123rc/medical_text huggingface dataset:
Reproducibility of growth hormone testing procedures: a comparison between 24-hour integrated concentration and pharmacological stimulation. The purpose of this study was to compare the reproducibility of two approaches to the evaluation of GH secretion: the integrated concentration of GH (IC-GH), a physiological test of GH secretion, and pharmacological stimulation tests. IC-GH was determined in 40 poorly growing children twice within 4 weeks. The first and second IC-GH were highly correlated r = 0.859, P less than 0.001. One hundred and thirteen poorly growing children underwent pharmacological GH stimulation tests twice within 6 weeks. A moderate correlation was found between the first and second pharmacological test r = 0.524, P less than 0.01. Among the three pharmacological stimuli studied, clonidine (n = 81) had the highest reproducibility followed by arginine (n = 20), and insulin (n = 12). We conclude that IC-GH is more consistently reproducible than the GH response to repeated pharmacological stimulation.
Immunological differentiation between neuroborreliosis and multiple sclerosis. Neuroborreliosis, a tick-borne spirochaetosis of the central nervous system, is diagnosed by the presence of intrathecally synthesized Borrelia burgdorferi-specific antibodies. Multiple sclerosis and neuroborreliosis can show similarities in clinical symptoms as well as lymphocytic cell reactions and oligoclonal bands in the isoelectric focusing of cerebrospinal fluid. To differentiate between multiple sclerosis and neuroborreliosis we tested intrathecally synthesized IgM and virus antibodies. The IgM indices were higher for most of the neuroborreliosis patients studied than for those with multiple sclerosis, and cell counts were also significantly higher in the acute stage of the disease. In 84% of multiple sclerosis patients we were able to demonstrate intrathecal antibody production against measles, rubella or mumps virus. Neuroborreliosis patients had no intrathecal virus antibody synthesis. The specification of oligoclonal bands resulting from isoelectric focusing of cerebrospinal fluid with an ELISA for B. burgdorferi can further substantiate the diagnosis of neuroborreliosis or help to rule it out in multiple sclerosis patients with positive borrelia-specific serology.
Crural artery bypass with adjunctive arteriovenous fistula. A modification in distal anastomosis. We carried out crural artery bypass with an adjunctive arteriovenous fistula in 8 lower extremities of 7 patients with severe ischemic symptoms and poor distal run-off. Mean blood flow rates in the implanted grafts ranged from 43 to 340 ml/min and those of the reconstructed crural arteries from 20 to 100 ml/min. A stenotic lesion was noted on postoperative angiogram in one patient and stasis symptoms caused by downward blood flow into the distal veins in another. The other patients have remained well with good function of the grafts 1-5 years after surgery. We modified the distal corner of the anastomosis as follows: three additional interrupted simple sutures were made on the anterior wall of the concomitant arteriotomy and venotomy incisions after making the common posterior wall of the vessel incisions. A vascular pocket formed at the distal corner of the anastomosis prevents stricture at the anastomosis. The vein is finally ligated just distal to the fistula to intercept downward blood flow into the distal veins. This modification in technique is recommended to prevent stricture of the distal anastomosis and postoperative stasis symptoms.
Retinal infarction during sleep and wakefulness. Brain and retinal infarctions during sleep have been attributed to focal hypoperfusion caused by systemic hypotension combined with underlying arterial stenosis, rather than to embolism. Because some retinal emboli may be visualized on ophthalmoscopy, we studied 24 consecutive patients (18 men and six women) aged 26-78 (mean 58) years with recent retinal infarction and determined whether the infarction had occurred during sleep or wakefulness. All patients underwent dilated ophthalmoscopy and a carotid artery study (arteriography in 20, duplex ultrasound in the remaining four), and 12 had echocardiography. Retinal infarction occurred during sleep at an unexpectedly rate (14 of 24 observed compared with eight of 24 expected, p = 0.02). Retinal cholesterol emboli were seen in one half of the patients regardless of whether the retinal infarction had occurred during sleep or wakefulness. Carotid artery disease was found in seven of the 14 patients in whom infarction had occurred during sleep and in eight of the 10 patients in whom infarction had occurred during wakefulness (p = 0.21). Cerebrovascular occlusive disease was not found in the five patients aged less than 50 years. Our findings suggest that embolism is a common mechanism of retinal infarction during sleep or wakefulness, that in patients aged greater than 50 years extracranial carotid artery disease is a common source of retinal emboli, and that the retina may be especially susceptible to infarction during sleep.
