shukoor65/lab-rag-model huggingface dataset:
The analgesic effects of caffeine in headache. Caffeine is frequently added to mild analgesic preparations but its effect when used alone on pain has never been studied in humans. Using a double-blind placebo-controlled multiple crossover design, 53 patients with non-migrainous headaches were given placebo, acetaminophen, 2 doses of caffeine and 2 combinations of caffeine with acetaminophen. Caffeine appeared to have independent analgesic effects that were equivalent to acetaminophen and were still significant when statistical adjustments were made for prior caffeine consumption and caffeine's effects on mood.
Molecular biology of prion diseases. Prions cause transmissible and genetic neurodegenerative diseases, including scrapie and bovine spongiform encephalopathy of animals and Creutzfeldt-Jakob and Gerstmann-Straussler-Scheinker diseases of humans. Infectious prion particles are composed largely, if not entirely, of an abnormal isoform of the prion protein, which is encoded by a chromosomal gene. A posttranslational process, as yet unidentified, converts the cellular prion protein into an abnormal isoform. Scrapie incubation times, neuropathology, and prion synthesis in transgenic mice are controlled by the prion protein gene. Point mutations in the prion protein genes of animals and humans are genetically linked to development of neuro-degeneration. Transgenic mice expressing mutant prion proteins spontaneously develop neurologic dysfunction and spongiform neuropathology. Understanding prion diseases may advance investigations of other neurodegenerative disorders and of the processes by which neurons differentiate, function for decades, and then grow senescent.
Anterior transpetrosal-transtentorial approach for sphenopetroclival meningiomas: surgical method and results in 10 patients. This report presents a new surgical method and the results in 10 patients with petroclival meningiomas extending into the parasellar region (sphenopetroclival meningiomas). Minimal but effective extradural resection of the anterior petrous bone via a middle fossa craniotomy offered a direct view of the clival area with preservation of the temporal bridging veins and cochlear organs. The dural incision was extended anteriorly to Meckel's cave, and in cases with invasion of the cavernous sinus, Parkinson's triangle was enlarged by mobilization of the trigeminal nerve. This approach offered an excellent view from the mid-clivus to the cavernous sinus. Extra-as well as intradural tumor masses and dural attachments could be cleared under direct view of the pontine surface. The risk of injury to the lower cranial nerve and of retraction damage to the temporal lobe and brain stem were kept minimal by this approach. Total tumor resection was achieved in 7 patients, with no resultant mortality. Eight patients had a satisfactory postsurgical course, extraocular paresis being their main complaint. The extent of tumor resection depended on the degree of tumor adhesion to the carotid artery, and operative morbidity on the degree of tumor invasion of the brain stem. Of the 3 patients in whom subtotal tumor removal was achieved, only one experienced regrowth of the tumor and underwent a second operation during the follow-up period (6 months-6 years).
Native right atrial tamponade with the Jarvik total artificial heart. Following a massive myocardial infarction culminating in cardiogenic shock, a 61-year-old man underwent implantation of the Jarvik 70-ml total artificial heart. On the fifth postoperative day, hemodynamic instability coupled with subtle radiographic changes and impaired mechanical right ventricular diastolic inflow were instrumental in establishing the diagnosis of localized native right atrial tamponade. To our knowledge, this report is the first detailed discussion of this phenomenon.
High density lipoprotein turnover in patients with hypertension. Although hyperinsulinemia and decreased high density lipoprotein cholesterol concentration can occur in patients with hypertension, there is no information available concerning the dynamic state of high density lipoprotein metabolism. To address this issue, we quantified high density lipoprotein turnover in 12 patients with mild hypertension and 11 matched subjects with normal blood pressure. Patients with high blood pressure had lower high density lipoprotein cholesterol concentrations. Fractional catabolic rates of 125I-apolipoprotein AI (apoAI)/high density lipoprotein were faster in patients with hypertension (0.36 +/- 0.02 versus 0.26 +/- 0.02 l/day, p less than 0.001). Total synthetic rates of apoAI were also significantly greater in patients with high blood pressure (17.4 +/- 1.1 versus 13.2 +/- 0.6 mg/kg/day, p less than 0.001). Although significant correlation was observed between blood pressure and fractional catabolic rate of 125I-apoAI/high density lipoprotein in the experimental population (r = 0.52, p less than 0.01), no relation was found when patients with normal blood pressure or hypertension were considered separately. However, a highly significant positive correlation was found between 125I-apoAI/high density lipoprotein fractional catabolic rate and insulin concentration in the entire population (r = 0.72, p less than 0.001). In conclusion, the patients with mild hypertension studied were hyperinsulinemic, had a faster fractional catabolic rate of 125I-apoAI/high density lipoprotein, and a lower high density lipoprotein-cholesterol concentration. It is suggested that the changes seen in high density lipoprotein-cholesterol concentration and 125I-apoAI/high density lipoprotein fractional catabolic rates were secondary to the hyperinsulinemia and not due to the high blood pressure per se.
