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1.
Entropy (Basel) ; 23(5)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065367

RESUMO

Using a unique data set containing about 15.06 million truck transportation records in five months, we investigate the highway freight transportation diversity of 338 Chinese cities based on the truck transportation probability pij from one city to another. The transportation probabilities are calculated from the radiation model based on the geographic distance and its cost-based version based on the driving distance as the proxy of cost. For each model, we consider both the population and the gross domestic product (GDP), and find quantitatively very similar results. We find that the transportation probabilities have nice power-law tails with the tail exponents close to 0.5 for all the models. The two transportation probabilities in each model fall around the diagonal pij=pji but are often not the same. In addition, the corresponding transportation probabilities calculated from the raw radiation model and the cost-based radiation model also fluctuate around the diagonal pijgeo=pijcost. We calculate four sets of highway truck transportation diversity according to the four sets of transportation probabilities that are found to be close to each other for each city pair. It is found that the population, the gross domestic product, the in-flux, and the out-flux scale as power laws with respect to the transportation diversity in the raw and cost-based radiation models. It implies that a more developed city usually has higher diversity in highway truck transportation, which reflects the fact that a more developed city usually has a more diverse economic structure.

3.
Arch Virol ; 164(5): 1353-1360, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859472

RESUMO

Animal cells have multiple innate effector mechanisms that inhibit viral replication. For the pathogenic retrovirus human immunodeficiency virus 1 (HIV-1), there are widely expressed restriction factors, such as APOBEC3 proteins, tetherin/BST2, SAMHD1 and MX2, as well as TRIM5α. We previously found that the TRIM5α gene clearly affects SIVmac or HIV-2 replication, but the major determinant of the combinatorial effect caused by multiple host restriction factors is still not fully clear. APOBEC3G (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G), a host restriction factor that restricts HIV replication by causing cytosine deamination, can be targeted and degraded by the SIV/HIV-1/HIV-2 accessory protein Vif. Although rhesus macaques are widely used in HIV/AIDS research, little is known regarding the impact of APOBEC3G gene polymorphisms on viral Vif-mediated ubiquitin degradation in Chinese-origin rhesus macaques. In this study, we therefore genotyped APOBEC3G in 35 Chinese rhesus macaques. We identified a novel transcript and 27 APOBEC3G polymorphisms, including 20 non-synonymous variants and 7 synonymous mutation sites, of which 10 were novel. According to the predicted structure of the A3G protein, we predicted that the E88K and G212D mutations, both on the surface of the A3G protein, would have a significant effect on Vif-induced A3G degradation. However, an in vitro overexpression assay showed that these mutations did not influence HIV-2-Vif-mediated degradation of APOBEC3G. Unexpectedly, another polymorphism L71R, conferred resistance to Vif-mediated ubiquitin degradation, strongly suggesting that L71R might play an important role in antiviral defense mechanisms.


Assuntos
Desaminase APOBEC-3G/genética , Desaminase APOBEC-3G/metabolismo , HIV-2/genética , Replicação Viral/genética , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , China , Citosina Desaminase/genética , Células HEK293 , HIV-2/crescimento & desenvolvimento , Humanos , Macaca mulatta , Polimorfismo Genético/genética , Alinhamento de Sequência , Ubiquitinação
4.
Exp Mol Pathol ; 107: 110-117, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30594602

RESUMO

BACKGROUND: Renal cell carcinoma (RCC) is the most common form of kidney cancer. Recent studies reported that Tescalcin was overexpressed in various tumor types. However, the status of Tescalcin protein expression in RCC and its biological function is uncertain. This study was designed to investigate the expression of Tescalcin in human RCC and its biological function. METHODS: shRNA transfection was performed to abrogates the expression of Tescalcin. Quantitative real time PCR and western blotting assays were used to determine mRNA and protein expression levels, respectively. The cell viability was analyzed by MTT and colony formation. Cell flow cytometry was used to assess pHi value and cell apoptosis. Cell invasive and migratory ability was measured with modified Boyden chamber assay. Xenograft model was setup to evaluate tumor growth. RESULTS: Tescalcin was overexpressed in RCC tissues compared with matched normal tissues. It was also overexpressed in RCC cell lines relative that of normal cells. Suppression Tescalcin with specific shRNA resulted in the inhibition of cell proliferation, migration, invasion and apoptosis of RCC cells. Additionally, silencing of Tescalcin also caused the inhibition of the tumor growth in nude mice. Mechanistic study showed that Tescalcin regulated cell proliferation, migration and invasion via NHE1/pHi axis as well as AKT/NF-κB signaling pathway. CONCLUSIONS: These findings demonstrate that atopic expression of Tescalcin facilitates the survival, migration and invasion of RCC cells via NHE1/pHi axis as well as AKT/ NF-κB signaling pathway, providing new perspectives for the future study of Tescalcin as a therapeutic target for RCC.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , NF-kappa B/metabolismo , Trocador 1 de Sódio-Hidrogênio/metabolismo , Animais , Proliferação de Células/fisiologia , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/fisiologia , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica/fisiopatologia , Transdução de Sinais/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-28787639

