123rc/medical_text huggingface dataset:
Myocardial sulfhydryl pool alterations occur during reperfusion after brief and prolonged myocardial ischemia in vivo. Myocardial sulfhydryl (SH)-containing compounds, including reduced glutathione (GSH), are both defenses against and potential markers of reactive oxygen metabolite injury during ischemia and reperfusion. We examined the alterations in GSH and other myocardial SH pools during reperfusion in anesthetized dogs exposed to brief (15 minutes, n = 7) or prolonged (90 minutes, n = 6) regional ischemia caused by occlusion of the left anterior descending artery. Ninety minutes of ischemia followed by 5 hours of reperfusion, which resulted in myocardial necrosis of 43.9 +/- 4.0% of the area at risk, caused a 22% reduction in total myocardial SH groups (p less than 0.01), a 57% decrease in nonprotein myocardial SH groups (p less than 0.01), a 56% decrease in GSH (p less than 0.01), and a 62% decrease in non-GSH, nonprotein SH groups (p less than 0.02). However, protein SH groups were not significantly reduced (12% decrease, p = NS). Also, myocardial release of GSH and oxidized glutathione (GSSG) into the coronary venous effluent occurred during early reperfusion. In contrast, 15 minutes of ischemia, followed by 30 minutes of reperfusion, did not alter myocardial total SH groups, protein SH groups, or GSH (9% decrease, p = NS); nor was there reperfusion release of GSH or GSSG. However, even with brief ischemia, nonprotein SH groups decreased 23% (p less than 0.05), due mainly to a 59% decrease in the non-GSH, nonprotein SH pool (p less than 0.05). These changes after brief ischemia occurred without alterations in myocardial GSSG or the GSH/GSSG ratio.
Magnetic resonance angiography of abdominal vessels: early experience using the three-dimensional phase-contrast technique. Based on three-dimensional acquisition of three sequences sensitive to one flow-direction, abdominal magnetic resonance phase-contrast angiography (MRA) was performed in 13 volunteers and 20 patients. The subjects received no antiperistaltic medication and were allowed to breath normally during the three acquisition periods of 11 minutes. The frequency of demonstration of the normal aorta, superior mesenteric and right and left renal arteries was 100%/100%/91%/100%, and of the inferior vena cava, splenic, superior mesenteric and portal veins was 92%/67%/92%/100%, respectively, whereas other abdominal vessels were seen less constantly. In renal artery stenosis or occlusion, MRA detected eight out of nine pathological arteries, missed only a minimal stenosis and was never false positive. In all 10 cases of portal hypertension, MRA demonstrated the venous collaterals detected by conventional angiography and in six cases showed more collaterals, particularly paravertebral vessels. A Budd-Chiari syndrome was investigated as well. If the accuracy of MRA can be proved in larger studies, it may become an important diagnostic tool in evaluating abdominal vascular pathology, such as renal artery stenosis or portal hypertension.
Preoperative selection for curable renovascular hypertension. Clinical research has defined the criteria for identifying "curable" renovascular hypertension. The prediction is based on the measurement of plasma renin activity in peripheral veins, renal veins, and the aorta. Renin profiles can be examined with the method of Laragh and coworkers (the so-called incremental method), in which values for plasma renin activity are incorporated into formulas to compute indexed parameters. A score is attributed to each index and the prediction is based on the final score. Because the identification of curable renovascular hypertension is made according to numerical rules, the method is easily transformed into a computer-assisted process. The program is written in BASIC, and it is short enough to run on a personal computer.