Cold-induced brain edema and infarction are reduced in transgenic mice overexpressing CuZn-superoxide dismutase. It has been proposed that oxygen-derived radicals, superoxide in particular, are involved in the alteration of blood-brain barrier permeability and the pathogenesis of brain edema following trauma, ischemia, and reperfusion injury. Using transgenic mice that overexpress the human gene for copper-zinc-superoxide dismutase, we studied the role of superoxide radicals in the blood-brain permeability changes, edema development, and delayed infarction resulting from cold-trauma brain injury. At 2 hours after a 30-second cold injury, cerebral water and Evans blue contents were reduced, respectively, from 80 +/- 0.2% and 132.7 +/- 12.9 micrograms/gm of dry weight for nontransgenic mice to 78.5 +/- 0.3% and 87.1 +/- 9.9 micrograms/gm of dry weight for transgenic mice. Infarction, as measured by 2,3,5-triphenyltetrazolium chloride staining, was reduced by 52% in transgenic brains. These data indicate that an increased level of superoxide dismutase activity in the brain reduces the development of vasogenic brain edema and infarction. Superoxide radicals play an important role in the pathogenesis of these lesions in cold-traumatized brain.
Technical considerations for prophylactic mastectomy in patients at high risk for breast cancer. A study of 5 patients and 10 mastectomy specimens was performed to identify the extent of surgery necessary to completely remove all breast tissue in patients having prophylactic mastectomies. A standard total mastectomy performed for breast cancer was shown to frequently leave breast tissue within the superficial pectoralis major muscle and the lower skin flap. Frozen section analysis of margins was found to be essential to clear the axillary extension of the breast and lower skin flap in particular. The value of more extensive surgery to remove all glandular elements of the breast in the high-risk patient remains to be demonstrated.
Automated procedure for dewaxing and rehydration of paraffin-embedded tissue sections for DNA flow cytometric analysis of breast tumors. Flow cytometric DNA analysis of paraffin-embedded tumors is an important diagnostic and prognostic tool in clinical pathology. The technique is limited, however, by the time-consuming multistep procedure for dewaxing and rehydrating tissue. The authors developed an automated procedure to complete the dewaxing and rehydration of tissue using a routine histologic tissue processor with a 24-hour timer. This technique provided excellent tissue recovery and reproducible DNA histograms comparable to those obtained by manual methods. Subsequently, the authors analyzed the DNA content of 93 paraffin-embedded breast cancer tissues. The automation of a significant portion of the routine processing required for paraffin-embedded tissue makes cytometric DNA analysis a more practical procedure in the laboratory.
Late complications involving the ascending aorta after cardiac surgery: recognition and management. Pseudoaneurysms and dissecting aneurysms of the ascending aorta after cardiac surgery are uncommon but important complications. Pseudoaneurysms, which result from extravasation of blood into the mediastinum, most commonly occur at the site of aortotomy or aortic cannulation. Infection may play an important role. Dissecting aneurysms after cardiac surgery usually occur at the site of aortic incision or cross clamping, especially in atherosclerotic aortas. Both conditions may be clinically silent but more frequently are seen with significant symptoms. Noninvasive techniques including CT scan, MRI, and echocardiography are very useful in the diagnosis of both complications, with contrast aortography remaining the definitive method. Surgical repair is necessary for dissecting aneurysms and for enlarging and symptomatic pseudoaneurysms, with improving morbidity and mortality.
