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1.
Retrovirology ; 16(1): 13, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036006

RESUMO

BACKGROUND: HIV-1 patients receiving combination antiretroviral therapy (cART) survive infection but require life-long adherence at high expense. In chronic cART-treated patients with undetectable viral titers, cell-associated viral RNA is still detectable, pointing to low-level viral transcriptional leakiness. To date, there are no FDA-approved drugs against HIV-1 transcription. We have previously shown that F07#13, a third generation Tat peptide mimetic with competitive activity against Cdk9/T1-Tat binding sites, inhibits HIV-1 transcription in vitro and in vivo. RESULTS: Here, we demonstrate that increasing concentrations of F07#13 (0.01, 0.1, 1 µM) cause a decrease in Tat levels in a dose-dependent manner by inhibiting the Cdk9/T1-Tat complex formation and subsequent ubiquitin-mediated Tat sequestration and degradation. Our data indicate that complexes I and IV contain distinct patterns of ubiquitinated Tat and that transcriptional inhibition induced by F07#13 causes an overall reduction in Tat levels. This reduction may be triggered by F07#13 but ultimately is mediated by TAR-gag viral RNAs that bind suppressive transcription factors (similar to 7SK, NRON, HOTAIR, and Xist lncRNAs) to enhance transcriptional gene silencing and latency. These RNAs complex with PRC2, Sin3A, and Cul4B, resulting in epigenetic modifications. Finally, we observed an F07#13-mediated decrease of viral burden by targeting the R region of the long terminal repeat (HIV-1 promoter region, LTR), promoting both paused polymerases and increased efficiency of CRISPR/Cas9 editing in infected cells. This implies that gene editing may be best performed under a repressed transcriptional state. CONCLUSIONS: Collectively, our results indicate that F07#13, which can terminate RNA Polymerase II at distinct sites, can generate scaffold RNAs, which may assemble into specific sets of "RNA Machines" that contribute to gene regulation. It remains to be seen whether these effects can also be seen in various clades that have varying promoter strength, mutant LTRs, and in patient samples.


Assuntos
Regulação Viral da Expressão Gênica/efeitos dos fármacos , HIV-1/genética , RNA não Traduzido/genética , Transcrição Gênica , Antirretrovirais/farmacologia , Biomimética , Sistemas CRISPR-Cas , Linhagem Celular , Edição de Genes , Inativação Gênica , HIV-1/efeitos dos fármacos , Humanos , Regiões Promotoras Genéticas , RNA Viral/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/química
2.
J Biol Chem ; 291(3): 1251-66, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26553869

RESUMO

HIV-1 infection results in a chronic illness because long-term highly active antiretroviral therapy can lower viral titers to an undetectable level. However, discontinuation of therapy rapidly increases virus burden. Moreover, patients under highly active antiretroviral therapy frequently develop various metabolic disorders, neurocognitive abnormalities, and cardiovascular diseases. We have previously shown that exosomes containing trans-activating response (TAR) element RNA enhance susceptibility of undifferentiated naive cells to HIV-1 infection. This study indicates that exosomes from HIV-1-infected primary cells are highly abundant with TAR RNA as detected by RT-real time PCR. Interestingly, up to a million copies of TAR RNA/µl were also detected in the serum from HIV-1-infected humanized mice suggesting that TAR RNA may be stable in vivo. Incubation of exosomes from HIV-1-infected cells with primary macrophages resulted in a dramatic increase of proinflammatory cytokines, IL-6 and TNF-ß, indicating that exosomes containing TAR RNA could play a direct role in control of cytokine gene expression. The intact TAR molecule was able to bind to PKR and TLR3 effectively, whereas the 5' and 3' stems (TAR microRNAs) bound best to TLR7 and -8 and none to PKR. Binding of TAR to PKR did not result in its phosphorylation, and therefore, TAR may be a dominant negative decoy molecule in cells. The TLR binding through either TAR RNA or TAR microRNA potentially can activate the NF-κB pathway and regulate cytokine expression. Collectively, these results imply that exosomes containing TAR RNA could directly affect the proinflammatory cytokine gene expression and may explain a possible mechanism of inflammation observed in HIV-1-infected patients under cART.


Assuntos
Fatores Ativadores da Transcrição/metabolismo , Citocinas/metabolismo , Exossomos/metabolismo , HIV-1/imunologia , Leucócitos/metabolismo , MicroRNAs/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular , Linhagem Celular Transformada , Transformação Celular Viral , Células Cultivadas , Exossomos/imunologia , Exossomos/virologia , Infecções por HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Interleucina-6/metabolismo , Leucócitos/imunologia , Leucócitos/virologia , Linfotoxina-alfa/metabolismo , Camundongos Endogâmicos NOD , Camundongos Transgênicos , MicroRNAs/sangue , Receptor 3 Toll-Like/antagonistas & inibidores , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , eIF-2 Quinase/antagonistas & inibidores , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
3.
J Biol Chem ; 289(32): 22284-305, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-24939845

RESUMO

Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. The HTLV-1 transactivator protein Tax controls many critical cellular pathways, including host cell DNA damage response mechanisms, cell cycle progression, and apoptosis. Extracellular vesicles called exosomes play critical roles during pathogenic viral infections as delivery vehicles for host and viral components, including proteins, mRNA, and microRNA. We hypothesized that exosomes derived from HTLV-1-infected cells contain unique host and viral proteins that may contribute to HTLV-1-induced pathogenesis. We found exosomes derived from infected cells to contain Tax protein and proinflammatory mediators as well as viral mRNA transcripts, including Tax, HBZ, and Env. Furthermore, we observed that exosomes released from HTLV-1-infected Tax-expressing cells contributed to enhanced survival of exosome-recipient cells when treated with Fas antibody. This survival was cFLIP-dependent, with Tax showing induction of NF-κB in exosome-recipient cells. Finally, IL-2-dependent CTLL-2 cells that received Tax-containing exosomes were protected from apoptosis through activation of AKT. Similar experiments with primary cultures showed protection and survival of peripheral blood mononuclear cells even in the absence of phytohemagglutinin/IL-2. Surviving cells contained more phosphorylated Rb, consistent with the role of Tax in regulation of the cell cycle. Collectively, these results suggest that exosomes may play an important role in extracellular delivery of functional HTLV-1 proteins and mRNA to recipient cells.


Assuntos
Produtos do Gene tax/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Linhagem Celular , Sobrevivência Celular , Células Dendríticas/imunologia , Células Dendríticas/fisiologia , Células Dendríticas/virologia , Exossomos/metabolismo , Exossomos/virologia , Produtos do Gene tax/imunologia , Infecções por HTLV-I/etiologia , Infecções por HTLV-I/fisiopatologia , Infecções por HTLV-I/virologia , Interações Hospedeiro-Patógeno , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Virulência , Receptor fas/antagonistas & inibidores
4.
J Virol ; 88(2): 1189-208, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24227837

RESUMO

The implementation of new antiretroviral therapies targeting transcription of early viral proteins in postintegrated HIV-1 can aid in overcoming current therapy limitations. Using high-throughput screening assays, we have previously described a novel Tat-dependent HIV-1 transcriptional inhibitor named 6-bromoindirubin-3'-oxime (6BIO). The screening of 6BIO derivatives yielded unique compounds that show potent inhibition of HIV-1 transcription. We have identified a second-generation derivative called 18BIOder as an inhibitor of HIV-1 Tat-dependent transcription in TZM-bl cells and a potent inhibitor of GSK-3ß kinase in vitro. Structurally, 18BIOder is half the molecular weight and structure of its parental compound, 6BIO. More importantly, we also have found a different GSK-3ß complex present only in HIV-1-infected cells. 18BIOder preferentially inhibits this novel kinase complex from infected cells at nanomolar concentrations. Finally, we observed that neuronal cultures treated with Tat protein are protected from Tat-mediated cytotoxicity when treated with 18BIOder. Overall, our data suggest that HIV-1 Tat-dependent transcription is sensitive to small-molecule inhibition of GSK-3ß.


Assuntos
Fármacos Anti-HIV/farmacologia , Inibidores Enzimáticos/farmacologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Neurônios/virologia , Fármacos Neuroprotetores/farmacologia , Replicação Viral/efeitos dos fármacos , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Fármacos Anti-HIV/química , Inibidores Enzimáticos/química , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Infecções por HIV/tratamento farmacológico , Infecções por HIV/enzimologia , HIV-1/genética , HIV-1/fisiologia , Humanos , Indóis/química , Indóis/farmacologia , Fármacos Neuroprotetores/química , Oximas/química , Oximas/farmacologia , Transcrição Gênica/efeitos dos fármacos , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
5.
J Neurovirol ; 21(3): 257-75, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25672887

RESUMO

Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high-throughput proteomic assays, we have previously identified Bruton's tyrosine kinase (BTK) as a host protein that was uniquely upregulated in the plasma membrane of human immunodeficiency virus (HIV-1)-infected T cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant upregulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells; however, new BTK protein complexes were identified and distributed in both high molecular weight (∼600 kDa) and a small molecular weight complex (∼60-120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1-infected cells using small interfering RNA (siRNA) resulted in selective death of infected, but not uninfected, cells. Using BTK-specific antibody and small-molecule inhibitors including LFM-A13 and a FDA-approved compound, ibrutinib (PCI-32765), we have found that HIV-1-infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1-infected cells are sensitive to treatments targeting BTK expressed in infected cells.


