AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric...AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric biopsies from 206 Colombian patients with dyspeptic symptoms from a high-risk area for gastric cancer were included as study material.Antimicrobial susceptibility was determined by the agar dilution method.Resistant isolates at baseline and in amoxicillin and clarithromycin serial dilutions were subjected to genotyping(cagA,vacA alleles s and m),Glu-Pro-Ile-Tyr-Ala(EPIYA)polymerase chain reaction and random amplified polymorphic DNA(RAPD).Images of the RAPD amplicons were analyzed by Gel-Pro Analyzer 4.5program.Cluster analyses was done using SPSS 15.0statistical package,where each of the fingerprint bands were denoted as variables.Dendrograms were designed by following Ward’s clustering method and the estimation of distances between each pair of H.pylori isolates was calculated with the squared Euclidean distance.RESULTS:Resistance rates were 4%for amoxicillin and 2.7%for clarithromycin with 2%double resistances.Genotyping evidenced a high prevalence of the genotype cagA-positive/vacA s1m1.The 3’region of cagA gene was successfully amplified in 92.3%(12/13)of the baseline resistant isolates and in 60%(36/60)of the resistant isolates growing in antibiotic dilutions.Upon observing the distribution of the number of EPIYA repetitions in each dilution with respect to baseline isolates,it was found that in 61.5%(8/13)of the baseline isolates,a change in the number of EPIYA repetitions lowered antibiotic pressure.The gain and loss of EPIYA motifs resulted in a diversity of H.pylori subclones after bacterial adjustment to changing conditions product of antibiotic pressure.RAPD PCR evidenced the close clonal relationship between baseline isolates and isolates growing in antibiotic dilutions.CONCLUSION:Antibiotic pressure does not induce loss of the cag pathogenicity island,but it can leadin most cases-to genetic rearrangements within the3’region cagA of the founding bacteria that can affect the level of tyrosine phosphorylation impacting on its cellular effects and lead to divergence of cagA-positive subclones.展开更多
The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luan...The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luanchuan,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in China.展开更多
Curcumin exerts a neuroprotective effect on Alzheimer’s disease;however,it is not known whether microRNAs are involved in this protective effect.This study was conducted using swAPP695-HEK293 cells as an Alzheimer’s...Curcumin exerts a neuroprotective effect on Alzheimer’s disease;however,it is not known whether microRNAs are involved in this protective effect.This study was conducted using swAPP695-HEK293 cells as an Alzheimer’s disease cell model.swAPP695-HEK293 cells were treated with 0,0.5,1,2,5,and 10μM curcumin for 24 hours.The changes in miR-15b-5p,miR-19a-3p,miR-195-5p,miR-101-3p,miR-216b-5p,miR-16-5p and miR-185-5p expression were assessed by real-time quantitative polymerase chain reaction.The mRNA and protein levels of amyloid precursor protein,amyloid-β40 and amyloid-β42 were evaluated by quantitative real-time polymerase chain reaction,western blot assays and enzyme-linked immunosorbent assays.swAPP695-HEK293 cells were transfected with miR-15b-5p mimic,or treated with 1μM curcumin 24 hours before miR-15b-5p inhibitor transfection.The effects of curcumin on amyloid precursor protein,amyloid-β40 and amyloid-β42 levels were evaluated by western blot assays and enzyme-linked immunosorbent assay.Luciferase assays were used to analyze the interaction between miR-15b-5p and the 3′-untranslated region of amyloid precursor protein.The results show that amyloid precursor protein and amyloid-βexpression were enhanced in swAPP695-HEK293 cells compared with HEK293 parental cells.Curcumin suppressed the expression of amyloid precursor protein and amyloid-βand up-regulated the expression of miR-15b-5p in swAPP695-HEK293 cells.In addition,we found a negative association of miR-15b-5p expression with amyloid precursor protein and amyloid-βlevels in the curcumin-treated cells.Luciferase assays revealed that miR-15b-5p impaired the luciferase activity of the plasmid harboring the 3′-untranslated region of amyloid precursor protein.These findings indicate that curcumin down-regulates the expression of amyloid precursor protein and amyloid-βin swAPP695-HEK293 cells,which was partially mediated by miR-15b-5p via targeting of the 3′-untranslated region of amyloid precursor protein.展开更多
AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid cells.METHODS:Gtl2,Rian,and Mirg mRNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined b...AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid cells.METHODS:Gtl2,Rian,and Mirg mRNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined by real-time reverse transcription-polymerase chain reaction.Pyrosequencing and bisulfate sequencing were used to determine the DNA methylation level of the Dlk1-Dio3 locus imprinting control region. RESULTS:The selected hybrid clones had a near-tetraploid karyotype and were highly pluripotent judging from their capacity to generate chimeric embryos and adult chimeras.Our data clearly demonstrate that Gtl2,Rian,and Mirg,which are imprinted genes within the Dlk1-Dio3 locus,are active in all examined ES cell/fibroblast hybrid clones.In spite of interclonal variability,the expression of the imprinted genes is comparable to that of ES cells and fibroblasts.Quantitative analysis of the DNA methylation status of the intergenic differentially methylated region(IG DMR)within the Dlk1-Dio3 locus by pyrosequencing and bisulfite sequencing clearly showed that the DNA methylation status of the imprinted region in the tested hybrid clones was comparable to that of both ES cells and fibroblasts.CONCLUSION:Reprogramming process in a hybrid cell system is achieved without marked alteration of the imprinted Dlk1-Dio3 locus.展开更多
Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over Ea...Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over East Asia using the regional climate model version 4.4 (RegCM4.4)driven by the global models of CSIRO-Mk3-6-0, EC-EARTH, HadGEM2-ES, and MPI-ESM-MR. Under global warming of 1.5℃, 2℃, 3℃,and 4℃, significant decrease of HDD can be found over China without considering population factor, with greater decrease over high elevationand high latitude regions, including the Tibetan Plateau, the northern part of Northeast China, and Northwest China; while population-weightedHDD increased in areas where population will increase in the future, such as Beijing, Tianjin, parts of southern Hebei, northern Shandong andHenan provinces. Similarly, the CDD projections with and without considering population factor are largely different. Specifically, withoutconsidering population, increase of CDD were observed over most parts of China except the Tibetan Plateau where the CDD remained zerobecause of the cold climate even under global warming; while considering population factor, the future CDD decreases in South China andincreases in North China, the Sichuan Basin, and the southeastern coastal areas, which is directly related to the population changes. The differentfuture changes of HDD and CDD when considering and disregarding the effects of population show that population distribution plays animportant role in energy consumption, which should be considered in future research.展开更多
The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achiev...The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources.展开更多
Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxi...Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxin-associated gene A protein (CagA), encoded by the gene cagA. However, these variants have not been characterized in China, where gastric cancer is common. We investigated the diversity of CagA variants in H. pylori strains isolated from a Chinese population. The 3' variable region of cagA genes from 66 clinical isolates in China were amplified by polymerase chain reaction, sequenced, aligned, and analyzed. All 66 H. pylori strains were CagA-positive, of which 93.9% were East Asian type and the tyrosine phosphorylation motifs (TPMs) were EPIYA-ABD. The remainder was Western type, in which TPMs were EPIYA-ABC. Interestingly, two of sixty-two strains (3.2%) of the East Asian type were mutated into ESIYA-B, whereas all four Western type (100%) strains were mutated into EPIYT-B. Both of the two strains with Western-type CagA obtained from gastric cancer patients contained a distinguished mutation on the first residue following the EPIYA site in the EPIYA-A motif. The predominant CagA type in these H. pylori strains isolated from Chinese patients in China was East Asian, with TPMs EPIYA-ABD, and there existed mutations in both the East Asian and Western type CagA.展开更多