Survival of premenopausal women with metastatic breast cancer. Long-term follow-up of Eastern Cooperative Group and Cancer and Leukemia Group B studies. In premenopausal women with metastatic breast cancer, differences in survival curves early during follow-up can be misleading. The authors therefore analyzed long-term survival in 378 patients, entered in three randomized trials, started between 1973 and 1978. Combined data from the three trials were used to increase the power for identifying prognostic variables. Cancer and Leukemia Group B (CALGB) trial 7382 randomized patients to oophorectomy plus either cyclophosphamide or combination chemotherapy or observation. Eastern Cooperative Oncology Group (ECOG) 2174 randomized patients who had not progressed 3 months after oophorectomy to combination chemotherapy or combination chemotherapy or observation. Trial ECOG 2177 randomized estrogen receptor (ER) positive or ER-unknown patients to oophorectomy plus combination chemotherapy or immediate combination chemotherapy, and ER-negative patients were directly assigned to combination chemotherapy. Hence ER-negative patients need not have been healthy enough to be randomized to oophorectomy. With only 14% of the patients still alive, median survival on the three studies was 30, 24, and 28 months. The median survival of individual treatments changed noticeably in ECOG 2174 and ECOG 2177 with long-term follow-up. At this time there are no differences in survival between randomized regimens in any of the three trials. In a multivariate model, factors associated with significantly poorer survival were visceral-dominant disease, nodal metastases, breast metastases, age younger than 45 years, ER negativity, and not receiving chemotherapy immediately after oophorectomy. This treatment difference was thus not due to imbalances in the prognostic variables used in the model, but it may be due to imbalances of unknown prognostic factors or differences in patient selection.
Heterotopic tissue in lymph nodes. An unrecognized problem. Heterotopic tissue in lymph nodes is both unknown to clinicians and a potential source of confusion with metastatic disease. We reviewed the English literature and found 289 cases of heterotopic tissue in lymph nodes. The majority (84%) of these patients were operated on for malignant neoplasms. The most frequent sites of occurrence was the pelvis (67%), followed by the axilla (14%), neck (14%), groin (3%), abdomen (2%), and mediastinum (less than 1%). The tissue seen is site-specific and frequently resembles a neighboring organ. Three cases have been reported in which heterotopic tissue was mistaken for metastatic disease. These cases illustrate the importance of being familiar with heterotopic tissue in lymph nodes and identifying it when it does occur, to avoid inappropriate therapy.
Four-part valgus impacted fractures of the proximal humerus. There is a specific type of displaced four-part fracture of the proximal humerus which consists of valgus impaction of the head fragment; this deserves special consideration because the rate of avascular necrosis is lower than that of other displaced four-part fractures. Using either closed reduction or limited open reduction and minimal internal fixation, 74% satisfactory results can be achieved in this injury.
Dysgerminoma of the ovary: review of 27 cases. Twenty-seven patients with pure dysgerminoma were seen at the Tata Memorial Hospital, Bombay, between January 1980 and December 1984. Of the 10 patients in stage I, 2 patients underwent a unilateral salpingoophorectomy (USO) and were kept under observation without any adjuvant therapy, while the remaining patients received adjuvant treatment following surgery. All of the 6 patients in stage II and 4 of 7 in stage III had total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAHBSO) followed by postoperative radiotherapy. One patient presented in stage IV and 3 patients presented with recurrence after previous definitive treatment undertaken at other institutions. The disease free, as well as the overall survival, at 108 months, for the 24 cases primarily treated at this institution, is 81% and 88% respectively, and, for patients in stages I and II, 100% (Kaplan-Meier estimation). The need for controlled clinical trials to devise optimal therapy in the early clinical stages and use of chemotherapy for advanced stages of this highly curable entity are stressed.
Nerve growth factor prevents toxic neuropathy in mice. Taxol is a promising new antitumor drug with therapeutic use that is limited by a toxic sensory neuropathy. Taxol is also cytotoxic to dorsal root ganglion neurons in vitro, but this effect is prevented by cotreatment with the trophic protein, nerve growth factor. We sought to develop an animal model and then to determine whether nerve growth factor can prevent taxol neuropathy in vivo. Administration of taxol to mice resulted in a profound sensory neuropathy characterized by decreases in dorsal root ganglion content of the peptide neurotransmitter, substance P, elevated threshold to thermally induced pain, and diminished amplitude of the compound action potential in the caudal nerve. Coadministration of nerve growth factor prevented all of these signs of neurotoxicity. These findings suggest that administration of nerve growth factor may prevent certain toxic sensory neuropathies.
Long-term follow-up in toxic solitary autonomous thyroid nodules treated with radioactive iodine The long-term effects of radioiodine treatment on thyroid function in patients with a toxic solitary autonomous thyroid nodule were evaluated. Fifty-two patients received a therapeutic dose of 20 mCi of iodine-131 (131I). Duration of follow-up was 10 +/- 4 yr. Follow-up data included a biochemical evaluation of thyroid function. The failure rate (recurrent hyperthyroidism) was 2%. The incidence of hypothyroidism was 6% and was not related to the dose per gram of nodular tissue. Oral administration of 20 mCi of radioiodine is a simple and highly effective method for the treatment of patients with a toxic autonomous thyroid nodule. The risk of development of hypothyroidism is low if extranodular uptake of 131I is prevented. This can be achieved by not treating euthyroid patients, by no longer using injections of exogenous thyroid stimulating hormone in the diagnostic work-up of the patients and by always performing radioiodine imaging shortly before treatment.
