Accumulation of enteric bacteriophage in fresh water sediments

Our study aimed to assess the accumulation of bacteriophages in sandy and clayey fresh water sediments. All of the 24 natural fresh water sediments were positive for somatic and F-specific phages, though their concentrations in the overlying water were undetectable in 1 and 11 samples, respectively, out of 24, corresponding to 4 and 46% for somatic and F-specific phages, respectively. Based on the sediment-to-water ratios, F-specific phages accumulate over 100 times more than the somatic coliphages in clayey sediments. Inactivation of bacteriophages in clayey and sandy sediments over a 1-month period at 15°C was negligible. Our data suggest that persistence of deposited viruses in fresh water sediments leads to accumulation and the findings call for additional investigations on the fate of entrapped pathogenic viruses.     

Presenting graphical information

This article outlines the mistakes that are commonly made when data are presented graphically. Common errors when displaying data are highlighted, and preferred solutions for avoiding these mistakes are described. The preferred approaches form the requirements that authors should meet when submitting papers to the journal of Pediatric Allergy and Immunology.     

微机化程控心脏刺激仪的研制

介绍了一种全微机化的程控心脏刺激仪系统。利用微机可视化界面可以方便地设备各项刺激参数并实现所有的刺激控制功能。同时，状态参数和波形的实时监测显示窗口更进一步地提高了临床应用的直观性和有效性。经初步实现表现，该系统较以往的程控心脏刺激仪而言，通过性强、操作简单并且实时监测功能完善，在临床电生理治疗中具有明显的应用价值。     

测定计算机显示器的X线辐射剂量

目的 测定计算机显示器的Ｘ线剂量水平。方法 采用高灵敏ＬｉＦ（Ｍｇ．Ｃｕ．Ｐ）热释光剂量计对计算机显示器表面及附加防护屏（网）后的Ｘ线辐射剂量进行累积剂量监测。结果 计算机显示器表面的平均照射量为０．９３Ｒ／ｄ，在屏（网）岸一是０．２４ｍＲ／ｄ。结论 计算机产生的低能和低水平Ｘ线辐射剂量未超过有关规定标准。     

IDENTIFICATION OF DRUG RESISTANT RELATED cDNA IN LUNG ADENOCARCINOMA CELL LINES

The mechanisms of multidrug resistance (MDR) in lung cancer are complicated, and have not yet been elucidated completely. Studies showed that clinical MDR in lung cancer can only be explained partially by known MDR related proteins1-3. Our previous study also supported this conclusion4. Therefore, in order to clarify the development mechanisms of drug resistance in lung cancer it would be helpful to identify new drug resistance genes and explore their structure and function. In this study,…     

Molecular Mimetics of Neisseria meningitidis Serogroup B Polysaccharide

Strains of Neisseria meningitidis serogroup B (NmB) are an important cause of meningitis and sepsis. Efforts to develop a NmB vaccine have been hampered by poor immunogenicity of the polysaccharide capsule, which cross-reacts with host polysialic acid, and the danger of eliciting autoantibodies. To investigate the potential of molecular mimetics to circumvent these problems, we prepared murine monoclonal antibodies (mAbs) against the N-propionyl derivative (N-Pr) of NmB polysaccharide [10]. Several mAbs were found that reacted with capsular polysaccharide epilopes, which were distinct from host polysialic acid. These mAbs also passively conferred protection against experimental bacteremia. We used these mAbs to screen novel independently folding peptide phage display libraries, and pools of combinatorial small molecules, each consisting of-30 to-700 small molecules of diverse composition. To date, several mimetic candidates have been identified. One is a peptide selected from a library of independently folding αβ peptides, and others are peptoid [23] dimers or trimers selected from the small molecule pools. The peptoids contain an indan-type of ring system, and some of them also contain a large hydrophobic group such as oleyl amine or dehydroabietyl amine, and a positively charged group at the amino-terminus. Both the αβ peptide from the phage library, and the peptoids from the small molecule pools, inhibit binding of the mAbs to N-Pr NmB polysaccharide. Future studies will focus on the structure/activity relationship of these mimetics, and the development of immunogens that may be capable of eliciting anti-capsular antibody without autoantibody activity.     

利用噬菌体展示技术制备人血管生成素2单链抗体

目的 用纯化的人血管生成素2(Ang2)蛋白,通过噬菌体展示技术从非免疫小鼠噬菌体展示抗体库中淘选、鉴定Ang2单链抗体.方法 以纯化的人Ang2蛋白为抗原,对非免疫小鼠噬菌体展示抗体库进行富集和筛选,获得Ang2单链抗体,利用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)和Western blot法检测目的蛋白的表达并测序.结果 经过3轮富集和筛选,获得了1个能特异性识别Ang2蛋白的阳性噬菌体克隆,DNA测序表明其含有完整的单链抗体基因片段,大小约750 bp,表达蛋白相对分子质量约33.7×103；通过SDS-PAGE进一步实现Ang2单链抗体(phage-Ang2-scFv)的鉴定.结论 成功分离并鉴定人Ang2-scFv,为进一步的功能学研究奠定了基础.     

Functionalization of carbon nanomaterials by evolutionary molecular engineering: Potential application in drug delivery systems

By virtue of the progress made in evolutionary molecular engineering, peptide aptamers that specifically recognize target molecules are now routinely created using a peptide phage display system. The system was originally developed for isolating peptides that specifically recognized biomacromolecules (e.g. proteinous receptors), but are now also being used to acquire peptide motifs that bind to inorganic materials, such as semiconductors, metals and carbon nanomaterials. We have created the peptide aptamer against carbon nanohorns, a vesicular carbon nanomaterial whose size is 80–100 nm in diameter. By combining the peptide motif that has affinity to the surfaces of carbon nanohorns with peptide aptamers that can target specific organs, we can functionalize the carbon nanomaterial to provide novel types of carriers for drug delivery systems.     

Evaluation of two oxygen analyzers by computerized data acquisition and processing

Monitoring of inspired oxygen concentration during anesthesia with nitrous oxide is becoming accepted as essential. This type of monitoring demands accurate monitors that respond rapidly. We evaluated two such devices for their response patterns to rapid changes in oxygen concentration, a galvanic or “fuel cell” unit and a polarographic device. Data were stored after analog-to-digital conversion. The response patterns to stepwise changes in nitrous oxide and oxygen mixtures were recorded at flow rates ranging from 2 to 10 L/min. Both units responded accurately to all changes in the absolute oxygen concentration; the polarographic unit was, on average, twice as fast. Responsiveness to nitrous oxide was low (<0.4% at 100% nitrous oxide), and the stability of the signals was good. The 90% response time (T₉₀) was consistent for any stepwise increase or decrease in oxygen concentration between 0, 21, 33, 50, and 100%. After a step change from 0 to 100% oxygen at a gas flow rate of 10 L/min, the T₉₀ was 5.8 seconds in the polarographic device and 11.4 seconds in the galvanic device (p<0.01). After a decrease from 100 to 0% oxygen, the T₉₀ was 0.6 second longer in both monitors. Comparing flow rates of 2 L/min with 10 L/min, the T₉₀ was delayed by 1.1 and 2.3 seconds for an increase, and by 1.4 and 2.9 seconds for a decrease in oxygen concentration. Experimental data suggest that both sensors respond adequately during routine clinical use. The faster response of the polarographic device is probably of limited clinical relevance, but it may aid in calibration.     

Human inhalable antibody fragments neutralizing SARS-CoV-2 variants for COVID-19 therapy

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