shukoor65/lab-rag-model huggingface dataset:
Assessment of the human coronary circulation using a Doppler catheter. Arteriographic estimates of stenosis severity can fail to reflect the impact of an individual stenosis on delivery of blood to the myocardium. Whether a coronary stenosis is truly flow-limiting can be determined by measuring hyperemic blood flow or coronary flow reserve; however, until recently, the tools needed to measure coronary flow reserve in humans--namely, a method of quantitating coronary blood flow in individual arteries and another method for producing maximal microvascular vasodilation--were not available. Over the last 8 years, our laboratory group has developed a catheter for measuring coronary blood flow velocity in humans, using the Doppler principle, and studied the effects of microvascular vasodilators. These studies have enabled us to measure coronary flow reserve in humans and to characterize some of the effects of focal and diffuse atherosclerosis on the coronary circulation. In addition, we have used flow reserve measurements in the diagnosis of microvascular dysfunction in patients with chest pain and normal coronary arteries and as a means of assessing noninvasive methods for detecting focal coronary artery disease.
Phenotypic heterogeneity in the syndromes of 3-methylglutaconic aciduria. Combined 3-methylglutaconic and 3-methylglutaric aciduria, one of the more common urinary organic acid abnormalities, has been observed in at least three clinical syndromes. We studied an additional seven patients with 3-methylglutaconic aciduria, four of whom were best categorized as having the type II syndrome, two as having an "unspecified" syndrome, and one who may have had a primary urea cycle defect. In cultured cells and autopsy tissues derived from patients with the type II and unspecified syndromes, we were unsuccessful in identifying a defect in the leucine degradative pathway distal to 3-methylcrotonyl-coenzyme A carboxylase and in the cholesterol biosynthetic pathway between 3-hydroxy-3-methylglutaryl-coenzyme A reductase and diphosphomevalonate decarboxylase. Further assessment of the cholesterol biosynthetic pathway in several patients with one of the two types of disease also provided no defined abnormality. The primary metabolic defects in the type II and unspecified syndromes remain undefined.
Efficacy and safety of a perioperative enoxaparin regimen in total hip replacement under various anesthesias. Four trials in which enoxaparin, a low-molecular-weight heparin, was used in patients having hip surgery are reported. In the first two trials, enoxaparin was given before general anesthesia. The protocol consisted of 40 mg of enoxaparin, 4,000 anti-factor Xa IU, subcutaneously 12 hours before surgery, followed by the same dose 12 hours after surgery and then once daily. In the third trial, this protocol was compared with unfractionated heparin calcium given in a standardized manner and appeared to be significantly superior both in efficacy and tolerance. In the fourth trial, the protocol was adapted for use in spinal subarachnoidal anesthesia; 20 mg of enoxaparin, 2,000 anti-factor Xa IU, was given subcutaneously 1 hour after anesthesia and 40 mg 12 hours later. In all these trials tolerance was good. Excessive bleeding did not occur with the 40 mg once daily regimen. Efficacy was good and compared favorably with other protocols in use.
Calcium channel blockers. Potential medical benefits and side effects. Calcium channel blockers are recently developed antihypertensive drugs. In terms of mechanisms of action, their specificity is not so well established as that of angiotensin converting enzyme inhibitors but is better understood than that for diuretics or adrenergic-inhibiting drugs. Calcium channel blockers were originally developed for treatment of angina but were found to lower arterial pressure as well. Three of them are now in wide use in the United States; their therapeutic spectrum in regard to type of hypertension is broad. Sublingual nifedipine has replaced intravenously administered vasodilators as immediate treatment of severe hypertension, and all three drugs, given orally, have been shown to be effective in mild, moderate, and severe hypertension. The three drugs available in this country are verapamil, diltiazem, and nifedipine. Pharmacological studies have shown that verapamil has the most negative chronotropic and inotropic effects of the three, with nifedipine producing the most vasodilation and having the potential for causing reflex tachycardia. Actually in practice, these various pharmacological differences have proved to have less significance than previously thought, and the drugs seem to have about equal antihypertensive effectiveness. Comparisons of calcium entry blockers with other drugs have shown them to be equally effective in whites as propranolol but more effective in blacks. Responsiveness appears to be related, as well, to pretreatment plasma renin activity and age. Thus, the antihypertensive effect is directly related to age and inversely related to plasma renin activity. The side effects mostly relate to vasodilation, reflex tachycardia, palpitations, headache, and edema; they are not frequent, and the drugs are well tolerated.
