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1.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(3): 241-251, 2022 Jun 16.
Artigo em Chinês | MEDLINE | ID: mdl-35896487

RESUMO

OBJECTIVE: To predict the trends for fine-scale spread of Oncomelania hupensis based on supervised machine learning models in Shanghai Municipality, so as to provide insights into precision O. hupensis snail control. METHODS: Based on 2016 O. hupensis snail survey data in Shanghai Municipality and climatic, geographical, vegetation and socioeconomic data relating to O. hupensis snail distribution, seven supervised machine learning models were created to predict the risk of snail spread in Shanghai, including decision tree, random forest, generalized boosted model, support vector machine, naive Bayes, k-nearest neighbor and C5.0. The performance of seven models for predicting snail spread was evaluated with the area under the receiver operating characteristic curve (AUC), F1-score and accuracy, and optimal models were selected to identify the environmental variables affecting snail spread and predict the areas at risk of snail spread in Shanghai Municipality. RESULTS: Seven supervised machine learning models were successfully created to predict the risk of snail spread in Shanghai Municipality, and random forest (AUC = 0.901, F1-score = 0.840, ACC = 0.797) and generalized boosted model (AUC= 0.889, F1-score = 0.869, ACC = 0.835) showed higher predictive performance than other models. Random forest analysis showed that the three most important climatic variables contributing to snail spread in Shanghai included aridity (11.87%), ≥ 0 °C annual accumulated temperature (10.19%), moisture index (10.18%) and average annual precipitation (9.86%), the two most important vegetation variables included the vegetation index of the first quarter (8.30%) and vegetation index of the second quarter (7.69%). Snails were more likely to spread at aridity of < 0.87, ≥ 0 °C annual accumulated temperature of 5 550 to 5 675 °C, moisture index of > 39% and average annual precipitation of > 1 180 mm, and with the vegetation index of the first quarter of > 0.4 and the vegetation index of the first quarter of > 0.6. According to the water resource developments and township administrative maps, the areas at risk of snail spread were mainly predicted in 10 townships/subdistricts, covering the Xipian, Dongpian and Tainan sections of southern Shanghai. CONCLUSIONS: Supervised machine learning models are effective to predict the risk of fine-scale O. hupensis snail spread and identify the environmental determinants relating to snail spread. The areas at risk of O. hupensis snail spread are mainly located in southwestern Songjiang District, northwestern Jinshan District and southeastern Qingpu District of Shanghai Municipality.


Assuntos
Ecossistema , Gastrópodes , Animais , Teorema de Bayes , China/epidemiologia , Aprendizado de Máquina Supervisionado
3.
J Biol Regul Homeost Agents ; 34(3): 467-477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32476381

RESUMO

Ovarian cancer (OC) is one of the most common gynecological malignancies, with the highest mortality rate in women worldwide. LINC00662, a long non-coding RNA (lncRNA), was shown to play a vital role in many malignancies, while little is known about its role in OC. Firstly, our study determined the expression of LINC00662 in OC tissues and cells. Upregulation or downregulation of LINC00662 were performed in OC cells to explore its effects on cell proliferation and glycolysis of OC. The interaction between LINC00662 and miR-375 was verified using luciferase assays and RNA immunoprecipitation. Results showed that LINC00662 was highly expressed in OC tissues and cells, and patients with increased expression of LINC00662 were associated with shorter overall survival. Furthermore, functional assays proved that LINC00662 was essential for OC cell proliferation and glycolysis. Subsequently, our study further revealed that LINC00662 acted as a competitive RNA and it could modulate the expression of HIF-1α through directly binding with miR- 375. Collectively, upregulation of LINC00662 in ovarian cancer tissues is closely correlated to poor survival. LINC00662 might regulate HIF-1α expression via miR-375. These findings suggested that LINC00662 has the potential to be explored as a diagnostic biomarker for OC.


