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1.
Emerg Microbes Infect ; 13(1): 2324502, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38465692

RESUMO

In this study, we reported the first long-term monitoring of SARS-CoV-2 in wastewater in Mainland China from November 2021 to October 2023. The city of Shijiazhuang was employed for this case study. We developed a triple reverse transcription droplet digital PCR (RT-ddPCR) method using triple primer-probes for simultaneous detection of the N1 gene, E gene, and Pepper mild mottle virus (PMMoV) to achieve accurate quantification of SARS-CoV-2 RNA in wastewater. Both the RT-ddPCR method and the commercial multiplex reverse transcription quantitative polymerase chain reaction (RT-qPCR) method were implemented for the detection of SARS-CoV-2 in wastewater in Shijiazhuang City over a 24-month period. Results showed that SARS-CoV-2 was detected for the first time in the wastewater of Shijiazhuang City on 10 November 2022. The peak of COVID-19 cases occurred in the middle of December 2022, when the concentration of SARS-CoV-2 in the wastewater was highest. The trend of virus concentration increases and decreases forming a "long-tailed" shape in the COVID-19  outbreak and recession cycle. The results indicated that both multiplex RT-ddPCR and RT-qPCR are effective in detecting SARS-CoV-2 in wastewater, but RT-ddPCR is capable of detecting low concentrations of SARS-CoV-2 in wastewater which is more efficient. The SARS-CoV-2 abundance in wastewater is correlated to clinical data, outlining the public health utility of this work.HighlightsFirst long-term monitoring of SARS-CoV-2 in wastewater in Mainland ChinaCOVID-19 outbreak was tracked in Shijiazhuang City from outbreak to containmentWastewater was monitored simultaneously using RT-ddPCR and RT-qPCR methodsTriple primer-probe RT-ddPCR detects N1 and E genes of SARS-CoV-2 and PMMoV.


Assuntos
COVID-19 , SARS-CoV-2 , Tobamovirus , Humanos , SARS-CoV-2/genética , Águas Residuárias , COVID-19/diagnóstico , COVID-19/epidemiologia , RNA Viral/genética , China/epidemiologia , Reação em Cadeia da Polimerase Multiplex , Teste para COVID-19
2.
Adv Mater ; : e2313663, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38415854

RESUMO

2D <100>-oriented Dion-Jacobson or Ruddlesden-Popper perovskites are widely recognized as promising candidates for optoelectronic applications. However, the large interlayer spacing significantly hinders the carrier transport. <110>-oriented 2D perovskites naturally exhibit reduced interlayer spacings, but the tilting of metal halide octahedra is typically serious and leads to poor charge transport. Herein, a <110>-oriented 2D perovskite EPZPbBr4 (EPZ = 1-ethylpiperazine) with minimized tilting is designed through A-site stereo-hindrance engineering. The piperazine functional group enters the space enclosed by the three [PbBr6 ]4- octahedra, pushing Pb─Br─Pb closer to a straight line (maximum Pb─Br─Pb angle ≈180°), suppressing the tilting as well as electron-phonon coupling. Meanwhile, the ethyl group is located between layers and contributes an extremely reduced effective interlayer distance (2.22 Å), further facilitating the carrier transport. As a result, EPZPbBr4 simultaneously demonstrates high µτ product (1.8 × 10-3 cm2 V-1 ) and large resistivity (2.17 × 1010 Ω cm). The assembled X-ray detector achieves low dark current of 1.02 × 10-10 A cm-2 and high sensitivity of 1240 µC Gy-1 cm-2 under the same bias voltage. The realized specific detectivity (ratio of sensitivity to noise current density, 1.23 × 108 µC Gy-1 cm-1 A-1/2 ) is the highest among all reported perovskite X-ray detectors.

