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1.
A 3-year bacteriological survey of an oyster-growing area in Morocco, where the Japanese oyster (Crassostrea gigas) is grown, showed that the contamination of this lagunar ecosystem was not continuous but intermittent and that animal manure and human recreational activities were important sources of pollution. The major source of contamination was of animal origin, except during the summer, when human contamination prevailed.  相似文献   
2.
We have developed a model for evaluating the integral intercellular interactions in the “endotheliocyte‐neutrophil” system and have shown the high variability of adhesion contacts in different donors associated with different expression profiles of neutrophils. Two methods (forсe spectroscopy‐spectroscopy and scanning ion‐conductance microscopy) showed a decrease in the rigidity of the membrane‐cytoskeletal complex of neutrophils under the influence of Staphylococcus aureus 2879 M. Adding this strain to the “endotheliocyte‐neutrophil” system caused a statistically significant decrease in the adhesion force and adhesion work, which indicates a change in the expression profile and physicochemical properties of membranes of both types of interacting cells (neutrophils and endotheliocytes).  相似文献   
3.
In Egypt, β-thalassemia is the most common hereditary hemolytic anemia. Cardiac dysfunction, secondary to iron overload with formation of oxygen free radicals, is the most common cause of death in β-thalassemia patients. This study was designed to determine whether the allelic genotype of apolipoprotein E (Apo E), which exhibits antioxidant properties, could represent a genetic risk factor for the development of left ventricular (LV) dysfunction in β-thalassemia major. Fifty Egyptian β-thalassemia major patients were subjected to echocardiography to assess LV function. Apo E genotyping by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) was done for all patients in addition to 50 age and sex matched healthy control subjects. Patients were classified into three groups. Group I and II were clinically asymptomatic. Group II subjects had evidence of LV dilatation, while Group III patients had clinical and echocardiographic findings of LV failure. Apo E4 allele was significantly higher among Group II and III than in controls. In conclusion, Apo E4 allele can be considered as a genetic risk factor for LV dysfunctions in β-thalassemic patients. It could be used as predictive indicator for additional risk of LV failure, particularly in asymptomatic patients with LV dilatation, requiring a closer follow-up, to prevent further disease progression.  相似文献   
4.
The enantioselective hydrolysis of (R,S)-3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4H-[1,4]benzoxazine (I) with enzymes was investigated. Optically active I and its hydrolyzate, 7,8-difluoro-2,3-dihydro-3-hydroxymethyl-4H-[1,4]benzoxazine (II), are the intermediates for preparing optically active ofloxacins, whose racemate is known to be an excellent antibacterial agent. Lipoprotein lipase from Pseudomonas fluorescens (LPL Amano 3) was found to predominantly hydrolyze (S)-I, giving (R)-I in 54% e.e. and (R)-II in 44% e.e. On the other hand, lipase from Candida cylindracea was found to predominantly hydrolyze (R)-I, giving (S)-I in 24% e.e. and (S)-II in 20% e.e. Since, the optical purities of I and II thus obtained were not particularly high, these optically active I and II were converted into 3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4-(3,5-dinitrobenzoyl)-4H-[1,4]benzoxazine (IV). After recrystallizing IV from ethyl acetate-hexane, (S)- and (R)-II were obtained with high enantiomeric excess by removing the crystallized racemic IV and subsequently hydrolyzing the resulting optically active IV with alkali. The reduction of II afforded 7,8-difluoro-2,3-dihydro-3-methyl-4H-[1,4]benzoxazine (III), for which the optical purity was estimated to be >96%e.e. by HPLC analysis. (R)- and (S)-ofloxacin were prepared from (R)- and (S)-III with retention of their configuration.  相似文献   
5.
The Kv1.3 channel has been widely demonstrated to play crucial roles in the activation and proliferation of T cells, which suggests that selective blockers could serve as potential therapeutics for autoimmune diseases mediated by T cells. We previously described that the toxin mimic FS48 from salivary gland of Xenopsylla cheopis downregulates the secretion of proinflammatory factors by Raw 264.7 cells by blocking the Kv1.3 channel and the subsequent inactivation of the proinflammatory MAPK/NF-κB pathways. However, the effects of FS48 on human T cells and autoimmune diseases are unclear. Here, we described its immunomodulatory effects on human T cells derived from suppression of Kv1.3 channel. Kv1.3 currents in Jurkat T cells were recorded by whole-cell patch-clamp, and Ca2+ influx, cell proliferation, and TNF-α and IL-2 secretion were measured using Fluo-4, CCK-8, and ELISA assays, respectively. The in vivo immunosuppressive activity of FS48 was evaluated with a rat DTH model. We found that FS48 reduced Kv1.3 currents in Jurkat T cells in a concentration-dependent manner with an IC50 value of about 1.42 μM. FS48 also significantly suppressed Kv1.3 protein expression, Ca2+ influx, MAPK/NF-κB/NFATc1 pathway activation, and TNF-α and IL-2 production in activated Jurkat T cells. Finally, we show that FS48 relieved the DTH response in rats. We therefore conclude that FS48 can block the Kv1.3 channel and inhibit human T cell activation, which most likely contributes to its immunomodulatory actions and highlights the great potential of this evolutionary-guided peptide as a drug template in future studies.  相似文献   
6.
Stem and progenitor cells have been identified in many adult tissues including bone marrow, the central nervous system, and skin. While there is direct evidence to indicate the activity of a progenitor cell population in the pituitary gland, this putative subpopulation has not yet been identified. Herein we describe the isolation and characterization of a novel clonogenic cell type in the adult murine pituitary, which we have termed Pituitary Colony-Forming Cells (PCFCs). PCFCs constitute 0.2% of pituitary cells, and generate heterogeneous colonies from single cells. PCFCs exhibit variable proliferative potential, and may exceed 11 population doublings in 14 days. Enrichment of PCFCs to 61.5-fold with 100% recovery can be obtained through the active uptake of the fluorescent dipeptide, beta-Ala-Lys-Nepsilon-AMCA. PCFCs are mostly contained within the large, agranular subpopulation of AMCA+ cells, and constitute 28% of this fraction, corresponding to 140.5-fold enrichment. Interestingly, the AMCA+ population contains rare cells that are GH+ or PRL+. GH+ cells were also identified in PCFC single cell colonies, suggesting that PCFCs have the potential to differentiate into GH+ cells. Together, these data show that the pituitary contains a rare clonogenic population which may correspond to the somatotrope/lactotrope progenitors suggested by previous experiments.  相似文献   
7.