Assuntos
Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/genética , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Ovarianas/genética
4.
Artigo em Chinês | MEDLINE | ID: mdl-33660481

RESUMO

OBJECTIVE: To understand the status of chronic filariasis patients in Jiangxi Province in 2018, so as to provide insights into the follow-up care of the patients. METHODS: In 2018, a case follow-up study was conducted in all registered patients with chronic filariasis in previously endemic areas of Jiangxi Province, and a clue investigation was done for identifying the missing patients. In addition, the data of caring sites for chronic filarisis patients were collected and analyzed in the province. RESULTS: A total of 802 chronic filariasis patients were identified in 56 counties (districts) of Jiangxi Province in 2018. The patients had a male/female ratio of 1∶1, and 85.41% had ages of over 70 years. There were 58.60%, 93.89%, 17.21% and 3.62% of chronic filariasis patients with lymphangitis, lymphedema/elephantiasis, chyluria and hydrocele, respectively. A total of 273 caring sites were assigned in 56 counties (districts) of Jiangxi Province, and 306 caring activities were carried out in 2018. CONCLUSIONS: The number of chronic filariasis patients has significantly decreased in Jiangxi Province; however, the care remains to be intensified for chronic filariasis patients.


Assuntos
Filariose Linfática , Idoso , China/epidemiologia , Estudos Transversais , Filariose Linfática/epidemiologia , Feminino , Seguimentos , Humanos , Masculino
5.
J Fish Biol ; 92(1): 85-93, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29139118

RESUMO

This study was conducted to determine the mechanism by which di-2-ethylhexyl phthalate (DEHP) exposure influences lipid metabolism of juvenile yellow catfish Tachysurus fulvidraco. Fish were exposed to three DEHP concentrations (0, 0·1 and 0·5 mg l-1 DEHP) for 8 weeks. Fatty acid synthase (FAS) activity significantly decreased with increasing DEHP concentrations, the highest value was in the Tween control group, whereas the lowest activities of carnitine palmitoyltransferase (CPT) and lipoprotein lipase (LPL) were in this group. The messenger (m)RNA levels of 6-phospho-gluconate dehydrogenase (6PGD), FAS and acetyl-CoA carboxylase a (ACCa) significantly increased with increasing DEHP concentration, the highest values were in the 0·5 mg l-1 DEHP group. The mRNA level of peroxisome proliferator-activated receptor γ (PPARγ) was lower in Tween control than in fish exposed to 0·1 and 0·5 mg l-1 DEHP. The highest mRNA level of ACCb was in the 0·1 mg l-1 DEHP group. These results indicate that DEHP exposure can disturb lipid metabolism at the enzymatic and mRNA levels in Pelteobagrus fulvidraco.


Assuntos
Peixes-Gato/metabolismo , Dietilexilftalato/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Peixes-Gato/genética , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Fígado/metabolismo , RNA Mensageiro/metabolismo
6.
Eur Rev Med Pharmacol Sci ; 20(22): 4761-4765, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27906425

RESUMO

OBJECTIVE: Investigating the correlation between children's status asthmatics and interstitial lung disease (ILD). PATIENTS AND METHODS: We continuously selected 20 cases of children's status asthmatics combined with ILD (group A), 20 cases of pure status asthmatics (group B), 20 cases of pure ILD (group C) and 20 cases of healthy children (group D). We measured Th1/Th2 by flow cytometry as well as the level of expression of hs-CRP, IL-7 cytokines (TSLP), monocyte chemoattractant protein-1 (MCP-1) and anti-Jo-1 antibody by ELISA method. RESULTS: Th1 and Th1/Th2 of groups A and B were significantly lower than those of group C and D. Th2 was significantly (p<0.05) higher than that of groups C and D. The level of expression of hs-CRP, TSLP, MCP-1 and anti-Jo-1 antibody in the groups A and B were all significantly higher (p<0.05) than those of groups C and D. There were differences of the above index of the comparison between groups A and B, but no difference between groups C and D. CONCLUSIONS: Children's status asthmatics and ILD may correlate with the abnormal expression of Th1/Th2, hs-CRP, TSLP, MCP-1 and anti-Jo-1 antibody.


