中国人群遗传结构分析

本文根据红细胞血型基因频率,用Harpending和Jenkins(1973)方法计算了中国22个人群间的遗传距离,同时在国内首次运用主坐标分析及其排序方法展示了中华民族的遗传结构,反映出中国东西人群与南北人群间的基因流。     

骨髓间充质干细胞对肾移植受者T淋巴细胞分化和miRNA-155表达的影响

目的探讨骨髓间充质干细胞（MSCs）对肾移植受者T淋巴细胞分化和miRNA-155表达的影响。 方法选取2013年1月至2017年12月于福州总医院接受MSCs诱导+同种异体肾移植术的受者20例（MSCs组）,对照组为同期配对的异体肾移植受者20例。两组患者术后免疫抑制方案均为霉酚酸酯+他克莫司+强的松。两组患者分别于移植术前、术后第15天抽取静脉血,流式细胞仪检测外周血CD4⁺ CD25⁺ FoxP3⁺ Treg细胞/?CD4⁺细胞亚群比值;ELISA检测白细胞介素2（IL-2）、肿瘤坏死因子α（TNF-α）和白细胞介素10（IL-10）浓度;免疫磁珠分选外周血T淋巴细胞后,Rea1-time PCR法检测外周血T淋巴细胞中miRNA-?155的表达。两组间均数比较采用独立t检验,治疗前后均数比较采用配对t检验。 结果移植前两组肾移植受者外周血CD4⁺ CD25⁺ FoxP3⁺ Treg细胞/?CD4⁺细胞比值、IL-2、IL-?10、TNF-α、T淋巴细胞miRNA-155表达水平差异均无统计学意义（P均> 0.05）;术后第15天,与对照组相比,MSCs组外周血CD4⁺ CD25⁺ FoxP3⁺ Treg细胞/?CD4⁺细胞亚群比值（30.44﹪?± 4.23﹪? vs 26.06﹪?±4.77﹪,t = 2.365,P = 0.042）、IL-10水平（20.35?ng/?L?±?5.10?ng/?L? vs 16.63?ng/?L±6.26?ng/?L,t = 2.062,P?=?0.046）上升,而IL-2（27.47ng/?L±4.30 ng/?L vs 31.40?ng/?L±5.33 ng/L,t = 2.252,P = 0.015）、TNF-α（41.52?ng/?L±8.32?ng/L vs 46.67?ng/?L±6.71?ng/L,t = 2.157,P = 0.037）和T淋巴细胞miRNA-155表达水平（1.61±0.31 vs 1.89±0.15,t = 3.688,P?= 0.001）则降低。 结论MSCs能够升高肾移植受者外周血CD4⁺ CD25⁺ FoxP3⁺ Treg细胞/?CD4⁺细胞比值和IL-10水平,降低IL-2、TNF-α和T淋巴细胞miRNA-155表达水平,与MSCs的免疫耐受诱导有关。     

国内生物基材料产业发展现状

近年来,生物基材料正逐步成为引领当代世界科技创新和经济发展的又一新的主导产业。文章综述了国内生物基材料产业的最新进展,对整个生物基材料产业市场进行了综合分析,包括生物基化学品如乳酸、1,3-丙二醇、丁二酸等,可生物降解生物基塑料如二元酸二元醇共聚酯、聚乳酸、二氧化碳共聚物、聚羟基烷酸酯、聚己内酯、热塑性生物质塑料,非生物降解生物基塑料如生物基聚酰胺、聚对苯二甲酸丙二醇酯、生物基聚氨酯,以及生物基纤维等材料的产业现状。     

An Exploratory Study of the Association between KCNB1 rs1051295 and Type 2 Diabetes and Its Related Traits in Chinese Han Population

