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1.
We wanted to assess whether B-cell and/or T-cell responses to collagen and thereby the course of collagen-induced arthritis
could be suppressed by regulatory mechanisms associated with oral tolerance to an unrelated protein. DBA/1 mice were fed ovalbumin
(OVA)-containing pellets ad libitum for 1 week and subsequently coimmunized twice, with a mixture of bovine collagen type
II (BCII) and OVA in Freund's complete adjuvant. Mice fed OVA before coimmunization with BCII and OVA had significantly lower
arthritic scores than mice immunized with BCII only. Their body weight increased during the study period and their anti-BCII
antibody activity was significantly IgG2a lower. The frequency of spleen cells producing IgG anti-BCII antibody was also reduced. Coimmunization per se slightly ameliorated
the development of arthritis, resulting in an early, transient reduction. It resulted in significantly higher IgG1 anti-BCII antibody activity and increased splenocyte secretion of IFN-γ and IL-10 in response to BCII. Our findings demonstrate
that OVA-specific regulatory events induced by feeding OVA, i.e. bystander suppression, reduced the severity of arthritis
in animals immunized with BCII and OVA. Anti-BCII specific antibody responses and cytokine secretion by types 1 and 2 T helper
cells were also decreased. 相似文献
2.
Garba ML Pilcher CD Bingham AL Eron J Frelinger JA 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(5):2247-2254
HIV-infected individuals may progressively lose both HIV-specific and unrelated CTL responses despite the high number of circulating CD8+ T cells. In this study, we report that approximately 25% of HIV+ donors produced TGF-beta(1) in response to stimulation with HIV proteins or peptides. The production of TGF-beta(1) was sufficient to significantly reduce the IFN-gamma response of CD8+ cells to both HIV and vaccinia virus proteins. Ab to TGF-beta reversed the suppression. We found the source of the TGF-beta(1) to be predominantly CD8+ cells. Different peptide pools stimulated TGF-beta(1) and IFN-gamma in the same individual. The TGF-beta(1) secreting cells have distinct peptide specificity from the IFN-gamma producing cells. This represents an important mechanism by which an HIV-specific response can nonspecifically suppress both HIV-specific and unrelated immune responses. 相似文献
3.
B30.2-like domain proteins: update and new insights into a rapidly expanding family of proteins 总被引:5,自引:0,他引:5
Henry J; Mather IH; McDermott MF; Pontarotti P 《Molecular biology and evolution》1998,15(12):1696-1705
The B30.2 domain is a conserved region of around 170 amino acids associated
with several different protein domains, including the immunoglobulin folds
of butyrophilin and the RING finger domain of ret finger protein. We
recently reported several novel members of this family as well as
previously undescribed protein families possessing the B30.2 domain. Many
proteins have subsequently been found to possess this domain, including
pyrin/marenostrin and the midline 1 (MID1) protein. Mutations in the B30.2
domain of pyrin/marenostrin are implicated in familial Mediterranean fever,
and partial loss of the B30.2 domain of MID1 is responsible for Opitz G/BBB
syndrome, characterized by developmental midline defects. In this study, we
scrutinized the available sequence data bases for the identification of
novel B30.2 domain proteins using highly sensitive database-searching
tools. In addition, we discuss the chromosomal localization of genes in the
B30.2 family, since the encoded proteins are likely to be involved in other
forms of periodic fever, autoimmune, and genetic diseases.
相似文献
4.
5.
Serum magnesium concentration was measured in 80 adult patients (age range: 18–40 yr) presenting with acute, uncomplicated
falciparum malaria infection and a control group of 20 age-matched, healthy individuals. The mean serum magnesium concentration in the
patients was 1950.0 ±10.0 μg/dL. The control serum magnesium was 640.0±40.0 μg/dL. This represents an over threefold increase
in serum magnesium levels above normal value, p<0.01. The key pathogenic event in acute falciparum malaria infection is the hemolysis of both infected and uninfected red blood cells. Therefore, the increased serum magnesium
concentration might occur because of the hemolysis arising from erythrocytic merogony because red blood cells contain high
amounts of magnesium. In conclusion, the increased serum magnesium has potential application as a biomarker of acute falciparum malaria infection in adults. 相似文献
6.
Bonnie L. Webster Aiden M. Emery Joanne P. Webster Anouk Gouvras Amadou Garba Oumar Diaw Mohmoudane M. Seye Louis Albert Tchuem Tchuente Christopher Simoonga Joseph Mwanga Charles Lange Curtis Kariuki Khalfan A. Mohammed J. Russell Stothard David Rollinson 《PLoS neglected tropical diseases》2012,6(10)
Background
Schistosomiasis in one of the most prevalent parasitic diseases, affecting millions of people and animals in developing countries. Amongst the human-infective species S. haematobium is one of the most widespread causing urogenital schistosomiasis, a major human health problem across Africa, however in terms of research this human pathogen has been severely neglected.Methodology/Principal Findings
To elucidate the genetic diversity of Schistosoma haematobium, a DNA ‘barcoding’ study was performed on parasite material collected from 41 localities representing 18 countries across Africa and the Indian Ocean Islands. Surprisingly low sequence variation was found within the mitochondrial cytochrome oxidase subunit I (cox1) and the NADH-dehydrogenase subunit 1 snad1). The 61 haplotypes found within 1978 individual samples split into two distinct groups; one (Group 1) that is predominately made up of parasites from the African mainland and the other (Group 2) that is made up of samples exclusively from the Indian Ocean Islands and the neighbouring African coastal regions. Within Group 1 there was a dominance of one particular haplotype (H1) representing 1574 (80%) of the samples analyzed. Population genetic diversity increased in samples collected from the East African coastal regions and the data suggest that there has been movement of parasites between these areas and the Indian Ocean Islands.Conclusions/Significance
The high occurrence of the haplotype (H1) suggests that at some point in the recent evolutionary history of S. haematobium in Africa the population may have passed through a genetic ‘bottleneck’ followed by a population expansion. This study provides novel and extremely interesting insights into the population genetics of S. haematobium on a large geographic scale, which may have consequence for control and monitoring of urogenital schistosomiasis. 相似文献7.
