shukoor65/lab-rag-model huggingface dataset:
Magnetic resonance imaging of spinal trauma. A retrospective series of 118 magnetic resonance examinations of 110 patients who had sustained previous spinal trauma is reported. Examinations performed within 3 weeks of trauma showed extraspinal soft tissue (including ligamentous) injury in 48% and intraspinal lesions in 61% (mostly consisting of extradural haematoma and spinal cord contusion). In examinations performed more than 3 weeks after injury intraspinal abnormalities were shown in 51% and these represented spinal cord compression, atrophy, myelomalacia and syringohydromyelia. Magnetic resonance imaging has the unique capability of displaying non-invasively the late sequelae of spinal trauma permitting simultaneous evaluation of the extra-spinal soft tissues, vertebral column and spinal cord. It is therefore recommended as the technique of choice in the investigation of patients who have sustained previous spinal injury, particularly those with neurological deficit. In the acute phase potentially remediable causes of neurological impairment such as disc herniation or extradural haematoma can be identified. Signal changes in the cord may allow the prognosis for neurological recovery to be established. In the later stages sequelae such as cord atrophy, myelomalacia and syringohydromyelia are accurately identified and surgical therapy may be guided, where appropriate.
Altered density of glomerular binding sites for atrial natriuretic factor in bile duct-ligated rats with ascites. The renal response to atrial natriuretic factor is blunted in cirrhosis with ascites. This might be due to alterations of renal receptors for atrial natriuretic factor. Therefore density and affinity of glomerular atrial natriuretic factor binding sites of bile duct-ligated rats with ascites (n = 10) and of sham-operated controls (n = 10) were determined. Glomerular atrial natriuretic factor binding sites were identified to be of the B-("biologically active") and C-("clearance") receptor type. Discrimination and quantitative determination of B and C receptors for atrial natriuretic factor were achieved by displacement experiments with atrial natriuretic factor(99-126) or des(18-22)atrial natriuretic factor(4-23), an analogue binding to C receptors only. Density of total glomerular atrial natriuretic factor binding sites was significantly increased in bile duct-ligated rats (3,518 +/- 864 vs. 1,648 +/- 358 fmol/mg protein; p less than 0.05). This was due to a significant increase of C-receptor density (3,460 +/- 866 vs. 1,486 +/- 363 fmol/mg protein; p less than 0.05), whereas density of B receptors was not significantly different in bile duct-ligated rats (58 +/- 11 vs. 162 +/- 63 fmol/mg protein). Affinity of atrial natriuretic factor to its glomerular binding sites did not differ significantly between both groups. These data suggest that an altered glomerular atrial natriuretic factor receptor density could be involved in the renal resistance to atrial natriuretic factor in cirrhosis with ascites.
The change in patterns of relapse in medulloblastoma. The authors reviewed 89 patients treated for cerebellar medulloblastoma between 1970 and 1989 to determine the impact of changing treatment (high-dose posterior fossa radiation therapy and chemotherapy) on the pattern of failure in medulloblastoma. Between 1970 and 1983, 50 patients (median follow-up, 110 months) were treated with surgery and postoperative craniospinal irradiation (CSI). Nineteen of the 50 (38%) recurred in the central nervous system (CNS). Isolated systemic (bone) metastases occurred in six. The median time to the development of bone metastases was 12 months. Since 1984, 39 patients (median follow-up, 27 months) were treated with preradiation chemotherapy consisting of cisplatin and vincristine for 9 weeks before initiation of CSI. Nine of the 39 (23%) patients recurred in the CNS. There were no systemic failures in this cohort. The actuarial 5-year disease-free survival was 55 +/- 7% for the earlier cohort and 72 +/- 8% for the later cohort (P equals 0.3). Posterior fossa recurrence was associated with radiation therapy to this area. The cumulative incidence of posterior fossa relapse was 50 +/- 13% in patients who received less than 5300 cGy and 18 +/- 7% in those who received 5300 cGy or more (P equals 0.005). All six bone relapses were in patients treated with CSI alone and 5300 cGy or more to the posterior fossa for a 5-year cumulative incidence of bone metastases of 18 +/- 7% compared with 0% for patients treated with 5300 cGy or more and chemotherapy (P equals 0.03). The authors concluded that high-dose radiation therapy has altered the pattern of relapse with an increase in systemic recurrence after radiation therapy alone that is now equivalent to the risk of recurrence in the posterior fossa. Chemotherapy may be indicated in an attempt to decrease this high risk of systemic metastases.
