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Imprinting at the KBTBD6 locus involves species-specific m ternal methylation and monoallelic expression in livestock animals
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作者 Jinsoo Ahn In-Sul Hwang +2 位作者 Mi-Ryung Park Seongsoo Hwang Kichoon Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期127-145,共19页
Background The primary differentially methylated regions(DMRs) which are maternally hypermethylated serve as imprinting control regions(ICRs) that drive monoallelic gene expression, and these ICRs have been investigat... Background The primary differentially methylated regions(DMRs) which are maternally hypermethylated serve as imprinting control regions(ICRs) that drive monoallelic gene expression, and these ICRs have been investigated due to their implications in mammalian development. Although a subset of genes has been identified as imprinted, in-depth comparative approach needs to be developed for identification of species-specific imprinted genes. Here, we examined DNA methylation status and allelic expression at the KBTBD6 locus across species and tissues and explored potential mechanisms of imprinting.Results Using whole-genome bisulfite sequencing and RNA-sequencing on parthenogenetic and normal porcine embryos, we identified a maternally hypermethylated DMR between the embryos at the KBTBD6 promoter Cp G island and paternal monoallelic expression of KBTBD6. Also, in analyzed domesticated mammals but not in humans, non-human primates and mice, the KBTBD6 promoter Cp G islands were methylated in oocytes and/or allelically methyl-ated in tissues, and monoallelic KBTBD6 expression was observed, indicating livestock-specific imprinting. Further analysis revealed that these Cp G islands were embedded within transcripts in porcine and bovine oocytes which coexisted with an active transcription mark and DNA methylation, implying the presence of transcription-dependent imprinting.Conclusions In this study, our comparative approach revealed an imprinted expression of the KBTBD6 gene in domesticated mammals, but not in humans, non-human primates, and mice which implicates species-specific evolution of genomic imprinting. 展开更多
关键词 Differentially methylated region Domesticated mammal IMPRINTING KBTBD6 PARTHENOGENETIC
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Advances in DNA methylation and its role in cytoplasmic male sterility in higher plants
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作者 Atiqur Rahman Hasan Sofiur Rahman +9 位作者 Shakil Uddin Naima Sultana Shirin Akhter Ujjal Kumar Nath Shamsun Nahar Begum Mazadul Islam Afroz Naznin Nurul Amin Sharif Ahmed Akbar Hossain 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期1-19,共19页
The impact of epigenetic modifications like DNA methylation on plant phenotypes has expanded the possibilities for crop development.DNA methylation plays a part in the regulation of both the chromatin structure and ge... The impact of epigenetic modifications like DNA methylation on plant phenotypes has expanded the possibilities for crop development.DNA methylation plays a part in the regulation of both the chromatin structure and gene expression,and the enzyme involved,DNA methyltransferase,executes the methylation process within the plant genome.By regulating crucial biological pathways,epigenetic changes actively contribute to the creation of the phenotype.Therefore,epigenome editing may assist in overcoming some of the drawbacks of genome editing,which can have minor off-target consequences and merely facilitate the loss of a gene’s function.These drawbacks include gene knockout,which can have such off-target effects.This review provides examples of several molecular characteristics of DNA methylation,as well as some plant physiological processes that are impacted by these epigenetic changes in the plants.We also discuss how DNA alterations might be used to improve crops and meet the demands of sustainable and environmentally-friendly farming. 展开更多
