cyclophosphamide.

OBJECTIVE: To assess and characterise the risk of bladder cancer, and its relation to cyclophosphamide, in patients with Wegener's granulomatosis. METHODS: In the population based, nationwide Swedish Inpatient Register a cohort of 1065 patients with Wegener's granulomatosis, 1969-95, was identified. Through linkage with the Swedish Cancer Register, all subjects in this cohort diagnosed with bladder cancer were identified. Nested within the cohort, a matched case-control study was performed to estimate the association between cyclophosphamide and bladder cancer using odds ratios (ORs) as relative risk. In the cohort the cumulative risk of bladder cancer after Wegener's granulomatosis, and the relative prevalence of a history of bladder cancer at the time of diagnosis of Wegener's granulomatosis, were also estimated. RESULTS: The median cumulative doses of cyclophosphamide among cases (n = 11) and controls (n = 25) were 113 g and 25 g, respectively. The risk of bladder cancer doubled for every 10 g increment in cyclophosphamide (OR = 2.0, 95% confidence interval (CI) 0.8 to 4.9). Treatment duration longer than 1 year was associated with an eightfold increased risk (OR = 7.7, 95% CI 0.9 to 69). The absolute risk for bladder cancer in the cohort reached 10% 16 years after diagnosis of Wegener's granulomatosis, and a history of bladder cancer was (non-significantly) twice as common as expected at the time of diagnosis of Wegener's granulomatosis. CONCLUSION: The results indicate a dose-response relationship between cyclophosphamide and the risk of bladder cancer, high cumulative risks in the entire cohort, and also the possibility of risk factors operating even before Wegener's granulomatosis.

Urinary bladder cancer

Wegener's granulomatosis

cyclophosphamide

bladder cancer

cyclophosphamide

Wegener's granulomatosis

Wegener's granulomatosis

Cancer

bladder cancer

cyclophosphamide

bladder cancer

bladder cancer

Wegener's granulomatosis

bladder cancer

Wegener's granulomatosis

cyclophosphamide

bladder cancer

cyclophosphamide

bladder cancer

Wegener's granulomatosis

bladder cancer

Wegener's granulomatosis

cyclophosphamide

bladder cancer

Wegener's granulomatosis


L-arginine transport in humans with cortisol-induced hypertension.

A deficient L-arginine-nitric oxide system is implicated in cortisol-induced hypertension. We investigate whether abnormalities in L-arginine uptake contribute to this deficiency. Eight healthy men were recruited. Hydrocortisone acetate (50 mg) was given orally every 6 hours for 24 hours after a 5-day fixed-salt diet (150 mmol/d). Crossover studies were performed 2 weeks apart. Thirty milliliters of blood was obtained for isolation of peripheral blood mononuclear cells after each treatment period. L-arginine uptake was assessed in mononuclear cells incubated with L-arginine (1 to 300 micromol/L), incorporating 100 nmol/L [3H]-l-arginine for a period of 5 minutes at 37 degrees C. Forearm [3H]-L-arginine extraction was calculated after infusion of [3H]-L-arginine into the brachial artery at a rate of 100 nCi/min for 80 minutes. Deep forearm venous samples were collected for determination of L-arginine extraction. Plasma cortisol concentrations were significantly raised during the active phase (323+/-43 to 1082+/-245 mmol/L, P<0.05). Systolic blood pressure was elevated by an average of 7 mm Hg. Neither L-arginine transport into mononuclear cells (placebo vs active, 26.3+/-3.6 vs 29.0+/-2.1 pmol/10 000 cells per 5 minutes, respectively, at an l-arginine concentration of 300 micromol/L) nor L-arginine extraction in the forearm (at 80 minutes, placebo vs active, 1 868 904+/-434 962 vs 2 013 910+/-770 619 disintegrations per minute) was affected by cortisol treatment; ie, that L-arginine uptake is not affected by short-term cortisol treatment. We conclude that cortisol-induced increases in blood pressure are not associated with abnormalities in the l-arginine transport system.

L-arginine

cortisol

hypertension

L-arginine

nitric oxide

cortisol

hypertension

L-arginine

Hydrocortisone acetate

L-arginine

L-arginine

L-arginine

cortisol

L-arginine

l-arginine

L-arginine

cortisol

L-arginine

cortisol

cortisol

increases in blood pressure

l-arginine


MR imaging with quantitative diffusion mapping of tacrolimus-induced neurotoxicity in organ transplant patients.

