123rc/medical_text huggingface dataset:
Comparison of direct and indirect measures of systemic arterial pressure during weightlifting in coronary artery disease. Based on auscultation measurements after exercise, circuit weight training in cardiac patients has been reported to provoke minimal increases in systolic pressure. Direct (brachial artery catheter) and indirect (sphygmomanometry) measures of blood pressure were compared at rest, during lifting with the legs (approximately the fourth, ninth and fourteenth repetition) and during 2 minutes of recovery after lifting with the arms and legs. Subjects performed 15 repetitions of single-arm curl, single-arm military press and single- and double-leg press exercises at 40 and 60% of the maximum load that could be lifted once on a multistation weightlifting apparatus. Indirect measures of systolic pressure at rest were 13% less than those recorded directly (130 +/- 7 vs 149 +/- 8 torr; p less than 0.01); diastolic pressures were similar using either method. This pattern was maintained during lifting with the legs at both intensities, and after exercise with both the legs and the arms. The mean systolic pressure recorded indirectly immediately after exercise was 63 torr (31%) and 76 torr (34%) less than the average peak intraarterial value recorded during leg and arm exercises, respectively. The highest intraarterial pressures were generated during the final repetitions of the set; immediately after the last repetition, both systolic and diastolic pressures rapidly decreased. It is concluded that indirect estimates of systolic pressure are significantly less than true arterial values at rest, and during and after lifting. Moreover, indirect measurements after lifting do not allow accurate conclusions to be drawn about the arterial pressures generated during lifting because of the rapid decrease in pressure that occurs after exercise.
Dyspareunia. Tracing the cause. Difficult or painful sexual intercourse is a sensitive topic for most women. The causes range from inflammation of the vulva and interstitial cystitis to marital discord. To exclude an organic disorder, a detailed pelvic examination with good lighting and magnification is in order. Dr DeWitt describes the technique for meticulous examination and discusses the diagnoses that need to be considered.
Early assessment of coronary artery bypass graft patency by high-dose dipyridamole echocardiography. To assess the role of high-dose (up to 0.84 mg/kg during 10 minutes) dipyridamole echocardiographic testing in the evaluation of coronary artery bypass graft patency early after surgery, 18 consecutive patients with angina underwent dipyridamole echocardiography and coronary angiography before and 7 to 10 days after bypass surgery. Coronary angiography showed 2- or 3-vessel disease in 7 and 11 patients, respectively. A total of 53 bypass grafts were performed. Before bypass surgery 14 patients had a positive and 4 a negative test result. No complication occurred during the test performed early after surgery. Of the 14 patients with positive dipyridamole echocardiographic results before surgery, 10 had negative and 4 had positive results after surgery. All 4 patients had negative results before and after surgery. In the 4 patients with positive results after dipyridamole echocardiographic testing before and after bypass surgery, dipyridamole time increased from 5.8 +/- 5 to 9.3 +/- 0.9 minutes (p = 0.3) after the procedure and wall motion score index at peak dipyridamole changed from 1.55 +/- 0.2 to 1.28 +/- 0.3 (p = 0.05). Forty-nine of 53 grafts were patent as seen on angiography. Dipyridamole echocardiographic results were positive in 4 of 5 patients who had at least 1 obstructed graft or native vessel obstructed distal to bypass graft insertion. The remaining patient had diagnostic electrocardiographic changes during dipyridamole infusion without wall motion abnormalities. Dipyridamole echocardiographic results were negative in all 13 patients who had complete revascularization. In the 4 patients with positive test results, the procedure correctly identified the localization of the diseased bypass graft.
