shukoor65/lab-rag-model huggingface dataset:
Slow toxins, biologic markers, and long-latency neurodegenerative disease in the western Pacific region. The western Pacific parkinsonism-dementia and amyotrophic lateral sclerosis complex is a prototypical neurodegenerative disorder found among inhabitants of Guam, New Guinea (Irian Jaya, Indonesia) and Japan (Kii Peninsula, Honshu). Nonviral environmental factors peculiar to the affected populations seem to play a prominent etiologic role. Although cause-effect relationships cannot be established by epidemiologic studies alone, we have shown in all three affected population groups that individuals develop the amyotrophic lateral sclerosis variant of this disorder after heavy exposure to the raw or incompletely detoxified seed of neurotoxic cycad plants. Since long periods may elapse between cycad exposure and the appearance of neurological disease in humans, cycads may harbor a "slow toxin" that causes the postmitotic neuron to undergo slow irreversible degeneration. Two cycad neurotoxins are recognized, one of which (cycasin) is known to have long-latency effects (tumorigenesis) on mitotic neurons and replicating cells in other tissues. This paper explores the possible relationship between tumorigenesis and long-latency neurotoxicity, and discusses possible biologic markers of cycad exposure and subclinical neurodegenerative disease.
Complications following thyroid surgery. The incidence of severe complications following thyroid gland surgery is a major reason to recommend total thyroidectomy or a less radical procedure in treating thyroid gland diseases. A retrospective study on 335 thyroidectomies was performed to assess the incidence of postoperative complications. Rates for hypocalcemia were based on patients undergoing bilateral procedures (n = 185) and on nerves at risk for recurrent laryngeal nerve injury (n = 513). Permanent hypocalcemia (8%) and unilateral laryngeal nerve injury (2.3%) were the major complications, with 0.8% having fatal complications. The achievement of long-term normal serum calcium levels has been the most frequent complication. Recurrent laryngeal nerve injury had a significant relationship with secondary procedures, histologic findings, and no nerve identification during surgery. In our series, major complications can be blamed on technical pitfalls, even in the hands of experienced surgeons.
Respiratory and circulatory analysis of CO2 output during exercise in chronic heart failure. BACKGROUND. The output of carbon dioxide (VCO2) is controlled by both hemodynamics and ventilation. To understand VCO2 in patients who have chronic heart failure (CHF), we studied 14 patients who had New York Heart Association functional class III failure by measurements of hemodynamics, ventilation, and arterial and venous blood gases at rest and at 50 W of cycle ergometry exercise. METHODS AND RESULTS. Fick principle analysis of VCO2 showed that because of a limited increase in cardiac output, CHF patients widened their venoarterial CO2 content difference from 4.9 +/- 3.5 ml/dl at rest to 11.1 +/- 4.0 ml/dl with exercise (p less than 0.05). This increase in CO2 content difference was achieved with no change in venous CO2 content (from 54.3 +/- 3.3 ml/dl at rest to 54.5 +/- 4.8 ml/dl at exercise, p = NS); however, there was a decrease of arterial CO2 content (from 49.4 +/- 3.7 ml/dl at rest to 43.4 +/- 2.3 ml/dl with exercise, p less than 0.05). Modeling of the CO2 tension-content relation showed that there would have been a small, nonproportional increase of venous CO2 content as venous CO2 tension increased from 43.2 +/- 1.8 mm Hg at rest to 55.3 +/- 4.2 mm Hg during exercise (p less than 0.05); however, the development of metabolic acidosis during exercise entirely blunted the increase of CO2 content. In contrast, both the shape of the tension-content relation and the acidosis of exercise further influenced the decrease of arterial CO2 content as arterial CO2 tension decreased from 37.0 +/- 2.9 mm Hg at rest to 32.0 +/- 3.4 mm Hg during exercise (p less than 0.05) as a result of excess ventilation. CONCLUSIONS. In CHF patients during exercise, the circulatory limitations imposed by a low cardiac output on VCO2 are compensated by a widened venoarterial CO2 content difference. The content difference is not widened through an increase of venous CO2 content but rather by a decrease of arterial CO2 content caused by arterial hypocapnia and metabolic acidosis.
