123rc/medical_text huggingface dataset:
Murine retroviral neurovirulence correlates with an enhanced ability ofvirus to infect selectively, replicate in, and activate resident microglial cells [published erratum appears in Am J Pathol 1991 May;138(5):1058] To determine the biologic basis of ts1 MoMuLV neurovirulence in vivo, newborn CFW/D mice were inoculated with neurovirulent ts1 MoMuLV and nonneurovirulent wt MoMuLV and the temporal response to virus infection in the central nervous system (CNS), spleen, and thymus was studied comparatively. Experimental procedures included single and double labeling in situ immunohistochemistry with selective morphometric analyses, and steady state immunoblotting of viral proteins. Cellular targets for virus infection were identical for both ts1 and wt MoMuLV and consisted sequentially of 1) splenic megakaryocytes, 2) splenic and thymic lymphocytes, 3) CNS capillary endothelial cells, and 4) CNS pericytes and microglia. Resident microglial cells served as the major reservor and amplifier of virus infection in the CNS of ts1 MoMuLV-infected mice; a similar but much less significant role was played by microglia in wt MoMuLV-infected mice. The genesis and progression of severe spongiform lesions in ts1 MoMuLV-infected mice were both temporally and spatially correlated with amplified virus infection of microglia, and hyperplasia and hypertrophy of both virus-infected and nonvirus-infected microglial cells. Direct virus infection of neurons was never observed. The development of clinical neurologic disease and spongiform lesions in ts1 MoMuLV-infected mice correlated with the accumulation of both viral gag and env gene products in the CNS; there was no selective accumulation of env precursor polyprotein Pr80env. When compared to wt MoMuLV-infected mice, the neurovirulence of ts1 MoMuLV-infected mice occurred by an enhanced ability to replicate in the CNS and to infect and activate more microglia, rather than by a fundamental change in cellular tropism or topography of virus infection.
Oromandibular disorders and headache. A critical appraisal. Oromandibular disorders are functional disorders and associated pains in the anatomic region of the temporomandibular joint. Their diagnosis and treatment are controversial because of the lack of conformity concerning these disorders among health care providers. This article provides a clear classification of these disorders and critically reviews their evaluation and treatment.
Coronary artery disease in African-Americans. Contrary to opinions generally accepted in the past, CHD is very common in both African-American men and women, with incidence rates approaching those of US Caucasians. Higher prevalence of hypertension, diabetes, cigarette smoking, and obesity all contribute to the high level of CHD in African-Americans. Additional research is needed about the interrelations and management of various risk factors for CHD in African-Americans outside of the sudden death of African-Americans outside of the hospital is urgent, and special attention should be given to accessibility and use of health services by minority populations.
Supportive evidence for the validity of the epidemiologic necropsy for gallstones OBJECTIVE: The epidemiologic necropsy measures the occurrence of unsuspected disease through the examination of necropsy records of patients who died for other reasons. The estimates of unsuspected disease derived from the epidemiologic necropsy should approximate what actually occurs in the living population. DESIGN/SETTING: To test this hypothesis, all necropsy records of adult patients at the University of Kansas Medical Center from 1950 to 1984 were examined for the presence of gallstones. Patients with previous cholecystectomy or whose gallstones were diagnosed during life were excluded. The data were stratified by age and race and compared with those of a screening survey from Canada, a surgical series from New York, two screening surveys from Italy, and one from Denmark. The crude necropsy detection rates and the rates from the screening surveys were standardized to the 1970 federal census for Kansas City. RESULTS/CONCLUSIONS: The standardized occurrence rates were similar and suggest that the epidemiologic necropsy accurately assesses the occurrence of asymptomatic gallstones in the living population, thus strengthening its validity as a research tool.