Long-term follow-up after prosthetic replacement of the superior vena cava combined with resection of mediastinal-pulmonary malignant tumors. The contraindication to curative excision of mediastinal and pulmonary cancers because of invasion of the superior vena cava is now challenged by the existence of vascular prostheses that are suitable for venous replacement. Between 1979 and 1990 22 patients underwent resection of lung cancer (n = 6) or malignant mediastinal tumors (n = 16) involving the superior vena cava. Resection was done with concomitant venous reconstruction, and polytetrafluorethylene grafts were used. All bronchogenic carcinomas necessitated right pneumonectomy, whereas the excision of mediastinal tumors had to include pulmonary resections in nine patients (five lobectomies and four sublobar resections) and the right phrenic nerve in 12 patients. Venous reconstruction was performed by interposition of a large polytetrafluoroethylene graft between the proximal and cardiac ends of the superior vena cava (n = 8), or between one (n = 10) or both brachiocephalic veins (n = 4) and the right atrium. One patient died postoperatively (4.5%), and another had mediastinitis that was successfully treated by omentopexy. Chemotherapy was administered preoperatively to five patients and postoperatively to seven patients; radiotherapy was administered to two and 10 patients, respectively. The overall actuarial survival rate is 48% at 5 years, with 11 patients presently alive. The survival rate of patients with mediastinal tumors is 60% at 5 years. Among the patients with lung cancer, two with N1 disease are alive at 16 and 51 months, and one died at 38 months; the two patients with N2 disease died at 6 and 8 months. Only one graft occlusion occurred in the postoperative period; another occurred 14 months after operation and was precipitated by insertion of a central venous catheter. The patency of all remaining grafts was demonstrated after an average time of 23 (1 to 98) months. On the basis of these results, polytetrafluoroethylene graft replacement of the superior vena cava should be part of the planning and execution of radical excision with curative intent of mediastinal and right pulmonary malignant tumors that are not present with other contraindications, such as pleural or distant metastasis and severe systemic disease.
Tolerance of gastric mucosal flap to postoperative irradiation. When malignant lesions of the oral cavity, base of tongue, and oropharynx are treated with radical resection, adequate reconstruction is required. The free gastric mucosal flap with microvascular transfer is being used with increasing frequency at Washington University Medical Center. Because of the advanced nature of the primary lesions, most patients also require postoperative radiation therapy. In this paper the tolerance of the gastric mucosal flap to postoperative radiation therapy is reviewed. The changes resulting from radiation therapy in the mucosal flap were found to be acceptable, and no major complications were encountered.
Intravenous heme-albumin in acute intermittent porphyria: evidence for repletion of hepatic hemoproteins and regulatory heme pools. The purpose of this study was to assess effects of heme administered intravenously, complexed to human serum albumin, on activities of the hepatic hemoproteins, cytochrome(s) P-450, and tryptophan pyrrolase, and on the size of the heme pool that regulates activity of 5-aminolevulinate synthase. Effects were compared in six normal women and four women with acute intermittent porphyria. All porphyric subjects over-excreted heme precursors and had histories of acute neurovisceral porphyric attacks. All subjects were placed on a constant daily diet that included at least 3 g carbohydrate/kg body weight and sufficient total intake to provide 1.4 times the estimated resting energy expenditure. Urinary excretions of 5-aminolevulinate, porphobilinogen, porphyrins, and metabolites of tryptophan were measured daily before, during, and after infusions of heme-albumin. In the porphyric subjects, intravenous heme [4 mg (6.1 mumol)/kg body weight (BWt) with equimolar albumin], given daily for 4 days, markedly reduced overexcretion of 5-aminolevulinate, porphobilinogen, and porphyrins, indicating repletion of the regulatory heme pool. The heme infusions also decreased mean urinary excretion of 5-hydroxyindoleacetic acid from 4.9 to 2.9 mg/g creatinine per day, suggesting increased activity of hepatic tryptophan pyrrolase, the rate-controlling enzyme for metabolism of tryptophan to products not in the serotonin-5-hydroxyindoleacetic acid pathway. Heme-albumin infusions were without detectable effects on excretions of heme precursors or tryptophan metabolites in normal subjects. In contrast, in both normals and porphyrics, heme-albumin infusions significantly increased rates of antipyrine metabolism (by 159% and 330%, respectively), suggesting increased activities of cytochrome(s) P-450 were produced by the infusions. The infusions were well tolerated; no subject developed thrombophlebitis or bleeding. We conclude that such infusions are safe and effective in repleting deficient heme pools and hemoproteins in patients with acute porphyria, and that activities of cytochrome(s) P-450 in normal subjects may also be increased by heme administration. The therapeutic effect of heme in acute porphyria probably relates to its ability to decrease overproduction of precursors of heme or serotonin, as the result of its increasing critical cellular heme pools.