Direct visualization of ruptured chordae tendineae by transesophageal two-dimensional echocardiography. To determine the value of transesophageal echocardiography in the detection of ruptured chordae tendineae, 28 patients who had surgical therapy for pure mitral regurgitation were evaluated prospectively by conventional transthoracic and transesophageal two-dimensional echocardiography. Seventeen patients (Group I) had ruptured chordae tendineae and 11 (Group II) had intact chordae tendineae. Transthoracic echocardiography detected ruptured chordae tendineae in 6 patients from Group I (sensitivity 35%) and flail leaflets in 11 patients from Group I (sensitivity 65%). Transesophageal echocardiography disclosed ruptured chordae tendineae in all 17 Group I patients (sensitivity 100%); the sensitivity was significantly higher than that of transthoracic echocardiography. No abnormal chordal echoes were visualized in any patient from Group II by either transthoracic or transesophageal echocardiography (specificity 100%). Transesophageal echocardiography is a highly sensitive method for detecting ruptured chordae tendineae and is superior to transthoracic echocardiography in establishing its diagnosis.
mtDNA depletion with variable tissue expression: a novel genetic abnormality in mitochondrial diseases. We studied two related infants with a fatal mitochondrial disease, affecting muscle in one and liver in the other. Quantitative analysis revealed a severe depletion of mtDNA in affected tissues. This genetic abnormality was also observed in muscle of an unrelated infant with myopathy and in muscle and kidney of a fourth child with myopathy and nephropathy. Biochemistry, immunohistochemistry, and in situ hybridization showed that the depletion of mtDNA in muscle fibers was correlated with a respiratory chain defect and with lack of mitochondrially translated proteins. Although the differential tissue involvement in these infants suggests mtDNA heteroplasmy, sequence analysis of mtDNA replication origins did not reveal any abnormality that could account for the low copy number.
Coronary atherosclerosis is associated with left ventricular dysfunction and dilatation in aortic stenosis. Patients with aortic stenosis develop widely variable patterns of left ventricular hypertrophy and dysfunction. We postulated that coronary atherosclerosis (CAD) may be associated with impaired left ventricular function and chamber dilatation in patients with aortic stenosis. Left ventricular mass and volumes were quantified from two-dimensional echocardiography and correlated with coronary angiography in 78 patients with severe aortic stenosis and no previous myocardial infarction or regional wall motion abnormalities. Eighteen patients (group 1) had smooth coronary arteries, 25 patients had irregular coronary arteries with 50% or less stenosis (group 2), and 35 patients had obstructive CAD (group 3). Even though the calculated valve area was similar in all three study groups, group 1 patients had higher values for ejection fraction (65 +/- 9%, 51 +/- 17%, and 48 +/- 13%; p = 0.0002), systolic mass-to-volume ratio (9.2 +/- 3.9, 5.6 +/- 2.8, and 5.2 +/- 2.2; p = 0.0001), and cardiac index (2.9 +/- 0.7, 2.5 +/- 0.7, and 2.3 +/- 0.6 l/min.min2; p = 0.015) than patients in groups 2 and 3, respectively (mean +/- SD). Mean circumferential wall stress was inversely related to severity of CAD. Multivariate analysis showed that CAD is an independent predictor of ejection fraction and mass-to-volume ratio in this group of patients. Thus, in an elderly population with severe aortic stenosis, patients with both obstructive and nonobstructive CAD have an increased incidence of left ventricular enlargement and systolic dysfunction.
Treatment of scaphoid nonunion by radical curettage, trapezoidal iliac crest bone graft, and internal fixation with a Herbert screw. Ten adult male patients with scaphoid nonunions were treated by radical curettage, trapezoidal iliac crest bone grafting, and internal fixation with a Herbert screw. The mean patient age was 24.7 years, and the mean duration of the nonunion before surgery was 37.3 months. Mean follow-up time was 30.4 months. Nine of the ten nonunions healed, although one patient required a second bone-grafting procedure. The mean postoperative grip strength was 45.0 kg, and the mean postoperative pinch strength was 11.5 kg. The mean postoperative range of motion was volar flexion, 76.1 degrees; dorsiflexion, 74.2 degrees; radial deviation, 22.1 degrees; and ulnar deviation, 40.1 degrees. The scapholunate angle decreased from a mean of 72.8 degrees preoperatively to 60.6 degrees postoperatively (p less than 0.025). The mean carpal index was 0.57 postoperatively. Mean scaphoid length increased postoperatively and was within 0.2 mm of the opposite (normal) scaphoid in every patient except the single patient with a persistent nonunion (p less than 0.025). All patients returned to work (eight as laborers), and nine of ten wrists were subjectively rated as good or excellent. The results of the series suggests that treatment of displaced scaphoid nonunion by radical curettage, trapezoidal iliac crest bone grafting, and internal fixation with a Herbert screw is an effective method of treatment that reconstitutes scaphoid anatomy and promotes excellent wrist function.
