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Negative Individuals (negative + individual)
Selected AbstractsBoredom in the workplace: More than monotonous tasksINTERNATIONAL JOURNAL OF MANAGEMENT REVIEWS, Issue 4 2009Lia Loukidou Boredom is an emotional state that has a long history in organizational research. Despite recent changes in technology and the organization of work, boredom remains a part of the experience of work. The available evidence indicates that boredom is associated mainly with negative individual and organizational outcomes. The authors organize the review of the antecedents of boredom around four major themes in the literature: boredom in relation to jobs; individual differences; social context; and goals and coping. The authors conclude that the major challenge for researchers is to provide an integrative account of boredom which subsumes multiple areas of research, and that one most promising avenue for future research requires further attention to boredom in relation to coping processes, pursuit and attainment of personal goals. [source] Natural Killer Cell Receptor+ T-Lymphocytes in Normal and Helicobacter pylori -Infected Human Gastric MucosaHELICOBACTER, Issue 6 2008Joan O'Keeffe Abstract Background:,Helicobacter pylori infection is associated with development of chronic inflammation and infiltration of immune cells into the gastric mucosa. As unconventional T-lymphocytes expressing natural killer cell receptors are considered to play central roles in the immune response against infection, a study investigating their frequencies in normal and H. pylori -infected gastric mucosa was undertaken. Materials and Methods:, Flow cytometry was used to quantify T-cells expressing the natural killer cell markers CD161, CD56, and CD94 in freshly isolated lymphocytes from the epithelial and lamina propria layers of gastric mucosa. Thirteen H. pylori -positive and 24 H. pylori -negative individuals were studied. Results:, CD94+ T-cells were the most abundant (up to 40%) natural killer receptor-positive T-cell population in epithelial and lamina propria layers of H. pylori -negative gastric mucosa. CD161+ T-cells accounted for about one-third of all T-cells in both compartments, but the lowest proportion were of CD56+ T-cells. Compared with H. pylori -negative mucosa, in H. pylori -infected mucosa the numbers of CD161+ T-cells were significantly greater (p = .04) in the epithelium, whereas the numbers of CD56+ T-cells were lower (p = .01) in the lamina propria. A minor population (< 2%) of T-cells in both mucosal layers of H. pylori -negative subjects were natural killer T-cells, and whose proportions were not significantly different (p > .05) to those in H. pylori -infected individuals. Conclusions:, The predominance, heterogeneity, and distribution of natural killer cell receptor-positive T-cells at different locations within the gastric mucosa reflects a potential functional role during H. pylori infection and warrants further investigation. [source] Effectiveness of hepatitis C treatment with pegylated interferon and ribavirin in urban minority patients,HEPATOLOGY, Issue 4 2010Paul Feuerstadt Randomized controlled trials of hepatitis C virus (HCV) therapy with pegylated interferon and ribavirin have demonstrated sustained viral response rates (SVRs) of 54%-63% (efficacy). Treatment results in clinical practice (effectiveness) may not be equivalent. The goal of this study was to assess the effectiveness of HCV treatment with pegylated interferon and ribavirin in a treatment-naïve, human immunodeficiency virus (HIV)-negative, United States urban population with many ethnic minority patients. We evaluated 2,370 outpatients for HCV therapy from 2001 to 2006 in the Faculty Practice of the Albert Einstein College of Medicine or the attending-supervised Montefiore Medical Center Liver Clinic. Care was supervised by one experienced physician under conditions of everyday clinical practice, and appropriate ancillary resources were made available to all patients. Two hundred fifty-five patients were treated with a mean age of 50 years (60% male, 40% female; 58% Hispanic, 20% African American, 9% Caucasian, 13% other; 68% genotype 1, the remainder genotypes 2 or 3). Patients had at least one liver biopsy. Intention-to-treat analysis (ITT) showed SVR in 14% of genotype 1 patients and 37% in genotype 2/3 patients (P < 0.001). SVR was significantly higher in faculty practice (27%) than in clinic patients (15%) by intention-to-treat (P = 0.01) but not per-protocol analysis (46% faculty practice, 34% clinic). 3.3% of 1,656 treatment-naïve, HIV antibody,negative individuals ultimately achieved SVR. Current hepatitis C therapies may sometimes be unavailable to, inappropriate for, and ineffective in United States urban patients. Treatment with pegylated interferon and ribavirin was less effective in this population than is implied by multinational phase III controlled trials. New strategies are needed to care for such patients. (HEPATOLOGY 2010.) [source] Intrahepatic hepatitis C viral RNA status of serum polymerase chain reaction,negative individuals with histological changes on liver biopsyHEPATOLOGY, Issue 6 2001Sharon Barrett For individuals testing anti-HCV positive but negative for HCV RNA in serum, diagnosis remains unclear. Debate exists over whether these individuals have resolved infection or have similar clinical, histological, and virological profiles as serum PCR,positive individuals. The aim of this study was to assess the significance of histological changes in the liver of 33 serum PCR,negative women by investigation of clinical, histological, and intrahepatic HCV RNA status. For comparison, clinical and histological data from 100 serum PCR,positive women is presented. Viral RNA status was determined in snap-frozen liver biopsies