123rc/medical_text huggingface dataset:
Prostaglandin modulation of early afterdepolarizations and ventricular tachyarrhythmias induced by cesium chloride combined with efferent cardiac sympathetic stimulation in dogs. Prostaglandins inhibit efferent cardiac sympathetic nerve effects by acting at presynaptic sites and may act to suppress some arrhythmias. In the present study, the effects of intravenous administration of prostacyclin (PGI2) and prostaglandin E2 (PGE2) on early afterdepolarizations and ventricular tachycardia induced by cesium chloride (0.5 mmol/liter per kg body weight intravenously) combined with stimulation of bilateral ansae subclaviae in anesthetized dogs were examined. The right atrium was paced at a constant cycle length of 600 ms. A left ventricular endocardial monophasic action potential catheter was used to detect early afterdepolarizations. Prostacyclin (0.2 microgram/kg per min) reduced the amplitude of the early afterdepolarizations (39.2 +/- 8.4% of the monophasic action potential amplitude during control study to 28.7 +/- 5.5%, n = 10; p less than 0.001) as well as the prevalence of ventricular tachycardia (11 of 14 dogs during control study to 5 of 14 dogs; p = 0.031). Prostaglandin E2 (0.2 to 0.6 microgram/kg per min) did not significantly reduce the early afterdepolarization amplitude (34.7 +/- 8.9% to 25.1 +/- 10.7%, n = 8; p = 0.085) or the prevalence of ventricular tachycardia (8 of 10 versus 6 of 10 dogs; p = 0.50). Alpha- and beta-adrenoceptor blockade with combined intravenous administration of propranolol (0.5 mg/kg) and phentolamine (0.3 mg/kg) decreased the amplitude of the early afterdepolarizations induced by cesium chloride and bilateral ansae subclaviae stimulation from 38.6 +/- 11.2% to 18.8 +/- 3.3% (n = 6; p = 0.005). Additional administration of PGI2 further reduced the early afterdepolarization amplitude from 18.8 +/- 3.3% to 9.8 +/- 4.8% (n = 6; p = 0.001).
Beta blockers and the primary prevention of nonfatal myocardial infarction in patients with high blood pressure. A population-based, case-control study was conducted to determine whether beta blockers, used for the treatment of high blood pressure, prevent first events of coronary heart disease. All study subjects were health-maintenance organization enrollees with pharmacologically treated hypertension. Patients presented in 1982 to 1984 with new coronary heart disease, and control subjects were a probability sample of eligible hypertensive enrollees free of coronary heart disease. With the investigators blind to case-control status, the subjects' medical records were reviewed for other coronary risk factors, and the health-maintenance organization's computerized pharmacy database was used to ascertain the use of beta blockers. A larger proportion of controls than cases were using beta blockers. This difference was confined to the subgroup with nonfatal myocardial infarctions. For current use, the estimated relative risk for nonfatal myocardial infarction was 0.62 (95% confidence interval, 0.39 to 0.99). Among current users of beta blockers, higher doses conferred greater protection. Past use and total lifetime intake of beta blockers were only weakly associated with case-control status. The current use of beta blockers may prevent first events of nonfatal myocardial infarction in patients with high blood pressure.
Recent changes in the treatment of aortoiliac occlusive disease by the Oxford Regional Vascular Service. Over the four years from 1 January 1985 to 31 December 1988, 192 patients were treated for aortoiliac occlusive disease by the Oxford Regional Vascular Service. The number of patients treated by percutaneous transluminal angioplasty increased from two in the first year of the study to 34 in the third year of the study. This increase was accompanied by a decrease in the proportion of patients treated by aortobifemoral bypass but the proportion of patients treated by extra-anatomic bypass remained constant at around 30 per cent. Twice as many patients were treated in the fourth year as in the first year of the study so that the number of surgical operations increased despite many patients being treated exclusively by percutaneous transluminal angioplasty. The number of patients requiring mandatory treatment for limb salvage increased by 109 per cent and optional treatment for intermittent claudication by 85 per cent. The introduction of percutaneous transluminal angioplasty in Oxford has coincided with an increase in the number of patients presenting with symptomatic aortoiliac occlusive disease and has allowed twice as many people to be treated while the number of aortobifemoral bypass operations has remained unchanged. It is concluded that the introduction of percutaneous transluminal angioplasty has not only generated its own workload but has also led to an increased demand for surgical reconstruction for aortoiliac occlusive disease.