Assuntos
Asma/imunologia , Doenças Pulmonares Intersticiais/imunologia , Anticorpos Antinucleares , Asma/metabolismo , Quimiocina CCL2 , Criança , Humanos , Doenças Pulmonares Intersticiais/metabolismo
7.
Balkan J Med Genet ; 18(1): 77-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26929909

RESUMO

This study was conducted to describe a prenatal case of congenital hydrocephalus and hemivertebrae with a 6q terminal deletion and to investigate the possible correlation between the genotype and phenotype of the proband. We performed an array-based comparative genomic hybridization (aCGH) analysis on a fetus diagnosed with congenital hydrocephalus and hemivertebrae. The deletion, spanning 10.06 Mb from 6q25.3 to 6qter, was detected in this fetus. The results of aCGH, karyotype and fluorescent in situ hybridization (FISH) analyses in the healthy parents were normal, which confirmed that the proband's copy-number variant (CNV) was de novo. This deleted region encompassed 97 genes, including 28 OMIM genes. We discussed four genes (TBP, PSMB1, QKI and Pacrg) that may be responsible for hydrocephalus while the T gene may have a role in hemivertebra. We speculate that five genes in the 6q terminal deletion region were potentially associated with hemivertebrae and hydrocephalus in the proband.

8.
Genet Mol Res ; 13(1): 283-90, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24535855

RESUMO

Increased disease resistance through improved general immune capacity would be beneficial for the welfare and productivity of farm animals. Classical swine fever (CSF) is a contagious disease in farm animals. The immunoglobulin G (IgG) blocking percentage of CSF virus (CSFV) in serum is an essential diagnostic parameter in veterinary practice. In addition, lysozymes are a part of the innate immune system. To identify quantitative trait loci (QTL) for IgG blocking percentage of CSFV and lysozyme concentration, IgG blocking percentage and lysozyme concentration in serum were measured in a composite pig population before and after challenge with modified live CSF vaccine. Through genome-wide mapping by MQREML analysis and the SOLAR software, several QTL for the lysozyme concentration and the IgG blocking percentage of CSFV were identified, respectively. Within these QTL regions, some known genes were revealed, and some of them may serve as candidate genes in the pig.


Assuntos
Anticorpos Antivirais/genética , Vírus da Febre Suína Clássica/imunologia , Imunoglobulina G/genética , Muramidase/genética , Locos de Características Quantitativas , Imunidade Adaptativa/genética , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Mapeamento Cromossômico , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Muramidase/sangue , Suínos
9.
Anim Genet ; 42(1): 1-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20477803

RESUMO

Increased disease resistance through improved general immune capacity would be beneficial for the welfare and productivity of farm animals. Cytokines are essential diagnostic parameters in veterinary practice. To identify quantitative trait loci (QTL) for cytokine levels in serum in the pig, Interferon-gamma (IFN-γ) and Interleukin 10 (IL-10) levels and the ratio of IFN-γ to IL-10 were measured in a composite pig population, before and after challenge with modified live CSF (classical swine fever) vaccine. Through interval mapping using the variance component approach and the permutation test, 11 QTL (five for IFN-γ, two for IL-10 and four for the ratio of IFN-γ to IL-10) with significance levels of P < 0.10 were identified, of which five were significant at the P < 0.05 level. The most significant QTL (P < 0.01) was found on chromosome 16, with effect on the ratio of IFN-γ to IL-10. Within these QTL regions, a number of known genes were revealed and their potential relationships to the studied traits were discussed. Some of these genes may serve as candidate genes for these traits in swine.


Assuntos
Interferon gama/genética , Interleucina-10/genética , Repetições de Microssatélites , Locos de Características Quantitativas , Sus scrofa/genética , Animais , Feminino , Interferon gama/sangue , Interleucina-10/sangue , Masculino
10.
Mol Biol Rep ; 38(7): 4455-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21140225