In the present study, we examined the analgesic effect of repeated electroacupuncture at bilateral Zusanfi (ST36) and Yanglingquan (GB34) once a day for 14 consecutive days in a rat model of chronic sciatic nerve ...In the present study, we examined the analgesic effect of repeated electroacupuncture at bilateral Zusanfi (ST36) and Yanglingquan (GB34) once a day for 14 consecutive days in a rat model of chronic sciatic nerve constriction injury-induced neuropathic pain. In addition, concomitant changes in calcium/calmodulin-dependent protein kinase II expression and synaptic ultrastructure of neurons in the hippocampal CA3 region were examined. The thermal pain threshold (paw withdrawal latency) was increased significantly in both groups at 2 weeks after electroacupuncture intervention compared with 2 days of electroacupuncture. In ovariectomized rats with chronic constriction injury, the analgesic effect was significantly reduced. Electroacupuncture for 2 weeks significantly diminished the injury-induced increase in synaptJc cleft width and thinning of the postsynaptJc density, and it significantly suppressed the down-regulation of intracellular calcium/ calmodulin-dependent protein kinase II expression in the hippocampal CA3 region. Repeated electroacupuncture intervention had a cumulative analgesic effect on injury-induced neuropathic pain reactions, and it led to synaptic remodeling of hippocampal neurons and upregulated calcium/calmodulin-dependent protein kJnase II expression in the hippocampal CA3 region.展开更多
At the 3' end of genomic hepatitis C virus(HCV) RNA there is a highly conserved untranslated region,the 3'X-tail,which forms part of the 3'UTR.This region plays key functions in regulation of critical proc...At the 3' end of genomic hepatitis C virus(HCV) RNA there is a highly conserved untranslated region,the 3'X-tail,which forms part of the 3'UTR.This region plays key functions in regulation of critical processes of the viral life cycle.The 3'X region is essential for viral replication and infectivity.It is also responsible for regulation of switching between translation and transcription of the viral RNA.There is some evidence indicating the contribution of the 3'X region to the translation efficiency of the viral polyprotein and to the encapsidation process.Several different secondary structure models of the 3'X region,based on computer predictions and experimental structure probing,have been proposed.It is likely that the 3'X region adopts more than one structural form in infected cells and that a specific equilibrium between the various forms regulates several aspects of the viral life cycle.The most intriguing explanations of the structural heterogeneity problem of the 3'X region came with the discovery of its involvement in long-range RNA-RNA interactions and the potential for homodimer formation.This article summarizes current knowledge on the structure and function of the 3'X region of hepatitis C genomic RNA,reviews previous opinions,presents new hypotheses and summarizes the questions that still remain unanswered.展开更多
Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok dur...Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok during 24 year-evolution(1977-2000) comparing to the DEN3prototype(H87).Methods:The 5'UTRs of these Thai DEN3 and the H87 prototype were amplified by RT-PCR and sequenced.Their multiple sequence alignments were done by Codon Code Aligner v 4.0.4 software and their RNA secondary structures were predicted by MFOLD software.Replication of five Thai DEN3 candidates comparing to the 1187 prototype were done in human(HepG2) and the mosquito(C6/36) cell lines.Results:Among these Thai DEN3,the completely identical sequences of their first 89 nucleotides,their high-order secondary structure of 5'UTRs and three SNPs including the predominant C90 T,and two minor SNPs including A109 G and A112 G were found.The C90 T of Thai DEN3.Bangkok isolates was shown predominantly before 1977.Five Thai DEN3 candidates with the predominant C90 T were shown to replicate in human(HepG2) and the mosquito(C6/36) cell lines better than the H87 prototype.However,their highly conserved sequences as well as SNPs of the 5'UTR did not appear to correlate with their disease severity in human.Conclusions:Our findings highlighted evolutionary relationship of the completely identical 89 nucleotide sequence,the high-order secondary structure and the predominant C90 T of the 5'UTR of these Thai DEN3 during 24 year-evolution further suggesting to be their genetic markers and magic targets for future research on antiviral therapy as well as vaccine approaches of Thai DEN3.展开更多
