Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
J Neurosci ; 38(35): 7683-7700, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30054395

RESUMO

Aging contributes to cellular stress and neurodegeneration. Our understanding is limited regarding the tissue-restricted mechanisms providing protection in postmitotic cells throughout life. Here, we show that spinal cord motoneurons exhibit a high abundance of asymmetric dimethyl arginines (ADMAs) and the presence of this posttranslational modification provides protection against environmental stress. We identify protein arginine methyltransferase 8 (PRMT8) as a tissue-restricted enzyme responsible for proper ADMA level in postmitotic neurons. Male PRMT8 knock-out mice display decreased muscle strength with aging due to premature destabilization of neuromuscular junctions. Mechanistically, inhibition of methyltransferase activity or loss of PRMT8 results in accumulation of unrepaired DNA double-stranded breaks and decrease in the cAMP response-element-binding protein 1 (CREB1) level. As a consequence, the expression of CREB1-mediated prosurvival and regeneration-associated immediate early genes is dysregulated in aging PRMT8 knock-out mice. The uncovered role of PRMT8 represents a novel mechanism of stress tolerance in long-lived postmitotic neurons and identifies PRMT8 as a tissue-specific therapeutic target in the prevention of motoneuron degeneration.SIGNIFICANCE STATEMENT Although most of the cells in our body have a very short lifespan, postmitotic neurons must survive for many decades. Longevity of a cell within the organism depends on its ability to properly regulate signaling pathways that counteract perturbations, such as DNA damage, oxidative stress, or protein misfolding. Here, we provide evidence that tissue-specific regulators of stress tolerance exist in postmitotic neurons. Specifically, we identify protein arginine methyltransferase 8 (PRMT8) as a cell-type-restricted arginine methyltransferase in spinal cord motoneurons (MNs). PRMT8-dependent arginine methylation is required for neuroprotection against age-related increased of cellular stress. Tissue-restricted expression and the enzymatic activity of PRMT8 make it an attractive target for drug development to delay the onset of neurodegenerative disorders.


Assuntos
Dano ao DNA/fisiologia , Neurônios Motores/enzimologia , Proteína-Arginina N-Metiltransferases/fisiologia , Envelhecimento/metabolismo , Sequência de Aminoácidos , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Contração Isométrica , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Células Musculares/enzimologia , Células Musculares/fisiologia , Junção Neuromuscular/metabolismo , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Proteína-Arginina N-Metiltransferases/deficiência , Proteína-Arginina N-Metiltransferases/genética , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Reflexo Anormal , Teste de Desempenho do Rota-Rod , Medula Espinal/citologia , Medula Espinal/crescimento & desenvolvimento
2.
J Physiol ; 595(17): 5815-5842, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28714082

RESUMO

KEY POINTS: The in situ phenotypic switch of macrophages is delayed in acute injury following irradiation. The combination of bone marrow transplantation and local muscle radiation protection allows for the identification of a myeloid cell contribution to tissue repair. PET-MRI allows monitoring of myeloid cell invasion and metabolism. Altered cellular composition prior to acute sterile injury affects the in situ phenotypic transition of invading myeloid cells to repair macrophages. There is reciprocal intercellular communication between local muscle cell compartments, such as PAX7 positive cells, and recruited macrophages during skeletal muscle regeneration. ABSTRACT: Skeletal muscle regeneration is a complex interplay between various cell types including invading macrophages. Their recruitment to damaged tissues upon acute sterile injuries is necessary for clearance of necrotic debris and for coordination of tissue regeneration. This highly dynamic process is characterized by an in situ transition of infiltrating monocytes from an inflammatory (Ly6Chigh ) to a repair (Ly6Clow ) macrophage phenotype. The importance of the macrophage phenotypic shift and the cross-talk of the local muscle tissue with the infiltrating macrophages during tissue regeneration upon injury are not fully understood and their study lacks adequate methodology. Here, using an acute sterile skeletal muscle injury model combined with irradiation, bone marrow transplantation and in vivo imaging, we show that preserved muscle integrity and cell composition prior to the injury is necessary for the repair macrophage phenotypic transition and subsequently for proper and complete tissue regeneration. Importantly, by using a model of in vivo ablation of PAX7 positive cells, we show that this radiosensitive skeletal muscle progenitor pool contributes to macrophage phenotypic transition following acute sterile muscle injury. In addition, local muscle tissue radioprotection by lead shielding during irradiation preserves normal macrophage transition dynamics and subsequently muscle tissue regeneration. Taken together, our data suggest the existence of a more extensive and reciprocal cross-talk between muscle tissue compartments, including satellite cells, and infiltrating myeloid cells upon tissue damage. These interactions shape the macrophage in situ phenotypic shift, which is indispensable for normal muscle tissue repair dynamics.