Studies on autoimmunity for initiation of beta-cell destruction. VII. Evidence for antigenic changes on beta-cells leading to autoimmune destruction of beta-cells in BB rats. The diabetic syndrome in BioBreeding (BB) rats is believed to result from the destruction of beta-cells by autoimmune responses. However, the initial events that cause the autoimmune destruction of beta-cells remain largely unknown. This investigation was initiated to see whether there are any antigenic changes on the beta-cells from neonatal to adult BB rats that may lead to the autoimmune destruction of beta-cells. Pancreatic grafts from neonatal BB rats remained largely intact without insulitis when transplanted into the renal subcapsular space of acutely diabetic BB rats. Similarly transplanted islet grafts from neonatal BB rats were also not subject to autoimmune destruction. In contrast, islet grafts obtained from adult BB rats, which had been treated with silica to prevent insulitis, were rapidly destroyed in diabetic recipients. These results indicate that beta-cells from neonatal BB rats are different from beta-cells from adult BB rats, at least regarding their recognition by immunologic effectors. Considering our observations and previous information on the initial role of macrophages/dendritic cells in the development of insulitis in BB rats, we suggest that beta-cell-specific antigenic changes that precede insulitis may result in the autoimmune destruction of beta-cells in BB rats.
Results of treatment of persistent hyperplastic primary vitreous. The records of 48 patients with persistent hyperplastic primary vitreous (PHPV) were reviewed. Approximately 17% had vision of 20/100 or better after surgery, contact lens fitting, and amblyopia therapy. Only eyes with a purely anterior presentation had successful visual outcomes. Lensectomy alone prevented glaucoma, but a membranectomy as well was required to ensure a successful visual result. Eyes with a posterior PHPV had poor visual results because of posterior pole abnormalities. I recommend that an attempt be made to visually salvage eyes with an anterior presentation. Eyes with a posterior or a combination anterior-posterior PHPV can be successfully treated for glaucoma, but the visual results will be poor.
Calcium transport by plasma membranes from a glucose-responsive rat insulinoma. Inside-out plasma membrane vesicles from a glucose-responsive rat insulinoma showed an ATP- and Mg2(+)-dependent uptake of Ca2+. The Km (concentration giving half-maximal activity) for Ca2+ was 60 nM. In the presence of 0.4 microM free Ca2+, the Km for ATP was 15 microM, and the Km for Mg2+ was 4 microM. Glucose (30 mM) decreased Ca2+ uptake by 50%, while other insulin secretagogues had no effect, except for glyceraldehyde, which stimulated Ca2+ uptake. Calmodulin increased the uptake of Ca2+, while trifluoperazine and vanadate inhibited the uptake. The Ca2(+)- and Mg2(+)-dependent ATPase from this tumor has a 10- to 20-fold higher requirement for Ca2+, which suggests that this enzyme is not responsible for Ca2+ transport, rather, Ca2+ transport activity represents only a small fraction of the total Ca2(+)-ATPase activity. The physiological importance of Ca2+ transport in insulin secretion is evident from the inhibition of Ca2+ uptake by glucose, which leads to a decrease in Ca2+ efflux from the cell. This inhibition would lead to an increase in intracellular free Ca2+ and insulin release.
Thallium-201 stress scintigraphy in Takayasu arteritis. Thirty-eight women with Takayasu arteritis were studied using thallium-201 stress myocardial scintigraphy to assess the prevalence and pathophysiology of the perfusion abnormality. Twenty (53%) had abnormal scintigraphic findings (group A). Abnormal scans were divided into 3 groups: permanent defects in 6, reversible defects in 7 and slow washout in 7. The remaining 18 patients had normal scintigrams (group N). Group A had a tendency to be older and to have a high prevalence of complicated significant aortic regurgitation. Interventricular thickness plus left ventricular posterior wall thickness (26 +/- 7 vs 17 +/- 2 mm, p less than 0.01) and left ventricular mass (267 +/- 121 vs 133 +/- 39 g, p less than 0.01) were all greater in group A on echocardiography. The mean value of the central aortic pressure in systole was 170 +/- 15 mm Hg in the 7 catheterized patients in group A. Coronary ostial stenoses were present in 2 group A patients who showed reversible defects on scintigrams. These data indicate that the abnormal perfusion detected by imaging in patients with Takayasu arteritis was responsible for a decrease in coronary reserve or myocardial damage, or both, due to long-standing systemic hypertension or aortic regurgitation. Coronary artery disease should be considered if a reversible defect is present.
