The morphology of inflorescences is regulated in part by the temporal and spatial events that regulate flower specification.In Arabidopsis,an endogenous flowering time pathway mediated by a subset of SQUAMOSA PROMOTER...The morphology of inflorescences is regulated in part by the temporal and spatial events that regulate flower specification.In Arabidopsis,an endogenous flowering time pathway mediated by a subset of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE(SPL)transcription factors,including SPL3,SPL4,and SPL5,function to specify flowers by activating floral meristem identity genes.During shoot development,SPL3,SPL4,and SPL5 are post-transcriptionally regulated by microRNA156(miR156).The photoperiod regulated florigenic signal,FLOWERING LOCUS T(FT),promotes floral induction,in part by activating SPL3,SPL4,and SPL5.In turn,these SPLs function in parallel with FT to specify flower meristems.Two related BELLl-like homeobox genes PENNYWISE(PNY)and POUND-FOOLISH(PNF)expressed in the shoot apical meristem are absolutely required for the specification of floral meristems.Genetic studies show that the floral specification function of FT depends upon PNYand PNF;however,the interplay between these homeodomain proteins and SPLs is not known.In this manuscript,we show that the photoperiodic floral induction of SPL3,SPL4,and SPL5 is dependent upon PNY and PNE Further,PNY and PNF also control SPL3,SPL4,and SPL5 expression by negatively regulating miR156.Lastly,ectopic expres-sion of SPL4 partially rescues the pny pnf non-flower-producing phenotype,while overexpression of SPL3 or SPL5 in pny pnf plants was unable to restore flower specification.These results suggest that:(1)SPL3,SPL4,and SPL5 function is dependent upon PNY and PNF,or(2)expression of multiple SPLs is required for floral specification in pny pnf plants.展开更多
Personalized medicine will improve heath outcomes and patient satisfaction. However, implementing personalized medicine based on individuals’ biological information is far from simple, requiring genetic biomarkers th...Personalized medicine will improve heath outcomes and patient satisfaction. However, implementing personalized medicine based on individuals’ biological information is far from simple, requiring genetic biomarkers that are mainly developed and used by the pharmaceutical companies for selecting those patients who benefit more, or have less risk of adverse drug reactions, from a particular drug. Genome-wide Association Studies (GWAS) aim to identify genetic variants across the human genome that might be utilized as genetic biomarkers for diagnosis and prognosis. During the last several years, high-density genotyping SNP arrays have facilitated GWAS that successfully identified common genetic variants associated with a variety of phenotypes. However, each of the identified genetic variants only explains a very small fraction of the underlying genetic contribution to the studied phenotypic trait. The replication studies demonstrated that only a small portion of associated loci in the initial GWAS can be replicated, even within the same populations. Given the complexity of GWAS, multiple sources of Type I (false positive) and Type II (false negative) errors exist. The inconsistency in genotypes that caused either by the genotypeing experiment or by genotype calling process is a major source of the false GWAS findings. Accurate and reproducible genotypes are paramount as inconsistency in genotypes can lead to an inflation of false associations. This article will review the sources of inconsistency in genotypes and discuss its effect in GWAS findings.展开更多
Background and Aims:The perinatal transmission of hepatitis B virus(HBV)remains an important global health problem.Here,a systematic review and meta-analysis were conducted to evaluate the evidence regarding the effic...Background and Aims:The perinatal transmission of hepatitis B virus(HBV)remains an important global health problem.Here,a systematic review and meta-analysis were conducted to evaluate the evidence regarding the efficacy and maternal/fetal safety of treating pregnant women with lamivudine,telbivudine(LdT),and tenofovir(TDF).Methods:A PubMed and Scopus search resulted in 1,076 records,which were reduced to 36,containing 7,717 pregnant women with chronic HBV infection and 7467 infants meeting the inclusion criteria.The latest search was in August 2019.Results:Treatment with LdT,but not lamivudine and TDF,could significantly reduce the hepatitis B virus surface antigen-positive rate(odds ratio(OR)=0.37)in infants;it also led to higher rates of hepatitis B e antigen loss(OR=12.14),hepatitis B e antigen seroconversion(OR=8.93),and alanine aminotransferase normalization in mothers(OR=1.49).Each of these treatments was able to significantly reduce HBV DNA positivity at birth(total OR=0.19)and mother-to-child-transmission of HBV(total OR=0.15),and to cause higher rates of HBV DNA suppression in mothers(total OR=25.53).However,nucleos(t)ide analogues might also be involved in creatine kinase elevation(total OR=7.48).In contrast,no significant association was found between nucleos(t)ide analogue therapy and preterm/premature births,congenital malformation,low birth weight,and abortion or fetal/infant death.The results suggested LdT's high capability of preventing mother-to-childtransmission.However,TDF failed to show significant associations to a reduced risk of mother-to-child-transmission,probably due to the low number of patients included.Conclusions:Although using either lamivudine,LdT,orTDF could lead to more favorable maternal/fetal outcomes,LdT seemed to show more potential in resolving certain infant-and maternal-related outcomes.More studies on the safety profile of such treatments are required.展开更多
