人防御素的研究进展

人防御素是近年发现的人体内重要的内源性抗生素,已引起国内外生物和医学研究者的日益重视。这里综述了人防御素的组织分布、分子生物学特点、作用机理、医学及药用价值等方面的研究进展,对采用基因重组方法生产人防御素的方法进行了评述,并展望了防御素的应用前景和发展趋势。     

白裤瑶体质人类学研究

本文对953名(男605人,女348人)生活在贵州和广西接境地带的白裤瑶民族进行了活体调查(观察28个项目,测量63个项目)。调查对象年龄为22—55岁,三代均系白裤瑶。分析结果表明：白裤瑶属蒙古人种南亚类型,具有典型现代黄种人的容貌特征。多为圆头型,以超狭面型多见,属中鼻型,矮型身材。白裤瑶与南方16个少数民族群体10项头面部体部测量数据聚类分析,结果显示白裤瑶人群的体质特征与贵州毛南族、湖南侗族、云南苗族最为接近,与广西苗族、彝族、侗族、瑶族次之,与贵州苗族、水族以及湖南土家族、瑶族等民族较远。     

青阳参种子的萌发

青阳参（Cynanchum otophyllum）种子在11月成熟时有休眠习性。收获后将其种子种植在自然温室内,到第二年的春天种子才会萌发,且大多数种子在3月28至4月4日间萌发,这期间的日平均最高和最低温度分别为19．0℃和9．9℃。层积能有效地打破青阳参种子的休眠,休眠种子通过大约1周的层积便能萌发。种子在有光的条件下层积1周后转移到25／15℃的黑暗条件下萌发率可达到75．4％。青阳参种子不论在有光的条件下还是在黑暗环境中层积2～3周后转入30／20和25／15℃进行变温处理,其萌发率最低能达到66．4％,而转入20／10℃变温处理其萌发率最多只能达到20．1％,但若层积6周,即便在20／10℃变温处理的情况下其萌发率也可以达到65．3％以上。     

紫斑蝴蝶草的组织培养和快速繁殖

1 植物名称 紫斑蝴蝶草（Torenia fordii Hook. f.）。 2 材料类别 种子萌发形成的叶片。 3 培养条件 不定芽诱导培养基：（1）MS＋CPPU（氯吡苯脲,forchlorfenuron）0.01mg·L^-1（单位下同）;（2）MS＋CPPU0.05;（3）MS＋CPPU0.10;（4）MS＋TDZ（噻苯隆,thidiazuron）0.01;（5）MS＋TDZ0.05;（6）MS＋TDZ0.10。     

Gene mapping related to yellow green leaf in a mutant line in rice (Oryza sativa L.)

A mutant, which derived from the restorer line Jinhui10 treated with EMS, showed completely yellow green leaves, and it had low chlorophyll content and poor agronomic characteristics during the growing stage. The F1 plants from the cross between normal × the mutant showed normal green leaves, and the segregation ratio of normal to yellow green leaves was 3 : 1 in F₂ population. It indicated that the trait was controlled by a single recessive nuclear gene, temporarily designated asygl3. The geneygl3 was mapped between RM468 and RM3684 with genetic distances 8.4 cM and 1.8 cM on chromosome 3. This result would be used as genetic information for fine mapping and map-based cloning ofygl3 gene.     

Overexpression of the MUC2 gene through promoter hypomethylation in mucinous cell carcinomas and signet ring cell carcinomas of gastric cancer

Gastric carcinoma (GC) remains an important cause of mortality and morbidity in East Asia and the histological classification is still controversial, despite considerable understanding of the molecular nature of this disease and its precursor lesions. Mucins play important roles in carcinogenesis or tumor invasion and their aberrant expression are also associated with pathophysiological conditions and clinical outcomes. To investigate if differences with MUC2 expression in GC are associated through changes in promoter methylation and to evaluate the relationship with the histological features of GCs, the expression and methylation status of MUC2 gene was examined in samples from 40 gastric mucosa of GC by immunohistochemistry (IHC) and by methylation-specific PCR (MSP). MUC2 was minimally and focally expressed in welldifferentiated (WD) and moderately-differentiated (MD) GC, while mucinous cell carcinomas (MCC) and signet ring cell carcinomas (SRC) displayed a uniform and strong staining intensity with a diffused cytoplasmic pattern. In addition, the MUC2 hypomethylation were found in 33% of the WD, 0% of the MD, 77% of the MCC, 75% of the MCC/SRC, and 80% of the SRC. Moreover, IHC and MSP analyses showed that MUC2 hypomethylation correlated with its overexpression. Collectively, these results suggest that MUC2 overexpression event in MCC and SRC types of GCs. However, further studies with large numbers of patients will be needed to confirm these findings.     