Vaccination against tumor cells expressing breast cancer epithelial tumor antigen. Ninety-one percent of breast tumors aberrantly express an epithelial tumor antigen (ETA) identified by monoclonal antibody H23. Vaccinia virus recombinants expressing tumor antigens have considerable promise in the active immunotherapy of cancer, and we have evaluated the potential of vaccinia recombinants expressing the secreted (S) and cell-associated (transmembrane, T) forms of H23 ETA to elicit immunity to tumor cells expressing ETA. Tumorigenic ras-transformed Fischer rat fibroblast lines FR-S and FR-T, expressing the S or T form of H23 ETA, respectively, were constructed for use in challenge experiments. Expression of H23 ETA in these lines was confirmed by Western blotting and immunofluorescence. When challenged by subcutaneous seeding of tumor cells, 97% (FR-S) and 91% (FR-T) of syngeneic Fischer rats rapidly developed tumors that failed to regress. Vaccination with recombinant vaccinia virus expressing ETA-T prior to challenge prevented tumor development in 82% of animals seeded with FR-T cells but in only 61% of animals seeded with FR-S. The vaccinia recombinant expressing the S form was a less effective immunogen, and vaccination protected only 29-30% of animals from developing tumors upon challenge with either FR-S or -T cells. The increased immunogenicity of the recombinant expressing ETA-T was reflected in elevated levels of ETA-reactive antibody in vaccinated animals, confirming that secreted antigens expressed from vaccinia virus are less effective immunogens than their membrane-associated counterparts.
Characteristics of oculomotor disorders of a family with Joseph's disease. The oculomotor abnormalities of 12 patients of a large Japanese family with Joseph's disease were investigated and compared with those of 27 patients with olivopontocerebellar atrophy (OPCA). All 12 patients had limitation of upward gaze, impairment of convergence and horizontal gaze nystagmus. However, none had abnormalities of pupillary shape or light reflexes. Impairments of saccadic and pursuit eye movements were frequently present. Further, difficulty of eyelid opening, bulging eyes, impairment of optokinetic and caloric responses and square wave jerks were seen in some of the patients. The autopsy examination of 1 patient revealed marked neuronal loss in the oculomotor nucleus with preservation of the Edinger-Westphal nucleus and neuronal decrease, myelin loss and gliosis of the dorsal midbrain including superior colliculus, pretectum and posterior commissures. Disturbance of upward gaze, sparing of pupillary light reflexes and horizontal gaze nystagmus were frequent and early symptoms. The pattern of oculomotor disturbances is different from that of OPCA and evaluation of the oculomotor system is useful for clinical diagnosis of the disease.
Venous and arterial thrombosis in patients who received adjuvant therapy for breast cancer. The records of 2,673 patients randomized according to seven consecutive Eastern Cooperative Oncology Group (ECOG) studies of adjuvant therapy for breast cancer were reviewed for the occurrence of vascular complications. All protocols opened and closed between June 1977 and July 1987. The objectives of the present study were (1) to compare the frequency of vascular complications among patients who received adjuvant therapy for breast cancer with patients on observation, and (2) to estimate the contribution of chemotherapy and hormonal therapy to the occurrence of venous and arterial thrombi. The frequency of thrombosis, both venous and arterial combined, was 5.4% among patients who received adjuvant therapy and was 1.6% among patients on observation (P = .0002). Premenopausal patients who received chemotherapy and tamoxifen had significantly more venous complications than those who received chemotherapy without tamoxifen (2.8% v 0.8%, P = .03). Postmenopausal patients who received tamoxifen and chemotherapy had significantly more venous thrombi than those who received tamoxifen alone (8.0% v 2.3%, P = .03) or those who were observed (8.0% v 0.4%, P less than .0001). Premenopausal patients who received tamoxifen and chemotherapy had a 1.6% frequency of arterial thrombosis, significantly more than patients who received chemotherapy alone (1.6% v 0.0%, P = .004). The frequency of arterial thrombosis among postmenopausal patients was not significantly correlated with adjuvant therapy. In conclusion, patients who received adjuvant therapy for breast cancer had a 5.4% frequency of thromboembolic complications, significantly more than those who were observed. The combination of chemotherapy and tamoxifen was associated with more venous and arterial thromboembolic complications than chemotherapy alone in premenopausal patients and with more venous thrombi than tamoxifen alone among postmenopausal patients.
