[Objective] The aim of the study was to make research on genomic struc- ture variation and variety analysis of Dongxiang wild rice. [Method] Introgression groups of BC1F6 were based on donor of Oryza rufipogon Griff. ...[Objective] The aim of the study was to make research on genomic struc- ture variation and variety analysis of Dongxiang wild rice. [Method] Introgression groups of BC1F6 were based on donor of Oryza rufipogon Griff. and receptor of O. sativa sp. indica Kate. Strains of 239 in the group were analyzed on Polymor- phism with the help of 25 couples of SSR primers distributed in 12 pairs of chromo- somes. [Result] Gene fragments of O. rufipogon Griff. were found penetrated in the 25 microsatellite sites and most of the groups kept the parents of Xieqinzao B or DNA sequence of O. rufipogon Griff. The average rate of recurrent homozygous bands was 78.13% in the ILs, but the highest was 94.98% （amplified by primer RM131） and the lowest was 60.25% （RM171）. The average rate of donor homozy- gous bands was 13.37%, but the highest was 32.64% （RM171） and the lowest was 2.93% （RM1095）. There were numerous heterozygous sites in the population and the average heterozygosis rate was 5.62%, while the highest was 10.04%（RM401）. Moreover, we found some parental fragments were lost and some novel fragments were not detected in either parent in BC1F6 population. The average rate of lost bands was 2.88%, while the highest was 13.39% （RM311） and the lowest was 0 （RM401）. The average rate of new bands was 1%. The average of Nei＇s gene di- versity （He） and Shannon＇s Information index （I） were 0.276 and 0.457 respectively in high generation of introgression lines. [Conclusion] The study demonstrated that distant hybridization led to extensive genetic and epigenetic variations in high gener- ation of introgression lines, which expanded the base of genetic variation and laid an important foundation for rice improvement and germplasm innovation.展开更多
AIM: To investigate the changes of histology and expression of MMP-2 and nm23-H1 in primary and metastatic gastric cancer. METHODS: One hundred and seventy-seven gastric cancer patients with lymph node and/or distal m...AIM: To investigate the changes of histology and expression of MMP-2 and nm23-H1 in primary and metastatic gastric cancer. METHODS: One hundred and seventy-seven gastric cancer patients with lymph node and/or distal metastasis between 1997 and 2001 were reviewed. Differences in histology of the primary and metastatic gastric cancer were assessed. MMP-2 and nm23-H1 immunoreactivity was compared in 44 patients with tumor infiltration to the serosa layer. RESULTS: Poorly and moderately differentiated metastatic gastric cancer was found in 88.7% (157/177) and primary gastric cancer in 75.7% (134/177) of the patients. The histological type of metastatic gastric cancer that was not completely in accordance with the preponderant histology of primary gastric cancer was observed in 25 patients (14.1%). MMP-2 immunoreactivity in metastatic gastric cancer was significantly stronger than that in primary gastric cancer, while nm23-H1 immunoreactivity showed no difference in primary and metastatic gastric cancer. CONCLUSION: Metastatic gastric cancer presents more aggressive histological morphology and higher MMP-2 immunoreactivity than primary gastric cancer. This heterogeneity may elicit a possible mechanism of gastric cancer metastasis.展开更多
AIM： To investigate the incidence of KIT immunohostochemical staining in （GI） stromal tumors （GISTs）, and to analyze the clinical manifestations of the tumors and prognostic indicators. METHODS： We retrospective...AIM： To investigate the incidence of KIT immunohostochemical staining in （GI） stromal tumors （GISTs）, and to analyze the clinical manifestations of the tumors and prognostic indicators. METHODS： We retrospectively analyzed 50 cases of previously diagnosed GISTs. Tissue samples were assessed with KIT （CDl17 antigen）, CD34, SMA, desmin, S-100, NSE, PCNA, Ki-67, and BCL-2 for immunohistochemical study and pathological characteristics were analyzed for prognostic factors. RESULTS： Fifteen tumors （30%） were negative in KIT staining. A significant association was observed between gender （male patients： 14/15） and KIT-negative staining （P = 0.003）.The patients＇s mean age was 56.6 years. Tumors developed in stomach （n = 8）, small intestine （n = 5）, large intestine （n = 1） and oesophagus （n = 1）. The mean tumor size was 5.72 cm. The mitotic count ranged from 0-29/50 HPF （mean： 3.4） and 73% of tumors showed no necrosis. The majority of the tumors （67%） had dual or epithelioid differentiation. Tumors were classified as very low or low risk （n = 7）, intermediate risk （n = 5）, and high risk （n = 3） groups. Twelve （80%） patients were alive without evidence of residual tumor for an average period of 40.25 mo （12-82 too）; three patients developed metastatic disease to the liver and eventually died within 2-12 mo （median survival： 8.6 too）.CONCLUSION： A small subgroup of GISTs fulfils the clinical and morphological criteria of these tumors, and lacks KIT expression. These tumors predominantly developed in the stomach, being dual or epithelioid in morphology, which are classified as low risk tumors and presented a better survival status than KIT-positive tumors. The ability to diagnose GISTs still depends on immunohistochemical staining but the research should extend in gene mutations.展开更多
