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81.
Phan VK Nguyen XC Nguyen XN Vu KT Ninh KB Chau VM Bui HT Truong NH Lee SH Jang HD Kim YH 《Bioorganic & medicinal chemistry letters》2011,21(2):633-637
By bioactive-guided fractionation of methanol extract of the Ficus microcarpa leaves, one new C-glucosylflavone, ficuflavoside (1), one new megastigmane glycoside, ficumegasoside (8), and twelve known compounds including flavonoids (2-6), phenylpropanoids (7), megastigmanes (9-11) and sterol derivatives (12-14) were isolated. Their chemical structures were elucidated by mass, 1D, and 2D NMR spectroscopies. The antioxidant activities of these compounds were measured using the oxygen radical absorbance capacity methods. Compounds 1-6 exhibited potent antioxidant activities of 6.6-9.5 μM Trolox equivalents at the concentration of 2.0 μM. The results indicated 2, 3, and 5 having meaningful reducing capacity of copper (I) ions concentration of 6.1-8.4 μM. 相似文献
82.
Sheath blight infection of rice by Rhizoctonia solani Kühn AG1-IA often results in serious yield losses in intensive rice cultivation. Biological control agents (BCAs) have previously
been isolated but poor efficiency is often observed when applied under field conditions. This study compares a traditional
dual-culture plate assay and a new water-surface microcosm assay for isolation of antagonistic soil bacteria. In the water-surface
microcosm assay, floating pathogen mycelium is used as a source for isolation of hyphae-colonizing soil bacteria (HCSB), which
are subsequently screened for antagonism. Ten antagonistic soil bacteria (ASB) isolated from a variety of Vietnamese rice
soils using dual-culture plates were found to be affiliated with Bacillus based on 16S rRNA gene sequencing. However, all the ASB isolates grew poorly and showed no antagonism in the water-surface
microcosm assay. In contrast, 11 (out of 13) HCSB isolates affiliated with Burkholderia sp. all grew well by colonizing the hyphae in the microcosms. Two of the Burkholderia sp. isolates, assigned to B. vietnamiensis based on recA gene sequencing, strongly inhibited fungal growth in both the dual-culture and water-surface microcosm assays; HCSB isolates
affiliated to other species or species groups showed limited or no inhibition of R. solani in the microcosms. Our results suggest that HCSB obtained from floating pathogen hyphae can be a new source for isolation
of efficient BCAs against R. solani, as the isolation assay mimics the natural habitat for fungal-bacterial interaction in the fields. 相似文献
83.
Nguyen CQ Gao JH Kim H Saban DR Cornelius JG Peck AB 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(1):382-390
NOD.B10-H2(b) and NOD/LtJ mice manifest, respectively, many features of primary and secondary Sj?gren's syndrome (SjS), an autoimmune disease affecting primarily the salivary and lacrimal glands leading to xerostomia (dry mouth) and xerophthalmia (dry eyes). B lymphocytes play a central role in the onset of SjS with clinical manifestations dependent on the appearance of autoantibodies reactive to multiple components of acinar cells. Previous studies with NOD.IL4(-/-) and NOD.B10-H2(b).IL4(-/-) mice suggest that the Th2 cytokine, IL-4, plays a vital role in the development and onset of SjS-like disease in the NOD mouse model. To investigate the molecular mechanisms by which IL-4 controls SjS development, a Stat6 gene knockout mouse, NOD.B10-H2(b).C-Stat6(-/-), was constructed and its disease profile was defined and compared with that of NOD.B10-H2(b).C-Stat6(+/+) mice. As the NOD.B10-H2(b).C-Stat6(-/-) mice aged from 4 to 24 wk, they exhibited leukocyte infiltration of the exocrine glands, produced anti-nuclear autoantibodies, and showed loss and gain of saliva-associated proteolytic enzymes, similar to NOD.B10-H2(b).C-Stat6(+/+) mice. In contrast, NOD.B10-H2(b).C-Stat6(-/-) mice failed to develop glandular dysfunction, maintaining normal saliva flow rates. NOD.B10-H2(b).C-Stat6(-/-) mice were found to lack IgG1 isotype-specific anti-muscarinic acetylcholine type-3 receptor autoantibodies. Furthermore, the IgG fractions from NOD.B10-H2(b).C-Stat6(-/-) sera were unable to induce glandular dysfunction when injected into naive recipient C57BL/6 mice. NOD.B10-H2(b).C-Stat6(-/-) mice, like NOD.B10-H2(b).IL4(-/-) mice, are unable to synthesize IgG1 Abs, an observation that correlates with an inability to develop end-stage clinical SjS-like disease. These data imply a requirement for the IL-4/STAT6-pathway for onset of the clinical phase of SjS-like disease in the NOD mouse model. 相似文献
84.
Cuong NL 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2007,65(2):129-135
The discovery of a female skeleton is reported, which can be ascribed to the Hoa Binh civilization, existing about 10,000 years before now. The most remarkable fact concerning this finding is the existence of seashells (Cyprea arabica), which were found in the eye sockets. The reasons for this in Southeast Asia so far unique burial practice are discussed. 相似文献
85.
