123rc/medical_text huggingface dataset:
Physiologic responses to prolonged electrically stimulated leg-cycle exercise in the spinal cord injured. This study determined the physiologic responses to prolonged functional neuromuscular stimulation (FNS) leg-cycle exercise in seven quadriplegic and seven paraplegic subjects. Each subject completed 30 minutes of continuous FNS leg cycling during which open-circuit spirometry, impedance cardiography, auscultation, and fingertip capillary blood sampling were used to assess metabolic and hemodynamic responses. Compared with resting values, oxygen uptake, carbon dioxide production, respiratory exchange ratio (RER), pulmonary ventilation, heart rate (HR), left ventricular stroke volume (SV), cardiac output (Qt), and blood lactate (La) concentration were significantly (p less than .05) elevated, whereas plasma volume, bicarbonate concentration, and pH were significantly decreased in both groups during prolonged FNS leg-cycle exercise. Mean arterial pressure remained unchanged in quadriplegic and paraplegic subjects during the prolonged FNS leg-cycle exercise bout. Persons with quadriplegia elicited significantly lower MAP and tended to have lower SV and Qt responses than persons with paraplegia, probably due to a higher degree of sympathetic dysfunction and circulatory hypokinesis during FNS leg-cycle exercise. All other physiologic variables responded similarly between groups. We speculate that the relative increases observed for HR (33% to 60%), SV (45% to 69%), and Qt (113% to 142%) during prolonged FNS leg-cycle exercise create a sufficient cardiac-volume load to promote central cardiovascular conditioning in persons with both quadriplegia and paraplegia. The La accumulation (4.7 to 5.2 mmol.L-1) in the spinal cord injured during prolonged FNS leg cycling is unusually high for the power output attained (5.2W and 6.1W for quadriplegia and paraplegia, respectively).
Effects of two types of fish oil supplements on serum lipids and plasma phospholipid fatty acids in coronary artery disease. Fish oil has consistently been shown to lower triglyceride levels, but its effects on low-density lipoprotein (LDL) cholesterol remain controversial. The current study compares the long-term effects of 2 different fish oil preparations (ethyl ester and triglyceride) versus olive oil in patients with coronary artery disease. Eighty-nine subjects were randomly assigned to receive capsules containing 6 g/day (triglyceride group) or 7 g/day (ethyl ester group) of n-3 fatty acids, or capsules containing 12 g/day of olive oil for 6 months. Mean triglyceride levels decreased by 28% in the ester and 32% in the triglyceride fish oil groups (p less than 0.05 for both). LDL cholesterol levels increased by 3% (difference not significant) in the ester and 12% (p less than 0.05) in the triglyceride fish oil groups; in hypertriglyceridemic subjects the increase was 23% (p less than 0.01) and 14% (difference not significant), respectively. Plasma phospholipid fatty acid analysis showed a fivefold increase in eicosapentaenoic acid levels in both fish oil groups (p less than 0.001), and a long-term decrease in arachidonic acid levels (p less than 0.001). Achieved eicosapentaenoic acid level correlated with the degree of increase in LDL cholesterol (r = 0.38, p less than 0.05). These data suggest that fish oil administration is associated with an increase in LDL cholesterol levels in a diverse group of patients with coronary artery disease; this change appears to be correlated with n-3 fatty acid absorption. The impact of this increase in LDL is unknown, but should be considered as potentially adverse.
Association between neuroepithelial tumor and multiple intestinal polyposis (Turcot's syndrome): report of a case and critical analysis of the literature. We report a case of association of a brain tumor with multiple intestinal polyposis (Turcot's syndrome) and offer a critical analysis of the relevant literature with a view to revising the classification of the syndrome in relation to familial multiple polyposis and Gardner's syndrome. For this purpose, we considered only cases of intestinal polyposis associated with a primary neuroepithelial tumor (medulloblastoma, glioma, or glioblastoma) as originally described by Turcot. Differences emerged, depending on the central nervous system tumor type, which suggests that this neoplastic association may be classified as two distinct syndromes.