Influence of phlebographic abnormalities on the natural history of venous ulceration. Eighty-five limbs in 73 patients with a healed venous ulcer were assessed by ascending and descending phlebography, foot volume plethysmography and transcutaneous oxygen measurements. Forty-four limbs had post-thrombotic changes on ascending phlebography. In 24 (28 per cent) these extended into the femoral vein, while in 20 (24 per cent) only the calf veins were involved. In the 41 limbs (48 per cent) with normal deep veins on ascending phlebography, 11 had evidence of localized incompetence of the calf communicating veins, 14 had either long saphenous incompetence, deep vein reflux to the level of the knee or below, or both of these abnormalities, and 16 limbs had no phlebographic abnormalities. However all limbs had a decreased half volume refilling time on foot volume plethysmography. Limbs with post-thrombotic changes extending into the femoral vein were associated with a significantly longer history of ulceration and more ulcer recurrences than limbs with calf vein damage (P less than 0.05 for each) and limbs with normal deep veins (P less than 0.01 for each). However, these limbs did not have lower transcutaneous oxygen ratios or longer times to achieve ulcer healing. Ascending phlebography identified a group of limbs with extensive post-thrombotic changes in which there was a higher incidence of ulcer breakdown, but this was not associated with a delay in ulcer healing.
Liver enzyme abnormalities in Parkinson's disease. If toxicant exposure contributes to the cause of Parkinson's disease, poor function of detoxifying enzymes could increase vulnerability for Parkinson's disease. Although no hepatic enzyme system has been shown universally to be dysfunctional in Parkinson's disease patients, several have been suggested to be dysfunctional in subgroups, such as those with young age at disease onset. Specific enzymes implicated include several P450 enzymes, most notably P450 IID6, and cysteine dioxygenase. If hepatic enzyme abnormalities contribute to the development of Parkinson's disease, molecular genetic techniques may allow the development of screening tests to identify at-risk subjects in order to intervene with protective therapies.
Splenectomy does not correlate with length of survival in patients undergoing curative total gastrectomy for gastric carcinoma. Univariate and multivariate analyses. The relationship between splenectomy and survival time after curative total gastrectomy for advanced gastric cancer was examined by reviewing retrospectively data on 252 patients treated in our clinics between 1965 and 1985. One hundred three patients (40.9%) did not undergo splenectomy and 149 (59.1%) did. In patients subjected to splenectomy, advanced stages of the malignancy were more frequent and metastasis was noticed in 8.1% of splenic hilar lymph nodes and in 10.1% of the lymph nodes associated with the splenic artery. A univariate analysis revealed that the survival time of patients with splenectomy was significantly less than those for whom splenectomy was not done (P less than 0.05). In a subgroup of our patients stratified to adjust for the stage of disease, there was no significant difference between the survival rates. Subsequently, multivariate analysis using the Cox regression analysis adjusted for sex, age, and other covariates indicated that serosa invasion, lymph node metastasis, and tumor size were the most important prognostic factors, and there was no correlation whatever with splenectomy. Our findings rule out any relationship between splenectomy and length of survival time in patients undergoing curative total gastrectomy for advanced gastric cancer.
Preservation of hearing in neurofibromatosis 2. Preservation of hearing in the neurofibromatosis 2 (central neurofibromatosis) patient has been infrequently documented. This goal can be attained in selected patients and should be more frequently accomplished in the future with improved diagnostic capabilities and improved surgical techniques. We report three patients in whom this elusive goal has been accomplished.