关键词 DNA methylation EPIGENETICS CMS male sterility chromatin architecture gene expression higher plants
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Gut microbiome therapeutic modulation to alleviate drug-induced hepatic damage in COVID-19 patients 被引量:1
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作者 Khansa Ahsan Munir Ahmad Anwar Nayla Munawar 《World Journal of Gastroenterology》 SCIE CAS 2023年第11期1708-1720,共13页
Coronavirus disease 2019(COVID-19)infection caused by the severe acute respiratory syndrome coronavirus 2 virus,its symptoms,treatment,and post-COVID-19 effects have been a major focus of research since 2020.In additi... Coronavirus disease 2019(COVID-19)infection caused by the severe acute respiratory syndrome coronavirus 2 virus,its symptoms,treatment,and post-COVID-19 effects have been a major focus of research since 2020.In addition to respiratory symptoms,different clinical variants of the virus have been associated with dynamic symptoms and multiorgan diseases,including liver abnormalities.The release of cytokines by the activation of innate immune cells during viral infection and the high doses of drugs used for COVID-19 treatment are considered major drivers of liver injury in COVID-19 patients.The degree of hepatic inflammation in patients suffering from chronic liver disease and having COVID-19 could be severe and can be estimated through different liver chemistry abnormality markers.Gut microbiota influences liver chemistry through its metabolites.Gut dysbiosis during COVID-19 treatment can promote liver inflammation.Here,we highlighted the bidirectional association of liver physiology and gut microbiota(gut-liver axis)and its potential to manipulate drug-induced chemical abnormalities in the livers of COVID-19 patients. 展开更多
关键词 COVID-19 Gut-liver axis PROBIOTICS PREBIOTICS Cytokines Gut microbiome
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Epigenetic modification associated with climate regulates betulin biosynthesis in birch
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作者 Jiang Wang Bowei Chen +13 位作者 Shahid Ali Tianxu Zhang Yu Wang He Zhang Lishan Wang Yonglan Zhang Linan Xie Tingbo Jiang Jing Yin Heike W.Sederoff Gaurav Zinta Ronald R.Sederoff Yuhua Li Qingzhu Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期21-35,共15页
The Betula genus contains pentacyclic triterpenoid betulin known for its environmental adaptation and medicinal properties.However,the mechanisms underlying betulin biosynthesis responding to climate change remain unc... The Betula genus contains pentacyclic triterpenoid betulin known for its environmental adaptation and medicinal properties.However,the mechanisms underlying betulin biosynthesis responding to climate change remain unclear.In this study,the role of epigenetic modification(DNA methylation) in betulin biosynthesis was examined and how climatic factors influence it.Whole-genome bisulfite sequencing was performed for greenhouse-grown Chinese white birch(Betula platyphylla Sukaczev) treated with DNA methylation inhibitor zebularine(ZEB) and a natural birch population in Northeast China.ZEB treatment significantly affected the CHH methylation level of transposable elements and betulin content in a hormesis dose-dependent manner.The methylation and expression of bHLH9,a key transcriptional factor controlling betulin biosynthesis,were also consistently affected by ZEB treatment as a hormetic dose-response.In the natural population,there was a positive correlation between promoter methylation of bHLH9 and summer precipitation,while winter temperature was negatively correlated.Thus climate-dependent methylation of bHLH9 regulates the expression of downstream genes involved in betulin biosynthesis.This study highlights the role of environmental signals to induce epigenetic changes that result in betulin production,possibly helping to develop resilient plants to combat ongoing climate change and enhance secondary metabolite production. 展开更多