Our objective was to investigate brain MR imaging findings and the utility of diffusion-weighted (DW) imaging in organ transplant patients who developed neurologic symptoms during tacrolimus therapy. Brain MR studies, including DW imaging, were prospectively performed in 14 organ transplant patients receiving tacrolimus who developed neurologic complications. In each patient who had abnormalities on the initial MR study, a follow-up MR study was performed 1 month later. Apparent diffusion coefficient (ADC) values on the initial MR study were correlated with reversibility of the lesions. Of the 14 patients, 5 (35.7%) had white matter abnormalities, 1 (7.1%) had putaminal hemorrhage, and 8 (57.1%) had normal findings on initial MR images. Among the 5 patients with white matter abnormalities, 4 patients (80.0%) showed higher than normal ADC values on initial MR images, and all showed complete resolution on follow-up images. The remaining 1 patient (20.0%) showed lower than normal ADC value and showed incomplete resolution with cortical laminar necrosis. Diffusion-weighted imaging may be useful in predicting the outcomes of the lesions of tacrolimus-induced neurotoxicity.

tacrolimus

neurotoxicity

tacrolimus

tacrolimus

neurologic complications

white matter abnormalities

putaminal hemorrhage

white matter abnormalities

cortical laminar necrosis

tacrolimus

neurotoxicity


Octreotide-induced hypoxemia and pulmonary hypertension in premature neonates.

The authors report 2 cases of premature neonates who had enterocutaneous fistula complicating necrotizing enterocolitis. Pulmonary hypertension developed after administration of a somatostatin analogue, octreotide, to enhance resolution of the fistula. The authors discuss the mechanism of the occurrence of this complication and recommend caution of its use in high-risk premature neonates.

Octreotide

hypoxemia

pulmonary hypertension

fistula

necrotizing enterocolitis

Pulmonary hypertension

octreotide

fistula


Sequential observations of exencephaly and subsequent morphological changes by mouse exo utero development system: analysis of the mechanism of transformation from exencephaly to anencephaly.

Anencephaly has been suggested to develop from exencephaly; however, there is little direct experimental evidence to support this, and the mechanism of transformation remains unclear. We examined this theory using the exo utero development system that allows direct and sequential observations of mid- to late-gestation mouse embryos. We observed the exencephaly induced by 5-azacytidine at embryonic day 13.5 (E13.5), let the embryos develop exo utero until E18.5, and re-observed the same embryos at E18.5. We confirmed several cases of transformation from exencephaly to anencephaly. However, in many cases, the exencephalic brain tissue was preserved with more or less reduction during this period. To analyze the transformation patterns, we classified the exencephaly by size and shape of the exencephalic tissue into several types at E13.5 and E18.5. It was found that the transformation of exencephalic tissue was not simply size-dependent, and all cases of anencephaly at E18.5 resulted from embryos with a large amount of exencephalic tissue at E13.5. Microscopic observation showed the configuration of exencephaly at E13.5, frequent hemorrhaging and detachment of the neural plate from surface ectoderm in the exencephalic head at E15.5, and multiple modes of reduction in the exencephalic tissue at E18.5. From observations of the vasculature, altered distribution patterns of vessels were identified in the exencephalic head. These findings suggest that overgrowth of the exencephalic neural tissue causes the altered distribution patterns of vessels, subsequent peripheral circulatory failure and/or hemorrhaging in various parts of the exencephalic head, leading to the multiple modes of tissue reduction during transformation from exencephaly to anencephaly.

exencephaly

exencephaly

anencephaly

Anencephaly

exencephaly

exencephaly

exencephaly

anencephaly

exencephalic

exencephaly

exencephalic

exencephalic

anencephaly

exencephalic

exencephaly

hemorrhaging

exencephalic

exencephalic

exencephalic

exencephalic

circulatory failure

hemorrhaging

exencephalic

exencephaly

anencephaly


Acute cocaine-induced seizures: differential sensitivity of six inbred mouse strains.

Mature male and female mice from six inbred stains were tested for susceptibility to behavioral seizures induced by a single injection of cocaine. Cocaine was injected ip over a range of doses (50-100 mg/kg) and behavior was monitored for 20 minutes. Seizure end points included latency to forelimb or hindlimb clonus, latency to clonic running seizure and latency to jumping bouncing seizure. A range of strain specific sensitivities was documented with A/J and SJL mice being most sensitive and C57BL/6J most resistant. DBA/2J, BALB/cByJ and NZW/LacJ strains exhibited intermediate sensitivity. EEG recordings were made in SJL, A/J and C57BL/6J mice revealing a close correspondence between electrical activity and behavior. Additionally, levels of cocaine determined in hippocampus and cortex were not different between sensitive and resistant strains. Additional studies of these murine strains may be useful for investigating genetic influences on cocaine-induced seizures.

cocaine

seizures

seizures

cocaine

Cocaine

Seizure

seizure

seizure

cocaine

cocaine

seizures


Microangiopathic hemolytic anemia complicating FK506 (tacrolimus) therapy.

