123rc/medical_text huggingface dataset:
The Merkel cell and associated neoplasms in the eyelids and periocular region. Merkel cells are clear oval cells in the epidermis and outer root sheaths of hair follicles, which are probably of epithelial origin, share ultrastructural features with neuroendocrine cells, and are found in association with touch receptors. In the eyelid, they occur singly in the epidermis and external root sheaths of hairs and eyelashes, and in specialized touch spots alternating with eyelashes. Their typical electron microscopical and antigenic features include dense-core granules, intranuclear rodlets, spinous processes, and a positive reaction for specific cytokeratins, epithelial membrane antigen, neuron-specific enolase, chromogranin and synaptophysin. Merkel cell carcinoma probably develops from precursor cells which give rise to keratinocytes and Merkel cells, and nearly one out of ten Merkel cell carcinomas occur in the eyelid and periocular region. They tend to be bulging lesions near the lid margin of elderly patients, reddish in color, and erythematous with telangiectatic vessels. The diagnosis is based on the frequent presence of neurofilaments and paranuclear aggregates of intermediate filaments in addition to features typical of normal Merkel cells. The tumor often mimics lymphoma or undifferentiated carcinoma and frequently invades lymphatic vessels. One third of Merkel cell carcinomas recur, almost two thirds give rise to regional node metastases, and up to one half metastasize widely and result in death. Initial treatment should be prompt and aggressive, with wide resection and routine postoperative irradiation. Although metastatic lesions often respond to radiation therapy and cytostatic drugs, these treatments are mainly of palliative value.
Chronic musculoskeletal pain and depressive symptoms in the general population. An analysis of the 1st National Health and Nutrition Examination Survey data. Chronic pain and depression frequently occur together. A selection bias afflicts all hospital clinic and family practice populations in which this relationship has been examined. We report here some of the results from civilian populations outside institutions, examined in the United States in national surveys. The findings are based upon the recollection of individuals with respect to the period of 12 months prior to interview and upon the occurrence of depression in the previous week as indicated by the answers to the Depression Scale of the Centre for Epidemiologic Studies (CES-D). They indicate that 14.4% of the United States population between the ages of 25-74 suffer from definite chronic pain related to the joints and musculoskeletal system. Another 7.4% have some pain of uncertain duration. Eighty-three percent of the definite pain group received treatment. Chronic pain subjects scored significantly higher than normals on the CES-D (10.68 +/- S.E.M. 0.76 vs. 8.05 +/- 0.23, P less than 0.01) with subjects with pain of uncertain duration scoring similar to the definite chronic pain population (11.13 +/- 0.76). Using a high cut-off score for depression. 18% of the population with chronic pain were found to have depression. This is in contrast to 8% of the population who did not have chronic pain.
Allograft reconstructions of the shoulder after bone tumor resections. Large skeletal defects resulting from tumor resections about the shoulder create reconstructive challenges for the orthopedic surgeon. Bone allografts offer several advantages compared with other reconstructive techniques, and functional outcomes are generally satisfactory. They may be used either as osteoarticular grafts, intercalated segments to create an arthrodesis, or in combination with standard proximal humerus metallic implants. Patient expectations and specific oncologic factors must be considered when selecting the optimal method of reconstruction.
Oxygen desaturation during fiberoptic bronchoscopy in pediatric patients. STUDY OBJECTIVE: Pulse oximetry was used to measure arterial oxygen saturation and the extent of hypoxemia in pediatric patients undergoing FB. DESIGN: Arterial oxygen saturation was measured (1) prior to the procedure to provide a baseline value, (2) when the bronchoscope was positioned in the nasopharynx, and (3) when the bronchoscope was positioned in the mid-trachea. SETTING: Fiberoptic bronchoscopy was performed in the Pediatric Special Care Unit or in the Pediatric Pulmonary Laboratory using an Olympus BF3C4 fiberoptic bronchoscope with a 3.5-mm outer diameter. PATIENTS OR PARTICIPANTS: Thirty-six children who underwent diagnostic or therapeutic bronchoscopy for a variety of reasons were evaluated. They ranged in age from 6 to 142 months; 20 were male and 16 were female. INTERVENTIONS: There were no interventions. MEASUREMENTS AND RESULTS: Of the 36 patients, 29 experienced a fall in SaO2 levels exceeding 5 percent of baseline values. The youngest age group, 6 to 12 months, showed the greatest drop in saturation as compared with the other groups. Desaturation was significantly increased by midtracheal FB. CONCLUSIONS: A decline in arterial oxygen saturation that may be substantial in infants and children undergoing FB examination was frequently noted, especially in smaller infants and when the bronchoscope was positioned in the mid-trachea. Supplemental oxygen and a brisk procedure time will minimize the risk of dangerous hypoxia.