RESUMO

The adverse effects of hypoxia are confined to biochemical, physiological, developmental and behavioral processes, especially injury of the brain. In this study, a subset of genes in the brain of Takifugu rubripes were analyzed using digital gene expression (DGE) profiles and next-generation sequencing after acute hypoxia. Among 32 differentially expressed genes, 29 were up-regulated and 3 were down-regulated following hypoxia exposure. Using Gene Ontology analysis, it was found that transcription and translation, metabolism, and the stress response were affected by exposure to hypoxia. KEGG analysis revealed that the neuroactive ligand-receptor interaction pathway was significantly enriched in hypoxia-exposed T. rubripes. To further confirm the differential expression of genes, quantitative real-time PCR was performed to test six candidate genes, with the following five genes exhibiting the same expression patterns as the sequencing results: Proto-oncogene c-fos, Kruppel-like factor 2, immediate early response 2, proopiomelanocortin A and rhodopsin. This work is the first to identify and annotate genes in T. rubripes affected by hypoxia stress. This investigation provides data for understanding the molecular mechanism of fish adaptation to hypoxia and provides a reference for rationally setting dissolved oxygen levels in aquaculture.


Assuntos
Encéfalo/metabolismo , Proteínas de Peixes/genética , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Takifugu/genética , Transcriptoma/genética , Animais , Química Encefálica/genética , Proteínas de Peixes/análise , Proteínas de Peixes/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Takifugu/metabolismo
6.
Pak J Med Sci ; 32(4): 857-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27648028

RESUMO

OBJECTIVE: The purpose of this study focused on a number of factors that have been implicated in calcaneal complications and find the incidence of wound complications. METHODS: This was a retrospective study. A total of 162 patients (176 feet) who underwent calcaneal fractures between 2007 and 2012 were included. The patient's personal details, age, time from injury to surgery, cause of injury, type of fracture, operative details, operating and tourniquet times were collected from hospital computers and paper records. Evidence of complications including wound infection, wound necrosis, pain, malunion, nonunion, impingement, loss of fixation, ect were studied. RESULTS: Forty-seven of one hundred and seventy-six fractures (26.704%) had complications, wound infection was noted in seven fractures (3.977%), twelve fractures developed necrosis (6.818%), 14 fractures (7.955%) developed pain. Malunion was found in five fractures (2.841%), nonunion in two fractures (1.136%) and loss of fixation in four fractures (2.272%). Three neurologic injury was also seen in our study (1.705%). Operating time, time from injury to surgery and type of fracture had some association with complications in operative fixation of calcaneal fractures, which showed a statistically significant improvement (P=0.000, 0.031, 0.020, respectively), but there were no evidence that age and tourniquet time affect the incidence of complication after calcaneal fracture surgery (P=0.119, 0.682, respectively). CONCLUSIONS: Despite developments in the surgical treatment of calcaneal fracture, wound complications still remain inevitable. Advanced imaging techniques, less invasive surgical procedures, wealth of anatomical knowledge, surgical experience and better postoperative care should be ensured.