Assuntos
Macrófagos/imunologia , Músculo Esquelético , Lesões Experimentais por Radiação/imunologia , Animais , Transplante de Medula Óssea , Cardiotoxinas , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/imunologia , Músculo Esquelético/lesões , Músculo Esquelético/efeitos da radiação , Fenótipo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Lesões Experimentais por Radiação/diagnóstico por imagem , Regeneração
3.
Mar Drugs ; 10(5): 1044-1065, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22822356

RESUMO

The dinoflagellate Gymnodinium catenatum produces paralyzing shellfish poisons that are consumed and accumulated by bivalves. We performed short-term feeding experiments to examine ingestion, accumulation, biotransformation, histopathology, and paralysis in the juvenile Pacific calico scallop Argopecten ventricosus that consume this dinoflagellate. Depletion of algal cells was measured in closed systems. Histopathological preparations were microscopically analyzed. Paralysis was observed and the time of recovery recorded. Accumulation and possible biotransformation of toxins were measured by HPLC analysis. Feeding activity in treated scallops showed that scallops produced pseudofeces, ingestion rates decreased at 8 h; approximately 60% of the scallops were paralyzed and melanin production and hemocyte aggregation were observed in several tissues at 15 h. HPLC analysis showed that the only toxins present in the dinoflagellates and scallops were the N-sulfo-carbamoyl toxins (C1, C2); after hydrolysis, the carbamate toxins (epimers GTX2/3) were present. C1 and C2 toxins were most common in the mantle, followed by the digestive gland and stomach-complex, adductor muscle, kidney and rectum group, and finally, gills. Toxin profiles in scallop tissue were similar to the dinoflagellate; biotransformations were not present in the scallops in this short-term feeding experiment.


Assuntos
Dinoflagellida/metabolismo , Toxinas Marinhas/toxicidade , Paralisia/induzido quimicamente , Pectinidae/efeitos dos fármacos , Pectinidae/metabolismo , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão/métodos , Métodos de Alimentação , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Hemócitos/metabolismo , Hemócitos/patologia , Hidrólise , Cinética , Toxinas Marinhas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Paralisia/metabolismo , Frutos do Mar
4.
Int J Food Microbiol ; 331: 108715, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32554040