The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation ...The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation of these genes remain largely unknown.Here,through comparative transcriptome and chromatin immunoprecipitation sequencing(ChIP-seq)analyses of the methyltransferase PoKmt6 in rice blast fungus Pyricularia oryzae(syn.Magnaporthe oryzae),we found that PoKmt6-mediated H3K27me3 deposition was enriched mainly at fast-evolving regions and contributed to the silencing of a subset of secreted proteins(SP)and transposable element(TE)families during the vegetative growth of P.oryzae.Intriguingly,we observed that a group of SP genes,which were depleted of H3K27me3 modification,could also be silenced via the H3K27me3-mediated repression of the nearby TEs.In conclusion,our results indicate that H3K27me3 modification mediated by PoKmt6 regulates the expression of some SP genes in fast-evolving regions through the suppression of nearby TEs.展开更多
Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein codi...Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein coding regions in DNA sequences is based on the period-3 property exhibited by nucleotides in exons. Several approaches based on signal processing tools and numerical representations have been applied to solve this problem, trying to achieve more accurate predictions. This paper presents a new indicator sequence based on amino acid sequence, called as aminoacid indicator sequence, derived from DNA string that uses the existing signal processing based time-domain and frequency domain methods to predict these regions within the billions long DNA sequence of eukaryotic cells which reduces the computational load by one-third. It is known that each triplet of bases, called as codon, instructs the cell machinery to synthesize an amino acid. The codon sequence therefore uniquely identifies an amino acid sequence which defines a protein. Thus the protein coding region is attributed by the codons in amino acid sequence. This property is used for detection of period-3 regions using amino acid sequence. Physico-chemical properties of amino acids are used for numerical representation. Various accuracy measures such as exonic peaks, discriminating factor, sensitivity, specificity, miss rate, wrong rate and approximate correlation are used to demonstrate the efficacy of the proposed predictor. The proposed method is validated on various organisms using the standard data-set HMR195, Burset and Guigo and KEGG. The simulation result shows that the proposed method is an effective approach for protein coding prediction.展开更多
基金Supported by The Administrative Department on Science and Innovation of the Republic of Colombia-COLCIENCIAS,No.RC-1106-408-20549,RC-1106-493-26237its program:Jóvenes Investigadores e Innovadores"Virginia Gutiérrez de Pineda",and by the Universidad del Valle,Cali,Colombia
文摘AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric biopsies from 206 Colombian patients with dyspeptic symptoms from a high-risk area for gastric cancer were included as study material.Antimicrobial susceptibility was determined by the agar dilution method.Resistant isolates at baseline and in amoxicillin and clarithromycin serial dilutions were subjected to genotyping(cagA,vacA alleles s and m),Glu-Pro-Ile-Tyr-Ala(EPIYA)polymerase chain reaction and random amplified polymorphic DNA(RAPD).Images of the RAPD amplicons were analyzed by Gel-Pro Analyzer 4.5program.Cluster analyses was done using SPSS 15.0statistical package,where each of the fingerprint bands were denoted as variables.Dendrograms were designed by following Ward’s clustering method and the estimation of distances between each pair of H.pylori isolates was calculated with the squared Euclidean distance.RESULTS:Resistance rates were 4%for amoxicillin and 2.7%for clarithromycin with 2%double resistances.Genotyping evidenced a high prevalence of the genotype cagA-positive/vacA s1m1.The 3’region of cagA gene was successfully amplified in 92.3%(12/13)of the baseline resistant isolates and in 60%(36/60)of the resistant isolates growing in antibiotic dilutions.Upon observing the distribution of the number of EPIYA repetitions in each dilution with respect to baseline isolates,it was found that in 61.5%(8/13)of the baseline isolates,a change in the number of EPIYA repetitions lowered antibiotic pressure.The gain and loss of EPIYA motifs resulted in a diversity of H.pylori subclones after bacterial adjustment to changing conditions product of antibiotic pressure.RAPD PCR evidenced the close clonal relationship between baseline isolates and isolates growing in antibiotic dilutions.CONCLUSION:Antibiotic pressure does not induce loss of the cag pathogenicity island,but it can leadin most cases-to genetic rearrangements within the3’region cagA of the founding bacteria that can affect the level of tyrosine phosphorylation impacting on its cellular effects and lead to divergence of cagA-positive subclones.
文摘The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luanchuan,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in China.