Thromboxane A2 biosynthesis in acute asthma and after antigen challenge. Thromboxane A2 is a potent bronchial smooth muscle spasmogen in vitro, and it has been implicated in airway inflammation and in the genesis of bronchial hyperresponsiveness in asthma. We have examined the urinary excretion of a variety of products derived from thromboxane A2 (thromboxane B2, 2,3-dinor, and 11-dehydro-thromboxane B2) and prostacyclin (6-oxo-PGF1 alpha and 2,3-dinor-6-oxo-PGF1 alpha) using gas chromatography-mass spectrometry in patients admitted acutely to hospital with severe asthma and in atopic volunteers after bronchial antigen challenge. Urinary excretion of all thromboxane-derived products was markedly increased in a number of patients with severe acute asthma compared with that in a nonsmoking control population, in some cases approaching those previously described in myocardial infarction: TXB2, 31.6 +/- 12.0 versus 6.5 +/- 0.9; 2,3-dinor-TXB2, 79.0 +/- 19.2 versus 29.5 +/- 2.7; and 11-dehydro-TXB2, 234.3 +/- 65.3 versus 25.0 +/- 2.1 ng/mmol creatinine (p less than 0.001). Urinary prostacyclin-derived products were also significantly raised in acute asthma. In contrast, after inhaled allergen challenge in atopic volunteers, which caused significant bronchoconstriction, urinary excretion of thromboxane-derived products was not significantly elevated: TXB2, 5.6 +/- 1.1 versus 5.7 +/- 1.0; 2,3-dinor-TXB2, 41.2 +/- 12.5 versus 28.5 +/- 6.9; and 11-dehydro-TXB2, 69.8 +/- 17.6 versus 39.7 +/- 11.2 ng/mmol creatinine. In a separate experiment, less than 2% of exogenously administered TXB2 to the airway appeared as urinary thromboxane-derived products, suggesting that production of greater than or equal to 1 microgram of TXA2 in vivo would be required to increase urinary thromboxane excretion twofold.
A forme fruste of Marfan's syndrome: case history. A thirty nine year old woman presented with multiple aneurysms and dissections of the arterial system secondary to cystic medial necrosis is presented. After assessment of the family history a diagnosis of a forme fruste of Marfan's syndrome was made. Preoperative consideration of this rare diagnosis is important for treatment and surgical management.
Effects of doxazosin on serum lipids: a review of the clinical data and molecular basis for altered lipid metabolism. The goal of antihypertensive treatment must be not only the reduction of high blood pressure, but also the effective management of elevated cholesterol levels and other risk factors of coronary heart disease (CHD). In controlled clinical trials, doxazosin has been shown to have antihypertensive efficacy comparable with other classes of antihypertensive agents and to lower the levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides while increasing the levels of high-density lipoprotein cholesterol. Doxazosin appears to inhibit the development of CHD on two fronts. First, doxazosin binds to the alpha 1-adrenoreceptor and inhibits the receptor-mediated responses to epinephrine and norepinephrine. Second, doxazosin has direct and indirect effects on lipid metabolism by increasing LDL receptor activity, decreasing intracellular LDL synthesis, reducing the synthesis and secretion of very low-density lipoprotein cholesterol, and stimulating lipoprotein lipase activity. Doxazosin may also inhibit platelet aggregation. Long-term studies will determine how these actions translate into reductions in the morbidity and mortality rates of CHD. First-year results from the Treatment of Mild Hypertension Study (TOMHS) have demonstrated expected reductions in blood pressure for all antihypertensive agents studied. The lipid changes have varied with the type of antihypertensive treatment and have been favorable for doxazosin.