Swallowing disorders in patients with prolonged orotracheal intubation or tracheostomy tubes. Eleven patients were tested for swallowing dysfunction after prolonged orotracheal intubation. Ten had a tracheostomy tube. Mean duration of orotracheal intubation was 19.9 days, mean age 65 yr, and no patient had a concomitant neurologic deficit. All patients had a modified barium swallow with videofluoroscopy. All patients had at least one defect of 11 defects characterized. There was a mean of six defects/patient. The most common defects were delayed triggering of the swallow response (present in all patients) and pharyngeal pooling of contrast material (n = 9). Follow-up videofluoroscopy was performed in five patients (all had improved) with mean defects decreasing from 6.1 to 2.8/patient. With one exception, no patient had any defect that was worse than mild in severity. We concluded that prolonged orotracheal intubation with or without tracheostomy may cause prolonged and severe swallowing dysfunction. The deficits improve with time. The presence of a gag reflex does not confer protection against aspiration of pharyngeal contrast.
Brain pH in head injury: an image-guided 31P magnetic resonance spectroscopy study. It has been suggested that brain acidosis may follow head trauma, and therapies aimed at correcting acidosis have been proposed. Direct measurements of intracellular pH, however, have thus far not been possible in clinical situations. We have studied the intracellular brain pH in 22 patients after head injury (mean Glasgow Coma Score 6.1). Patients were investigated by a combined approach of phosphorus 31 magnetic resonance spectroscopy and magnetic resonance imaging (overall examination time 50-75 min) at a mean time of 11 days after injury (36 hours to 24 days). 31P spectra were obtained in 11 patients on assisted ventilation and in 11 patients on spontaneous ventilation. These spectra were analyzed to yield the pH in the regions studied in all the patients. All pH values were in the normal or alkalotic range when compared with 6 age-matched normal controls. No differences were found between patients on assisted ventilation and patients on spontaneous ventilation. When analyzed as a group, the brain pH in the focal lesions appeared to increase in the first days, to reach a peak in the alkalotic range in the second week, and to return toward normal within 3 weeks from acute injury. Our results suggest that there is no evidence of posttraumatic intracellular brain acidosis in recent human head injury, and therefore, therapies aimed at alkalinizing brain cells need to be reconsidered.
Small cell carcinomas of the large intestine. The authors studied the clinical and pathologic features of 38 small cell carcinomas of the large intestine. Most were located in the right colon. Overlying adenomas were present in 45% and squamous differentiation in 21% of tumors. Endocrine differentiation was present in all tumors by at least one method; neuron-specific enolase, dense-core granules, and synaptophysin were present in most cases. Seventy-one percent of tumors metastasized to the liver; 64% of patients were dead at five months follow-up. Twenty-one poorly differentiated adenocarcinomas and undifferentiated carcinomas of the large intestine accessioned during the same period showed less endocrine (7 of 21) and squamous differentiation (1 of 15) and fewer liver metastases (4 of 15) than did small cell carcinomas. Among all 59 tumors studied, small cell histologic characteristics correlated better with liver involvement than did endocrine markers or other histologic features. Small cell carcinomas of the large intestine are aggressive tumors with a propensity for early liver involvement. Although there is a spectrum of squamous, endocrine, and glandular features in large bowel tumors of low degrees of differentiation, the identification of a small cell component appears to be most clinically relevant.
Rigid spine syndrome with respiratory failure. The pathogenesis and therapy of respiratory failure in the rigid spine syndrome are discussed in two cases who improved with respiratory assistance. In both cases, the partial pressures of oxygen and carbon dioxide were reversed in arterial blood gas analysis and %VC was less than 30%. Remission from respiratory failure has been obtained by the use of a ventilator during the night. The cause of the respiratory failure in both cases was severe restrictive respiratory dysfunction due to extreme flattening of the chest and fixation of the thorax during respiration as a result of contracture of costovertebral joints. All the previously reported cases of the rigid spine syndrome with respiratory failure died. Appropriate use of the ventilator can improve the prognosis.