Comparison of exercise testing with studies of coronary flow reserve in patients with microvascular angina. Abnormal small coronary artery function may cause limited coronary flow responses to stress, resulting in anginal symptoms and ischemia in some patients with chest pain despite angiographically normal coronary arteries. To assess the exercise hemodynamic correlates of coronary flow abnormalities measured in the cardiac catheterization laboratory, 105 patients with microvascular angina (defined as an increase in coronary vascular resistance during pacing stress after ergonovine administration in the absence of significant epicardial constriction and associated with provocation of the patient's typical chest pain) and 27 patients without any coronary flow abnormality (normal) were analyzed. Of the 105 patients with microvascular angina, 75 had normal electrocardiographic responses to treadmill exercise testing, 22 had ischemic responses, and eight had bundle branch block during exercise. All 27 normal patients had normal electrocardiographic responses to exercise. Patients with ischemic electrocardiographic responses (0 +/- 7%, p less than 0.01), and those with bundle branch block (-2 +/- 6%, p less than 0.01) had abnormal left ventricular ejection fraction responses to exercise compared with the normal group, who demonstrated an 8 +/- 6% increase in left ventricular ejection fraction by radionuclide angiography during exercise, and microvascular angina patients with a normal electrocardiographic response to exercise, who demonstrated a 5 +/- 7% increase in ejection fraction. Although the microvascular response to ergonovine was no different among the three microvascular angina exercise groups, the administration of dipyridamole caused less coronary vasodilation in those patients with apparently ischemic or bundle branch block responses to exercise compared with those with normal electrocardiograms during exercise.
Natriuretic peptides as cardiac hormones in normotensive and spontaneously hypertensive rats. The ventricle is a major site of synthesis and secretion of brain natriuretic peptide. To study synthesis, storage, and secretion of brain natriuretic peptide (BNP) in the heart, we have measured BNP mRNA and BNP concentrations in the hearts of Wistar-Kyoto rats and also have investigated its secretion from the isolated perfused heart. The atrium expressed the BNP gene at a high level, and a considerable amount of BNP mRNA also was present in the ventricle, which corresponded to approximately 40% of the atrial BNP mRNA concentration. When tissue weight was taken into account, the total content of BNP mRNA in the ventricle was approximately threefold larger than that in the atrium, although the atrial natriuretic peptide (ANP) mRNA content in the ventricle was only 7% of that in the atrium. By contrast, the BNP concentration in the ventricle was 4.07 +/- 0.97 pmol/g, which was less than 1% of that in the atrium (451 +/- 86 pmol/g). The basal secretory rate of BNP from the isolated perfused whole heart was 49.3 +/- 6.1 fmol/min, approximately 60% of which was maintained even after atrial removal, whereas the secretory rate of ANP was reduced to less than 5%. We also studied age-matched spontaneously hypertensive rats-stroke prone. The rank order of the BNP mRNA concentration in the hearts of these rats was left ventricle greater than right ventricle greater than right atrium = left atrium, and the total BNP mRNA content and BNP secretory rate in the ventricle were twice as large as in Wistar-Kyoto rats. These results demonstrate that BNP is a novel cardiac hormone in rats and is predominantly synthesized in and secreted from the ventricle. This is in striking contrast to ANP, which occurs mainly in the atrium. The results also suggest possible pathophysiological roles of BNP in certain cardiovascular disorders.
Randomized trial of salbutamol in acute bronchiolitis. To test whether nebulized salbutamol (albuterol) is safe and efficacious for the treatment of young children with acute bronchiolitis, we enrolled 83 children (median age 6 months, range 1 to 21 months) in a randomized, double-blind clinical trial. Participants received two treatments at 30-minute intervals of either nebulized salbutamol (0.10 mg/kg in 2 ml 0.9% saline solution) or a similar volume of 0.9% saline solution placebo. Outcome measures were the respiratory rate, pulse oximetry, and a clinical score based on the degree of wheezing and retractions. Patients in the salbutamol arm had significantly greater improvement in clinical scores after the initial treatment (p = 0.04). There was no difference between the groups in oxygen saturation (p = 0.74); patients treated with salbutamol had a small increase in heart rate after two treatments (159 +/- 16 vs 151 +/- 16; p = 0.03). We conclude that salbutamol is safe and effective for the initial treatment of young children with acute bronchiolitis.