Balloon expandable stent implantation in stenotic right heart valved conduits. Although valved conduits have been used successfully in severe forms of right ventricular-pulmonary artery discontinuity, progressive valved conduit stenosis is an important clinical problem. To determine the feasibility of reducing right heart valved conduit stenosis with a balloon expandable stent, a baboon model was used, in which the pulmonary artery was ligated and a right ventricular to pulmonary artery 14 mm bioprosthetic Dacron valved conduit implanted. In five baboons, at an average of 40 months after valved conduit implantation, fibrointimal stenosis at the valve site resulted in narrowing and a mean transconduit pressure gradient of 49 mm Hg (range 33 to 65). A tubular slotted steel stent (1.2 cm long) was deployed within the valved conduit after inflation of an 8 to 15 mm diameter balloon catheter that was introduced through the femoral vein. A stent was delivered to all valved conduits; however, in two baboons, balloon undersizing resulted in stent dislodgment. In the remaining three baboons, the transconduit gradient was reduced by 59% (49 to 20 mm Hg) and right ventricular systolic pressure decreased acutely by 35% (77 to 50 mm Hg). It is concluded that stent deployment is feasible in right ventricular to pulmonary artery stenotic valved conduits and may result in significant hemodynamic improvement. However, successful stent delivery is critically dependent on the proper selection of stent length and balloon diameter.
Hemodynamic effects of nebivolol at rest and on exertion in patients with heart failure. Nebivolol is a novel B-1-adrenoceptor-blocking drug with an unusual hemodynamic profile unlike classical B-blockers. In dogs and in healthy volunteers it decreases blood pressure and heart rate but improves left ventricular function. The authors studied 10 male patients with coronary artery disease and heart failure (ejection fraction mean = 46%). A Swan-Ganz catheter was placed into the pulmonary artery, and the mean blood pressure, the heart rate, the pulmonary artery pressure, the pulmonary wedge pressure, the right atrial pressure, the cardiac output, and the stroke volume were measured at rest and on exertion before and after seven days' treatment with oral nebivolol (5 mg/day). While the blood pressure and the heart rate decreased significantly, the pulmonary artery and wedge pressures, as well as the right atrial pressure and the cardiac output, did not change during treatment. The stroke volume increased significantly. The maintained cardiac output cannot be explained by any changes in preload or afterload; instead a positive inotropic mechanism must be assumed. Unlike other B-blockers it seems to be possible to treat patients with heart failure with nebivolol without causing the hemodynamic situation to deteriorate.
Progressive inflammatory lesions of the brain parenchyma in localized scleroderma of the head. A patient with localized scleroderma of the head, uveitis, and Raynaud's phenomenon presented with generalized seizures, spastic hemiparesis, and local IgG production in the cerebrospinal fluid. Magnetic resonance imaging revealed progressive cortical and subcortical brain parenchymal lesions mainly adjacent to the cutaneous and bony lesions and probably of inflammatory origin.
Acute arsenical myopathy: morphological description. We describe the histological findings of the muscle in a case of acute voluntary massive arsenic intoxication resulting in severe rhabdomyolysis. The main features on muscle biopsy were perifascicular hypercontracted fibers, myofibrillar disruption, mitochondrial abnormalities and abundant cytoplasmic vacuoles containing lipids.
Assessment of cataracts from photographs in the Beaver Dam Eye Study. Presence and severity of age-related cataract was determined in adults 43 to 84 years of age in Beaver Dam, Wisconsin. Duplicate photograph gradings for nuclear sclerosis (n = 1160), cortical opacities (n = 1159), and posterior subcapsular cataract (n = 1137) were performed. There are five levels of nuclear sclerosis. Exact agreement occurred in 64.7% of the cases; agreement within one category in 99.8%. For cortical opacities, graders estimate involved area in nine segments of the lens. When the continuous scale is divided into 12 categories of severity, exact agreement varied between 73.5 and 82.4%; for agreement within one category, rates varied between 84.6 and 89.9%. For posterior subcapsular cataracts, exact agreement for involvement of the central circle occurred in 95.0% and agreement within one category occurred in 97.7%. Intraobserver comparisons disclosed similar concordance. These grading schemes are semiquantitative, reproducible, and can be performed for the large numbers of photographs from population-based studies.