RESUMO

Ground beef contamination with Escherichia coli is usually a result of carcass faecal contamination during the slaughter process. Carcasses are contaminated when they come into contact with soiled hides or intestinal leakage content during dressing and the evisceration processes. A more recent and compelling hypothesis is that, when lymph nodes are present in manufacturing beef trimmings, they can be a potential source of Enterobacteriaceae contamination of ground beef. The aim of this study was to investigate the occurrence of E. coli in lymph nodes from beef carcasses used for ground meat production, in six slaughter plants situated in central Italy A total of 597 subiliac (precrural) lymph nodes were obtained from 597 cattle carcasses and screened for E. coli by culture. Furthermore, E. coli isolates (one per positive carcass) were tested for stx1, stx2 eaeA and hlyA genes that are commonly used to identify and characterise shiga toxin-producing E. coli (STEC). In addition, the E. coli isolates were profiled for antimicrobial susceptibility. A proportion of 34.2% (204/597) carcasses were positive for E. coli. PCR revealed that 29% (59/204) of E. coli possessed stx1 or stx2 which corresponded to 9.9% of the cattle sampled. Moreover, a combination of stx1 or stx2 and eaeA was found in in 4 isolates (2% among E. coli positive samples and 1% among cattle sampled) and a combination of stx1 or stx2 and eaeA and hly in 1 isolate (0.5% and 0.2%). More than 95% of isolates were susceptible to gentamicin, ceftriaxone, cyprofloxacin and cefotaxime while high rates of resistance were recorded for cephalotin, ampicillin, tetracycline, tripe sulfa and streptomycin. The multivariate analysis identified "age" as the factor most closely related to E. coli positivity (either generic E. coli or STEC) in bovine lymph nodes. In conclusion, subiliac lymph nodes represent a source of E. coli for ground beef. These results are of major importance for risk assessment and improving good manufacturing practices during animal slaughter and ground meat production.


Assuntos
Escherichia coli/fisiologia , Linfonodos/microbiologia , Carne/microbiologia , Animais , Bovinos , Escherichia coli/genética , Itália , Reação em Cadeia da Polimerase
5.
AIDS Res Hum Retroviruses ; 24(2): 337-43, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18284328

RESUMO

ABSTRACT The aim of this study was to characterize the HIV-1 intersubtype recombinant forms generated during the follow-up of a dual natural infection with subtypes B and G. Near full-length sequences from plasma and peripheral blood mononuclear cell (PBMC) compartments were analyzed and the biological characteristics of their derived primary isolates studied. Different mutations were detected in V1, V2, and V3 sequences from primary isolates but not in sequences from plasma RNA or PBMC DNA. The HIV-1 near full-length sequence from the first collected plasma was of subtype G and the presence of subpopulations of subtypes B and G was observed with subtype-specific primers for protease and reverse transcriptase segments. Subsequent sequences from plasma, PBMCs, and primary isolates were obtained during a follow-up of 6 years; all of them were BG recombinants and showed identical intersubtype breakpoints between subtypes B and G in pol and nef. The env sequence from all primary isolates harbored a unique insert of subtype B. Specific primers for the V3 loop identified fluctuating subtype B and/or subtype G sequences either from plasma RNA or PBMC DNA.


Assuntos
Evolução Molecular , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , RNA Viral/genética , Recombinação Genética , DNA Viral/sangue , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Seguimentos , HIV-1/isolamento & purificação , Humanos , Leucócitos Mononucleares/virologia , Dados de Sequência Molecular , RNA Viral/sangue , RNA Viral/isolamento & purificação , Análise de Sequência de DNA , Espanha
6.
AIDS Res Hum Retroviruses ; 23(3): 407-14, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17411374

RESUMO

The main objective of this study is to evaluate the prevalence of resistance-associated mutations to reverse transcriptase (RT) and protease (PR) inhibitors (I) 2 years after the introduction of antiretroviral treatment in Cuba, analyzing the mutations corresponding to different HIV-1 genetic forms circulating in Cuba. A total of 425 plasma samples were collected in 2003, corresponding to 175 (41.2%) subtype B and 250 (58.8%) non-B genetic forms, including 56 (22.4 %) non-B subtypes, 112 (44.8%) circulating recombinant forms (CRFs), and 82 (32.8%) unique RFs (URFs). Of these, 175 (41.2%) patients were under highly active antiretroviral therapy (HAART) and 250 (58.8%) were treatment-naive. The presence of RT and PR resistance-associated mutations was established by sequencing. Levels of resistance were evaluated according to the Stanford Database program (http://hivdb.stanford.edu). The prevalence of resistance to RTI was 52.2% among RTI-treated patients, 51.5% for subtype B, and 53.2% for non-B genetic forms, including CRF18_cpx, CRF19_cpx, subtype C, and BG URF. In treatment-naive patients it was 6.4% in subtype B and 4.2% in non-B subtypes and RFs. The prevalence of resistance to PRI was 30% among PRI-treated patients, 28% in subtype B and 31% in non-B genetic forms, and 3.2% among treatment-naive subjects, mostly BG recombinants. In conclusion, significant differences in the prevalence of resistance to RTI and PRI were not detected among the most frequent genetic forms from treated patients, suggesting that the genetic diversity of HIV-1 in Cuba does not play a main role in the development of resistance to antiretroviral drugs. The presence of transmitted resistance mutations supports the study of resistance at baseline of treatment.