Thoracoplasty: current application to the infected pleural space Thoracoplasty, once commonly used in the management of cavitary pulmonary disease, continues to find application in the obliteration of infected pleural spaces. This study reports a series of 13 patients receiving thoracoplasty between 1976 and 1989. Five patients had chronic apical empyema spaces without prior resection of lung tissue. Two of the empyemas were due to tuberculosis, two were due to atypical mycobacteria, and one was due to postpneumonic empyema. All patients had extensive destruction of upper lobe tissue. Eight patients had undergone prior pulmonary resection; 3 had persistent infected spaces in the early postoperative period, 3 had development of empyemas and bronchopleural fistulas late (5 to 19 years) after pulmonary resection, and 2 had postpneumonectomy empyema. All patients had rigid cavity walls preventing space obliteration by rib removal alone and required concomitant resection of the thickened pleura and intercostal muscle tissues. Bronchopleural fistulas were present in 11 patients and were closed with adjacent nonintercostal muscle. All patients survived and had successful obliteration of the infected spaces with acceptable physiological and cosmetic results. We conclude that thoracoplasty remains a useful procedure in the management of the infected pleural space in select patients.
A prognostic system for transient ischemia or minor stroke. OBJECTIVE: To build a prognostic system for patients with carotid transient ischemic attack or minor stroke. DESIGN: Inception cohort study with 2-year follow-up. SETTING: Urban community teaching hospital. PATIENTS: Eligible patients (n = 142), identified on a carotid ultrasound roster, had been hospitalized between 1984 and 1987 within 30 days of a first carotid transient ischemic attack or minor stroke. MEASUREMENTS: Stroke or death within 2 years. MAIN RESULTS: Three factors were associated with stroke or death: age of more than 65 years, diabetes, and hypertension. Based on regression coefficients, age of more than 65 years was assigned 3 points; diabetes, 3 points; and hypertension, 2 points. An initial prognostic system comprised risk groups 1 (0 points), 2 (1 to 5 points), and 3 (6 to 8 points). Outcome rates in the three groups were 2%, 31%, and 54% (P less than 0.0001), respectively. In an independent test sample, the corresponding outcome rates for the initial system were 12%, 21%, and 31% (P = 0.04). A final prognostic system, including two additional predictors (coronary heart disease [1 point] and the distinction between stroke and transient ischemic attack for the baseline event [2 points]), comprised risk groups 1 (0 to 2 points), 2 (3 to 6 points), and 3 (7 to 11 points). Corresponding outcome rates were 3%, 27%, and 48% (P less than 0.001) in the original cohort and 10%, 21%, and 59% (P less than 0.001) in the test cohort. CONCLUSION: For selected patients with carotid transient ischemia or minor stroke, five clinical features can be combined to stratify effectively the risk for a subsequent stroke or death.
The renally compromised older hypertensive: therapeutic considerations. Although the slow progression of renal insufficiency caused by aging does not usually reach the clinical disease level, nephron loss may be accelerated by the concomitant presence of hypertension and renal artery atherosclerosis. Treatment of hypertension and correction of other risk factors promoting atherosclerosis is appropriate in the elderly. Consideration should be given to a search for reversible causes of renal functional deterioration in elderly patients, particularly in those with increasingly refractory hypertension. In the uncomplicated elderly hypertensive, renal function appears to be adequately preserved if blood pressure is well controlled, although there may be a subset in whom factors other than blood pressure itself, such as glomerular hemodynamic disturbances, promote progressive renal dysfunction.
Immunohistochemical demonstration of the placental form of glutathione S-transferase, a detoxifying enzyme in human gliomas. Expression of the human placental form of glutathion S-transferase (GST-pi) in human gliomas was investigated by immunohistochemical methods, and the result was compared with that of normal human glial cells. The gliomas in this study were composed of five benign astrocytomas (Grade 2), ten anaplastic astrocytomas (Grade 3), and 16 glioblastomas (Grade 4). Normal human glial cells showed only a weak immunostaining response for GST-pi in the cytoplasm or some nuclear membranes. All of benign astrocytomas had diffusely weak GST-pi immunostaining, resembling that of normal glial cells. With increasing grade, gliomas showed a strongly positive reaction for GST-pi. The positive reactions were remarkable especially in the gemistocytes and giant cells in the high-grade gliomas. These results suggest that cells of gliomas have some detoxifying function and the expression of this detoxifying enzyme, GST-pi, is related to the degree of malignancy of the gliomas.
