shukoor65/lab-rag-model huggingface dataset:
Methanol poisoning. A rodent model with structural and functional evidence for retinal involvement. Methanol ingestion can lead to visual impairment, central nervous system dysfunction, or death. The extent of ocular involvement has been difficult to determine because the toxicity is restricted to humans and nonhuman primates due to species differences in methanol metabolism. A rodent model of methanol toxicity recently developed by us was used to evaluate retinal dysfunction in methanol poisoning. Formic acidemia and visual toxic reactions developed in methanol-intoxicated rats. Electroretinographic analysis indicated a significant early deficit in b-wave amplitude followed by a temporally delayed, lesser reduction in a-wave amplitude. Histologic evaluation of the eyes 60 hours after methanol administration revealed generalized retinal edema and vacuolation in the photoreceptors and retinal pigment epithelium. Ultrastructural examination showed swelling and disruption of the mitochondria in photoreceptor inner segments, optic nerve, and the retinal pigment epithelium. These studies document direct retinal involvement in this nonprimate model of methanol toxicity.
Dopa-responsive dystonia: long-term treatment response and prognosis. We report observations on the treatment of 66 patients with presumed dopa-responsive dystonia (DRD). Forty-seven of these patients had hereditary disease; 19 had disease of sporadic occurrence. Initial diagnostic confusion with "cerebral palsy" or "spastic diplegia" existed in 16 patients. Several patients benefited from anticholinergic medications and a few from carbamazepine. Levodopa was the most effective treatment in all cases. In the majority, there was an excellent response, with continued long-term clinical stability on levodopa therapy for as long as 10 to 22 years. Four men with sporadic disease and 1 woman with a sister affected with adolescent-onset parkinsonism had similar initial treatment response, but developed "wearing-off" and a less satisfactory response to levodopa within the first few years of treatment. This indicates that some patients with clinical syndromes suggestive of DRD may not have an excellent prognosis on long-term levodopa treatment and may represent misclassified cases of childhood-onset parkinsonism.
Characterization of estrogen receptor in human gastric cancer. Estrogen receptors (ER) were examined in cytosol, nuclear potassium chloride (KCl) extractable fraction, and nuclear KCl unextractable fraction by the dextran-coated charcoal adsorption method in various gastric cancer tissue. The overall ER-positive rate in the cytosol and nuclear fraction was 19.2%. The maximum binding site (Bmax) was 36.0 to 175.0 fmol/mg of protein, and the dissociation constant (Kd) was 0.6 to 1.6 X 10(-9) in cytosol fraction. In the nuclear fraction, Bmax was 7.5 fmol/mg of DNA and Kd was 2.3 X 10(-9). Estrogen receptors were characterized in cytosol protein. In cytosol, the estrogen (E2)-ER complex was sedimented at approximately the 5S and 8S regions by 5% to 20% linear sucrose gradient centrifugation. A steroid specificity study of ER showed the presence of an binder in gastric cancer tissue. In conclusion, these results that gastric cancer tissue has E2 binding sites with the same biochemical characteristics as in breast cancer and endometrial cancer strongly suggest the hormonal dependency of gastric cancer.
Anorectal varices--their frequency in cirrhotic and non-cirrhotic portal hypertension. Anorectal varices in portal hypertension have been little studied: Seventy eight per cent of 72 patients with portal hypertension had anorectal varices shown at flexible sigmoidoscopy. Significantly more patients with noncirrhotic portal hypertension had these varices than patients with cirrhosis (89% v 56%, p less than 0.01).
Jejunal biopsy in HIV-infected patients. Forty-nine HIV-infected patients were submitted to peroral jejunal biopsy in order to evaluate the presence of microorganisms and the histomorphometric aspects of the enteric mucosa with subsequent correlation of these findings to the appropriate clinical stage of the disease. Thirty-seven patients fulfilled the CDC criteria for AIDS, of whom 23 presented with diarrhea. Of the 12 patients who had not yet been given an AIDS diagnosis. 3 had persistent generalized lymphadenopathy and 9 were asymptomatic carriers. Flat mucosa was observed in two patients (8.7%) with diarrhea and coccidea. Subtotal villous atrophy and severe lamina propria (LP) mononuclear infiltrate (13%) were found only in patients with diarrhea. Moderate to severe histologic changes were more frequently observed in this group, not always related to the presence of microorganisms. Crypt hyperregeneration was a constant finding. Intraepithelial lymphocyte (IEL) count was decreased in patients with diarrhea. Specific infectious agents were unexpectedly rare for the tropical developing country population studied. The organism most commonly associated with diarrhea was Cryptosporidium sp. (21.7%). The etiology of diarrhea in a significant number of patients remains unclear.
