小果蔷薇的花粉形态及营养成份分析

对小果蔷薇的花粉形态及纹饰进行观察,并分析测定其营养成份。各种营养含量为：总氮２．７３％,蛋白质１７．１１％,还原糖２１．７５％,可溶性糖２２.４％,氨基酸总量２９．８５％,必需氨基酸的构成比例与ＦＡＯ／ＷＨＯ的建议值接近,维生素和微量元素的含量亦较丰富,是具有开发利用价值的天然高级营养源。     

增温对长白山苔原植物叶片和土壤矿质元素含量的影响

温度变化会影响植物对养分的吸收以及自身养分含量变化,尤其对长期处于低温条件下的苔原植物。采用开顶箱增温法,研究了1个生长季增温对长白山苔原3种代表植物——牛皮杜鹃(Rhododendron aureum Pall)、笃斯越桔(Vaccinium uliginosum)和东亚仙女木(Dryas octopetala var.asiatica)叶片及土壤矿质元素钾(K)、铝(Al)、铜(Cu)、铁(Fe)、镁(Mg)、锰(Mn)、锌(Zn)和钙(Ga)含量的影响。结果表明:1)增温明显改变了土壤矿质元素含量,使土壤Fe、Al和K含量分别增加0.44%、2.76%和4.88%,而Cu、Mg、Mn、Zn和Ga含量分别降低2.63%、5.07%、7.46%、21.95%和15.60%;2)整个生长季,增温使牛皮杜鹃叶K含量增加8.17%,且具有明显的月变化,其叶Mg和Mn含量也分别比对照组高66.39%和14.73%;3)与对照相比,增温使笃斯越桔叶K、Al和Zn含量分别增加15.24%、5.45%和87.45%,生长季不同月份,其叶K、Al、Mg、Mn、Zn和Ga含量差异明显;4)增温并没有明显改变东亚仙女木叶片各矿质元素含量,但其叶K、Cu和Ga含量具有明显月波动。因此,不同物种矿质元素含量变化对增温的响应方式不同,增温对苔原植物的影响也存在一定的物种差异性。     

一次性细菌药敏测定装置的研制

为了适应临床依靠药敏试验而指导临床选择用药的快速要求,我们研制的一次性细菌M IC 测定装置,以确保药敏试验结果的准确性。一次性细菌的M IC 测定装置经国际标准菌株的检测,结果证实这些国际标准菌株的M IC 都在允许范围内,由此验证一次性细菌M IC 测定装置是可靠的,这种装置还具有易读、重复性好的特点,在完成M IC 检测后还可以进行M BC 的检测,值得临床推广使用     

Purification and Identification of Pine Nut (Pinus yunnanensis Franch.) Protein Hydrolysate and Its Antioxidant Activity in Vitro and in Vivo

In this study, the pine nut (Pinus yunnanensis Franch.) protein was hydrolyzed by alkaline protease and trypsin to prepare pine nut protein hydrolysate (PNPH). The chemical, intracellular and in vivo antioxidant capacity of PNPH were evaluated. PNPH owned the ability of scavenging free radicals, and it could protect the HepG2 cells from oxidative damage by preserving cell viability. Moreover, PNPH could reduce the malondialdehyde (MDA) content and improved the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in serum, heart and liver of aging mice induced by D-galactose. Further, the PNPH was stepwise purified and identified, and 15 peptides were identified from purified fraction in PNPH. The three-dimension structures of identified peptides were predicted. Among all identified peptides, peptide 3, 7, 8 and 11 were presumed to possess good antioxidant activity. Overall, PNPH and purified peptides isolated from PNPH have potential application prospects in the field of natural antioxidants and anti-aging functional foods.     

The C-terminal portion of the nucleocapsid protein demonstrates SARS-CoV antigenicity

In order to develop clinical diagnostic tools for rapid detection of SARS-CoV (severe acute respiratory syndrome-associated coronavirus) and to identify candidate proteins for vaccine development, the C-terminal portion of the nucleocapsid (NC) gene was amplified using RT-PCR from the SARS-CoV genome, cloned into a yeast expression vector (pEGH), and expressed as a glutathione S-transferase (GST) and Hisx6 double-tagged fusion protein under the control of an inducible promoter. Western analysis on the purified protein confirmed the expression and purification of the NC fusion proteins from yeast. To determine its antigenicity, the fusion protein was challenged with serum samples from SARS patients and normal controls. The NC fusion protein demonstrated high antigenicity with high specificity, and therefore, it should have great potential in designing clinical diagnostic tools and provide useful information for vaccine development.     