Assuntos
Infecções por HIV/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/metabolismo , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia , Amidas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Citometria de Fluxo , Técnicas de Silenciamento de Genes , HIV-1 , Ensaios de Triagem em Larga Escala , Humanos , Immunoblotting , Camundongos , Nitrilas/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Piperidinas , Proteômica , Pirazóis/farmacologia , Pirimidinas/farmacologia , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
6.
J Contemp Dent Pract ; 16(4): 299-303, 2015 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-26067733

RESUMO

AIM: This analysis was aimed to determine the mesiodistal tooth width of human teeth and to compare with the measurements on plaster model in a Bangladeshi population. MATERIALS AND METHODS: The samples of 2,892 teeth of Bangladeshi subjects were collected for this purpose. This article presents mesiodistal tooth width measurements made on all types of teeth and compares with the mesiodistal tooth width measurements of dental cast collected from Bangladeshi subjects between the ages of 18 and 24 years. The mesiodistal dimension was recorded, involving the maximum mesiodistal dimension of each tooth when measurement was rendered parallel to the occlusal and labial surfaces. Descriptive and comparative statistics were applied. RESULTS: The mean, standard deviation and 95% confidence interval of mesiodistal tooth width measurements were determined and have been with the mesiodistal tooth width measurements of dent al cast. Significant differences have been observed between mesiodistal tooth size of direct measurement on tooth (DMT) and measurement on plaster model (MPM) for the maxillary first molar (p < 0.001) and mandibular incisors to first premolar (p < 0.001). CONCLUSION: These data should prove to be helpful to the practitioner for performing successful orthodontic treatment in Bangladeshi population. CLINICAL SIGNIFICANCE: Direct measurement of mesiodistal tooth width and individual variation of maxillary and mandibular permanent central incisor to first molar of the Bangladeshi individuals showed some distinguishable features, which will certainly help an orthodontist for diagnosis and treatment plan of an orthodontic case.


Assuntos
Modelos Dentários , Odontometria/métodos , Dente/anatomia & histologia , Adolescente , Bangladesh , Dente Pré-Molar/anatomia & histologia , Sulfato de Cálcio/química , Dente Canino/anatomia & histologia , Materiais Dentários/química , Feminino , Humanos , Incisivo/anatomia & histologia , Masculino , Dente Molar/anatomia & histologia , Adulto Jovem
7.
J Neurovirol ; 20(3): 199-208, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24578033

RESUMO

Exosomes are small membrane-bound vesicles that carry biological macromolecules from the site of production to target sites either in the microenvironment or at distant sites away from the origin. Exosomal content of cells varies with the cell type that produces them as well as environmental factors that alter the normal state of the cell such as viral infection. Human DNA and RNA viruses alter the composition of host proteins as well as incorporate their own viral proteins and other cargo into the secreted exosomes. While numerous viruses can infect various cell types of the CNS and elicit damaging neuropathologies, few have been studied for their exosomal composition, content, and function on recipient cells. Therefore, there is a pressing need to understand how DNA and RNA viral infections in CNS control exosomal release. Some of the more recent studies including HIV-1, HTLV-1, and EBV-infected B cells indicate that exosomes from these infections contain viral miRNAs, viral transactivators, and a host of cytokines that can control the course of infection. Finally, because exosomes can serve as vehicles for the cellular delivery of proteins and RNA and given that the blood-brain barrier is a formidable challenge in delivering therapeutics to the brain, exosomes may be able to serve as ideal vehicles to deliver protein or RNA-based therapeutics to the brain.


