云南省凤仙花属(凤仙花科)2新记录种

报道了云南省凤仙花科(Balsaminaceae)凤仙花属(Impatiens L.)植物2新记录,即睫毛萼凤仙花(I.blepharosepala Pritz.ex Diels)和红雉凤仙花(I.oxyanthera Hook.f.),并提供了形态描述及其图片,凭证标本保存于重庆三峡学院生命科学与工程学院植物标本馆。该报道的睫毛萼凤仙花花色为白色,红雉凤仙花植株茎、叶皆被微柔毛,茎有分枝,小枝细,丰富了2个物种的形态描述。     

Synthesis and detection of N-sulfonated oversulfated chondroitin sulfate in marketplace heparin

N-sulfonated oversulfated chondroitin sulfate (NS–OSCS), recently reported as a potential threat to the heparin supply, was prepared along with its intermediate derivatives. All compounds were spiked into marketplace heparin and subjected to United States Pharmacopeia (USP) identification assays for heparin (proton nuclear magnetic resonance [¹H NMR], chromatographic identity, % galactosamine [%GalN], anti-factor IIa potency, and anti-factor Xa/IIa ratio). The U.S. Food and Drug Administration (FDA) strong-anionic exchange high-performance liquid chromatography (SAX–HPLC) method resolved NS–OSCS from heparin and OSCS and had a limit of detection of 0.26% (w/w) NS–OSCS. The %GalN test was sensitive to the presence of NS–OSCS in heparin. Therefore, current USP heparin monograph tests (i.e., SAX–HPLC and %GalN) detect the presence of NS–OSCS in heparin.     

Construction of a chimeric lysin Ply187N-V12C with extended lytic activity against staphylococci and streptococci

Developing chimeric lysins with a wide lytic spectrum would be important for treating some infections caused by multiple pathogenic bacteria. In the present work, a novel chimeric lysin (Ply187N-V12C) was constructed by fusing the catalytic domain (Ply187N) of the bacteriophage lysin Ply187 with the cell binding domain (146-314aa, V12C) of the lysin PlyV12. The results showed that the chimeric lysin Ply187N-V12C had not only lytic activity similar to Ply187N against staphylococcal strains but also extended its lytic activity to streptococci and enterococci, such as Streptococcus dysgalactiae, Streptococcus agalactiae, Streptococcus pyogenes, Enterococcus faecium and Enterococcus faecalis, which Ply187N could not lyse. Our work demonstrated that generating novel chimeric lysins with an extended lytic spectrum was feasible through fusing a catalytic domain with a cell-binding domain from lysins with lytic spectra across multiple genera.     

Combined Serum Biomarkers in Non-Invasive Diagnosis of Non-Alcoholic Steatohepatitis

Background

Non-alcoholic steatoheaptitis (NASH), the critical stage of non-alcoholic fatty liver disease (NAFLD), is of chronic progression and can develop cirrhosis even hepatocellular carcinoma (HCC). However, non-invasive biomarkers for NASH diagnosis remain poorly applied in clinical practice. Our study aims at testing the accuracy of the combination of cytokeratin-18 M30 fragment (CK-18-M30), fibroblast growth factor 21 (FGF-21), interleukin 1 receptor antagonist (IL-1Ra), pigment epithelium-derived factor (PEDF) and osteoprotegerin (OPG) in diagnosing NAFLD and NASH.

Methods

179 patients with biopsy-proven NAFLD were enrolled as training group, 91 age- and gender-matched healthy subjects were recruited at the same time as controls. 63 other NAFLD patients were separately collected as validation group. 45 alcoholic fatty liver disease (AFLD) patients, 50 hepatitis B virus (HBV) patients, 52 hepatitis C virus (HCV) patients were also included. Serum biomarker levels were measured by enzyme-linked immunosorbent assay.

Results

Serum levels of CK-18-M30, FGF-21, IL-1Ra and PEDF increased, while OPG decreased in a stepwise fashion in controls, non-NASH NAFLD patients and NASH patients (P < 0.01). The area under receiver-operating characteristics curve to diagnose NASH was 0.86 for CK-18-M30, 0.89 for FGF-21, 0.89 for IL-1Ra, 0.89 for PEDF and 0.89 for OPG. CK-18-M30 had 70% negative predictive value (NPV) and 79% positive predictive value (PPV) to diagnose NASH. A 5-step approach measuring CK-18-M30 followed by FGF21, IL-1Ra, PEDF and OPG gradually improved the NPV to 76% and PPV to 85%, which reached 80% and 76% respectively in the validation cohort.