We describe 3 episodes of microangiopathic hemolytic anemia (MAHA) in 2 solid organ recipients under FK506 (tacrolimus) therapy. In both cases, discontinuation of FK506 and treatment with plasma exchange, fresh frozen plasma replacement, corticosteroids, aspirin, and dipyridamole led to resolution of MAHA. In one patient, reintroduction of FK506 led to rapid recurrence of MAHA. FK506-associated MAHA is probably rare but physicians must be aware of this severe complication. In our experience and according to the literature, FK506 does not seem to cross-react with cyclosporin A (CyA), an immuno-suppressive drug already known to induce MAHA.

Microangiopathic hemolytic anemia

tacrolimus

microangiopathic hemolytic anemia

MAHA

tacrolimus

corticosteroids

aspirin

dipyridamole

MAHA

MAHA

MAHA

cyclosporin A

CyA

MAHA


Variant ventricular tachycardia in desipramine toxicity.

We report a case of variant ventricular tachycardia induced by desipramine toxicity. Unusual features of the arrhythmia are repetitive group beating, progressive shortening of the R-R interval, progressive widening of the QRS complex with eventual failure of intraventricular conduction, and changes in direction of the QRS axis. Recognition of variant ventricular tachycardia is important because therapy differs from that of classic ventricular tachycardia.

ventricular tachycardia

desipramine

toxicity

ventricular tachycardia

desipramine

toxicity

arrhythmia

ventricular tachycardia

ventricular tachycardia


Desipramine-induced delirium at "subtherapeutic" concentrations: a case report.

An elderly patient treated with low dose Desipramine developed a delirium while her plasma level was in the "subtherapeutic" range. Delirium, which may be induced by tricyclic drug therapy in the elderly, can be caused by tricyclics with low anticholinergic potency. Therapeutic ranges for antidepressants that have been derived from general adult population studies may not be appropriate for the elderly. Further studies of specifically elderly patients are now required to establish safer and more appropriate guidelines for drug therapy.

Desipramine

delirium

Desipramine

delirium

Delirium

antidepressants


Mouse strain-dependent effect of amantadine on motility and brain biogenic amines.

The effect of amantadine hydrochloride, injected i.p. in 6 increments of 100 mg/kg each over 30 hr, on mouse motility and whole brain content of selected biogenic amines and major metabolites was studied in 4 strains of mice. These were the albino Sprague-Dawley ICR and BALB/C, the black C57BL/6 and the brown CDF-I mouse strains. Amantadine treatment produced a biphasic effect on mouse motility. The initial dose of amantadine depressed locomotor activity in all mouse strains studied with the BALB/C mice being the most sensitive. Subsequent amantadine treatments produced enhancement of motility from corresponding control in all mouse strains with the BALB/C mice being the least sensitive. The locomotor activity was decreased from corresponding controls in all strains studied, except for the ICR mice, during an overnight drug-free period following the fourth amantadine treatment. Readministration of amantadine, after a drug-free overnight period, increased motility from respective saline control in all strains with exception of the BALB/C mice where suppression of motility occurred. Treatment with amantadine did not alter whole brain dopamine levels but decreased the amounts of 3,4-dihydroxyphenylacetic acid in the BALB/C mice compared to saline control. Conversely, brain normetanephrine concentration was increased from saline control by amantadine in the BALB/C mice. The results suggest a strain-dependent effect of amantadine on motility and indicate a differential response to the acute and multiple dose regimens used. The BALB/C mouse was the most sensitive strain and could serve as the strain of choice for evaluating the side effects of amantadine. The biochemical results of brain biogenic amines of BALB/C mouse strain suggest a probable decrease of catecholamine turnover rate and/or metabolism by monoamine oxidase and a resulting increase in O-methylation of norepinephrine which may account for a behavioral depression caused by amantadine in the BALB/C mice.

amantadine

amines

amantadine hydrochloride

amines

Amantadine

amantadine

depressed

amantadine

amantadine

amantadine

suppression of motility

amantadine

dopamine

3,4-dihydroxyphenylacetic acid

normetanephrine

amantadine

amantadine

amantadine

amines

catecholamine

norepinephrine

behavioral depression

amantadine


No enhancement by phenobarbital of the hepatocarcinogenicity of a choline-devoid diet in the rat.

