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Known anoxygenic photosynthetic bacteria (APB) affiliated to Gammaproteobacteria usually use anaerobic metabolism and are restricted to oxygen-free habitats. Here, we report abundant (average of 34.5%) presence of diverse APB related to γ-like Proteobacteria in oxic oceanic surface water as indicated by the pufM gene, that encodes the M subunit of the light reaction centre complex. Thus, our sequences were most likely derived from aerobic anoxygenic phototrophs (AAnP). Two genetically distinct genotypes were revealed: one was from the oligotrophic North Pacific Ocean Gyre and the other, was from the trophic East China Sea and Bering Sea. The discovery of abundant presence of novel γ-like Proteobacterial pufM gene in the oxic seawater extends the functional ecotypes of AAnP. [ABSTRACT FROM AUTHOR]

Abstract: The abundance of aerobic anoxygenic phototrophic bacteria (AAPB), a new functional group that plays important roles in marine carbon cycling, is determined frequently by infrared epifluorescence microscopic analysis (IREM) or high-performance liquid chromatography (HPLC) based on detecting BChl a (bacteriochlorophyll a) fluorescence signal at 880 nm. Unfortunately, the fluorescence signal is often influenced by environmental variables and physiological state of cell. Here we developed a real-time quantitative PCR (qPCR) assay based on pufM gene to specifically quantify AAPB in marine environments. High specificity and sensitivity for estimation of AAPB abundance were revealed by analysis of amplification products, melting curves and target sequences. The phylogenetic tree indicated that this primer set is suitable for a wide genetic diversity of AAPB, including α-3, α-4 Proteobacteria and clones of unclear taxonomic position. In contrast, no amplicon was obtained from green non-sulphur bacteria and oxygenic phototrophic bacteria such as Cyanobacterial genomic DNA. The melting behavior could indicate predominant phenotypes in AAPB community in addition to validating the products of qPCR. The AAPB was estimated to range from 1.3×104 cell/ml to 3.4×105 cell/ml in our 10 tested water samples by this qPCR assay. Further investigations on the abundance distribution of AAPB in marine environments using the qPCR assay may provide new insight into their ecological functions. [Copyright &y& Elsevier]

The development of chemotherapeutic dug resistance hinders the clinical treatment of cancer. MicroRNAs (miRNAs/miRs) have been revealed to serve essential roles in the drug resistance of numerous types of cancer. miR-139-5p was previously reported to be associated with cisplatin (DDP) sensitivity in human nasopharyngeal carcinoma cells and colorectal cancer cells. However, the effect and underlying mechanism of miR-139-5p in DDP sensitivity in non-small cell lung cancer (NSCLC) cells has not yet been fully elucidated. In the present study, the expression of miR-139-5p and Homeobox protein Hox-B2 (HOXB2) in NSCLC tissues was examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. Subsequently, the effect of miR-139-5p on the DDP sensitivity of NSCLC cells in vitro was investigated. Cell proliferation was examined using a Cell Counting Kit-8 assay. Western blotting was used to evaluate the protein expression of HOXB2, phosphorylated (p)-PI3K, p-AKT, caspase-3 and cleaved-caspase-3, and RT-qPCR was used to evaluate the expression of miR-139-5p, and the mRNA expression levels of HOXB2, PI3K, AKT and caspase-3. The apoptotic rate of the cells was detected using flow cytometry. miR-139-5p expression in NSCLC tissues was shown to be significantly lower compared with that in adjacent tissues. Additionally, miR-139-5p increased cell apoptosis and inhibited NSCLC cell proliferation induced by DDP in vitro via modulating the PI3K/AKT/caspase-3 signaling pathway. Furthermore, HOXB2 was identified to be a target of miR-139-5p, and miR-139-5p was revealed to sensitize NSCLC cells to DDP via the targeting of HOXB2. Taken together, the results of the present study demonstrated that regulating the expression of miR-139-5p could provide a novel approach to reverse DDP resistance and increase chemosensitivity in the treatment of NSCLC. [ABSTRACT FROM AUTHOR]

Two colloidal gold immunochromatographic assays (CGIAs) for detection of EV71- and CA16- immunoglobulin M (IgM) were developed and evaluated. A total of 1465 sera collected from children with hand, foot, and mouth disease (HFMD), non-HFMD patients and healthy children. The sensitivity of IgM CGIA tests for EV71 and CA16 were 97.6% (330/338) and 91.6% (296/323) respectively, compared to those who were viral RNA positive by PCR. Their performances were comparable to those of commercial ELISA kits, with agreement of 98.1% for EV71-IgM and 97.3% for CA16-IgM. In addition, for EV71- and CA16-IgM CGIAs, the results of whole blood samples were 99.6% (248/249) and 100% (191/191) concordant to those with serum samples, respectively. As rapid point-of-care (POC) tests, the two CGIAs were suitable to be used in community clinic units, especially in resource-poor areas and will facilitate the control of HFMD. [ABSTRACT FROM AUTHOR]

Abstract: The baculovirus expression vector system (BEVS) is one of the most powerful methods for production of recombinant proteins for research or commercial purposes. Titration of viable virus in insect cell culture is often required when BEVS is used for basic research or bioprocessing. An enzyme-linked immunosorbent spot (ELISPOT) assay using monoclonal antibodies against the major capsid protein VP39 of both Autographa californica nuclear polyhedrosis virus (AcMNPV) and Bombyx mori nuclear polyhedrosis virus (BmNPV) was developed for baculovirus quantitation at 48h post-infection. The titer was determined by visualizing infected insect cells as blue spots and automated spot counting was achieved with ELISPOT hardware and software. Log-scale comparison of the results between the ELISPOT assay and a conventional end point dilution assay using a fluorescent marker showed a good correlation for both AcMNPV (R 2 =0.9980, p <0.05) and BmNPV (R 2 =0.9834, p <0.05). In conclusion, a novel, rapid and semi-automated procedure for titrating baculovirus was developed based on the specific immunostaining of infected cells followed by automated spot counting. [Copyright &y& Elsevier]

Abstract: A sub-library based on peptide mimic 125 was designed and constructed, and 18 phagotopes specifically binding 8H5mAb were isolated. Antisera against three phagotopes, containing peptide 12MH-1, 12MH-5 and 12MH-8 reacted with 3 different H5N1 virus strains, but not with 2 H1N1 and 2 H3N2 viruses by Dot blots. The affinity of 12MH-8 was approximately eight times more than 12MH-1 or 12MH-5 or parent peptide 125. Furthermore, synthesized 12MH-1 and 12MH-8 could block the 8H5mAb binding with 4 H5N1 virus strains via hemagglutinin inhibition. These results suggest that these 3 mimotopes closely mimics the native 8H5 epitopes. [ABSTRACT FROM AUTHOR]

Examines the physiological and ecological features of aerobic anoxygenic phototrophic bacteria (AAPB). Roles of AAPB in the marine ecosystems; Cell division of mother AAPB; Bacteriochlorophyll found in AAPB.