Conclusion

Compared to single biomarker, stepwise combination of CK-18-M30, FGF-21, IL-1Ra, PEDF and OPG can further improve the accuracy in diagnosing NASH.     

A fragmented aflatoxin-like gene cluster in the forest pathogen Dothistroma septosporum

The polyketide toxin dothistromin is very similar in structure to the aflatoxin precursor, versicolorin B. Dothistromin is made by a pine needle pathogen, Dothistroma septosporum, both in culture and in planta. Orthologs of aflatoxin biosynthetic genes have been identified that are required for dothistromin biosynthesis in D. septosporum. In contrast to the situation in aflatoxin-producing fungi where 25 aflatoxin biosynthetic and regulatory genes are tightly clustered in one region of the genome, the dothistromin gene cluster is fragmented. Three mini-clusters of dothistromin genes have been identified, each located on a 1.3-Mb chromosome and each grouped with non-dothistromin genes. There are no obvious patterns of repeated sequences or transposon relics to suggest recent recombination events. Most dothistromin genes within the mini-clusters are co-regulated, suggesting that coordinate control of gene expression is achieved despite this unusual arrangement of secondary metabolite biosynthetic genes.     

Piezo1 regulates migration and invasion of breast cancer cells via modulating cell mechanobiological properties

Cell migration and invasion are two essential processes during cancer metastasis. Increasing evidence has shown that the Piezo1 channel is involved in mediating cell migration and invasion in some types of cancers. However, the role of Piezo1 in the breast cancer and its underlying mechanisms have not been clarified yet. Here, we show that Piezo1 is high-expressed in breast cancer cell (BCC) lines, despite its complex expression in clinical patient database. Piezo1 knockdown (Piezo1-KD) promotes unconfined BCC migration, but impedes confined cell migration. Piezo1 may mediate BCC migration through the balances of cell adhesion, cell stiffness, and contractility. Furthermore, Piezo1-KD inhibits BCC invasion by impairing the invadopodium formation and suppressing the expression of metalloproteinases (MMPs) as well. However, the proliferation and cell cycle of BCCs are not significantly affected by Piezo1. Our study highlights a crucial role of Piezo1 in regulating migration and invasion of BCCs, indicating Piezo1 channel might be a new prognostic and therapeutic target in BCCs.     

拟南芥GHMP基因家族成员的组织表达及生物信息学分析

利用生物信息学方法获得拟南芥全基因组中12个GHMP基因家族成员。通过实时定量PCR技术研究这12个基因在不同组织中的表达,结果显示它们具有组织表达特异性。构建了拟南芥中GHMP基因家族成员的系统进化树。启动子区调控元件分析表明,大多数GHMP成员包含有光响应、生物钟及其它逆境胁迫响应的相关元件,预测这些GHMP基因家族成员可能参与了植物的光信号、生物钟及相关的逆境胁迫信号转导途径。     

缙云黄芩与伴生物种的种间关联度分析

缙云黄芩(Scutellaria tsinyunensis C.Y.Wu et Chow)是重庆特有濒危植物,也为极小种群物种。该研究采用2×2列联表、应用方差分析、χ~2统计量、Ochiai指数、Dice指数、Jaccard指数等计算方法,分析了缙云黄芩9个群落中草本层18种伴生物种与缙云黄芩的种间关联度,结合与其伴生物种的频度分布分析,以明确缙云黄芩及其伴生物种的频度分布及种间关联度,探讨其群落中主要草本物种与缙云黄芩的相互作用,为地方特有珍贵物种的保护和利用提供理论依据。结果表明:(1)缙云黄芩与其伴生物种在频度分布上与边缘鳞盖蕨以及蝴蝶花呈协同作用,与多序楼梯草、淡竹叶、蓝叶藤呈拮抗作用,与红盖鳞毛蕨部分呈协同作用、部分呈拮抗作用。(2)缙云黄芩群落总体关联度表明,6个群落呈现正关联,3个群落呈现负关联。(3)在48个种对中,34个种对显示为正关联,占总关联对数70.8%;14个种对之间表现为负关联,占总关联对数29.2%,其中显著正联结或负联结的种对仅3对,约占总数6.3%,极显著负联结种对仅1对。研究认为,寻找和保护与缙云黄芩正关联性较强的物种来共同形成利于特定物种生存的环境,或在野外将缙云黄芩移植到分布正关联物种的群落中有利于缙云黄芩野外扩繁。