Assuntos
Viroses do Sistema Nervoso Central/patologia , Viroses do Sistema Nervoso Central/virologia , Exossomos/patologia , Exossomos/virologia , Complexo AIDS Demência/patologia , Complexo AIDS Demência/virologia , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Infecções por HTLV-I/patologia , Infecções por HTLV-I/virologia , Humanos , RNA Viral
8.
Med Gas Res ; 13(3): 118-122, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36571376

RESUMO

Sublingual (SL) buprenorphine is approved for managing acute postoperative pain, characterized by easy administration, good pain relief and good patient compliance. We hypothesized that SL buprenorphine would be a better perioperative analgesic compared to intravenous (IV) opioids like tramadol in patients undergoing mastectomy surgery for breast cancer. After institutional ethics committee approval, we randomized 60 patients with breast cancer into 2 groups. In buprenorphine group, patients received 200 µg of SL buprenorphine thrice daily and in tramadol group patients received 100 mg of IV tramadol thrice daily. The analgesic efficacy of SL buprenorphine was comparable to that of IV tramadol. Visual Analogue Scale scores had no significant difference between the two groups at various time frames (0, 1, 3, 6, 12, 18 and 24 hours) at rest and movement except at 0 and 3 hours during movement when the score was lower in the tramadol group than the buprenorphine group. Four patients in the buprenorphine group received rescue analgesic (IV morphine 3 mg). Analgesic efficacy of SL buprenorphine appears comparable to IV tramadol for managing postoperative pain after mastectomy. SL buprenorphine can be administered sublingually, which is an advantage.


Assuntos
Neoplasias da Mama , Buprenorfina , Tramadol , Humanos , Feminino , Tramadol/uso terapêutico , Buprenorfina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Mastectomia/efeitos adversos , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico
9.
BMJ Open ; 12(2): e051579, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35140148

RESUMO

OBJECTIVE: To evaluate the extent of hydroxychloroquine-induced corrected QT (QTc) prolongation and its relation to COVID-19 infection severity and incidence of polymorphic ventricular arrhythmias and sudden arrhythmic deaths. DESIGN: A large-scale cohort study with retrospective analysis of baseline and on-therapy QT interval corrected using Bazett and Fridericia formulas. SETTING: A multicentre study involving eight secondary and tertiary care hospitals of the Abu Dhabi Health Services Company (SEHA), United Arab Emirates. PARTICIPANTS: 2014 patients consecutively admitted with PCR-confirmed SARS-CoV-2 infection between 1 March 2020 and 1 June 2020. INTERVENTIONS: Treatment with hydroxychloroquine alone or in combination with azithromycin for at least 24 hours and with a baseline ECG and at least one ECG after 24 hours of therapy. MAIN OUTCOME MEASURES: Maximal QTc interval prolongation and its relationship to clinical severity, polymorphic ventricular tachycardia and sudden arrhythmic death while on treatment. RESULTS: The baseline QTc(Bazett) was 427.6±25.4 ms and the maximum QTc(Bazett) during treatment was 439.2±30.4 ms (p<0.001). Severe QTc prolongation (QTc ≥500 ms) was observed in 1.7%-3.3% of patients (Fridericia and Bazett, respectively). There were no cases of polymorphic ventricular arrhythmia or hydroxychloroquine-related arrhythmic death. QTc prolongation was more pronounced in combination therapy compared with hydroxychloroquine alone (22.2 ms vs 11.0 ms, p<0.001) and in patients with higher COVID-19 clinical severity (asymptomatic: 428.4±25.4 ms, severe COVID-19 infection: 452.7±35.7 ms, p<0.001). The overall in-hospital mortality was 3.97% and deceased patients had longer on-therapy QTc(Bazett) than survivors (459.8±21.4 ms vs 438.4±29.9 ms, p<0.001). CONCLUSIONS: The incidence of severe QTc prolongation with hydroxychloroquine was low and not associated with ventricular arrhythmia. The safety concerns surrounding the use of hydroxychloroquine may have been overestimated; however, caution should be exercised when using hydroxychloroquine in patients with risk factors for QT prolongation.


Assuntos
Tratamento Farmacológico da COVID-19 , Hidroxicloroquina , Azitromicina , Estudos de Coortes , Eletrocardiografia , Humanos , Hidroxicloroquina/efeitos adversos , Estudos Retrospectivos , SARS-CoV-2
10.
Indian J Cancer ; 58(3): 447-454, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34380844