Nutritional aspects and swallowing function of patients with Parkinson's disease. Seven patients with Parkinson's disease and three patients with progressive supranuclear palsy underwent adrenal medullary transplant to the caudate nucleus for treatment of their neurologic disease. Preoperative nutritional assessment demonstrated that a significant number of the Parkinson's patients had mild to moderate nutritional depletion. Motility problems, manifest by dysphagia and delayed gastric emptying causing problems over a number of years, were probably responsible. Of the 10 patients studied, 6 were studied by videofluoroscopy. All patients had variable dysphagia of variable servility with or without aspiration. Etiologic factors included the basic underlying neurologic disease, delay in resumption of anti-parkinsonian medications, use of metoclopramide, and postoperative medical complications leading to a debilitated clinical state.
Acute basophilic leukemia. A clinical, morphologic, and cytogenetic study of eight cases. The authors describe eight cases of acute basophilic leukemia. In six of the eight cases, basophilic involvement was not apparent by light microscopic examination. The cases were identified on the basis of ultrastructural evidence for basophil/mast cell differentiation of the blasts with little or no differentiation into other lineages. Ultrastructural analysis revealed immature basophil granules in blasts in all eight cases and theta granules in blasts in four cases. In three cases, ultrastructural evidence of mast cell differentiation also was present, with rare cells showing evidence for both basophil and mast cell differentiation. No clinical features distinguished this group of patients from others with acute myeloid leukemia. Cytogenetically, the cases were heterogeneous. Three had a Philadelphia chromosome; none had a t(6;9). The authors conclude that ultrastructural analysis usually must be used to diagnose acute basophilic leukemia, that acute basophilic leukemia is associated frequently with the Philadelphia chromosome, and that the ultrastructural findings provide evidence for a common origin of basophils and mast cells.
Autoimmune enteropathy and nephropathy with circulating anti-epithelial cell antibodies. We describe a child with circulating anti-epithelial cell antibodies, autoimmune enteropathy with intestinal villous atrophy, and membranous glomerulonephritis. The patient had persistent diarrhea at 6 months of age, and a small bowel biopsy showed active enteritis, villous atrophy, and crypt hyperplasia. When the patient was, 10 months of age, nephrotic syndrome developed because of membranous glomerulonephritis. Results of tests for circulating immune complexes were negative. Indirect immunofluorescence studies revealed a circulating antibody directed against renal epithelial cells. Circulating antibodies directed against normal small intestine epithelial cells were also detected by the immunoperoxidase technique. Western blot and immunoprecipitation identified a 55-kd antigen, in both small bowel and kidney, that reacted with an antibody in the patient's serum. High-dose prednisone therapy induced a clinical remission, resolution of the small bowel injury, and diminished serum anti-epithelial cell antibodies; after dose reduction, clinical relapse occurred with villous atrophy and reappearance of anti-epithelial cell antibodies. When the patient was 45 months of age, persistent diarrhea recurred despite intravenous administration of corticosteroids, cyclosporine, and total parenteral nutrition. Autoantibodies to a 55-kd epithelial cell protein are temporally related to the development of enteropathy and nephropathy. Study of similar patients is needed to determine the role of such antibodies in this disorder.
Burning pain in an extremity. Breaking the destructive cycle of reflex sympathetic dystrophy. The pathogenesis of reflex sympathetic dystrophy is controversial, but the condition can result from a major or seemingly minor injury to a limb, or even an insult to an organ, such as stroke or myocardial infarction. Onset can be sudden or insidious. The syndrome is characterized primarily by localized, deep, burning pain in a limb--pain that may not follow any logical distribution. Nonpitting edema, skin hyperesthesia, and guarding of the limb usually accompany the pain. If treatment is not instituted, deformity, contracture, and wasting of the limb can eventually occur. With appropriate therapy, the process can be stopped and often reversed. The keys are a high index of suspicion, early diagnosis, and aggressive treatment.