RESUMO

Low molecular weight polypeptides 2 (LMP2) and low molecular weight polypeptides 7 (LMP7) are located within the major histocompatibility complex and have been associated with autoimmune disease. In this study, polymorphisms of porcine LMP2 and LMP7 genes were analyzed by PCR-SSCP and DNA sequencing methods. Four SNPs (DQ659151:g.2115T>C; DQ659151:g.4343A>G; DQ872631:g.1232C>G; DQ872631:g.2847C>T) were identified. Four SNPs of genes were analyzed for association with 22 haematological traits in Large White (n = 195), Landrace (n = 84) and Songliao Black (n = 86) pig population. Of all the 22 traits, seven were significant associated with the SNPs of LMP2/LMP7 gene (P < 0.05). They included white blood cell count (WBC) (P = 0.028), neutrophilic granulocyte count (GRAN) (P = 0.037), monocytes percentage (MO%) (P = 0.015), red blood cell (RBC) (P = 0.004), red blood cell volume distribution width (RDW) (P = 0.004), mean platelet volume (MPV) (P = 0.016) and CD4(+)CD8(+)% (P = 0.045). These results suggest LMP2/LMP7 gene should be regarded as molecular marker to estimate animal's immune status for their effects on hematological traits.


Assuntos
Estudos de Associação Genética , Polimorfismo de Nucleotídeo Único/genética , Complexo de Endopeptidases do Proteassoma/genética , Característica Quantitativa Herdável , Sus scrofa/sangue , Sus scrofa/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Cromossomos de Mamíferos/genética , Cisteína Endopeptidases/genética , Frequência do Gene/genética , Genótipo , Análise dos Mínimos Quadrados , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples/genética
11.
Genetika ; 45(12): 1646-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20198976

RESUMO

Polymerase chain reaction (PCR) products of the MSTN gene amplified from sixty sheep of nine Chinese indigenous sheep breeds and one imported sheep breed were sequenced to identify the single-nucleotide polymorphisms (SNPs) in a 378-bp fragment including intron 2 and exon 3 of the MSTN gene. A total of fifteen SNPs (A1937C, T1942G, C1956T, A1972C, A1990G, A2008C, A2011G, C2019T, A2025C, A2027C, T2085G, T2173C, C2198T, C2210T and C2213T) were detected among the sixty sequenced individuals and they were all located in intron 2. Twelve haplotypes were identified from these fifteen SNPs, of which haplotype I (CGTCGCGTCCGCTTT) and VIII (ATCAAAACAATTCCC) were the two major and basic ones with frequencies of 12.25% and 77.80%, respectively. Haplotype VIII was distributed in all sheep breeds and all individuals of the meat or meat-wool type sheep breeds were homozygous with respect to this haplotype. This suggests that haplotype VIII might be related to meat production traits in sheep. Haplotype I was only distributed in the fur, lambskin type and fur-meat type sheep breeds. This suggests that haplotype I may have some relationship with fur traits in sheep.


Assuntos
Cabelo , Miostatina/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas/genética , Ovinos/genética , Animais , China , Haplótipos
12.
J Microsc ; 230(Pt 3): 424-34, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18503669

RESUMO

The gas atmosphere in continuous annealing and galvanizing lines alters both composition and microstructure of the surface and sub-surface of sheet steels. The alloying element enrichments and the oxide morphology on transformation-induced plasticity steel surfaces are strongly influenced by the dew point of the furnace atmosphere and annealing temperature. The formation of a thin oxide film and enrichment of the alloying elements during annealing may result in surface defects on galvanized sheet products. The present contribution reports on the use of microanalysis techniques such as electron backscatter diffraction, glow discharge optical emission spectroscopy and electron probe micro-analysis for the detailed surface analysis of inter-critically annealed transformation-induced plasticity steel such as oxide phase determination, microstructure and microtexture evolutions.


Assuntos
Ligas/química , Compostos Férricos/análise , Microscopia Eletrônica/instrumentação , Óxidos/química , Aço/química , Microscopia Eletrônica/métodos , Oxirredução , Análise Espectral
13.
J Anim Breed Genet ; 123(2): 141-4, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16533369

RESUMO

Polymerase chain reaction (PCR) products of MSTN gene amplified from 35 goats representing 17 Chinese indigenous goat breeds and five imported goat breeds were sequenced to identify the single-nucleotide polymorphisms (SNPs) of a 379-bp fragment including part of intron 2 and exon 3 of MSTN gene. A total of eight SNPs (A1980G, G1981C, A1982G, G1984T, A2121G, T2124C, G2174A and A2246G) were identified among the sequenced goats. The SNPs found are all located in intron 2 except for A2246G, which was a synonymous mutation in exon 3. Four haplotypes were sorted from these eight SNPs, of which, haplotype I (AGAGATGA) and haplotype II (GCGTGTAA) are the two main haplotypes with the frequency of 77.8% and 14.8% respectively. The SNPs found at positions 1980, 1981, 1982, 1984 and 2121 might be linked to inheritance completely.


