Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical studies.In this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)...Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical studies.In this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was proposed.The introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce nce.There fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 nm.Furthermore,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio n.Confocal laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell morphology.In addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa cells.Organ imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and spleen.Together,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.展开更多
In several stress responsive gene loci of monocot cereal crops,we have previously identified an unusual posttranscriptional processing mediated by paired presence of short direct repeated （SDR） sequences at 5＇ and ...In several stress responsive gene loci of monocot cereal crops,we have previously identified an unusual posttranscriptional processing mediated by paired presence of short direct repeated （SDR） sequences at 5＇ and 3＇ splicing junctions that are distinct from conventional （U2/U12-type） splicing boundaries.By using the known SDR-containing sequences as probes,24 plant candidate genes involved in diverse functional pathways from both monocots and dicots that potentially possess SDR-mediated posttranscriptional processing were predicted in the GenBank database.The SDRs-mediated posttranscriptional processing events including cis-and trans-actions were experimentally detected in majority of the predicted candidates.Extensive sequence analysis demonstrates several types of SDR-associated splicing peculiarities including partial exon deletion,exon fragment repetition,exon fragment scrambling and trans-splicing that result in either loss of partial exon or unusual exonic sequence rearrangements within or between RNA molecules.In addition,we show that the paired presence of SDR is necessary but not sufficient in SDR-mediated splicing in transient expression and stable transformation systems.We also show prokaryote is incapable of SDR-mediated premRNA splicing.展开更多
Compared with traditional materials,metal-organic framework materials(MOFs)have the characteristics of drug release controllability,degradability,designability and adjustability of composition and structure,excellent ...Compared with traditional materials,metal-organic framework materials(MOFs)have the characteristics of drug release controllability,degradability,designability and adjustability of composition and structure,excellent load capacity,and designability and adjustability of channel shape and size,and have shown a wide range of application value in the field of biomedicine.In this paper,based on the structural characteristics of MOFs,the synthetic design of MOF materials was expounded,and the research achievements of MOF materials in biomedicine in recent years were reviewed.展开更多
The interannual variability in precipitation during the pre-rainy season(PRS) in South China is significantly correlated with Eurasian snow cover. This study elucidates the distinct mechanisms by which Eurasian snow c...The interannual variability in precipitation during the pre-rainy season(PRS) in South China is significantly correlated with Eurasian snow cover. This study elucidates the distinct mechanisms by which Eurasian snow cover anomalies in March influence precipitation during the early(pre-monsoon) and late(post-monsoon) PRS. In the early PRS, anomalous snow cover in the western region of Eastern Europe(WEE) triggers a southeastward-propagating wave train that impacts Central Asia.The teleconnection pattern induces anomalous cyclonic circulation in Central Asia, which reinforces the midlatitude zonal wind,contributing to the zonal wind wave train pattern towards East Asia. As a result, the East Asian subtropical westerly jet and the western North Pacific subtropical high are enhanced, and the related upper-level divergence, ascending motion, and moisture convergence in South China are intensified, collectively promoting precipitation there. In contrast, during the late PRS, increased snow cover across the eastern sector of Eastern Europe(EEE) and the region east of Lake Baikal(ELB) inhibit South China's precipitation. The wave pattern associated with the EEE(ELB) snow anomaly propagates southeastwards(southwards) to lower latitudes, intensifying the western North Pacific subtropical high. Furthermore, the perturbation stemming from the ELB region induces negative geopotential height anomalies aloft and amplifies the baroclinic anticyclone over the western Pacific. This resulted in prevailing subsidence over South China, which in turn suppresses precipitation during the late PRS. Numerical experiments corroborate the observed circulation adjustments and precipitation responses to snow cover anomalies in the two periods, lending credence to the proposed mechanisms.展开更多
Malaria is one of the three most hazardous infectious dis- eases （HIV/AIDS, Malaria and tuberculosis） in the world. Since 1960, falciparum malaria gradually became resistant to original antimalarial drugs such as Ch...Malaria is one of the three most hazardous infectious dis- eases （HIV/AIDS, Malaria and tuberculosis） in the world. Since 1960, falciparum malaria gradually became resistant to original antimalarial drugs such as Chloroquine and Fan- sidar. With the global spread of drug-resistant falciparum malaria, morbidity and mortality increased greatly. In May of 2014, the World Health Organization （WHO） announced that the drug combination with artemisinin-based compound is by far the only effective drug around the world in the treatment of falciparum malaria.展开更多
基金Project supported by the Natural Science Basic Research Program of Shaanxi Province(2021JZ-43)the Key Program for International Science and Technology Cooperation Projects of Shaanxi Province(2018KWZ-08)+2 种基金the National Key Research and Development Program of China(2019YFC1520904)the Scientific Research Plan of Shannxi Provincial Education Department,China(18JK0780)Ningxia Natural Fund(2023AAC03338)。
文摘Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical studies.In this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was proposed.The introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce nce.There fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 nm.Furthermore,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio n.Confocal laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell morphology.In addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa cells.Organ imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and spleen.Together,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.