Expression of insulin-like growth factor II, alpha-fetoprotein and hepatitis B virus transcripts in human primary liver cancer. Insulin-like growth factor II is a fetal growth factor structurally and functionally related to insulin and insulin-like growth factor I. Its mRNA expression is developmentally regulated in human liver, the reexpression of insulin-like growth factor II fetal transcripts being often observed in primary liver cancer. Insulin-like growth factor II and alpha-fetoprotein mRNAs were studied in 16 human primary liver cancers, most of which were highly differentiated. Hepatitis B virus transcripts were also analyzed in the tumors from hepatitis B virus chronic carriers. alpha-Fetoprotein mRNA was detected in only four tumors and in one nontumorous cirrhotic tissue; all these samples also displayed insulin-like growth factor II fetal transcripts. Furthermore, fetal insulin-like growth factor II mRNAs were observed in five tumors and six nontumorous cirrhotic areas not expressing alpha-fetoprotein mRNA. The presence of hepatitis B virus RNA was only observed in tissues not expressing alpha-fetoprotein or fetal insulin-like growth factor II mRNA. In conclusion, fetal insulin-like growth factor II transcripts are more frequently observed than alpha-fetoprotein mRNA in highly differentiated liver cancers and in surrounding cirrhotic areas. The reexpression of fetal insulin-like growth factor II transcripts might then be a marker of early steps of liver cell transformation.
Risk of myocardial infarction and death during treatment with low dose aspirin and intravenous heparin in men with unstable coronary artery disease. The RISC Group 796 men with unstable coronary artery disease (unstable angina or non-Q-wave myocardial infarction [MI] ), were randomised to double-blind placebo-controlled treatment with oral aspirin 75 mg/day and/or 5 days of intermittent intravenous heparin. The risk of MI and death was reduced by aspirin. After 5 days the risk ratio was 0.43 (confidence intervals, 0.21-0.91), at 1 month 0.31 (0.18-0.53), and at 3 months 0.36 (0.23-0.57). Aspirin reduced event rate in non-Q-wave MI and unstable angina, independently of electrocardiographic abnormalities or concurrent drug therapy. Heparin had no significant influence on event rate, although the group treated with aspirin and heparin had the lowest number of events during the initial 5 days. Treatment had few side-effects and high patient compliance.
Coronary arterial remodeling studied by high-frequency epicardial echocardiography: an early compensatory mechanism in patients with obstructive coronary atherosclerosis. Coronary arterial remodeling is a compensatory mechanism that may limit the adverse effects of coronary obstructive lesions by expansion of the entire vascular segment. To determine if this compensatory anatomic change occurs in patients, high-frequency epicardial echocardiography using a 12 MHz transducer was performed during open heart surgery in 33 patients (10 with normal coronary arteries undergoing valvular surgery and 23 with coronary atherosclerosis). From stop-frame videotape high-frequency epicardial echocardiographic images, cross-sectional measurements of luminal area and total arterial area (lumen, intima, media and dense adventitia) were made in the patients with atherosclerosis at the site of arterial lesions and from the most proximal portion of the same artery. Remodeling was defined as enlargement of the total arterial area. In normal arteries measurements were made from proximal and midarterial locations. In the patients with normal coronary arteries, total arterial area, as determined by high-frequency echocardiography, decreased from the proximal site to the midportion of the artery (from 10.4 +/- 0.9 to 8.4 +/- 1.0 mm2, p less than 0.05); luminal area also decreased (from 6.0 +/- 0.6 to 4.5 +/- 0.7 mm2, p less than 0.05). In patients with coronary arterial lesions, luminal area also decreased from the proximal site to the arterial lesion site (from 5.3 +/- 0.6 to 2.3 +/- 0.3 mm2, p less than 0.05), but total arterial area increased (from 11.6 +/- 1.0 to 13.0 +/- 1.0 mm2, p less than 0.05). Of the 25 coronary arteries evaluated, only 4 had angiographic evidence of coronary collateral formation. These data indicate that coronary arterial remodeling is an important compensatory mechanism in obstructive coronary disease.
Pyloric deformation from peptic disease. Radiographic evidence for incompetence rather than obstruction. We have used double-contrast radiographic techniques to clarify what changes in the configuration and movements of the gastroduodenal junction result when peptic lesions involve the distal gastric segment between the proximal (PPL) and the distal pyloric muscle loop (DPL). Among 50 cases of pyloric ulceration diagnosed during a four-year study period, 18 cases fulfilled all study criteria. Ulcers maintained a consistent location with regard to the muscular structures of the pylorus, and by affecting these structures, led to many strange deformations of the gastric outlet including permanent pseudodiverticula and reversal of pyloric angulation. The most common site for peptic lesions in the pyloric segment was the protuberance of the lesser curvature called the pyloric torus; many torus lesions extended into and destroyed the DPL. This led to widening of the gastric outlet and radiographic evidence of increased duodenogastric reflux. Pyloric closure was further impaired in this setting because the mucosa no longer prolapsed into the gastric outlet and did not occlude the pyloric lumen as it normally does. Less common lesions involved the greater curvature and the PPL. In one patient, scarring of the PPL led to an antral web and gastric hyperperistalsis. This was the only patient who required operation for chronic gastric outlet obstruction. One-third of the 18 patients had reflux esophagitis in addition to peptic pyloric disease. In most patients without additional ulcerogenic risk factors, treatment with antisecretory agents led to the healing of ulcer craters. We conclude that the morphologic and functional changes of the gastric outlet caused by peptic lesions depend, in part, on the effect the ulcer has on the underlying pyloric musculature.