关键词 EPIGENETICS DNA methylation BETULIN bHLH9 transcription factor HORMESIS Climate change Secondary metabolite
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Synthesis, Characterization and Phytotoxicity Assessment of Intercalated Insect Pheromone, Lignoceric Acid-Zinc Layered Hydroxide Nanohybrid
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作者 Rozita Ahmad Mohd Zobir Hussein +2 位作者 Siti Halimah Sarijo Wan Rasidah Wan Abdul Kadir Taufiq-Yap Yun Hin 《Journal of Environmental Science and Engineering(B)》 2023年第2期75-91,共17页
A long chain insect pheromone for subterranean termites, LC (Lignoceric Acid), was intercalated into the inorganic interlayer, ZLH (Zinc Layered Hydroxide), resulting in the formation of a new nanohybrid, labelled as ... A long chain insect pheromone for subterranean termites, LC (Lignoceric Acid), was intercalated into the inorganic interlayer, ZLH (Zinc Layered Hydroxide), resulting in the formation of a new nanohybrid, labelled as LCN (Lignocerate Nanohybrid). The formation of this inorganic-organic structure nanohybrid was synthesized by the co-precipitation method using ZnO (Zinc Oxide) as the starting material. The PXRD (Powder X-Ray Diffraction) results confirmed the intercalation process although the diffraction patterns of the resultant nanohybrid and the unbound pheromone were fairly similar but both have different basal spacings values. The FTIR (Fourier Transform Infrared) profiles and the chemical composition test supported the intercalation process with the percentage loading of LC into ZLH calculated to be 85%. The thermal stability of the free anion, LC was enhanced when it was transformed into LCN, increasing from 257 °C to 352 °C. The release of LC from the nanohybrid behaved in a sustained manner, governed by the pseudo-second order kinetic model with higher release of LC in sodium carbonate solution than the pH aqueous media. The synthesized nanohybrid was found to be safe for plant germination when the two seed types were successfully germinated in all the tested nanohybrid concentrations. However, the percentage seed germination and the radical seed length from the nanohybrid showed lower values compared to its counterpart anion, LC. 展开更多
关键词 Insect pheromone ZLH ZnO controlled release TERMITE
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水稻(Oryza sativa L.)α-淀粉酶基因的进化及组织表达模式 被引量:10
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作者 廖登群 张洪亮 +1 位作者 李自超 John BENNETT 《作物学报》 CAS CSCD 北大核心 2010年第1期17-27,共11页
α-淀粉酶在植物特别是谷类萌发种子淀粉降解中具有重要作用。水稻α-淀粉酶基因的结构、进化和表达研究已有报道,但多集中于OsAmy1和OsAmy3这两个亚族内基因间以及发芽种子中。不同亚族间的基因结构、进化及更多组织和时期的表达特点... α-淀粉酶在植物特别是谷类萌发种子淀粉降解中具有重要作用。水稻α-淀粉酶基因的结构、进化和表达研究已有报道,但多集中于OsAmy1和OsAmy3这两个亚族内基因间以及发芽种子中。不同亚族间的基因结构、进化及更多组织和时期的表达特点尚缺乏细致研究。本研究通过TblastN同源性比对及保守结构域分析揭示水稻基因组含有11个α-淀粉酶基因。生物信息学分析、系统进化树构建及半定量RT-PCR分析表明,该家族基因在结构上发生了明显的分化,具有清晰的进化层次,OsAmy5A和OsAmy4A是家族中较原始状态的基因;在表达和功能上也发生了明显分化,进化水平较高的基因发生了明显的时空表达特异性分化。OsAmy1A、OsAmy3A及OsAmy3D和OsAmy3E分别在保证种子植物世代传递、维持种子休眠过程中胚的微弱生命活动及保证种子萌发过程中能量的稳定持续供应上具有重要作用。 展开更多
关键词 水稻 Α-淀粉酶 基因结构 进化 表达
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产酸相中氧化还原电位控制及其对葡萄糖厌氧发酵产物的影响 被引量:5
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作者 周洪波 Cord-Ruwisch +1 位作者 陈坚 任洪强 《中国沼气》 2000年第4期20-23,共4页
以两种厌氧污泥和一种绵羊胃液 (rumen)的混合物为接种物 ,对葡萄糖进行厌氧发酵。通过调节通气和搅拌控制发酵系统的氧化还原电位 ,考察了恒化器中氧化还原电位对葡萄糖厌氧发酵产物生成的影响。结果表明 ,氧化还原电位对发酵产物有强... 以两种厌氧污泥和一种绵羊胃液 (rumen)的混合物为接种物 ,对葡萄糖进行厌氧发酵。通过调节通气和搅拌控制发酵系统的氧化还原电位 ,考察了恒化器中氧化还原电位对葡萄糖厌氧发酵产物生成的影响。结果表明 ,氧化还原电位对发酵产物有强烈影响。在pH 6和水力停留时间 5h及 10h时 ,在Eh - 550~ - 30 0mV ,乙酸和乳酸是主要产物 ,丁酸浓度随Eh的升高而降低 ,而丙酸和甲酸浓度随Eh升高而增加。当Eh >- 2 0 0mV ,除乙醇外的所有产物浓度都急剧下降 ,而此时的电子回收率极低 ,约为 4 0 %。在Eh >- 10 0mV ,pH <3 5的条件下 ,酵母是主要微生物 ,而乙醇是主要产物 ;高的氧化还原电位有利于酵母的生长 ,而低的氧化还原电位有利于乙醇的形成。 展开更多
关键词 产酸相 氧化还原电位 葡萄糖 厌氧发酵 发酵产物
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响应面法优化姬松茸液体发酵培养基中红糖和酵母膏浓度 被引量:11
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作者 范雷法 潘慧娟 +1 位作者 Soccol CR Pandey A 《食用菌学报》 2005年第3期27-31,共5页
运用响应面分析法优化姬松茸液体发酵培养基中红糖和酵母膏浓度。结果表明,红糖浓度为20.24g/L、酵母膏浓度为2.055g/L时,菌丝体生物量最高,达2.279g/L;红糖浓度为20.8g/L、酵母膏浓度为2.23g/L时,胞外多糖产量最高,达0.749g/L。