Assuntos
Cabras/genética , Polimorfismo de Nucleotídeo Único/genética , Fator de Crescimento Transformador beta/genética , Animais , China , Haplótipos , Miostatina , Reação em Cadeia da Polimerase
14.
Antimicrob Agents Chemother ; 44(9): 2319-26, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10952574

RESUMO

BMS-232632 is an azapeptide human immunodeficiency virus (HIV) type 1 (HIV-1) protease inhibitor that displays potent anti-HIV-1 activity (50% effective concentration [EC(50)], 2.6 to 5.3 nM; EC(90), 9 to 15 nM). In vitro passage of HIV-1 RF in the presence of inhibitors showed that BMS-232632 selected for resistant variants more slowly than nelfinavir or ritonavir did. Genotypic and phenotypic analysis of three different HIV strains resistant to BMS-232632 indicated that an N88S substitution in the viral protease appeared first during the selection process in two of the three strains. An I84V change appeared to be an important substitution in the third strain used. Mutations were also observed at the protease cleavage sites following drug selection. The evolution to resistance seemed distinct for each of the three strains used, suggesting multiple pathways to resistance and the importance of the viral genetic background. A cross-resistance study involving five other protease inhibitors indicated that BMS-232632-resistant virus remained sensitive to saquinavir, while it showed various levels (0. 1- to 71-fold decrease in sensitivity)-of cross-resistance to nelfinavir, indinavir, ritonavir, and amprenavir. In reciprocal experiments, the BMS-232632 susceptibility of HIV-1 variants selected in the presence of each of the other HIV-1 protease inhibitors showed that the nelfinavir-, saquinavir-, and amprenavir-resistant strains of HIV-1 remained sensitive to BMS-232632, while indinavir- and ritonavir-resistant viruses displayed six- to ninefold changes in BMS-232632 sensitivity. Taken together, our data suggest that BMS-232632 may be a valuable protease inhibitor for use in combination therapy.


Assuntos
Inibidores da Protease de HIV/farmacologia , Protease de HIV/metabolismo , HIV-1/efeitos dos fármacos , Oligopeptídeos/farmacologia , Piridinas/farmacologia , Sequência de Aminoácidos , Sulfato de Atazanavir , Resistência Microbiana a Medicamentos/fisiologia , Resistência a Múltiplos Medicamentos/fisiologia , Protease de HIV/genética , HIV-1/enzimologia , HIV-1/genética , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mutação , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
15.
Antimicrob Agents Chemother ; 44(8): 2093-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10898681

RESUMO

BMS-232632 is an azapeptide human immunodeficiency virus type 1 (HIV-1) protease (Prt) inhibitor that exhibits potent anti-HIV activity with a 50% effective concentration (EC(50)) of 2.6 to 5.3 nM and an EC(90) of 9 to 15 nM in cell culture. Proof-of-principle studies indicate that BMS-232632 blocks the cleavage of viral precursor proteins in HIV-infected cells, proving that it functions as an HIV Prt inhibitor. Comparative studies showed that BMS-232632 is generally more potent than the five currently approved HIV-1 Prt inhibitors. Furthermore, BMS-232632 is highly selective for HIV-1 Prt and exhibits cytotoxicity only at concentrations 6,500- to 23, 000-fold higher than that required for anti-HIV activity. To assess the potential of this inhibitor when used in combination with other antiretrovirals, BMS-232632 was evaluated for anti-HIV activity in two-drug combination studies. Combinations of BMS-232632 with either stavudine, didanosine, lamivudine, zidovudine, nelfinavir, indinavir, ritonavir, saquinavir, or amprenavir in HIV-infected peripheral blood mononuclear cells yielded additive to moderately synergistic antiviral effects. Importantly, combinations of drug pairs did not result in antagonistic anti-HIV activity or enhanced cytotoxic effects at the highest concentrations used for antiviral evaluation. Our results suggest that BMS-232632 may be an effective HIV-1 inhibitor that may be utilized in a variety of different drug combinations.