Evidence against leukotrienes as mediators of brain edema. Leukotrienes are powerful metabolites of arachidonic acid which are known to increase the permeability of peripheral blood vessels. These substances are found in brain tissue in association with cerebral ischemia, and in brain tumors. Therefore, it has been proposed that leukotrienes have a mediator function in brain edema. This hypothesis was subjected to further experimental analysis in this study, in which the authors investigated whether: 1) superfusion of the exposed brain surface with leukotrienes increases the permeability of extraparenchymal blood vessels in vivo; 2) intraparenchymal infusion of leukotrienes induces brain edema; and 3) pharmacological inhibition of leukotriene formation by BW755C, an inhibitor of leukotriene synthesis, reduces formation of brain edema from a standardized traumatic insult. The pial vessels of the parietal cortex of cats were examined by fluorescence microscopy during cerebral superfusion with the leukotrienes C4 (LTC4), D4 (LTD4), or E4 (LTE4) by using an open cranial window preparation. Intravenous Na(+)-fluorescein served as an in vivo blood-brain barrier (BBB) indicator. Superfusion of the pia with leukotrienes (up to 2 microM) did not open the barrier to fluorescein, but was associated with a significant constriction (up to 25%) of arterial and venous vessels. In experiments with slow infusion of leukotriene B4 (LTB4) or LTC4 into the white matter of feline brain, the tissue water content was subsequently determined in serial brain slices using the specific gravity method. Tissue water profiles obtained after a 15-microM infusion of either LTB4 or LTC4 were virtually identical with those of control animals infused with mock cerebrospinal fluid. Thus, neither LTB4 nor LTC4 led to an augmentation of infusion-induced brain edema. In a final series, a cold lesion of the left parietal cortex was induced in rabbits. Twenty-four hours later, swelling of the exposed hemisphere was quantified by gravimetrical comparison of its weight with that of the contralateral nontraumatized hemisphere. Eight animals received BW755C intravenously prior to and after trauma to inhibit formation of leukotrienes. Seven rabbits were infused with an equivalent volume of saline as a control study. The resulting hemispheric swelling was 7.7% +/- 0.6% (mean +/- standard error of the mean) 24 hours later in animals receiving BW755C and 7.8% +/- 1.2% in the control group, indicating that inhibition of leukotrienes was ineffective in preventing formation of vasogenic brain edema. The findings demonstrate that leukotrienes administered to the brain in concentrations occurring under pathological conditions do not open the BBB nor do they induce brain edema.(ABSTRACT TRUNCATED AT 400 WORDS).
Effects of felodipine on urinary albumin excretion and metabolic control in hypertensive non-insulin-dependent diabetics. The effect of a blood pressure reduction by 10 mg extended release felodipine once daily on urinary albumin excretion (UAE) as well as the possible diabetogenic effect of felodipine was studied. A 2 X 12 week placebo-controlled double-blind crossover study was performed in 12 hypertensive non-insulin-dependent diabetic (NIDDM) patients without nephropathy on concomitant treatment with beta-blocker and/or a diuretic agent. Metabolic control as estimated by fasting plasma glucose, hemoglobin A1c and fasting plasma C-peptide was unaltered after felodipine. Blood pressure was significantly reduced by felodipine: systolic 166 +/- 26 mm Hg (placebo) v 153 +/- 26 mm Hg (felodipine) (P less than .05) and diastolic 95 +/- 7 mm Hg v 90 +/- 8 mm Hg (P less than .05). Heart rate was unchanged. There was no correlation between blood pressure and UAE, but the relative change in UAE expressed as UAE placebo/UAE felodipine was significantly correlated to the fall in systolic blood pressure (r = 0.64, P = .03) and mean blood pressure (r = 0.66, P = .02). Since microalbuminuria predicts proteinuria and reduced survival, early antihypertensive treatment may be beneficial in NIDDM as it is in IDDM. Long-term consequences on kidney function and mortality remains, however, to be elucidated.