7.
Asian Pac J Cancer Prev ; 16(8): 3267-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25921130

RESUMO

PURPOSE: To retrospective assess the potential predictors for relapse and create an effective clinical mode for surveillance after orchidectomy in clinical stage I non-seminomatous germ cell testicular tumors (CSI-NSGCTs). MATERIALS AND METHODS: We analyzed data for CSI-NSGCTs patients with non-lymphatic vascular invasion, %ECa < 50% (percentage of embryonal carcinoma < 50%), and negative or declining tumor markers to their half-life following orchidectomy (defined as low-risk patients); these patients were recruited from four Chinese centers between January 1999 and October 2013. Patients were divided into active surveillance group and retroperitoneal lymph node dissection (RPLND) group according to different therapeutic methods after radical orchidectomy was performed. The disease-free survival rates (DFSR) and overall survival rates (OSR) of the two groups were compared by Kaplan-Meier analysis. RESULTS: A total of 121 patients with CSI-NSGCT were collected from four centers, and 81 low-risk patients, including 54 with active surveillance and 27 with RPLND, were enrolled at last. The median follow-up duration was 66.2 (range 6-164) months in the RPLND group and 65.9 (range 8-179) months in the surveillance group. OSR was 100% in active surveillance and RPLND groups, and DFSR was 89.8% and 87.0%, respectively. No significant difference was observed between these two groups (X2=0.108, P=0.743). No significant difference was observed between the patients with a low percentage of embryonal carcinoma (<50%) and those without embryonal carcinoma (87.0% and 91.9%, X2=0.154, P=0.645). No treatment-related complications were observed in the active surveillance group whereas minor and major complications were observed in 13.0% and 26.1% of the RPLND group, respectively. CONCLUSIONS: Active surveillance resulted in similar DFSR and OSR compared with RPLND in our trial. Patients with low-risk CSI-NSGCTs could benefit from risk-adapted surveillance after these patients were subjected to radical orchidectomy.


Assuntos
Carcinoma Embrionário/cirurgia , Tumor do Seio Endodérmico/cirurgia , Excisão de Linfonodo/métodos , Linfonodos/patologia , Recidiva Local de Neoplasia , Teratoma/cirurgia , Neoplasias Testiculares/cirurgia , Conduta Expectante/métodos , Adolescente , Adulto , Carcinoma Embrionário/patologia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Estudos de Coortes , Intervalo Livre de Doença , Tumor do Seio Endodérmico/patologia , Seguimentos , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Orquiectomia , Espaço Retroperitoneal , Estudos Retrospectivos , Risco , Teratoma/patologia , Neoplasias Testiculares/patologia , Adulto Jovem
8.
Fish Shellfish Immunol ; 44(2): 622-32, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25842179

RESUMO

Mortality (>90%) is a big concern in larval rearing facilities of Pacific cod, Gadus macrocephalus, limiting its culture presently still in the experimental stages. Understanding the immune system development of G. macrocephalus is crucial to optimize the aquaculture of this species, to improve the use of economic resources and to avoid abuse of antibiotics. For the transcriptome analysis, using an Illumina sequencing platform, 61,775,698 raw reads were acquired. After a de novo assembly, 77,561 unigenes were obtained. We have classified functionally these transcripts by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). 27 genes mainly related to hematopoietic or lymphoid organ development and somatic diversification of immune receptors have been reported for the first time in Pacific cod, and 14 Ig heavy chain (µ chain) locuses were assembled using Trinity. Based on our previous achievement, we have chosen Rag1 and Igµ as immune system development biomarkers. Full length cDNA of Rag1 and Igµ as biomarkers were obtained respectively using RACE PCR. Concerning Rag1, the deduced amino acid of Rag1 and protein immunodetection revealed a Rag1 isoform of 69 kDa, significantly different from other fish orthologs, such as Oncorhynchus mykiss (121 kDa). Phylogenetic analysis reveals a unique immune system for the Gadus genre, not exclusive for Atlantic cod, among vertebrates. Meanwhile, full length cDNA of Igµ included an ORF of 1710 bp and the deduced amino acid was composed of a leader peptide, a variable domain, CH1, CH2, Hinge, CH3, CH4 and C-terminus, which was in accordance with most teleost. Absolute quantification PCR revealed that significant expression of Rag1 appeared earlier than Igµ, 61 and 95 dph compared to 95 dph, respectively. Here we report the first transcriptomic analysis of G. macrocephalus as the starting point for genetic research on immune system development towards improving the Pacific cod aquaculture.


