shukoor65/lab-rag-model huggingface dataset:
Malignant astrocytomas: focal tumor recurrence after focal external beam radiation therapy. Hochberg and Pruitt have reported glioblastomas recurring within 2 cm of the primary site in 90% of patients after whole-brain radiation therapy. They suggested that computerized tomography (CT) scan accuracy would permit smaller radiation fields. A treatment protocol with smaller-field focal brain irradiation following surgical resection is reported. The first 4500 cGy of radiation is focused to within a 3-cm margin around the tumor, with a 1500-cGy boost within a 1.5-cm margin. Forty-two patients with grade III or IV astrocytoma, treated with focal brain radiation therapy were reviewed retrospectively to assess patterns of tumor recurrence. Thirty patients received intra-arterial bromodeoxyuridine (BUdR) radiosensitization with focal brain radiation therapy, and 12 patients underwent conventional focal brain radiation therapy. Tumor margin was defined on preoperative and recurrence CT scans as the contrast-enhanced area; these were traced on acetate templates and compared with each other and with the actual scans. In all 42 patients, the lesion recurred within a 2-cm margin of the original tumor. Four patients had two recurrent areas: the second area was within the 2-cm margin in two, and outside this margin in two. These results are similar to those of Hochberg and Pruitt. It is suggested that focal irradiation is now the optimal treatment for malignant astrocytoma. Since recurrences continue to be within the irradiated volumes, it appears that higher focal doses of radiation are appropriate for clinical treatment trials of malignant astrocytomas.
Abnormal vitamin B12 metabolism in human immunodeficiency virus infection. Association with neurological dysfunction. An increased prevalence of vitamin B12 deficiency has been reported in patients infected by the human immunodeficiency virus (HIV). We report an unexpectedly high prevalence (20%) of such abnormal vitamin B12 metabolism in a population of HIV-infected patients referred for neurological evaluation. This abnormality was associated with both peripheral neuropathy and myelopathy. A majority of those treated with cyanocobalamin had a therapeutic response. Selected neuropathological results suggest a relationship between vitamin B12 deficiency and vacuolar myelopathy. Vitamin B12 deficiency may be a frequent and treatable cause of neurological dysfunction in patients with HIV infection.
Photodynamic killing of human squamous cell carcinoma cells using a monoclonal antibody-photosensitizer conjugate. We have developed procedures in which the photosensitizer benzoporphyrin derivative monoacid ring A (BPD) can be covalently linked to carrier molecules of modified polyvinyl alcohol (PVA) to produce water-soluble PVA-BPD conjugates with a molecular mass in the range of 30 kd. These carriers can subsequently be covalently linked to monoclonal antibodies (MoAbs) using heterobifunctional linking agents. We describe here such a conjugate in which the MoAb (5E8) has specificity for a glycoprotein detected on human squamous cell carcinomas of the lung. We provide evidence that the conjugates produced were covalently linked and retained both their photosensitizing and antigen-binding activities. We show further that the MoAb-PVA-BPD conjugate, in the presence of 10% fetal calf serum, exhibited highly enhanced phototoxic killing of the target cell line (A549) over that exhibited by free BPD or a control MoAb-PVA-BPD conjugate. These results demonstrate, therefore, both the selectivity and specificity of this MoAb conjugate.
Disseminated leiomyosarcoma in a child with acquired immune deficiency syndrome. A child with disseminated leiomyosarcoma and acquired immune deficiency syndrome (AIDS) is reported. She was originally believed to have peptic ulcer disease by radiographic and endoscopic evaluation but was found subsequently to have hypergastrinemia, hypochlorhydria, and a smooth muscle tumor. Leiomyosarcoma in children and its evolution in AIDS are discussed.
