Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Transl Med ; 22(1): 428, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711158

RESUMO

BACKGROUND: Lung adenocarcinoma (LUAD) has been a leading cause of cancer-related mortality worldwide. Early intervention can significantly improve prognosis. DNA methylation could occur in the early stage of tumor. Comprehensive understanding the epigenetic landscape of early-stage LUAD is crucial in understanding tumorigenesis. METHODS: Enzymatic methyl sequencing (EM-seq) was performed on 23 tumors and paired normal tissue to reveal distinct epigenetic landscape, for compared with The Cancer Genome Atlas (TCGA) 450K methylation microarray data. Then, an integrative analysis was performed combined with TCGA LUAD RNA-seq data to identify significant differential methylated and expressed genes. Subsequently, the prognostic risk model was constructed and cellular composition was analyzed. RESULTS: Methylome analysis of EM-seq comparing tumor and normal tissues identified 25 million cytosine-phosphate-guanine (CpG) sites and 30,187 differentially methylated regions (DMR) with a greater number of untraditional types. EM-seq identified a significantly higher number of CpG sites and DMRs compared to the 450K microarray. By integrating the differentially methylated genes (DMGs) with LUAD-related differentially expressed genes (DEGs) from the TCGA database, we constructed prognostic model based on six differentially methylated-expressed genes (MEGs) and verified our prognostic model in GSE13213 and GSE42127 dataset. Finally, cell deconvolution based on the in-house EM-seq methylation profile was used to estimate cellular composition of early-stage LUAD. CONCLUSIONS: This study firstly delves into novel pattern of epigenomic DNA methylation and provides a multidimensional analysis of the role of DNA methylation revealed by EM-seq in early-stage LUAD, providing distinctive insights into its potential epigenetic mechanisms.


Assuntos
Adenocarcinoma de Pulmão , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , Metilação de DNA/genética , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Prognóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Perfilação da Expressão Gênica , Ilhas de CpG/genética , Feminino , Estadiamento de Neoplasias , Masculino , Pessoa de Meia-Idade , Genoma Humano , Idoso
2.
Biomacromolecules ; 23(3): 779-788, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35238555

RESUMO

The gradually depleting fossil resources and the biosafety of bisphenol A have always restricted the green development of the traditional epoxy resin field. In this Article, biomass macromolecule lignin sulfonates are selected as the raw material instead of traditional bisphenol A to prepare lignin-based epoxy resin adhesives. Lignin sulfonates are chemically modified and combined with a cross-linking agent to form lignin-based epoxy resin adhesives with double-interpenetrating-network structures. The resulting lignin-based epoxy adhesive exhibits a maximum tensile shear strength of 11.29 MPa, which is 213% higher than the strength before chemical modification. The tensile shear strength of the adhesive is still 10.13 MPa after 12 h of immersion in water (20 °C), and its tensile shear strength is 9.30 MPa after 12 h of immersion in boiling water (100 °C). The high-temperature and high-humidity environment has no significant effect on the properties of the resulting lignin-based epoxy adhesive.


Assuntos
Adesivos , Resinas Epóxi , Adesivos/química , Resinas Epóxi/química , Ambientes Extremos , Lignina/química , Água
3.
Water Res ; 252: 121200, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309061

RESUMO

The metalloids boron and arsenic are ubiquitous and difficult to remove during water treatment. As chemical pretreatment using strong base and oxidants can increase their rejection during membrane-based nanofiltration (NF), we examined a nature-based pretreatment approach using benthic photosynthetic processes inherent in a unique type of constructed wetland to assess whether analogous gains can be achieved without the need for exogenous chemical dosing. During peak photosynthesis, the pH of the overlying clear water column above a photosynthetic microbial mat (biomat) that naturally colonizes shallow, open water constructed wetlands climbs from circumneutral to approximately 10. This biological increase in pH was reproduced in a laboratory bioreactor and resulted in analogous increases in NF rejection of boron and arsenic that is comparable to chemical dosing. Rejection across the studied pH range was captured using a monoprotic speciation model. In addition to this mechanism, the biomat accelerated the oxidation of introduced arsenite through a combination of abiotic and biotic reactions. This resulted in increases in introduced arsenite rejection that eclipsed those achieved solely by pH. Capital, operation, and maintenance costs were used to benchmark the integration of this constructed wetland against chemical dosing for water pretreatment, manifesting long-term (sub-decadal) economic benefits for the wetland-based strategy in addition to social and environmental benefits. These results suggest that the integration of nature-based pretreatment approaches can increase the sustainability of membrane-based and potentially other engineered treatment approaches for challenging water contaminants.