Assuntos
Farmacorresistência Viral Múltipla/genética , Infecções por HIV/genética , Protease de HIV , Transcriptase Reversa do HIV , HIV-1/efeitos dos fármacos , HIV-1/genética , Terapia Antirretroviral de Alta Atividade , Sequência de Bases , Estudos Transversais , Cuba/epidemiologia , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Protease de HIV/classificação , Protease de HIV/genética , Transcriptase Reversa do HIV/classificação , Transcriptase Reversa do HIV/genética , HIV-1/classificação , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Inibidores de Proteases/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico
7.
AIDS Res Hum Retroviruses ; 23(12): 1599-604, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18160020

RESUMO

The HIV-1 subtype A epidemic affecting injecting drug users (IDU) in former Soviet Union (FSU) countries started dramatically in Odessa, southern Ukraine, in 1995, and is caused by a variant of monophyletic origin, often designated IDU-A. We phylogenetically analyzed one near full-length genome and two partial sequences of three HIV-1 subtype A viruses collected in St. Petersburg, Russia, heterosexually transmitted in 1992-1994. The sequences branched basally to the IDU-A clade, together with eight viruses from Odessa collected in 1993, all presumably acquired heterosexually, and two viruses from the Democratic Republic of Congo. Of all other FSU sequences in databases, only those from three recently collected viruses, one from Ukraine and two from northwestern Russia, at least one of them acquired heterosexually, branched basally to the IDU-A cluster. The results indicate that the FSU IDU-A variant derives from a strain that initially propagated heterosexually in Ukraine and originated in central Africa.


Assuntos
Genoma Viral , Infecções por HIV/epidemiologia , HIV-1/genética , Sequência de Bases , República Democrática do Congo/epidemiologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/classificação , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Federação Russa/epidemiologia , Abuso de Substâncias por Via Intravenosa/virologia , Ucrânia/epidemiologia
8.
Infect Genet Evol ; 5(3): 209-17, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15737911

RESUMO

Human immunodeficiency virus type 1 (HIV-1) BF intersubtype recombinant viruses are common in Argentina and Uruguay, where CRF12_BF and related recombinants are frequently found, and, in a lower proportion, in Brazil. Full-length genome sequences have been characterized in several of these recombinant viruses. Here, we analyze six newly derived near full-length genome sequences of BF recombinant viruses, three from Chile, one from Venezuela and two from Spain. Five of them had known epidemiological links to Argentina. Genomes were amplified by PCR from plasma RNA or from peripheral blood mononuclear cells' DNA. Mosaic structures and phylogenetic relationships were analyzed by bootscanning, neighbour-joining phylogenetic trees and by examination of subtype signature nucleotides. One virus from Spain had a mosaic structure fully coincident with CRF12_BF. The others had unique mosaic structures, except the viruses from two Chilean sisters infected vertically from the same mother, who showed identical recombination patterns. Each of the unique recombinants had one to six breakpoints coincident with CRF12_BF and three also had two or three breakpoints coincident with a previously characterized unique recombinant from Argentina (A025) related to CRF12_BF. A phylogenetic tree of concatenated subtype F segments supported the relationship of five recombinants with CRF12_BF. In trees of partial subtype F and B segments, four recombinants clustered with A025. The examination of CRF12_BF signature amino acids and nucleotides supported the common ancestry of all the analyzed viruses. Based on these results, a model of generation of HIV-1 BF recombinants of Argentinean ancestry by successive rounds of recombination along diverse lineages deriving from a common BF recombinant ancestor related to CRF12_BF is proposed.