Assuntos
Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , Oligopeptídeos/farmacologia , Piridinas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Sulfato de Atazanavir , Proteínas Sanguíneas , Células Cultivadas , Combinação de Medicamentos , Interações Medicamentosas , Produtos do Gene gag/metabolismo , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Precursores de Proteínas/metabolismo
16.
Br J Cancer ; 77(8): 1208-12, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9579824

RESUMO

The ability of tumour necrosis factor alpha (TNF-alpha), a potent endogenous inflammatory agent, to promote malignant transformation of Syrian hamster embryo cells (SHE) initiated by a 0.5-Gy dose of alpha-particles was investigated. Opsonized zymosan particles, which were phagocytosed by a human macrophage-like cell line, triggered TNF-alpha production from U937 cells. This cell supernatant could significantly increase the transformation frequency (TF) of primary SHE cells previously irradiated by a 0.5-Gy dose of alpha-particles. The TF decreased significantly if monoclonal antibody against TNF-alpha was added to the supernatant. Similarly, recombinant human TNF-alpha (rhTNF-alpha) increased the TF of alpha-irradiated primary SHE cells to an even greater extent. Addition of TNF-alpha to subcultures of irradiated SHE cells permitted the continuous propagation of these primary cells. In contrast, both TNF-alpha-treated control and alpha-irradiated cells without subsequent TNF-alpha treatment senesced after 7-15 passages. Irradiated SHE cells treated continuously with TNF-alpha could be subcultured over 40 passages and produced fibrosarcomas upon inoculation into nude mice. Our results provide the first evidence that TNF-alpha released by activated macrophages may contribute to the process of malignant transformation initiated by low-dose alpha-particles.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos da radiação , Fator de Necrose Tumoral alfa/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Transformação Celular Neoplásica/patologia , Células Cultivadas , Cricetinae , Embrião de Mamíferos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Fibroblastos/efeitos da radiação , Fibrossarcoma/patologia , Humanos , Mesocricetus , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Experimentais/patologia , Testes de Neutralização , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/imunologia
18.
Proc Natl Acad Sci U S A ; 93(4): 1648-53, 1996 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-8643685

RESUMO

The observed in vitro and in vivo benefit of combination treatment with anti-human immunodeficiency virus (HIV) agents prompted us to examine the potential of resistance development when two protease inhibitors are used concurrently. Recombinant HIV-1 (NL4-3) proteases containing combined resistance mutations associated with BMS-186318 and A-77003 (or saquinavir) were either inactive or had impaired enzyme activity. Subsequent construction of HIV-1 (NL4-3) proviral clones containing the same mutations yielded viruses that were severely impaired in growth or nonviable, confirming that combination therapy may be advantageous. However, passage of BMS-186318-resistant HIV-1 (RF) in the presence of either saquinavir or SC52151, which represented sequential drug treatment, produced viable viruses resistant to both BMS-186318 and the second compound. The predominant breakthrough virus contained the G48V/A71T/V82A protease mutations. The clone-purified RF (G48V/A71T/V82A) virus, unlike the corresponding defective NL4-3 triple mutant, grew well and displayed cross-resistance to four distinct protease inhibitors. Chimeric virus and in vitro mutagenesis studies indicated that the RF-specific protease sequence, specifically the Ile at residue 10, enabled the NL4-3 strain with the triple mutant to grow. Our results clearly indicate that viral genetic background will play a key role in determining whether cross-resistance variants will arise.