Identification of natural compounds targeting Annexin A2 with an anti-cancer effect

Annexin A2, a multifunctional tumor associated protein, promotes nuclear factor-kappa B (NF-κB) activation by interacting with NF-κB p50 subunit and facilitating its nuclear translocation. Here we demonstrated that two ginsenosides Rg5 (G-Rg5) and Rk1 (G-Rk1), with similar structure, directly bound to Annexin A2 by molecular docking and cellular thermal shift assay. Both Rg5 and Rk1 inhibited the interaction between Annexin A2 and NF-κB p50 subunit, their translocation to nuclear and NF-κB activation. Inhibition of NF-κB by these two ginsenosides decreased the expression of inhibitor of apoptosis proteins (IAPs), leading to caspase activation and apoptosis. Over expression of K302A Annexin A2, a mutant version of Annexin A2, which fails to interact with G-Rg5 and G-Rk1, effectively reduced the NF-κB inhibitory effect and apoptosis induced by G-Rg5 and G-Rk1. In addition, the knockdown of Annexin A2 largely enhanced NF-κB activation and apoptosis induced by the two molecules, indicating that the effects of G-Rg5 and G-Rk1 on NF-κB were mainly mediated by Annexin A2. Taken together, this study for the first time demonstrated that G-Rg5 and G-Rk1 inhibit tumor cell growth by targeting Annexin A2 and NF-κB pathway, and G-Rg5 and G-Rk1 might be promising natural compounds for targeted cancer therapy.     

Chronic Hepatitis C Virus Infection Is Associated with the Development of Rheumatoid Arthritis: A Nationwide Population-Based Study in Taiwan

ObjectiveThe association between chronic hepatitis virus infection and rheumatoid arthritis (RA) remains debatable. This nationwide population-based cohort study assessed the risk of RA among patients with a chronic infection of hepatitis B and/or C virus.ResultsAfter adjusting for covariates, chronic HCV infection alone was significantly associated with an increased risk for RA (hazard ratio (HR)  = 2.03, 95% confidence interval (CI)  = 1.27–3.22). The increased risk for RA among participants with chronic HCV infection remained significant after restricting the analysis to those who were prescribed disease-modifying anti-rheumatic drugs. The corresponding HR for the overall sample was 1.89 (95% CI  = 1.15–3.11). However, HBV carriers did not appear to be at a significantly higher risk for RA.ConclusionOur data imply that chronic HCV infection is associated with RA development.     

Renal Involvement in Non-Hodgkin Lymphoma: Proven by Renal Biopsy

Aims

To determine the spectrum of renal lesions in patients with kidney involvement in non-Hodgkin''s lymphoma (NHL) by renal biopsy.

Methods

The clinical features and histological findings at the time of the renal biopsy were assessed for each patient.

Results

We identified 20 patients with NHL and renal involvement, and the diagnosis of NHL was established following the kidney biopsy in 18 (90%) patients. The types of NHL include the following: chronic lymphocytic leukemia/small lymphocytic lymphoma (n = 8), diffuse large B-cell lymphoma (n = 4), T/NK cell lymphoma (n = 3), lymphoplasmacytic lymphoma (n = 2), cutaneous T-cell lymphoma (n = 1), mucosa-associated lymphoid tissue lymphoma (n = 1) and mantle cell lymphoma (n = 1). All presented with proteinuria, and 15 patients had impaired renal function. The pathological findings included (1) membranoproliferative glomerulonephritis-like pattern in seven patients; (2) crescent glomerulonephritis in four; (3) minimal-change disease in three, and glomeruli without specific pathological abnormalities in three; (4) intraglomerular large B-cell lymphoma in one; (5) intracapillary monoclonal IgM deposits in one; (6) primary diffuse large B-cell lymphoma of the kidneys in one; and (7) lymphoma infiltration of the kidney in eight patients.

Conclusion

A wide spectrum of renal lesions can be observed in patients with NHL, and NHL may be first proven by renal biopsies for evaluation of kidney injury or proteinuria. Renal biopsy is necessary to establish the underlying cause of renal involvement in NHL.     

Dimerization Interface of 3-Hydroxyacyl-CoA Dehydrogenase Tunes the Formation of Its Catalytic Intermediate

3-hydroxyacyl-CoA dehydrogenase (HAD, EC 1.1.1.35) is a homodimeric enzyme localized in the mitochondrial matrix, which catalyzes the third step in fatty acid β-oxidation. The crystal structures of human HAD and subsequent complexes with cofactor/substrate enabled better understanding of HAD catalytic mechanism. However, numerous human diseases were found related to mutations at HAD dimerization interface that is away from the catalytic pocket. The role of HAD dimerization in its catalytic activity needs to be elucidated. Here, we solved the crystal structure of Caenorhabditis elegans HAD (cHAD) that is highly conserved to human HAD. Even though the cHAD mutants (R204A, Y209A and R204A/Y209A) with attenuated interactions on the dimerization interface still maintain a dimerization form, their enzymatic activities significantly decrease compared to that of the wild type. Such reduced activities are in consistency with the reduced ratios of the catalytic intermediate formation. Further molecular dynamics simulations results reveal that the alteration of the dimerization interface will increase the fluctuation of a distal region (a.a. 60–80) that plays an important role in the substrate binding. The increased fluctuation decreases the stability of the catalytic intermediate formation, and therefore the enzymatic activity is attenuated. Our study reveals the molecular mechanism about the essential role of the HAD dimerization interface in its catalytic activity via allosteric effects.