Thickness of carotid artery atherosclerotic plaque and ischemic risk. Noninvasive duplex scanning of carotid artery atherosclerotic plaque was performed in 286 consecutive patients referred to a cerebrovascular diagnostic laboratory. The presence and thickness of such plaque in the region of the carotid bifurcation were examined for association with the degree of vessel stenosis, age, sex, smoking history, history of prior transient ischemic attack or stroke, and systemic manifestations of atherosclerotic disease. Atherosclerotic plaque thickness was positively correlated with degree of vessel stenosis (P less than 0.0001). Both parameters were independent predictors of cerebrovascular events but plaque thickness was a better predictor of prior transient ischemic attacks (P less than 0.05), and vessel stenosis was a better predictor of prior stroke (P less than 0.005). Patient age (P less than 0.001) and pack-years of cigarette use (P less than 0.001) were independent positive predictors of carotid atherosclerotic plaque thickness. The greatest effect of smoking and atherosclerotic plaque thickness was seen in heavy smokers younger than age 55. Both carotid artery plaque thickness and pack-years of smoking were significant independent predictors of other systemic manifestations of atherosclerotic disease (P less than 0.05). Such noninvasive scanning of carotid artery atherosclerotic plaque demonstrates the significant role of age and smoking in the progression of disease. It also suggests a significant role for carotid atherosclerotic artery plaque in the pathophysiology of cerebrovascular events, especially transient ischemic attacks, even prior to the production of a flow-limiting stenosis. Finally, noninvasive screening of carotid artery plaque may provide a useful marker for the patient at risk for systemic atherosclerotic disease and identify the patient for whom maximal atherosclerotic risk factor modification is needed.
Laryngeal myxoma. Myxoma is a rare mesenchymal tumor that is especially uncommon in the head and neck. We report a case of a myxoma of the larynx in a 70-year-old man, which, to our knowledge, is the second case reported in the English-language literature. Although benign, myxomas have a propensity for local recurrence due to their tendency to infiltrate surrounding tissues. They commonly appear encapsulated, but simple enucleation is not adequate treatment; excision should include a margin of normal tissue around the tumor.
Cognitive strategies during coincident timing tasks. Research findings suggest that experience and cognitive strategies contribute to successful performance during perceptual-motor tasks. This article critically reviews selected literature on the effects of information-processing skills, preferred movement time, experience, and task difficulty on performance during coincident timing tasks. Theoretical information and research findings are discussed, and their applications to clinical practice are considered. Clinical recommendations include assessment of coincident timing skills and use of functional activities that provide opportunities to explore and dynamically interact with the environment.
Effect of Bay U 3405, a new thromboxane antagonist, on collagen-induced thromboembolism in rabbits. Bay U 3405 [(3R)-3-(4-fluorophenylsulfonamido)-1,2,3,4-tetrahydro-9- carbazolepropanoic acid] potently inhibits platelet aggregation, thromboxane A2-induced contraction of smooth muscles, and coronary artery thrombosis. We have previously demonstrated inhibition of arachidonic acid-induced sudden death by Bay U 3405. The purpose of this study was to investigate the effects of Bay U 3405 on thromboembolism provoked by collagen. Collagen fibrils dissolved in an isotonic glucose solution were injected into a marginal ear vein of anesthetized rabbits. Sudden death occurred within a few minutes due to elevated thromboxane A2 levels causing intravascular platelet aggregation and myocardial ischemia. In the vehicle-treated group, 100% of the animals died. One of the most prominent parameters was the massive fall in blood pressure. All animals pretreated with 10 mg/kg orally Bay U 3405 survived, showing only a transient hypotensive effect. Tracings of the electrocardiogram and heart rate were unchanged. Bay U 3405 will therefore be useful to elucidate the role of thromboxane A2 in various cardiovascular and respiratory diseases.