Assuntos
Genoma Viral , HIV-1/genética , Recombinação Genética , Argentina , Chile , Feminino , Variação Genética , Infecções por HIV/genética , Humanos , Masculino , Filogenia , Análise de Sequência de DNA , Espanha , Venezuela
9.
J Clin Virol ; 33(3): 224-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15911444

RESUMO

BACKGROUND: Genotypic and phenotypic analysis of HIV-1 resistance mutations constitute one important point for providing guidelines in the choice of antiretroviral regimens and to design lines of rescue treatment for patients holding HIV-1 drug-resistant variants. However, some levels of discordance among them has been described. OBJECTIVES: (i) To compare the genotypic analysis of resistance mutations to reverse transcriptase (RT) and protease (PR) inhibitors by Stanford HIVdb program (http://hivdb.stanford.edu) (St-HIVdb), and genotype with quantitative phenotypic analysis (Virtual Phenotype, VircoNET). (ii) To identify drug resistance mutations associated with discrepant results. STUDY DESIGN: Five hundred HIV-1 infected patients were included in this study. RNA was extracted from plasma. RT and PR regions were amplified and sequenced using ABI-Prism DNA sequencing system. Sequences were corrected and assembled with Seqman and Bioedit computer programs. The corrected sequences were submitted to the Stanford HIV-Seq program (http://hivdb.stanford.edu) and to Virtual Phenotype (VircoNET). RESULTS: Discrepant cases were considered if results were high or intermediate resistant by Stanford HIV-Seq program and susceptible by Virtual Phenotype, being detected as follows: (i) nucleoside RT inhibitors (NRT): 31.7% (ABC), 31% (d4T), 29.5% (ddC), 27.6% (ddI), 14.3% (TDF) and 11.3% (ZDV) and to PR inhibitors: 8.8% (SQV), 5% (APV), 3.8% (NFV) and 3.2% (IDV). These discrepant results were related to the presence of thymidine analogue mutations (TAMs) and also to key resistance mutations to NRT inhibitors: 65R, 69D/N, 74V/I, 184V/I and 215Y/F. (ii) PR inhibitors: 82A/F/T/S, 84I and 90M. Concordant results were considered when the interpretations by both programs were coincident, being higher than 96.7% for non-NRT inhibitors. CONCLUSIONS: The detection of discrepant results to NRT inhibitors and PR inhibitors, including the analysis of sequences with key resistant mutations to some drugs, means that further investigation is necessary in order to establish which is the best interpretation system as antiretroviral therapy guide.


Assuntos
Fármacos Anti-HIV/farmacologia , Biologia Computacional/métodos , HIV-1/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Algoritmos , Farmacorresistência Viral/genética , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/enzimologia , HIV-1/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Fenótipo , RNA Viral/sangue , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Software
10.
Antivir Ther ; 8(4): 355-60, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14518705