Surgical management of retinal detachment associated with the acute retinal necrosis syndrome. We operated on nine eyes in eight patients with retinal detachment associated with acute retinal necrosis (ARN) syndrome. The patients were treated with scleral buckling, vitreoretinal surgery, or a combination of these treatments. Vitrectomised eyes underwent combinations of lensectomy, membrane dissection, scleral buckling, air-fluid exchange, endolaser photocoagulation, cryotherapy, and retinal tamponade with C3F8 gas or SF6 gas. Macular attachment was achieved in eight (89%) eyes. Vision improved in seven (78%) eyes, of which five (56%) achieved 20/200 or better vision. Three eyes that had received laser treatment posterior to areas of retinitis suffered retinal detachment despite this prophylactic treatment. Poor visual outcome resulted from viral infection of the optic nerve or macular involvement, macular hole formation, macular pucker, or hypotony.
Differences in the use of procedures between women and men hospitalized for coronary heart disease BACKGROUND AND METHODS. Previous studies at individual hospitals have reported differences in the use of major diagnostic and therapeutic procedures for women and men with coronary heart disease. To assess whether these differences can be generalized, we performed retrospective analyses of coronary angiography and revascularization (coronary-artery bypass surgery or percutaneous transluminal coronary angioplasty) in women and men hospitalized for coronary heart disease in 1987, using abstract data on 49,623 discharges in Massachusetts and 33,159 discharges in Maryland. We used multiple logistic regression to estimate the adjusted odds of the use of a procedure, controlling for principal diagnosis, age, secondary diagnosis of congestive heart failure or diabetes mellitus, race, and insurance status. RESULTS. The adjusted odds of undergoing angiography were 28 percent and 15 percent higher for men than for women in Massachusetts and Maryland, respectively (95 percent confidence intervals for the odds ratios, 1.22 to 1.35 and 1.08 to 1.22). The respective adjusted odds of undergoing revascularization were 45 percent and 27 percent higher for men than for women (95 percent confidence intervals, 1.35 to 1.55 and 1.16 to 1.40). Because these differences could be related to differing thresholds for hospital admission, we performed a second analysis limited to patients with diagnosed acute myocardial infarction (11,865 discharges in Massachusetts and 6894 discharges in Maryland), a group in which all patients would be expected to receive hospital care. The male-to-female odds ratios in both states remained similar in magnitude and were statistically significant for angiography and revascularization. CONCLUSIONS. These findings demonstrate that women who are hospitalized for coronary heart disease undergo fewer major diagnostic and therapeutic procedures than men. These differences may represent appropriate levels of care for men and women, but it is also possible that they reflect underuse in women or overuse in men. Further study should assess the cause of these differences and their effect on patients' outcomes.
Anterolateral transthoracic transvertebral resection of an intramedullary spinal arteriovenous malformation. Case report. The case is reported of a 16-year-old girl with an anterior thoracic spinal cord arteriovenous malformation (AVM) who presented with subarachnoid hemorrhage and sudden change in lower-extremity strength. Spinal angiography revealed a Type II (glomus) intramedullary AVM at the T7-8 level fed by multiple branches of the anterior spinal artery. The AVM was successfully resected using an anterolateral transthoracic approach. The details of this approach and its use for surgery of anterior thoracic spine lesions are described.