3.
J Biomol Struct Dyn ; 41(20): 11255-11261, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36625725

RESUMO

To measure the expression of angiotensin converting enzyme 2 (ACE2) mRNA in SARS-CoV-2 infection with different infection status and at different stages during infection, we used RT-qP CR to measure the expression of ACE2 mRNA. Measurements were analyzed by two-way repeated measures analysis of variance (RMANOVA). Expression of ACE2 mRNA was downregulated in initial stages of SARS-CoV-2 infection both in the asymptomatic infection (ASY) group and the confirmed cases (CON) group (t=-8.0845, P < 0.0001; t=-8.1904, P < 0.0001, respectively). The expression of ACE2 mRNA in the incubation period of CON group was lower compared with the intinal period of ASY group (F = 6.084, p = 0.016, partialη2 = 0.070). Relative expression of ACE2 mRNA was upregulated at the late stage of SARS-CoV-2 infection in the ASY and CON groups (F = 23.489, p = 0.000, partialη2 = 0.225; F = 46.555, p = 0.000, partialη2 = 0.365, respectively). The relative expression of ACE2 mRNA was down-regulated (mean ± SEM:0.69 ± 0.03) after inoculation with SARSCoV- 2 Spike pseudovirus, and there was a statistical difference (one-way t test, mean diffience =-0.31, 95%CI: -0.37˜-0.24, t=-8.1904, P < 0.0001). The expression of ACE2 mRNA is downregulated in the initial stage of SARS-CoV-2 infection, and then upregulated in the late stage of SARS-CoV-2 infection. The lower expression of ACE2 mRNA during the incubation period can lead to clinical symptoms. Downregulation of ACE2 mRNA was related to the interaction between SARS-CoV-2 S protein and ACE2.Communicated by Ramaswamy H. Sarma.


Assuntos
COVID-19 , Humanos , COVID-19/genética , Enzima de Conversão de Angiotensina 2/genética , SARS-CoV-2/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo
4.
China CDC Wkly ; 4(23): 504-508, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35813263

RESUMO

Introduction: Recently, a local cluster epidemic has occurred in Shijiazhuang City, Hebei Province. Failure to promptly identify patients with fever in rural areas was the major reason for this epidemic. Methods: We presented the field evaluation of a new real-time reverse transcription recombinase-aided amplification (RT-RAA) kit incorporating an endogenous internal control in a single-tube format, completed at the Hebei CDC from January 17, 2021 to January 27, 2021. Results: We evaluated the diagnostic performance of RT-RAA assay using automatic extracted RNA of 808 clinical samples. Compared with reverse transcriptase real-time quantitative PCR (qRT-PCR), RT-RAA kit achieved 92.41% sensitivity, 98.78% specificity and a 96.29% coincidence rate, demonstrating an excellent agreement between the RT-RAA assay and qRT-PCR assay. Furthermore, 58 samples were extracted using a manual extraction method within 5 minutes, but only samples with high nucleic acid concentration (cycle threshold value not higher than 32) could be stably detected. Discussion: The RT-RAA is more suitable to meet the needs of rapid, sensitive, and accurate detection in community-level medical institutions.

5.
Mol Biol Cell ; 33(1): ar10, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34705524

RESUMO

Stress fibers (SFs), which are actomyosin structures, reorganize in response to various cues to maintain cellular homeostasis. Currently, the protein components of SFs are only partially identified, limiting our understanding of their responses. Here we isolate SFs from human fibroblasts HFF-1 to determine with proteomic analysis the whole protein components and how they change with replicative senescence (RS), a state where cells decline in the ability to replicate after repeated divisions. We found that at least 135 proteins are associated with SFs, and 63 of them are up-regulated with RS, by which SFs become larger in size. Among them, we focused on eEF2 (eukaryotic translation elongation factor 2) as it exhibited on RS the most significant increase in abundance. We show that eEF2 is critical to the reorganization and stabilization of SFs in senescent fibroblasts. Our findings provide a novel molecular basis for SFs to be reinforced to resist cellular senescence.