Long-term echocardiographic follow-up of patients with a tricuspid bioprosthesis. To clarify the long-term results of bioprosthetic valve function in the tricuspid position, 29 consecutive patients who underwent tricuspid valve replacement (TVR) were evaluated. There were 20 girls/women and 9 boys/men, with ages ranging from 6 to 61 years (mean 41.4 years). The bioprosthetic valves included Hancock in 2, and Carpentier-Edwards in 27. The follow-up period ranged from 32 to 145 months (mean 89 months). Regurgitant flow of the tricuspid bioprosthesis was studied by color Doppler echocardiography. Peak velocity (Vp) and pressure half time (PHT) were measured by continuous wave Doppler echocardiography. Operative mortality was 13.7% (4/29), with the actuarial survival rate, including operative deaths, 75% at 10 years. Valve thrombosis developed in one patient 4 years after TVR. Color Doppler showed regurgitation in 7 of the 20 patients who were completely followed up, but they were all asymptomatic and required no special intervention. Cusp tear or calcification requiring reoperation was not observed in this study, including 8 patients younger than 35 years of age. The Vp was significantly slower, and PHT was significantly prolonged, in the tricuspid rather than the mitral position. These data demonstrate that bioprosthetic valves in the tricuspid position can be used safely. Doppler examination should be performed taking these different flow dynamics into account.
Central neurogenic hyperventilation in invasive laryngeal carcinoma. We describe a patient with central neurogenic hyperventilation secondary to extension of a laryngeal tumor into the base of the brain, resulting in extrinsic compression of the medulla. Such an association has not been previously described. Unique features which distinguish this patient from previously reported cases are emphasized. Possible mechanisms involved in pathogenesis, as well as types of therapy, are outlined.
Cerebellar and frontal hypometabolism in alcoholic cerebellar degeneration studied with positron emission tomography. Local cerebral metabolic rate for glucose was studied utilizing 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography (PET) in 14 chronically alcohol-dependent patients and 8 normal control subjects of similar age and sex. Nine of the 14 patients (Group A) had clinical signs of alcoholic cerebellar degeneration, and the remaining 5 (Group B) did not have signs of alcoholic cerebellar degeneration. PET studies of Group A revealed significantly decreased local cerebral metabolic rates for glucose in the superior cerebellar vermis in comparison with the normal control subjects. Group B did not show decreased rates in the cerebellum. Both Groups A and B showed decreased local cerebral metabolic rates for glucose bilaterally in the medial frontal area of the cerebral cortex in comparison with the normal control subjects. The severity of the clinical neurological impairment was significantly correlated with the degree of hypometabolism in both the superior cerebellar vermis and the medial frontal region of the cerebral cortex. The degree of atrophy detected in computed tomography scans was significantly correlated with local cerebral metabolic rates in the medial frontal area of the cerebral cortex, but not in the cerebellum. The data indicate that hypometabolism in the superior cerebellar vermis closely follows clinical symptomatology in patients with alcoholic cerebellar degeneration, and does not occur in alcohol-dependent patients without clinical evidence of cerebellar dysfunction. Hypometabolism in the medial frontal region of the cerebral cortex is a prominent finding in alcohol-dependent patients with or without alcoholic cerebellar degeneration.
Elevated soluble interleukin-2 receptor levels in patients with active multiple sclerosis. The level of soluble interleukin-2 receptor (sIL-2R) was quantitated with enzyme-linked immunosorbent assay in serum and cerebrospinal fluid obtained from 24 patients with multiple sclerosis and 10 patients with other neurological disorders in whom immunological mechanisms are unlikely to participate. The sIL-2R level in the serum and cerebrospinal fluid of patients with multiple sclerosis in relapse was significantly higher compared with patients with multiple sclerosis in remission and with controls. The sIL-2R level, especially in the cerebrospinal fluid, showed higher sensitivity and specificity than other clinical parameters including the cerebrospinal fluid IgG ratio, peripheral lymphocyte CD4/CD8 ratio, cerebrospinal fluid myelin basic protein and oligoclonal bands. Our data suggest that measurement of the sIL-2R level may be useful in evaluating disease activity in patients with multiple sclerosis.