关键词 响应面分析法 姬松茸 红糖 酵母膏
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姬松茸胞外多糖抗肿瘤活性研究 被引量:7
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作者 范雷法 潘慧娟 +1 位作者 Soccol CR Pamdey A 《食用菌学报》 2004年第2期45-47,共3页
通过深层发酵培养姬松茸菌丝体,滤取菌丝体后获得菌丝体培养液,经沉淀离心收集其胞外粗多糖,再用蒸馏水溶解,取可溶性部分。对接种S 180的小白鼠24h后腹腔注射给药,连续10d,剂量为10mg kg·d。5周后剥取瘤块,与对照组比较瘤重。结... 通过深层发酵培养姬松茸菌丝体,滤取菌丝体后获得菌丝体培养液,经沉淀离心收集其胞外粗多糖,再用蒸馏水溶解,取可溶性部分。对接种S 180的小白鼠24h后腹腔注射给药,连续10d,剂量为10mg kg·d。5周后剥取瘤块,与对照组比较瘤重。结果发现,姬松茸深层发酵生产的胞外多糖对小鼠接种的腹水瘤S 180有较强的抗性,肿瘤抑制率达到44.53%,完全抑制率达到50%。 展开更多
关键词 姬松茸 胞外多糖 抗肿瘤活性 菌丝体培养液
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姬松茸深层发酵生产胞外多糖的碳氮源研究
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作者 潘慧娟 吴应美 +2 位作者 范雷法 Soccol CR Pandey A 《中国食用菌》 2006年第2期44-46,共3页
研究表明摇床振荡培养有利于姬松茸菌丝体生长,而静止培养有利于其胞外多糖的合成。以胞外多糖为目标的研究中,为排除定粉类多糖(碳源)的干扰,红糖是比较理想的碳源,红糖的浓度以20g/L以内,酵母膏是较好的氮源。
关键词 姬松茸 胞外多糖 发酵 碳氮源
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In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus 被引量:5
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作者 Sathish Kumar SR Kokati Venkata Bhaskara Rao 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第10期787-792,共6页
Objective:To investigate the antibacterial aclivily of marine actinobacteria against multidrug resistance Staphylococcus aureus(MDRSA).Methods:Fifty one actinobacterial strains were isolated from salt pans soil,costal... Objective:To investigate the antibacterial aclivily of marine actinobacteria against multidrug resistance Staphylococcus aureus(MDRSA).Methods:Fifty one actinobacterial strains were isolated from salt pans soil,costal area in Kothapattanam,Ongole,Andhra Pradesh.Primary screening was done using cross-streak method against MDRSA.The bioaclive compounds are extracted from efficient actinobacteria using solvent extraction.The antimicrobial activity of crude and solvent extracts was perfomied using Kirby-Bauer method.MIC for ethyl acetate extract was determined by modified agar well diffusion method.The potent actinobacteria are identified using Nonomura key,Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology.Results:Among the fifty one isolates screened for antibacterial activity,SRB25were found efficient against MDRSA.The ethyl acetate extracts showed high inhibition against test organism.MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000μg/mL.The isolaled actinobacteria are identified as Streptomyces sp with the help of Nonomura key.Conclusions:The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms. 展开更多
关键词 MARINE ACTINOBACTERIA Salt pan Multi drug resistance STAPHYLOCOCCUS aureus Cross STREAK METHOD Kirby-Bauer METHOD MIC Nonomura key
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Matrix metalloproteinases and gastrointestinal cancers: Impacts of dietary antioxidants 被引量:10
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作者 Sugreev Verma Kousik Kesh +2 位作者 Nilanjan Ganguly Sayantan Jana Snehasikta Swarnakar 《World Journal of Biological Chemistry》 CAS 2014年第3期355-376,共22页
The process of carcinogenesis is tightly regulated by antioxidant enzymes and matrix degrading enzymes, namely, matrix metalloproteinases(MMPs). Degradation of extracellular matrix(ECM) proteins like collagen, proteog... The process of carcinogenesis is tightly regulated by antioxidant enzymes and matrix degrading enzymes, namely, matrix metalloproteinases(MMPs). Degradation of extracellular matrix(ECM) proteins like collagen, proteoglycan, laminin, elastin and fibronectin is considered to be the prerequisite for tumor invasion and metastasis. MMPs can degrade essentially all of the ECM components and, most MMPs also substantially contribute to angiogenesis, differentiation, proliferation and apoptosis. Hence, MMPs are important regulators of tumor growth both at the primary site and in distant metastases; thus the enzymes are considered as important targets for cancer therapy. The implications of MMPs in cancers are no longer mysterious; however, the mechanism of action is yet to be