A review of 35 endometrial ablations using the Nd:YAG laser for recurrent menometrorrhagia. Endometrial ablation with the Nd:YAG laser can be used to treat recurrent dysfunctional uterine bleeding. Two series of patients were studied. All suffered for at least 1 year with recurrent menometrorrhagia that was unresponsive to other treatments such as hormonal therapy or removal of polyps or fibroids. In the first series, 75 patients presenting with menometrorrhagia were considered for endometrial ablation using Nd:YAG laser, and 23 met conservative requirements. In the second series, 12 of the 25 patients considered met the conservative requirements. The patients in series I received danazol for 30 days before and 30 days after the procedure; patients in series II received leuprolide acetate. All patients were followed for at least 1 year after treatment was discontinued. Of the 35 patients in both series, 21 (60%) were found to have complete cessation of menstruation. Eleven (31.43%) resumed menstruating but at acceptable levels. Three patients (8.57%) had unsatisfactory results, one who later had a repeat ablation and two who had hysterectomies. Thus, 32 of 35 patients were successfully treated without further intervention after laser ablation. Nd:YAG endometrial ablation is efficacious and cost-effective for recurrent menometrorrhagia in selected patients. The additional benefit of this procedure is the avoidance of hysterectomies and postsurgical complications as well as the psychological consequences of a hysterectomy.
The stimulus responsible for the peritoneal fluid inflammation observed in infertile women with endometriosis. OBJECTIVE: We tested the hypothesis that menstrual debris from ectopic endometrium is the stimulus responsible for eliciting the peritoneal fluid (PF) inflammation observed in infertile women with endometriosis. DESIGN, SETTING, PATIENTS: The extent of endometriosis was correlated with the PF volume and total PF cell count retrospectively in 135 infertile women with endometriosis. RESULTS: The volume and total cell count were positively correlated, whereas the total cell count was negatively correlated with the extent of endometriosis. Despite a similar negative trend, no statistically significant correlation was noted between the volume and the extent of endometriosis. These relationships did not change when the data were reanalyzed deleting those pathological features contributing to the endometriosis score but not capable of producing intraperitoneal menstrual debris, i.e., adhesions and encapsulated ovarian endometriomas. CONCLUSIONS: These findings indicate that menstrual debris from ectopic endometrium is probably not a major factor in the elicitation of the observed PF inflammation in infertile women with endometriosis and suggest an inverse relationship may exist between PF inflammation and the extent of endometriosis.
Response to the cold pressor test in normotensive and hypertensive patients. The response to the cold pressor test (CPT) was studied in 49 normotensive (NT) and 73 patients with essential sustained hypertension (HT). Patients were classified as responders when they increased their systolic pressure (SBP) by at least 16 mm Hg or their diastolic blood pressure (DBP) by at least 12 mm Hg. Forty-seven out of seventy-three (64%) increased their mean blood pressure (MBP) by 18.6 +/- 1.4 mm Hg (mean +/- SEM) in response to CPT. In NT subjects 23 out of 49 (47%) were responders (MBP = 16.3 +/- 1.3 mm Hg). In NT, but not in HT, patients, a negative relationship was observed between MBP changes during CPT and age (P less than .001) or basal DBP (P less than .01). There was no relationship between blood pressure response and the presence of a family history of hypertension. A positive correlation was found in HT patients between basal levels of active renin (AR) in the upright position and MBP changes during CPT (P less than .001). Mean plasma AR was 24.2 +/- 3.5 pg/mL in nonresponders v 37.5 +/- 2.9 pg/mL in responders (P less than .001). In HT, but not in NT, patients, blood pressure changes were associated with a simultaneous increase in HR (P less than .01 between delta MBP and delta HR). These results suggest that blood pressure elevation during CPT is a very common reaction in young normotensive subjects especially in those that have the lowest mean blood pressure. Therefore it is unlikely that CPT may be used as a predictor test of future hypertension in this population.