Altered stores of atrial natriuretic peptide in specific brain nuclei of NaCl-sensitive spontaneously hypertensive rats. Previous studies from our laboratories have demonstrated a selective increase in stores of atrial natriuretic peptide (ANP) in the anterior hypothalamus of NaCl-sensitive spontaneously hypertensive rats (SHR-S) compared to NaCl-resistant Wistar-Kyoto (WKY) controls and have suggested that anterior hypothalamic ANP contributes to the pathogenesis of NaCl-sensitive hypertension in SHR-S by local inhibition of norepinephrine release. We have also observed blunting of cardiopulmonary and arterial baroreflex function in SHR-S compared to WKY. In the current study, ANP stores in 12 brain nuclei thought to participate in the pathogenesis of hypertension, including locus coeruleus (LC), A1/C1 area (A1/C1), nucleus tractus solitarii (NTS), medial preoptic nucleus (MPON), suprachiasmatic nucleus (SCN), supraoptic nucleus (SON), anterior hypothalamic area (AHA), paraventricular hypothalamic nucleus (PVN), ventromedial hypothalamic nucleus (VMN), dorsomedial hypothalamic nucleus (DMN), lateral hypothalamic nucleus (LN), and posterior hypothalamic area (PHA), were compared in 10-week-old male SHR-S and WKY rats following 3 weeks of 1% v 8% NaCl feeding. Individual brain nuclei were obtained by the micropunch technique and ANP content of bilateral brain nuclei from individual rats was measured by radioimmunoassay. ANP content was significantly decreased in NTS and LC and elevated in AHA of SHR-S compared to WKY rats on either diet. Dietary NaCl supplementation was associated with increased ANP content in PVN of both strains. These alterations in ANP content in SHR-S may be related to the reduced release of norepinephrine from nerve terminals in AHA and to the presumed central defect in baroreceptor function.
Manifestations of pulmonary cryptococcosis in patients with acquired immunodeficiency syndrome. Cryptococcosis is a common opportunistic infection in patients with AIDS. Meningitis is the most frequent manifestation of infection with Cryptococcus neoformans; pneumonia due to this organism, though less frequently recognized, is also a significant entity. A retrospective review was performed of all patients seen at Duke University Medical Center between January 1981 and July 1989 who were infected with both human immunodeficiency virus type 1 and C. neoformans. Of 31 patients with these concomitant infections, 12 had cryptococcal pneumonia (10 definite and two presumptive cases). Eleven of these 12 patients had evidence of extrapulmonary cryptococcal disease as well. Chest radiography showed interstitial infiltrates in 11 instances. For ten of the 12 patients, pulmonary cultures were positive for C. neoformans. Bronchoalveolar lavage fluid from all five patients who underwent bronchoscopy yielded the organism. Acute-phase mortality from cryptococcosis was 42% among patients with pneumonia. Cryptococcal pneumonia in patients with AIDS is probably more common than has previously been recognized and typically presents as interstitial disease that may mimic other opportunistic infections.
Expression of interleukin-4 receptors on early human B-lineage cells. Interleukin-4 (IL-4) regulates multiple stages of the antigen-dependent phase of B-cell development. However, its precise role in regulating B lymphopoiesis in bone marrow is not as well defined. We examined whether surface IgM- normal and leukemic human B-cell precursors (BCP) expressed IL-4 receptors using biotinylated IL-4. Constitutive expression of IL-4 receptors was detected on both normal and leukemic BCP. A higher percentage of normal BCP (82% +/- 15%) expressed IL-4 receptors compared with leukemic BCP (44% +/- 8%). Using mean fluorescent intensity as an indicator of receptor level on the IL-4 receptor positive cells, normal (91 +/- 41) and leukemic (44 +/- 37) BCP expressed comparable numbers of receptors. IL-4 induced the expression of CD23 on 30% of the leukemic BCP cases examined. IL-4 induced CD23 on surface IgM+ fetal bone marrow lymphoid cells but not on the surface IgM- normal BCP, despite the presence of detectable receptors on the surface IgM- cells. IL-4 did not stimulate proliferation of normal BCP, nor could it enhance the effect of recombinant IL-7 or low molecular weight B-cell growth factor. However, IL-4 increased the expression of surface IgM and surface Ig kappa on in vitro differentiated pre-B cells. Our collective results identify no role for IL-4 in the proliferation of normal or leukemic BCP, but identify a role in the enhancement of surface Ig expression during pre-B to B-cell differentiation.