Duration of the QT interval and total and cardiovascular mortality in healthy persons (The Framingham Heart Study experience). The baseline electrocardiograms of 5,125 original subjects of the Framingham Heart Study were measured to examine the relation of the QT interval corrected for heart rate (QTc) to risk of total mortality, sudden cardiac death, and death due to coronary artery disease over a 30-year follow-up period. Quintiles of QTc (seconds) less than or equal to 0.36, 0.36 to 0.38, 0.39 to 0.40, 0.41 to 0.43 and greater than or equal to 0.44 were studied in relation to these outcomes. There were no significant differences in the risk of total mortality, sudden cardiac death or death due to coronary artery disease according to QTc. A similar lack of significant association between QTc and these 3 outcomes was observed among all persons studied and in the 2 sexes after using a multiple regression analysis to control for several potentially confounding characteristics including age, gender, cigarette smoking, serum total cholesterol, systolic systemic blood pressure and Framingham relative weight. The results of this study fail to demonstrate an association between baseline QTc and overall mortality, and deaths due to sudden cardiac events or coronary artery disease in a large population-based cohort of essentially healthy persons in whom pathologic forms of QTc prolongation are uncommon.
Non-specific reactions in enzyme linked immunosorbent assays for serum antibody to entamoeba histolytica and Giardia lamblia in non-endemic areas. Serum samples from 20 Indian children with diarrhoea were compared with those from 20 children resident in the United Kingdom who had been diagnosed as having ulcerative colitis, or Crohn's disease, or indeterminate colitis using enzyme linked immunosorbent assays specific for Entamoeba histolytica and Giardia lamblia. More than 50% of the United Kingdom patients had high IgG responses in ELISAs for E histolytica and G lamblia. A confirmatory ELISA showed that the British sera reacted specifically to bovine serum proteins rather than to protozoal antigens. Prior incubation of sera with 5% bovine serum prohibited this reaction. Bovine serum is an integral part of the crude soluble antigen used in most ELISAs for E histolytica and G lamblia and needs to be replaced with purified antigen preparations. The British sera also reacted to other commonly used blocking agents such as bovine serum albumin, casein, and normal sheep serum. These reactions were attributed to uptake of dietary antigens or an enhanced immunological response to these antigens in patients with inflammatory bowel disease.
Sudden death in hypertrophic cardiomyopathy with normal left ventricular mass An active, healthy, and symptom free 16 year old boy with a family history of hypertrophic cardiomyopathy died suddenly while walking home from school. Necropsy showed absence of left ventricular hypertrophy (that is, normal heart weight), though the characteristic histological abnormalities of hypertrophic cardiomyopathy, such as cardiac muscle cell disorganisation and abnormal intramural coronary arteries, were present. It is likely that this patient had hypertrophic cardiomyopathy and died before left ventricular hypertrophy developed.
Gallstone pancreatitis. Gallstone pancreatitis is caused by transient obstruction of the ampulla of Vater by a migrating gallstone. Intraglandular activation of pancreatic enzymes occurs (by an unclear mechanism), and their entry into the circulation causes most of the local and systemic events of pancreatitis. The diagnosis is based on history and physical examination, an elevation of serum amylase above 1000 IU/L, and ultrasound and CT scans. Endoscopic retrograde cholangiopancreatography can be used in less certain cases to confirm the presence of common bile duct stones. Because of the absence of an agent that can abort progression of the disease, therapy should consist of adequate resuscitation, nutritional support, and careful monitoring to detect early complications. In patients with mild pancreatitis, surgery usually can be performed within 48 or 72 hours of admission or as soon as symptoms and amylase levels return to normal. For patients with severe disease, endoscopic sphincterotomy is emerging as the therapeutic modality of choice. Elective treatment of the associated biliary disease should be performed during the same hospitalization after the acute phase of the disease has subsided.