篮状菌属二个中国新记录种

【背景】调查我国滩涂土壤可培养真菌物种多样性,丰富我国真菌物种资源。【目的】报道我国篮状菌属2个产子囊孢子的新记录种。【方法】采用形态学和基于β-微管蛋白基因部分序列和rDNA ITS1-5.8S-ITS2序列系统学的多相分类学方法。【结果】分离鉴定出3种有性型篮状菌,即阿根廷篮状菌Talaromyces argentinensis （ZZ2-7-1h=CGMCC 3.16171）、巴塞篮状菌Talaromyces barcinensis （ZZ2-1-1=CGMCC 3.16172）和乌克兰篮状菌Talaromyces ucrainicus（JS11-5=CGMCC 3.16173）,其中前2种为我国新记录种。阿根廷篮状菌在25℃生长适度,在37℃生长局限,形成絮状兼绳状菌落,其菌丝体白色夹杂浅粉色,产生稀少的橙黄色裸囊壳和壁具细密小刺的椭球形子囊孢子。巴塞篮状菌在25℃生长适度,在37℃不生长,形成绒状菌落,其菌丝体为白色兼黄色,裸囊壳稀少,较小,呈皮黄色,子囊孢子椭球形,壁具稀疏小刺。【结论】参考我国迄今已报道的篮状菌物种,确定阿根廷篮状菌和巴塞篮状菌为我国篮状菌属的新记录种。     

MRCQuant- an accurate LC-MS relative isotopic quantification algorithm on TOF instruments

Background  

Relative isotope abundance quantification, which can be used for peptide identification and differential peptide quantification, plays an important role in liquid chromatography-mass spectrometry (LC-MS)-based proteomics. However, several major issues exist in the relative isotopic quantification of peptides on time-of-flight (TOF) instruments: LC peak boundary detection, thermal noise suppression, interference removal and mass drift correction. We propose to use the Maximum Ratio Combining (MRC) method to extract MS signal templates for interference detection/removal and LC peak boundary detection. In our method, MRCQuant, MS templates are extracted directly from experimental values, and the mass drift in each LC-MS run is automatically captured and compensated. We compared the quantification accuracy of MRCQuant to that of another representative LC-MS quantification algorithm (msInspect) using datasets downloaded from a public data repository.     

A novel fluorescent assay for oxytetracycline hydrochloride based on fluorescence quenching of water‐soluble CdTe nanocrystals

A novel assay for oxytetracycline hydrochloride (OTC) based on fluorescence quenching was developed from the interaction between functionalized cadmium telluride quantum dots (CdTe QDs) and OTC. Optimum conditions for the detection of OTC were found after investigating all factors. Under optimum conditions, luminescence of CdTe nanocrystals (λ_ex = 365 nm, λ_em = 562 nm) was quenched by OTC in a concentration‐dependent manner best described by a modified Stern‐Volmer type equation. Good linearity was obtained with a regression coefficient of 0.9999 in the range of 1.34 ~ 13.4 x 10^‐5 mol/L and a limit of detection of 3.08 x 10^‐7 mol/L. In addition, the quenching mechanism was also established. The results imply that the close proximity of OTC‐CdTe was driven by electrostatic attraction and the resulting effective electron transfer from OTC to QDs could be responsible for fluorescence quenching of CdTe‐QDs. Copyright © 2012 John Wiley & Sons, Ltd.     

Study on the fluorescence resonance energy transfer between CdS quantum dots and Eosin Y

Water‐soluble CdS quantum dots (QDs) were prepared using mercaptoacetic acid (TGA) as the stabilizer in an aqueous system. A fluorescence resonance energy transfer (FRET) system was constructed between water‐soluble CdS QDs (donor) and Eosin Y (acceptor). Several factors that impacted the fluorescence spectra of the FRET system, such as pH (3.05–10.10), concentration of Eosin Y (2–80 mg/L) and concentration of CdS QDs (2–80 mg/L), were investigated and refined. Donor‐to‐acceptor ratios, the energy transfer efficiency (E) and the distance (r) between CdS QDs and Eosin Y were obtained. The results showed that a FRET system could be established between water‐soluble CdS QDs and Eosin Y at pH 5.0; donor‐to‐acceptor ratios demonstrated a 1: 8 proportion of complexes; the energy transfer efficiency (E) and the distance (r) between the QDs and Eosin Y were 20.07% and 4.36 nm,respectively. Copyright © 2014 John Wiley & Sons, Ltd.     

Facile synthesis of AgNPs@SNCDs nanocomposites as a fluorescent ‘turn on’ sensor for detection of glutathione

The present study illustrates the facile synthesis of silver nanoparticles capped with sulfur and nitrogen co‐doped carbon dots (AgNPs@SNCDs) nanocomposites and their application towards the sensitive and selective detection of glutathione (GSH) using a spectrofluorimetry method. SNCDs were synthesized using solvothermal treatment of cysteamine hydrochloride and p‐phenylenediamine. The as‐fabricated SNCDs were then utilized as capping and stabilizing agents for the preparation of AgNPs@SNCDs nanocomposites using wet chemistry. The size of AgNPs@SNCDs nanocomposites was characterized to be ~37.58 nm or even larger aggregates. Particularly, the quenched fluorescence of AgNPs@SNCDs nanocomposites could be significantly restored upon addition of GSH, and the colour of its solution changed to some extent. The fluorescence intensity ratio of AgNPs@SNCDs nanocomposites at ~450 nm and 550 nm was directly proportional to the GSH concentration within the ranges 8.35–66.83 μM and 66.83–200.5 μM, and the detection limit was 0.52 μM. Furthermore various common organic molecules had no obvious interference in the detection mode. The proposed nanosensor was successfully applied for GSH assay in actual water samples.