Up-Regulation of MicroRNA-145 Associates with Lymph Node Metastasis in Colorectal Cancer

Metastasis is the main cause of mortality in patients with solid tumours. Identifying the exact molecules associated with CRC metastasis may be crucial to understand the process, which might also be translated to the diagnosis and treatment of CRC. In this study, we investigate the association of microRNA expression patterns with the lymph node metastasis of colorectal cancer. Among these candidate miRNAs, the expression of miRNA-145 was significantly related to lymph node metastasis of CRC. Both in vitro and in vivo study demonstrated that up-regulation of miR-145 could improve the ability of migration and invasion of colorectal cancer cell, while no effect on proliferation was observed. The mechanism of this promotion is associated with the stabilization of Hsp-27, a protein which plays an important role in the promotion of metastasis. These results may be crucial to understanding CRC metastasis and may be translated to the diagnosis and treatment of CRC.     

Catastrophic Health Expenditure and Rural Household Impoverishment in China: What Role Does the New Cooperative Health Insurance Scheme Play?

Objective

To determine whether the New Cooperative Medical Insurance Scheme (NCMS) is associated with decreased levels of catastrophic health expenditure and reduced impoverishment due to medical expenses in rural households of China.

Methods

An analysis of a national representative sample of 38,945 rural households (129,635 people) from the 2008 National Health Service Survey was performed. Logistic regression models used binary indicator of catastrophic health expenditure as dependent variable, with household consumption, demographic characteristics, health insurance schemes, and chronic illness as independent variables.

Results

Higher percentage of households experiencing catastrophic health expenditure and medical impoverishment correlates to increased health care need. While the higher socio-economic status households had similar levels of catastrophic health expenditure as compared with the lowest. Households covered by the NCMS had similar levels of catastrophic health expenditure and medical impoverishment as those without health insurance.

Conclusion

Despite over 95% of coverage, the NCMS has failed to prevent catastrophic health expenditure and medical impoverishment. An upgrade of benefit packages is needed, and effective cost control mechanisms on the provider side needs to be considered.     

Mycobacterium tuberculosis Rv3402c Enhances Mycobacterial Survival within Macrophages and Modulates the Host Pro-Inflammatory Cytokines Production via NF-Kappa B/ERK/p38 Signaling

Intracellular survival plays a central role in the pathogenesis of Mycobacterium tuberculosis, a process which depends on an array of virulence factors to colonize and replicate within the host. The M. tuberculosis iron regulated open reading frame (ORF) rv3402c, encoding a conserved hypothetical protein, was shown to be up-regulated upon infection in both human and mice macrophages. To explore the function of this ORF, we heterologously expressed the rv3402c gene in the non-pathogenic fast-growing Mycobacterium smegmatis strain, and demonstrated that Rv3402c, a cell envelope-associated protein, was able to enhance the intracellular survival of recombinant M. smegmatis. Enhanced growth was not found to be the result of an increased resistance to intracellular stresses, as growth of the Rv3402c expressing strain was unaffected by iron depletion, H₂O₂ exposure, or acidic conditions. Colonization of macrophages by M. smegmatis expressing Rv3402c was associated with substantial cell death and significantly greater amount of TNF-α and IL-1β compared with controls. Rv3402c-induced TNF-α and IL-1β production was found to be mediated by NF-κB, ERK and p38 pathway in macrophages. In summary, our study suggests that Rv3402c delivered in a live M. smegmatis vehicle can modify the cytokines profile of macrophage, promote host cell death and enhance the persistence of mycobacterium within host cells.     

Antimicrobial Resistance of Shigella flexneri Serotype 1b Isolates in China

Shigella flexneri serotype 1b is among the most prominent serotypes in developing countries, followed by serotype 2a. However, only limited data is available on the global phenotypic and genotypic characteristics of S. flexneri 1b. In the present study, 40 S. flexneri 1b isolates from different regions of China were confirmed by serotyping and biochemical characterization. Antimicrobial susceptibility testing showed that 85% of these isolates were multidrug-resistant strains and antibiotic susceptibility profiles varied between geographical locations. Strains from Yunnan were far more resistant than those from Xinjiang, while only one strain from Shanghai was resistant to ceftazidime and aztreonam. Fifteen cephalosporin resistant isolates were identified in this study. ESBL genes (bla _SHV, bla _TEM, bla _OXA, and bla _CTX-M) and ampC genes (bla _MOX, bla _FOX, bla _MIR(ACT-1), bla _DHA, bla _CIT and bla _ACC) were subsequently detected among the 15 isolates. The results showed that these strains were positive only for bla _TEM, bla _OXA, bla _CTX-M, intI1, and intI2. Furthermore, pulsed-field gel electrophoresis (PFGE) analysis showed that the 40 isolates formed different profiles, and the PFGE patterns of Xinjiang isolates were distinct from Yunnan and Shanghai isolates by one obvious, large, missing band. In summary, similarities in resistance patterns were observed in strains with the same PFGE pattern. Overall, the results supported the need for more prudent selection and use of antibiotics in China. We suggest that antibiotic susceptibility testing should be performed at the start of an outbreak, and antibiotic use should be restricted to severe Shigella cases, based on resistance pattern variations observed in different regions. The data obtained in the current study might help to develop a strategy for the treatment of infections caused by S. flexneri 1b in China.     