Anti-V region antibodies as "almost clonotypic" reagents for the study of cutaneous T cell lymphomas and leukemias. Despite recent advances in the understanding of normal T lymphocyte immunobiology, there has been little progress in characterizing the non-HTLV cutaneous T-cell lymphomas and leukemias (CTCL) Mycosis Fungoides and Sezary syndrome. The two major impediments to in vitro studies of these malignancies have been the contamination of CTCL cells with normal T cells and the inability to induce a vigorous proliferative response or establish long-term cultures with standard T-cell mitogens. The ideal reagent for identifying CTCL cells in a given patient would be tumor specific. Although a monoclonal antibody to the clonotypic antigen receptor on CTCL cells would approach this ideal, it is not currently feasible to generate such antibodies for each CTCL patient. As a compromise, we chose to test an "almost clonotypic" reagent by examining whether monoclonal antibodies directed at the variable (V) region of the T-cell antigen receptor could be applied to CTCL. We identified three Sezary patients, who by standard T-cell phenotype and Southern blot analysis for clonality had a virtually pure peripheral blood population of leukemic cells (PBL). We then screened the PBL of these patients with a panel of seven commercially available monoclonal anti-V region antibodies and found one patients' cells reacted greater than 99% with alpha V beta 5. The other patients' cells were non-reactive. In addition, we utilized a solid-phase system to cross-link V beta 5 on the one CTCL patients' PBL cells, and found that they proliferated vigorously in the presence of 10 units of IL-2 and IL-4. Parallel cultures have been maintained for one month by restimulation twice a week. These findings suggest that anti-V region antibodies should prove useful for investigating the immunobiology of CTCL.
Double-blind, placebo-controlled study of the therapeutic use of recombinant human erythropoietin for anemia associated with chronic renal failure in predialysis patients. The US Recombinant Human Erythropoietin Predialysis Study Group [published erratum appears in Am J Kidney Dis 1991 Sep;18(3):420] One hundred seventeen patients with anemia related to chronic renal failure not severe enough to require maintenance dialysis were randomly assigned to receive recombinant human erythropoietin (rHuEPO; 50, 100, or 150 U/kg body weight) or placebo intravenously (IV) three times a week for 8 weeks or until their anemia was corrected. Correction of anemia (hematocrit of 40% for males, 35% for females) occurred in 87% of those given 150 U/kg, 64% of those given 100 U/kg, 46% of those given 50 U/kg rHuEPO and in 3% of the placebo group. Energy levels and work capacity improved significantly in the group with corrected anemia compared with the group with uncorrected anemia. rHuEPO appeared to be well tolerated. There was no evidence that rHuEPO therapy accelerated the deterioration of renal function as measured by serum creatinine and reciprocal of serum creatinine compared with placebo treatment. However, it is essential that blood pressure and hematocrit be carefully monitored, particularly in hypertensive patients, to prevent the development of complications associated with hypertension.
Preeclampsia as the great impostor. In contrast with a generation ago when preeclampsia was misdiagnosed as medical or surgical disease unrelated to pregnancy, today's diagnostic errors are those that consider surgical and medical problems as either pregnancy-induced hypertension or as the hemolysis, elevated liver enzymes, and low platelet count syndrome. Eleven case histories are presented of significant medical or surgical problems that were initially diagnosed as hemolysis, elevated liver enzymes, and low platelet count syndrome or pregnancy-induced hypertension. The incorrect diagnosis of medical-surgical cases during pregnancy often meant that appropriate therapy was delayed and that the rate of iatrogenic prematurity was increased.