Activation of early events of the mitogenic response by a P2Y purinoceptor with covalently bound 3'-O-(4-benzoyl)-benzoyladenosine 5'-triphosphate. 3'-O-(4-Benzoyl)benzoyl-ATP (BzATP), a photoaffinity analog of ATP, was used as a ligand for a P2Y purinoceptor (adenine nucleotide receptor) present in intact Swiss 3T3 and 3T6 cells and A-431 epidermoid carcinoma cells. Photolysis of serum-starved cells in the presence of 10-50 microM BzATP, followed by extensive washing to remove unincorporated BzATP, induced the release of arachidonic acid. A trace (less than 0.01%) of photoincorporated BzATP was as effective as when 50 microM BzATP or ATP was contained in the incubation medium during the assay. Photoincorporated BzATP also stimulated the production of prostaglandin E2 and the accumulation of cyclic AMP. In previous studies, we demonstrated that these three events are obligatory early steps in a pathway leading to DNA synthesis in the above cell lines. The evidence indicated that the purinoceptor activated by extracellular ATP or BzATP was linked to a pertussis toxin-sensitive GTP-binding protein. Consistent with these observations, we now find that pertussis toxin inhibits the effect of photoincorporated BzATP on arachidonic acid release. These results indicate that BzATP is an effective agonist for the P2Y purinoceptor concerned with stimulation of DNA synthesis in 3T3, 3T6, and A-431 cells. Furthermore, after photolysis it becomes irreversibly associated with intact cells and promotes the activation of early events required for DNA synthesis.
Xeroderma pigmentosum: review and report of a case. Xeroderma pigmentosum is a rare inherited dermatosis that provides insight into the basic mechanism of carcinogenesis. It is a model disorder linking defective DNA repair with clinical abnormalities and neoplasia. UV light-induced damage to the skin begins early and results in multiple benign and malignant skin tumors, especially in sun-exposed areas of the head and neck. Oral cancers, primarily squamous cell carcinomas of the anterior third of the tongue, occur with greatly increased frequency. A patient with multiple facial neoplasia and oral manifestations of xeroderma pigmentosum is presented. The role of the dentist in surveillance of oral and perioral structures is emphasized. The dentist is advised against the use of UV light-curing units in these patients because UV-induced epithelial damage may cause dysplasia when DNA repair mechanisms are dysfunctional.
Thallous chloride uptake and DNA profile in parathyroid adenomas. Thallium isotope scintigraphy is used to localize parathyroid adenomas but the mechanism underlying the technique is poorly understood. While larger adenomas are reliably localized the results are less certain for small tumours. This study explores the relationship between cellular DNA profile and thallium uptake (localization accuracy) in 24 parathyroid adenomas. The DNA profile was assessed using flow cytometry and standard subtraction thallium scintigraphy was performed before surgery. Fifteen of the 24 adenomas demonstrated excessive mitotic activity and 13 of these glands were accurately localized. Of the remaining nine glands, only five were localized accurately (P less than 0.01, chi 2 test including Yates' correction). This difference in thallium uptake could not be accounted for on the basis of gland weight. Thallium localization of parathyroid adenomas is related to mitotic activity. This may explain some of the limitations of this technique.
Primary abscess of the omentum. A 65-yr-old man presented with upper abdominal pain and fever due to a primary abscess of the omentum. The finding of microscopic-size foreign particles within the abscess raised the possibility of antecedent clinically silent perforation of the bowel or appendix. Surgical resection and antibiotic therapy were curative.
Lesions of the mid-shaft of the humerus presenting as shoulder capsulitis. We describe three patients who presented with pain and restriction of movement at the shoulder suggestive of capsulitis, but proved to have lesions of the mid-shaft of the humerus. It is important to be aware of the possibility of this cause of a 'frozen shoulder', since radiographs of the shoulder are usually cropped at the mid-humerus and lesions at this level may easily be missed. A radiograph of the entire humerus, or an isotope bone scan, may be more useful than repeated shoulder radiographs in patients whose shoulder symptoms do not respond to standard treatment.