RESUMO

Several studies have investigated the hypothesis of the efficacy of regional anesthesia (RA) techniques in preventing cancer recurrence when used perioperatively during oncological surgeries. Although theoretically, the association appears beneficial, the patient outcomes after cancer surgeries with or without RA were comparable, that is, the use of RA did not improve patient survival or prevent cancer recurrence after surgery. Another problem with this data is its retrospective nature which makes its interpretation difficult. Moreover, there are a lot of other confounding factors like comorbidities, tumor biology, nosocomial infections, duration of hospital stay, and baseline immunity, which is not comparable, and hence make standardization for a well-designed prospective study difficult. Return to intended oncologic therapy (RIOT) involves treatment in the form of radiation or chemotherapy which, if received on time after the planned oncosurgery, could provide a better chance of preventing cancer recurrence and improved survival. However, none of the retrospective studies have correlated cancer recurrence with delay in RIOT or not receiving RIOT as a cause of cancer recurrence. This paper discusses why even a well-designed, prospective trial could possibly never establish the efficacy of RA in preventing cancer recurrence and improving survival due to the complexities involved in a patient undergoing oncosurgery.


Assuntos
Anestesia por Condução/métodos , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias/tratamento farmacológico , Neoplasias/cirurgia , Período Perioperatório/métodos , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico
11.
Indian J Cancer ; 57(3): 234-238, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32769293

RESUMO

Dexmedetomidine is a centrally acting α2 adrenoreceptor agonist used in perioperative medicine due to its sedative, analgesic and sympatholytic properties. Recently animal data has pointed towards potential role of dexmedetomidine in promoting cancer recurrence and metastasis when used perioperatively especially after breast surgeries. This is because of presence of α2 adrenoreceptors in breast cancer tissue. We reviewed existing literature in which dexmedetomidine was used in cancer surgeries and investigated its role in recurrence and metastasis.


Assuntos
Dexmedetomidina/uso terapêutico , Hipnóticos e Sedativos/uso terapêutico , Neoplasias/tratamento farmacológico , Dexmedetomidina/farmacologia , Humanos , Hipnóticos e Sedativos/farmacologia , Neoplasias/cirurgia
12.
Retrovirology ; 6: 76, 2009 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-19674458

RESUMO

The development of novel techniques and systems to study human infectious diseases in both an in vitro and in vivo settings is always in high demand. Ideally, small animal models are the most efficient method of studying human afflictions. This is especially evident in the study of the human retroviruses, HIV-1 and HTLV-1, in that current simian animal models, though robust, are often expensive and difficult to maintain. Over the past two decades, the construction of humanized animal models through the transplantation and engraftment of human tissues or progenitor cells into immunocompromised mouse strains has allowed for the development of a reconstituted human tissue scaffold in a small animal system. The utilization of small animal models for retroviral studies required expansion of the early CB-17 scid/scid mouse resulting in animals demonstrating improved engraftment efficiency and infectivity. The implantation of uneducated human immune cells and associated tissue provided the basis for the SCID-hu Thy/Liv and hu-PBL-SCID models. Engraftment efficiency of these tissues was further improved through the integration of the non-obese diabetic (NOD) mutation leading to the creation of NODSCID, NOD/Shi-scid IL2rgamma-/-, and NOD/SCID beta2-microglobulinnull animals. Further efforts at minimizing the response of the innate murine immune system produced the Rag2-/-gammac-/- model which marked an important advancement in the use of human CD34+ hematopoietic stem cells. Together, these animal models have revolutionized the investigation of retroviral infections in vivo.


Assuntos
Modelos Animais de Doenças , Infecções por Retroviridae , Animais , Proteínas de Ligação a DNA/deficiência , HIV-1/crescimento & desenvolvimento , Vírus Linfotrópico T Tipo 1 Humano/crescimento & desenvolvimento , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
13.
Retrovirology ; 6: 2, 2009 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-19144136

RESUMO

BACKGROUND: Cells derived from native rodents have limits at distinct steps of HIV replication. Rat primary CD4 T-cells, but not macrophages, display a profound transcriptional deficit that is ameliorated by transient trans-complementation with the human Tat-interacting protein Cyclin T1 (hCycT1). RESULTS: Here, we generated transgenic rats that selectively express hCycT1 in CD4 T-cells and macrophages. hCycT1 expression in rat T-cells boosted early HIV gene expression to levels approaching those in infected primary human T-cells. hCycT1 expression was necessary, but not sufficient, to enhance HIV transcription in T-cells from individual transgenic animals, indicating that endogenous cellular factors are critical co-regulators of HIV gene expression in rats. T-cells from hCD4/hCCR5/hCycT1-transgenic rats did not support productive infection of prototypic wild-type R5 HIV-1 strains ex vivo, suggesting one or more significant limitation in the late phase of the replication cycle in this primary rodent cell type. Remarkably, we identify a replication-competent HIV-1 GFP reporter strain (R7/3 YU-2 Env) that displays characteristics of a spreading, primarily cell-to-cell-mediated infection in primary T-cells from hCD4/hCCR5-transgenic rats. Moreover, the replication of this recombinant HIV-1 strain was significantly enhanced by hCycT1 transgenesis. The viral determinants of this so far unique replicative ability are currently unknown. CONCLUSION: Thus, hCycT1 expression is beneficial to de novo HIV infection in a transgenic rat model, but additional genetic manipulations of the host or virus are required to achieve full permissivity.