IgA nephropathy in non-cirrhotic portal hypertension. Renal glomerular changes are a well recognised complication of cirrhosis and are frequently characterised by mesangial IgA deposition. We report a patient with non-cirrhotic portal hypertension who developed IgA nephropathy and a nephrotic syndrome with renal histological changes classically associated with cirrhosis. Splenectomy with resection of a splenic artery aneurysm resulted in remission of the nephrotic syndrome. This case illustrates the factors which contribute to the pathogenesis of IgA nephropathy in liver disease.
Folk terminology for diarrhea in rural Bangladesh. Diarrhea, a descriptive term used in medical science for a variety of clinical diseases, denotes an illness that is categorized differently and known by numerous terms in various cultures. These diversified classifications and terminologies are based on the symptoms of diarrheal disorders, their perceived etiology, and their treatment. In Bangladesh, four types of illnesses with names derived from folk terminology have been identified for which the clinical symptoms resemble those of diarrhea. These include dud haga, which is due to ingestion of breast milk by infants; ajirno, which is due to overeating; amasha, a mucoid diarrhea; and daeria, which is severe watery diarrhea or cholera. Use of the word diarrhea in epidemiologic evaluations was discovered to be problematic; people confused this term with daeria, which accounted for only 5% of all episodes of diarrhea. The implications of such epidemiologic information for a large-scale program of oral rehydration therapy are also discussed.
31P localized magnetic resonance spectroscopy of head and neck tumors--preliminary findings. Magnetic resonance imaging (MRI) is a powerful tool for accurate assessment of the anatomic extent of head and neck neoplasms. The development of methods for spatial localization by use of multiply tuned radio frequency coils that permit the measurement of multiple nuclear MR spectra (1H and 31P) from precisely defined volumes of interest has provided a basis for integrating spectroscopy into the clinical MRI examination. This offers a means for noninvasive monitoring of relative concentrations of mobile metabolites within a tumor. With the use of imaging to determine proper coil placement, a test-retest variance of about 17% is seen on MR spectroscopy. Data are presented from MRI/MRS studies for four head and neck lesions: (1) a squamous cell carcinoma of the lip; (2) a juvenile angiofibroma extending into the nasal cavity; (3) a massive chondrosarcoma of the nasal septum; and (4) a cervical nodal metastasis of a squamous cell carcinoma of the pharynx. Spectra are evaluated by comparison of relative concentrations of phosphorus compounds. The concentrations of phosphomonoesters and phosphodiesters are significantly higher in the neoplasms studied than in normal skeletal muscle. The developing role of integrated MRI/MRS to monitor the response of malignant neoplasm to radiation therapy is discussed.
Metabolic responses to swimming exercise in Streptococcus pneumoniae infected rats. The present study was performed to determine whether alterations in fuel reserves or energy substrate utilization might explain the performance decrements that occur in bacterial infections. Male Fisher-Dunning rats were studied at 24, 48, and 72 h after inoculation with Streptococcus pneumoniae. Rats were either sedentary or subjected to a 2-h swimming session at these three time points (N = 10 in each group). A more than 60% reduction (P less than 0.01) in performance capacity was observed on day 3 of infection compared with that in noninfected controls. This infection in the rat is characterized by fever (P less than 0.01), depression of plasma zinc (P less than 0.01) and free fatty acid (FFA) levels (P less than 0.01), inhibition of the two- to threefold increase in fasting ketonemia, and a decreased (NS) insulin:glucagon ratio, indicating a catabolic state. Glycogen stores were reduced in the heart (47%), liver (43%), and skeletal muscles (39%) but not in the carcass. Superimposed exercise resulted in a further reduction but not depletion of liver, muscle, and carcass glycogen stores, a less pronounced lactic acid accumulation, and a lower oxygen debt. However, plasma FFA and ketone body levels were still maintained or even elevated, suggesting that fat is supplied as fuel during swimming exercise in this infection. Thus, results indicate that unavailability of energy substrates or lactacidosis is not limiting for performance capacity during this severe infection.
