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101.
102.
High throughput sequencing of 16S rRNA gene leads us into a deeper understanding on bacterial diversity for complex environmental samples, but introduces blurring due to the relatively low taxonomic capability of short read. For wastewater treatment plant, only those functional bacterial genera categorized as nutrient remediators, bulk/foaming species, and potential pathogens are significant to biological wastewater treatment and environmental impacts. Precise taxonomic assignment of these bacteria at least at genus level is important for microbial ecological research and routine wastewater treatment monitoring. Therefore, the focus of this study was to evaluate the taxonomic precisions of different ribosomal RNA (rRNA) gene hypervariable regions generated from a mix activated sludge sample. In addition, three commonly used classification methods including RDP Classifier, BLAST-based best-hit annotation, and the lowest common ancestor annotation by MEGAN were evaluated by comparing their consistency. Under an unsupervised way, analysis of consistency among different classification methods suggests there are no hypervariable regions with good taxonomic coverage for all genera. Taxonomic assignment based on certain regions of the 16S rRNA genes, e.g. the V1&V2 regions – provide fairly consistent taxonomic assignment for a relatively wide range of genera. Hence, it is recommended to use these regions for studying functional groups in activated sludge. Moreover, the inconsistency among methods also demonstrated that a specific method might not be suitable for identification of some bacterial genera using certain 16S rRNA gene regions. As a general rule, drawing conclusions based only on one sequencing region and one classification method should be avoided due to the potential false negative results. 相似文献
103.
Wei Wang Mei Zhang Weimin Sun Shanmin Yang Ying Su Hengshan Zhang Chaomei Liu Xinfeng Li Ling Lin Sunghee Kim Paul Okunieff Zhenhuan Zhang Lurong Zhang 《PloS one》2013,8(10)
Most human pancreatic cancer cells are resistant to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. However, the mechanisms by which pancreatic cancer cells utilize their extracellular molecules to counteract the proapoptotic signaling mediated by the TNF family are largely unknown. In this study, we demonstrate for the first time that DcR3, a secreted decoy receptor that malignant pancreatic cancer cells express at a high level, acts as an extracellular antiapoptotic molecule by binding to TRAIL and counteracting its death-promoting function. The reduction of DcR3 with siRNA unmasked TRAIL and greatly enhanced TRAIL-induced apoptosis. Gemcitabine, a first-line drug for pancreatic cancer, also reduced the level of DcR3. The addition of DcR3 siRNA further enhanced gemcitabine-induced apoptosis. Notably, our in vivo study demonstrated that the therapeutic effect of gemcitabine could be enhanced via further reduction of DcR3, suggesting that downregulation of DcR3 in tumor cells could tip the balance of pancreatic cells towards apoptosis and potentially serve as a new strategy for pancreatic cancer therapy. 相似文献
104.
Young Ju Lee Gyeong Bok Jung Samjin Choi Gihyun Lee Ji Hye Kim Ho Sung Son Hyunsu Bae Hun-Kuk Park 《PloS one》2013,8(11)
Cyanoacrylate (CA) is most widely used as a medical and commercial tissue adhesive because of easier wound closure, good cosmetic results and little discomfort. But, CA-based tissue adhesives have some limitations including the release of cytotoxic chemicals during biodegradation. In previous study, we made prepolymerized allyl 2-CA (PACA) based tissue adhesive, resulting in longer chain structure. In this study, we investigated a biocompatibility of PACA as alternative tissue adhesive for medical application, comparing with that of Dermabond® as commercial tissue adhesive. The biocompatibility of PACA was evaluated for short-term (24 hr) and long-term (3 and 7 days) using conventional cytotoxicity (WST, neutral red, LIVE/DEAD and TUNEL) assays, hematoxylin-eosin (H&E) and Masson trichrome (MT) staining. Besides we examined the biochemical changes in cells and DNA induced by PACA and Dermabond® utilizing Raman spectroscopy which could observe the denaturation and conformational changes in protein, as well as disintegration of the DNA/RNA by cell death. In particular, we analyzed Raman spectrum using the multivariate statistical methods including principal component analysis (PCA) and support vector machine (SVM). As a result, PACA and Dermabond® tissue adhesive treated cells and tissues showed no difference of the cell viability values, histological analysis and Raman spectral intensity. Also, the classification analysis by means of PCA-SVM classifier could not discriminate the difference between the PACA and Dermabond® treated cells and DNA. Therefore we suggest that novel PACA might be useful as potential tissue adhesive with effective biocompatibility. 相似文献
105.