Fucosyltransferases: differential plasma and tissue alterations in hepatocellular carcinoma and cirrhosis. To determine whether abnormal metabolism of L-fucose in hepatocellular carcinoma is accompanied by alterations in the activities of fucosyltransferases, the latter were determined in plasma and liver tissue of patients with this disease and in cirrhotic and normal subjects. Activities of alpha-2/alpha-3 and alpha-6-L-fucosyltransferases were all significantly greater in plasma from patients with hepatocellular carcinoma than in plasma from cirrhotic patients or normal subjects (p less than 0.025). The activity of each enzyme was dependent, to a similar extent, on Mn2+, Mg2+ and triton X-10, irrespective of the source, and all displayed pH optimums in the range of 7.5 to 8.0. In contrast, activities of alpha-2/alpha-3 fucosyltransferases were significantly lower (p less than 0.025) in homogenates prepared from tumorous liver tissue than in that prepared from nontumorous tissue from hepatocellular carcinoma and cirrhotic patients, whereas for the alpha-6 enzyme the situation was reversed (typically, tumor tissue levels were 5 pmol/hr/mg; in nontumor tissue they were 2 pmol/hr/mg). Activities of galactosyl and mannosyltransferase in tumor tissue were greater in all cases than in nontumor cirrhotic tissue. Plasma fucosyltransferases are specifically elevated in hepatocellular carcinoma but different mechanisms appear to underlie the changes seen for alpha-2/alpha-3 and alpha-6-L-fucosyltransferases.
A carbon fiber implant to aid interbody lumbar fusion. Mechanical testing. A carbon-fiber-reinforced polymer implant has been designed to aid interbody lumbar fusion. The cage-like implant has ridges or teeth to resist pullout or retropulsion, struts to support weight bearing, and a hollow center for packing of autologous bone graft. Because carbon is radiolucent, bony healing can be imaged by standard radiographic techniques. The device has been mechanically tested in cadaver spines and compared with posterior lumbar interbody fusion performed with donor bone. The carbon device required a pullout force of 353 N compared with 126 N for donor bone. In compression testing, posterior lumbar interbody fusion performed with the carbon device bore a load of 5,288 N before failure of the vertebral bone. Posterior lumbar interbody fusion performed with donor bone failed at 4,628 N, and unmodified motion segments failed at 6,043 N. The carbon fiber implant separates the mechanical and biologic functions of posterior lumbar interbody fusion.
Necrotizing tracheitis caused by Corynebacterium pseudodiphtheriticum: unique case and review. The occasional pathogenicity of nondiphtheria corynebacteria in both immunocompetent and immunocompromised individuals is now well established. Previously described sites of infection include heart valves, wounds, urinary tract, and lungs. This report of necrotizing tracheitis caused by Corynebacterium pseudodiphtheriticum illustrates the widening spectrum of infections caused by these organisms. A 54-year-old man developed respiratory distress and symptoms of upper airway obstruction unresponsive to inhaled bronchodilators, systemic corticosteroids, or intravenous erythromycin. A spirometry flow-volume loop demonstrated fixed upper airway obstruction. Fiberoptic bronchoscopic examination revealed a circumferential inflammatory process partially occluding the tracheal lumen. Gram staining revealed gram-positive rods typical of corynebacteria, and cultures of tracheal tissue yielded C. pseudodiphtheriticum resistant to erythromycin and clindamycin. There was no clinical or laboratory evidence for exotoxin or cell-associated toxins. Treatment with intravenous penicillin resulted in resolution of the inflammatory process and eradication of the organisms, as assessed by subsequent cultures.
Same-day angioplasty and diagnostic catheterization: safe and effective but riskier in unstable angina. Percutaneous transluminal coronary angioplasty was performed at the time of the diagnostic catheterization in 188 patients (215 lesions) at a University Hospital in order to assess the efficacy of this approach and the potential role it should play in the evaluation and treatment of patients. Patients either presented for diagnostic catheterization for evaluation of stable coronary disease (79 patients) or for unstable or new onset anginal symptoms (109 patients). Lesions were graded as to whether they were simple or complex; and post angioplasty films were reviewed for success rate, and degree of revascularization. Patients who were referred for stable anginal symptoms had a slightly higher success rate (91%) compared to those who were referred for new onset or more unstable symptomatology (85%, p = ns). Additionally, lesions morphology was judged to be more complex in unstable patients, as 67% had complex lesions with the presence of thrombus or ulcerated plaque in 56% of these stenoses. Angioplasty success was high for simple lesions in all patients, but was most unfavorable for complex stenoses in patients who presented with unstable symptoms (81% success rate). In patients who presented with new onset or unstable symptoms multivessel disease was present in 69% and angioplasty was more often geared at dilating a culprit stenosis leaving only 49% of these patients with complete revascularization. On the other hand, in 76% of those patients who presented with stable angina complete revascularization was a common outcome. Length of hospital stay was considerably shorter at 2.9 +/- 0.8 days in those patients who presented with stable symptoms.