Radiation therapy for intraductal carcinoma. Is it an equal alternative? Of 213 consecutive patients with intraductal carcinoma, 109 were selectively treated with mastectomy and 104 with radiation therapy. There were eight local recurrences, seven in patients treated with radiation therapy and one in a patient treated with mastectomy. Histologically, there were 110 comedocarcinomas and 103 noncomedocarcinomas. Seven local recurrences occurred in patients with comedocarcinomas and one in a patient with a noncomedo tumor. Three (38%) of eight local recurrences (all comedo) were invasive. The 5-year actuarial survival for all subgroups was 100%. The median follow-up was 51 months. Intraductal carcinoma is unlikely to metastasize to axillary lymph nodes, and routine dissection is unnecessary. Ductal carcinoma in situ of the comedo variety is more aggressive and more likely to recur than its noncomedo counterpart. We currently view conservative therapy for patients with intraductal comedocarcinoma with caution.
Intramedullary spinal ependymal cyst: case report. A cervical intramedullary spinal ependymal cyst in a 39-year-old man is reported. Diagnosis was made through magnetic resonance imaging. Total enucleation was possible. This is the sixth such reported case.
The progression of mild idiopathic dementia in a community population. Thirty-one subjects aged 75 years and over who were identified as suffering from mild, idiopathic dementia in a large community survey were reviewed at annual intervals for 2 years. Diagnoses and severity ratings were based on defined criteria following a mental state examination, a medical and psychiatric history, detailed cognitive testing, and an interview with relatives or other key informants. Fourteen subjects became more severely demented within 2 years. The initial cognitive test battery failed to reveal any differences between respondents whose dementia advanced and those whose condition remained unchanged, but, in the former group, subjects' symptoms had been present for longer, and a greater proportion had been recognised as demented, or possibly demented, by their general practitioners. We suggest that subjects whose dementia progressed had actually been more severely disabled at the time of identification.
Effects of mental exercise in patients with dilated cardiomyopathy and congestive heart failure. An echocardiographic Doppler study. To assess the effects of mental stress on left ventricular diastolic function in patients with congestive heart failure, nine patients aged 57 +/- 12 years with dilated cardiomyopathy (end-diastolic volume, more than 110 ml/m2; ejection fraction, less than 40%; mean, 28 +/- 8%) and congestive heart failure in New York Heart Association functional class II or III and 14 normal volunteers (mean age, 49 +/- 8 years) were studied during mental arithmetic lasting 10 minutes with echocardiographic Doppler monitoring of transmitral flow velocity. During mental arithmetic, the ratio of peak flow velocity in early versus late diastole (E/A) and deceleration time of early diastole did not change in normal controls. However, E/A increased significantly (from 1.6 +/- 1.5 to 1.9 +/- 1.7; p less than 0.01) and deceleration time markedly decreased (from 156 +/- 49 to 108 +/- 31 msec; p less than 0.001) in patients with congestive heart failure. In 16 postinfarct patients with ejection fraction of less than 40% studied during mental arithmetic with simultaneous hemodynamics and Doppler recordings, good correlations were found between pulmonary wedge pressure and Doppler parameters (wedge pressure versus E/A, r = 0.89; wedge pressure versus deceleration time, r = -0.87). During mental arithmetic, the pulmonary wedge pressure-E/A correlation was weaker (r = 0.67), whereas the correlation between pulmonary wedge pressure and deceleration time was stronger (r = 0.91). The value of 153 msec in deceleration time was the best cutoff point in predicting 12 mm Hg pulmonary wedge pressure, both at rest and during mental arithmetic: the higher the deceleration time, the lower the pulmonary wedge pressure, and vice versa. Among patients with congestive heart failure, five showed normal baseline deceleration time (195 +/- 21 msec; pattern 1), and the remaining four showed a short (less than 153 msec) deceleration time (108 +/- 13 msec; pattern 2). During mental arithmetic, deceleration time markedly decreased to as short as 119 +/- 20 msec in all patients except one with baseline pattern 1. Deceleration time further decreased to 75 +/- 6 msec in all patients with baseline pattern 2. Mental arithmetic induces changes in left ventricular diastolic function in patients with congestive heart failure. Transmitral echocardiographic Doppler provides a simple noninvasive method of estimating and monitoring pulmonary wedge pressure in patients with severe left ventricular dysfunction.