using a sensitive nested PCR with an internal control. Although serum PCR,positive and ,negative individuals shared similar age at diagnosis, source, and duration of infection, they differed from a clinical, histological, and virological perspective. Mean serum ALT levels were significantly lower in serum PCR,negative women (27.4 IU/L ± 18 vs. 58.7 IU/L ± 40 P < .001). Similarly, although inflammation (82%) and mild fibrosis (15%) were observed in PCR,negative biopsies, the mean HAI/fibrosis scores were significantly lower than in serum PCR,positive biopsies (1.9 ± 1.5/0.15 ± 0.4 vs. 4.2 ± 1.4/1.1 ± 1.3, respectively). Finally, HCV RNA was not detectable in serum PCR,negative liver biopsies but was detectable in all serum PCR,positive control biopsies. In conclusion, serum PCR,negative individuals may have mild histological abnormalities more suggestive of nonspecific reactive changes, steatosis or nonalcoholic steatohepatitis rather than chronic HCV, even when significant antibody responses are present in serum. Negative serum PCR status appears to reflect cleared past-exposure in liver. [source] Blood group antigens and immune responses,detailed knowledge is necessary to prevent immunization and to follow up immunized individualsISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue n1 2010A. Husebekk Background The immune system is educated to detect and react with foreign antigens and to tolerate self-antigen. Transfusion of blood cells and plasma and pregnancies challenge the immune system by the introduction of foreign antigens. The antigens may cause an immune response, but in many instances this is not the case and the individual is not immunised after exposure of blood group antigens. Aims The aim of the presentation is to dissect some immune responses to blood group antigens in order to understand the mechanism of immunisation. Methods The results of immune responses to blood group antigens can be detected by the presence of antibodies to the antigens. If the antibodies are of IgG class, the activated B cells have received help from antigen specific T cells. Both antibodies, B cells and T cells can be isolated from immunised individuals and studied in the laboratory. Also B-cell receptors and T-cell receptors as well as MHC molecules on antigen presenting cells can be studied and models of the immune synapses can be created in vitro. Results The most classic immune responses in transfusion medicine and in incompatible pregnancies are immune responses to the RhD antigen on red cells, HLA class I molecules on white cells and platelets and human platelet antigens. The nature of these antigens are different; RhD antigens are part of a large complex, present on red cells from RhD positive individuals and completely lacking on red cells from RhD negative individuals. It is likely that many peptides derived from this antigen complex may stimulate T cells and B cells. HLA antigens are highly polymorphic and the antigens are known to induce strong alloimmune responses. The HPA antigens are created by one amino acid difference in allotypes based on a single nucleotide polymorphism at the genetic level. HPA 1a induce immune responses in 10% of HPA 1b homozygote pregnant women. The result of these immune responses is destruction of blood cells with clinical consequences connected to the effect of transfusions or the outcome of pregnancies. Summary/Conclusions Even though there is emerging knowledge about the immune responses to some of the blood group antigens, more information must be gained in order to understand the complete picture. The action of the innate immune response initiating the adaptive immune response to blood group antigens is not well understood. A detailed understanding of both the innate ad the adaptive part of the immune response is necessary to identify individuals at risk for immunisation and to prevent immunisation to blood group antigens. [source] Management measures to control a feline leukemia virus outbreak in the endangered Iberian lynxANIMAL CONSERVATION, Issue 3 2009G. López Abstract The feline leukemia virus (FeLV) is a retrovirus that affects domestic cats all over the world. Its pathogenic effects generally include anemia, immunosuppression or tumors. Dissemination over populations is linked to cat sociality, because the virus is transmitted by direct contact. Although the domestic cat is its common host, FeLV infection has also been described in some wild felids. In the Iberian lynx Lynx pardinus, some sporadic FeLV infection cases have been reported since 1994, but an outbreak with the involvement of several animals has never been described until now. During spring 2007, an FeLV outbreak hit the Doñana (SW Spain) population. The infection rapidly spread throughout the densest subpopulation throughout Doñana. Infected animals showed very acute anemic disease, most of them dying in <6 months. To avoid FeLV dissemination, a control program was carried out that included removal of viremic lynxes, vaccination of negative individuals and reduction of the feral cat population. The program was implemented both in Doñana and in Sierra Morena populations. In Doñana, around 80% of the total lynx population and 90% of the outbreak focus subpopulation were evaluated. Seven out of the 12 infected individuals found died and two reverted to latency; the remaining viremic animals have been kept in captivity. The outbreak appears to have been successfully confined to the subpopulation where the virus appeared and no more cases have been found since August 2007. In the larger Sierra Morena population, 8% of the lynx population was surveyed. Thirty-four uninfected Iberian lynxes were vaccinated at least once. The FeLV prevalence was found to be 27% in the Doñana population and 0% in the Sierra Morena population. [source] | ||||||||||