Assuntos
Inibidores da Protease de HIV/farmacologia , Protease de HIV/genética , HIV-1/efeitos dos fármacos , Sequência de Aminoácidos , Carbamatos/farmacologia , Células Clonais , Análise Mutacional de DNA , DNA Recombinante/genética , DNA Viral/genética , Esquema de Medicação , Resistência Microbiana a Medicamentos/genética , Quimioterapia Combinada , Etanolaminas/farmacologia , Inibidores da Protease de HIV/administração & dosagem , HIV-1/enzimologia , HIV-1/genética , Células HeLa , Humanos , Indinavir , Isoquinolinas/farmacologia , Compostos de Metilureia/farmacologia , Dados de Sequência Molecular , Mutação Puntual , Provírus/enzimologia , Provírus/genética , Piridinas/farmacologia , Quinolinas/farmacologia , Vírus Reordenados/efeitos dos fármacos , Vírus Reordenados/genética , Proteínas Recombinantes de Fusão/antagonistas & inibidores , Proteínas Recombinantes de Fusão/metabolismo , Saquinavir , Linfócitos T , Ureia/análogos & derivados , Ureia/farmacologia , Valina/análogos & derivados
19.
Chin Med J (Engl) ; 107(8): 610-4, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7805447

RESUMO

The biological effects of relative low level internal irradiation were introduced. 1. Life span studies on carcinogenesis. Pacific Northwest Laboratory observed 3782 rats given a single inhalation of 239Pu O2 at initial lung burden ranging from 0.25 to 180 nCi. Significant life span shortening was found at lung dose > 8 Gy and it was indicated that the presence of a "possible" threshold of about 1 Gy for lung tumor formation. 2. Health effects of radon and its progeny. Both experimental and epidemiological survey were studied. The nominal probability coefficient (fatality) for the public and workers are 7.90 x 10(5) per mJhm-3 (2.77 x 10(-4) per working level month, WLM). 3. Health effects on 3H on postnatal brain development and neurobehavior, genetic effects, carcinogenic effects and adaptive effects of 3H were investigated. 4. Study on the effects of neuroendocrine system under low level irradiation of 75Se (Auger electron emitter) and 35S (beta-particles emitter). The results showed that the neuroendocrine system is very sensitive to small dose of internal irradiation.


Assuntos
Neoplasias Induzidas por Radiação , Sistemas Neurossecretores/efeitos da radiação , Lesões Experimentais por Radiação , Animais , Humanos , Neoplasias Pulmonares/etiologia , Doses de Radiação
20.
Antimicrob Agents Chemother ; 38(7): 1683-7, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7979311

RESUMO

The acyclic purine nucleoside phosphonates, a newly described class of broad-spectrum antiviral agents, effectively inhibit human immunodeficiency virus type 1 (HIV-1) replication in vitro and in animal AIDS models. 9-(2-Phosphonylmethoxyethyl)adenine (PMEA) is currently being evaluated in clinical trials in patients with AIDS. In this study, we investigated the efficacy of PMEA and a related analog, 9-(2-phosphonylmethoxypropyl)diaminopurine (PMPDAP), against HIV-1 isolates exhibiting various degrees of resistance to zidovudine (azidothymidine [AZT]). HIV isolates highly (approximately 50 to 200-fold) resistant to AZT were found to be about two- to eightfold less susceptible to PMEA. A comparable degree of cross-resistance to PMPDAP, a structurally related analog of PMEA, was also observed. However, the 50% effective dose values of PMEA or PMPDAP against a panel of HIV isolates showing intermediate levels (approximately 8 to 25-fold) of AZT resistance was indistinguishable from the 50% effective dose values of PMEA (0.7 to 1.7 versus 2 microM) or PMPDAP (0.4 to 1.4 versus 0.8 to 1 microM) against HIV isolates from patients who had not previously used AZT. In addition, we were unable to generate PMEA- (or PMPDAP)-resistant HIV-1 variants by > 30 serial passages of the virus in the presence of increasing concentrations of PMEA. Careful analysis of HIV-1 isolates from patients previously treated with AZT for cross-resistance to PMEA are needed to evaluate the significance of these observations.


Assuntos
Adenina/análogos & derivados , Antivirais/farmacologia , HIV-1/efeitos dos fármacos , Organofosfonatos , Compostos Organofosforados/farmacologia , Adenina/farmacologia , Linhagem Celular , Resistência Microbiana a Medicamentos , HIV-1/genética , Humanos , Estrutura Molecular , Linfócitos T/efeitos dos fármacos , Linfócitos T/microbiologia , Zidovudina/farmacologia
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