Effects of nitroglycerin and diltiazem on well-developed coronary collateral circulation in conscious dogs. The purpose of the present study was to compare the effects of nitroglycerin and diltiazem on coronary collateral circulation. Studies were conducted in 8 conscious dogs instrumented for the measurement of left circumflex coronary artery (LCCA) flow, subendocardial segment lengths in areas perfused by the LCCA, and left anterior descending coronary artery (LAD). Brief, repeated LCCA occlusions sufficiently developed collateral vessels for the resting metabolic requirement in the LCCA region. One week following the cessation of repeated LCCA occlusions, two-minute coronary occlusions with and without drug pretreatment were performed on separate days. The ischemic responses to coronary occlusions were not altered by diltiazem (50 micrograms/kg, IV), but nitroglycerin (5 micrograms/kg, IV) attenuated myocardial ischemia definitely. The authors conclude that nitroglycerin produces greater effects than diltiazem in attenuating myocardial ischemia in the collateral dependent zone when effects of each drug on systemic and coronary circulation were minimized by pretreatment with small doses.
Comparative evaluation of carcinoembryonic antigen, secretory component, and mucins in index and metachronous adenomas of the colorectum. Of 124 patients who underwent endoscopic polypectomy, 70 were colonoscopically reevaluated during a mean period of 10 years. On the basis of the clinical outcome, the patients were divided into three groups: group 1, 31 patients who had a colon still with no adenomas or cancer; group 2, 35 patients in whom one or more metachronous adenomatous polyps developed; and group 3, 4 patients in whom a carcinoma of the colon subsequently developed. In addition to the clinical and pathological features, the pattern of the immunohistologic staining for carcinoembryonic antigen and secretory component was studied. Moreover, the mucin histochemical staining intensity of neutral mucins, sulfomucins, and sialomucins was evaluated. The features of the 40 index adenomas obtained from patients in group 1 were compared with the features of the 51 index adenomas from patients in group 2. Furthermore, these characteristics of the index adenomas were compared with those in the 69 metachronous adenomas of the group 2 patients. It was found that male sex (P less than 0.005) and a history of colorectal neoplasia (P less than 0.02) are main factors for the development of new adenomas. The neutral mucins were less abundant in the group 2 index adenomas (r = -0.21; P less than 0.05). The expression of the other evaluated markers was not significantly different between both groups, although the group 2 index adenomas were significantly smaller (r = -0.22; P less than 0.05) and showed a trend toward a more pronounced cytoplasmic expression of carcinoembryonic antigen than the index adenomas from group 1 (22% vs. 12.5%). Moreover, it was found that in comparison with the index adenomas, metachronous adenomas were significantly smaller (r = -0.24; P less than 0.01) and more sessile (r = 0.20; P less than 0.002). Significant negative correlations, i.e., decrease, were also found in the expression of carcinoembryonic antigen (surface P less than 0.001; cytoplasmic P less than 0.05) and neutral mucins (P less than 0.005) between the index adenomas and the metachronous adenomas, whereas positive correlations were found for secretory component (P = 0.0001) and sulfomucins (P less than 0.05). These findings suggest that a limited production of neutral mucins in the goblet cells of a small index adenoma from a male patient with a history of colorectal neoplasia is indicative of an increased risk for the development of new colorectal adenomas. Furthermore, the clinical, mucin histochemical, and immunohistochemical findings of the metachronous adenomas show less malignancy-associated features than those of the index adenomas.
Comparison of enteral nutrition and drug treatment in active Crohn's disease. Results of the European Cooperative Crohn's Disease Study. IV This study compared the effect of enteral nutrition as the sole therapy of active Crohn's disease with drug treatment. Patients with active Crohn's disease (Crohn's Disease Activity Index greater than 200) were randomized to receive either enteral nutrition with a liquid oligopeptide diet (n = 55) or a combination of 6-methylprednisolone, 48 mg daily, subsequently tapered, and sulfasalazine, 3 g daily (n = 52). The two groups were not different with respect to age, sex, body weight, location of disease, or treatment before the study. The severity of disease was similar at the beginning of the study in both groups [Crohn's Disease Activity Index (mean +/- SEM), 323 +/- 12 vs. 316 +/- 11]. Remission was defined as a decrease of the initial Crohn's Disease Activity Index by 40% or at least 100 points. Twenty-nine patients in the diet group and 41 patients in the drug group reached remission within 6 weeks of therapy (chi 2 test, P less than 0.01). The median elapsed time to remission was 30.7 days in the diet group compared with 8.2 days in the drug group (Mantel Cox, P less than 0.01). To determine whether one of these treatments was more beneficial for a subgroup of patients, the effectiveness of both treatments was analyzed separately in patients with very severe disease (initial Crohn's Disease Activity Index greater than 300) and less severe disease (initial Crohn's Disease Activity Index less than 300), and in patients with different disease location. However, no influence of initial disease activity or disease location on the effect of either treatment could be shown. These data show that enteral nutrition is less effective than a combination of 6-methylprednisolone and sulfasalazine in treating active Crohn's disease.