Improvement of cyclosporin absorption in children after liver transplantation by means of water-soluble vitamin E. Many childhood recipients of liver transplantation require massive doses of cyclosporin to achieve therapeutic blood concentrations of the drug. The impaired absorption of this strongly lipophilic drug may be due to reduced intestinal absorptive area, suboptimal mixing of the drug with hepatobiliary secretions, or residual cholestasis. Improvement of cyclosporin absorption was sought by means of oral coadministration of d-alpha-tocopheryl-polyethylene-glycol-1000 succinate (TPGS), a water-soluble form of vitamin E which can form micelles. 25 mg/kg daily of TPGS was given to six paediatric liver transplant recipients and one young adult with severe hepatobiliary graft-vs-host disease after bone-marrow transplantation, who required 29-136 mg/kg cyclosporin daily to achieve therapeutic cyclosporin blood concentrations. Five responded; the oral cyclosporin dose could be reduced by 40-72% within 2 months. In addition, intravenous cyclosporin was stopped in two of the responders. In the two non-responders the cyclosporin doses at entry were similar to those in the responders after TPGS treatment. Oral cyclosporin absorption tests correctly predicted the outcome of treatment in three responders and one non-responder tested. Treatment with TPGS to enhance cyclosporin absorption might be a useful way of reducing the high cost of immunosuppression in paediatric liver transplant recipients.
Effect of coronary reocclusion after initial reperfusion on ventricular function and infarct size. Reocclusion of a coronary artery after thrombolytic therapy occurs in approximately 12% to 33% of patients; however, there are few experimental data concerning reocclusion. Accordingly, to compare the effects of reocclusion versus sustained occlusion on the myocardium, a canine model (n = 12) of 2 h of left circumflex artery occlusion, 1 h of reperfusion and 1 h of reocclusion was studied. In a control group (n = 11), 3 h of circumflex artery occlusion was followed by 1 h of reperfusion. As a result, both groups had the same total duration of ischemia (3 h) and reperfusion (1 h). Hemodynamic measurements, radioactive microsphere injections and two-dimensional echocardiography were performed at baseline, occlusion and reperfusion for both groups and at the end of reocclusion for the experimental group. In vivo risk area was determined with Evans blue dye and infarct size with triphenyltetrazolium staining methods. Similar decreases in myocardial blood flow after coronary occlusion and similar reperfusion blood flows occurred in both groups. Despite intervening reperfusion in the reocclusion group, no significant difference was found in the infarct size/risk area ratio between the reocclusion and control groups (54.5 +/- 6.9% vs. 48.4 +/- 5.1%, respectively, p = NS). Two-dimensional echocardiography demonstrated a similar degree and extent (159 +/- 9 degrees vs. 153 +/- 12 degrees, p = NS) of left ventricular dysfunction with both the occlusion and reocclusion. In addition, there were no significant differences in global or regional left ventricular function between the two groups. However, reocclusion after reperfusion did produce a further deterioration in ischemic zone wall thickening (9.5 +/- 2.0% to 0.7 +/- 1.8%, p less than 0.001).
Hepatocellular carcinoma: treatment with a combination therapy of transcatheter arterial embolization and percutaneous ethanol injection. In an attempt to obtain complete tumor necrosis in large hepatocellular carcinoma (HCC) lesions, the authors studied the clinical and histologic findings of a new combination therapy, percutaneous ethanol injection (PEI) with transcatheter arterial embolization (TAE) (pretreatment with TAE and subsequent PEI) in 15 patients with a single, large (3.0-9.0 cm in diameter), encapsulated lesion of HCC. Two weeks after TAE, PEI was performed under ultrasound guidance. A total of four to 11 injections were administered at a rate of one injection twice a week. During the follow-up period (range, 7-23 months), all lesions were reduced in size and no evidence of HCC was present at contrast material-enhanced computed tomography or angiography in nine of 11 patients who did not subsequently undergo surgery. Six patients had a follow-up of 1 year or more, for a 1-year survival rate of 100%. Four patients subsequently underwent surgical resection; complete necrosis of the tumor was observed in all four. The authors conclude that a combination of PEI and TAE is an appropriate treatment for patients with large, encapsulated HCC lesions who are poor surgical risks.
Simultaneous in situ genotyping and phenotyping of human papillomavirus cervical lesions: comparative sensitivity and specificity. The sensitivity and specificity of immunocytochemistry were compared with those of non-isotopic in situ hybridisation (NISH) for the direct detection of human papillomaviruses in biopsy specimens. Four monoclonal antibodies raised to the capsid protein of HPV16 were less specific than NISH: all four reacted with lesions containing HPV33, and HPV18. Absolute discrimination of HPV types, therefore, was not possible with the monoclonal antibodies used in this study. The relative sensitivities of these antibodies were also lower than NISH. Sequential immunocytochemistry and NISH on the same section showed that 2.9-13.0 times as many cells were positive by NISH than by immunocytochemistry using the most sensitive monoclonal antibody. These data indicate that NISH has higher diagnostic specificity and sensitivity than immunocytochemistry using monoclonal antibodies to the HPV16 capsid protein.