Randomized, double-blind, placebo-controlled trial of somatostatin for variceal bleeding. Emergency control and prevention of early variceal rebleeding. A randomized, double-blind, placebo-controlled trial of somatostatin was conducted among 120 patients admitted for bleeding esophageal varices (59 placebo, 61 somatostatin). An initial 250-micrograms bolus of somatostatin followed by a 5-day continuous infusion of 250 micrograms/h and an identical administration of placebo were evaluated for both the control of bleeding and prevention of early rebleeding from varices. Failure to control bleeding occurred in 22 (36%) somatostatin patients vs. 35 (59%) placebo patients, with time to failure occurring earlier with placebo (P = 0.036). blood and plasma transfused per hour during drug infusion of trial drug was reduced in the somatostatin group: median 0.033 vs. 0.105 unit/h (P = 0.025). Use of balloon tamponade was halved in somatostatin-treated patients. The average effect of somatostatin was a 41% reduction in the hazard of failure (95% confidence interval, -1% to 65%, P = 0.0545) after adjustment for the severity of liver disease, which was the only other variable having a significant influence on time to failure. There was no difference in 30-day mortality per admission (7 placebo, 9 somatostatin) or complications. It is concluded that somatostatin is safe and more effective than placebo for the control of variceal bleeding.
Effect of pentoxifylline on hemodynamics, alveolar fluid reabsorption, and pulmonary edema in a model of acute lung injury. We investigated the effect of pentoxifylline (PTX) on the development of pulmonary edema in a model of adult respiratory distress syndrome in rabbits. Lung injury was induced by repeated saline lavages in adult rabbits weighing 2.5 to 3.5 kg. Rabbits pretreated with PTX (20 mg/kg bolus followed by 20 mg/kg/h infusion) developed significantly lower amounts of lung edema 4 h after saline lavage (extravascular lung water to dry weight ratio [W/D], 6.9 +/- 0.6 SD versus 8.9 +/- 0.5 in control animals). PTX produced a 25% increase in cardiac output, but there were no differences between treated and untreated groups in calculated pulmonary vascular resistance or microvascular pressure. To determine whether PTX could have lowered pulmonary venous resistance and thus lowered effective microvascular pressure for fluid filtration, we directly measured pulmonary artery and left atrial pressures, and measured by micropuncture the pressure in 20 to 40 microns subpleural venules in four open-chested rabbits 3 to 4 h after lavage. Venous resistance was low (venous pressure drop 0.9 +/- 0.1 mm Hg) and was unchanged by PTX infusion. To determine if PTX decreased lung water by accelerating active alveolar fluid reabsorption, a single 60-ml aliquot of saline was instilled into the lungs of normal rabbits treated with saline or PTX. Both groups had a similar decrease in lung water content 1 and 4 h later. Our data indicate that PTX reduces edema formation in rabbits after saline lavage, not by lowering microvascular pressures for fluid filtration or by acceleration alveolar fluid reabsorption, but possibly by its anti-inflammatory effect on neutrophil function.
Management of postoperative inflammation: dexamethasone versus flurbiprofen, a quantitative study using the new Flare Cell Meter. A consecutive, random, prospective study was conducted to compare the effect of topical dexamethasone and flurbiprofen drops on postoperative inflammation in patients undergoing extracapsular cataract extraction with lens implantation. Objective, quantitative measurements were made postoperatively, using the Kowa FC-1000 Flare Cell Meter. The two treatments were equally effective.
Infectious mononucleosis in older adults. Infectious mononucleosis as a manifestation of primary Epstein-Barr virus infection occurs uncommonly in adults over age 40. While fever is almost universal, older patients with the disease often present without lymphadenopathy, pharyngitis, splenomegaly, lymphocytosis or atypical lymphocytes. Jaundice and hepatomegaly occur more commonly in older patients than in adolescents and create diagnostic confusion. Often, infectious mononucleosis in this age group is confused with lymphoma, leukemia or biliary obstruction, or is classified as "fever of unknown origin.".
Transient hyperprolactinemia is associated with a midcycle luteinizing hormone surge. This study demonstrates that LH surge cycles in IVF patients were associated with significantly higher serum PRL concentrations than cycles in which a spontaneous LH surge did not occur. Our findings support the hypothesis of concomitant LH and PRL release at the time of the midcycle gonadotropin surge, as well as that of estrogen sensitization of pituitary lactotropes, and suggest a possible mechanism for transient midcycle hyperprolactinemia.