Biochemical and morphological analysis of the interaction of epidermal growth factor and parathyroid hormone with UMR 106 osteosarcoma cells. The interaction of epidermal growth factor (EGF) and PTH with UMR 106 osteosarcoma cells was examined biochemically and morphologically. EGF inhibited PTH-stimulated adenylate cyclase activity in association with a reduction in PTH receptors and a decrease in the activity of the stimulatory guanyl nucleotide-binding protein (Gs). Universal inhibition of agonist-stimulated adenylate cyclase activity did not occur, inasmuch as EGF did not reduce prostaglandin E2-enhanced enzyme activity. The influence of EGF on PTH action correlated with its effect in the UMR 106 cell population of promoting entry into the cell cycle. Morphological analysis with radioautography indicated that both EGF and PTH receptors could be colocalized to certain UMR 106 cells, but that each were more abundantly distributed over discrete UMR 106 cell types. Based on the distribution of [3H]thymidine incorporation, EGF receptors were predominantly found over rapidly proliferating cells, whereas PTH receptors were most densely distributed over more quiescent cells. The results indicate that EGF and PTH receptors are localized over specific types within the heterogeneous population of UMR 106 cells and suggest that EGF may reduce PTH action in these cultures by enhancing the proliferation of progenitor cells lacking PTH receptors and reducing differentiation in this cell population, which leads to PTH receptor-enriched target cells. EGF and PTH receptors may, therefore, be useful as probes to examine both functional interactions and differentiation pathways among cells in osteoblast models in vitro and perhaps in vivo.
Computed tomography of the brain in kwashiorkor: a follow up study. Computed tomography of the brain was performed initially and after nutritional rehabilitation on 12 children with kwashiorkor. The severe cerebral shrinkage evident initially resolved after nutritional rehabilitation. The mechanism and significance of this reversible abnormality remains to be determined.
Intraarterial drug abuse: new treatment options. Accidental, intraarterial injections of abused substances continue to be difficult management problems because of severe vascular complications. Vasospasm probably plays an important role in the pathophysiology of this injury, in addition to the more accepted roles of thrombosis and endarteritis. Three patients with severe, upper extremity ischemia after intraarterial injection of heroin, methamphetamine, and meperidine were treated with intraarterial tolazoline and streptokinase, along with intravenous heparin. All three patients had improved perfusion, assessed both clinically and by angiography. The responses to treatment in these patients demonstrated the roles of vasospasm and thrombosis in the origin of this injury and the therapeutic benefits of appropriately administered vasodilators and thrombolytic agents.
Endogenous interferon-gamma, macrophage activation, and murine host defense against acute infection with Trypanosoma cruzi. Parenteral interferon-gamma (IFN-gamma) activates murine macrophages to inhibit Trypanosoma cruzi multiplication and diminishes parasitemia and mortality in acute infection. To investigate the role of endogenous IFN-gamma in acute infection, monoclonal antibody to IFN-gamma was injected intraperitoneally into mice. The 6250 neutralizing units given 24 and 96 h after infection reproducibly increased mortality (P less than .05). Histology sections showed markedly more nests of T. cruzi in treated mice. BALB/c, Swiss Webster, C57Bl/6, and C3H/HEN mice were susceptible to the effects of anti-IFN-gamma. Peritoneal macrophages from mice 4 days after infection and a single dose of 6250 units of anti-IFN-gamma had significantly reduced ability to inhibit T. cruzi multiplication. Multiple doses of anti-IFN-gamma delayed but did not prevent macrophage activation. These results indicate the critical role of endogenous IFN-gamma for macrophage activation and host defense against acute T. cruzi infection in mice.