Should family doctors screen asymptomatic children for high blood pressure? Whereas the United States Task Forces on Blood Pressure Control in Children have recommended annual blood pressure screening in all children, a working party of the British Hypertension Society has formed the opposite opinion. Relevant literature is reviewed here, and the conclusion reached that on epidemiological and ethical grounds, screening children for hypertension cannot at present be justified.
Deep femoral to anterior tibial bypass after failed femoropopliteal reconstructions. Deep femoral to anterior tibial artery bypass is a reconstructive technique occasionally applicable when more conventional attempts at revascularization of the distal portion of the leg have failed. Three such patients, in whom the anterior tibial was the only distal patent branch of the popliteal artery, had severe symptoms of arterial insufficiency. Deep femoral to anterior tibial bypass was done using autogenous The distal portion of the deep femoral artery was exposed through an anteromedial distal thigh approach. The three patients have been followed up for a mean of 20.3 months, and each maintains graft patency and marked symptomatic improvement.
Impaired left ventricular filling and regional diastolic asynchrony at rest in coronary artery disease and relation to exercise-induced myocardial ischemia. Impaired left ventricular (LV) diastolic filling at rest is frequently observed in patients with coronary artery disease (CAD) who have normal LV systolic function and no previous infarction. To test the hypothesis that abnormal diastolic function at rest might reflect the functional severity of CAD, as estimated by exercise-induced ischemia, the relation between regional and global LV diastolic function at rest and during exercise-induced ischemia was evaluated in 49 patients with radionuclide angiography. All patients had normal systolic function at rest. Group 1 (n = 26) patients manifested a normal ejection fraction response to exercise and group 2 (n = 23) patients an abnormal response. Data obtained from 22 age-comparable normal volunteers were used for comparison. Although regional and global diastolic function were not different between normal subjects and group 1 patients, peak filling rate was lower in group 2 patients than in normal subjects (2.5 +/- 0.8 vs 3.2 +/- 0.6 end-diastolic counts/s; p less than 0.01). Moreover, regional diastolic asynchrony, as assessed from the radionuclide data by using a regional sector analysis of the LV region of interest, was greater in group 2 patients (46 +/- 44 ms) than in both normal subjects (25 +/- 16 ms; p less than 0.05) and group 1 patients (23 +/- 16 ms; p less than 0.05). Thus, among patients with CAD and with normal LV systolic function at rest, impaired LV filling and regional asynchrony predict a greater degree of exercise-induced ischemia, suggesting a greater extent of jeopardized myocardium.
Thrombosis in a congenitally bifurcated superior sagittal sinus. A 26-year-old woman had a peripartum venous thrombotic stroke involving the right parietal lobe. The initial thrombus was present only in the right channel of a congenitally bifurcated superior sagittal sinus. This diagnosis and subsequent thrombus extension were readily shown by magnetic resonance imaging in contrast to equivocal angiography. A subsequent, prospective review of 100 patients undergoing cranial magnetic resonance imaging showed the presence of similarly bifurcated superior sagittal sinuses in two. The patient stabilized after therapy with intravenous heparin, but switching her medication to oral warfarin sodium was followed by clinical deterioration and propagation of the thrombus, necessitating resumption of intravenous heparin. No coagulopathy was identified.
Resympathectomy of the upper extremity. Resympathectomy was performed in 27 patients (eight bilaterally) with ischaemic hand phenomena. An extended operative technique, resecting parts of the second and third intercostal nerves and their surrounding tissue, was used. In all 35 procedures the posterior extrapleural approach was used. Follow-up was from 3 to 12 years. Only the sympathetic ganglia had been removed during the previous surgery by the axillary approach (67 per cent of these patients had had a transient response for between 6 months and 2 years; 33 per cent had had no response at all). A direct subjective improvement was seen after 27 of the 35 reoperations (77 per cent). In 14 patients continuous wave Doppler ultrasound studies were available and showed a significant increase in peak forward frequency after operation (P less than 0.001). From these data it may be concluded that it is possible to obtain a resympathectomy effect, but reoperation should be reserved for special cases for whom survival of digits is essential.