Luteinizing hormone-releasing hormone alters the hypothalamic effects of morphine in the rat. Female rats exhibit a generalized refractoriness to opiate stimulation during periods of steroid-induced LH secretion. In the present study we evaluated that role of LHRH in this steroid-induced effect on opiate-responsiveness. Central administration to ovariectomized rats of native LHRH or the LHRH agonist [Des-Gly10]LHRH ethylamide causes a dose-dependent refractoriness to the hypothermic effects of morphine. The potency relationship of these two LHRH agonists in antagonizing morphine's effect was consistent with their potency in inducing LH release. Treatment of ovariectomized rats with estradiol benzoate and progesterone in a regimen which induces a preovulatory-like LH surge, antagonized morphine-induced hypothermia, and the LHRH antagonist [D-Phe2, Pro3, D-Phe6] LHRH, reversed the effects of the gonadal steroids. These results indicate that the LHRH secretory dynamics associated with the preovulatory surge of LH may serve to modulate opiate responsiveness and thereby could serve to couple behavioral, sensory, and autonomic events with this neuroendocrine response to gonadal steroids.
Latissimus dorsi musculocutaneous flap for elbow extension. The latissimus dorsi mycocutaneous flap has developed a reputation for its versatility in both skin and soft tissue coverage and for restoration of elbow function in both flexion and extension. In a case presented, a large extra-abdominal desmoid was removed along with the entire deltoid and three-quarters of the triceps. The latissimus dorsi was elevated with a large overlying skin island and rotated on its neurovascular pedicle into the defect in the posterior shoulder and upper arm to replace the resected triceps and deltoid muscle, and to provide coverage in this region.
Program to increase the accessibility of screening mammography--Rhode Island, 1987-1988. The Rhode Island Department of Health's (RIDH) Breast Cancer Screening Program (RIBCSP) was initiated in 1987; it includes a broad promotional effort targeting women and physicians, a strong quality-assurance program, reductions in the cost of the breast cancer screening examination, and a telephone appointment and tracking system for screening examinations and follow-up care. This report describes and summarizes an evaluation of the RIBCSP.
The interferons. Mechanisms of action and clinical applications. The interferons (IFN) are one of the body's natural defensive responses to such foreign components as microbes, tumors, and antigens. The IFN response begins with the production of the IFN proteins (alpha, beta, and gamma), which then induce the antiviral, antimicrobial, antitumor, and immunomodulatory actions of IFN. Recent advances have led to Food and Drug Administration approval of five clinical indications for IFN. Interferon alfa is approved for hairy-cell leukemia, condyloma acuminatum, Kaposi's sarcoma in the acquired immunodeficiency syndrome, and non-A, non-B (type C) viral hepatitis. Interferon gamma has properties distinctive from those of IFNs alpha and beta and is approved as an immunomodulatory treatment for chronic granulomatous disease. Promising clinical results with IFNs have also been reported for basal cell carcinoma, chronic myelogenous leukemia, cutaneous squamous cell carcinoma, early human immunodeficiency virus infection, hepatitis B, and laryngeal papillomatosis. Future clinical uses of IFNs may emphasize combination therapy with other cytokines, chemotherapy, radiation, surgery, hyperthermia, or hormones.
Lichen sclerosus et atrophicus in children. The symptoms, findings, associated conditions, and treatment of lichen sclerosus et atrophicus were studied in 10 girls and one boy. Lichen sclerosus et atrophicus is a benign but chronic condition of the anogenital area of girls and, less frequently, of boys. The characteristic lesions are hypo-pigmented plaques in a figure-of-8 pattern surrounding the vulva and anus and often involving the natal cleft. The affected hypopigmented skin is sharply demarcated from the normal skin. Hemorrhagic, bullous lesions are uncommon. Fissures and ulcers are seen on the labia, between the labia, and on the perineum, anus, and natal cleft in many children and on the glans penis in boys. Lichen sclerosus et atrophicus causes painful defecation and anal and vulval bleeding. In two patients, one girl and one boy, anal stenosis due to lichen sclerosus et atrophicus and laxative treatment developed. Lichen sclerosus et atrophicus mimics sexual abuse and has led to false accusation and investigations. The anogenital lesions cleared in three patients at the ages of 9, 11, and 12 years, but lesions can persist into adulthood.