Direct vasopressor effect of recombinant human erythropoietin on renal resistance vessels. The contractile properties of recombinant human erythropoietin (rHuEPO) on isolated resistance vessels of renal and mesenteric vascular beds were studied in an in vitro model using a small vessel myograph. Under isometric conditions, rHuEPO caused a contraction of this vasculature in a concentration range between 10 U/ml and 200 U/ml. A maximal active wall tension of 1.52 +/- 0.19 mN/mm was obtained under a rHuEPO dose of 200 U/ml. In Ca2+ free solution, the pressor response to high rHuEPO-concentrations was attenuated, and the response to low rHuEPO concentrations was abolished. In the presence of verapamil, phentolamine and saralasin, rHuEPO-induced contractions were not affected significantly. A dose-dependent vasodilatation of mounted vasculature to acetylcholine (ACh) indicated that endothelium remained intact in our preparations. rHuEPO-induced vessel contraction was not abrogated after an enzymatical removal of endothelium by collagenase, confirming that the described contractile responses are endothelial independent. These findings suggest that a direct vasopressor effect of rHuEPO on proximal resistance vessels may contribute to development of hypertension seen in rHuEPO-treated hemodialysis patients.
The use of in situ hybridization to show human papillomavirus deoxyribonucleic acid in metastatic cancer cells within lymph nodes. Southern blot hybridization has been used to identify human papillomavirus types in both primary tumors and lymph node metastases. However, this technique requires fresh-frozen tissue and is incapable of localizing deoxyribonucleic acid sequences to specific cell types in the tumor sample. In contrast, in situ hybridization precisely locates viral sequences within tumor cells while preserving cellular architecture. Further, in situ hybridization requires only small samples of formalin-fixed, paraffin-embedded tissues. Five lymph nodes (from four patients) containing metastatic cervical squamous tumor cells (identified with hematoxylin and eosinophil staining) were analyzed with in situ hybridization techniques with human papillomavirus type 16 deoxyribonucleic acid probes labeled with sulfur 35. The primary cervical cancer from all four patients had been shown to contain human papillomavirus type 16 sequences by Southern blot. Three specimens from two patients clearly showed the presence of human papillomavirus type 16 sequences within the nuclei of metastatic tumor cells, whereas two specimens were nondiagnostic most likely as a result of the small volume of cancer relative to the size of the lymph node. This information indicates that it is the tumor cells themselves that contain viral deoxyribonucleic acid and provides additional evidence linking human papillomavirus with cervical carcinogenesis.
Diagnostic significance of carcinoembryonic antigen in the differential diagnosis of malignant mesothelioma. The histologic and cytologic distinction of malignant mesothelioma from carcinomas metastatic to the pleura or peritoneum is often problematic. For this reason immunologic methods are being increasingly used as diagnostic adjuncts. This review summarizes 40 studies on the expression of carcinoembryonic antigen in mesotheliomas and in lung and other carcinomas involving the pleura or peritoneum. Carcinoembryonic antigen was identified immunohistochemically in 11% of mesotheliomas and in 84% of carcinomas examined and immunocytochemically (in serous effusions) in 4% and 58%, respectively. In serum and in pleural or ascitic fluid, significantly elevated levels of carcinoembryonic antigen are commonly associated with (lung) carcinomas but rarely with mesotheliomas. Thus, together with identification of the antigen in serum, pleural fluid, or ascitic fluid, immunohistochemical and immunocytochemical techniques for detecting carcinoembryonic antigen provide a valuable aid for distinguishing malignant mesothelioma from metastatic carcinomas.
Diphenylhydantoin-induced hypogammaglobulinemia in a patient infected with human immunodeficiency virus. A case is reported of reversible panhypogammaglobulinemia in a human immunodeficiency virus (HIV)-infected patient. Onset and resolution were temporally correlated with initiation and termination, respectively, of diphenylhydantoin therapy for a possible seizure. A rapid alteration in peripheral T-cell subpopulations was also noted in association with diphenylhydantoin administration. This case is compared with previous reports of diphenylhydantoin-associated hypogammaglobulinemia in non-HIV-infected patients. In addition, the case is discussed with regard to possible deleterious effects associated with the use of diphenylhydantoin as therapy for HIV-associated seizures or as an antiretroviral agent in HIV disease.