86.
Linh Nguyen Thi Nhat Cuong Le Kim Tam Ho Thanh Tung Hoang Thanh Luan Vu Quoc Hien Vu Thi Loc Nguyen Hoang Nhut Duong Tan 《Plant Cell, Tissue and Organ Culture》2019,136(1):101-108
Plant Cell, Tissue and Organ Culture (PCTOC) - The effects of l-alanine and its derivatives on cephalotaxine production of Cephalotaxus mannii suspension cultures were investigated in this paper.... 相似文献
87.
Pham CA Jung SJ Phung NT Lee J Chang IS Kim BH Yi H Chun J 《FEMS microbiology letters》2003,223(1):129-134
A facultative anaerobic bacterium was isolated from a mediator-less microbial fuel cell fed with artificial wastewater containing acetate and designated as PA3. The isolate was identified as a strain of Aeromonas hydrophila based on its biochemical, physiological and morphological characteristics as well as 16S rDNA sequence analysis and DNA-DNA hybridization. PA3 used glucose, glycerol, pyruvate and hydrogen to reduce Fe(III), nitrate and sulfate. Cyclic voltammetry showed that PA3 was electrochemically active and was the culture collection strain A. hydrophila KCTC 2358. Electricity was generated from a fuel cell-type reactor, the anode compartment of which was inoculated with cell suspensions of the isolate or A. hydrophila KCTC 2358. The electrochemical activities are novel characteristics of A. hydrophila. 相似文献
88.
Hongen Yin Cuong Q Nguyen Yuval Samuni Toshimitsu Uede Ammon B Peck John A Chiorini 《Arthritis research & therapy》2012,14(1):R40-11
Introduction
Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is a key negative costimulatory molecule that displays a wide range of anti-inflammatory properties and is currently approved to treat rheumatoid arthritis as a recombinant fusion protein (CTLA4IgG). To better understand the role of CTLA4IgG in primary Sjögren's syndrome (pSS), we generated a recombinant adeno-associated virus vector serotype 2 (AAV2) expressing a chimera of mouse CTLA-4 fused with a human immunoglobulin (AAV2-CTLA4IgG) and observed the effect of this molecule in C57BL/6.NOD-Aec1Aec2 mice, an animal model of pSS.Methods
A recombinant adeno-associated virus-2 (AAV-2) vector was constructed encoding a CTLA4IgG fusion protein. The AAV2-CTLA4IgG vector and an AAV2 control vector encoding beta galactosidase (LacZ) were administered by retrograde cannulation of the submandibular glands of C57BL/6.NOD-Aec1Aec2 mice. Protein expression was measured by ELISA and salivary glands were assessed for inflammation and activity.Results
Recombinant CTLA4IgG blocked B7 expression on macrophages in vitro. In vivo, localized expression of CTLA4IgG in the salivary glands of C57BL/6.NOD-Aec1Aec2 mice inhibited the loss of salivary gland activity and decreased T and B cell infiltration as well as dendritic cells and macrophages in the glands compared with control mice. In addition a decrease in several proinflammatory cytokines and an increase in transforming growth factor beta-1 (TGF-β1) expression were also observed.Conclusions
These data suggest expression of CTLA4IgG in the salivary gland can decrease the inflammation and improve the xerostomia reported in these mice. 相似文献89.
Linus Bengtsson Xin Lu Quoc Cuong Nguyen Martin Camitz Nguyen Le Hoang Tuan Anh Nguyen Fredrik Liljeros Anna Thorson 《PloS one》2012,7(11)
Objective
Lack of representative data about hidden groups, like men who have sex with men (MSM), hinders an evidence-based response to the HIV epidemics. Respondent-driven sampling (RDS) was developed to overcome sampling challenges in studies of populations like MSM for which sampling frames are absent. Internet-based RDS (webRDS) can potentially circumvent limitations of the original RDS method. We aimed to implement and evaluate webRDS among a hidden population.Methods and Design
This cross-sectional study took place 18 February to 12 April, 2011 among MSM in Vietnam. Inclusion criteria were men, aged 18 and above, who had ever had sex with another man and were living in Vietnam. Participants were invited by an MSM friend, logged in, and answered a survey. Participants could recruit up to four MSM friends. We evaluated the system by its success in generating sustained recruitment and the degree to which the sample compositions stabilized with increasing sample size.Results
Twenty starting participants generated 676 participants over 24 recruitment waves. Analyses did not show evidence of bias due to ineligible participation. Estimated mean age was 22 years and 82% came from the two large metropolitan areas. 32 out of 63 provinces were represented. The median number of sexual partners during the last six months was two. The sample composition stabilized well for 16 out of 17 variables.Conclusion
Results indicate that webRDS could be implemented at a low cost among Internet-using MSM in Vietnam. WebRDS may be a promising method for sampling of Internet-using MSM and other hidden groups. 相似文献90.
Cuong Q Nguyen Janet G Cornelius Lauren Cooper Jonathan Neff Joann Tao Byung Ha Lee Ammon B Peck 《Arthritis research & therapy》2008,10(6):R137