RESUMO

The objectives of this study are to describe the incidence of non-B and recombinant HIV-1 strains in newly diagnosed HIV-1 infections in Galicia, northwest of Spain, during a 2-year period (May 2000 to June 2002), and the frequency of resistance-associated mutations in reverse transcriptase (RT) and protease (PR) genes, analysing the polymorphisms more frequently detected in non-B and recombinant viruses. All newly diagnosed HIV-1-infected patients attending the nine public hospitals of the seven main cities of Galicia were included in this study. RT, PR and V3 regions from HIV-1 RNA plasma were amplified and sequenced, being the corrected sequences sent to the Stanford HIV RT and Protease Sequence Database. Nineteen of 85 patients (22.3%) were infected by non-B or recombinant viruses: three subtype C, two G, one F1, one Dpol/A1V3, five CRF02_AG, one CRF14_BG, five BGpol/BV3 and one UKpol/UV3 (U, unknown fragment). Eleven of these 19 patients (57.9%) were foreign individuals living in Galicia infected through heterosexual contact, and the other eight (42.1%) were Spanish intravenous drug users who had shared injection equipment. Five of 85 patients (5.9%), all infected with B subtype viruses, showed resistance-associated mutations in RT (M184V, M41L, L210W, T215Y/D and K219Q). In one patient (1.2%) infected with a subtype G strain, resistance-associated mutations in PR (K20I+M36I+M46I+V82I) were detected. In subtype B viruses resistance mutations in PR were not detected. Several polymorphisms in RT: D123S, Q174K, D177E, T200A, V245Q, and PR: I13V, K20I, M36I, R41K, H69K, L89M were detected more frequently in non-B and recombinants than in B strains (P<0.01 to P<0.001). This study reports a high incidence (22.3%) of newly diagnosed patients infected by different non-B and recombinant HIV-1 strains, in a geographical area of Spain, showing also a high frequency of polymorphisms in RT and PR genes.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/isolamento & purificação , Recombinação Genética , Adulto , Idoso , Fármacos Anti-HIV/farmacologia , Feminino , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mutação , RNA Viral/sangue , Espanha/epidemiologia
11.
J Acquir Immune Defic Syndr ; 51(1): 99-103, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19282784

RESUMO

OBJECTIVE: To determine the introduction of HIV-1 genetic forms and to examine transmission clusters and resistance to antiretroviral inhibitors among newly diagnosed patients from the Basque Country, Spain, during 2004-2007. METHODS: A total of 261 samples, corresponding to 47.5% heterosexuals, 37.9% men who have sex with men (MSM), and 11.1% intravenous drug users were analyzed in protease and reverse transcriptase to examine phylogenetic relationships and drug resistance-associated mutations. RESULTS: Subtype B was detected in 220 (84.3%) samples and non-B subtype variants in 41 (15.7%) samples. Nearly half (47%) of the sequences grouped in transmission clusters. One of these comprised 14 individuals, 12 of them MSM, with the T215D revertan mutation. In largest transmission clusters, the percentage of MSM was higher than heterosexuals (P < 0.001). Resistance mutations were detected in 29 (11.1%) patients: 20 (7.6%) of them to nucleoside reverse transcriptase inhibitor; 6 (2.3%) to nonnucleoside reverse transcriptase inhibitor (NNRTI); and 1 each to protease inhibitors, protease inhibitor plus NNRTI, and nucleoside reverse transcriptase inhibitor plus NNRTI, respectively. CONCLUSIONS: Our findings underscore recommendations for HIV-1 genotyping in newly diagnosed patients not only to provide information on transmitted drug resistance as an issue in public health and as a guide to future therapy but also to document transmission clusters and to increase the necessary preventive measures.


Assuntos
Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/genética , Análise por Conglomerados , Farmacorresistência Viral/genética , Feminino , Genes pol , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/efeitos dos fármacos , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Filogenia , RNA Viral/genética , Comportamento Sexual , Espanha/epidemiologia , Abuso de Substâncias por Via Intravenosa
12.
J Med Virol ; 78(12): 1520-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17063519