explained. Herein, our major interest is to clarify how MMPs are tied up with gastrointestinal cancers. Gastrointestinal cancer is a variety of cancer types, including the cancers of gastrointestinal tract and organs, i.e., esophagus, stomach, biliary system, pancreas, small intestine, large intestine, rectum and anus. The activity of MMPs is regulated by its endogenous inhibitor tissue inhibitor of metallopro-teinase(TIMP) which bind MMPs with a 1:1 stoichiometry. In addition, RECK(reversion including cysteinerich protein with kazal motifs) is a membrane bound glycoprotein that inhibits MMP-2,-9 and-14. Moreover, α2-macroglobulin mediates the uptake of several MMPs thereby inhibit their activity. Cancerous conditions increase intrinsic reactive oxygen species(ROS) through mitochondrial dysfunction leading to altered protease/anti-protease balance. ROS, an index of oxidative stress is also involved in tumorigenesis by activation of different MAP kinase pathways including MMP induction. Oxidative stress is involved in cancer by changing the activity and expression of regulatory proteins especially MMPs. Epidemiological studies have shown that high intake of fruits that rich in antioxidants is associated with a lower cancer incidence. Evidence indicates that some antioxidants inhibit the growth of malignant cells by inducing apoptosis and inhibiting the activity of MMPs. This review is discussed in six subchapters, as follows. 展开更多
关键词 GASTROINTESTINAL cancer MATRIX METALLOPROTEINASE Tissue inhibitor of MATRIX METALLOPROTEINASES Reactive oxygen species ANTIOXIDANTS
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Doxycycline blocks gastric ulcer by regulating matrix metalloproteinase-2 activity and oxidative stress 被引量:5
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作者 Laishram Pradeepkumar Singh Amartya Mishra +1 位作者 Debjit Saha Snehasikta Swarnakar 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第28期3310-3321,共12页
AIM: To examine the effect of doxycycline on the activity of matrix metalloproteinases (MMPs) and oxidative stress in gastric tissues of rats following gastric injury.METHODS: Gastric ulcers were generated in rats by ... AIM: To examine the effect of doxycycline on the activity of matrix metalloproteinases (MMPs) and oxidative stress in gastric tissues of rats following gastric injury.METHODS: Gastric ulcers were generated in rats by administration of 70% ethanol,and activity of doxycycline was tested by administration 30 min prior to ethanol.Similarly,the effect of doxycycline was tested in an indomethacin-induced gastric ulcer model.The activities and expression of MMPs were examined by zymography and Western blot analysis.RESULTS: Gastric injury in rats as judged by elevated ulcer indices following exposure to ulcerogen,either indomethacin or ethanol,was reversed significantly by doxycycline.Indomethacin-induced ulcerated gastric tissues exhibited about 12-fold higher proMMP-9 activity and about 5-fold higher proMMP-3 activity as compared to control tissues.Similarly,ethanol induced about 22-fold and about 6-fold higher proMMP-9 and proMMP-3 activities,respectively,in rat gastric tissues.Both proMMP-9 and MMP-3 activities were markedly decreased by doxycycline in ulcerogen treated rat gastric tissues.In contrast,the reduced MMP-2 activity in ulcerated tissues was increased by doxycycline during ulcer prevention.On the other hand,doxycycline inhibited significantly proMMP-9,-2 and -3 activities in vitro.In addition,doxycycline reduced oxidative load in gastric tissues and scavenged H2O2 in vitro.Our results suggest a novel regulatory role of doxycycline on MMP-2 activity in addition to inhibitory action on MMP-9 and MMP-3 during prevention of gastric ulcers.CONCLUSION: This is the first demonstration of dual action of doxycycline,that is,regulation of MMP activity and reduction of oxidative stress in arresting gastric injury. 展开更多
关键词 基质金属蛋白酶 强力霉素 氧化应激 胃溃疡 活性相 MMPS 吲哚美辛 BLOT分析