Comparison of pulse oximeters: accuracy at low arterial pressure in volunteers. A laboratory model was developed of limb hypoperfusion in volunteers, using parital occlusion of the brachial artery with consequent reduction in radial artery pulse pressure. This was used to compare the function of 13 pulse oximeters and the effect of reduced pulse pressure and mild hypoxia on these devices. With the exception of one device, all the pulse oximeters studied demonstrated similar accuracies at pulse pressures exceeding 20 mm Hg. There were however, significant differences between several of the pulse oximeters in both ability to display readings and accuracy of readings displayed when brachial artery occlusion reduced radial artery pulse pressures equal to or less than 20 mm Hg.
Predicting the severity of cocaine-associated rhabdomyolysis. STUDY OBJECTIVES: The syndrome of rhabdomyolysis associated with cocaine use has been recently described, but the incidence, severity, risk factors, and complications are unknown. This study sought to describe the spectrum of the syndrome and identify clinical features of patients at risk. DESIGN: Retrospective case series with analysis of common clinical features. SETTING: Medical emergency department of an urban teaching hospital serving an indigent population. TYPES OF PARTICIPANTS: ED patients with acute cocaine intoxication and a serum creatine kinase (all MM) of more than 500 U/L (8.3 ukat/L) who were admitted for in-hospital management. MEASUREMENTS AND MAIN RESULTS: Twenty-nine patients, representing 5% of cocaine-related patient visits, were identified over 20 months. Patients were divided into three groups: mild, characterized by anxiety, tachycardia, diaphoresis, dyspnea, or chest pain; moderate, characterized by delirium, agitation, fever, leukocytosis, or an elevated serum creatinine; and severe, characterized by seizure, coma, hypotension, arrhythmia, or cardiac arrest. There was a significant association between the rating system for level of intoxication and the severity of rhabdomyolysis and its complications (P less than .01). Patients at highest risk for complications of rhabdomyolysis were those in the moderate or severe groups. CONCLUSION: This classification system may be useful for the management of patients with acute cocaine intoxication, predicting those patients in whom aggressive therapy should be initiated in the ED to minimize the complications of rhabdomyolysis.
Distribution of pulmonary capillary transit times in recruited networks. When pulmonary blood flow is elevated, hypoxemia can occur in the fastest-moving erythrocytes if their transit times through the capillaries fall below the minimum time for complete oxygenation. This desaturation is more likely to occur if the distribution of capillary transit times about the mean is large. Increasing cardiac output is known to decrease mean pulmonary capillary transit time, but the effect on the distribution of transit times has not been reported. We measured the mean and variance of transit times in single pulmonary capillary networks in the dependent lung of anesthetized dogs by in vivo videofluorescence microscopy of a fluorescein dye bolus passing from an arteriole to a venule. When cardiac output increased from 2.9 to 9.9 l/min, mean capillary transit time decreased from 2.0 to 0.8 s. Because transit time variance decreased proportionately (relative dispersion remained constant), increasing cardiac output did not alter the heterogeneity of local capillary transit times in the lower lung where the capillary bed was nearly fully recruited.
Arteriovenous fistula as a complication of temporary pacemaker insertion: treatment with percutaneous embolization. Arteriovenous fistula is a rare complication of central venous catheterization. We present a case of right internal mammary artery-to-right innominate vein fistula resulting from emergent insertion of a temporary pacemaker. Percutaneous management is discussed and the literature is reviewed.
Hypereosinophilic syndrome with unusual cutaneous manifestations in two men with HIV infection. We report two men with human immunodeficiency virus infection who had unusual cutaneous manifestations of hypereosinophilic syndrome, exfoliative erythroderma, and linear flagellate plaques. In the first patient the cutaneous disease was the initial manifestation, and in the second the skin was the only organ affected. We also describe a favorable response to systemic corticosteroids and to psoralen with UVA phototherapy in one patient.