Assuntos
Linfócitos T CD4-Positivos/virologia , Ciclinas/metabolismo , HIV-1/fisiologia , Transcrição Gênica , Replicação Viral , Animais , Células Cultivadas , Ciclina T , HIV-1/crescimento & desenvolvimento , Humanos , Macrófagos/virologia , Ratos , Ratos Transgênicos
14.
AIDS Res Ther ; 6: 23, 2009 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-19891783

RESUMO

BACKGROUND: Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are an important category of drugs for both chemotherapy and prevention of human immunodeficiency virus type 1 (HIV-1) infection. However, current non-human primate (NHP) models utilizing simian immunodeficiency virus (SIV) or commonly used chimeric SHIV (SIV expressing HIV-1 envelope) are inadequate due to the insensitivity to NNRTIs. To develop a NHP model for evaluation of NNRTI compounds, we characterized a RT-SHIV virus that was assembled by replacing the SIV mac239 reverse transcriptase (RT) with that of HIV-1HXB2. Since RT-SHIV exhibited in vitro characteristics of high infectivity, CCR5-usage, and sensitivity to HIV-1 specific NNRTIs, this virus was thought to be suitable for mucosal transmission and then was used to carry out a vaginal transmission study in pigtail macaques (Macaca nemestrina). RESULTS: RT-SHIV exhibited in vitro characteristics of an infectious CCR5-tropic chimeric virus. This virus was not only highly sensitive to HIV-1 RT specific NNRTIs; its replication was also inhibited by a variety of NRTIs and protease inhibitors. For in vivo vaginal transmission studies, macaques were either pretreated with a single dose of DMPA (depot medroxyprogesterone acetate) or left untreated before intravaginal inoculation with 500 or 1,000 TCID50 of RT-SHIV. All macaques became systemically infected by 2 or 3 weeks post-inoculation exhibiting persistent high viremia, marked CD4+T cell depletion, and antiviral antibody response. DMPA-pretreated macaques showed a higher mean plasma viral load after the acute infection stage, highly variable antiviral antibody response, and a higher incidence of AIDS-like disease as compared with macaques without DMPA pretreatment. CONCLUSION: This chimeric RT-SHIV has exhibited productive replication in both macaque and human PBMCs, predominantly CCR5-coreceptor usage for viral entry, and sensitivity to NNRTIs as well as other anti-HIV compounds. This study demonstrates rapid systemic infection in macaques following intravaginal exposure to RT-SHIV. This RT-SHIV/macaque model could be useful for evaluation of NNRTI-based therapies, microbicides, or other preventive strategies.

15.
Rambam Maimonides Med J ; 10(1)2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30304665

RESUMO

BACKGROUND AND AIMS: Multimodal analgesia comprising opioid, paracetamol, and non-steroidal anti-inflammatory drugs is used for managing postoperative surgical pain after ileostomy closure (IC). We investigated the efficacy of unilateral dual transversus abdominis plane (TAP) block to reduce morphine consumption in the first 24 hours along with a reduction in visual analogue score for pain and in postoperative nausea/vomiting. METHODS: This was a single-center, investigator-initiated, prospective, parallel-group, placebo-controlled randomized study involving patients undergoing IC under general anesthesia. We recruited 55 patients in two groups: 28 in a TAP group and 27 in a placebo group. The TAP group patients received 30 mL of 0.375% bupivacaine: 15 mL by a posterior TAP approach and 15 mL by a subcostal approach using ultrasonography. Patients in the placebo group received 30 mL normal saline (placebo) using the same approaches. Blocks were administered at the end of surgery before extubation. To monitor for the primary outcome-24-hour morphine consumption for both groups-patients were transferred to a high-dependency unit. The secondary outcome was to compare postoperative nausea/vomiting in both groups. RESULTS: The demographic data, gender distribution, ASA physical status, duration of surgery, and time of first morphine dose was comparable in both groups. The 24-hour morphine consumption was 3.29±2.78 mg and 9.23±2.94 mg for the TAP and placebo groups, respectively, which was statistically significant (P=0.001). CONCLUSION: Dual TAP block reduces opioid consumption in the first 24 hours after an IC and can facilitate early recovery with less adverse effects seen than with opioids and NSAIDs.