Effectiveness of growth-promoting therapies. Comparison among growth hormone, clonidine, and levodopa. The ability of growth hormone, clonidine, and levodopa to stimulate growth was compared in short and slowly growing children randomly assigned to different treatment regimens for 6 months. There were 10 children in each group, and 10 additional subjects served as controls. Growth hormone improved mean height velocity, height velocity SD score, and height SD score. The mean height velocity and height velocity SD score were significantly increased by clonidine, while levodopa only enhanced the mean height velocity SD score of the treated children. Moreover, in nine patients (90%) receiving growth hormone, two (20%) receiving clonidine, and one (10%) receiving levodopa, the height velocity was raised by more than 2 cm/y. The increments in height velocity and height SD score were greatest in the growth hormone group. Clonidine induced an increase in height velocity significantly different from that in control children only. In the control group, there was a significant reduction of height SD score with time.
Rhinosporidiosis associated with squamous cell carcinoma in the tongue. The peritumoural region of a squamous cell carcinoma of the tongue when examined with light and electron microscope showed nodular bodies in the submucosa with all the distinctive features of 'sporangium and 'spores' of rhinosporidiosis. The occurrence of rhinosporidiosis in the tongue along with malignancy has not been reported hitherto. Some interesting observations and causal relationships are discussed.
Increasing annual incidence of primary malignant brain tumors in the elderly Between 1973 and 1985, total age-adjusted cancer incidence in the United States (all races, men and women) rose by 10.7%, with an average annual percentage change of +0.9%. Analysis of reported age-specific incidence of primary malignant brain tumors over the same years demonstrates that incidence rates increased dramatically between 1973/1974 and 1985. In 1985, incidence rates for persons aged 75-79, 80-84, and 85 years of age and over were 187%, 394%, and 501%, respectively, of rates in 1973/1974. Similar increases were found in both men and women, analyzed separately and combined. Average annual percentage changes in primary brain tumor incidence were +7.0%, +20.4%, and +23.4% in these age ranges, respectively. Reported incidence in younger persons varied little over the same period of time. The most common histologic type of primary brain tumor in the elderly was of glial origin, predominantly the glioblastoma multiforme and astrocytoma. These tumors are highly malignant and invariably fatal. Two possible causes may explain the increased incidence in the elderly: the introduction and extensive use of x-ray computed tomography since 1973 and/or a true increase in incidence occurring independently of diagnostic advances.
Incidence of cutaneous T cell lymphoma and other rare skin cancers in a defined population. Between 1970 and 1984 in Rochester, Minnesota, rare skin cancers developed in 15 local residents: cutaneous T cell lymphoma (six subjects), dermatofibrosarcoma protuberans (four), adenocarcinoma of sweat glands (two), Merkel cell carcinoma (one), liposarcoma (one), and extramammary Paget's disease (one). These cases were identified through a unique computerized retrieval system that is maintained at the Mayo Clinic for the population of Rochester, Minnesota. The annual incidences of these cancers in the Rochester population were 0.9, 0.5, 0.3, 0.2, 0.2, and 0.2 per 100,000 residents, respectively (standardized to 1980 U.S. population). To our knowledge, this is the first report of the incidences of these rare skin cancers in a well-defined population.
Congenital abnormalities of the lymphatic system: a new clinical classification. The numerous clinical presentations of congenital abnormalities of the lymphatic system in children and the confusing terminology used to describe their pathologic diagnoses impede the physician's understanding of the condition. The clinical classification based on the actual symptoms of the congenital problems we have presented here should help the physician identify the specific abnormality and a potential treatment. Future research should concentrate on the specific causes and the treatment of these congenital abnormalities.