Huiyun Li Ye Liu Sumei Chen Jiafu Jiang Aiping Song Weimin Fang Fadi Chen 《Phyton》2020,89(4):851-859
Black spot disease, caused by the necrotrophic fungus Alternaria
tenuissima (Fr.) Wiltsh (A. tenuissima), is considered a highly destructive disease
of Chrysanthemum (Chrysanthemum morifolium Ramat.). A set of 17 accessions
of commercial chrysanthemum cultivars were evaluated for resistance to A.
tenuissima by seedling artificial inoculation. It was found that the reaction of
the accessions to artificial inoculation ranged from resistant to highly susceptible.
Five varieties of chrysanthemum (‘Zhongshan Taogui’, ‘Jinba’, ‘Zhongshan Jinguan’, ‘Jinling Wanhuang’ and ‘Jinling Yangguang’) were resistant; two varieties
of chrysanthemum (‘Zhongshan Xinggui’ and ‘Zhongshan Jinkui’) were moderately resistant; and others were susceptible to various degrees, four varieties of
chrysanthemum (‘Zhongshan Zihe’, ‘Zhongshan Jiuhong’, ‘Zaoyihong’ and ‘Jinling Jiaohuang’) were highly susceptible, especially. Some leaf morphological features of two resistant and two highly susceptible cultivars were further researched.
Trichome density, length, height, gland size and stomata density were found to be
associated with plant passive resistance. Resistant varieties that were identified in
present study will be promising germplasm for exploitation of breeding programmes aimed at developing A. tenuissima-resistant cultivars and increasing
genetic diversity. 相似文献
106.
Kumar P. S. Ling C. Y. Zhou Z. B. Dong Y. L. Sun C. L. Song Y. X. Wong N. K. Ju J. H. 《Microbiology》2020,89(4):483-492
Microbiology - Marine actinobacteria particularly from marine environments are believed to be inexhaustible sources of biologically active molecules for biomedical and industrial applications. We... 相似文献
107.
Ju Wen Sun Tiantian Lu Wenyi Smith Alhaji Osman Bao Yurong Adzraku Seyram Yao Qi Kunming Xu Kailin Qiao Jianlin Zeng Lingyu 《Molecular biology reports》2020,47(4):2735-2748
Molecular Biology Reports - Murine bone marrow-derived macrophages (M0) and M1- and M2-polarized macrophages are being widely used as a laboratory model for polarized macrophages related molecular... 相似文献
108.
109.
Chengdi Wang Wenliang Qiao Yuting Jiang Min Zhu Jun Shao Tao Wang Dan Liu Weimin Li 《Journal of cellular physiology》2020,235(5):4913-4927
110.
M. V. Kireev N. S. Medvedeva A. D. Korotkov Ju. I. Polyakov A. D. Anichkov S. V. Medvedev 《Human physiology》2013,39(1):54-57
In this article, the characteristics of the functional activity of the anterior cingulate cortex (ACC), a key element of the neuroanatomical error detection system of the brain in drug-resistant forms of obsessive-compulsive disorder (OCD) are discussed on the basis of both original and published data. Available data indicate the presence of a functional deficit zone in the ACC during PCD. This fact suggests that the functions of the ACC in OCD patients are partially redistributed between other brain areas. Thus, in contrast to the previously accepted ideas, the target of stereotactic surgery for OCD is a pathologically altered brain region. Probably, this explains the fact that the operation does not lead to significant changes in the patient’s psyche. The pathological reorganization of the functional activity of the brain in OCD remains unclear and requires further investigation. 相似文献