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111.
Trinh Xuan Hoat Ngo Gia Bon Mai Van Quan Vu Duy Hien Nguyen Duc Thanh Matthew Dickinson 《Phytoparasitica》2012,40(4):351-359
Sugarcane is an important cash crop in Vietnam and has been widely promoted at national and provincial level. In 2006, a new disease was discovered in sugarcane in the Nghean Tate&Lyle Sugar Mill in Nghean Province in north-central Vietnam. The key symptoms were the formation of green grassy shoots around the base of mature stools. We applied nested polymerase chain reaction (PCR) using P1/P7 and R16F2n/R16R2 for detection and characterization of phytoplasma from the symptomatic tissues. PCR products of the expected size (approx. 1200?bp) were obtained from the 16S rDNA of the phytoplasma. The restriction fragment length polymorphism profiles indicated that all samples were infected by the same phytoplasma. Phylogenetic analysis confirmed that the SCGS phytoplasma from Vietnam belong to the 16SrXI group, formerly Rice Yellow Dwarf group. 相似文献
112.
农业耕地土壤中114株农药降解菌的分离与筛选 总被引:3,自引:0,他引:3
根据农田使用农药史选择灭蝇胺、氯氰菊酯、异丙威进行农药富集培养和平板划线分离,在28种长期受农药污染的不同作物耕地土壤中分离到114株农药降解菌,并用高效液相色谱法测试对吡虫啉(100μg/ml)的降解率,72 h后进行检测。结果 114株降解菌中用吡虫啉筛选到10株降解率达到25%以上的细菌,降解率为10%~25%之间的细菌为78株,降解率小于10%的细菌为26株。对农药降解效果较好的降解菌主要分布在长期大量使用农药的蔬菜作物(大姜、大葱、芦笋等)耕地土壤,而施药相对较少的果园和棉花田中降解菌的数目和降解能力偏低。 相似文献
113.
Liang ZS Nguyen T Mattila HR Rodriguez-Zas SL Seeley TD Robinson GE 《Science (New York, N.Y.)》2012,335(6073):1225-1228
Little is known about the molecular basis of differences in behavior among individuals. Here we report consistent novelty-seeking behavior, across different contexts, among honey bees in their tendency to scout for food sources and nest sites, and we reveal some of the molecular underpinnings of this behavior relative to foragers that do not scout. Food scouts showed extensive differences in brain gene expression relative to other foragers, including differences related to catecholamine, glutamate, and γ-aminobutyric acid signaling. Octopamine and glutamate treatments increased the likelihood of scouting, whereas dopamine antagonist treatment decreased it. These findings demonstrate intriguing similarities in human and insect novelty seeking and suggest that this trait, which presumably evolved independently in these two lineages, may be subserved by conserved molecular components. 相似文献
114.
Le Dinh Kha Chris E. Harwood Nguyen Duc Kien Brian S. Baltunis Nguyen Dinh Hai Ha Huy Thinh 《New Forests》2012,43(1):13-29
Field trials testing a total of 27 clones of the interspecific hybrid Acacia mangium × A.
auriculiformis and seedling controls of the parental species were established at Ba Vi and Yen Thanh in the north of Vietnam and Long Thanh
in the south. At both Ba Vi and Yen Thanh there were significant (P < 0.001) differences in height and diameter at breast height (DBH) among 22 tested clones at 4 years. At Long Thanh, twelve
hybrid clones did not differ significantly in DBH at age 3 years, but did (P < 0.001) at age 5 years. At the two northern sites the acacia hybrid clones had significantly greater DBH than control seedlots
of the parental species. At Long Thanh, DBH of the hybrid clones and A. mangium was similar, with a genetically improved seedlot of A. mangium displaying the best DBH. Mean wood basic density at breast height of the acacia hybrid clones was 539 kg m−3 at Yen Thanh at age 8 years, and 473 kg m−3 at Long Thanh at age 5 years; density for A. mangium at Long Thanh was only slightly lower than the hybrid clones at 461 kg m−3. Linear regressions of Pilodyn penetration (PP) at breast height on wood basic density explained 60% of the variance in density
of treatments (clones and control seedlots) at Yen Thanh and 36% at Long Thanh. There were significant differences between
hybrid clones in PP at all three trial sites. Clonal DBH performance was not strongly correlated across the three trial sites;
Pearson correlations of clone mean DBH between pairs of sites ranged from −0.47 to 0.20. Clonal rankings for PP were more
stable, with Pearson correlations between pairs of sites ranging from r = 0.71 to 0.78. 相似文献
115.
116.
Tae-Hyun Kim Young-Woo Park Jae-Sang Ahn Jeong-Taek Ahn Se-Eun Kim Man-Bok Jeong Min-Su Seo Kyung-Sun Kang Kang-Moon Seo 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):61-67
This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits. 相似文献
117.