Abnormalities of pathways of fibrin turnover in the human pleural space. The potential importance of pleural fibrin deposition in the pathogenesis of pleural injury is supported by both clinical and experimental observations. We hypothesized that the local equilibrium between procoagulant and fibrinolytic activities is disrupted to favor fibrin deposition in exudative pleuritis. To test this hypothesis, we characterized procoagulant and fibrinolytic activities in pleural exudates from patients with pneumonia, lung cancer, or empyema and transudates from patients with congestive heart failure. Procoagulant activity was generally increased in exudative processes and was due mainly to tissue factor. All effusions contained antithrombin III and inhibited factor Xa and thrombin, but endogenous prothrombinase or thrombin activities were variably detected. Pleural fluid fibrinolytic activity was increased in congestive heart failure and was due to both tissue plasminogen activator and urokinase. Depressed fibrinolytic activity was found in pleural exudates despite increased concentrations of plasminogen, mainly glu-1-plasminogen, and was due to inhibition of plasminogen activation by plasminogen activator inhibitors 1 and 2 and of plasmin, in part by alpha 2-antiplasmin. Concentrations of PAI-1 in exudative pleural fluids were increased up to 913-fold, compared with normal pooled plasma. Exudative pleural effusions are characterized by increased procoagulant and depressed fibrinolytic activity, favoring fibrin deposition in the pleural space. The balance of these activities is reversed and favors fibrin clearance in congestive heart failure.
Adenine arabinoside monophosphate and acyclovir monophosphate coupled to lactosaminated albumin reduce woodchuck hepatitis virus viremia at doses lower than do the unconjugated drugs. The woodchuck was selected to study the efficacy of liver-targeted antiviral drugs on hepadnavirus replication. Nineteen woodchucks chronically infected with woodchuck hepatitis virus were treated with adenine arabinoside monophosphate or acyclovir monophosphate, either free or conjugated with the liver-targeting molecule lactosaminated human serum albumin. Circulating woodchuck hepatitis virus DNA levels remained unchanged in untreated animals and in those receiving the carrier lactosaminated human serum albumin alone; in contrast, they were consistently lower after 5 days of treatment with the antiviral drugs. Free and conjugated adenine arabinoside monophosphate were active at doses of 10 and 0.75 mg/kg, respectively, and free and coupled ACVMP were active at doses of 20 and 2.6 mg/kg, respectively. These results indicate that the dosages of adenine arabinoside monophosphate and acyclovir monophosphate required to inhibit hepadnavirus growth can be sharply reduced by coupling the drugs to lactosaminated human serum albumin.
Chronic calcific pancreatitis in a patient with Waldenstrom's macroglobulinemia. We report on a patient with chronic calcific pancreatitis associated with Waldenstrom's macroglobulinemia, and we have hypothesized a possible relationship between these two entities. The hyperviscosity of serum in Waldenstrom's macroglobulinemia may be associated with a viscous pancreatic juice that leads to stone formation.
Comparative aspects of osteosarcoma. Dog versus man. Canine osteosarcoma bears striking resemblance to osteosarcoma in humans. Similarities include the following: male sex predilection, large patient size, 75% or more affecting the appendicular site, metaphyseal location, generally unknown etiology, less than 10% of patients have documented metastasis at presentation, over 90% of tumors show high-grade histology, 75% of tumors show aneuploidy, the metastatic rate is 80% or more with amputation alone, the lung is the most common site of metastasis, and there is improved survival with adjuvant chemotherapy. The major differences are age of onset, with dogs being affected in middle age; greater frequency in the dog, with over 8000 new cases per year; and time to metastasis being faster in the dog than man. Canine osteosarcoma is a readily available and highly comparable spontaneously occurring cancer that should be useful in a better understanding of the same disease in humans.