Assuntos
Biomarcadores/metabolismo , Gadiformes/genética , Gadiformes/imunologia , Proteínas de Homeodomínio/imunologia , Sistema Imunitário/crescimento & desenvolvimento , Cadeias Pesadas de Imunoglobulinas/imunologia , Transcriptoma/imunologia , Animais , Aquicultura/métodos , Sequência de Bases , Western Blotting , Clonagem Molecular , Primers do DNA/genética , Gadiformes/metabolismo , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Homeodomínio/metabolismo , Cadeias Pesadas de Imunoglobulinas/metabolismo , Anotação de Sequência Molecular , Dados de Sequência Molecular
9.
J Steroid Biochem Mol Biol ; 143: 199-206, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24662324

RESUMO

To obtain evidence of the presence of sex steroid hormones in mollusks, hormone variation in the gonads of the Zhikong scallop Chlamys farreri was analyzed using UPLC-MS/MS. These were found, as expected, with concentrations of estrone (E1), 17beta-estradiol (E2), and testosterone (T) in the testes ranging from not detected (ND) to 0.07 ± 0.10, ND to 3.10 ± 2.00, and ND to 2.67 ± 1.55 ng/g wet weight, respectively. In the ovaries, these hormones ranged from ND to 2.45 ± 1.22, ND to 27.90 ± 4.23, and ND to 2.38 ± 1.56 ng/g ww, respectively. The levels of T in males and E2 in females followed a trend similar to the gonadal-somatic index over the course of the reproductive period. In addition, the gene expression of vitellogenin and calmodulin-2 showed similar patterns to T and E2, while the estrogen receptors and calmodulin-1 did not. These results indicate that sex steroids are present in the scallop and that they may regulate endocrine functions during the reproductive process.


Assuntos
Estradiol/metabolismo , Estrona/metabolismo , Expressão Gênica , Ovário/metabolismo , Pectinidae/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Animais , Calmodulina , Feminino , Técnicas Imunoenzimáticas , Masculino , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Fish Physiol Biochem ; 38(6): 1785-1794, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22763698

RESUMO

A 60-day feeding trial was conducted to determine the effects of palm oil blended with oxidized and non-oxidized fish oil on growth performances, hematology, and non-specific immune response in juvenile Japanese sea bass, Lateolabrax japonicas. Japanese sea bass (1.73 ± 0.01 g) were fed seven experimental diets containing 100 g/kg of dietary lipid in forms of palm oil (10P), fish oil (10F), fish oil blended with palm oil at different ratios, 6:4 (6F4P) and 4:6 (4F6P), oxidized fish oil (10OF), and oxidized fish oil blended with palm oil at different ratios, 6:4 (6OF4P) and 4:6 (4OF6P). After the feeding trial, the following results were illustrated. No significant effects were observed in survival, feed conversion ratio, condition factor, and hematocrit after feeding with experimental diets for 60 days. The relatively higher specific growth rate and hematology were observed in 6F4P. Furthermore, both palm oil and oxidized fish oil acted as a negatively on serum lysozyme activity (P < 0.05). This study suggested that a ration of 6F4P is recommended as an innocuous ratio for Japanese sea bass. Furthermore, according to the present investigation, palm oil seems to have the ability to improve the protein efficiency when added to oxidized fish diets as well as a positive trend to the growth performance (P > 0.05).


Assuntos
Óleos de Peixe/farmacologia , Perciformes/sangue , Perciformes/crescimento & desenvolvimento , Óleos de Plantas/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Óleos de Peixe/química , Oxirredução , Óleo de Palmeira , Perciformes/imunologia , Óleos de Plantas/química
11.
Mol Pharm ; 3(5): 589-600, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17009858

RESUMO

The enhanced permeability and retention of liposomes in solid tumors makes liposomal formulations attractive for the targeting of various antitumor agents. This study explores the binding, orientation, and dynamic properties of a potent topoisomerase I inhibitor, 7-tert-butyldimethylsilyl-10-hydroxycamptothecin (DB-67), and its 20(S)-4-aminobutyrate ester prodrug (DB-67-AB) in DMPC liposomes by molecular dynamics (MD) simulations and experimental studies. MD simulations of an all-atom and fully hydrated liquid-crystalline bilayer (2 x 36 DMPC lipids) containing single molecules of DB-67 and DB-67-AB were conducted for up to 50 ns. Membrane/water partition coefficients for DB-67 and DB-67-AB vs pH were determined by ultracentrifugation. Fluorescence spectra and/or steady-state anisotropies were measured in various solvents and in DMPC liposomes. Kinetics for the reversible DB-67 lactone ring-opening in the presence and absence of DMPC liposomes were determined by HPLC with fluorescence detection. During the entire simulation time both DB-67 and DB-67-AB were located on the bilayer membrane near the polar ester groups of DMPC. The average depth of penetration for DB-67 and DB-67-AB was similar (12.4-13.2 A) with the prodrug's protonated amino group strongly solvated by surface water and lipid phosphate groups. Binding and fluorescence experiments revealed only a modest reduction in the binding affinity upon attachment of the ionized 4-aminobutyrate group onto DB-67. The binding microenvironment polarity resembles that of a polar solvent such as EtOH and DMSO. Kinetics experiments confirmed that DB-67 lactone hydrolysis is inhibited in the presence of DMPC liposomes, consistent with the reduced exposure of its lactone ring to water, as observed in the simulations. Both bound DB-67 and bound DB-67-AB have nonrandom orientations and reduced mobility in the membrane, especially for diffusion normal to the bilayer surface, and rotational relaxation, both of which are > or =2 orders of magnitude slower than in bulk water. MD simulations correctly predicted the high binding affinities for DB-67-AB to DMPC bilayers, protection of bound DB-67 toward lactone hydrolysis, and the lack of a substantial reduction in binding for the 20(S)-4-aminobutyrate prodrug of DB-67.