An experiment was performed to test whether inclusion of phenobarbital in a choline-devoid diet would increase the hepatocarcinogenicity of the diet. Groups of 5-week old male Fischer-344 rats were fed for 7-25 months semipurified choline-devoid or choline-supplemented diets, containing or not 0.06% phenobarbital. No hepatic preneoplastic nodules or hepatocellular carcinomas developed in rats fed the plain choline-supplemented diet, while one preneoplastic nodule and one hepatocellular carcinoma developed in two rats fed the same diet containing phenobarbital. The incidence of preneoplastic nodules and of hepatocellular carcinomas was 10% and 37%, respectively, in rats fed the plain choline-devoid diet, and 17% and 30%, in rats fed the phenobarbital-containing choline-devoid diet. The results evinced no enhancement of the hepatocarcinogenicity of the choline-devoid diet by phenobarbital. Sporadic neoplastic lesions were observed in organs other than the liver of some of the animals, irrespective of the diet fed.

phenobarbital

choline

phenobarbital

choline

choline

choline

phenobarbital

hepatocellular carcinomas

choline

hepatocellular carcinoma

phenobarbital

hepatocellular carcinomas

choline

phenobarbital

choline

choline

phenobarbital


Effect of direct intracoronary administration of methylergonovine in patients with and without variant angina.

The effects of intracoronary administration of methylergonovine were studied in 21 patients with variant angina and 22 patients with atypical chest pain and in others without angina pectoris (control group). Methylergonovine was administered continuously at a rate of 10 micrograms/min up to 50 micrograms. In all patients with variant angina, coronary spasm was provoked at a mean dose of 28 +/- 13 micrograms (mean +/- SD). In the control group neither ischemic ST change nor localized spasm occurred. The basal tone of the right coronary artery was significantly lower than that of the left coronary artery. The percentage of vasoconstriction of the right coronary artery was significantly higher than that of the left coronary artery. These results suggest that spasm provocation tests, which use an intracoronary injection of a relatively low dose of methylergonovine, have a high sensitivity in variant angina and the vasoreactivity of the right coronary artery may be greater than that of the other coronary arteries.

methylergonovine

variant angina

methylergonovine

variant angina

chest pain

angina pectoris

Methylergonovine

variant angina

coronary spasm

spasm

spasm

methylergonovine

variant angina


Dobutamine stress echocardiography: a sensitive indicator of diminished myocardial function in asymptomatic doxorubicin-treated long-term survivors of childhood cancer.

Doxorubicin is an effective anticancer chemotherapeutic agent known to cause acute and chronic cardiomyopathy. To develop a more sensitive echocardiographic screening test for cardiac damage due to doxorubicin, a cohort study was performed using dobutamine infusion to differentiate asymptomatic long-term survivors of childhood cancer treated with doxorubicin from healthy control subjects. Echocardiographic data from the experimental group of 21 patients (mean age 16 +/- 5 years) treated from 1.6 to 14.3 years (median 5.3) before this study with 27 to 532 mg/m2 of doxorubicin (mean 196) were compared with echocardiographic data from 12 normal age-matched control subjects. Graded dobutamine infusions of 0.5, 2.5, 5 and 10 micrograms/kg per min were administered. Echocardiographic Doppler studies were performed before infusion and after 15 min of infusion at each rate. Dobutamine infusion at 10 micrograms/kg per min was discontinued after six studies secondary to a 50% incidence rate of adverse symptoms. The most important findings were that compared with values in control subjects, end-systolic left ventricular posterior wall dimension and percent of left ventricular posterior wall thickening in doxorubicin-treated patients were decreased at baseline study and these findings were more clearly delineated with dobutamine stimulation. End-systolic left ventricular posterior wall dimension at baseline for the doxorubicin-treated group was 11 +/- 1.9 mm versus 13.1 +/- 1.5 mm for control subjects (p less than 0.01). End-systolic left ventricular posterior wall dimension at the 5-micrograms/kg per min dobutamine infusion for the doxorubicin-treated group was 14.1 +/- 2.4 mm versus 19.3 +/- 2.6 mm for control subjects (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Dobutamine

doxorubicin

cancer

Doxorubicin

cardiomyopathy

cardiac damage

doxorubicin

dobutamine

cancer

doxorubicin

doxorubicin

dobutamine

Dobutamine

doxorubicin

dobutamine

doxorubicin

dobutamine

doxorubicin