Neurohumoral activation in congestive heart failure. This article reviews the evidence that congestive heart failure is accompanied by an increased plasma norepinephrine concentration and that this is due not only to a reduced tissue clearance of the substance but also to a marked increase in sympathetic nerve activity. It also reports data that indicate that the sympathetic activation is associated with an activation of the renin-angiotensin system and an increased plasma level of vasopressin. At which degree of congestive heart failure these phenomena become manifest is not clear, but some studies suggest that the sympathetic and renin-angiotensin systems may be normal in asymptomatic congestive heart failure but already somewhat activated when this condition reaches New York Heart Association class II. There is also evidence that this activation, though initially compensatory, is eventually responsible for a number of adverse cardiovascular effects that account for the negative relationship between this event and survival. Finally, the article discusses the inability of the increased plasma level of atrial natriuretic peptide that characterizes congestive heart failure to offset the adverse effects of the neurohumoral activation and the variable influence of drug treatment on this phenomenon. This is not impossible to achieve, however, because heart transplantation appears to rapidly normalize a major factor in the increased sympathetic activity observed before surgical intervention, that is, impairment of the arterial baroreflex.
Early Treatment Diabetic Retinopathy Study design and baseline patient characteristics. ETDRS report number 7. The Early Treatment Diabetic Retinopathy Study (ETDRS), a multicenter collaborative clinical trial supported by the National Eye Institute, was designed to assess whether argon laser photocoagulation or aspirin treatment can reduce the risk of visual loss or slow the progression of diabetic retinopathy in patients with mild-to-severe nonproliferative or early proliferative diabetic retinopathy. The 3711 patients enrolled in the ETDRS were assigned randomly to either aspirin (650 mg per day) or placebo. One eye of each patient was assigned randomly to early argon laser photocoagulation and the other to deferral of photocoagulation. Both eyes were to be examined at least every 4 months and photocoagulation was to be initiated in eyes assigned to deferral as soon as high-risk proliferative retinopathy was detected. Examination of a large number of baseline ocular and patient characteristics indicated that there were no important differences between randomized treatment groups at baseline.
Clinical efficacy of sucralfate in the treatment of gastric ulcer. We performed a randomized, single-blind study in Japan to investigate the efficacy and safety of two dosage regimens of sucralfate granules, 2 g, twice daily (b.i.d. group, n = 30) and 1 g, 4 times daily (q.i.d. group, n = 27), on ulcer healing in 57 patients with endoscopically proven gastric ulcer. Endoscopy was performed after 4 weeks and, if complete healing was not achieved, again after an additional 4 weeks. Of 57 patients, 11 were excluded from the statistical analysis because of protocol violation (six in b.i.d. group, five in q.i.d. group). Of 46 patients eligible for the analysis of healing rates, four patients in the b.i.d. group (all at 8 weeks) and five patients in the q.i.d. group (two at 4 weeks and three at 8 weeks) were withdrawn due to patients' inconvenience. As the possibility that the withdrawals were due to the treatment failures could not be denied, we used the Kaplan-Meier method and generalized Wilcoxon test/logrank test for the calculation and evaluation of healing rates in this study, respectively. Healing rates at 4 and 8 weeks were 50% and 94% in the b.i.d. group and 35% and 68% in the q.i.d. group. There was no significant difference in healing rates between the groups. No serious adverse effect was observed in either group. These results suggest that the 2 g b.i.d. dose of sucralfate in granule form is at least as effective as the conventional dose of 1 g q.i.d. in the treatment of active gastric ulcers and could lead to better patient compliance.
Vasospasm in a coronary artery aneurysm. Coronary artery aneurysms are not believed to have enough intact smooth muscle to generate significant vasoconstriction. A case is presented illustrating vasospasm of a large fusiform aneurysm of a right coronary artery during angioplasty. Pathophysiology of aneurysms is discussed.