Antihypertensive effect and pharmacokinetics of nitrendipine in children. Nitrendipine, a new calcium-channel antagonist, was used to treat 25 children (aged 6 months to 17 years) with severe hypertension. Systolic and diastolic blood pressures (mean +/- SEM) fell from 148 +/- 2/99 +/- 2 mm Hg to 128 +/- 4/77 +/- 3 mm Hg after 24 hours and to 121 +/- 2/75 +/- 2 mm Hg after 2 weeks. No further reductions in systolic or diastolic blood pressure were observed after continued therapy. Transient reflex tachycardia occurred during the first week of therapy. Other adverse effects were uncommon and included headaches, flushing, palpitations, and edema. Pharmacokinetic parameters were estimated at steady state after an oral dose of 0.56 +/- 0.04 mg/kg in 13 children. Although absolute oral bioavailability could not be determined, estimates of the area under the plasma concentration versus time curve, the apparent peak serum concentration, and the apparent time at which the peak serum concentration occurred indicated that both the rate of absorption and oral bioavailability are variable. Coadministration of nitrendipine with food decreased the rate of absorption and may have reduced oral bioavailability. A relationship between age and the apparent plasma elimination half-life of nitrendipine was not observed. Nitrendipine, 0.25 to 0.5 mg/kg per dose administered orally every 6 to 12 hours, appeared to be an effective and safe treatment for resistant hypertension in infants and children.
Cellular immune response to hepatitis B virus-encoded antigens in acute and chronic hepatitis B virus infection. The proliferative response of PBMC to hepatitis B virus (HBV) envelope, core, and e Ag was analyzed prospectively in 21 patients with acute self-limited HBV infection and compared with the response of patients with chronic HBV infection and different levels of HBV replication (i.e., hepatitis e Ag (HBeAg)- or anti-HBe-positive) and liver damage (i.e., chronic active hepatitis or chronic asymptomatic carriers). Our results indicate that: 1) HBV-infected subjects who develop a self-limited acute hepatitis show a vigorous PBMC response to hepatitis B core Ag and HBeAg, as expression of T cell activation; 2) appearance of a detectable lymphocyte response to HBV nucleocapsid Ag is temporally associated with the clearance of HBV envelope Ag; 3) in patients with chronic HBV infection the level of T cell responsiveness to hepatitis B core Ag and to HBeAg is significantly lower than that observed during acute infection; 4) T cell sensitization to HBV envelope Ag in acute and chronic HBV infection is usually undetectable and when measurable is expressed transiently and at low levels. These results may reflect immune events of pathogenetic relevance with respect to evolution of disease and viral clearance.
Endogenous opioids modulate the increase in ventilatory output and dyspnea during severe acute bronchoconstriction. The aim of this study was to evaluate whether endogenous opioids are involved in the regulation of breathing pattern and respiratory drive during bronchoconstriction induced by methacholine (MCh). We studied six male asymptomatic asthmatics 18 to 35 yr of age. In a preliminary study we determined the concentration of MCh causing a 60% fall in FEV1 (PC60 FEV1). On two subsequent days, we measured breathing pattern, dyspnea sensation (Borg scale), mouth occlusion pressure (P0.1), and FEV1 before and 10 min after an intravenous injection of either naloxone (0.1 mg/kg) or saline according to a randomized double-blind crossover design. A MCh concentration equal to the PC60 FEV1 was then inhaled, and measurements were repeated 5 min later. Neither placebo nor naloxone affected baseline breathing pattern, P0.1, and FEV1. Naloxone pretreatment did not influence airway response to MCh; the mean percent fall in FEV1 was 65.9 +/- 1.3 and 64.7 +/- 1.2% (mean +/- 1 SE) on the placebo day and the naloxone day, respectively. After MCh inhalation no significant changes in VE, VT, and breathing frequency occurred when patients received placebo. However, P0.1 increased from 1.48 +/- 0.17 to 3.43 +/- 0.70 cm H2O (p less than 0.05), and VT/TI fell from 0.66 +/- 0.08 to 0.52 +/- 0.04 L/s (p less than 0.05). Naloxone pretreatment resulted in an increase in breathing frequency (from 18.2 +/- 1.7 to 22.8 +/- 2.6 breaths/min; p less than 0.05) and VT/TI (from 0.58 +/- 0.06 to 0.74 +/- 0.05 L/s; p less than 0.05) after MCh.
