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31.
We have recently demonstrated that prothymosin (ProT) when administered intraperitoneally (i.p.) protects DBA/2 mice against the growth of syngeneic leukemic L1210 cells through the induction of tumoricidal peritoneal cells producing high levels of tumor necrosis factor (TNF) [Papanastasiou et al. (1992) Cancer Immunol Immunother 35: 145]. In this report we tested further immunological alterations that may be caused by the administration of ProT in vivo. We demonstrate that i.p. injections of ProT enhance natural killer (NK) cell activity and induce lymphokine-activated (LAK) activity in vivo. Thus, splenocytes from ProT-treated DBA/2 animals exhibited significantly higher cytotoxic activity (up to threefold) against the NK-sensitive YAC cell line and the NK-resistant P815 and L1210 syngeneic tumor cells, as compared to splenocytes from syngeneic control mice. The enhancement of the cytotoxic profile of DBA/2 splenocytes was associated with increased percentages of CD8+ cells, NK cells and activated CD3+ cells. The ProT-induced effect persisted for 30 days after the end of the ProT treatment period and returned to normal levels 20 days later. SPlenocytes from non-treated DBA/2 animals generated high NK and LAK activities in response to ProT in vitro. The ProT-induced NK an LAK activities reached 84% and 75% respectively of what was obtained with interleukin-2 (IL-2). High concentrations of TNF and IL-2 were generated in response to ProT in LAK cultures. These findings suggest that ProT may provide an overall protective effect against tumor growth in vivo through induction of NK and LAK activities possibly indirectly via the production of IL-2 and TNF in the spleen, peritoneal cavity and probably other lymphoid organs.This work was supported by a CEC grant to M. Papamichail  相似文献   
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Indiscriminate discharge of pharmaceutical waste into the aquatic ecosystem may pose serious health challenges to aquatic biota. The effect of acute exposure to ibuprofen was evaluated using changes in behaviour and haematological parameters under static bio-assay method in Clarias gariepinus. Test specimens were exposed to acute concentrations of ibuprofen (0.28, 0.33, 0.38, 0.43 and 0.48 mg l?1) for 24, 48, 72 and 96 h durations respectively. Behavioural and phenotypic changes were observed in surviving fish. There were significant (p < 0.05) concentration and duration-dependent increases in erythrocyte (RBC), haemoglobin (Hb), pack cell volume (PCV) and leukocytes (WBC) in treated fish compared to the control. Insignificant decreases (p > 0.05) in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were observed in treated fish compared to the control. Ibuprofen elicited dose and duration- dependent decrease in neutrophil counts with the decreases being significant (p < 0.05) in the higher doses of 0.43 and 0.48 mg l?1. Ibuprofen did not elicit any significant changes in monocytes, basophils and eosinophils. Changes observed in this study showed that ibuprofen negatively affected the health of the fish and we recommend that discharge of ibuprofen into the aquatic environment should be monitored and controlled.  相似文献   
34.

Background

The main processes in the pathogenesis of cerebral malaria caused by Plasmodium falciparum involved sequestration of parasitized red blood cells and immunopathological responses. Among immune factors, IgG autoantibodies to brain antigens are increased in P. falciparum infected patients and correlate with disease severity in African children. Nevertheless, their role in the pathophysiology of cerebral malaria (CM) is not fully defined. We extended our analysis to an Indian population with genetic backgrounds and endemic and environmental status different from Africa to determine if these autoantibodies could be either a biomarker or a risk factor of developing CM.

Methods/Principal Findings

We investigated the significance of these self-reactive antibodies in clinically well-defined groups of P. falciparum infected patients manifesting mild malaria (MM), severe non-cerebral malaria (SM), or cerebral malaria (CM) and in control subjects from Gondia, a malaria epidemic site in central India using quantitative immunoprinting and multivariate statistical analyses. A two-fold complete-linkage hierarchical clustering allows classifying the different patient groups and to distinguish the CM from the others on the basis of their profile of IgG reactivity to brain proteins defined by PANAMA Blot. We identified beta tubulin III (TBB3) as a novel discriminant brain antigen in the prevalence of CM. In addition, circulating IgG from CM patients highly react with recombinant TBB3. Overall, correspondence analyses based on singular value decomposition show a strong correlation between IgG anti-TBB3 and elevated concentration of cluster-II cytokine (IFNγ, IL1β, TNFα, TGFβ) previously demonstrated to be a predictor of CM in the same population.