Intestinal mucosal permeability in inflammatory rheumatic diseases. II. Role of disease. Gut permeability as measured by the 51Cr-EDTA resorption test was determined in 56 patients with rheumatoid arthritis (RA), 73 patients with spondyloarthropathies (SpA), 18 patients with inflammatory bowel disease (IBD) and 97 controls (42 patients with no inflammatory rheumatic diseases and 55 healthy controls). Gut permeability was found to be increased in the 3 patient groups, partially due to the intake of antiinflammatory drugs. When only patients not taking these drugs were considered, an increased gut permeability was found in patients with SpA and IBD. In patients with RA gut permeability could not be evaluated as they were all taking antiinflammatory medication. Ileocolonoscopy with biopsies of the gut was performed in 62 of the 73 patients with SpA and disclosed subclinical gut inflammation in 21. No difference in gut permeability was found between patients with or without gut inflammation. However, when the type of gut inflammation was considered, a significant increase of gut permeability was found in patients with chronic gut inflammation compared with patients presenting acute lesions. Our findings again suggest that the chronic gut inflammation seen in SpA is fundamentally different from acute gut inflammation and possibly related to the gut inflammation of IBD.
Positron emission tomography of pituitary macroadenomas: hormone production and effects of therapies. Positron emission tomography with [18F]fluorodeoxyglucose (FDG) was carried out in 24 patients with pituitary macroadenomas (32 studies) to assess the glucose utilization of these tumors in vivo. The adenoma metabolic index, which is the ratio of FDG uptake of tumor to a whole brain slice, was calculated. Comparisons were made between tumor uptake of FDG and hormone secretion and response to therapies. In each positron emission tomography study, the macroadenoma could be easily identified visually as an area of increased FDG uptake near the region of the sella. FDG uptakes were highest for nonfunctional adenomas, and the prolactin, growth hormone, and thyroid-stimulating hormone-producing groups displayed similar levels of glucose metabolism. The adenoma metabolic index for all tumors averaged 1.3, ranging from 0.3 for a thyroid-stimulating hormone adenoma to 3.5 for a nonfunctional tumor. Tumors did not exhibit metabolic rates that could characterize the type of hormone produced. Recurrent macroadenomas displayed metabolism similar to tumors not operated on, whereas irradiated adenomas showed lower glucose uptake than nonirradiated tumors. Drug therapy with bromocriptine or the long-acting somatostatin analogue octreotide also decreased the glucose utilization of the tumor. There was no correlation between the amount of hormone produced and the adenoma metabolic index when a group of tumors was analyzed. Patients scanned more than once, however, demonstrated changes in hormone levels that changed or did not change in parallel with tumor metabolism. Thus, positron emission tomography offers the potential capability for predicting and defining the growth of pituitary adenomas. This may be of particular value when plasma hormone assays and conventional imaging techniques prove inadequate for monitoring patient response to therapy.