Penetrating craniocerebral missile injuries in civilians: a retrospective analysis of 314 cases. Analysis of 314 cases of penetrating craniocerebral missile injuries in civilians revealed a high rate of early mortality, with 228 victims having died at the scene and a further 38 dead within 3 hours. Surgery was performed in 44 patients who had a preoperative Glasgow Coma Score of at least 4. Out of the 26 survivors, all operated upon, 19 had an adequate recovery (score of 0-3 on the expanded Glasgow Outcome Scale). Vigorous resuscitation and early surgery often resulted in useful survivals and occasionally in spectacular recoveries. However, the high mortality rate on the scene or soon after the injury restricted the possibility of effective management to a minority of cases.
Increased paracellular permeability in intrahepatic cholestasis induced by carmustine (BCNU) in rats. Carmustine [i.e., 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU)] is a drug with cholestatic potency both in experimental animals and in humans. To study the mechanisms involved in the development of the hepatic lesions, early changes in liver function in rats pretreated with the drug were investigated. Dosages and sampling times that did not result in hepatocellular injury, as indicated by release of marker enzymes, were applied. In isolated perfused livers from pretreated rats, bile flow and maximal secretion rate of taurocholate were decreased. An increase in biliary [14C]sucrose clearance suggested enhanced permeability of the bile tract and was correlated with increased inorganic phosphate concentration in bile. To assess the contribution of paracellular and transcellular pathways of sucrose, [14C]sucrose access into bile was analyzed by biliary off-kinetics after omission of the radioactive marker from the perfusion medium. An improved method was developed to quantitate the permeability of the bile tract by applying the classical flow equation to the paracellular portion of biliary sucrose clearance. With this method it was shown that pretreatment of rats with BCNU resulted in an increase in both diffusion and convection of paracellular sucrose from perfusate into bile. Accordingly, the fast access of horseradish peroxidase from perfusate into bile was facilitated in isolated perfused livers of BCNU-treated rats. The results indicate that an increase in paracellular permeability is an early alteration that may contribute to the development of hepatotoxic lesions caused by BCNU. It is shown that inert solute clearance can be used to assess paracellular permeability if the paracellular fraction is determined.
Radiographic evaluation and diagnosis of the failed frontal osteoplastic flap with fat obliteration. In the absence of evidence of suppurative disease, clinical assessment of the symptomatic patient after frontal osteoplastic flap with fat obliteration is difficult because the cause of the pain is often neuralgic or from chronic vascular headache. Among 59 patients who have undergone this procedure at our institution since 1979, four required revision surgery. These patients were evaluated by computed tomographic and magnetic resonance scans, and the radiographic findings were compared with those present in 20 asymptomatic subjects. On the basis of the results of this study, we believe we can objectively identify those patients with chronic pain in whom the operation has been unsuccessful. A review of our experience with this procedure is presented along with criteria that enable early diagnosis of recurrent disease in the frontal sinus after osteoplastic sinusotomy.
13-cis-retinoic acid induces cellular differentiation and durable remission in refractory cutaneous Ki-1 lymphoma. A 35-year-old man with refractory cutaneous Ki-1 lymphoma was salvaged successfully with oral 13-cis-retinoic acid (1 mg/kg/day). He had a complete remission lasting for 20 months before a single nodule recurred on his skin. Excisional biopsy of the recurrent tumor revealed a distinct morphologic change, suggesting cellular differentiation toward a more benign phenotype. No significant side effects were noted except mild xerostomia, bone pain, and hyperlipidemia. The authors believe that 13-cis-retinoic acid should be considered in the treatment of cutaneous Ki-1 lymphoma.
Peritoneal seeding following potentially curative resection of colonic carcinoma: implications for adjuvant therapy. Adjuvant therapeutic strategies for colon cancer are based on the knowledge of tumor recurrence patterns following potentially curative resection. Innovative methods for regional delivery of chemotherapy to the liver and peritoneal surfaces are now available to complement systemic treatment. We reviewed clinical, reoperation, and autopsy series to determine the incidence of peritoneal seeding following colon cancer resection. The data suggest a 25-35 percent peritoneal failure rate among patients that recur, indicating that intraperitoneal chemotherapy is a sensible adjuvant approach. The theory behind intraperitoneal chemotherapy and potential complications is discussed. We suggest initiation of clinical trials combining systemic and intraperitoneal chemotherapy.
