A novel bradykinin-related peptide from skin secretions of toad Bombina maxima and its precursor containing six identical copies of the final product

Amphibian skin contains rich bradykinin-related peptides, but the mode of biosynthesis of these peptides is unknown. In the present study, a novel bradykinin-related peptide, termed bombinakinin M, was purified from skin secretions of the Chinese red bell

Polymerase chain reaction based C4AQ0 and C4BQ0 genotyping: association with systemic lupus erythematosus in southwest Han Chinese

Objective: To investigate the association of complement C4 null genes (C4QO, including C4AQO and C4BQO) and C2 gene with systemic lupus erythematosus (SLE) in southwest Han Chinese; 136 patients with SLE and 174 matched controls were genotyped. Methods: C4 null genes were determined by a polymerase chain reaction (PCR) procedure with sequence specific primers (PCR-SSP). The 2 bp insertion in exon 29, which was previously identified in non-Chinese populations and caused defective C4A genes, was directly typed by sequencing the whole exon 29 using exon specific primers. The exon 6 of complement C2 was also sequenced in both the patients and controls. Results: The frequency of homozygous C4AQO allele was 12.5% (17/136) in patients with SLE compared with 1.1% (2/174) in controls (p<0.001, odds ratio (OR)=12.286, 95% confidence interval (95% CI) 2.786 to 54.170). There was no significant difference for homozygous C4BQO allele between patients with SLE and controls (p=0.699). Patients with the C4AQO gene had an increased risk of acquiring renal disorder, serositis, and anti-dsDNA antibodies compared with those without C4AQO (for renal disorder, p=0.018, OR=8.951, 95% Cl 1.132 to 70.804; for serositis, p=0.011, OR 4.891, 95% CI 1.574 to 15.198; for anti-dsDNA, p=0.004, OR 7.630, 95%Cl 1.636 to 35.584). None of the patients or controls had the 2 bp insertion in exon 29 of the C4 gene. The type I C2 deficiency was not detected in the 3 10 samples. Conclusion: It is suggested that deficiency of C4A (not due to a 2 bp insertion in exon 29), but not C4B or C2, may be a risk factor for acquiring SLE in south west Han Chinese; this results in increased risk of renal disorder, serositis, and anti-dsDNA antibodies in patients with SLE. Racial differences seem to be relevant in susceptibility to SLE.

吗啡对猕猴瞳孔光反应能力的影响

光照能明显改变正常人和动物瞳孔的大小,而精神疾病及药物滥用则影响人和动物瞳孔对光的反应性。因此,瞳孔对光反应异常可以用作检测精神疾病和药物滥用的指标。有关药物滥用是如何影响瞳孔对光的反应性的研究还很少。为定量地测量成瘾性药物对瞳孔光反应变化的影响,该文采用猕猴为实验对象,通过在黑暗环境中测量猕猴在吗啡给予前和吗啡给予后的不同时间段,其瞳孔直径大小以及其对光反应能力的变化情况,来系统研究吗啡是如何影响这种非自主性反射系统的。研究发现,吗啡给予降低了猕猴在黑暗环境中的扩瞳反应,并且降低了瞳孔对光反应的收缩率。该文为将瞳孔对光反应特征用作鉴定吸毒者的检测手段提供了实验依据。

中国鲤科鱼类新记录--小口猪嘴ba

鲤科鱼类区系中猪嘴ba属Systomus和小口猪嘴Systomus orphoides(Valenciennes 1842)的首次记录。标本保存于中国科学院昆明动物研究所鱼类标本室。

Nest site selection by Black-necked Crane Grus nigricollis in the Ruoergai Wetland, China

From 5 May 2003 to early June 2005, nest site selection of Black-necked Cranes Grits nigricollis was studied at the Ruoergai Wetland Nature Reserve (RWNR), an important breeding area for the species in China. Results showed that the crane nests only in we

八种大鼠染色体银染核仁组织者的比较研究

银染色观察发现, 我国8种大鼠银染核仁组织者Ag-NORs的数目和分布均存在一定的差异, 在不同细胞之间和同源染色体之间均呈现较为明显的多态性以及Ag-NORs的联合现象和异形现象。模糊聚类分析, 获得8种大鼠的聚类分析支图, 结合地理分布等指标对其分类地位和相似关系作了初步探讨。图1表5参30

双滴虫与细胞核起源问题的探索

分析了可能用作研究原始性细胞核的模型的涡鞭毛虫与双滴虫核, 发现实际上只有后者是适用的。认为在真核细胞的原细菌祖先体内就已经有了核骨架; 多个类核体的DNA结合在其上而构成了核区。真核细胞的原细菌祖先很早就有了4种核小体组蛋白和核小体。着重分析了染色体的起源过程并进一步发展了过去提出的核被膜起源于原始性内质网的学说, 并分析记述了原始性细胞核的进化过程。

抑制启动子的三链DNA的结构模建及稳定性研究

在IRIS Indigo2(SGI公司)工作站上,利用InsightⅡ/MSI软件包,以TAT三链DNA为模板,采用同源模建的方法,分别建立起两个含21nt的脱氧寡核苷酸CP1(G3TG2TGT2G5TG2TGT)和CP3(TGTG2TG5T2GTG2TG3)的三维结构。采用分子力学方法进行能量优化,将得到的能量最低结构作为分子的优势构象。研究结果显示,CP1的能量低于CP3的能量,即前者的结构较后者稳定。

Stability and molecular modeling of triplex DNA inhibiting DNA binding protein binding to the core promoter of hepatitis B virus.

Two three-dimensional structure models of the 21nt oligodeoxyribonucleotides, CPI (G3TG-2TGT2G5TG2TGT) and CP3 (TGTG2TGST2GTG2TG3), were constructed by InsightII (MSI) software in IRIS Indigo2 (SGI) workstation using the crystal structure of TAT tripler formation as the template. The initial structures subsequently were minimized by molecular mechanics. The final structures were believed as the dominant conformation. The results showed that the energy of CP1 is lower than that of CP3, and the former is more stable than the latter. Moreover, the results further proved that the 21nt oligodeoxyribo-nucleotide CP1 stably combines with the core promoter (Cp) fragment of hepatitis B virus (HBV) to form a tripler DNA, and CP1 specifically inhibits a specific cellular factor (DNA binding protein) binding to Cp fragment. These results indicated that specific repression of gene transcription of HBV DNA might be possible by tripler-formation DNA.