Assuntos
Camptotecina/análogos & derivados , Simulação por Computador , Dimiristoilfosfatidilcolina/química , Ésteres/química , Compostos de Organossilício/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Ligação Competitiva , Camptotecina/química , Camptotecina/metabolismo , Dimiristoilfosfatidilcolina/metabolismo , Ésteres/metabolismo , Cinética , Lactonas/química , Lactonas/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Conformação Molecular , Estrutura Molecular , Compostos de Organossilício/metabolismo
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 26(5): 651-3, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16762875

RESUMO

OBJECTIVE: To assess the value of magnetic resonance imaging (MRI) in mid- and long-term complication monitoring after liver transplantation. METHODS: Twenty-one recipients receiving orthotropic liver transplantation between Feb 2003 and May 2005 were enrolled in this study. FLASH T(1)-weighted, T(2)-weighted fast spin echo, T(2)-weighted fat suppression, dynamic gadolinium-enhanced, MR cholangiopancreatography (MRCP) and three-dimensional dynamic gadolinium-enhanced FISP MRA images were obtained. RESULTS: Of the 21 patients, bile duct complications were detected in all cases and liver arterial and venous complications in 8 cases. Liver cancer relapse occurred in 5 cases and allograft failure in 4. CONCLUSION: MR imaging allows effective monitoring of mid- and long-term complications of liver transplantation, which provides valuable clues for their clinical treatment.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Doenças dos Ductos Biliares/diagnóstico , Transplante de Fígado/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Adulto , Arteriopatias Oclusivas/etiologia , Doenças dos Ductos Biliares/etiologia , Feminino , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/patologia , Humanos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Radiografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Life Sci ; 72(20): 2243-53, 2003 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-12628444

RESUMO

Cell-based models have been used extensively in screening novel bioactive chemical entities. In this study, seven well-established mammalian cell lines, which have different origins, were utilized to compare their responses to the treatments of three detoxifying enzyme inducers, tert-butylhydroquinone (tBHQ), beta-naphthoflavone (beta-NF), and sulforaphane (SUL), which are potential chemopreventive compounds. The enzymatic activities of glutathione s-transferase (GST), NAD(P)H:quinone oxidoreductase (QR), aldehyde reductase (AR), and glutathione reductase (GR) were measured by kinetics methods using UV-Vis spectroscopy, and analyzed statistically by Student's t-test. Among these mammalian cell lines, the mouse hepatoma Hepa1c1c7 cells were the most robust and sensitive cells, which had higher basal as well as upregulated enzymatic activities. In human cell lines, the prostate LNCaP and hepatic HepG2 cells were also very responsive to the inducers. The results suggested that different cell lines responded differently to individual detoxifying gene inducer, and the selection of appropriate cell line is important for screening potential chemopreventive agents.


Assuntos
Indução Enzimática , Glutationa Transferase/biossíntese , Inativação Metabólica , Oxirredutases/biossíntese , Células Tumorais Cultivadas/enzimologia , Aldeído Redutase/biossíntese , Animais , Anticarcinógenos/farmacologia , Quimioprevenção , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/farmacologia , Feminino , Glutationa Redutase/biossíntese , Humanos , Hidroquinonas/farmacologia , Inativação Metabólica/fisiologia , Isotiocianatos , Masculino , Camundongos , NAD(P)H Desidrogenase (Quinona)/biossíntese , Sulfóxidos , Tiocianatos/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , beta-Naftoflavona/farmacologia
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