特色香料作物油樟叶内生Bacillus velezensis YZ12的鉴定及拮抗病原菌活性

植物内生菌关系到植物的健康生长,且与植物产生的相关功效产物紧密关联。以我国四川宜宾油樟叶片分离筛选得到的内生细菌作为研究对象,利用传统微生物培养方法,基于形态学观察,16S rRNA和gyrA基因系统发育分析的多相分类学方法,将其鉴定为贝莱斯芽胞杆菌(Bacillus velezensis);并通过对从油樟叶片中分离的油樟真菌YZP-01以及常见植物病原真菌绳状篮状菌(Talaromyces funiculosus)、拟轮枝镰孢菌(Fusarium verticillioides)、草酸青霉(Penicillium oxalicum)四种致病菌株进行了拮抗试验,发现了该菌株具有广谱且良好的拮抗病原菌活性。使用特定引物扩增功能基因(bioA,bmyB,ituC,fenD,srfAA,srfAB,yngG和yndJ),并成功从菌株YZ12中扩增出这些基因。     

DLGAP1-AS2 promotes human colorectal cancer progression through trans-activation of Myc

Mammalian Genome - Substantial evidence suggests that non-coding RNA plays a vital role in human cancer, especially long non-coding RNA (lncRNA) with a length greater than 200nt. Herein, we found a...     

Development of Skewed Functionality of HIV-1-Specific Cytotoxic CD8+ T Cells from Primary to Early Chronic Phase of HIV Infection

In recent years, the prevalence of HIV-1 infection has been rapidly increasing among men who have sex with men (MSM). However, it remains unknown how the host immune system responds to the infection in this population. We assessed the quantity of HIV-specific CD8⁺ T-cell responses by using Elispot assay and their functionalities by measuring 5 CD8⁺ T-cell evaluations (IL-2, MIP-1β, CD107a, TNF-α, IFN-γ) with flow cytometry assays among 18 primarily and 37 early chronically HIV-infected MSM. Our results demonstrated that subjects at early chronic phase developed HIV-specific CD8⁺ T-cell responses with higher magnitudes and more diversified functionalities in comparison with those at primary infection. However, populations with IL-2⁺ CD107a⁺ or in combination with other functionality failed to develop in parallel. The multifunctional but not monofunctional HIV-specific CD8⁺ T cells were associated with higher CD4⁺ T -cell counts and lower viral loads. These data revealed that prolonged infection from primary to early chronic infection could selectively increase the functionalities of HIV-specific CD8⁺ T cells in HIV-infected MSM population, the failure to develop IL-2 and cytotoxic functionalities in parallel may explain why the increased HIV-specific CD8⁺ T cells were unable to enhance the containment of HIV-1 replication at the early chronic stage.     

Enhancement of the direct antimicrobial activity of Lysep3 against <Emphasis Type="Italic">Escherichia coli</Emphasis> by inserting cationic peptides into its C terminus

Phage lysins are considered promising antimicrobials against resistant bacterial infections. Some lysins have been reported for the prevention and treatment of Gram-positive bacterial infection. Gram-negative bacterial phage lysins, however, can only destroy the bacterial cell wall from inside because of the obstruction of the bacterial outer membrane that prevents direct hydrolysis of the bacterial wall peptidoglycan from the outside, severely restricting the development of lysins against Gram-negative bacteria. In this study, genetic engineering techniques were used to fuse a 5 cationic amino acid polypeptide (KRKRK), a 10 cationic amino acid polypeptide (KRKRKRKRKR), a 15 cationic amino acid polypeptide (KRKRKRKRKRKRKRK), and a polypeptide including both cationic and hydrophobic amino acids (KRKRKFFVAIIP) to the C-terminus of the Escherichia coli phage lysin Lysep3 to obtain four fusion lysins (5aa, 10aa, 15aa, Mix). The bactericidal effects of those four lysins on E. coli were then compared in vitro. Our results showed that the fusion of hydrophobic and positively charged amino acids, Mix, can kill E. coli effectively; the fusion of positively charged amino acids alone at the C-terminus (5aa, 10aa, 15aa) also showed bactericidal activity against E. coli from the outside, with the bactericidal activity gradually increasing with the positive charge at the C-terminus of the lysin. Collectively, improving the positive charge at the C-terminus of E. coli bacteriophage lysin Lysep3 increases its bactericidal ability from outside E. coli, providing a new practical method for the development of anti-Gram-negative bacterial lysins.     

Coronavirus transmissible gastroenteritis virus antagonizes the antiviral effect of the microRNA miR-27b via the IRE1 pathway

Science China Life Sciences - Although the functional parameters of microRNAs (miRNAs) have been explored to some extent, the roles of these molecules in coronavirus infection and the regulatory...     