The daylong pattern of the antianginal effect of long-term three times daily administered isosorbide dinitrate Three times daily administration of isosorbide dinitrate may avoid much of the tolerance seen with more frequent dosing. To determine the daylong pattern of the antianginal effect of three times daily isosorbide dinitrate, eight men with stable exertional angina and a positive exercise test were studied. The subjects had demonstrated increased exercise duration in response to oral isosorbide dinitrate therapy and absence of complete tolerance to long-term three times daily isosorbide dinitrate. Treadmill exercise to onset of angina was performed over 2 days at 8 AM, 9 AM, 11 AM, 1 PM, 2 PM, 4 PM, 6 PM and 7 PM. On one day each patient received isosorbide dinitrate at 8 AM, 1 PM and 6 PM in a previously titrated dose (mean 27.5 mg), which had been taken three times daily for at least 2 weeks. On the other day at the same hours each patient received double blind a placebo identical in appearance to isosorbide dinitrate. One hour after the 8 AM dose of isosorbide dinitrate, mean systolic blood pressure at rest had fallen by 19 mm Hg and mean exercise time to angina increased by 200 s. However, by 11 AM exercise time had returned to control level. One hour after the 1 PM dose of isosorbide dinitrate, exercise time increased by a mean of 150 s but was again at control level 2 h later.
Melanoma in pregnancy. The clinical course of malignant melanoma in pregnancy has been a subject of controversy, but current evidence indicates that it is similar to the clinical course in non-pregnant patients. Early detection and biopsy of localized disease is crucial because early treatment provides an excellent prognosis. Surgical excision is the primary therapy for this disease. As the primary care provider for many women in the reproductive age group, obstetrician-gynecologists have an opportunity to detect these lesions at their earliest stages when they are amenable to cure. Overall, maternal metastases to the fetus and placenta are very rare events and do not warrant elective termination based on the maternal diagnosis. However, a thorough examination of the infant and placenta should be done in all cases of melanoma complicating pregnancy. After treatment, long-term follow-up is recommended. Since most recurrences develop within 3 years after the diagnosis, it remains prudent to recommend that these patients avoid a subsequent pregnancy during this interval.
Overt hepatic encephalopathy precipitated by zinc deficiency. Encephalopathy in liver disease may be unresponsive to protein restriction, lactulose, and neomycin. Zinc supplements have been reported to improve psychometric performance in liver cirrhosis, but the importance of zinc deficiency in overt hepatic encephalopathy has not yet been clearly established. A patient with severe recurrent hepatic encephalopathy was studied to determine the relation between her signs of encephalopathy and zinc deficiency. The study included a period in which zinc deficiency was artificially induced by oral histidine. An episode of overt encephalopathy occurred that was identical to earlier episodes and responded to oral zinc. The study showed an association between encephalopathy and zinc deficiency by successive zinc depletion and supplementation regimens. Long-term zinc supplementation improved severe recurrent hepatic encephalopathy and therefore the quality of life.
Effect of lovastatin on intimal hyperplasia after balloon angioplasty: a study in an atherosclerotic hypercholesterolemic rabbit. Restenosis, the major limitation of balloon angioplasty, is the result of intimal hyperplasia after the procedure. Lovastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) inhibitor, may influence intimal hyperplasia by lowering serum cholesterol and by blocking deoxyribonucleic acid (DNA) synthesis. To determine whether lovastatin reduces intimal hyperplasia, a prospective, randomized blinded study was performed in 60 atherosclerotic New Zealand White male rabbits. Atherosclerosis was produced by air desiccation injury followed by a 28 day diet of 2% cholesterol and 6% peanut oil that was terminated before balloon angioplasty was performed. Angioplasty could not be performed in 14 rabbits with bilateral femoral artery occlusion, and in one rabbit the procedure was a technical failure. Forty-five rabbits underwent balloon angioplasty performed with use of a 2.5-mm balloon inflated to 10 atm for three 1 min dilations at 1 min intervals. Seven rabbits died during the procedure. Thirty-eight rabbits were randomized to either a lovastatin group (6 mg/kg body weight per day) or a control group. Angioplasty was performed on all patent vessels (n = 54); the procedure was bilateral in 16 rabbits and unilateral in 22. Fifteen lovastatin-treated and 15 control rabbits survived 39 days after angioplasty and were then killed. Angiograms, obtained before and 10 min and 39 days after balloon angioplasty, were read with use of electronic calipers by two observers who had no knowledge of treatment data. After the rabbits were killed, vessels were pressure perfused using a standardized protocol to maintain in vivo dimensions for blinded quantitative histologic analysis.