Assuntos
Arsênio , Arsenitos , Poluentes Químicos da Água , Arsênio/análise , Boro , Áreas Alagadas , Fotossíntese , Poluentes Químicos da Água/análise
4.
J Chem Theory Comput ; 19(22): 8032-8052, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37924295

RESUMO

In the noisy intermediate-scale quantum era, ab initio computation of electronic structure problems has become one of the major benchmarks for identifying the boundary between classical and quantum computational power. Basis sets play a key role in the electronic structure methods implemented on both classical and quantum devices. To investigate the consequences of single-particle basis sets, we propose a framework for more customizable basis set generation and optimization. This framework allows composite basis sets to go beyond typical basis set frameworks, such as atomic basis sets, by introducing the concept of mixed-contracted Gaussian-type orbitals. These basis set generations set the stage for more flexible variational optimization of basis set parameters. To realize this framework, we have developed an open-source software package named "Quiqbox" in the Julia programming language. We demonstrate various examples of using Quiqbox for basis set optimization and generation, ranging from optimizing atomic basis sets on the Hartree-Fock level, preparing the initial state for variational quantum eigensolver computation, and constructing basis sets with completely delocalized orbitals. We also include various benchmarks of Quiqbox for basis set optimization and ab initial electronic structure computation.

5.
MethodsX ; 10: 102074, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36865651

RESUMO

Shallow, unit process open water wetlands harbor a benthic microbial mat capable of removing nutrients, pathogens, and pharmaceuticals at rates that rival or exceed those of more traditional systems. A deeper understanding of the treatment capabilities of this non-vegetated, nature-based system is currently hampered by experimentation limited to demonstration-scale field systems and static lab-based microcosms that integrate field-derived materials. This limits fundamental mechanistic knowledge, extrapolation to contaminants and concentrations not present at current field sites, operational optimization, and integration into holistic water treatment trains. Hence, we have developed stable, scalable, and tunable laboratory reactor analogs that offer the capability to manipulate variables such as influent rates, aqueous geochemistry, light duration, and light intensity gradations within a controlled laboratory environment. The design is composed of an experimentally adaptable set of parallel flow-through reactors and controls that can contain field-harvested photosynthetic microbial mats ("biomat") and could be adapted for analogous photosynthetically active sediments or microbial mats. The reactor system is contained within a framed laboratory cart that integrates programable LED photosynthetic spectrum lights. Peristaltic pumps are used to introduce specified growth media, environmentally derived, or synthetic waters at a constant rate, while a gravity-fed drain on the opposite end allows steady-state or temporally variable effluent to be monitored, collected, and analyzed. The design allows for dynamic customization based on experimental needs without confounding environmental pressures and can be easily adapted to study analogous aquatic, photosynthetically driven systems, particularly where biological processes are contained within benthos. The diel cycles of pH and dissolved oxygen (DO) are used as geochemical benchmarks for the interplay of photosynthetic and heterotrophic respiration and likeness to field systems. Unlike static microcosms, this flow-through system remains viable (based on pH and DO fluctuations) and has at present been maintained for more than a year with original field-based materials.•Lab-scale flow-through reactors enable controlled and accessible exploration of shallow, open water constructed wetland function and applications.•The footprint and operating parameters minimize resources and hazardous waste while allowing for hypothesis-driven experiments.•A parallel negative control reactor quantifies and minimizes experimental artifacts.