基金supported by the Science and Technology Planning Project of Guangdong Province of China,No.2016A020226022(to HYL)the Medical and Health Technology Project of Guangzhou of China,No.20161A011068(to HYL)the Guangzhou Science Technology and Innovation Commission of China,No.201704020043(to QCG)
文摘Curcumin exerts a neuroprotective effect on Alzheimer’s disease;however,it is not known whether microRNAs are involved in this protective effect.This study was conducted using swAPP695-HEK293 cells as an Alzheimer’s disease cell model.swAPP695-HEK293 cells were treated with 0,0.5,1,2,5,and 10μM curcumin for 24 hours.The changes in miR-15b-5p,miR-19a-3p,miR-195-5p,miR-101-3p,miR-216b-5p,miR-16-5p and miR-185-5p expression were assessed by real-time quantitative polymerase chain reaction.The mRNA and protein levels of amyloid precursor protein,amyloid-β40 and amyloid-β42 were evaluated by quantitative real-time polymerase chain reaction,western blot assays and enzyme-linked immunosorbent assays.swAPP695-HEK293 cells were transfected with miR-15b-5p mimic,or treated with 1μM curcumin 24 hours before miR-15b-5p inhibitor transfection.The effects of curcumin on amyloid precursor protein,amyloid-β40 and amyloid-β42 levels were evaluated by western blot assays and enzyme-linked immunosorbent assay.Luciferase assays were used to analyze the interaction between miR-15b-5p and the 3′-untranslated region of amyloid precursor protein.The results show that amyloid precursor protein and amyloid-βexpression were enhanced in swAPP695-HEK293 cells compared with HEK293 parental cells.Curcumin suppressed the expression of amyloid precursor protein and amyloid-βand up-regulated the expression of miR-15b-5p in swAPP695-HEK293 cells.In addition,we found a negative association of miR-15b-5p expression with amyloid precursor protein and amyloid-βlevels in the curcumin-treated cells.Luciferase assays revealed that miR-15b-5p impaired the luciferase activity of the plasmid harboring the 3′-untranslated region of amyloid precursor protein.These findings indicate that curcumin down-regulates the expression of amyloid precursor protein and amyloid-βin swAPP695-HEK293 cells,which was partially mediated by miR-15b-5p via targeting of the 3′-untranslated region of amyloid precursor protein.
基金Supported by Grant from the Russian Academy of Sciences,Siberian Branch N48
文摘AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid cells.METHODS:Gtl2,Rian,and Mirg mRNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined by real-time reverse transcription-polymerase chain reaction.Pyrosequencing and bisulfate sequencing were used to determine the DNA methylation level of the Dlk1-Dio3 locus imprinting control region. RESULTS:The selected hybrid clones had a near-tetraploid karyotype and were highly pluripotent judging from their capacity to generate chimeric embryos and adult chimeras.Our data clearly demonstrate that Gtl2,Rian,and Mirg,which are imprinted genes within the Dlk1-Dio3 locus,are active in all examined ES cell/fibroblast hybrid clones.In spite of interclonal variability,the expression of the imprinted genes is comparable to that of ES cells and fibroblasts.Quantitative analysis of the DNA methylation status of the intergenic differentially methylated region(IG DMR)within the Dlk1-Dio3 locus by pyrosequencing and bisulfite sequencing clearly showed that the DNA methylation status of the imprinted region in the tested hybrid clones was comparable to that of both ES cells and fibroblasts.CONCLUSION:Reprogramming process in a hybrid cell system is achieved without marked alteration of the imprinted Dlk1-Dio3 locus.
文摘Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over East Asia using the regional climate model version 4.4 (RegCM4.4)driven by the global models of CSIRO-Mk3-6-0, EC-EARTH, HadGEM2-ES, and MPI-ESM-MR. Under global warming of 1.5℃, 2℃, 3℃,and 4℃, significant decrease of HDD can be found over China without considering population factor, with greater decrease over high elevationand high latitude regions, including the Tibetan Plateau, the northern part of Northeast China, and Northwest China; while population-weightedHDD increased in areas where population will increase in the future, such as Beijing, Tianjin, parts of southern Hebei, northern Shandong andHenan provinces. Similarly, the CDD projections with and without considering population factor are largely different. Specifically, withoutconsidering population, increase of CDD were observed over most parts of China except the Tibetan Plateau where the CDD remained zerobecause of the cold climate even under global warming; while considering population factor, the future CDD decreases in South China andincreases in North China, the Sichuan Basin, and the southeastern coastal areas, which is directly related to the population changes. The differentfuture changes of HDD and CDD when considering and disregarding the effects of population show that population distribution plays animportant role in energy consumption, which should be considered in future research.