Cyanophages are double-stranded DNA viruses that infect cyanobacteria, and they can be found in both freshwater and marine environments. They have a complex pattem of host ranges and play important roles in controllin...Cyanophages are double-stranded DNA viruses that infect cyanobacteria, and they can be found in both freshwater and marine environments. They have a complex pattem of host ranges and play important roles in controlling cyanobacteria population. Unlike marine cyanophages, for which there have been a number of recent investigations, very little attention has been paid to freshwater cyanophages. This review summarizes the taxonomy and morphology, host range, distribution, seasonal dynamics, and complete genomes of freshwater cyanophages, as well as diagnostic markers that can be used to identify them.展开更多
The actinomycete populations and functions in cadmium （Cd） contaminated soil were investigated by the cultivation- independent molecular methods. The genomic DNA was extracted and purified from soil adulterated with...The actinomycete populations and functions in cadmium （Cd） contaminated soil were investigated by the cultivation- independent molecular methods. The genomic DNA was extracted and purified from soil adulterated with various con- centrations of Cd in the laboratory. The partial 16S rDNA genes were amplified by polymerase chain reaction （PCR） using specific primers bound to evolutionarily conserved regions within these actinomycete genes. The diversity in PCR- amplified products, as measured by denaturing gradient gel electrophoresis （EGGE）, was used as a genetic fingerprint of the population. Principle component analysis and Shannon-Weaver diversity index （H） analyses were used to analyze the DGGE results. Results showed that the two principal components accounted for only a low level of the total variance. The value H in contaminated soil was lower than that in the control at later stages of cultivation, whereas at earlier stages it was higher. Among the six sampling time points, the first, fifth and sixth weeks had the highest values of H. Significantly negative correlations between bioavallable Cd concentration and H values existed in the samples from weeks 2 （R = 0.929, P 〈 0.05） and 4 （R = 0.909, P 〈 0.05）. These results may shed light on the effect of Cd on the soil environment and the chemical behavior and toxicity of Cd to actinomycetes.展开更多
Both exercise and aging increase reactive oxygen species （ROS）, which can result in damage to cells. Aging is the result of damage caused by ROS to the mitochondrial genome in post mitotic cells and numerous studies...Both exercise and aging increase reactive oxygen species （ROS）, which can result in damage to cells. Aging is the result of damage caused by ROS to the mitochondrial genome in post mitotic cells and numerous studies have demonstrated an increase in ROS or their byproducts with exercise. ROS can cause oxidative stress as they overwhelm the antioxidant cellular defenses. Therefore interventions aimed at limiting or inhibiting ROS production, such as supplementation with antioxidant vitamins, should be able to reduce fatigue during muscle contraction and the rate of formation of aging changes with a consequent reduction of the aging rate and disease pathogenesis. However, it has been shown that ROS are essential signaling molecules which are required to promote the health benefits of exercise and longevity. In young individuals, ROS are required for normal force production in skeletal muscle, for the development of training-induced adaptations in endurance performance, as well as for the induction of the endogenous defense systems. Thus, taking antioxidants during training, in young athletes, seems to be detrimental. However, antioxidant supplementation may be expected to be beneficial and is receiving growing attention in the active old population. In this manuscript we review the literature associated with the main areas of interest in this topic.展开更多
Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene f...Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene flow via larval dispersal. Here we review and discuss 4 mechanisms that could generate such unexpected patterns： selection, sweepstakes reproductive success, collective dispersal, and temporal shifts in local population dynamics. First, we review examples where genetic differentiation at specific loci was driven by diversifying selection, which was historically the first process invoked to explain CGP. Second, we turn to neutral demographic processes that may drive genome-wide effects, and whose effects on CGP may be enhanced when they act together. We discuss how sweepstakes reproductive success accelerates genetic drift and can thus generate genetic structure, provided that gene flow is not too strong. Collective dispersal is another mechanism whereby genetic structure can be maintained regardless of dispersal intensity, because it may prevent larval cohorts from becoming entirely mixed. Theoretical analyses of both the sweepstakes and the collective dispersal ideas are presented. Finally, we discuss an idea that has received less attention than the other ones just mentioned, namely temporal shifts in local population dynamics.展开更多