Hypertonic saline dextran resuscitation during the initial phase of acute endotoxemia: effect on regional blood flow. BACKGROUND AND METHODS: Small-volume resuscitation by means of bolus application of hypertonic saline solutions has been demonstrated to restore central hemodynamics and regional blood flow in severe hemorrhagic and traumatic shock. The aim of this study was to elucidate the potential of this new concept for treatment of profound hypovolemia and microcirculatory deterioration associated with sepsis and endotoxic shock. In a porcine model of acute hyperdynamic endotoxemia (elicited by continuous iv infusion of Salmonella abortus equi endotoxin for 3.5 hrs), small-volume resuscitation applying hypertonic-hyperoncotic solutions was analyzed for its effect on central hemodynamics, oxygen delivery (Do2), and regional blood flow. Fluid therapy was initiated when the pulmonary artery occlusion pressure (PAOP) tended to decrease (at 43 to 52 mins of endotoxemia), and consisted of 4 mL/kg bolus infusion of either 7.2% sodium chloride, 10% dextran, or 10% dextran in 7.2% sodium chloride; thereafter, PAOP was maintained by controlled infusion of 6% dextran-60. In a control group, 6% dextran-60 was given without preinjection of hypertonic-hyperoncotic solutions. RESULTS: On small-volume resuscitation, cardiac index significantly increased within 5 mins in all groups, while mean arterial pressure remained unchanged. Fluid requirements were significantly reduced after small-volume resuscitation and the hyperdynamic circulatory state was maintained until the end of the observation period; Do2 as well as blood flow to heart, kidneys, and splanchnic organs remained high. CONCLUSION: Small-volume resuscitation by means of hypertonic saline-dextran proved the most effective, and seems to be an attractive supportive therapy to prevent microcirculatory failure in sepsis and endotoxemia.
The importance of preoperative evaluation of the subclavian vein in dialysis access planning. Adequate venous outflow is critical to the proper function of a vascular-access graft (arteriovenous fistula) used for chronic hemodialysis. Stenosis of the subclavian vein can significantly compromise this venous outflow. The development of such subclavian vein stenoses has been associated with the prior placement of temporary subclavian vein dialysis catheters. We evaluated the importance of preoperative detection of these stenoses before placement of a permanent vascular-access graft in the upper extremity. Upper extremity venography was performed before placement of a permanent vascular-access graft in 43 patients. A total of 62 extremities were evaluated. A 40% prevalence of moderate or severe subclavian vein stenosis was found in patients with prior or existing temporary dialysis catheters in the subclavian vein. No stenoses were found in patients without a history of dialysis catheters in the subclavian vein. This difference in the prevalence of subclavian vein stenosis is statistically significant (p less than .001). In no case was the stenosis suspected clinically. Before placement of a permanent vascular-access graft, the subclavian vein should be evaluated in all patients with a history of a temporary dialysis catheter in the subclavian vein. The use of sites other than the subclavian vein for temporary dialysis is strongly encouraged.
Plasma gastrin and cholecystokinin response after pylorus-preserving pancreatoduodenectomy with Billroth-I type of reconstruction. Plasma gastrin and cholecystokinin (CCK) responses were measured after a pancreatoduodenectomy (PD) using the Billroth-I type reconstruction combined with distal partial gastrectomy (standard PD) and combined with preservation of the pylorus and the duodenal bulb (PPPD). Six unoperated patients, 4 men and 2 women, were studied as control subjects. Basal plasma levels of gastrin were significantly higher in controls than in patients who had a standard PD (p less than 0.05) and gastrin responses to a meal were also blunted in these patients. In contrast basal and postprandial levels of gastrin after PPPD were significantly higher than these found in patients with standard PD (p less than 0.05). Postprandial gastrin response after PPPD were similar in pattern to these found in controls. Integrated gastrin release after PPPD was less than that of the control but was significantly greater than that in patients with standard PD. Basal plasma levels of CCK in the patients after the standard PD were significantly lower than in controls and significantly higher postprandial levels of CCK were found after PPPD compared to standard PD (p less than 0.05). However integrated CCK from 0 to 120 minutes were not significantly different between PPPD and standard PD groups. Based on these observations concerning hormonal release of gastrin and CCK, preservation of the stomach and the duodenal bulb appears to be a more physiologic reconstructive procedure than the standard PD. In addition the operation probably has more beneficial effect on the injured pancreas in time.
