Lipid peroxidation, occupational stress and aging in workers of a prehospital emergency service.

BACKGROUND: Stressful conditions lead to formation of excessive free radicals, and lipid peroxidation is one of the major outcomes of free radical-mediated injury that directly damages membranes and generates a number of secondary products. OBJECTIVES: To determine the levels of malondialdehyde, an end product of lipid peroxidation, according to demographic and occupational variables in workers of a prehospital emergency service and to analyse the relationship between malondialdehyde levels and burnout. MATERIAL AND METHODS: One hundred and eleven healthy workers of a prehospital emergency service and eighty aged-matched healthy individuals of both sexes as a control group were surveyed. Malondialdehyde levels were measured by the Bull and Marnett method. To measure burnout, the Maslach Burnout Inventory was used. RESULTS: Professional category is associated with lipid peroxidation and burnout levels (Malondialdehyde levels were: physicians 338.10+/-14.47, nurses 329.17+/-12.62 and technicians 296.74+/-14.28; burnout levels were: physicians 41.29+/-3.59, nurses 37.38+/-6.05 and technicians 35.33+/-5.87). Working at night and in the evening increased malondialdehyde and burnout levels. Malondialdehyde levels increase with age. No significant variations with respect to sex were detected. Significant variations in malondialdehyde levels were detected between singles (303.13+/-12.74) and married people (344.43+/-13.43) but not with respect to divorcees (326.44+/-11.74). Significant differences were detected in erythrocyte malondialdehyde levels between smokers (341.37+/-17.09) and nonsmokers (302.21+/-12.38), but not for alcohol consumption. CONCLUSIONS: These findings suggest a positive correlation between malondialdehyde, a biomarker of lipid peroxidation and occupational stress, as estimated by elements of the Maslach Burnout Inventory, and oxidative stress.     

Partial Portal Vein Ligation Plus Thioacetamide: A Method to Obtain a New Model of Cirrhosis and Chronic Portal Hypertension in the Rat

To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations.     

用混合粘合剂碳糊电极测定丁螺环酮

用混合粘合剂碳糊电极测定丁螺环酮张正奇，曾鸽鸣，刘传桂，黎艳飞（湖南大学化学化工系，长沙４１００８２）碳糊电极无毒，制作方便，表面更新容易，应用电位范围广，在药物分析中已有应用［１～５］。我们在液体石腊中加入添加剂，组成混合粘合剂，可显著改善电极的检...     

Viral infections in the mouth

Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.     

SEOM clinical guidelines for the treatment of follicular non-Hodgkin’s lymphoma

Follicular lymphoma (FL) is the second most common subtype of non-Hodgkin’s lymphoma (NHL) in the Western world. FL constitutes the most frequent indolent lymphoma, well characterized by its clinical presentation related to nodal involvement and its morphologic and biologic features. It is often managed as an incurable disease. However, several active therapeutic approaches from the ‘wait and watch” strategy to the allogeneic transplantation are available for management of patients with FL and clearly have changed the natural history of this disease, achieving a long-term disease-free survival. Therapeutic decision is mostly conditioned by patient’s characteristics, stage, histological grade, tumor burden, and risk-predicting factors. This article try to summarizes the diagnosis and treatment of this heterogeneous group of patients.     

Isolation and characterization of subgenomic DNAs encapsidated in "single" T = 1 isometric particles of Maize streak virus

"Single" T = 1 isometric particles of Maize streak virus (MSV) have been isolated from infected maize leaves. Biochemical and genetic characterizations show that these particles contain subgenomic (sg) MSV DNA encapsidated by the MSV coat protein. The largest sg DNA is 1.56 kb, slightly larger than half genome size, although sg DNAs as small as 0.2 kb were also cloned. The sg DNAs are not infectious, and they do not appear to play a role in the pathogenicity of MSV. This is the first report of sg DNAs for MSV and, to our knowledge, the first time that encapsidated sg DNAs have been characterized at the sequence level for any geminivirus. These data will assist in our investigations into the role of genomic DNA in the formation of the unique geminate capsid architecture of the Geminiviridae.     

The measurement of transforming growth factor type beta (TGF beta) levels produced by peripheral blood mononuclear cells requires the efficient elimination of contaminating platelets.

In recent years there has been an increasing interest in measuring the levels of TGF beta produced by peripheral blood mononuclear cells (PBMC), since its abnormal regulation seems to be involved in several pathological states. Platelet-contamination, a common feature in PBMC populations isolated by the standard Ficoll-Paque method, would theoretically disturb the measurement of the levels of TGF beta produced by mononuclear cells, since platelets represent an important source of this cytokine. In this study, supernatants of PBMC cultures from healthy subjects, either platelet-contaminated or uncontaminated, were assayed for TGF beta activity in three different bioassays. We report that the presence of platelets led in most cases to an important overestimation of the TGF beta levels produced by MNC in the Swiss-3T3 bioassay and in a PBMC proliferation assay. In contrast, in the Mv1Lu bioassay these levels were significantly underestimated, an effect which we attribute to the presence of other platelet-derived growth factors. These results suggest that the elimination of platelets from PBMC cultures is essential if TGF beta production by mononuclear cells is to be studied.