Conclusions/Significance

Collectively, these findings validate the relationship between antibody response to brain induced by P. falciparum infection and plasma cytokine patterns with clinical outcome of malaria. They also provide significant insight into the immune mechanisms associated to CM by the identification of TBB3 as a new disease-specific marker and potential therapeutic target.  相似文献   
35.
Zusammenfassung Morphologische Unterschiede zwischen fibrillär-phasischen und afibrillärtonischen Skeletmuskelfasern des Frosches werden elektronenmikroskopisch abgebildet und beschrieben. An Synapsen afibrillär-tonischer Fasern werden neben dem synaptischen Axon sehr viel dünnere para-Axone aufgezeigt. Ihre Bedeutung als leitende Axone der terminaisons en grappes oder als Anteile akzessorischer Fasern in der tonischen Synapse wird diskutiert.Durchgeführt mit Unterstützung durch die Deutsche Forschungsgemeinschaft und das Kultusministerium des Landes Nordrhein-Westfalen.  相似文献   
36.
A new method is described for the purification of the intermediate filament protein vimentin from Ehrlich ascites tumor cells using single-stranded DNA-cellulose affinity chromatography. The procedure is rapid and allows the large scale isolation of the protein. Partial characterization of vimentin shows that it has a molecular weight of 58000 and an apparent pI of 5.3. It can be degraded by the vimentin-specific, Ca2+-activated proteinase which results in the production of a characteristic set of degradation products. The vimentin also cross-reacts with the intermediate filament protein monoclonal antibody, α-IFA.  相似文献   
37.
Noninvasive diagnosis of atherosclerosis via single biomarkers has been attempted but remains elusive. However, a previous polymarker or pattern approach of urine polypeptides in humans reflected coronary artery disease with high accuracy. The aim of the current study is to use urine proteomics in ApoE(-/-) mice to discover proteins with pathophysiological roles in atherogenesis and to identify urinary polypeptide patterns reflecting early stages of atherosclerosis. Urine of ApoE(-/-) mice either on high fat diet (HFD) or chow diet was collected over 12 weeks; urine of wild type mice on HFD was used to exclude diet-related proteome changes. Capillary electrophoresis coupled to mass spectrometry (CE-MS) of samples identified 16 polypeptides specific for ApoE(-/-) mice on HFD. In a blinded test set, these polypeptides allowed identification of atherosclerosis at a sensitivity of 90% and specificity of 100%, as well as monitoring of disease progression. Sequencing of the discovered polypeptides identified fragments of α(1)-antitrypsin, epidermal growth factor (EGF), kidney androgen-regulated protein, and collagen. Using immunohistochemistry, α(1)-antitrypsin, EGF, and collagen type I were shown to be highly expressed in atherosclerotic plaques of ApoE(-/-) mice on HFD. Urinary excretion levels of collagen and α(1)-antitrypsin fragments also significantly correlated with intraplaque collagen and α(1)-antitrypsin content, mirroring plaque protein expression in the urine proteome. To provide further confirmation that the newly identified proteins are relevant in humans, the presence of collagen type I, α(1)-antitrypsin, and EGF was also confirmed in human atherosclerotic disease. Urine proteome analysis in mice exemplifies the potential of a novel multimarker approach for the noninvasive detection of atherosclerosis and monitoring of disease progression. Furthermore, this approach represents a novel discovery tool for the identification of proteins relevant in murine and human atherosclerosis and thus also defines potential novel therapeutic targets.  相似文献   
38.
39.
Expected future cellulosic ethanol production increases the demand for biomass in the US Corn Belt. With low nutritious value, low nitrogen content, and compact biomass, maize cobs can provide a significant amount of cellulosic materials. The value of maize cobs depends on cob architecture, chemical composition, and their relation to grain yield as primary trait. Eight traits including cob volume, fractional diameters, length, weight, tissue density, and grain yield have been analyzed in this quantitative trait locus (QTL) mapping experiment to evaluate their inheritance and inter-relations. One hundred eighty-four recombinant inbred lines of the intermated B73?×?Mo17 (IBM) Syn 4 population were evaluated from an experiment carried out at three locations and analyzed using genotypic information of 1,339 public SNP markers. QTL detection was performed using (1) comparison-wise thresholds with reselection of cofactors (α?=?0.001) and (2) empirical logarithm of odds score thresholds (P?=?0.05). Several QTL with small genetic effects (R 2?=?2.9–13.4 %) were found, suggesting a complex quantitative inheritance of all traits. Increased cob tissue density was found to add value to the residual without a commensurate negative impact on grain yield and therefore enables for simultaneous selection for cob biomass and grain yield.  相似文献   
40.
Immunization with tumor antigens induces cellular and humoral immune responses. These responses by T cells are specific for defined epitopes (determinants) in the molecule of the immunizing tumor antigen. Extension of such responses to self-antigens requires induction of autoimmunity to the tumor. As with systems of autoimmune disease, expression of T cell autoimmunity is charaterized by diversification of responses from the inducer determinant to other responder (cryptic) determinants. Since similar strategies may be useful for therapy of human cancers, we investigated whether the induction of response to a HER-2 peptide F7 (776–789) induces enhanced reactivity of other HER-2 peptides. We found that stimulation with F7 can expand a response to another epitope F13 (884–899) in both an ovarian cancer patient with progressive disease and a healthy donor who shared HLA-DR11. This response was characterized mainly by increased interferon γ secretion, and proliferation, but was not observed with another donor who shared HLA-DR14 and HLA-DQ5 with the patient. Since repeated vaccination with the same epitope may lead to a decline of primary cell reactivity caused by apoptosis spreading the response to other epitopes, the tumor antigen may provide an approach for maintaining an inflammatory Th1 response during cancer vaccination. Received: 10 April 2000 / Accepted: 12 July 2000  相似文献   
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