基金partially supported by National Natural Science Foundation of China(30860120,30900781)Science and Technology Projects of Jiangxi Education Department(GJJ09464)Natural Science Foundation of Jiangxi(2008GQN0059)~~
文摘[Objective] The aim of the study was to make research on genomic struc- ture variation and variety analysis of Dongxiang wild rice. [Method] Introgression groups of BC1F6 were based on donor of Oryza rufipogon Griff. and receptor of O. sativa sp. indica Kate. Strains of 239 in the group were analyzed on Polymor- phism with the help of 25 couples of SSR primers distributed in 12 pairs of chromo- somes. [Result] Gene fragments of O. rufipogon Griff. were found penetrated in the 25 microsatellite sites and most of the groups kept the parents of Xieqinzao B or DNA sequence of O. rufipogon Griff. The average rate of recurrent homozygous bands was 78.13% in the ILs, but the highest was 94.98% （amplified by primer RM131） and the lowest was 60.25% （RM171）. The average rate of donor homozy- gous bands was 13.37%, but the highest was 32.64% （RM171） and the lowest was 2.93% （RM1095）. There were numerous heterozygous sites in the population and the average heterozygosis rate was 5.62%, while the highest was 10.04%（RM401）. Moreover, we found some parental fragments were lost and some novel fragments were not detected in either parent in BC1F6 population. The average rate of lost bands was 2.88%, while the highest was 13.39% （RM311） and the lowest was 0 （RM401）. The average rate of new bands was 1%. The average of Nei＇s gene di- versity （He） and Shannon＇s Information index （I） were 0.276 and 0.457 respectively in high generation of introgression lines. [Conclusion] The study demonstrated that distant hybridization led to extensive genetic and epigenetic variations in high gener- ation of introgression lines, which expanded the base of genetic variation and laid an important foundation for rice improvement and germplasm innovation.
文摘AIM: To investigate the changes of histology and expression of MMP-2 and nm23-H1 in primary and metastatic gastric cancer. METHODS: One hundred and seventy-seven gastric cancer patients with lymph node and/or distal metastasis between 1997 and 2001 were reviewed. Differences in histology of the primary and metastatic gastric cancer were assessed. MMP-2 and nm23-H1 immunoreactivity was compared in 44 patients with tumor infiltration to the serosa layer. RESULTS: Poorly and moderately differentiated metastatic gastric cancer was found in 88.7% (157/177) and primary gastric cancer in 75.7% (134/177) of the patients. The histological type of metastatic gastric cancer that was not completely in accordance with the preponderant histology of primary gastric cancer was observed in 25 patients (14.1%). MMP-2 immunoreactivity in metastatic gastric cancer was significantly stronger than that in primary gastric cancer, while nm23-H1 immunoreactivity showed no difference in primary and metastatic gastric cancer. CONCLUSION: Metastatic gastric cancer presents more aggressive histological morphology and higher MMP-2 immunoreactivity than primary gastric cancer. This heterogeneity may elicit a possible mechanism of gastric cancer metastasis.
基金Supported by Hellenic State Scholarship Foundation, Department of Science Promotion, No. 19366/2005
文摘AIM： To investigate the incidence of KIT immunohostochemical staining in （GI） stromal tumors （GISTs）, and to analyze the clinical manifestations of the tumors and prognostic indicators. METHODS： We retrospectively analyzed 50 cases of previously diagnosed GISTs. Tissue samples were assessed with KIT （CDl17 antigen）, CD34, SMA, desmin, S-100, NSE, PCNA, Ki-67, and BCL-2 for immunohistochemical study and pathological characteristics were analyzed for prognostic factors. RESULTS： Fifteen tumors （30%） were negative in KIT staining. A significant association was observed between gender （male patients： 14/15） and KIT-negative staining （P = 0.003）.The patients＇s mean age was 56.6 years. Tumors developed in stomach （n = 8）, small intestine （n = 5）, large intestine （n = 1） and oesophagus （n = 1）. The mean tumor size was 5.72 cm. The mitotic count ranged from 0-29/50 HPF （mean： 3.4） and 73% of tumors showed no necrosis. The majority of the tumors （67%） had dual or epithelioid differentiation. Tumors were classified as very low or low risk （n = 7）, intermediate risk （n = 5）, and high risk （n = 3） groups. Twelve （80%） patients were alive without evidence of residual tumor for an average period of 40.25 mo （12-82 too）; three patients developed metastatic disease to the liver and eventually died within 2-12 mo （median survival： 8.6 too）.CONCLUSION： A small subgroup of GISTs fulfils the clinical and morphological criteria of these tumors, and lacks KIT expression. These tumors predominantly developed in the stomach, being dual or epithelioid in morphology, which are classified as low risk tumors and presented a better survival status than KIT-positive tumors. The ability to diagnose GISTs still depends on immunohistochemical staining but the research should extend in gene mutations.