Assuntos
Senescência Celular/fisiologia , Fator 2 de Elongação de Peptídeos/metabolismo , Fibras de Estresse/fisiologia , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Linhagem Celular , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Fator 2 de Elongação de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Proteômica/métodos , Fibras de Estresse/metabolismo
6.
Mol Biol Cell ; 32(21): ar28, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34524873

RESUMO

The Rho family of GTPases are inactivated in a cell context-dependent manner by Rho-GTPase-activating proteins (Rho-GAPs), but their signaling mechanisms are poorly understood. Here we demonstrate that ARHGAP4, one of the Rho-GAPs, forms a complex with SEPT2 and SEPT9 via its Rho-GAP domain and SH3 domain to enable both up- and down-modulation of integrin-mediated focal adhesions (FAs). We show that silencing ARHGAP4 and overexpressing its two mutually independent upstream regulators, SEPT2 and SEPT9, all induce reorganization of FAs to newly express Integrin Beta 1 and also enhance both cell migration and invasion. Interestingly, even if these cell migration/invasion-associated phenotypic changes are induced upon perturbations to the complex, it does not necessarily cause enhanced clustering of FAs. Instead, its extent depends on whether the microenvironment contains ligands suitable for the up-regulated Integrin Beta 1. These results provide novel insights into cell migration, invasion, and microenvironment-dependent phenotypic changes regulated by the newly identified complex.


Assuntos
Proteínas Ativadoras de GTPase/metabolismo , Septinas/metabolismo , Adesão Celular/genética , Movimento Celular/genética , Movimento Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo , Adesões Focais/genética , Adesões Focais/fisiologia , Proteínas Ativadoras de GTPase/genética , Células HEK293 , Humanos , Integrinas/metabolismo , Invasividade Neoplásica/genética , Septinas/genética , Transdução de Sinais/genética , Proteína rhoA de Ligação ao GTP/metabolismo
7.
Cell Death Dis ; 12(3): 264, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712565

RESUMO

Super-enhancers or stretch enhancers (SEs) consist of large clusters of active transcription enhancers which promote the expression of critical genes that define cell identity during development and disease. However, the role of many super-enhancers in tumor cells remains unclear. This study aims to explore the function and mechanism of a new super-enhancer in various tumor cells. A new super-enhancer that exists in a variety of tumors named EphA2-Super-enhancer (EphA2-SE) was found using multiple databases and further identified. CRISPR/Cas9-mediated deletion of EphA2-SE results in the significant downregulation of its target gene EphA2. Mechanistically, we revealed that the core active region of EphA2-SE comprises E1 component enhancer, which recruits TCF7L2 and FOSL2 transcription factors to drive the expression of EphA2, induce cell proliferation and metastasis. Bioinformatics analysis of RNA-seq data and functional experiments in vitro illustrated that EphA2-SE deletion inhibited cell growth and metastasis by blocking PI3K/AKT and Wnt/ß-catenin pathway in HeLa, HCT-116 and MCF-7 cells. Overexpression of EphA2 in EphA2-SE-/- clones rescued the effect of EphA2-SE deletion on proliferation and metastasis. Subsequent xenograft animal model revealed that EphA2-SE deletion suppressed tumor proliferation and survival in vivo. Taken together, these findings demonstrate that EphA2-SE plays an oncogenic role and promotes tumor progression in various tumors by recruiting FOSL2 and TCF7L2 to drive the expression of oncogene EphA2.


Assuntos
Elementos Facilitadores Genéticos , Antígeno 2 Relacionado a Fos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Receptor EphA2/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Células A549 , Animais , Movimento Celular , Proliferação de Células , Antígeno 2 Relacionado a Fos/metabolismo , Células HCT116 , Células HeLa , Humanos , Células MCF-7 , Camundongos Nus , Metástase Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor EphA2/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Via de Sinalização Wnt
8.
FASEB J ; 34(6): 8326-8340, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32378260

RESUMO

Epithelial to mesenchymal transition (EMT) is a fundamental biological process that occurs during development and tumorigenesis. The Rho family of GTPases (Rho-family) is a well-characterized regulator of actin cytoskeleton that gives rise to EMT-associated cell activities. Meanwhile, there are in total at least 66 different Rho-GTPase-activating proteins (Rho-GAPs), which, as an upstream regulator, inactivate specific members of the Rho-family in a cell context-dependent manner. However, molecular roles of individual Rho-GAPs are poorly understood, particularly regarding their involvements in EMT. Here, based on comprehensive screening on the whole Rho-GAP family, we identified specific Rho-GAPs that are responsible for the maintenance of epithelial cell phenotypes, suppressing EMT in human mammary epithelial cells. Specifically, we revealed that at least two Rho-GAPs, that is, ARHGAP4 and SH3BP1, critically regulate the cell morphology. Among them, we focused on ARHGAP4 and demonstrated with multidisciplinary approaches that this specific Rho-GAP regulates epithelial/mesenchymal-selective marker expression, cell proliferation, migration, 3D morphogenesis, and focal adhesion/stress fiber-driven physical force generation in a manner reminiscent of the EMT process. Furthermore, we identified Septin9 with proteomic analyses as a negative regulator of ARHGAP4, which promotes the occurrence of EMT by activation of the FAK/Src signaling pathway. These findings shed light on the novel Rho-GAP-associated pathway in the EMT process under development and tumorigenesis.


Assuntos
Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Proteínas Ativadoras de GTPase/metabolismo , Septinas/metabolismo , Citoesqueleto de Actina/metabolismo , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Adesões Focais/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Humanos , Células MCF-7 , Morfogênese/fisiologia , Proteômica/métodos , Transdução de Sinais/fisiologia
9.
BMC Infect Dis ; 19(1): 765, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477045

RESUMO

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an emerging zoonotic infectious disease caused by hantaviruses which circulate worldwide. So far, it was still considered as one of serious public health problems in China. The present study aimed to reveal the stabilities and variations of hantavirus infection in Hebei province located in North China through a long-term retrospective observation. METHODS: The epidemiological data of HFRS cases from all 11 cities of Hebei province since 1981 through 2016 were collected and descriptively analyzed. The rodent densities, species compositions and virus-carrying rates of different regions were collected from six separated rodent surveillance points which set up since 2007. The molecular diversity and phylogenetic relationship of hantaviruses circulating among rodents were analyzed based on partial viral glycoprotein gene. RESULTS: HFRS cases have been reported every year in Hebei province, since the first local case was identified in 1981. The epidemic history can be artificially divided into three phases and a total of 55,507 HFRS cases with 374 deaths were reported during 1981-2016. The gender and occupational factors of susceptible population were invarible throughout, however age of that was gradually aging. The annual outbreak peak always present in spring, while the main epidemic region had gradully altered from south to northeast. Surveillance of rodents revealed that residential rodents significantly possessed higher density and virus-carring rate than field rodents. The house rat, Rattus norvegicus, was the dominant rodent species and Seoul virus S3 sub-genotype which is continued but slightly evolving perhaps to be the sole pathogen for local HFRS cases of Hebei province. CONCLUSIONS: This long-term province-wide surveillance and epidemiological analysis has revealed the stabilities and variations of hantavirus infection in North China. In order to improve current prevention and control strategies of HFRS in China, all surveillance should be continuously enhanced and variations should be paid more attentions.


Assuntos
Infecções por Hantavirus/epidemiologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , Animais , China/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Epidemias/estatística & dados numéricos , Genótipo , Orthohantavírus/classificação , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/virologia , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Filogenia , Dinâmica Populacional , Vigilância da População , Ratos , Estudos Retrospectivos , Roedores/virologia , Fatores de Tempo , Zoonoses/epidemiologia , Zoonoses/virologia
10.
J Med Virol ; 91(3): 337-346, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30133872

RESUMO

Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in China, where approximately 90% of the total human cases in the world are reported. The Hebei province, one of areas with the highest prevalence, has reported HFRS cases every year in the last two decades. This study describes the spatiotemporal patterns of HFRS in the Hebei province from 2001 to 2016, detects the high-risk spatiotemporal clusters of HFRS, and provides valuable information for planning and implementation of local preventive measures. For the purpose of the analysis, HFRS cases recorded during the sixteen years in the Hebei province were aggregated into three temporal periods (2001-2006, 2007-2012, and 2013-2016). Spatiotemporal analyses, including Global spatial autocorrelation analysis and Kulldorff's scan statistical analysis, were applied to analyze te spatiotemporal clusters of HFRS at the county level. The results revealed that the spatial extent of the HFRS epidemic in the Hebei province changed dynamically from 2001 to 2016, which indicated that a comprehensive preventative strategy should be implemented in the northeastern regions of the Hebei province in spring.


Assuntos
Febre Hemorrágica com Síndrome Renal/epidemiologia , Análise Espaço-Temporal , China/epidemiologia , Análise por Conglomerados , Sistemas de Informação Geográfica , Humanos , Incidência , Estações do Ano
11.
BMC Genomics ; 17(1): 1006, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27931183

RESUMO

BACKGROUND: The switch from photosynthetic or predatory to parasitic life strategies by apicomplexans is accompanied with a reductive evolution of genomes and losses of metabolic capabilities. Cryptosporidium is an extreme example of reductive evolution among apicomplexans, with losses of both the mitosome genome and many metabolic pathways. Previous observations on reductive evolution were largely based on comparative studies of various groups of apicomplexans. In this study, we sequenced two divergent Cryptosporidium species and conducted a comparative genomic analysis to infer the reductive evolution of metabolic pathways and differential evolution of invasion-related proteins within the Cryptosporidium lineage. RESULTS: In energy metabolism, Cryptosporidium species differ from each other mostly in mitosome metabolic pathways. Compared with C. parvum and C. hominis, C. andersoni possesses more aerobic metabolism and a conventional electron transport chain, whereas C. ubiquitum has further reductions in ubiquinone and polyisprenoid biosynthesis and has lost both the conventional and alternative electron transport systems. For invasion-associated proteins, similar to C. hominis, a reduction in the number of genes encoding secreted MEDLE and insulinase-like proteins in the subtelomeric regions of chromosomes 5 and 6 was also observed in C. ubiquitum and C. andersoni, whereas mucin-type glycoproteins are highly divergent between the gastric C. andersoni and intestinal Cryptosporidium species. CONCLUSIONS: Results of the study suggest that rapidly evolving mitosome metabolism and secreted invasion-related proteins could be involved in tissue tropism and host specificity in Cryptosporidium spp. The finding of progressive reduction in mitosome metabolism among Cryptosporidium species improves our knowledge of organelle evolution within apicomplexans.


Assuntos
Cryptosporidium/genética , Mitocôndrias/metabolismo , Ciclo do Ácido Cítrico/genética , Mapeamento de Sequências Contíguas , Cryptosporidium/classificação , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético/genética , Evolução Molecular , Genoma , Redes e Vias Metabólicas/genética , Mitocôndrias/genética , Filogenia , Proteínas de Protozoários/metabolismo
12.
J Microbiol ; 54(7): 468-76, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27350612

RESUMO

Cyanobacterial blooms in freshwaters have become one of the most widespread of environmental problems and threaten water resources worldwide. Previous studies on cyanobacteria in Lake Taihu often collected samples from one site (like Meiliang Bay or Zhushan Bay) and focused on the variation in patterns or abundance of Microcystis during the blooming season. However, the distribution of cyanobacteria in Lake Taihu shows differing pattern in various seasons. In this study, water samples were collected monthly for one year at five sites in Lake Taihu with different trophic status and a physicochemical analysis and denaturing gradient gel electrophoresis (DGGE) were conducted. DGGE fingerprint analysis showed that Microcystis (7/35 bands) and Synechococcus (12/35 bands) were the two most dominant genera present during the study period at all five sites. Cyanobium (3/35 bands) was the third most common genus which has seldom been previously reported in Lake Taihu. Redundancy analysis (RDA) indicated that the cyanobacterial community structure was significantly correlated with NO3 (-)-N, CODMn, and NH4 (+)-N in the winter and spring, whereas it was correlated with water temperature in the summer and autumn. Limiting the nutrient input (especially of N and C loading) in Lake Taihu would be a key factor in controlling the growth of different genera of cyanobacteria.


Assuntos
Cianobactérias/isolamento & purificação , Lagos/microbiologia , China , Cianobactérias/classificação , Cianobactérias/genética , Eletroforese em Gel de Gradiente Desnaturante , Ecossistema , Monitoramento Ambiental , Lagos/química , Filogenia , Estações do Ano
13.
BMC Genomics ; 17: 316, 2016 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-27129308

RESUMO

BACKGROUND: Cyclospora cayetanensis is an apicomplexan that causes diarrhea in humans. The investigation of foodborne outbreaks of cyclosporiasis has been hampered by a lack of genetic data and poor understanding of pathogen biology. In this study we sequenced the genome of C. cayetanensis and inferred its metabolism and invasion components based on comparative genomic analysis. RESULTS: The genome organization, metabolic capabilities and potential invasion mechanism of C. cayetanensis are very similar to those of Eimeria tenella. Propanoyl-CoA degradation, GPI anchor biosynthesis, and N-glycosylation are some apparent metabolic differences between C. cayetanensis and E. tenella. Unlike Eimeria spp., there are no active LTR-retrotransposons identified in C. cayetanensis. The similar repertoire of host cell invasion-related proteins possessed by all coccidia suggests that C. cayetanensis has an invasion process similar to the one in T. gondii and E. tenella. However, the significant reduction in the number of identifiable rhoptry protein kinases, phosphatases and serine protease inhibitors indicates that monoxenous coccidia, especially C. cayetanensis, have limited capabilities or use a different system to regulate host cell nuclear activities. C. cayetanensis does not possess any cluster of genes encoding the TA4-type SAG surface antigens seen in E. tenella, and may use a different family of surface antigens in initial host cell interactions. CONCLUSIONS: Our findings indicate that C. cayetanensis possesses coccidia-like metabolism and invasion components but unique surface antigens. Amino acid metabolism and post-translation modifications of proteins are some major differences between C. cayetanensis and other apicomplexans. The whole genome sequence data of C. cayetanensis improve our understanding of the biology and evolution of this major foodborne pathogen and facilitate the development of intervention measures and advanced diagnostic tools.


Assuntos
Antígenos de Protozoários/imunologia , Cyclospora/fisiologia , Metabolismo Energético , Genoma , Genômica , Biomarcadores , Biologia Computacional/métodos , Cyclospora/patogenicidade , Metabolismo Energético/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Filogenia
14.
Parasit Vectors ; 8: 358, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26152563

RESUMO

BACKGROUND: Cyclospora cayetanensis is an important cause for diarrhea in children in developing countries and foodborne outbreaks of cyclosporiasis in industrialized nations. To improve understanding of the basic biology of Cyclospora spp. and development of molecular diagnostic tools and therapeutics, we sequenced the complete apicoplast and mitochondrial genomes of C. cayetanensis. METHODS: The genome of one Chinese C. cayetanensis isolate was sequenced using Roche 454 and Illumina technologies. The assembled genomes of the apicoplast and mitochondrion were retrieved, annotated, and compared with reference genomes for other apicomplexans to infer genome organizations and phylogenetic relationships. Sequence variations in the mitochondrial genome were identified by comparison of two C. cayetanensis nucleotide sequences from this study and a recent publication. RESULTS: The apicoplast and mitochondrial genomes of C. cayetanensis are 34,155 and 6,229 bp in size and code for 65 and 5 genes, respectively. Comparative genomic analysis showed high similarities between C. cayetanensis and Eimeria tenella in both genomes; they have 85.6% and 90.4% nucleotide sequence similarities, respectively, and complete synteny in gene organization. Phylogenetic analysis of the genomic sequences confirmed the genetic similarities between cecum-infecting avian Eimeria spp. and C. cayetanensis. Like in other coccidia, both genomes of C. cayetanensis are transcribed bi-directionally. The apicoplast genome is circular, codes for the complete machinery for protein biosynthesis, and contains two inverted repeats that differ slightly in LSU rRNA gene sequences. In contrast, the mitochondrial genome has a linear concatemer or circular mapping topology. Eight single-nucleotide and one 7-bp multiple-nucleotide variants were detected between the mitochondrial genomes of C. cayetanensis from this and recent studies. CONCLUSIONS: The apicoplast and mitochondrial genomes of C. cayetanensis are highly similar to those of cecum-infecting avian Eimeria spp. in both genome organization and sequences. The availability of sequence data beyond rRNA and heat shock protein genes could facilitate studies of C. cayetanensis biology and development of genotyping tools for investigations of cyclosporiasis outbreaks.


Assuntos
Apicoplastos/genética , Coccidiose/veterinária , Cyclospora/genética , Ciclosporíase/parasitologia , Eimeria/genética , Genoma Mitocondrial , Doenças das Aves Domésticas/parasitologia , Animais , Apicoplastos/química , Sequência de Bases , Galinhas , Coccidiose/parasitologia , Cyclospora/química , DNA de Protozoário/química , DNA de Protozoário/genética , Eimeria/química , Genoma de Protozoário , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Homologia de Sequência do Ácido Nucleico , Perus
15.
J Nanosci Nanotechnol ; 14(4): 3001-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24734724

RESUMO

The novel efficient architecture of photocatalyst is fabricated by incorporating graphene oxide (GO) in quantum dots (QDs) sensitized ZnO nanorods and the photocatalytic properties for methyl orange (MO) degradation are investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis-NIR absorption spectroscopy. The results indicate that the incorporating of grapheme oxide is more favourable for the degradation. The improved photocatalytic properties can take several advantages given that the higher carrier mobility of GO which can reduce the recombination of carriers, and assembled quantum dots which can facilitate the absorption of solar light. The paper provides the clue to design the effective and easy recyclable photocatalyst.

16.
J Nanosci Nanotechnol ; 14(4): 3052-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24734733

RESUMO

ZnO nanoparticles doped with trivalent europium ions (Eu3+) were synthesized by the hydrothermal method. The structural properties of the samples were investigated by the X-ray diffraction (XRD). The results indicated that Eu3+ was incorporated into the lattice of ZnO. Photoluminescence (PL) measurements of ZnO:Eu3+ showed a strong red luminescence emission. Specially, the red emission can be obtained even under the nonresonant excitation of 320 nm, and it is explained by an energy transfer mechanism in which the energy is transferred from ZnO matrix to Eu3+. These results indicate that the ZnO:Eu3+ is the attractive candidate phosphor for the application in phosphor-converted light-emitting diodes (pc-LEDs) as red phosphor. The intensity of Eu3+ PL decreased with the increasing Eu3+ concentration and the concentration quenching mechanism was presented based on non-radiative recombination processes in ZnO and the energy back-transfer from the excited state of Eu3+ to the ZnO host. Moreover, the samples were synthesized under low temperature condition.

17.
Med Sci Monit ; 20: 683-7, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24759493

RESUMO

BACKGROUND: To present the treatment outcome for patients with stenosing tenosynovitis of thumb flexor tendon treated with a small S incision and page turning style of annular ligament partial resection. MATERIAL AND METHODS: During a 2-year period between August 2011 and July 2013, 12 consecutive patients (mean age, 45.8 years) with stenosing tenosynovitis of the thumb flexor tendon were prospectively enrolled into this study. All 12 patients underwent longitudinal S skin incision to expose annular ligament and thumb flexor tendon, and with page turning style of annular ligament partial resection to finish the operation. The average range of motion of metacarpophalangeal thumb joint, Quick disability of arm, shoulder, and hand and Short Musculoskeletal Function Assessment Dysfunction score of arm and hand were primary outcome measures. RESULTS: There were 9 cases of stiff metacarpophalangeal joint of thumb and 3 cases of snapping thumb for stenosing tenosynovitis. At 1-year follow-up, all stenosing tenosynovitis had healed by an average of 4 weeks. The average range of motion of the metacarpophalangeal joint was 37.1° (range, 34-40°). No patients had recurrence, cicatricial contraction, or postoperative infection. The average disability of arm, shoulder, and hand was 0.3 out of 100 (range, 0-1.67), and average Short Musculoskeletal Functional Assessment Dysfunction score of arm and hand was 6.9 out of 40 (range, 0-15.6). All 12 patients stated that they were highly satisfied. CONCLUSIONS: Small S incision and page turning style of annular ligament partial resection for stenosing tenosynovitis of thumb flexor tendon is a safe, simple, and reliable alternative treatment with minimal soft-tissue irritation, good functional results and recovery can be expected.


Assuntos
Papel , Encarceramento do Tendão/cirurgia , Tendões/cirurgia , Polegar/cirurgia , Feminino , Humanos , Ligamentos/cirurgia , Masculino , Pessoa de Meia-Idade
18.
J Environ Sci (China) ; 25(12): 2487-91, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24649681

RESUMO

An efficient photocatalyst was fabricated by assembling quantum dots (QDs) onto one-dimensionally-ordered ZnO nanorods, and the photocatalytic properties for Methyl Orange degradation were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-Vis-NIR absorption spectroscopy and photoluminescence. The results indicate that the catalyst with assembled QDs is more favorable for the degradation than the pristine ZnO nanorods. The QDs with core-shell structure lower the photocatalytic ability due to the higher carrier transport barrier of the ZnS shell layer. Besides its degradation efficiency, the photocatalyst has several advantages given that the one-dimensionally-ordered ZnO nanorods have been grown directly on indium tin oxide substrates. The article provides a new method to design an effective and easily recyclable photocatalyst.


Assuntos
Nanotubos/química , Fotólise , Óxido de Zinco/química , Compostos Azo , Pontos Quânticos
19.
Zhonghua Yi Xue Za Zhi ; 88(24): 1715-8, 2008 Jun 24.
Artigo em Chinês | MEDLINE | ID: mdl-19024546

RESUMO

OBJECTIVE: To investigate the effects of estrogen-deficiency upon the expression of osteoprotegerin (OPG) in alveolar bone so as to clarify the role of estrogen in alveolar bone metabolism. METHODS: Fifty-three SD rats were randomly divided into 3 groups: OVX group (n=18) undergoing bilateral ovariectomy, OVX + E2 group (n=18), undergoing bilateral ovariectomy and subcutaneous injection of estradiol once 3 days since day 2 after the operation, and sham operation group (n=17) undergoing sham operation. Four weeks after the operation periodontal ligature was conducted and high-sugar diet was fed to establish periodontitis models. Four weeks later the rats were killed. The morphological changes and expression of OPG in alveolar bone were observed by light microscopy and immunohistochemistry. RESULTS: All the rats showed sparseness of bone trabeculae in alveolar bone and osteoclasts and lacuna at the surface of alveolar bone, especially the rate of the group OVX. The A values (absorption of the OPG expression) in the alveolar bone of the OVX groups was 27 854 +/- 5246, significantly lower than those of the sham operation group and OVX + E2 group (38 799 +/- 6228 and 37 146 +/- 6394 respectively, both P < 0.05) without significant difference between the sham operation group and OVX + E2 group (P > 0.05). CONCLUSION: Estrogen deficiency decreases the expression of OPG in alveolar bone, and enhances the absorption of alveolar bone.


Assuntos
Processo Alveolar/metabolismo , Estrogênios/deficiência , Osteoprotegerina/biossíntese , Periodontite/fisiopatologia , Processo Alveolar/efeitos dos fármacos , Animais , Estrogênios/farmacologia , Feminino , Imuno-Histoquímica , Ovariectomia , Ratos , Ratos Sprague-Dawley
20.
Diabetes Res Clin Pract ; 82(1): 132-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18691786

RESUMO

Chronic subclinical inflammation may be involved in the pathogenesis of Type 2 diabetes. We examined whether elevated WBC count, a marker of inflammation, was associated with worsening of glucose tolerance among Chinese population aged 40 years and over. Based on the 75g OGTT, 1016 subjects aged from 40 to 88 years were classified into four groups: NFG/NGT (n=299), isolated IFG (n=213), IGT (n=213) and Type 2 diabetes (n=291). We compared the WBC count among the four groups and investigated relevant variables associated significantly with the WBC count. The IGT and Type 2 diabetes groups had a significantly higher WBC count than the NFG/NGT and isolated IFG groups. By stepwise regression analyses, we found that waist circumference, DBP, total cholesterol, HDL cholesterol and 2-h PG showed an independent association with the WBC count. In the analysis stratified by sex and smoking status, WBC count was independently associated with age and triglycerides in males, whereas it was associated with BMI, SBP, triglycerides and 2-h PG in females. BMI, SBP, triglycerides and 2-h PG showed an independent association with WBC count in subjects who never smoked. We concluded that an increase in WBC count was associated with the deterioration of glucose tolerance. WBC count was associated with lipid metabolism in males and with various components of the metabolic syndrome in females and subjects who never smoked.


Assuntos
Povo Asiático , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Intolerância à Glucose/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Metabolismo dos Carboidratos , China , Diabetes Mellitus Tipo 2/etnologia , Feminino , Intolerância à Glucose/etnologia , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Análise de Regressão
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