基金supported by the National Natural Science Foundation of China (Grant No.42171311)the Open Fund of State Key Laboratory of Remote Sensing Science (Grant No.OFSLRSS202218)+1 种基金the Key Research and Development Program of the Hainan Province,China (Grant No.ZDYF2021SHFZ105)the Training Program of Excellent Master Thesis of Zhejiang Ocean University.
文摘The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources.
文摘Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxin-associated gene A protein (CagA), encoded by the gene cagA. However, these variants have not been characterized in China, where gastric cancer is common. We investigated the diversity of CagA variants in H. pylori strains isolated from a Chinese population. The 3' variable region of cagA genes from 66 clinical isolates in China were amplified by polymerase chain reaction, sequenced, aligned, and analyzed. All 66 H. pylori strains were CagA-positive, of which 93.9% were East Asian type and the tyrosine phosphorylation motifs (TPMs) were EPIYA-ABD. The remainder was Western type, in which TPMs were EPIYA-ABC. Interestingly, two of sixty-two strains (3.2%) of the East Asian type were mutated into ESIYA-B, whereas all four Western type (100%) strains were mutated into EPIYT-B. Both of the two strains with Western-type CagA obtained from gastric cancer patients contained a distinguished mutation on the first residue following the EPIYA site in the EPIYA-A motif. The predominant CagA type in these H. pylori strains isolated from Chinese patients in China was East Asian, with TPMs EPIYA-ABD, and there existed mutations in both the East Asian and Western type CagA.
基金supported by the National Natural Science Foundation of China,No.30472241,90709031 and 30973796the Ministry of Science and Technology of China("973"Project),No.2007CB512505+1 种基金provided by the Foundation of Hainan Province,No.310054the Health Department of Hainan Province,Qiong-Wei-45
文摘In the present study, we examined the analgesic effect of repeated electroacupuncture at bilateral Zusanfi (ST36) and Yanglingquan (GB34) once a day for 14 consecutive days in a rat model of chronic sciatic nerve constriction injury-induced neuropathic pain. In addition, concomitant changes in calcium/calmodulin-dependent protein kinase II expression and synaptic ultrastructure of neurons in the hippocampal CA3 region were examined. The thermal pain threshold (paw withdrawal latency) was increased significantly in both groups at 2 weeks after electroacupuncture intervention compared with 2 days of electroacupuncture. In ovariectomized rats with chronic constriction injury, the analgesic effect was significantly reduced. Electroacupuncture for 2 weeks significantly diminished the injury-induced increase in synaptJc cleft width and thinning of the postsynaptJc density, and it significantly suppressed the down-regulation of intracellular calcium/ calmodulin-dependent protein kinase II expression in the hippocampal CA3 region. Repeated electroacupuncture intervention had a cumulative analgesic effect on injury-induced neuropathic pain reactions, and it led to synaptic remodeling of hippocampal neurons and upregulated calcium/calmodulin-dependent protein kJnase II expression in the hippocampal CA3 region.
基金Supported by the Polish Ministry of Science and Higher Education under the KNOW program and Foundation for Polish Science,No.POMOST/2013-8/5
文摘At the 3' end of genomic hepatitis C virus(HCV) RNA there is a highly conserved untranslated region,the 3'X-tail,which forms part of the 3'UTR.This region plays key functions in regulation of critical processes of the viral life cycle.The 3'X region is essential for viral replication and infectivity.It is also responsible for regulation of switching between translation and transcription of the viral RNA.There is some evidence indicating the contribution of the 3'X region to the translation efficiency of the viral polyprotein and to the encapsidation process.Several different secondary structure models of the 3'X region,based on computer predictions and experimental structure probing,have been proposed.It is likely that the 3'X region adopts more than one structural form in infected cells and that a specific equilibrium between the various forms regulates several aspects of the viral life cycle.The most intriguing explanations of the structural heterogeneity problem of the 3'X region came with the discovery of its involvement in long-range RNA-RNA interactions and the potential for homodimer formation.This article summarizes current knowledge on the structure and function of the 3'X region of hepatitis C genomic RNA,reviews previous opinions,presents new hypotheses and summarizes the questions that still remain unanswered.