Epirubicin cardiotoxicity: a study of 135 patients with advanced breast cancer. The cardiotoxicity of epirubicin (EPI) was evaluated clinically, radiologically, with ECG, and with multiple ECG-gated radionuclide determination of the left ventricular ejection fraction (LVEF) during rest in 135 patients with advanced breast cancer. The EPI doses were 60 mg/m2 on days 1 and 8 every 4 weeks or 45 mg/m2 plus vindesine 3 mg/m2 on the same schedule. The median cumulative dose of EPI was 500 mg/m2 (range, 47 to 1,563). Eight of the 135 patients developed congestive heart failure (CHF). Of 67 patients treated with EPI less than 500 mg/m2, none developed CHF. Among 48 patients treated with doses between 500 and 1,000 mg/m2, one had CHF (2%; 95% confidence limits, 0.1 to 11.1). Among 20 patients who received EPI from 1,000 to 1,563 mg/m2, seven developed CHF (35%; 95% confidence limits, 15.4 to 59.2). Four patients died due to cardiotoxicity. The risk of EPI cardiotoxicity at the present schedule is considerable at doses above 1,000 mg/m2. At doses between 500 and 1,000 mg/m2 the risk of CHF decreases, and at doses below 500 mg/m2, it is negligible. For all patients, the prevalence of CHF was 6% and the sensitivity of LVEF high (95%), mainly due to the low incidence of CHF. Among the 20 patients who received EPI at more than 1,000 mg/m2, the prevalence of CHF was 35% and the sensitivity only 64%. The specificity was maximally 62%. Our results suggest that LVEF is of no value as a predictor for CHF.
Pituitary hemorrhage into a Rathke's cleft cyst This report describes a case of symptomatic pituitary hemorrhage into a Rathke's cleft cyst in a 25-year-old woman. The literature on pituitary hemorrhage in nonadenomatous sellar tumors is reviewed.
Breast cancer screening: who should be included? The recommendations of the U.S. Preventive Services Task Force are reviewed in regard to screening for breast cancer. In contradistinction to those issued by some other national organizations, screening for breast cancer using mammography at ages 40-49 is not recommended. It is concluded that the scientific evidence is insufficient at present to recommend mammography screening for women aged 40-49. The recommendations of the task force are: all women over age 40 should receive an annual breast examination; all women should have mammography every one or two years beginning at age 50 and concluding at approximately age 75 unless disease has been detected; and it may be prudent to begin mammography at an earlier age for women at high risk of breast cancer. These recommendations are appropriate in light of the available evidence; though at present there is no evidence that clinical examination of the breasts at any age reduces breast cancer mortality; the upper age beyond which breast cancer screening no longer has a significant effect in reducing breast cancer mortality is unknown; and there is no evidence that women at high risk for breast cancer benefit to a different degree from screening than women not at high risk.
Heparin skin necrosis: delayed occurrence in a patient on hemodialysis. A case of skin necrosis in a patient receiving intravenous (IV) heparin during routine intermittent hemodialysis is reported. Multiple erythematous, tender lesions developed over the abdomen and thighs and rapidly became necrotic. Biopsies showed fibrin thrombi in the dermal venules and capillaries, but no cellular infiltrate. The patient was in her third month of regular hemodialysis. Skin necrosis associated with the use of heparin usually occurs within 2 weeks of beginning heparin therapy and has not been reported in patients receiving heparin with hemodialysis. Possible mechanisms, including acquired antithrombin III deficiency leading to heparin-induced skin necrosis, are discussed.