Prognostic value of serum creatinine and effect of treatment of hypertension on renal function. Results from the hypertension detection and follow-up program. The Hypertension Detection and Follow-up Program Cooperative Group. The Hypertension Detection and Follow-up Program followed up 10,940 persons for 5 years in a community-based, randomized, controlled trial of treatment for hypertension. Participants were randomized to one of two treatment groups, stepped care and referred care. The primary end point of the study was all-cause mortality, with morbid events involving the heart, brain, and kidney as secondary end points. Loss of renal function, ascertained by a change in serum creatinine, was among these secondary events. Baseline serum creatinine concentration had a significant prognostic value for 8-year mortality. For persons with a serum creatinine concentration greater than or equal to 1.7 mg/dl, 8-year mortality was more than three times that of all other participants. The estimated 5-year incidence of substantial decline in renal function was 21.7/1,000 in the stepped-care group and 24.6/1,000 in the referred-care group. Among persons with a baseline serum creatinine level between 1.5 and 1.7 mg/dl, the 5-year incidence of decline was 113.3/1,000 (stepped care) and 226.6/1,000 (referred care) (p less than 0.01). The incidence of decline in renal function was greater in men, blacks, and older adults, as well as in those with higher entry diastolic blood pressure. Among persons with a baseline serum creatinine level greater than or equal to 1.7 mg/dl, serum creatinine concentration declined by 25% or more in 28.6% of stepped-care and 25.2% of referred-care participants. Although the incidence of clinically significant hypercreatininemia in a hypertensive population is low, an elevated serum creatinine concentration is a very potent independent risk factor for mortality. The slightly lower rate of development of hypercreatininemia and the higher rate of improvement in stepped-care compared with referred-care participants is consistent with the belief that aggressive treatment of hypertension may reduce renal damage and the associated increased risk of death.
Integration of anticoagulation, thrombolysis and coronary angioplasty for unstable angina pectoris. Unstable angina pectoris remains a challenging acute ischemic syndrome to treat despite recent randomized trials that confirm the benefit of intravenous heparin. Coronary angioplasty, which is often required to treat the underlying arterial lesion, is adversely affected by the presence of thrombus with at least a 2-fold increase in abrupt closure. Four studies with heparin treatment prior to angioplasty indicate a reduction of abrupt vessel closure from 8-33% to 0-6% with apparent reduction of morbidity; no controlled trials are thus far available for heparin pretreatment. Another therapeutic alternative, thrombolytic therapy, has had quite equivocal results with several negative small studies. When angioplasty has been performed with thrombolytic therapy, a nonfibrin-specific plasminogen activator appears to be preferable. Newer studies that focus on thrombin inhibitors that bind to clot-bound thrombin and potent antiplatelet agents are in the early phase of clinical investigation. This review offers current recommendations for the integration of heparin, thrombolysis, and coronary angioplasty for unstable angina pectoris.
DNA flow cytometric evaluation of serous and mucinous cystic neoplasms of the pancreas. There have been few reports of flow cytometric studies of pancreatic neoplasms, whether endocrine or exocrine. In this report, the DNA content of three mucinous and seven serous cystic tumors of the pancreas was evaluated by flow cytometry on formaldehyde solution-fixed, paraffin-embedded tissue. Two serous cystadenomas were aneuploid, with the remaining five serous and all three mucinous being diploid. All cases had a low S phase (ranging from 0.1% to 3.1%), indicating neoplasms with a low turnover. From these results, it appeared that DNA flow cytometry as an independent factor did not discriminate between the benign pancreatic serous cystadenomas and the more aggressive mucinous cystic neoplasms.
Tumor vascularization: assessment with duplex sonography. In this prospective study, the authors examined 123 patients with benign or malignant neoplasms (breast cancer, n = 44; liver neoplasms, n = 43; and tumors affecting other organs, n = 36) to establish general criteria for evaluation of neoplastic lesions by means of duplex sonography. The frequency shifts determined by means of different Doppler frequencies (2.31 or 3.75 MHz) were converted into flow velocities. Only the highest systolic peak flow velocity obtained from a lesion was used for statistical evaluation. Receiver operating characteristic curves showed that a flow velocity of 0.4 m/sec is the optimal threshold value with which to differentiate benign from malignant tumors. The data obtained in all lesions indicated that only positive findings are potentially reliable. It is concluded that negative results of sonography should not be used to diagnose the presence of a benign lesion. The resistive index of the tumors was of negligible importance.
Deforming arthropathy complicating primary biliary cirrhosis. A 53-year-old woman with concurrent systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC) developed a deforming but minimally symptomatic arthropathy. The simultaneous occurrence of SLE and PBC is believed to be rare. Moreover, destructive arthritis, in the absence of serum rheumatoid factor, has not been previously reported with either disease. We review the association of liver disease with arthritis and propose a possible mechanism to account for the severe joint destruction seen in our patient.