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Use of Major Quantitative Trait Loci to Improve Grain Yield of Rice 被引量:8
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作者 GUO Long-biao YE Guo-you 《Rice science》 SCIE 2014年第2期65-82,共18页
Further improvement of rice productivity remains a challenge. Breeding is perceived as an important option to increase rice yield. However, the genetic progress of grain yield in most rice breeding programs was slow i... Further improvement of rice productivity remains a challenge. Breeding is perceived as an important option to increase rice yield. However, the genetic progress of grain yield in most rice breeding programs was slow in the last decades. Although great progress in rice genomics and molecular biology has been achieved, the effect of such technological innovations on rice breeding is far small. Markerassisted selection(MAS) for a few target quantitative trait loci(QTLs) has significant effects in improving qualitative traits, such as disease resistance. The success of MAS has therefore motivated breeders to identify and use major QTLs for yield and yield component traits. In this review, we summarized the recent methods in QTL identification, including novel statistical methods for linkage and association mapping, special population types, and whole-genome sequencing. We reviewed the successful application of marker-assisted gene introgression and gene pyramiding to improve grain yield and discussed the design of efficient MAS schemes to further increase the success rate of breeding programs. The use of well-characterized major QTLs through introgression and gene pyramiding is proven effective in improving grain yield, particularly yield under abiotic stress. Major QTLs that are stable across genetic background and growing environments are often found in less adapted germplasms, such as landraces and wild relatives. Advanced backcross QTL analysis and introgression lines, which integrate QTL discovery and utilization, are important methods for exploiting major QTLs contained in such germplasms. Nextgeneration sequencing substantially increases mapping resolution and accelerates the identification of casual genes underlying major QTLs. Practical guidelines derived from theoretical and empirical studies are given to guide the design of efficient marker-assisted gene introgression and pyramiding schemes. 展开更多
关键词 数量性状基因座 水稻产量 分子标记辅助选择 QTL分析 全基因组测序 育种计划 粮食产量 产量构成性状
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Anthrax: A disease of biowarfare and public health importance 被引量:6
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作者 Ajay Kumar Goel 《World Journal of Clinical Cases》 SCIE 2015年第1期20-33,共14页
Bioterrorism has received a lot of attention in the first decade of this century. Biological agents are considered attractive weapons for bioterrorism as these are easy to obtain, comparatively inexpensive to produce ... Bioterrorism has received a lot of attention in the first decade of this century. Biological agents are considered attractive weapons for bioterrorism as these are easy to obtain, comparatively inexpensive to produce and exhibit widespread fear and panic than the actual potential of physical damage. Bacillus anthracis(B. anthracis), the etiologic agent of anthrax is a Gram positive, spore forming, non-motile bacterium. This is supposed to be one of the most potent BW agents because its spores are extremely resistant to natural conditions and can survive for several decades in the environment. B.anthracis spores enter the body through skin lesion(cutaneous anthrax), lungs(pulmonary anthrax), or gastrointestinal route(gastrointestinal anthrax) and germinate, giving rise to the vegetative form. Anthrax is a concern of public health also in many countries where agriculture is the main source of income including India. Anthrax has been associated with human history for a very long time and regained its popularity after Sept 2001 incidence in United States. The present review article describes the history, biology, life cycle, pathogenicity, virulence, epidemiology and potential of B. anthracis as biological weapon. 展开更多