文摘Cyanophages are double-stranded DNA viruses that infect cyanobacteria, and they can be found in both freshwater and marine environments. They have a complex pattem of host ranges and play important roles in controlling cyanobacteria population. Unlike marine cyanophages, for which there have been a number of recent investigations, very little attention has been paid to freshwater cyanophages. This review summarizes the taxonomy and morphology, host range, distribution, seasonal dynamics, and complete genomes of freshwater cyanophages, as well as diagnostic markers that can be used to identify them.
基金Project supported by the National Natural Science Foundation of China (Nos. 30570053 and 40501037)the National High Technology Research and Development Program (863 Program) of China (No. 2007AA10Z409)+1 种基金the National"Eleventh Five Years Plan" Key Project on Science and Technology of China (No. 2006BAJ08B01)the Research Fund of Science and Technology Bureau of Zhejiang Province,China (No. 2008C23088)
文摘The actinomycete populations and functions in cadmium （Cd） contaminated soil were investigated by the cultivation- independent molecular methods. The genomic DNA was extracted and purified from soil adulterated with various con- centrations of Cd in the laboratory. The partial 16S rDNA genes were amplified by polymerase chain reaction （PCR） using specific primers bound to evolutionarily conserved regions within these actinomycete genes. The diversity in PCR- amplified products, as measured by denaturing gradient gel electrophoresis （EGGE）, was used as a genetic fingerprint of the population. Principle component analysis and Shannon-Weaver diversity index （H） analyses were used to analyze the DGGE results. Results showed that the two principal components accounted for only a low level of the total variance. The value H in contaminated soil was lower than that in the control at later stages of cultivation, whereas at earlier stages it was higher. Among the six sampling time points, the first, fifth and sixth weeks had the highest values of H. Significantly negative correlations between bioavallable Cd concentration and H values existed in the samples from weeks 2 （R = 0.929, P 〈 0.05） and 4 （R = 0.909, P 〈 0.05）. These results may shed light on the effect of Cd on the soil environment and the chemical behavior and toxicity of Cd to actinomycetes.
基金supported by grants SAF2010-19498 from the Spanish Ministry of Education and Science(MEC(gsl))ISCIII2006-RED13-027 from the Red Tematica de investigacion cooperativa en envejecimiento y fragilidad (RETICEF(gs2))+3 种基金P2011/02 RM from Catedra Real Madrid-UEM (gs3)PROMETEO2010/074 from Conselleria de Sanitat de la Generalitat Valenciana(gs4)35NEURO Gentx Gent from Fundacio Gent Per Gent de la Comunitat Valenciana(gs5) and EU(gs6) Funded COSTB35 and CM 1001co-financed by funds from the European Union
文摘Both exercise and aging increase reactive oxygen species （ROS）, which can result in damage to cells. Aging is the result of damage caused by ROS to the mitochondrial genome in post mitotic cells and numerous studies have demonstrated an increase in ROS or their byproducts with exercise. ROS can cause oxidative stress as they overwhelm the antioxidant cellular defenses. Therefore interventions aimed at limiting or inhibiting ROS production, such as supplementation with antioxidant vitamins, should be able to reduce fatigue during muscle contraction and the rate of formation of aging changes with a consequent reduction of the aging rate and disease pathogenesis. However, it has been shown that ROS are essential signaling molecules which are required to promote the health benefits of exercise and longevity. In young individuals, ROS are required for normal force production in skeletal muscle, for the development of training-induced adaptations in endurance performance, as well as for the induction of the endogenous defense systems. Thus, taking antioxidants during training, in young athletes, seems to be detrimental. However, antioxidant supplementation may be expected to be beneficial and is receiving growing attention in the active old population. In this manuscript we review the literature associated with the main areas of interest in this topic.
文摘Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene flow via larval dispersal. Here we review and discuss 4 mechanisms that could generate such unexpected patterns： selection, sweepstakes reproductive success, collective dispersal, and temporal shifts in local population dynamics. First, we review examples where genetic differentiation at specific loci was driven by diversifying selection, which was historically the first process invoked to explain CGP. Second, we turn to neutral demographic processes that may drive genome-wide effects, and whose effects on CGP may be enhanced when they act together. We discuss how sweepstakes reproductive success accelerates genetic drift and can thus generate genetic structure, provided that gene flow is not too strong. Collective dispersal is another mechanism whereby genetic structure can be maintained regardless of dispersal intensity, because it may prevent larval cohorts from becoming entirely mixed. Theoretical analyses of both the sweepstakes and the collective dispersal ideas are presented. Finally, we discuss an idea that has received less attention than the other ones just mentioned, namely temporal shifts in local population dynamics.