Plants are constantly under attack by pathogens,pests,and parasites,resulting in severe consequences on global food production and human health.While pathogens and pests find their ways to invade and communicate with ...Plants are constantly under attack by pathogens,pests,and parasites,resulting in severe consequences on global food production and human health.While pathogens and pests find their ways to invade and communicate with their hosts,plants have evolved sophisticated immune systems to fight infections.展开更多
文摘The morphology of inflorescences is regulated in part by the temporal and spatial events that regulate flower specification.In Arabidopsis,an endogenous flowering time pathway mediated by a subset of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE(SPL)transcription factors,including SPL3,SPL4,and SPL5,function to specify flowers by activating floral meristem identity genes.During shoot development,SPL3,SPL4,and SPL5 are post-transcriptionally regulated by microRNA156(miR156).The photoperiod regulated florigenic signal,FLOWERING LOCUS T(FT),promotes floral induction,in part by activating SPL3,SPL4,and SPL5.In turn,these SPLs function in parallel with FT to specify flower meristems.Two related BELLl-like homeobox genes PENNYWISE(PNY)and POUND-FOOLISH(PNF)expressed in the shoot apical meristem are absolutely required for the specification of floral meristems.Genetic studies show that the floral specification function of FT depends upon PNYand PNF;however,the interplay between these homeodomain proteins and SPLs is not known.In this manuscript,we show that the photoperiodic floral induction of SPL3,SPL4,and SPL5 is dependent upon PNY and PNE Further,PNY and PNF also control SPL3,SPL4,and SPL5 expression by negatively regulating miR156.Lastly,ectopic expres-sion of SPL4 partially rescues the pny pnf non-flower-producing phenotype,while overexpression of SPL3 or SPL5 in pny pnf plants was unable to restore flower specification.These results suggest that:(1)SPL3,SPL4,and SPL5 function is dependent upon PNY and PNF,or(2)expression of multiple SPLs is required for floral specification in pny pnf plants.
文摘Personalized medicine will improve heath outcomes and patient satisfaction. However, implementing personalized medicine based on individuals’ biological information is far from simple, requiring genetic biomarkers that are mainly developed and used by the pharmaceutical companies for selecting those patients who benefit more, or have less risk of adverse drug reactions, from a particular drug. Genome-wide Association Studies (GWAS) aim to identify genetic variants across the human genome that might be utilized as genetic biomarkers for diagnosis and prognosis. During the last several years, high-density genotyping SNP arrays have facilitated GWAS that successfully identified common genetic variants associated with a variety of phenotypes. However, each of the identified genetic variants only explains a very small fraction of the underlying genetic contribution to the studied phenotypic trait. The replication studies demonstrated that only a small portion of associated loci in the initial GWAS can be replicated, even within the same populations. Given the complexity of GWAS, multiple sources of Type I (false positive) and Type II (false negative) errors exist. The inconsistency in genotypes that caused either by the genotypeing experiment or by genotype calling process is a major source of the false GWAS findings. Accurate and reproducible genotypes are paramount as inconsistency in genotypes can lead to an inflation of false associations. This article will review the sources of inconsistency in genotypes and discuss its effect in GWAS findings.
文摘Background and Aims:The perinatal transmission of hepatitis B virus(HBV)remains an important global health problem.Here,a systematic review and meta-analysis were conducted to evaluate the evidence regarding the efficacy and maternal/fetal safety of treating pregnant women with lamivudine,telbivudine(LdT),and tenofovir(TDF).Methods:A PubMed and Scopus search resulted in 1,076 records,which were reduced to 36,containing 7,717 pregnant women with chronic HBV infection and 7467 infants meeting the inclusion criteria.The latest search was in August 2019.Results:Treatment with LdT,but not lamivudine and TDF,could significantly reduce the hepatitis B virus surface antigen-positive rate(odds ratio(OR)=0.37)in infants;it also led to higher rates of hepatitis B e antigen loss(OR=12.14),hepatitis B e antigen seroconversion(OR=8.93),and alanine aminotransferase normalization in mothers(OR=1.49).Each of these treatments was able to significantly reduce HBV DNA positivity at birth(total OR=0.19)and mother-to-child-transmission of HBV(total OR=0.15),and to cause higher rates of HBV DNA suppression in mothers(total OR=25.53).However,nucleos(t)ide analogues might also be involved in creatine kinase elevation(total OR=7.48).In contrast,no significant association was found between nucleos(t)ide analogue therapy and preterm/premature births,congenital malformation,low birth weight,and abortion or fetal/infant death.The results suggested LdT's high capability of preventing mother-to-childtransmission.However,TDF failed to show significant associations to a reduced risk of mother-to-child-transmission,probably due to the low number of patients included.Conclusions:Although using either lamivudine,LdT,orTDF could lead to more favorable maternal/fetal outcomes,LdT seemed to show more potential in resolving certain infant-and maternal-related outcomes.More studies on the safety profile of such treatments are required.
文摘Plants are constantly under attack by pathogens,pests,and parasites,resulting in severe consequences on global food production and human health.While pathogens and pests find their ways to invade and communicate with their hosts,plants have evolved sophisticated immune systems to fight infections.