Effects of the phospholipase inhibitor mepacrine on injury in ischemic and metabolically inhibited adult isolated myocytes. The phospholipase inhibitor mepacrine has been shown to delay cell death of metabolically inhibited cultured cardiomyocytes. The present study was initiated to determine if mepacrine also delays cell death and development of osmotic fragility of both metabolically inhibited and ischemic adult rat cardiomyocytes. Isolated myocyte suspensions were incubated with 3 mmol/l (millimolar) iodoacetic acid and 6 mmol/l amytal (inhibited) or were pelleted into a slurry and layered with oil (ischemic) in the presence and absence of 10 or 50 mumol/l (micromolar) mepacrine. Rates of contracture, cell viability as determined by trypan blue permeability, cell viability after osmotic swelling in 170 mOsm media (osmotic fragility), and cell morphology were monitored. Mepacrine had no effects on rates of contracture, but was found to significantly delay cell death during isotonic incubations of both metabolically inhibited and ischemic cells. In contrast, mepacrine had no effect on the development of osmotic fragility. Incubation of metabolically inhibited myocytes in calcium-free media did not delay contracture or cell injury, but did attenuate the protective effects of mepacrine. This study confirms previous reports that mepacrine protects cells from injury, extends the observations of protection to ischemic isolated adult myocytes, but shows that development of osmotic fragility is not inhibited by mepacrine.
Cerebral venography with MR. The authors describe a two-dimensional time-of-flight magnetic resonance (MR) angiography technique to create projection venograms of the head. The technique was applied to 27 healthy volunteers and 39 patients. The superior sagittal and straight sinuses, the internal cerebral veins, and the Galen vein were visualized in all the volunteers. Other veins were seen in a high percentage of subjects. Systematic comparison of digital subtraction angiography (DSA) after intraarterial contrast medium injection and MR venography in patients showed good correlation between the two techniques. MR venography proved helpful in identifying thrombosis or patency of cerebral veins and sinuses and showed collateral venous drainage and venous drainage from arteriovenous malformations. There was good correlation between conventional contrast angiography and MR venography. In conclusion, MR venography is considered reliable for showing the cerebral venous system and provides information additional to that of conventional spin-echo imaging.
The modified superior based pharyngeal flap. Part III. A retrospective study. A retrospective study of 31 patients who had diagnosed velopharyngeal incompetence and were surgically managed with the modified superior based pharyngeal flap was completed. The following were analyzed: age at time of operation, gender, physical status, diagnostic protocol, length of operation (length of total surgery) and length of superior based pharyngeal flap, length of postoperative hospital stay, length of total hospital stay, length of follow-up, speech results, complications, patient care, and medication. The result showed that the optimal timing for correction of velopharyngeal incompetence was between 3 and 6 years of age. The mean length of total hospital stay was 2.7 days, postoperative complications were minimal, and speech results were generally good.
Elevated plasma endothelin-1 concentrations are associated with the severity of illness in patients with sepsis. Plasma immunoreactive endothelin-1 concentrations were determined by radioimmunoassay in 11 septic patients during the first 24 hours after the development of the sepsis syndrome in 15 nonseptic postoperative patients studied 24 hours after open heart surgery and in 14 healthy volunteers. Mean endothelin-1 plasma concentrations were significantly (p less than 0.001) increased in septic patients (19.9 +/- 2.2 pg/mL, mean +/- standard error) compared to concentrations found in postoperative cardiac patients (11.9 +/- 0.7 pg/mL) or in healthy volunteers (6.1 +/- 0.3 pg/mL). In septic patients elevated plasma concentrations of endothelin-1 were inversely correlated with cardiac index (r = -0.80, p less than 0.005) and positively correlated the severity of illness as documented by APACHE II score (r = 0.74, p less than 0.01) and plasma creatinine levels (r = 0.80, p less than 0.005). No such correlations were found in postoperative cardiac patients. These results indicate that endothelin-1 concentrations are correlated with the severity of illness and depression of cardiac output in patients with sepsis.