RESUMO

The biological characteristics of HIV-1 primary isolates of different recombinant forms (RFs) and non-B subtypes from Galicia, Spain, were investigated and the relationships between biological phenotype and evolution of infection were determined. Peripheral blood mononuclear cells (PBMCs) were obtained during the follow-up of 32 patients infected with HIV-1 non-subtype B genetic forms, characterized in partial sequences of pol (protease-reverse transcriptase) and env V3 region: 12 (37.5%) circulating RFs (CRFs), 9 (28.1%) unique RFs (URFs), and 11(34.4%) non-B subtypes. Primary isolates were obtained by coculture with donor PBMCs. Syncytium-inducing (SI) phenotype was examined in MT2 cell line and coreceptor use in GHOST and U87.CD4 cells. Fifty percent of tissue culture infective dose (TCID(50)) and viral phenotype based on V3 net charge and Geno2pheno(coreceptor) bioinformatic method were determined. Fifty-four HIV-1 primary isolates were obtained. CRF14_BG and BG URFs represented the largest group, being all SI/X4, independently of the CD4+ cell count, viral load, or the duration of infection. By contrast, 10 of 11 CRF02_AG viruses were NSI/R5. The prediction of co-receptor use was concordant with biological characterization in all NSI/R5 and in 23 of 26 SI/X4 isolates. The presence of SI/X4 or SI/X4,R5 isolates at early stages of the infection in addition to a decrease in CD4+ counts below 500 cells/microl between 2 and 6 years since diagnosis was observed in all patients infected with CRF14_BG and BG URFs. These data contrast with the usual progression in B subtype infections, in which SI/X4 viruses rarely predominate in the early years of HIV-1 infection.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/isolamento & purificação , Recombinação Genética , Sequência de Aminoácidos , Linhagem Celular Tumoral , Células Gigantes/fisiologia , Proteína gp120 do Envelope de HIV/genética , HIV-1/genética , HIV-1/patogenicidade , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fenótipo , Análise de Sequência de DNA , Espanha/epidemiologia
13.
J Clin Microbiol ; 43(10): 5301-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16208003

RESUMO

The oligonucleotide ligation assay is a genotypic assay for the detection of resistance-associated mutations to reverse transcriptase and protease inhibitors in human immunodeficiency virus type 1 subtype B. This assay has been modified and developed for non-B subtypes and recombinant strains and has been evaluated with sequencing, resulting in a more sensitive assay than sequencing for non-B subtypes.


Assuntos
Fármacos Anti-HIV/farmacologia , DNA Ligases/metabolismo , Farmacorresistência Viral/genética , Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , Oligonucleotídeos/metabolismo , Mutação Puntual , Inibidores da Transcriptase Reversa/farmacologia , Produtos do Gene pol/genética , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Humanos , Testes de Sensibilidade Microbiana/métodos , Oligonucleotídeos/química , Oligonucleotídeos/genética , RNA Viral/sangue , Recombinação Genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Fatores de Tempo
14.
J Neurovirol ; 9(5): 551-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-13129769

RESUMO

Progressive multifocal leukoencephalopathy (PML) is a fatal demyelinating disease of the central nervous system (CNS) caused by the human polyomavirus JC (JCV). JCV has a hypervariable noncoding transcriptional control region (TCR) that spans the origin of replication of the JCV genome through to the first ATG start codon for late gene transcription. The archetype form of TCR is frequently found in the urine and kidneys of healthy and immunocompromised subjects. However the rearranged forms, whose prototype is Mad-1, possibly generated by deletion and duplication of segments of the archetype sequence, are found in the brain and cerebrospinal fluid (CSF) of PML patients. In this study the authors compared JCV TCR detected in paired CSF, plasma, and urine samples of 11 acquired immunodeficiency syndrome (AIDS) patients affected by PML to try to determine where the rearranged JCV TCRs are selected. In one patient, it was also possible to amplify and sequence the TCR in the brain and lymphocytes. Moreover, in 5/11 patients, the CSF, plasma, and urine samples corresponding to 2 months after PML development were available; and in another patient, it was possible to sequence the TCR in plasma and lymphocytes sampled 8 months before the onset of PML. The presence of the same TCR sequences in all the CSF and plasma samples taken from individual patients could strengthen the hypothesis that the blood is a compartment where JCV may replicate and undergo rearrangement of the TCR. This further supports the hypothesis that JCV reaches the brain by a hematogenous route and indicates that the JCV TCR sequences detected in plasma could be used as an early marker of JCV pathogenicity before the clinical appearance of PML in immunocompromised patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/virologia , Síndrome da Imunodeficiência Adquirida/líquido cefalorraquidiano , Síndrome da Imunodeficiência Adquirida/virologia , DNA Viral/genética , Regulação Viral da Expressão Gênica/genética , Rearranjo Gênico , Vírus JC/genética , Leucoencefalopatia Multifocal Progressiva/virologia , Transcrição Gênica , Síndrome da Imunodeficiência Adquirida/complicações , Sequência de Bases , Primers do DNA , DNA Viral/líquido cefalorraquidiano , DNA Viral/isolamento & purificação , Humanos , Vírus JC/isolamento & purificação , Leucoencefalopatia Multifocal Progressiva/etiologia , Reação em Cadeia da Polimerase
15.
Rev. ADM ; 51(3): 139-44, mayo-jun. 1994. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-139627