基金supported by the National Key Basic Research Program (973 program) (No. 2006CB100205)the National Science Fund for Distinguished Young Scholars (No. 30825030)+2 种基金the National Natural Science Foundation of China (No. 30770466, 90717110, 30970260 and 30971752)the Earmarked Fund for Modern Agro-industry Technology Research System (No. nycytx-01)the National High Technology Research and Development Program of China (863 Program) (No. 2007AA10Z100)
文摘In several stress responsive gene loci of monocot cereal crops,we have previously identified an unusual posttranscriptional processing mediated by paired presence of short direct repeated （SDR） sequences at 5＇ and 3＇ splicing junctions that are distinct from conventional （U2/U12-type） splicing boundaries.By using the known SDR-containing sequences as probes,24 plant candidate genes involved in diverse functional pathways from both monocots and dicots that potentially possess SDR-mediated posttranscriptional processing were predicted in the GenBank database.The SDRs-mediated posttranscriptional processing events including cis-and trans-actions were experimentally detected in majority of the predicted candidates.Extensive sequence analysis demonstrates several types of SDR-associated splicing peculiarities including partial exon deletion,exon fragment repetition,exon fragment scrambling and trans-splicing that result in either loss of partial exon or unusual exonic sequence rearrangements within or between RNA molecules.In addition,we show that the paired presence of SDR is necessary but not sufficient in SDR-mediated splicing in transient expression and stable transformation systems.We also show prokaryote is incapable of SDR-mediated premRNA splicing.
基金Supported by Subproject of Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicine(GXZYKF2019-7).
文摘Compared with traditional materials,metal-organic framework materials(MOFs)have the characteristics of drug release controllability,degradability,designability and adjustability of composition and structure,excellent load capacity,and designability and adjustability of channel shape and size,and have shown a wide range of application value in the field of biomedicine.In this paper,based on the structural characteristics of MOFs,the synthetic design of MOF materials was expounded,and the research achievements of MOF materials in biomedicine in recent years were reviewed.
基金supported by the National Natural Science Foundation of China (Grant No. 42365004)the Natural Science Foundation of Guangxi Province(GrantNos. 2024GXNSFAA010211 & 2023GXNSFAA026511)the Research Foundation for Advanced Talents of Nanning Normal University。
文摘The interannual variability in precipitation during the pre-rainy season(PRS) in South China is significantly correlated with Eurasian snow cover. This study elucidates the distinct mechanisms by which Eurasian snow cover anomalies in March influence precipitation during the early(pre-monsoon) and late(post-monsoon) PRS. In the early PRS, anomalous snow cover in the western region of Eastern Europe(WEE) triggers a southeastward-propagating wave train that impacts Central Asia.The teleconnection pattern induces anomalous cyclonic circulation in Central Asia, which reinforces the midlatitude zonal wind,contributing to the zonal wind wave train pattern towards East Asia. As a result, the East Asian subtropical westerly jet and the western North Pacific subtropical high are enhanced, and the related upper-level divergence, ascending motion, and moisture convergence in South China are intensified, collectively promoting precipitation there. In contrast, during the late PRS, increased snow cover across the eastern sector of Eastern Europe(EEE) and the region east of Lake Baikal(ELB) inhibit South China's precipitation. The wave pattern associated with the EEE(ELB) snow anomaly propagates southeastwards(southwards) to lower latitudes, intensifying the western North Pacific subtropical high. Furthermore, the perturbation stemming from the ELB region induces negative geopotential height anomalies aloft and amplifies the baroclinic anticyclone over the western Pacific. This resulted in prevailing subsidence over South China, which in turn suppresses precipitation during the late PRS. Numerical experiments corroborate the observed circulation adjustments and precipitation responses to snow cover anomalies in the two periods, lending credence to the proposed mechanisms.
文摘Malaria is one of the three most hazardous infectious dis- eases （HIV/AIDS, Malaria and tuberculosis） in the world. Since 1960, falciparum malaria gradually became resistant to original antimalarial drugs such as Chloroquine and Fan- sidar. With the global spread of drug-resistant falciparum malaria, morbidity and mortality increased greatly. In May of 2014, the World Health Organization （WHO） announced that the drug combination with artemisinin-based compound is by far the only effective drug around the world in the treatment of falciparum malaria.
