Synonymous Codon Usage Bias in Plant Mitochondrial Genes Is Associated with Intron Number and Mirrors Species Evolution

Synonymous codon usage bias (SCUB) is a common event that a non-uniform usage of codons often occurs in nearly all organisms. We previously found that SCUB is correlated with both intron number and exon position in the plant nuclear genome but not in the plastid genome; SCUB in both nuclear and plastid genome can mirror the evolutionary specialization. However, how about the rules in the mitochondrial genome has not been addressed. Here, we present an analysis of SCUB in the mitochondrial genome, based on 24 plant species ranging from algae to land plants. The frequencies of NNA and NNT (A- and T-ending codons) are higher than those of NNG and NNC, with the strongest preference in bryophytes and the weakest in land plants, suggesting an association between SCUB and plant evolution. The preference for NNA and NNT is more evident in genes harboring a greater number of introns in land plants, but the bias to NNA and NNT exhibits even among exons. The pattern of SCUB in the mitochondrial genome differs in some respects to that present in both the nuclear and plastid genomes.     

细菌(Pseudomonas maltophilia)之绒毛膜促性腺激素(hCG)结合物质之研究

 细菌(Pseudomonas moltophilia)与hCG及LH有特异的亲和力,实验发现,细菌之生长曲线与hCG结合活性成平行关系,96小时达高峰,细菌之培养液中含有可溶性结合蛋白,该蛋白经硫酸铵沉淀(80％饱和度)、Sephadex G-100柱层析、DEAE-纤维素柱0.5mol/L NaCl梯度洗脱,再过Sepharose CL-AB柱,收集之活性部分经SDS电泳测得其分子量为70,000,凝胶层析测Stokes radius为41A,Schiff氏染色未见着色带。     

RORα高表达对二烯丙基二硫抑制人胃癌细胞增殖与迁移侵袭的影响

目的观察高表达RORα对二烯丙基二硫(DADS)抑制人胃癌MGC803细胞增殖、迁移与侵袭的影响。方法集落形成实验与流式细胞术检测细胞增殖与细胞周期;细胞划痕和Transwell实验分别检测细胞迁移与侵袭。RT-PCR与Western blot分别检测RORα、MMP-9和TIMP3 mRNA与蛋白表达水平。结果RT-PCR与Western blot检测显示,RORα高表达与DADS处理较对照组与空载体组RORαmRNA与蛋白表达明显上调,DADS+RORα高表达组上调更为显著(P<0.05)。与对照组和空载体组比较,RORα高表达与DADS处理组MMP-9表达下调,TIMP3表达上调,DADS+RORα高表达组改变最为显著。集落形成实验显示,RORα高表达与DADS处理组较对照组与空载体组的集落形成率明显降低。流式细胞术显示,与对照组和空载体组比较,RORα高表达与DADS处理组G2/M期细胞比率明显升高。细胞划痕和Transwell实验显示,RORα高表达与DADS处理组细胞迁移与侵袭能力明显降低。结论RORα高表达可通过上调TIMP3与下调MMP-9促进DADS阻滞MGC803细胞G2/M期和抑制增殖与迁移侵袭。     

Absence of estrogen receptor beta leads to abnormal adipogenesis during early tendon healing by an up‐regulation of PPARγ signalling

Achilles tendon injury is one of the challenges of sports medicine, the aetiology of which remains unknown. For a long time, estrogen receptor β (ERβ) has been known as a regulating factor of the metabolism in many connective tissues, such as bone, muscle and cartilage, but little is known about its role in tendon. Recent studies have implicated ERβ as involved in the process of tendon healing. Tendon‐derived stem cells (TDSCs) are getting more and more attention in tendon physiological and pathological process. In this study, we investigated how ERβ played a role in Achilles tendon healing. Achilles tendon injury model was established to analyse how ERβ affected on healing process in vivo. Cell proliferation assay, Western blots, qRT‐PCR and immunocytochemistry were performed to investigate the effect of ERβ on TDSCs. Here, we showed that ERβ deletion in mice resulted in inferior gross appearance, histological scores and, most importantly, increased accumulation of adipocytes during the early tendon healing which involved activation of peroxisome proliferator‐activated receptor γ (PPARγ) signalling. Furthermore, in vitro results of ours confirmed that the abnormity might be the result of abnormal TDSC adipogenic differentiation which could be partially reversed by the treatment of ERβ agonist LY3201. These data revealed a role of ERβ in Achilles tendon healing for the first time, thereby providing a new target for clinical treatment of Achilles tendon injury.     

