BPA暴露对本体和子代胰岛β细胞转录组差异对比分析

双酚A(BPA)作为一种典型的环境内分泌干扰物,与二型糖尿病和肥胖症等代谢类疾病密切相关.在这项研究中,旨在探讨BPA直接暴露以及围产期暴露对本体和子代胰岛β细胞影响的差异,从而实现对不同易感人群的精准预防与治疗.通过对GEO数据库中GSE126297和GSE82175两个数据集进行分析,共筛选出108个共有的差异基因...     

Selective effects of fenitrothion on murine splenic T-lymphocyte populations and cytokine/granzyme production

The aim of this study was to investigate in vitro effects of fenitrothion (FNT) on mouse splenic lymphocytes. Here, naïve mice had their spleens harvested and splenocytes isolated. After exposure to FNT for 48 hr: splenocyte viability was measured using a tetrazolium dye assay; cell phenotypes, i.e., B-cells (CD19⁺), T-cells (CD3⁺), and T-cell subsets (CD4⁺ and CD8⁺), were quantified by flow cytometry; and, production of cytokines/granzyme-B was assessed via enzyme-linked immunosorbent assay. The ability for FNT to induce oxidative stress in the cells was evaluated by measuring hydroxyl radical (·OH) and malondialdehyde (MDA) production and changes in glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activity. The results showed that FNT significantly inhibited splenocyte proliferation, and decreased production of interleukin (IL)-2, interferon gamma, IL-4, and granzyme B, but had no impact on IL-6 production. FNT also selectively decreased splenic T-cell levels but did not induce changes in CD19⁺ B-cells. Further, within the T-cell populations, percentages of CD3⁺, CD4⁺, and CD8⁺ T-cells (particularly CD8⁺ T-cells) were reduced. Lastly, FNT selectively increased MDA and ·OH production and inhibited SOD and GSH-Px activities in the splenic lymphocytes. These findings suggest that, due to oxidative damage, FNT selectively inhibits splenic T-lymphocyte survival and cytokine/granzyme production in vitro.     

固定化细胞技术及应用于废水处理的最新进展

本文简要介绍了用于废水处理的固定化细胞技术及应用此技术进行废水处理的七个领域的最新成就。     

Detection of fetal cells in maternal blood

We report the detection of fetal cells in the maternal circulation by enzymatic amplification of a single copy gene sequence that was fetal-specific. Fetal HLA-A2-positive cells were sorted from maternal HLA-A2-negative cells by flow cytometry and confirmed by demonstration of a fetal-specific HLA-DR4 sequence. However, this sequence could not be detected in unenriched maternal DNA prepared at 28 and 32 weeks' gestation. The sensitivity of detection was 1 HLA-DR4-positive cell in 10⁵ HLA-DR4-negative cells. We conclude that prenatal diagnosis of paternally inherited autosomal-dominant genetic defects may be possible by selective gene amplification of maternal peripheral blood. However, preliminary enrichment for fetal cells may be necessary.     

The time of appearance and disappearance of fetal DNA from the maternal circulation

A single copy Y-chromosome DNA sequence was amplified using the polymerase chain reaction (PCR) from the peripheral blood of 30 women who had achieved a pregnancy through an in vitro fertilization (IVF) programme. The time of conception was known precisely and was confirmed by serial ultrasound scans. Conceptions were dated as the number of weeks after fertilization plus 2, to give a time equivalent to the obstetric menstrual dating of the pregnancy (LMP). Y-chromosome-specific DNA was detected in all pregnancies with a male fetus (18/30). The earliest detection was at 4 weeks and 5 days, and the latest at 7 weeks and 1 day. Y-chromosome-specific sequences were no longer detected in any of the male pregnancies 8 weeks after delivery. No Y-chromosome sequences were detected in any of the pregnancies where only female babies were delivered. This demonstrates that fetal DNA appears in the maternal circulation early in the first trimester, that it can be identified in all pregnancies tested by 7 weeks, that it continues to be present throughout pregnancy, and that it has been cleared from the maternal circulation 2 months after parturition. Early non-invasive prenatal diagnosis for aneuploidies and inherited disorders will be possible in all pregnancies if fetal cells can be isolated free from maternal contamination (or identified accurately in the presence of maternal cells) without problems of contamination from previous pregnancies.     