16.
Expert Rev Proteomics ; 5(3): 507-28, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18532916

RESUMO

Overall changes in the host cellular proteome upon retroviral infection intensify from the initial entry of the virus to the incorporation of viral DNA into the host genome, and finally to the consistent latent state of infection. The host cell reacts to both the entry of viral elements and the manipulation of host cellular machinery, resulting in a cascade of signaling events and pathway activation. Cell type- and tissue-specific responses are also characteristic of infection and can be classified based on the differential expression of genes and proteins between normal and disease states. The characterization of differentially expressed proteins upon infection is also critical in identifying potential biomarkers within infected bodily fluids. Biomarkers can be used to monitor the progression of infection, track the effectiveness of specific treatments and characterize the mechanisms of disease pathogenesis. Standard proteomic approaches have been applied to monitor the changes in global protein expression and localization in infected cells, tissues and fluids. Here we report on recent investigations into the characterization of proteomes in response to retroviral infection.


Assuntos
Sobrevivência Celular , Proteômica , Retroviridae/metabolismo , Proteínas Virais/metabolismo , Replicação Viral , Humanos , Retroviridae/fisiologia
17.
Anesth Essays Res ; 12(2): 552-554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29962633

RESUMO

BACKGROUND: Peri-operative incentive spirometry (IS) helps in improving pulmonary function, facilitates sputum clearance and prevents unwanted postoperative pulmonary complications after major abdominal and thoracic surgery. In our hospital, all patients are instructed to practice IS before abdominal and thoracic surgeries so that they can perform it in the postoperative period effectively. However, many patients do not follow our advice. A few unfortunate patients land up with pulmonary complications as it becomes difficult to train them after surgery. AIMS: To determine the compliance rate of patients who were instructed to perform incentive spirometry preoperatively. STUDY DESIGN AND SETTINGS: Observational, single arm study in a single speciality centre. MATERIALS AND METHODS: After approval from hospital ethics committee the study was registered with Clinical Trials Registry of India (CTRI). 100 patients posted for major abdominal or thoracic cancer surgery were enrolled in the study. They were instructed to perform incentive spirometry(IS) in front of relatives, an information leaflet was provided to them and the spirometry effort was noted in 'ml'. The effort was crossed checked on the day of surgery. Patients performing IS correctly with effort more or equal to that noted earlier were labelled as compliant. Others were labelled as non-compliant. The reason of non-compliance was to be determined using a questionnaire meant for patient and the accompanying family member. RESULTS: Out of 100, 26 patients were found to be non-compliant out of which 10 were males and 16 were female patients. 15 patients did not understand the instructions properly, 8 patients did not get enough time to practice, family members of 10 patients could not help the patient in performing and understanding IS, family members of 8 patients did not have adequate time for the patient. CONCLUSION: A non-compliance rate of 26% could be because patients and family members did not understand the seriousness of preoperative IS in spite of explaining and giving an information leaflet. The surgeries planned were major ones which require arrangement of finances, abstinence from work and other social issues like not having anybody at home with other family members, location of hospital far from the place they live. Involving respiratory therapist and nursing staff early during pre-anaesthesia check up could help in better understanding of the patient and family regarding benefits of IS.

18.
Am J Med Sci ; 350(3): 191-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26263235

RESUMO

BACKGROUND: Infectious disease (ID) clinicians and multidisciplinary teams may have a beneficial impact on patient outcomes. This study was conducted to determine the impact of dedicated ID team rounding in an adult noncardiac intensive care unit (ICU) on antimicrobial costs, length of stay and mortality. METHODS: The authors instituted dedicated ICU ID team rounds at a large tertiary care hospital ICU ("intervention"), with the ID team conducting rounds in the ICU every weekday. The authors compared the cost of antimicrobial agents, total hospital and ICU length of stay and inpatient mortality for the 6-month period before and after institution of these rounds between those seen versus those not seen by the ID team. RESULTS: Among 386 patients analyzed, 206 were admitted in the preintervention and 180 in the postintervention period. Among those seen by the ID team, there was an 18% decrease in total antimicrobial cost (P < 0.0001), 40% decrease in ICU length of stay (P = 0.1), 33% decrease in overall hospital length of stay (P = 0.03) and 34% decrease in mortality (0.04) from preintervention to postintervention period. Among those not seen by ID, there was a 39% decrease in cost among those not seen by ID (P < 0.0001), but length of ICU or hospital stay and mortality were not significantly different. CONCLUSIONS: Institution of dedicated ID team rounding in the ICU leads to substantial decreases in antimicrobial costs, hospital length of stay and inpatient mortality among those patients seen by the team.