Zilahatou B. Tohon Halima B. Mainassara Amadou Garba Ali E. Mahamane Elisa Bosqué-Oliva Maman-Laminou Ibrahim Jean-Bernard Duchemin Suzanne Chanteau Pascal Boisier 《PLoS neglected tropical diseases》2008,2(5)
Background
In the framework of the monitoring and evaluation of the Nigerien schistosomiasis and soil-transmitted helminth control programme, a follow-up of children took place in eight sentinel sites. The objective of the study was to assess the evolution of Schistosoma haematobium infection and anaemia in schoolchildren after a single administration of praziquantel (PZQ) and albendazole.Methods/Principal Findings
Pre-treatment examination and follow-up at one year post-treatment of schoolchildren aged 7, 8, and 11 years, including interview, urine examination, ultrasound examination of the urinary tract, and measurement of haemoglobin. Before treatment, the overall prevalence of S. heamatobium infection was 75.4% of the 1,642 enrolled children, and 21.8% of children excreted more than 50 eggs/10 ml urine. Prevalence increased with age. The overall prevalence of anaemia (haemoglobin <11.5 g/dl) was 61.6%, decreasing significantly with increasing age. The mean haemoglobinemia was 11 g/dl. In bivariate analysis, anaemia was significantly more frequent in children infected with S. haematobium, although it was not correlated to the intensity of infection. Anaemia was also associated with micro-haematuria and to kidney distensions. In a sub-sample of 636 children tested for P. falciparum infection, anaemia was significantly more frequent in malaria-infected children. In multivariate analysis, significant predictors of anaemia were P. falciparum infection, kidney distension, and the village. One year after a single-dose praziquantel treatment (administered using the WHO PZQ dose pole) co-administered with albendazole (400 mg single dose) for de-worming, the prevalence of S. haematobium infection was 38%, while the prevalence of anaemia fell to 50.4%. The mean haemoglobinemia showed a statistically significant increase of 0.39 g/dl to reach 11.4 g/dl. Anaemia was no longer associated with S. haematobium or to P. falciparum infections, or to haematuria or ultrasound abnormalities of the urinary tract.Conclusions
The high prevalence of anaemia in Nigerien children is clearly a result of many factors and not of schistosomiasis alone. Nevertheless, treatment of schistosomiasis and de-worming were followed by a partial, but significant, reduction of anaemia in schoolchildren, not explainable by any other obvious intervention. 相似文献8.
9.
This investigation assessed the effects of termite mound material (TMM) on the physical properties of sandy soil and on tomato (Solanum lycopersicum L.) growth characteristics and water use efficiency. TMM combined with organic manure, TMM combined with rice straw mulching and organic manure, organic manure alone (OM) and unamended (T0) were the treatments used. Results showed that soil treated with TMM had more clay sized particles and organic carbon content than T0 and OM. In TMM-treated soil, more water was being retained at both field capacity and permanent wilting point. The application of TMM did not affect the amount of plant available water. Saturated hydraulic conductivity also remained unaffected by the TMM application, but increased with the organic matter treatment. Tomatoes grown in TMM amended soils had greater plant height and more leaves, fruit and biomass. No specific rate of TMM application was better for all parameters being assessed. The amount of water used by the tomatoes was significantly correlated (P?<?0.01) with fresh fruit yield (r?=?0.82), leaf area index (r?=?0.82) and total dry matter production (r?=?0.68). While TMM did not specifically affect plant water-use efficiency, this parameter was generally improved in amended soils. 相似文献
10.
Ethical principles guiding public health and genomic medicine are often at odds: whereas public health practice adopts collectivist
principles that emphasize population-based benefits, recent advances in genomic and personalized medicine are grounded in
an individualist ethic that privileges informed consent, and the balancing of individual risk and benefit. Indeed, the attraction
of personalized medicine is the promise it holds out to help individuals get the “right medicine for the right problem at
the right time.” Research biobanks are an effective tool in the genomic medicine toolbox. Biobanking in public health presents
a unique case study to unpack some of these issues in more detail. For example, there is a long history of using banked tissue
obtained under clinical diagnostic conditions for later public health uses. But despite the collectivist approach of public
health, the principles applied to the ethical challenges of biobanking (e.g. informed consent, autonomy, privacy) remain individualist.
We demonstrate the value of using human rights as a public health ethics framework to address this tension in biobanking by
applying it to two illustrative cases. 相似文献