关键词 ANTHRAX BACILLUS ANTHRACIS Biological warfare EPIDEMIOLOGY Infection PUBLIC health
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Gamma Irradiation of Embryogenic Callus Cultures and In vitro Selection for Salt Tolerance in Sugarcane (Saccharum officinarum L.) 被引量:6
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作者 Vikas Y Patade P Suprasanna V A Bapat 《Agricultural Sciences in China》 CAS CSCD 2008年第9期1147-1152,共6页
Radiation induced mutagenesis followed by in vitro selection was employed for salt tolerance in popular Indian sugarcane (Saccharum officinarum L.) cv. CoC-671. Embryogenic calli were gamma irradiated and exposed to d... Radiation induced mutagenesis followed by in vitro selection was employed for salt tolerance in popular Indian sugarcane (Saccharum officinarum L.) cv. CoC-671. Embryogenic calli were gamma irradiated and exposed to different levels of NaCl (42.8,85.6,128.3,171.1,213.9,256.7,299.5,or 342.2 mM). The relative growth rate (RGR) decreased progressively with increasing salt stress and was the least with a salt stress of 256.7 mM (0.25 ± 0.009),almost 10 fold lesser than the control. The RGR was significantly lower in 85.6 mM and higher salt stressed calli than the control. The survival percent also decreased,with an increase in NaCl concentration. In case of 10 and 20 Gy irradiated calli,regeneration was observed up to 85.6 mM NaCl selection,medium,whereas,higher treatments (128.3 mM and beyond) exhibited browning initially. However,in the subsequent subcultures,regeneration was obtained in the case of 10 and 20 Gy irradiated calli on 128.3 and 171.1 mM NaCl selections. Higher dose of gamma irradiation (40 Gy) also showed regeneration,but only with 85.6 mM NaCl selection. The unirradiated calli regenerated the highest number of plantlets followed by 10 and 20 Gy irradiated calli on salt selection. A total of 147 plantlets were selected from different salt levels. The salt selected plants are being tested for their field performance. 展开更多
关键词 甘蔗 耐盐性 胚胎发生 组织培养 育种
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Programmed death-1/programmed death-L1 signaling pathway and its blockade in hepatitis C virus immunotherapy 被引量:9
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作者 Mohamed L Salem Ahmed El-Badawy 《World Journal of Hepatology》 CAS 2015年第23期2449-2458,共10页
Chronic hepatitis C virus(HCV) infection is a public health issue that often progresses to life-threatening complications, including liver cirrhosis, fibrosis, and hepatocellular carcinoma. Impaired immune responses t... Chronic hepatitis C virus(HCV) infection is a public health issue that often progresses to life-threatening complications, including liver cirrhosis, fibrosis, and hepatocellular carcinoma. Impaired immune responses to HCV are key features of chronic HCV infection. Therefore, intervention strategies usually involve enhancing the immune responses against HCV. Cytotoxic CD8+ T lymphocytes(CTLs) play a critical role in the control of HCV infection. However, their cytolytic function can be impaired by the expression of co-inhibitory molecules. Programmed death-1(PD-1) receptor and its ligand PD-L1 function in a T cell co-inhibitory pathway, which either blocks the function of CTLs or the differentiation of CD8+ T cells. During chronic HCV infection, the immune inhibitory receptor PD-1 is upregulated on dysfunctional HCV-specific CD8+ T cells. As such, blockade of the PD-1/PD-L1 pathway in these CD8+ T cells might restore their functional capabilities. Indeed, clinical trials using therapies to block this pathway have shown promise in the fostering of anti-HCV immunity. Understanding how chronic HCV infection induces upregulation of PD-1 on HCV specific T cells and how the PD-1/PD-L1 interaction develops HCV specific T cell dysfunction will accelerate the development of an efficacious prophylactic and therapeutic vaccination against chronic HCV infections, which will significantly improve HCV treatments and patient survival. In this review, we discuss the relationship between PD-1 expression and clinical responses and the potential use of PD-1 blockade for anti-HCV therapy. 展开更多