6.
Sci Total Environ ; 898: 165492, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37453708

RESUMO

Artisanal and small-scale gold mining (ASGM) is the leading global source of anthropogenic mercury (Hg) release to the environment. Top-down mercury reduction efforts have had limited results, but a bottom-up embrace of cyanide (CN) processing could eventually displace mercury amalgamation for gold recovery. However, ASGM transitions to cyanidation nearly always include an overlap phase, with mercury amalgamation then cyanidation being used sequentially. This paper uses a transdisciplinary approach that combines natural and social sciences to develop a holistic picture of why mercury and cyanide converge in gold processing and potential impacts that may be worse than either practice in isolation. We show that socio-economic factors drive the comingling of mercury and cyanide practices in ASGM as much or more so than technical factors. The resultant Hg-CN complexes have been implicated in increasing the mobility of mercury, compared to elemental mercury used in Hg-only processing. To support future inquiry, we identify key knowledge gaps including the role of Hg-CN complexes in mercury oxidation, transport, and fate, and possible links to mercury methylation. The global extent and increase of mercury and cyanide processing in ASGM underscores the importance of further research. The immediacy of the problem also demands interim policy responses while research advances, though ultimately, the well-documented struggles of mercury reduction efforts in ASGM temper optimism about policy responses to the mercury-cyanide transition.

7.
J Healthc Eng ; 2022: 7496785, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463658

RESUMO

Background: The tissues and organs of premature infants are immature and easily damaged by external adverse factors, leading to functional development disorders and abnormalities. Besides, the incidence of premature babies in various countries has an increasing trend, with the incidence rate exceeding 10%. Objective: This study aims to investigate the neurodevelopment and the incidence of various developmental delays, cerebral palsy, autism spectrum disorder, and audio-visual impairment in premature infants under 34 weeks of gestation from birth to 2 years of age, so as to provide the basis for early intervention of premature infants in the clinic. Methods: A cohort of premature infants was established using 263 premature infants with a gestational age of 28-33 + 6 weeks who were born alive from March 1, 2018, to February 28, 2019, in four tertiary hospitals in Shenzhen. In addition, 263 full-term infants of the same sex who were born in the same period in the four hospitals were randomly selected and paired in a ratio of 1 : 1 as the control group. The subjects were assessed for neurodevelopment using the Gesell test scale at 6, 12, 18, and 24 months after birth (premature infants were corrected for months). We calculated the neurodevelopmental indicators of children in each month of age and the incidence of various developmental delays, cerebral palsy, autism spectrum disorder, and audio-visual impairment in the two groups. Results: The results of this study showed that the cohort of premature infants with birth gestational age less than 34 weeks had higher adaptive, fine motor, and personal-social energy domain development quotient (DQ) values from the corrected gestational age of 6 months to the corrected gestational age of 24 months after birth compared with the full-term cohort. And it also achieved catch-up growth in neurological development, but the detection rates of neurodevelopmental abnormalities at the corrected gestational age of 12 and 24 months were higher than those in the full-term cohort. Conclusion: It is important to reduce the disability rate and degree of premature infants by strengthening the systematic management, early promotion and supervision, as well as early intervention for preterm infants with developmental abnormalities who were born at gestational age less than 34 weeks after birth.


Assuntos
Transtorno do Espectro Autista , Paralisia Cerebral , Transtorno do Espectro Autista/epidemiologia , Coorte de Nascimento , Paralisia Cerebral/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Transtornos da Visão
8.
Poult Sci ; 101(12): 102169, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36201879

RESUMO

Transforming growth factor beta receptor Ⅱ (TGFBR2), a core member of the transforming growth factor-ß (TGF-ß) signaling pathway. To date, chicken TGFBR2 (cTGFBR2) genomic structure has not been fully explored. Here, the complete sequences of cTGFBR2 transcript isoforms were determined by 5' and 3' rapid amplification of cDNA ends (5' & 3' RACE) and reverse transcription polymerase chain reaction (RT-PCR); the tissue expression profiling of cTGFBR2 transcript isoforms was performed using quantitative real-time polymerase chain reaction (qRT-PCR). The results showed that cTGFBR2 gene produced 3 transcript isoforms though alternative transcription initiation, splicing, and polyadenylation, which were designated as cTGFBR2-1, cTGFBR2-2, and cTGFBR2-3, respectively. These 3 cTGFBR2 transcript isoforms encoded 3 protein isoforms: cTGFBR2-1, cTGFBR2-2, and cTGFBR2-3. Duplication analysis revealed that, unlike other animal species, cTGFBR2 gene harbored a 5.5-kb intragenic tandem duplication. Tissue expression profiling in the 4-wk-old Arbor Acres (AA) broiler chickens showed that cTGFBR2-1 was ubiquitously expressed, with high expression in abdominal fat, subcutaneous fat, lung, gizzard, and muscle; cTGFBR2-2 was highly expressed in heart, kidney, gizzard, and muscle; cTGFBR2-3 was weakly expressed in all the tested chicken tissues. Tissue expression profiling in the 7-wk-old broiler chickens of the fat and lean lines of Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) showed that cTGFBR2-1 was significantly differentially expressed in all the tested tissues except heart, cTGFBR2-2 was significantly differentially expressed in all the tested tissues except subcutaneous fat and liver, and cTGFBR2-3 was significantly differentially expressed in all the tested tissues between the lean and fat lines. Intriguingly, in the fat line, the 3 cTGFBR2 transcript isoforms were expressed to varying degrees in all the 3 tested fat tissues, while in the lean line, only cTGFBR2-1 was expressed in all the 3 tested fat tissues. This is the first report of intragenic tandem duplication within TGFBR2 gene. Our findings pave the way for further studies on the functions and regulation of cTGFBR2 gene.