Assuntos
Anti-Infecciosos/economia , Doenças Transmissíveis , Cuidados Críticos/métodos , Mortalidade Hospitalar/tendências , Tempo de Internação/estatística & dados numéricos , Equipe de Assistência ao Paciente/estatística & dados numéricos , Adulto , Idoso , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/uso terapêutico , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/mortalidade , Custos de Medicamentos , Feminino , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente/organização & administração , Centros de Atenção Terciária/estatística & dados numéricos , Emirados Árabes Unidos
19.
Virology ; 485: 1-15, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26184775

RESUMO

The highly active antiretroviral therapy reduces HIV-1 RNA in plasma to undetectable levels. However, the virus continues to persist in the long-lived resting CD4(+) T cells, macrophages and astrocytes which form a viral reservoir in infected individuals. Reactivation of viral transcription is critical since the host immune response in combination with antiretroviral therapy may eradicate the virus. Using the chronically HIV-1 infected T lymphoblastoid and monocytic cell lines, primary quiescent CD4(+) T cells and humanized mice infected with dual-tropic HIV-1 89.6, we examined the effect of various X-ray irradiation (IR) doses (used for HIV-related lymphoma treatment and lower doses) on HIV-1 transcription and viability of infected cells. Treatment of both T cells and monocytes with IR, a well-defined stress signal, led to increase of HIV-1 transcription, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter. This correlated with the increased GFP signal and elevated level of intracellular HIV-1 RNA in the IR-treated quiescent CD4(+) T cells infected with GFP-encoding HIV-1. Exposition of latently HIV-1infected monocytes treated with PKC agonist bryostatin 1 to IR enhanced transcription activation effect of this latency-reversing agent. Increased HIV-1 replication after IR correlated with higher cell death: the level of phosphorylated Ser46 in p53, responsible for apoptosis induction, was markedly higher in the HIV-1 infected cells following IR treatment. Exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma, lung and brain tissues. Collectively, these data point to the use of low to moderate dose of IR alone or in combination with HIV-1 transcription activators as a potential application for the "Shock and Kill" strategy for latently HIV-1 infected cells.


Assuntos
Apoptose/efeitos da radiação , Raios gama/uso terapêutico , Infecções por HIV/radioterapia , HIV-1/efeitos da radiação , Transcrição Gênica/efeitos da radiação , Animais , Fármacos Anti-HIV/farmacologia , Briostatinas/farmacologia , Linfócitos T CD4-Positivos , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/fisiologia , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Humanos , Masculino , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Monócitos , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA Viral/agonistas , RNA Viral/genética , RNA Viral/metabolismo , Proteínas Repressoras/agonistas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ativação Viral/efeitos da radiação , Replicação Viral/efeitos da radiação
20.
AIDS Res Hum Retroviruses ; 18(4): 259-67, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11860673

RESUMO

The goal of this study was to determine the importance of cellular factors for binding of HIV to cells. HIV primary isolates (PIs) produced in peripheral blood mononuclear cells (PBMCs) bound at relatively high levels to PBMCs but at low levels to cell lines, whereas T cell line-adapted (TCLA) virus produced in the H9 T cell line bound at high levels to both cell lines and PBMCs. Expression of CD4 in CD4-negative cells or blocking CD4 with antibody on CD4-positive cells did not affect virus binding. Blocking of gp120/gp41 with antibodies or a lack of expression of gp120/gp41 in virus particles also did not affect virus binding. However, the cell type from which virus was produced did affect virus binding. Thus, the binding pattern of TCLA virus shifted to that of a PI virus when produced in PBMCs. A PI binding pattern also occurred when a cloned TCLA virus (NL4-3) was produced in PBMCs, indicating that the virus-producing cell type has more of an effect on virus binding than the virus strain. These experiments show that both the virus-producing cell and the target cell have a major influence on HIV binding and suggest that host cell factors incorporated into virions are important for virus binding.


Assuntos
HIV-1/fisiologia , Fusão de Membrana , Linhagem Celular , Proteína gp120 do Envelope de HIV/metabolismo , Proteína gp41 do Envelope de HIV/metabolismo , Humanos
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