关键词 HEPATITIS C virus Programmed death-1 HEPATITIS C v
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Molecular Improvement of Grain Weight and Yield in Rice by Using GW6 Gene 被引量:6
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作者 LI Yuan-yuan TAO Hong-jian +9 位作者 ZHAO Xiang-qian XU Jie LI Geng-mi HU Shi-kai DONG Guo-jun SHI Zheng-yuan WU Li-wen HU Jiang YE Guo-you GUO Long-biao 《Rice science》 SCIE 2014年第3期127-132,共6页
Molecular design breeding is one of straightforward approaches to break yield barriers in rice. In this study, GW6 gene for grain length and width from Baodali was transferred into an indica recurrent parent 9311 and ... Molecular design breeding is one of straightforward approaches to break yield barriers in rice. In this study, GW6 gene for grain length and width from Baodali was transferred into an indica recurrent parent 9311 and a japonica variety Zhonghua 11(ZH11) using marker-assisted backcross(MAB). One and three introgression lines were selected for phenotypic analysis from 9311 and ZH11 genetic backgrounds, respectively. SSL-1, an improved 9311 near isogenic line with GW6 performed 11%, 19% and 6.7% higher of grain length, 1000-grain weight and single plant yield, respectively, as compared with 9311. All the three improved ZH11-GW6 lines, R1, R2 and R3, had more than 30% increase in grain weight and about 7% higher in grain yield. Seed plumpness of R1, R2 and R3 was improved synchronously because the three ZH11-GW6 lines contained GIF1(Grain Incomplete Filling 1), a dominant grain filling gene. Thus, GW6 has high potential in increasing the yield of inbred lines through MAB, making it an important genetic resource in super hybrid rice breeding. This study provides insights in the utilization of GW6 for large grain and high yield rice breeding via molecular design breeding. 展开更多
关键词 近等基因系 水稻产量 千粒重 分子改良 分子设计育种 人与生物圈计划 分子标记辅助 谷物产量
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Genotoxic Effects of PAH Containing Sludge Extracts in Chinese Hamster Ovary Cell Cultures 被引量:4
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作者 K.KRISHNAMURTHI FONTDEVI T.CHAKRABARTI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第1期68-82,共15页
Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now question... Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society[1]. Methods Keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS. 展开更多
关键词 遗传毒性 DNA损伤 染色体变异 多环芳香烃 P53基因 GC-MS
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Protective Effect of Distillate and Redistillate of Cow’s Urine in Human Polymorphonuclear Leukocytes Challenged With Established Genotoxic Chemicals 被引量:3
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作者 K.KRISHNAMURTHI DIPANWITA DUTTA +1 位作者 S.D.SIVANESAN T. CHAKRABARTI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第3期247-256,共10页
Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cau... Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow’urine. Methods In the present investigation, the antigenotoxic/ antioxidant properties of cow’ urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1ol/L) and hydrogen peroxide (150 mol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow’ urine was chosen from the dose response study carried out earlier. Results Both actinomycin-D and H2O2 caused statistically significant DNA unwinding of 80% & 75% respectively (P<0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow urine distillate (1, 50 & 100 ) in simultaneous treatment with genotoxic chemicals. Conclusion The redistillate of cowurine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects. 展开更多
关键词 保护作用 复蒸馏物 蒸馏液 母牛 尿液检查 分叶核白细胞 激发作用 氧化反应 氨抗氧化剂 人类多形核白细胞 PMNL's DNA损害 荧光分析DNA退绕 FADU 气体色谱质量分光计 GC-MS 生殖毒性 易失脂肪
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