Clinical diagnostic considerations on cocaine abuse. Following a review of the research literature on the psychophysiological effects of cocaine, a study is described of a group of 120 cocaine addicts. Of the 120 patients, 10 (8.33%) exhibited fleeting, unformed, organic delusions and hallucinations. Case reports of the 10 cases are presented. The quality of the adverse subjective effects of cocaine is emphasized, and the differential diagnosis between Cocaine Delusional Disorder and Paranoid Schizophrenia is discussed. Guidelines for a more accurate differential diagnosis are provided.
Risk of cardiovascular mortality in alcohol drinkers, ex-drinkers and nondrinkers. Lower cardiovascular mortality rates in lighter drinkers (versus abstainers or heavier drinkers) in population studies have been substantially due to lower coronary artery disease (CAD) mortality. Controversy about this U-shaped curve focuses on whether alcohol protects against CAD or, because of other traits, whether abstainers are at increased risk. Inclusion of ex-drinkers among abstainers in some studies has led to speculation that this might be the trait increasing the risk of abstainers. This new prospective study among 123,840 persons with 1,002 cardiovascular (600 CAD) deaths showed that ex-drinkers had higher cardiovascular and CAD mortality risks than lifelong abstainers in unadjusted analyses, but not in analyses adjusted for age, gender, race, body mass index, marital status and education. Use of alcohol was associated with higher risk of mortality from hypertension, hemorrhagic stroke and cardiomyopathy, but with lower risk from CAD, occlusive stroke and nonspecific cardiovascular syndromes. Subsets free of baseline cardiovascular or CAD risk had U-shaped alcohol-CAD curves similar to subsets with baseline risk. Among ex-drinkers, maximal past intake and reasons for quitting (medical versus non-medical) were unrelated to cardiovascular or CAD mortality. These data show that: (1) alcohol has disparate relations to cardiovascular conditions; (2) higher cardiovascular mortality rates among ex-drinkers are due to confounding traits related to past alcohol use; and (3) the U-shaped alcohol-CAD relation is not due to selective abstinence by persons at higher risk. The findings indirectly support a protective effect of lighter drinking against CAD.
Chondrosarcoma of the soft tissues. Two different sub-groups. Chondrosarcomas arising from soft tissues are rare. Two different varieties are described, myxoid and mesenchymal. We have collected nine cases of the tumour, five myxoid and four mesenchymal, from a review of 513 cases of chondrosarcoma seen between 1904 and 1988. We report the principal clinical, radiographical and histological differences between the two varieties and discuss their surgical treatment and prognosis.
Can the blood urea nitrogen/creatinine ratio distinguish upper from lower gastrointestinal bleeding? We wanted to know if the blood urea nitrogen to creatinine (BUN/Cr) ratio could help distinguish upper from lower gastrointestinal bleeding. We analyzed retrospectively patients admitted to our hospital for gastrointestinal bleeding over the past 5 years. A total of 126 patients represented 74 upper bleeds and 52 lower bleeds. The mean BUN/Cr ratio was significantly higher in upper than lower bleeders, 34.8 and 17.8 respectively (p less than 0.001). No lower bleeder had a ratio of greater than or equal to 36, whereas 38% of upper bleeders had a ratio of greater than or equal to 36. The BUN/Cr ratio may be an easy, cheap method of distinguishing upper from lower gastrointestinal bleeding in some cases. A BUN/Cr ratio of greater than or equal to 36 suggests upper gastrointestinal bleeding, whereas a ratio of less than 36 is not helpful in locating the source of bleeding.
Controlling stability of a complex movement system. Human movement systems have frequently been treated as one-dimensional, single-axis, rigid bodies in order to simplify the gathering, analysis, and interpretation of data. The problem with this approach is that the results of such assumptions often lead to conclusions about the production and control of movement that do not relate to the control demands placed on the central nervous system. In order to truly understand how the central nervous system plans and produces movements to match environmental demands, we must take into account the many variations available within the body. The purpose of this article is to examine two movement systems that have the potential to act in multiple spatial dimensions with variable muscle action patterns when performing a stabilizing task. Methods of analyzing how the systems operate under differing task constraints and results of the experiments will be presented. Hypothetical models that have been proposed to explain how complex movement systems operate will also be discussed.