有机食品、绿色食品和无公害食品

介绍了有机食品、绿色食品和无公害食品的内涵及标准体系,并进行了分析比较。     

Laparoscopic Nephrectomy versus Open Nephrectomy for Patients with Autosomal Dominant Polycystic Kidney Disease: A Systematic Review and Meta-Analysis

Objective

To compare efficacy and safety of laparoscopicnephrectomy (LN) versusopen nephrectomy (ON) in the management of autosomal dominant polycystic kidney disease (ADPKD), we conducted a systematic review and meta-analysis.

Methods

A systematic search of the electronic databases PubMed, Scopus, and the Cochrane Library was performed up to October 2014.This systematic review was performed based on observational comparative studies that assessed the two techniques. The weighted mean difference (WMD) and risk ratio (RR), with their corresponding 95% confidence interval (CI), were calculated to compare continuous and dichotomous variables, respectively.

Results

Seven studies were identified, including 195 cases (118 LN / 77 ON). Although LN was associated with longer operative time (WMD 30.236, 95%CI 14.541 −45.932, P<0.001) and the specimen might not have been resected as heavy as the ON group (WMD -986.516, 95%CI -1883.24–-89.795, P = 0.031), patients in this group might benefit from a shorter length of hospital stay (WMD -3.576, 95%CI 4.976–-2.176, P <0.001), less estimated blood loss (WMD -180.245, 95%CI -317.939–-42.556, P = 0.010), and lower need of transfusion (RR 0.345, 95%CI 0.183–0.650, P = 0.001). The LN group also had less overall complications (RR 0.545, 95%CI 0.329–0.903, P = 0.018). The need of narcotic analgesics between the two groups might have no significant difference (WMD -54.66, 95%CI -129.76–20.44, P = 0.154).

Conclusion

LN for giant symptomatic ADPKD was feasible, safe and efficacious. Morbidity was significantly reduced compared with the open approach. For an experienced laparoscopist, LN might be a better alternative.     

Antimicrobial Peptide JH-3 Effectively Kills Salmonella enterica Serovar Typhimurium Strain CVCC541 and Reduces Its Pathogenicity in Mice

Salmonella is an important zoonotic pathogen and is a major cause of gastrointestinal diseases worldwide. The current serious problem of antibiotic abuse has prompted the search for new substitutes for antibiotics. JH-3 is a small antimicrobial peptide with broad-spectrum bactericidal activity. In this study, we showed that JH-3 has good bactericidal activity towards the clinical isolate Salmonella enterica serovar Typhimurium strain CVCC541. The minimum inhibitory concentration (MIC) of JH-3 against this bacterium was determined to be 100 μg/mL, which could decrease the number of CVCC541 cells by 1000-fold in vitro within 5 h. The transmission electron microscopy (TEM) results showed that JH-3 can damage the cell wall and membrane of CVCC541, leading to the leakage of cell contents and subsequent cell death. To measure the bactericidal activity of CVCC541-infected mice were treated intraperitoneally 40 or 10 mg/kg JH-3 at 2 h or 3 days postinfection. Our results showed that treatment with 40 mg/kg JH-3 at 2 h postinfection had the best therapeutic effect and could significantly protect mice from a lethal dose of CVCC541. Furthermore, the clinical symptoms, bacterial burden in blood and organs, and intestinal pathological changes were all decreased and were close to normal. This study examined the therapeutic effect of the antimicrobial peptide JH-3 against S. enterica CVCC541 infection for the first time and determined the therapeutic effect of different JH-3 doses and treatment times, laying the foundation for studies of new antimicrobial agents.

     

Circular RNA in renal diseases

Circular RNA (circRNA) is a newly described type of non‐coding RNA. Active research is greatly enriching the current understanding of the expression and role of circRNA, and a large amount of evidence has implicated circRNA in the pathogenesis of certain renal diseases, such as renal cell carcinoma, acute kidney injury, diabetic nephropathy and lupus nephritis. Studies have found evidence that circRNAs regulate programmed cell death, invasion, and metastasis and serve as biomarkers in renal diseases. Recently, circRNAs were identified in exosomes secreted by the kidneys. Nevertheless, the function of circRNA in renal diseases remains ambiguous. Given that circRNAs are regulators of gene expression, they may be involved in the pathology of multiple renal diseases. Additionally, emerging evidence is showing that circulating circRNAs may serve as novel biomarkers for renal disease. In this review, we have summarized the identification, biogenesis, degradation, and functions of circRNA and have evaluated the roles of circRNA in renal diseases.