Kyung-Mee Park Sang-Ho Cha Cheol Ahn Heung-Myong Woo 《Veterinary research communications》2013,37(4):293-301
Induced pluripotent stem cells (iPSCs) are thought to be highly beneficial in the field of regenerative medicine and are believed to overcome immunogenic barriers to cell transplantation. However, issues remain regarding their safety and efficiency for medical use. Furthermore, some recent reports have suggested that iPSCs could be targeted by the autologous immune system. To promote practical applications of iPSCs, in depth research using appropriate animal models is needed and porcine species appear to provide an ideal model. Recent studies have focused on the generation of porcine iPSC cells, but no investigations of their immunological properties have been conducted to date. In the present study, we generated putative iPSCs from porcine somatic cells and measured major histocompatibility complex (MHC) expression on the iPSCs and their derivatives. Compact colonies that expressed pluripotent markers appeared 11 days after viral infection. Embryonic bodies (EB) were produced and differentiated into three germ layers in vitro. Karyotyping and swine leukocyte antigen (SLA) typing showed that the iPSCs were identical to parental somatic cells. Porcine iPSCs expressed only low levels of MHC class I and moderately increased levels on their differentiated derivatives, whereas MHC class II was rarely expressed. In the presence of interferon-gamma (IFN-γ), the expression of MHC class I was elevated on differentiated iPSCs, and gradually decreased after withdrawal of the cytokine. Our data suggest that porcine iPSCs could be useful for preclinical studies of the efficiency and viability of iPSCs, and for devising strategies to rescue transplanted cells from the autologous immune system. 相似文献
118.
Nguyen Phuong Thao Nguyen Xuan Cuong Bui Thi Thuy Luyen Tran Hong Quang Tran Thi Hong Hanh Sohyun Kim Young-Sang Koh Nguyen Hoai Nam Phan Van Kiem Chau Van Minh Young Ho Kim 《Marine drugs》2013,11(8):2917-2926
Inflammation is important in biomedical research, because it plays a key role in inflammatory diseases including rheumatoid arthritis and other forms of arthritis, diabetes, heart disease, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, and even cancer. In the present study, we describe the inhibitory effect of crude extracts and steroids isolated from the starfish Astropecten polyacanthus on pro-inflammatory cytokine (Interleukin-12 (IL-12) p40, interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α)) production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs). Among those tested, compounds 5 and 7 showed potent inhibitory effects on the production of all three pro-inflammatory cytokines with IC50 values ranging from 1.82 ± 0.11 to 7.00 ± 0.16 μM. Potent inhibitory activities were also observed for compound 1 on the production of IL-12 p40 and IL-6 with values of 3.96 ± 0.12 and 4.07 ± 0.13 μM, respectively, and for compounds 3 and 4 on the production of IL-12 p40 with values of 6.55 ± 0.18 and 5.06 ± 0.16 μM, respectively. Moreover, compounds 2 (IC50 = 34.86 ± 0.31 μM) and 6 (IC50 = 79.05 ± 2.05 μM) exhibited moderate inhibitory effects on the production of IL-12 p40, whereas compounds 3 (IC50 = 22.80 ± 0.21 μM) and 4 (IC50 = 16.73 ± 0.25 μM) moderately inhibited the production of TNF-α and IL-6, respectively. 相似文献
119.
Penicillinolide A: A New Anti-Inflammatory Metabolite from the Marine Fungus Penicillium sp. SF-5292
Dong-Sung Lee Wonmin Ko Tran Hong Quang Kyoung-Su Kim Jae Hak Sohn Jae-Hyuk Jang Jong Seog Ahn Youn-Chul Kim Hyuncheol Oh 《Marine drugs》2013,11(11):4510-4526
In the course of studies on bioactive metabolites from marine fungi, a new 10-membered lactone, named penicillinolide A (1) was isolated from the organic extract of Penicillium sp. SF-5292 as a potential anti-inflammatory compound. The structure of penicillinolide A (1) was mainly determined by analysis of NMR and MS data and Mosher’s method. Penicillinolide A (1) inhibited the production of NO and PGE2 due to inhibition of the expression of iNOS and COX-2. Penicillinolide A (1) also reduced TNF-α, IL-1β and IL-6 production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of IκB-α, NF-κB nuclear translocation, and NF-κB DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), a competitive inhibitor of HO activity, it was verified that the inhibitory effects of compound 1 on the production of pro-inflammatory mediators and NF-κB DNA binding activity were partially associated with HO-1 expression through Nrf2 nuclear translocation. 相似文献
120.
Tho Nguyen Thi Thuy Hieu Tran 《Communications in Soil Science and Plant Analysis》2019,50(9):1170-1177
This paper examined the contribution of various soil components to pH buffering capacity (pHBC) of haplic Acrisols in an upland area of Southeastern Vietnam. Sampling was conducted in 2016 in Tan Bien district, Tay Ninh province at seven sites from the surface to 60-cm depth. Soils were very acidic (pHH2O 4.53 ± 0.05). The pHBC were very low, 0.46 ± 0.04 and 0.44 ± 0.05 cmol H+ kg?1 pH?1, respectively, for original samples and those from which soil organic carbon (SOC, 0.52 ± 0.09%) were removed. The contribution of Al3+ to pHBC was remarkable while that of SOC was of little significance. The contribution of clay minerals to pHBC was unclear due to the low (9.37 ± 0.76%) and kaolinite-dominated clay content. The current soil conditions indicated a potential for further soil acidification. Liming would be one of the measures to remediate soil acidity in the research area. 相似文献