Metastatic melanoma to the facial nerve. Isolated metastatic malignant melanoma to the facial nerve has never been reported. This presentation illustrates a primary melanoma of the helix of the ear that was treated by excisional biopsy and then wedge resection in 1983. The primary melanoma was Clark's level IV and 1.3 mm in thickness. In 1985, a facial paresis slowly developed. There was no gross evidence of recurrent melanoma in the ear or neck, but CT scan showed a mass in the region of the stylo mastoid foramen. A reoperation of the primary site revealed metastatic melanoma in the facial nerve, expanding it to approximately 10 times its normal size. A composite resection was done for the melanoma, and the paralyzed face was immediately rehabilitated by a masseter muscle transfer. The patient received 6000 rads to this area postoperatively and has remained free of disease to date, having returned to his profession as a dentist. A detailed study of all the specimens indicated that this represented a primary metastasis to the facial nerve.
Fasciculations due to verapamil in a patient with neuropathy. A patient with pre-existing peripheral neuropathy developed generalized fasciculations under verapamil which ceased after discontinuation of the drug. It is suggested that the increase in acetylcholine (ACh) release at the neuromuscular junction by verapamil may trigger fasciculation in the state of regeneration at ACh-sensitive sites of axon terminals and immature axon sprouts.
Impairment of specific host defense mechanisms in patients with chronic post-traumatic osteomyelitis. We studied both in vivo and in vitro specific host defense mechanisms in patients suffering from chronic post-traumatic osteomyelitis (n = 26). The cell-mediated immunity in vivo was impaired as indicated by the reduced reactivity in the delayed type hypersensitivity skin test. The concanavalin A or phytohemagglutinin-induced T-cell proliferation in vitro was markedly decreased in comparison to healthy donors. In contrast, B-cell proliferation stimulated by Staphylococcus aureus Cowan I was not altered. While the absolute lymphocyte counts and the percentage of T, B, and O cells were within the normal range, nine out of the 26 patients showed a significantly diminished ratio of CD4+ and CD8+ T cells. Humoral immunity in the patients was less affected as assessed by the unchanged serum levels of immunoglobulins (Ig). However, the T-cell dependent polyclonal Ig synthesis after in vitro stimulation with pokeweed mitogen was suppressed. Our results provide evidence that cell-mediated immune functions are predominantly impaired in patients with post-traumatic osteomyelitis which may contribute to the persistence of the localized bone infection.
Carcinoma of the external auditory canal: an update. This review is a continuation of the series of 35 cases of carcinoma of the external auditory canal originally reported by the senior author and colleagues. Eighteen additional cases have been evaluated and treated since 1976. Preoperative high-resolution computed tomographic scanning has replaced polytomography, and improved surgical skull base approaches have allowed for extended resections of advanced lesions. A revised classification for local and extensive lesions is presented. The prognosis for localized tumors treated by en bloc resection remains excellent, whereas prognosis for extensive lesions might be more dependent on histologic type and grade of tumor.
Effects of bepridil and diltiazem on ventricular repolarization in angina pectoris. To examine the time-course and potential predictors of prolongation of ventricular repolarization with the calcium antagonist bepridil, the effects of bepridil (300 to 500 mg/day; n = 45) and diltiazem (180 to 300 mg/day; n = 42) on QT and QTc interval duration were analyzed in a randomized double-blind study in patients with angina pectoris. Electrocardiograms were recorded before and 14, 28, 70 and 112 days after treatment was begun. After 14 days, bepridil prolonged QT interval by 26 +/- 35 ms (range, -60 to 120 ms) and QTc (Bazett's formula) by 17 +/- 33 ms (range, -73 to 107 ms) compared to baseline (both p less than 0.05). QT or QTc did not significantly increase thereafter. However, among the 30 patients who had less than 40 ms QTc prolongation at day 14 compared with baseline, 13 (43%) exceeded this limit on at least 1 of the following visits. Diltiazem did not significantly alter QT or QTc intervals. The absolute change in QTc interval from baseline observed after 14 days of bepridil therapy was inversely proportional to the baseline QTc interval (r = -0.68; n = 42; p less than 0.001). The degree of bepridil-induced QTc prolongation on day 14 correlated with pretreatment RR interval (r = 0.36; n = 42; p less than 0.02). In conclusion, chronic administration of bepridil but not of diltiazem prolongs ventricular repolarization in patients with angina pectoris. The overall effects of bepridil therapy on QT and QTc intervals can be assessed by an electrocardiogram recorded after 14 days of treatment but subsequent measurements may be required in individual patients. A short baseline QTc interval and a slow initial heart rate may be potentially useful predictors of a greater QTc prolongation with bepridil.