Difficult pediatric diagnoses. Bruising and bleeding [published erratum appears in Pediatr Clin North Am 1991 Oct;38(5):viii] An approach to the evaluation of a child who presents to the pediatrician with bruising is outlined. Important clues in the history and physical examination that suggest disorders of platelet number and function or coagulation abnormalities are presented. A scheme for using screening tests of coagulation and platelet function is followed by a brief summary of currently available therapies appropriate for bleeding episodes in children.
Clinical and financial audit of diagnostic protocols for lesions of the cerebellopontine angle OBJECTIVE--To assess the diagnostic efficiency and costs of protocols used for investigating patients with suspected lesions of the cerebellopontine angle. DESIGN--Prospective evaluation of tests of auditory brain stem responses and acoustic reflex thresholds, electronystagmography, and calorics. Positive test results were confirmed or refuted by high resolution computed tomography with intravenous enhancement. SETTING--Single general otolaryngology clinic in a teaching hospital. PATIENTS--270 consecutive patients with sensorineural hearing loss requiring investigation to exclude a lesion of the cerebellopontine angle. MAIN OUTCOME MEASURES--Estimated costs of various diagnostic protocols and performance in detecting tumours of the cerebellopontine angle. RESULTS--Protocols including tests of auditory brain stem responses and acoustic reflex thresholds as sifting tests before computed tomography were clinically acceptable and presented considerable savings over the use of computed tomography in all patients (74,000 pounds or 84,000 pounds v 122,000 pounds). The use of electronystagmography and calorics could not be justified on clinical or financial grounds. CONCLUSIONS--Audiological tests of auditory brain stem responses and acoustic reflex thresholds followed by computed tomography constitute the most cost effective protocol for determining suspected lesions of the cerebellopontine angle. IMPLICATIONS--The cost effectiveness of diagnostic protocols should be evaluated throughout the health service.
The treatment of ankle valgus by surface epiphysiodesis. Progressive ankle valgus in childhood requiring surgical correction is usually because of paralytic disease or conditions that produce a short distal fibula such as multiple exostoses or both. Surface epiphysiodesis of the distal medial tibial physis was used to correct valgus deformity in ten ankles in seven patients. This procedure has been found to be a simple and effective method of treatment. Measurement of the degree of valgus and calculation of the remaining growth of the distal tibial physis are recommended to determine whether this procedure will be effective. It is most often indicated in the presence of moderate valgus in children aged 11 to 14 years.
Uvulopalatopharyngoplasty in obstructive apnea. Value of preoperative localization of site of upper airway narrowing during sleep. We hypothesized that those obstructive sleep apnea (OSA) patients with upper airway collapse during sleep within the transpalatal airway would have a more favorable response to uvulopalatopharyngoplasty (UPP) than those patients with obstruction within the hypopharyngeal airway. We tested this hypothesis in seven OSA patients with transpalatal and seven with hypopharyngeal obstruction undergoing UPP. Preoperatively the apnea/hypopnea index (AHI) was different between palatal and hypopharyngeal obstructors, 37.8 +/- 6.0 (+/- SEM) and 63.9 +/- 6.3, respectively (p less than 0.05), but the apnea-associated arterial oxygen desaturation and the lowest sleep saturation level were not different between the two groups. Postoperatively the AHI was 17.6 +/- 7.2 in the palatal obstructors and 40.3 +/- 15.6 in the hypopharyngeal obstructors (both p less than 0.05 from preoperative AHI). The palatal obstructors had a significant decrease in the percentage of sleep time spent apneic and the hypopharyngeal obstructors had a significant decrease in the hypopnea, but not apnea, time following surgery. The palatal obstructors had a significantly higher postoperative arterial oxygen saturation than the hypopharyngeal obstructors. Two hypopharyngeal obstructors worsened postoperatively. In addition we found that regardless of the site of the obstruction preoperatively, all obstructions occurred at the level of the palate postoperatively. We conclude that patients with preoperative transpalatal obstruction had diminution in obstructive apneas and those with hypopharyngeal obstruction had diminution in hypopneas but not apneas. Oxygenation was better postoperatively in the palatal obstructors, and none worsened postoperatively. These results suggest that identification of the site of upper airway obstruction in OSA may be beneficial.