Endoscopic ventricular fenestration using a "saline torch". The fiberoptic endoscope has never gained popularity among neurosurgeons although it is ideally suited for navigating within the cerebral ventricles. Recent advances in optics and miniaturization make the application of endoscopy in neurosurgery more practical. The authors report eight children who underwent ventriculoscopic fenestration of symptomatic loculated cerebrospinal fluid (CSF) collections. These CSF collections were either isolated ventricular cysts or trapped lateral ventricles secondary to obstruction at the foramen of Monro. Cyst wall dissection was carried out with a "saline torch" dissector which was introduced through a working channel in the ventriculoscope. The torch was used to coagulate vessels and to sculpt large windows in cyst walls or in the septum pellucidum. Ventriculoscope-guided cyst fenestration can be performed safely and easily under direct vision. The technique may permit simplification of shunt systems in some patients and elimination of shunts in others.
Hemodynamic benefit of maintaining atrioventricular synchrony during cardiac pacing in critically ill patients. OBJECTIVE: To determine the hemodynamic effects of maintaining atrioventricular synchrony during emergency cardiac pacing in critically ill patients. DESIGN: Prospective, within patient double-blind study. SETTING: ICU or coronary care unit patients in a university hospital. PATIENTS: Forty (23 cardiac surgery, ten acute myocardial infarction, and seven general intensive care) seriously ill patients with severe symptomatic bradycardia. INTERVENTION: Initial randomization of patients to receive either a pacing mode where atrioventricular synchronization was maintained (atrioventricular pacing: atrial demand, atrioventricular sequential, atrioventricular universal) or a mode of pacing where atrioventricular synchrony was not preserved (ventricular demand pacing). MEASUREMENTS and MAIN RESULTS: The cardiac output increased from a mean of 4.5 +/- 1.7 L/min (95% confidence intervals: 4.0 to 5.0 L/min) during ventricular demand pacing to 5.3 +/- 1.7 L/min (95% confidence intervals: 4.9 to 5.9 L/min) during atrioventricular pacing (p less than .0001) despite trivial decreases in CVP from 14 +/- 4 mm Hg (95% confidence intervals: 13 to 15 mm Hg) to 13 +/- 5 mm Hg (95% confidence intervals: 12 to 15 mm Hg) and pulmonary artery occlusion pressure from 18 +/- 5 mm Hg (95% confidence intervals: 16 to 20 mm Hg) to 17 +/- 5 mm Hg (95% confidence intervals: 15 to 18 mm Hg). At the same time, mean arterial pressure (MAP) increased from 74 +/- 15 mm Hg (95% confidence intervals: 64 to 79 mm Hg) to 83 +/- 15 mm Hg (95% confidence intervals: 80 to 88 mm Hg) and left ventricular stroke work index from 22 +/- 10 g.m/m2 (95% confidence intervals: 19 to 25 g.m/m2) to 30 +/- 11 g.m/m2 (95% confidence intervals: 26 to 33 g.m/m2). There was no significant change in mean pulmonary artery pressure, pulmonary vascular resistance index, or systemic vascular resistance index. CONCLUSION: When cardiac pacing is required in critically ill patients, maintaining atrioventricular synchrony increases stroke volume, cardiac output, and MAP apparently with minimal effects on preload and afterload.
Short-term and long-term changes in renal function after donor nephrectomy. We retrospectively examined the effect of nephrectomy on renal function in 55 living related donors. Renal function was measured with 131iodine-orthoiodohippurate scans. All patients were studied preoperatively, and 1 week and 1 year postoperatively. In 20 patients 10-year followup was available. Compensatory hypertrophy was complete 1 week postoperatively: effective renal plasma flow of the remaining kidney was 32.5% higher than preoperatively. The increase remained stable for at least a year. The degree of compensatory hypertrophy was significantly greater in male patients (46.9% after 1 week) than in female patients (26.7%). Compensatory hypertrophy occurred in all age groups studied and it was most pronounced in patients less than 30 years old. In the patients followed for 10 years effective renal plasma flow decreased from 387.7 ml. per minute 1 week after nephrectomy to 367.4 ml. per minute at 10 years. This result is similar to the decrease seen in the normal population. According to our results, renal donation by living related persons does not lead to long-term decrease in renal function.