RESUMO

En la Escuela de Odontología de la Universidad del Bajío, ubicada en la ciudad de León, Gto., se realizó una investigación utilizando el rayo láser blando, bajo las siguientes circunstancias: 50 pacientes de ambos sexos; 15 con úlceras aftosas menores recurrentes y 35 con úlceras herpéticas, fueron tratados con rayo láser blando, He-Ne. Con un potencial medio de 7 nw y con un diaámetro del Haz de 0.85 mm. Se les aplicó una dosis total de 7 julios, repartidos hasta en 5 días, para comprobar su eficacia como tratamiento de estas lesiones. Se reporta la pronta cicatrización de las lesiones, así como la notable disminución del dolor, como resultado del tratamiento


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Adolescente , Adulto , Pessoa de Meia-Idade , Estomatite Herpética/terapia , Herpes Labial/terapia , Lasers/uso terapêutico , Estomatite Aftosa/terapia , México
16.
Arch. med. res ; Arch. med. res;28(1): 5-9, mar. 1997. ilus
Artigo em Inglês | LILACS | ID: lil-225190

RESUMO

We report a study on the DNA organization in Entamoeba histolytica using a ribosomal DNA probe. The rDNA genes were found forming mers which were separated in a typical ladder pattern by pulse field electrophoresis. DNA rosette structures were visualized through electron microscopy in DNA eluted from bands recognized by the ribosomal probe. The in situ hybridization experiments using a DNA probe suggested that the rDNA genes are portioned between the nucleus and a cytoplasmic structure. These findings provide new data on DNA organization in E. histolytica and open the question concerning the presence of a novel organelle in this eukaryotic parasite


Assuntos
Animais , DNA Ribossômico/genética , DNA Ribossômico/ultraestrutura , Citoplasma/química , DNA de Protozoário/genética , DNA de Protozoário/ultraestrutura , Entamoeba histolytica/genética , Entamoeba histolytica/ultraestrutura , Hibridização In Situ
17.
Med. fam. (Caracas) ; 7(1): 6-12, ene.-jun. 1999. tab, graf
Artigo em Espanhol | LILACS | ID: lil-391280

RESUMO

La familia es un conjunto de personas interactuantes, atadas al "clima" que ellas crean y en el cual se desenvuelven. El clima familiar nos aproxima a entender el comportamiento interpersonal de los miembros de una familia y evaluar su calidad funcional. Esta investigación es un estudio de campo, descriptivo, del clima familiar del estado Táchira, basado en la escala de clima familiar realizada y adaptada a Venezuela por Williams y colaboradores. El objetivo es elaborar el clima familiar para el Táchira; compararlo con el clima familiar venezolano; y determinar si existen diferencias entre estados socioeconómicos y la procedencia geográfica de las familias tachirenses. Se utilizó como instrumento la escala de clima familiar y el método de Graffar. Se seleccionó, aleatoriamente, una muestra de 136 familias. Al comparar el clima familiar nacional con los resultados obtenidos en el táchira no hubo grandes diferencias entre ambos, a excepción de la escala de control, que aparece con dos deciles menos para el Táchira; la escala de conflicto supera en un decil al parámetro nacional. Se observa una diferencia a favor del Táchira en la escala moral y religiosa y una diferencia significativa para el parámetro nacional en la escala orientación intelectual y cultural.


Assuntos
Humanos , Fatores Culturais , Relações Familiares , Relações Interpessoais , Núcleo Familiar , Orientação , Venezuela
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA