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1.
J Virol ; 97(3): e0002923, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36856444

RESUMO

The major immediate early enhancer and promoter (MIEP) of human cytomegalovirus (HCMV) drives the transcription of the immediate early one (IE1) and IE2 genes, whose encoded proteins stimulate productive, lytic replication. The MIEP is activated by the virally encoded and tegument-delivered pp71 protein at the start of de novo lytic infections of fully differentiated cells. Conversely, the MIEP is silenced at the start of de novo latent infections within incompletely differentiated myeloid cells in part because tegument-delivered pp71 is sequestered in the cytoplasm in these cells, but also by viral factors that repress transcription from this locus, including the UL138 protein. During both modes of infection, MIEP activity can be increased by the histone deacetylase inhibitor valproic acid (VPA); however, UL138 inhibits the VPA-responsiveness of the MIEP. Here, we show that two families of cellular transcription factors, NF-κB and cAMP response element-binding protein (CREB), together control the VPA-mediated activation and UL138-mediated repression of the HCMV MIEP. IMPORTANCE Artificial regulation of the HCMV MIEP, either activation or repression, is an attractive potential means to target the latent reservoirs of virus for which there is currently no available intervention. The MIEP could be repressed to prevent latency reactivation or induced to drive the virus into the lytic stage that is visible to the immune system and inhibited by multiple small-molecule antiviral drugs. Understanding how the MIEP is regulated is a critical part of designing and implementing either strategy. Our revelation here that NF-κB and CREB control the responsiveness of the MIEP to the viral UL138 protein and the FDA-approved drug VPA could help in the formulation and execution of promoter regulatory strategies against latent HCMV.


Assuntos
Citomegalovirus , NF-kappa B , Humanos , AMP Cíclico/metabolismo , Citomegalovirus/fisiologia , Regulação Viral da Expressão Gênica , NF-kappa B/genética , NF-kappa B/metabolismo , Elementos de Resposta , Ácido Valproico/farmacologia , Ácido Valproico/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
2.
IEEE Trans Med Robot Bionics ; 3(3): 762-772, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36970042

RESUMO

This paper presents a dual-arm suturing robot. We extend the Smart Tissue Autonomous Robot (STAR) with a second robot manipulator, whose purpose is to manage loose suture thread, a task that was previously executed by a human assistant. We also introduce novel near-infrared fluorescent (NIRF) sutures that are automatically segmented and delimit the boundaries of the suturing task. During ex-vivo experiments of porcine models, our results demonstrate that this new system is capable of outperforming human surgeons in all but one metric for the task of vaginal cuff closure (porcine model) and is more consistent in every aspect of the task. We also present results to demonstrate that the system can perform a vaginal cuff closure during an in-vivo experiment (porcine model).

3.
Hum Mol Genet ; 29(7): 1083-1095, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31628488

RESUMO

Fanconi anemia (FA) is a chromosome instability syndrome characterized by increased cancer predisposition. Specifically, the FA pathway functions to protect genome stability during DNA replication. The central FA pathway protein, FANCD2, locates to stalled replication forks and recruits homologous recombination (HR) factors such as CtBP interacting protein (CtIP) to promote replication fork restart while suppressing new origin firing. Here, we identify alpha-thalassemia retardation syndrome X-linked (ATRX) as a novel physical and functional interaction partner of FANCD2. ATRX is a chromatin remodeler that forms a complex with Death domain-associated protein 6 (DAXX) to deposit the histone variant H3.3 into specific genomic regions. Intriguingly, ATRX was recently implicated in replication fork recovery; however, the underlying mechanism(s) remained incompletely understood. Our findings demonstrate that ATRX forms a constitutive protein complex with FANCD2 and protects FANCD2 from proteasomal degradation. ATRX and FANCD2 localize to stalled replication forks where they cooperate to recruit CtIP and promote MRE11 exonuclease-dependent fork restart while suppressing the firing of new replication origins. Remarkably, replication restart requires the concerted histone H3 chaperone activities of ATRX/DAXX and FANCD2, demonstrating that coordinated histone H3 variant deposition is a crucial event during the reinitiation of replicative DNA synthesis. Lastly, ATRX also cooperates with FANCD2 to promote the HR-dependent repair of directly induced DNA double-stranded breaks. We propose that ATRX is a novel functional partner of FANCD2 to promote histone deposition-dependent HR mechanisms in S-phase.


Assuntos
Proteínas Correpressoras/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Anemia de Fanconi/genética , Chaperonas Moleculares/genética , Proteína Nuclear Ligada ao X/genética , Linhagem Celular , Cromatina/genética , Montagem e Desmontagem da Cromatina/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Replicação do DNA/genética , Anemia de Fanconi/patologia , Técnicas de Inativação de Genes/métodos , Histonas/genética , Humanos , Proteína Homóloga a MRE11/genética , Rad51 Recombinase/genética , Reparo de DNA por Recombinação/genética , Transdução de Sinais/genética
4.
Mar Environ Res ; 149: 137-147, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31204014

RESUMO

Responses of marine ectotherms to variable environmental temperature often entails maintanence of cellular homeostasis and physiological function through temperature compensation and physiological changes. We investigated the physiological response to thermal stress by examining proteomic changes in the marine kelp forest gastropod and emerging fisheries species Kellet's whelk (Kelletia kelletii) across a naturally-existing thermal gradient that ranges from a warmer-water site inside the species' native range and extends to the northern, cold-water edge of the range. We hypothesized that abundance of cellular stress response and energy metabolism proteins would increase with decreasing temperature in support of cold-compensation. Our exploratory proteomic analysis of whelk gill tissue (N = 6 whelks) from each of the four California Channel Island sites revealed protein abundance changes related to the cytoskeleton, energy metabolism/oxidative stress, and cell signaling. The changes did not correlate consistently with temperature. Nonetheless, whelks from the coldest island site showed increased abundance of energy metabolism and oxidative stress proteins, possibly suggesting oxidative damage of lipid membranes that is ameliorated by antioxidants and may aid in their cold stress response. Similarly, our exploratory analysis revealed abundances of cell signaling proteins that were higher at the coldest site compared to the warmest site, possibly indicating an importance for cell signaling regulation in relatively cooler environments. This study provides protein targets for future studies related to thermal effects in marine animals and may contribute to understanding the physiological response of marine organisms to future ocean conditions.


Assuntos
Adaptação Fisiológica/fisiologia , Mudança Climática , Gastrópodes/metabolismo , Proteoma/metabolismo , Animais , Organismos Aquáticos/metabolismo , California , Cistationina gama-Liase/metabolismo , Proteínas do Citoesqueleto/metabolismo , Metabolismo Energético , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Aquecimento Global , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/fisiologia , Temperatura
5.
BMC Musculoskelet Disord ; 19(1): 67, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499666

RESUMO

The utility of nanotechnology in medicine, specifically within the field of orthopedics, is a topic of extensive research. Our review provides a unique comprehensive overview of the current and potential future uses of nanotechnology with respect to orthopedic sub-specialties. Nanotechnology offers an immense assortment of novel applications, most notably the use of nanomaterials as scaffolds to induce a more favorable interaction between orthopedic implants and native bone. Nanotechnology has the capability to revolutionize the diagnostics and treatment of orthopedic surgery, however the long-term health effects of nanomaterials are poorly understood and extensive research is needed regarding clinical safety.


Assuntos
Nanoestruturas/administração & dosagem , Nanotecnologia/métodos , Procedimentos Ortopédicos/métodos , Ortopedia/métodos , Doenças Ósseas/patologia , Doenças Ósseas/terapia , Humanos , Nanotecnologia/tendências , Procedimentos Ortopédicos/tendências , Ortopedia/tendências , Próteses e Implantes/tendências
6.
Water Res ; 45(8): 2607-15, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21420710

RESUMO

Plastic piping made of polyvinyl chloride (PVC), and chlorinated PVC (CPVC), is being increasingly used for drinking water distribution lines. Given the formulation of the material from vinyl chloride (VC), there has been concern that the VC (a confirmed human carcinogen) can leach from the plastic piping into drinking water. PVC/CPVC pipe reactors in the laboratory and tap samples collected from consumers homes (n = 15) revealed vinyl chloride accumulation in the tens of ng/L range after a few days and hundreds of ng/L after two years. While these levels did not exceed the EPA's maximum contaminant level (MCL) of 2 µg/L, many readings that simulated stagnation times in homes (overnight) exceeded the MCL-Goal of 0 µg/L. Considerable differences in VC levels were seen across different manufacturers, while aging and biofilm effects were generally small. Preliminary evidence suggests that VC may accumulate not only via chemical leaching from the plastic piping, but also as a disinfection byproduct (DBP) via a chlorine-dependent reaction. This is supported from studies with CPVC pipe reactors where chlorinated reactors accumulated more VC than dechlorinated reactors, copper pipe reactors that accumulated VC in chlorinated reactors and not in dechlorinated reactors, and field samples where VC levels were the same before and after flushing the lines where PVC/CPVC fittings were contributing. Free chlorine residual tests suggest that VC may be formed as a secondary, rather than primary, DBP. Further research and additional studies need to be conducted in order to elucidate reaction mechanisms and tease apart relative contributions of VC accumulation from PVC/CPVC piping and chlorine-dependent reactions.


Assuntos
Cloreto de Polivinila/química , Cloreto de Vinil/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Desinfetantes/análise , Monitoramento Ambiental , Água Doce/química , Abastecimento de Água/estatística & dados numéricos
7.
Artigo em Inglês | MEDLINE | ID: mdl-3406427

RESUMO

1. Ninety psychiatric inpatients with a DSM III diagnosis of schizophrenia, mania, or major depression were studied. 2. Upon admission/transfer to the Clinical Studies Unit, and prior to discharge, measurements of symptom severity (BPRS, Ham-D, Young's Mania Scale) and blood samples were obtained. 3. Erythrocytes from these paired (admission and discharge) blood samples were assayed for methionine adenosyltransferase (MAT) activity and phosphatidylcholine (PC) content. 4. Comparisons were made between the changes in MAT Vmax, or % PC, and changes in symptom severity. 5. For the majority of the patients (79.3% of the schizophrenics; 84.6% of the depressives; and 93.8% of the manics), clinical improvement was associated with a "normalization" of enzyme activity. The association between changes in % PC and clinical response did not achieve significant correlation.


Assuntos
Transtorno Bipolar/enzimologia , Transtorno Depressivo/enzimologia , Eritrócitos/enzimologia , Metionina Adenosiltransferase/sangue , Esquizofrenia/enzimologia , Transferases/sangue , Transtorno Bipolar/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Humanos , Metionina/farmacocinética , Escalas de Graduação Psiquiátrica , Psicotrópicos/uso terapêutico , S-Adenosilmetionina/farmacocinética , Esquizofrenia/tratamento farmacológico
8.
Biol Psychiatry ; 21(14): 1391-8, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3790625

RESUMO

Two independent lines of inquiry have implicated some disturbance of one-carbon cycle metabolism in affective disorders. Folic acid deficiency commonly leads to depression, and S-adenosylmethionine has been reported to have antidepressant properties. Methionine adenosyltransferase has been reported to be underactive in depression and schizophrenia and overactive in mania. This study reports the effects on erythrocyte methionine adenosyltransferase (MAT) kinetics (Vmax) of a 2-week treatment in a population of patients housed on a psychiatric research ward. The drug-free schizophrenic patients and depressives had, upon admission, low Vmax values, and the drug-free manic patients had high Vmax values on admission. After 2 weeks of appropriate treatment, the values for all three patient samples showed significant normalization (i.e., the levels rose in schizophrenics and depressives and fell in manics). We have further shown that pretreatment low levels of erythrocyte membrane phosphatidylcholine in depressives and high levels in manics show statistically significant normalization following 2 weeks of pharmacotherapy. The significance of these results is discussed.


Assuntos
Membrana Eritrocítica/análise , Lipídeos de Membrana/sangue , Metionina Adenosiltransferase/sangue , Transtornos Psicóticos/sangue , Transferases/sangue , Transtorno Bipolar/sangue , Transtorno Depressivo/sangue , Humanos , Cinética , Fosfolipídeos/sangue , Psicotrópicos/uso terapêutico , Esquizofrenia/sangue
9.
J Clin Psychopharmacol ; 6(3): 155-61, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2872235

RESUMO

Erythrocyte methionine adenosyltransferase (MAT) activity (Vmax) and phosphatidylcholine (PC) levels previously have been found increased in manic patients and decreased in depressive and schizophrenic patients. To evaluate whether these abnormalities were the result of medication effects, erythrocyte MAT activity (Vmax) was assayed for paired samples from 29 schizophrenic, 16 manic, and 12 depressive patients, an erythrocyte PC levels were obtained for paired samples from 13 schizophrenic, seven manic, and seven depressive patients. Patients were medication free for at least 3 weeks. Vmax was significantly increased in schizophrenic and depressive patients (p less than 0.01; p less than 0.01) and significantly decreased (p less than 0.01) in manic patients after 2 weeks of psychotropic medication. Similar trends were found in PC levels. The findings of those one-carbon metabolism tests following medication are generally opposite to those reported to be related to specific disorders and tend toward normalization. Moreover, in vitro preincubation of erythrocytes of three normal subjects with the most commonly used neuroleptics had no consistent effects of MAT Vmax. These findings confirm previous studies that showed similarities in one-carbon metabolism of schizophrenic and depressed patients as opposed to manic patients and suggest that medications tend to correct or minimize rather than induce such abnormalities.


Assuntos
Transtorno Bipolar/metabolismo , Transtorno Depressivo/metabolismo , Metionina Adenosiltransferase/sangue , Fosfatidilcolinas/sangue , Esquizofrenia/metabolismo , Transferases/sangue , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Eritrócitos/metabolismo , Humanos , Lítio/uso terapêutico , Metilação , Esquizofrenia/tratamento farmacológico
10.
J Affect Disord ; 9(3): 297-301, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2934462

RESUMO

Methionine adenosyltransferase (MAT) activity (Vmax) and the relative amount of phosphatidylcholine (% PC) were measured in erythrocytes of up to 30 DSM-III diagnosed manic, 17 unipolar depressed patients, and 28 normal controls. Manic subjects had significantly higher and depressed subjects significantly lower MAT Vmax than normals. The relative amount of PC was in the low range for the depressives, and in the high range for the manics. Depressive patients present, in these tests, similar abnormalities to those seen previously in schizophrenic patients. Clinical and diagnostic implications of these findings are discussed.


Assuntos
Transtorno Bipolar/enzimologia , Transtorno Depressivo/enzimologia , Ácido Fólico/sangue , Metionina Adenosiltransferase/sangue , Fosfatidilcolinas/sangue , S-Adenosilmetionina/sangue , Transferases/sangue , Eritrócitos/enzimologia , Humanos , Cinética , Esquizofrenia/enzimologia
11.
Am J Psychiatry ; 142(3): 356-8, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3970278

RESUMO

RBCs from two lithium-free manic patients displayed lower choline transport and higher choline concentrations and methionine S-adenosyltransferase activity than those of controls. Lithium therapy decreased RBC methionine S-adenosyltransferase activity to normal, decreased choline transport further, and increased choline concentrations further.


Assuntos
Transtorno Bipolar/sangue , Colina/análise , Eritrócitos/análise , Lítio/uso terapêutico , Metionina Adenosiltransferase/análise , Transferases/análise , Adulto , Transporte Biológico/efeitos dos fármacos , Transtorno Bipolar/tratamento farmacológico , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Humanos , Lítio/farmacologia , Masculino , Metionina Adenosiltransferase/metabolismo , Pessoa de Meia-Idade , Projetos Piloto
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