A case of granulomatous hepatitis after intravesical bacillus Calmette-Guerin administration. A 61-year-old man received intravesical bacillus Calmette-Guerin (BCG) as treatment for superficial bladder carcinoma. High spiking relapsing fevers began 39 days after the initial treatment. A liver biopsy revealed noncaseating granuloma. Deoxyribonucleic acid hybridization of the bone marrow was positive for Mycobacterium tuberculosis complex. Pressure exerted to instill the BCG may have favored dissemination.
Carotid duplex sonography: bisferious pulse contour in patients with aortic valvular disease. Characteristic systolic and diastolic pulse contours occur in the carotid Doppler waveforms of patients with aortic valvular disease that have not previously been described in publications concerning carotid duplex sonography. The purpose of this study was to evaluate the presence and characterize the nature of these carotid duplex waveform abnormalities in patients with known aortic valve disease and to correlate these changes with the severity of valve dysfunction. The study group consisted of 26 patients with aortic regurgitation or combined aortic regurgitation and aortic stenosis. Duplex studies were retrospectively reviewed by two radiologists for the presence of two systolic peaks, and for the presence of diastolic reversal of flow direction. This pattern of two systolic peaks, characteristic of aortic regurgitation, is called bisferious from the Latin "twice beating." Aortic regurgitation was graded by echocardiography as mild, moderate, or severe by the cardiologists reviewing the examination. A group of 20 age-matched patients without aortic valvular disease were similarly assessed. The bisferious pattern was demonstrated in 13 (50%) of 26 patients. Five (19%) of 26 patients had significant reversal of diastolic flow. Four patients were studied both before and after aortic valve replacement. Three had bisferious wave contours preoperatively; two of these also had diastolic reversal of flow. The fourth patient had retrograde flow in diastole without systolic contour abnormality. Postoperatively, all carotid waveforms were normal. None of the duplex waveforms in the control group demonstrated characteristic systolic or diastolic abnormalities. The bisferious waveform and retrograde diastolic flow are Doppler patterns associated with aortic valvular disease. These patterns are reversible after aortic valve replacement. While echocardiography remains the study of choice in the evaluation of suspected valvular dysfunction, up to one third of patients with aortic regurgitation may not have a detectable murmur. Therefore, identifying these patterns on carotid duplex examinations may provide clinically useful information and serve as a clue to previously unsuspected cardiovascular disease.
Systemic toxicity of ropivacaine during ovine pregnancy. Ropivacaine is a new amide local anesthetic structurally related to bupivacaine and mepivacaine. Its potency and duration of action are similar to those of bupivacaine but its therapeutic index may be greater. Since pregnancy enhances the cardiotoxicity of bupivacaine, the current study was devised to compare the toxicity of ropivacaine in chronically instrumented nonpregnant and pregnant ewes during continuous intravenous infusion of the drug at the rate of 0.5 mg.kg-1.min-1. In all animals, symptoms of local anesthetic toxicity occurred in the usual order--convulsions, hypotension, apnea, and circulatory collapse. There were no significant differences between the two groups of animals in the doses and plasma concentrations of ropivacaine associated with each toxic manifestations. For example, circulatory collapse occurred at a mean dose of 11.3 +/- 1.1 mg.kg-1 in nonpregnant and 12.4 +/- 0.9 mg.kg-1 in pregnant animals, with corresponding plasma concentrations of 7.3 +/- 0.3 and 9.6 +/- 2.1 micrograms.ml-1 (P = not significant). Protein binding of ropivacaine in the concentration range associated with toxic manifestations was similar in sera obtained from nonpregnant and pregnant ewes. In conclusion, ovine pregnancy does not enhance the systemic toxicity of ropivacaine, possibly because of an absence of gestation-related increase in the availability of free drug.