Assuntos
Gordura Abdominal , Galinhas , Animais , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Gordura Abdominal/metabolismo , Isoformas de Proteínas/metabolismo , Genômica
9.
Am J Health Syst Pharm ; 79(4): 283-289, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34746953

RESUMO

PURPOSE: The Institute for Safe Medication Practices classifies subcutaneous insulin as a high-risk medication. Concentrated U-500 insulin carries additional risks in comparison to conventional U-100 insulin, as the 5-fold more concentrated nature of this product, limitations to insulin pen dosing, and various devices for dose measurement may lead to miscommunication of patient-reported doses, resulting in downstream errors in ordering, verification, or administration. We describe a multifaceted approach to leveraging technical tools within the electronic health record (EHR) for U-500 insulin use. SUMMARY: At Cleveland Clinic, the U-500 insulin use process evolved in a number of phases using EHR tools. Phase 1 included new clinical decision support and documentation tools during order entry, including a customized alert that fired during order entry recommending that the prescriber order a consult with endocrinology and requiring the prescriber to provide the patient's home insulin measuring device and the source of the patient's reported home dose. In order verification, a customized alert fired directing the pharmacist to contact the patient or patient's nurse and validate the information provided by the prescriber. Phase 2 involved transitioning dispensing of patient-specific doses from tuberculin syringes to U-500 insulin syringes. Phase 3 transitioned to use of U-500 insulin pens and included automatic dose rounding of ordered doses down to the nearest 5 units, and an additional customized pharmacist alert intended for cost conservation was added to fire if the patient had a recent administration of U-500 insulin documented, directing the pharmacist to determine whether the nurse needed a new pen dispensed. CONCLUSION: Cleveland Clinic successfully implemented customized tools and processes within the EHR pertaining to the prescribing, verification, dispensing, and administration of U-500 insulin.


Assuntos
Registros Eletrônicos de Saúde , Insulina , Humanos , Pacientes Internados , Sistemas de Infusão de Insulina , Farmacêuticos
10.
Biosci Biotechnol Biochem ; 75(1): 54-61, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21228487

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that play important roles in a variety of biological processes. Studies of miRNAs in mammals suggest that many are involved in lipid metabolism and adipocyte differentiation, but little is known about miRNA expression profiles during chicken adipogenesis. In this study, the Solexa sequencing approach was used to sequence a small RNA library prepared from Arbor Acres broiler pre-adipocytes, and more than 106 short sequence reads were obtained. From these, 159 known chicken miRNAs and 63 novel miRNAs were identified using a bioinformatics approach. Fifty-nine of these miRNA genes were further organized into 27 compact miRNA genomic clusters, and 34 new chicken mirtrons were also discovered, among which there were 27 mirtron candidates. These findings should serve as a foundation for future research on the functional roles of miRNAs in chicken adipocyte differentiation.


Assuntos
Adipócitos/citologia , Galinhas/genética , MicroRNAs/genética , Análise de Sequência de DNA/métodos , Células-Tronco/metabolismo , Animais , Sequência de Bases , Análise por Conglomerados , Perfilação da Expressão Gênica
11.
Nat Cell Biol ; 21(5): 651-661, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31036937

RESUMO

A single genome gives rise to diverse tissues through complex epigenomic mechanisms, including N6-methyladenosine (m6A), a widespread RNA modification that is implicated in many biological processes. Here, to explore the global landscape of m6A in human tissues, we generated 21 whole-transcriptome m6A methylomes across major fetal tissues using m6A sequencing. These data reveal dynamic m6A methylation, identify large numbers of tissue differential m6A modifications and indicate that m6A is positively correlated with gene expression homeostasis. We also report m6A methylomes of long intergenic non-coding RNA (lincRNA), finding that enhancer lincRNAs are enriched for m6A. Tissue m6A regions are often enriched for single nucleotide polymorphisms that are associated with the expression of quantitative traits and complex traits including common diseases, which may potentially affect m6A modifications. Finally, we find that m6A modifications preferentially occupy genes with CpG-rich promoters, features of which regulate RNA transcript m6A. Our data indicate that m6A is widely regulated by human genetic variation and promoters, suggesting a broad involvement of m6A in human development and disease.


Assuntos
Adenosina/análogos & derivados , Elementos Facilitadores Genéticos , Desenvolvimento Fetal/genética , Feto , Adenosina/genética , Epigenômica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Metilação , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Transcriptoma/genética
12.
Poult Sci ; 96(1): 200-210, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27587730

RESUMO

Gga-miR-21 is abundantly expressed in chicken pre-adipocytes, but its role is unclear. The present study investigated the role of gga-miR-21 in chicken pre-adipocyte proliferation. Cell proliferation assay and gene expression analysis of proliferating cell nuclear antigen (PCNA) showed that the gga-miR-21 mimic inhibited pre-adipocyte proliferation. In contrast, the gga-miR-21 inhibitor enhanced pre-adipocyte proliferation. The subsequent investigation identified Kruppel-like factor 5 (KLF5) mRNA as a target of gga-miR-21. The gga-miR-21 mimic inhibited KLF5 3'UTR reporter activity and decreased endogenous KLF5 expression in primary pre-adipocytes. KLF5 knockdown using RNAi had a similar effect to that of the gga-miR-21 mimic on cell proliferation. The promoting effect of the gga-miR-21 inhibitor on pre-adipocyte proliferation was partially attenuated by KLF5 knockdown. Taken together, our results demonstrated that miR-21 inhibits chicken pre-adipocyte proliferation, at least in part, by targeting KLF5.


Assuntos
Adipócitos/citologia , Proteínas Aviárias/genética , Galinhas/fisiologia , Fatores de Transcrição Kruppel-Like/genética , MicroRNAs/metabolismo , Animais , Proteínas Aviárias/metabolismo , Sequência de Bases , Proliferação de Células , Galinhas/genética , Regulação da Expressão Gênica , Fatores de Transcrição Kruppel-Like/metabolismo , MicroRNAs/genética
13.
PLoS One ; 10(2): e0117843, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25675096

RESUMO

Through posttranscriptional gene regulation, microRNA (miRNA) is linked to a wide variety of biological processes, including adipogenesis and lipid metabolism. Although miRNAs in mammalian adipogenesis have been worked on extensively, their study in chicken adipogenesis is still very limited. To find miRNAs potentially important for chicken preadipocyte development, we compared the preadipocyte miRNA expression profiles in two broiler lines divergently selected for abdominal fat content, by sequencing two small RNA libraries constructed for primary preadipocytes isolated from abdominal adipose tissues. After bioinformatics analyses, from chicken miRNAs deposited in miRBase 20.0, we identified 225 miRNAs to be expressed in preadipocytes, 185 in the lean line and 200 in the fat line (derived from 208 and 203 miRNA precursors, respectively), which corresponds to 114 miRNA families. The let-7 family miRNAs were the most abundant. Furthermore, we validated the sequencing results of 15 known miRNAs by qRT-PCR, and confirmed that the expression levels of most miRNAs correlated well with those of Solexa sequencing. A total of 33 miRNAs was significantly differentially expressed between the two chicken lines (P<0.05). Gene ontology analysis revealed that they could target genes enriched in the regulation of gene transcription and chromatin function, response to insulin stimulation, and IGF-1 signaling pathways, which could have important roles in preadipocyte development. Therefore, a valuable information and resource of miRNAs on chicken adipogenesis were provided in this study. Future functional investigations on these miRNAs could help explore related genes and molecular networks fundamental to preadipocyte development.