基金supported by two research grants of Associate Professor Dr.W.Attatippaholkun:Grant No.493-5600-G-00-3461,Program in Science and Technology Cooperation,Human Capacity Development,Bureau for Global Programs,Field Support and Research,US Agency for International Development,Washington,DCThe Royal Golden Jubilee-Ph.D Program,Thailand Research Fund,Thailand
文摘Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok during 24 year-evolution(1977-2000) comparing to the DEN3prototype(H87).Methods:The 5'UTRs of these Thai DEN3 and the H87 prototype were amplified by RT-PCR and sequenced.Their multiple sequence alignments were done by Codon Code Aligner v 4.0.4 software and their RNA secondary structures were predicted by MFOLD software.Replication of five Thai DEN3 candidates comparing to the 1187 prototype were done in human(HepG2) and the mosquito(C6/36) cell lines.Results:Among these Thai DEN3,the completely identical sequences of their first 89 nucleotides,their high-order secondary structure of 5'UTRs and three SNPs including the predominant C90 T,and two minor SNPs including A109 G and A112 G were found.The C90 T of Thai DEN3.Bangkok isolates was shown predominantly before 1977.Five Thai DEN3 candidates with the predominant C90 T were shown to replicate in human(HepG2) and the mosquito(C6/36) cell lines better than the H87 prototype.However,their highly conserved sequences as well as SNPs of the 5'UTR did not appear to correlate with their disease severity in human.Conclusions:Our findings highlighted evolutionary relationship of the completely identical 89 nucleotide sequence,the high-order secondary structure and the predominant C90 T of the 5'UTR of these Thai DEN3 during 24 year-evolution further suggesting to be their genetic markers and magic targets for future research on antiviral therapy as well as vaccine approaches of Thai DEN3.
基金the grants from the National Natural Science Foundation of China(U1805232,31770156,and 32172365)the China Postdoctoral Science Foundation(2021M690637)。
文摘The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation of these genes remain largely unknown.Here,through comparative transcriptome and chromatin immunoprecipitation sequencing(ChIP-seq)analyses of the methyltransferase PoKmt6 in rice blast fungus Pyricularia oryzae(syn.Magnaporthe oryzae),we found that PoKmt6-mediated H3K27me3 deposition was enriched mainly at fast-evolving regions and contributed to the silencing of a subset of secreted proteins(SP)and transposable element(TE)families during the vegetative growth of P.oryzae.Intriguingly,we observed that a group of SP genes,which were depleted of H3K27me3 modification,could also be silenced via the H3K27me3-mediated repression of the nearby TEs.In conclusion,our results indicate that H3K27me3 modification mediated by PoKmt6 regulates the expression of some SP genes in fast-evolving regions through the suppression of nearby TEs.
文摘Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein coding regions in DNA sequences is based on the period-3 property exhibited by nucleotides in exons. Several approaches based on signal processing tools and numerical representations have been applied to solve this problem, trying to achieve more accurate predictions. This paper presents a new indicator sequence based on amino acid sequence, called as aminoacid indicator sequence, derived from DNA string that uses the existing signal processing based time-domain and frequency domain methods to predict these regions within the billions long DNA sequence of eukaryotic cells which reduces the computational load by one-third. It is known that each triplet of bases, called as codon, instructs the cell machinery to synthesize an amino acid. The codon sequence therefore uniquely identifies an amino acid sequence which defines a protein. Thus the protein coding region is attributed by the codons in amino acid sequence. This property is used for detection of period-3 regions using amino acid sequence. Physico-chemical properties of amino acids are used for numerical representation. Various accuracy measures such as exonic peaks, discriminating factor, sensitivity, specificity, miss rate, wrong rate and approximate correlation are used to demonstrate the efficacy of the proposed predictor. The proposed method is validated on various organisms using the standard data-set HMR195, Burset and Guigo and KEGG. The simulation result shows that the proposed method is an effective approach for protein coding prediction.