Spontaneous rupture of liver during pregnancy: current therapy. Spontaneous hepatic rupture secondary to severe pregnancy-induced hypertension is associated with a high rate of maternal and fetal mortality. Numerous types of surgical management have been described, but a uniform surgical approach has not been accepted. The purpose of this review was to examine modes of surgical therapy reported in the literature since 1976, as well as the 11-year experience at our institution. Twenty-eight cases were extracted from the literature and seven more were identified at our institution. The incidence in our population was one per 45,145 live births. Among 27 cases managed by packing and drainage, an 82% overall survival was achieved, whereas only 25% of eight patients undergoing hepatic lobectomy survived (P = .006). Hepatic hemorrhage with persistent hypotension unresponsive to blood products should be managed by evacuating the hematoma, packing the damaged liver, and draining the operative site. More aggressive surgical techniques, such as hepatic artery ligation or hepatic lobectomy, should be reserved for refractory cases.
A coproporphyria-like syndrome induced by glipizide. A 49-year-old man with a 1-month history of episodic, severe abdominal pain sought medical attention. The patient's history was remarkable for type II diabetes, for which glipizide therapy had been initiated 2 months earlier. No other medications were being taken at the time the paroxysms of pain began. During the episodes of pain, both examination of the abdomen and abdominal roentgenograms revealed normal findings. Initial assessment, including ultrasonography and computed tomographic scanning of the abdomen, upper gastrointestinal and colon roentgenograms, and esophagogastroduodenoscopy, revealed no cause of the pain. Empiric trials of famotidine, sucralfate, and antacids failed to relieve the pain. Both urine and fecal specimens collected after an attack demonstrated substantially increased coproporphyrins. The glipizide regimen was discontinued; 2 months later, the stool coproporphyrins had decreased to normal levels. At follow-up more than 1 year later, the patient had had no recurrence of abdominal pain. Although other orally administered hypoglycemic agents and other sulfa compounds have been reported to precipitate acute attacks of porphyria, to our knowledge this is the first such case associated with glipizide. We suggest that glipizide be added to the list of medications to be avoided in patients with porphyria.
Esophageal ultrasound and the preoperative staging of carcinoma of the esophagus. Esophageal ultrasound allows the esophageal wall to be viewed as five discrete layers. Lymph nodes are easily identified, and their size, shape, margin, and internal structure can be assessed. This provides an alternative method of preoperative (clinical) evaluation of the primary tumor [T] and the regional lymph nodes [N] of patients with carcinoma of the esophagus. Esophageal ultrasound was attempted in the clinical staging of 28 patients with carcinoma of the esophagus. Six patients (21%) were not assessed because of the inability to pass the esophageal ultrasound probe through the malignant stricture. The staging system for carcinoma of the esophagus developed by the International Union Against Cancer and the American Joint Committee on Cancer was used. Twenty-two patients had the true T determined by pathologic review of the resected esophagus. Esophageal ultrasound correctly identified T in 13 patients (59% accuracy). In four patients (18%) the disease was overstaged by esophageal ultrasound; all these patients had early T1 tumors confined to the submucosa. In five patients (23%) the disease was understaged by esophageal ultrasound; all of these patients had advanced tumors (four T3 and one T4) that invaded beyond the esophageal wall. Seven of the nine incorrect esophageal ultrasound determinations were called T2 (three T1, three T3, one T4), which suggests that the borders of the muscularis propria require careful attention when evaluated by esophageal ultrasound. Twenty patients had the true N determined by pathologic review of the resected specimen. Esophageal ultrasound correctly identified N in 14 patients (70% accuracy). Three patients were falsely identified as having N1 disease and three were falsely identified as having N0 disease. The sensitivity, specificity, positive predictive value, and negative predictive value for N assessment by esophageal ultrasound were 70%. Esophageal ultrasound provides an alternative method of visualization of the esophageal wall and regional lymph nodes. Our early experience shows promise for esophageal ultrasound in the clinical staging of carcinoma of the esophagus.