Since the KCNB1 encoding Kv2.1 channel accounts for the majority of Kv currents modulating insulin secretion by pancreatic islet beta-cells, we postulated that KCNB1 is a plausible candidate gene for genetic variation contributing to the variable compensatory secretory function of beta-cells in type-2 diabetes (T2D). We conducted two studies, a case-control study and a cross-section study, to investigate the association of common single-nucleotide polymorphisms (SNPs) in KCNB1 with T2D and its linking traits. In the case-control study, we first examined the association of 20 tag SNPs of KCNB1 with T2D in a population with 226 T2D patients and non-diabetic subjects (screening study). We then identified the association in an enlarged population of 412 T2D patients and non-diabetic subjects (replication study). In the cross-sectional study, we investigated the linkage between the candidate SNP rs1051295 and T2D by comparing beta-cell function and insulin sensitivity among rs1051295 genotypes in a general population of 1051 subjects at fasting and after glucose loading (oral glucose tolerance tests, OGTT) in 84 fasting glucose impaired subjects, and several T2D-related traits. We found that among the 19 available tag SNPs, only the KCNB1 rs1051295 was associated with T2D (P = 0.027), with the rs1051295 TT genotype associated with an increased risk of T2D compared with genotypes CC (P = 0.009). At fasting, rs1051295 genotype TT was associated with a 9.8% reduction in insulin sensitivity compared to CC (P = 0.008); along with increased plasma triglycerides (TG) levels (TT/CC: P = 0.046) and increased waist/hip (W/H) ratio (TT/CC: P = 0.013; TT/TC: P = 0.002). OGTT confirmed that genotype TT exhibited reduced insulin sensitivity by 16.3% (P = 0.030) compared with genotype TC+CC in a fasting glucose impaired population. The KCNB1 rs1051295 genotype TT in the Chinese Han population is associated with decreased insulin sensitivity and increased plasma TG and W/H ratio, which together contribute to an increased risk for T2D.     

华南虎血液及生物化学某些指标的测定

用血液及生物化学的常规测定方法对６１例华南虎的血液常规,３０余例血液生化指标进行了分析测定,经生物学统计获得了华南虎的血液和生物化学的参考值。     

Characterization of Conformation-dependent Prion Protein Epitopes

Whereas prion replication involves structural rearrangement of cellular prion protein (PrP^C), the existence of conformational epitopes remains speculative and controversial, and PrP transformation is monitored by immunoblot detection of PrP(27–30), a protease-resistant counterpart of the pathogenic scrapie form (PrP^Sc) of PrP. We now describe the involvement of specific amino acids in conformational determinants of novel monoclonal antibodies (mAbs) raised against randomly chimeric PrP. Epitope recognition of two mAbs depended on polymorphisms controlling disease susceptibility. Detection by one, referred to as PRC5, required alanine and asparagine at discontinuous mouse PrP residues 132 and 158, which acquire proximity when residues 126–218 form a structured globular domain. The discontinuous epitope of glycosylation-dependent mAb PRC7 also mapped within this domain at residues 154 and 185. In accordance with their conformational dependence, tertiary structure perturbations compromised recognition by PRC5, PRC7, as well as previously characterized mAbs whose epitopes also reside in the globular domain, whereas conformation-independent epitopes proximal or distal to this region were refractory to such destabilizing treatments. Our studies also address the paradox of how conformational epitopes remain functional following denaturing treatments and indicate that cellular PrP and PrP(27–30) both renature to a common structure that reconstitutes the globular domain.     

Immunolocalization of steroidogenic enzymes in the fetal, neonatal and adult testis of the shiba goat.

The localizations of steroidogenic enzymes (P450scc, 3betaHSD, P450c17 and P450arom) in testes of Shiba goats were investigated by immunohistochemistry. P450scc, 3betaHSD, P450c17 and P450arom were detected in all Leydig cells of adults. P450scc and P450c17 were observed in most Leydig cells in the fetus (90 days) and neonate (15 days). 3betaHSD and P450arom were found in some Leydig cells of the fetus with weak immunostaining but the numbers of immunopositive Leydig cells and intense immunostaining were increased in Leydig cells of the neonate. These results suggest that Shiba goat testes have the ability to synthesize progestin, androgen and estrogen in the fetus, neonate and adult, and synthesis of these steroid hormones showed an age-related rise.     

Underestimate of PS2 efficiency in the field due to high leaf temperature resulting from leaf clipping and its amendment

Chlorophyll fluorescence parameter F_v/F_m, an indicator of the maximum efficiency of PS2, is routinely measured in the field with plant leaves darkened by leaf clips. I found that on a sunny day of subtropical summer, the F_v/F_m ratio was often underestimated because of a large F₀ value resulted from a high leaf temperature caused by clipping the leaf under high irradiance, especially for long (e.g. 20 min) duration. This phenomenon may overestimate the down-regulation of PS2 efficiency under high irradiance. When leaf temperature was lower than 40 °C, the F₀ level of rice leaves under clipping remained practically unchanged. However, F₀ increased drastically with leaf temperature rising over 40 °C. In most measurements, no significant difference in F_m was found between rice leaves dark-adapted by leaf clips for 10 min and for 20 min. Therefore, shading leaf clips to prevent a drastic increase of leaf temperature, using F₀ measured immediately after the leaf being darkened to calculate F_v/F_m, as well as shortening the duration of leaf clipping are useful means to avoid an underestimate of F_v/F_m.