Congestive heart failure. New frontiers. Congestive heart failure is a common syndrome with high mortality in its advanced stages. Current therapy includes the use of vasodilator drugs, which have been shown to prolong life. Despite current therapy, mortality remains high in patients with severe heart failure. Potent new inotropic vasodilators have improved ventricular performance but have not prolonged life in patients with end-stage heart failure. Serious arrhythmias are implicated in the sudden deaths of 30% to 40% of patients with severe heart failure, but the benefits of antiarrhythmic therapy have not been established. Upcoming trials will address this question. Ventricular remodeling and progressive dilatation after myocardial infarction commonly lead to congestive heart failure; early unloading of the ventricle with an angiotensin-converting enzyme inhibitor may attenuate these events. These findings support the concept that angiotensin-converting enzyme inhibitors may be useful in managing heart failure of all degrees of severity, including left ventricular dysfunction and end-stage heart failure. Part of the damage that may occur with acute myocardial infarction, particularly in this era of thrombolysis therapy, is reperfusion injury, which may be mediated by oxygen-derived free radicals. Better knowledge of the mechanisms and treatment of myocardial infarction, the leading cause of congestive heart failure, may help prevent or attenuate the development of this syndrome.
Management of severe fibrocystic disease of the breast with leuprolide acetate. Symptoms of severe fibrocystic disease of the breast were successfully ameliorated in two patients as a result of treatment with daily subcutaneous LA without adverse effects. A state of drug-induced hypogonadotropic hypogonadism appears to be responsible for the clinical effect and is further suggestive of the hormonal dependence of this common disorder.
Safety of surgical procedures performed by residents. The outcome of surgical procedures on the gallbladder performed by surgical residents in a university hospital was compared with the outcome of those performed by the attending staff. More than 60% of the operations (643/1084) were done by residents under the direct supervision of the attending surgeon. We found no differences in the rate of technical complications, postoperative morbidity and mortality, or length of hospitalization between the two groups. Thus, resident surgery under appropriate guidance is safe and does not compromise the quality of patient care or operative outcome.
Acetylcholine regulates pancreastatin secretion from the human pancreastatin-producing cell line (QGP-1N). Studies were made of pancreastatin (PST) secretion from a human PST-producing cell line (QGP-1N) in response to various secretagogues. Cells with immunoreactivity for PST were observed in monolayer cultures of QGP-1N cells. Carbachol stimulated PST secretion and the intracellular Ca2+ mobilization concentration dependently in the range of 10(-6)-10(-4) M. The PST secretion and Ca2+ mobilization induced by carbachol were inhibited by atropine. The calcium ionophore (A23187) stimulated PST secretion. However, cholecystokinin and gastrin-releasing peptide did not stimulate either PST secretion or Ca2+ mobilization. Secretin also did not stimulate PST secretion. The glucose concentration in the culture medium had no effect on PST secretion. These results suggest that PST secretion is mainly regulated by acetylcholine through a muscarinic receptor, and that an increase in intracellular Ca2+ plays an important role in stimulus-secretion coupling in QGP-1N cells.
Delayed visual loss due to trauma of the internal carotid artery. The group of six patients in this study experienced delayed visual loss following head trauma. Visual loss occurred from 1 day to 13 years after the initial injury. All patients suffered indirect trauma to the internal carotid artery resulting in formation of either an aneurysm or pseudoaneurysm or a carotid-cavernous fistula. Review of the radiologic and clinical findings was performed in six patients. The diagnosis was established by computed tomography, magnetic resonance imaging, and angiography. All patients had follow-up clinical evaluation and imaging studies. Treatment by neurosurgical or interventional neuroradiologic procedures resulted in significant visual improvement in five patients. Different pathophysiologic mechanisms could be correlated with the delayed visual loss produced by the two types of lesions. The pathologic changes associated with the aneurysms/pseudoaneurysms included direct compression of optic nerves and/or chiasm and intracranial hematoma. A carotid-cavernous fistula caused delayed visual loss by either hematoma at the orbital apex or compression of the chiasm and/or optic nerves by saccular dilatation of the cavernous sinus. The delayed onset of decreased vision following head trauma should alert the physician to the possibility of a traumatic aneurysm/pseudoaneurysm or a carotid-cavernous fistula. Different neuro-ophthalmologic symptoms can usually be correlated with the pathologic changes demonstrated by neuroimaging procedures.