狭叶柴胡的抗过敏活性及其有效成分

本文以compound 48／80在体外诱导大鼠腹腔肥大细胞释放组胺,评价狭叶柴胡及其成分的抗过敏活性。狭叶柴胡醇提物及正丁醇部分(100μg／mL)、乙酸乙酯及水部分(10,100μg／mL)显著减少组胺释放,以乙酸乙酯部分的作用最强,狭叶柴胡挥发油(100μg／mL)对组胺释放呈现一定的促进作用。从乙酸乙酯部分分离得到异鼠李素和槲皮素两种主要化合物,均显著抑制组胺释放,表明黄酮为狭叶柴胡抗过敏作用的有效成分。     

Physiological characteristics of the primitive CO2 concentrating mechanism in PEPC transgenic rice

C4 plants such as maize have CO2 concentrating mechanism and higher photosynthetic efficiency than C3 plants, especially under high light intensity, high temperature and drought conditions. In recent years, due to the rapid development of transgenic technique, different transgenic rice plants with high-level expression of C4 genes have been created by the successful introduction of genes encoding the key C4 photosynthetic path enzymes PEPC, PPDK and NADP-ME through agrobacteria-mediated…     

A peptide mimetic of Gal-alpha 1,3-Gal is able to block human natural antibodies

The carbohydrate of Gal-alpha1,3-Gal is thought to be the major antigenic epitope present on pig vascular endothelium. The peptides that mimic the binding of antigenic epitope (Gal-alpha1,3-Gal) to lectin BS-I-B4 were identified from screening a filamentous phage-displayed random library. A phage bearing the peptide NCVSPYWCEPLAPSARA has been identified to bind the lectin strongly. Melibiose was able to inhibit the binding of the human natural anti-alpha Gal antibody to the peptide competitively. Our experiments show that the peptide mimetic of Gal-alpha1,3-Gal is able to inhibit the agglutination of pig RBCs by human natural antibody or lectin BS-I-B4. The peptide inhibitor of human natural antibodies may prove useful in pig-to-human xenotransplantation.     

Duvira Antarctic polysaccharide inhibited H1N1 influenza virus-induced apoptosis through ROS mediated ERK and STAT-3 signaling pathway

Background

The H1N1 influenza virus causes acute respiratory tract infection, and its clinical symptoms are very similar to those of ordinary influenza. The disease develops rapidly. If the flu is not treated, complications such as pneumonia, respiratory failure, and multiple organ damage can occur, resulting in a high fatality rate. Influenza virus mutates rapidly. At present, there is no specific drug for H1N1, so it is an urgent need for clinical care to find new drugs to treat H1N1.

Materials and methods

The polysaccharide derived from Durvillaea Antarctica green algae has a certain antiviral effect. In this study, the results of CCK-8, apoptosis cycle detection, JC-1 and Western blotting proved that Duvira Antarctic polysaccharide (DAPP) has the ability to inhibit H1N1 infection.

Results

CCK-8 test showed that the DAPP with concentration at 32 μg/mL had no toxicity to MDCK cells. In addition, DAPP reduced cell apoptosis by inhibiting the ERK signaling pathway. Meanwhile, DAPP could increase the expression of STAT3 and significantly inhibited proinflammatory cytokines.

Conclusions

In summary, these results suggested that DAPP may be potential with the ability to resist the H1N1 influenza virus.

     

Ostericum atropurpureum sp. nov. (Apiaceae) from Zhejiang,China

Ostericum atropurpureum G. Y. Li, G. H. Xia & W. Y. Xie (Apiaceae, Apioideae) from Zhejiang, China, is described and illustrated. It is closely related to O. huadongense Z. H. Pan & X. H. Li and O. sieboldii (Miquel) Nakai, but differs in having leaves with 1.5–9.0 cm long petiole, linear bracteoles 6–12 mm long, 5–9 rays, 7–14‐flowered umbellules, dark purple petals, broadly winged dorsal and lateral fruit ribs, 1.0–1.5 mm broad, 3–6 vittae in each furrow and 4–8 on the commissure.     

Pulmonary Tuberculosis Incidence and Risk Factors in Rural Areas of China: A Cohort Study

The incidence of tuberculosis (TB) and its risk factors in China remains unclear. This study examined TB incidence and relative risk factors in rural areas of China. Participants (n = 177,529) were recruited in Xiangtan County (in the central area of China) and in Danyang County (in the eastern area of China) in 2009 and a followed-up study was conducted for one year. The incidence density of pulmonary TB and smear-positive TB were 91.6 (95% CI: 78.7, 106.0) per 100,000 person-year and 36.7 (95% CI: 33.1, 52.4) per 100,000 person-year respectively in Xiangtan, and 47.3 (95% CI: 38.2, 57.5) per 100,000 person-year and 22.7 (95% CI: 16.5, 30.8) per 100,000 person-year in Danyang. The medical history of TB was associated with TB, with the relative risk (RR) of 7.00 (95% CI: 2.76, 17.18) in Xiangtan and that of 31.08 (95% CI: 13.22, 73.10) in Danyang. The association between TB and per capita living space over median was found in Xiangtan, with the RR of 1.86 (95% CI: 1.15, 3.01). No association was found between TB and the insurance status, the contact history with TB, the history of diabetes, smoking, or per capita annual income. The host genetic susceptibility, and social factors such as education and income could be considered in future studies.