Objective

The decreased expression of muscle-specific microRNA-1 (miR-1) has been found in many cardiovascular diseases and is considered to contribute to heart failure (HF). Here we investigated the role of miR-1 in myocardium protection by infusion of miR-1 in a cardiac global miRNA-deficient mouse.

Methods

We generated a cardiac-selective miRNA-deficient mouse by crossing Dicerflox/flox mice with mice expressing tamoxifen-inducible Cre recombinase under the control of a mouse αMHC promoter. When Dicer gene was removed following tamoxifen injection, the mice were treated with micrONTM mmu-miR-1a-3p agomir (agomir-1). The mice were subjected to echocardiography measurement, and the heart tissue specimens were stained with hematoxylin and eosin (H&E) and Sirius red. Terminal deoxynucleotidyl transferase-mediated dUTP nickend labeling assay and Ki67 immunofluorescence were used to determine apoptosis and proliferation.

Results

Dicer deletion resulted in extensive decrease in cardiac miRNAs in the mice. In echocardiography, the mice developed rapid and dramatic left ventricular enlargement. In histology, apparent cardiomyocyte hypertrophy, myofiber disarray, ventricular fibrosis, inflammatory infiltration, and severe ventricular remodeling were exhibited. When the mice were treated with agomir-1, they did not show any significant abnormalities in heart structure and histology in response to Dicer ablation.

Conclusion

The proper expression of miRNAs plays vital roles in the maintenance of heart histology and function. Among these miRNAs, miR-1 is critical to inhibit myocyte hypertrophy and extracellular matrix deposition, thereby preventing cardiac remodeling in cardiac-selective Dicer deficient mice.  相似文献   
8.
FS2M01.pl,转换片段大小表为0/1矩阵的Perl脚本   总被引:1,自引:0,他引:1  
用Perl语言编写了一个脚本———FS2M01.pl来实现片段大小表向0/1矩阵的转换,解决了由人工方法将遗传图谱的位点信息转换成0/1矩阵的问题。  相似文献   
9.
10.
目的分析连翘酯苷(FS)对小鼠脾脏T和B淋巴细胞增殖、分泌NO和TNF-α的影响,初步探讨其免疫调节作用机制。方法无菌操作分离小鼠脾脏,制备脾脏细胞并用含10%胎牛血清的RPMI 1640培养,在培养液中分别加入刺激剂刀豆蛋白(ConA)和脂多糖(LPS)以及不同浓度40、80、160μg/mL的FS共培养不同时间,采用MTT法检测T和B淋巴细胞的吸光度变化,ELISA和Griess法分别检测细胞分泌TNF-α和NO的水平。结果低浓度和中浓度FS对ConA诱导T淋巴细胞24 h和48 h后细胞增殖和存活率明显提高,诱导时间延长至72 h后FS明显抑制细胞转化;低浓度FS对LPS诱导脾脏B淋巴细胞24 h后细胞增殖和生存率显著提高;FS促进小鼠脾脏T和B淋巴细胞分泌NO;FS促进B淋巴细胞分泌TNF-α,中浓度FS促进T淋巴细胞分泌TNF-α而高浓度反而抑制其分泌。此外,FS对环磷酰胺(CY)处理小鼠的脾脏淋巴细胞体外增殖有明显影响,对细胞NO分泌影响不显著。结论结果提示FS可能通过影响小淋巴细胞增殖和细胞因子分泌而调节免疫细胞功能。  相似文献   
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