A “one-marker-for-two-genes” approach for efficient molecular discrimination of Pm12 and Pm21 conferring resistance to powdery mildew in wheat

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is one of the most important wheat diseases worldwide. Pyramiding different resistance genes into single cultivar has been proposed as one remedy to provide durable resistance. Powdery mildew resistance genes Pm12 (T6BS-6SS.6SL), transferred from Aegilops speltoides to wheat cv. Wembley, and Pm21 (T6VS.6AL), introduced from Dasypyrum villosum to wheat cv. Yangmai5, conferred broad-spectrum resistance to B. graminis f. sp. tritici. Both Pm12 and Pm21 genes are located on the short arms of homologous group six involved translocated chromosomes 6SS.6BL and 6VS.6AL, respectively. Simple sequence repeat motifs of wheat simple sequence repeat (SSR) and expressed sequence tag (EST) sequences on the short arm of homologous group six chromosomes were analyzed to develop molecular markers for discriminating chromosome arms 6AS, 6BS, 6DS, 6VS, and 6SS. One EST–SSR marker, Xcau127, was polymorphic, and therefore can be used to distinguish the two resistance genes and the respective susceptible alleles. This marker allowed us to develop an efficient “one-marker-for-two-genes” procedure for identifying powdery mildew resistance genes Pm12 and Pm21 for marker-assisted selection and gene pyramiding in wheat breeding programs. Wei Song and Chaojie Xie contributed equally to this work     

部分小麦近缘物种材料的白粉病抗性鉴定

鉴定了170份小麦近缘物种材料苗期对北京地区流行的小麦白粉菌小种的抗性表现,包括引自美国和欧洲的斯卑尔脱小麦81份,密穗小麦27份,中国的西藏半野生小麦4份,和引自 CIMMYT 的人工合成六倍体小麦58份。结果表明,3份斯卑尔脱小麦表现抗病,它们是瑞士品种 Hubel 和 Lueg 以及德国的原始品种69Z6.245(编号 PI348085)。人工合成六倍体小麦中有19份材料表现高抗至免疫。密穗小麦材料中有2份(即美国材料 DN-2263和 Coda)表现抗病。4份西藏半野生小麦苗期都不抗小麦白粉病。     

黑侧沟姬蜂的生物学及种群消长规律研究

黑侧沟姬蜂(Casinaria nigripes Gravenhorst)是马尾松毛虫(Dendrolimus punctotus Walker)的主要寄生天敌,它主要寄生1—4龄松毛虫幼虫,其最高寄生率达66.64％。 黑侧沟姬蜂的全世代发育起点温度为9.0±0.6℃,有效积温446.9日度,在湖南浏阳县每年发生6—7代,以幼虫在松毛虫幼虫体内越冬。幼虫老熟时钻出寄主,爬至松针或松枝上结茧化蛹。在不同的生境中,该蜂对松毛虫的寄生率有明显差异,以在松阔混交林中寄生率最高,对各代松毛虫的年平均寄生率可达36.58％,而在植被稀少的疏残松林中寄生率最低,仅11.66％。其寄生率还随寄主世代不同而异,一般以对第3代松毛虫的寄生率最高,第1代次之,第2代最低。该蜂种群数量逐年波动与全年霜冻日数成负相关,与当年7、8月份降雨量和10月份平均气温成正相关。     

Transcriptome analysis uncovers the autophagy‐mediated regulatory patterns of the immune microenvironment in dilated cardiomyopathy

The relationship between autophagy and immunity has been well studied. However, little is known about the role of autophagy in the immune microenvironment during the progression of dilated cardiomyopathy (DCM). Therefore, this study aims to uncover the effect of autophagy on the immune microenvironment in the context of DCM. By investigating the autophagy gene expression differences between healthy donors and DCM samples, 23 dysregulated autophagy genes were identified. Using a series of bioinformatics methods, 13 DCM‐related autophagy genes were screened and used to construct a risk prediction model, which can well distinguish DCM and healthy samples. Then, the connections between autophagy and immune responses including infiltrated immunocytes, immune reaction gene‐sets and human leukocyte antigen (HLA) genes were systematically evaluated. In addition, two autophagy‐mediated expression patterns in DCM were determined via the unsupervised consensus clustering analysis, and the immune characteristics of different patterns were revealed. In conclusion, our study revealed the strong effect of autophagy on the DCM immune microenvironment and provided new insights to understand the pathogenesis and treatment of DCM.