裂变产物170Tm的体内蓄积特性诱发骨髓细胞突变效应研究

对裂变产物~(170)Tm的体内蓄积特性和诱发细胞突变效应的监测结果表明,当机体摄入~(170)Tm后,在短时间内即能迅速进入并滞留于骨组织中,其滞留量占体内各器官组织中的首位呈现高度选择性亲骨特征,在机体摄入~(170)Tm后的不同阶段,骨组织中的累积吸收剂量随着观察时间的延长而增升,其诱发骨髓细胞的染色体畸变率亦相应增高。由~(170)Tm内污染所诱发的染色体结构异常为染色单体型畸变,其中主要为染色单体断裂。随着骨组织中累积吸收剂量的增升,可观察到在一个细胞中同时有两个畸变发生,也诱发个别的染色体易位。     

The oxidation of octanoic acid by cultured amniotic fluid cells: The effect of cell type and passage number

We have measured the rate of oxidation of [1⁻¹⁴C]octanoate in cultured amniotic fluid (AF) cells at various passages and in AF cell lines with different clonal morphology. It is possible that both the passage number and the cell type may influence the outcome of prenatal diagnosis of fatty acid oxidation defects using this technique. We found that there was no significant difference between the three major AF cell types (epithelial, large epithelial, and fibroblast) when analysed at identical passage number but there was a significant reduction in octanoate oxidation in all cell types with increasing passage. For reliable prenatal diagnosis, cell lines of similar low passage number should be used.     

Mosaic trisomy 17 in amniotic fluid cells not confirmed in the newborn

A case of true fetal mosaicism 46,XY/47,XY, + 17 was diagnosed in amniotic fluid cells. After genetic counselling and unsuccessful periumbilical blood sampling the pregnancy continued to term, and a healthy male infant was born. Lymphocytes of the newborn had a normal karyotype. Follow-up of the child at age 18 months showed normal physical and mental development indicating that the trisomic cell line was restricted most probably to the extra fetal tissue.     

Cross-hybridization of the chromosome 13/21 alpha satellite DNA probe to chromosome 22 in the prenatal screening of common chromosomal aneuploidies by fish

In a routine application of commercially available centromeric DNA probes for the prenatal screening of common trisomies involving the autosomes 13, 18, and 21, and sex chromosomes, four cases of discrepancy between fluorescence in situ hybridization (FISH) results and follow-up cytogenetic analysis were observed from a total of 516 cases of amniocentesis. In three of these cases, the results were false negative, and in one false positive. In this case, amniocentesis was performed because of a positive triple test in a 34-year-old woman with previous infertility treatment. The alpha satellite DNA probe for chromosomes 13/21 revealed five signals in 50 per cent of uncultured amniocytes, while standard cytogenetic analysis showed a normal karyotype. FISH analysis on metaphase chromosomes demonstrated the location of the additional signal in the centromeric region of chromosome 22. This additional signal was also present in the centromeric region of chromosome 22 of the mother, providing evidence for a possible inherited polymorphism in chromosome 22 responsible for unspecific hybridization with the alpha satellite probe for chromosomes 13/21 in this case. The observed polymorphism in centromeric regions may contribute to unreliability of the use of the 13/21 alpha satellite probe for prenatal screening by FISH.     

包埋固定化微生物法处理含油废水研究

本研究通过包埋固定化微生物法固定除油菌（Y1’菌），用于处理含油废水，并以水体中乳化油去除率为指标考察了影响乳化油降解的各种因素。选用聚乙烯醇（PVA）-海藻酸钠（SA）复配作为包埋固定化载体材料，制备成固定化微生物小球（IMB），通过实验优化了IMB制备的工艺条件。连续批次除油实验结果表明，在25-40℃，固液比1：10，HRT为6h的条件下，进水油含量在20—50mg／L，乳化油去除率可达85％-90％，出水油含量低于5mg／L。