Assuntos
Gordura Abdominal/citologia , Gordura Abdominal/metabolismo , Adipogenia/genética , Galinhas/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/genética , Animais , Biologia Computacional/métodos , Regulação da Expressão Gênica , Genoma , Genômica , Anotação de Sequência Molecular , Reprodutibilidade dos Testes
14.
PLoS One ; 8(1): e54238, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23365653

RESUMO

To explore the epidemic history of HIV-1 CRF01_AE in China, 408 fragments of gag gene sequences of CRF01_AE sampled in 2002-2010 were determined from different geographical regions and risk populations in China. Phylogenetic analysis indicates that the CRF01_AE sequences can be grouped into four clusters, suggesting that at least four genetically independent CRF01_AE descendants are circulating in China, of which two were closely related to the isolates from Thailand and Vietnam. Cluster 1 has the most extensive distribution in China. In North China, cluster 1 and cluster 4 were mainly transmitted through homosexuality.The real substance of the recent HIV-1 epidemic in men who have sex with men(MSM) of North China is a rapid spread of CRF01_AE, or rather two distinctive natives CRF01_AE.The time of the most recent common ancestor (tMRCA) of four CRF01_AE clusters ranged from the years 1990.9 to 2003.8 in different regions of China. This is the first phylogenetic and temporal dynamics study of HIV-1 CRF01_AE in China.


Assuntos
Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Família Multigênica , Produtos do Gene gag do Vírus da Imunodeficiência Humana/classificação , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Adulto , Idoso , China/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/isolamento & purificação , Homossexualidade Masculina , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Fatores de Risco , Comportamento Sexual , Fatores de Tempo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/isolamento & purificação
15.
AIDS Res Hum Retroviruses ; 28(1): 119-23, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21568759

RESUMO

The purpose of this study was to investigate the genetic diversity of HIV-1 circulating in Beijing and its molecular epidemiological linkages with regard to risk factors of viral transmission. HIV-1 from plasma samples of 280 diagnosed individuals (2006-2007) was characterized. The gene fragments of gag, pol, and env from the infected plasma samples were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), sequenced, and phylogenetically analyzed. From the 280 plasma samples analyzed, a total of 496 sequences were successfully amplified from the gag, pol, and env genes. Nine HIV-1 group M subtypes or CRF including A1, B, B', C, CRF01_AE, CRF02_AG, CRF06_cpx, CRF07_BC, and CRF08_BC, and six new B'/C recombinants were identified. CRF07_BC was found to be the most dominant subtype (32.5%) followed by CRF01_AE (25.0%), B (20.0%), and B' (15.7%). The data from this study indicate the existence of multiple HIV-1 subtypes or CRFs in Beijing and may be proven useful in the development of vaccine candidates in the future.


Assuntos
Povo Asiático , Soropositividade para HIV/genética , HIV-1/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Adolescente , Adulto , Idoso , Povo Asiático/estatística & dados numéricos , China/epidemiologia , Análise por Conglomerados , Feminino , Variação Genética , Soropositividade para HIV/epidemiologia , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inquéritos e Questionários , Adulto Jovem
16.
AIDS Res Hum Retroviruses ; 28(4): 418-23, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21830915

RESUMO

To investigate the prevalence of HIV-1 genotypic mutations for drug resistance among patients in Beijing, blood samples from 145 newly confirmed (2006-2007), treatment-naive HIV-1-infected individuals were analyzed. Seven subtypes or CRF were subsequently determined and scored by the Stanford HIV Drug Resistance algorithm: CRF01_AE HIV-1 (27.6%), subtype B' (24.1%), CRF07_BC (21.4%), subtype B (20.7%), CRF08_BC (3.4%), subtype C (2.1%), and CRF06_cpx (0.7%). Eleven of the 145 subjects studied were found to harbor the strains resistant to either protease inhibitors (PIs) (3.4%), or nucleoside reverse transcriptase inhibitors (NRTIs) (2.1%), or nonnucleoside reverse transcriptase inhibitors (NNRTIs) (3.4%). Although the prevalence of drug resistance was relatively low among the treatment-naive HIV-1 patients in Beijing in comparison to those in industrialized countries, we will continue monitoring newly infected subjects for any potential alteration of the prevalence pattern to ensure the success of the ongoing scale-up of antiretroviral treatment.


Assuntos
Farmacorresistência Viral/genética , Soropositividade para HIV/epidemiologia , HIV-1/efeitos dos fármacos , Mutação , Adulto , China/epidemiologia , Farmacorresistência Viral/efeitos dos fármacos , Feminino , Citometria de Fluxo , Variação Genética , Soropositividade para HIV/tratamento farmacológico , Soropositividade para HIV/genética , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Vigilância de Evento Sentinela , Inquéritos e Questionários
17.
Cancer Res ; 72(4): 1013-22, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22232736

RESUMO

Like many solid tumors, sarcomas are heterogeneous and include a small fraction of the so-called side population (SP) cells with stem-like tumor-initiating potential. Here, we report that SP cells from a soft tissue tumor of enigmatic origin termed undifferentiated pleomorphic sarcoma (also known as malignant fibrous histiocytoma or MFH sarcoma) display activation of both the Hedgehog and Notch pathways. Blockade to these pathways in murine xenograft models, this human cancer decreased the proportion of SP cells present and suppressed tumor self-renewal, as illustrated by the striking inability of xenograft tumors subjected to pathway blockade to be serially transplanted to new hosts. In contrast, conventional chemotherapies increased the proportion of SP cells present in tumor xenografts and did not affect their ability to be serially transplanted. SP cells from these tumors displayed an unexpectedly high proliferation rate which was selectively inhibited by Hedgehog and Notch blockade compared with conventional chemotherapies. Together, our findings deepen the concept that Hedgehog and Notch signaling are fundamental drivers of tumor self-renewal, acting in a small population of tumor-initiating cells present in tumors. Furthermore, our results suggest not only novel treatment strategies for deadly recurrent unresectable forms of this soft tumor subtype, but also potential insights into its etiology which has been historically controversial.


Assuntos
Proteínas Hedgehog/metabolismo , Histiocitoma Fibroso Maligno/metabolismo , Histiocitoma Fibroso Maligno/patologia , Receptores Notch/metabolismo , Animais , Proliferação de Células , Transformação Celular Neoplásica , Perfilação da Expressão Gênica , Proteínas Hedgehog/antagonistas & inibidores , Humanos , Camundongos , Camundongos SCID , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptores Notch/antagonistas & inibidores , Transdução de Sinais/fisiologia , Triparanol/farmacologia
18.
Nanotechnology ; 19(39): 395604, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21832600

RESUMO

Monodisperse nanospheres are formed by coordination polymerization tetrakis(4-pyridyl)porphyrin-metal complexes with chloroplatinic acid in aqueous solution. The porphyrin nanospheres and their platinized nanocomposites have potential applications in catalysis and solar energy conversion systems.

19.
Biotechnol Prog ; 23(1): 265-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17269697

RESUMO

The C2C12 cell line is frequently used as a model of skeletal muscle differentiation. In our serum-free defined culture system, differentiation of C2C12 cells into myotubes required surface-bound signals such as substrate-adsorbed vitronectin or laminin. On the basis of this substrate requirement of myotube formation, we developed a photolithography-based method to pattern C2C12 myotubes, where myotubes formed exclusively on vitronectin surface patterns. We have determined that the optimal line width to form single myotubes is approximately 30 mum. To illustrate a possible application of this method, we patterned myotubes on the top of commercial substrate-embedded microelectrodes. In contrast to previous experiments where cell patterning was achieved by selective attachment of the cells to patterned surfaces in a medium that contained all of the factors necessary for differentiation, this study illustrates that surface patterning of a signaling molecule, which is essential for skeletal muscle differentiation in a defined system, can result in the formation of aligned myotubes on the patterns. This technique is being developed for applications in cell biology, tissue engineering, and robotics.


Assuntos
Técnicas de Cultura de Células/métodos , Células Musculares/citologia , Fibras Musculares Esqueléticas/citologia , Engenharia Tecidual/métodos , Vitronectina/administração & dosagem , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Materiais Revestidos Biocompatíveis/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Meios de Cultura Livres de Soro , Camundongos , Células Musculares/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fotografação/métodos , Propriedades de Superfície , Vitronectina/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA