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1.
Lab Chip ; 20(1): 54-63, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31774415

RESUMO

The alarming dynamics of antibiotic-resistant infections calls for the development of rapid and point-of-care (POC) antibiotic susceptibility testing (AST) methods. Here, we demonstrated the first completely stand-alone microfluidic system that allowed the execution of digital enumeration of bacteria and digital antibiograms without any specialized microfluidic instrumentation. A four-chamber gravity-driven step emulsification device generated ∼2000 monodisperse 2 nanoliter droplets with a coefficient of variation of 8.9% of volumes for 95% of droplets within less than 10 minutes. The manual workload required for droplet generation was limited to the sample preparation, the deposition into the sample inlet of the chip and subsequent orientation of the chip vertically without an additional pumping system. The use of shallow chambers imposing a 2D droplet arrangement provided superior stability of the droplets against coalescence and minimized the leakage of the reporter viability dye between adjacent droplets during long-term culture. By using resazurin as an indicator of the growth of bacteria, we were also able to reduce the assay time to ∼5 hours compared to 20 hours using the standard culture-based test.

2.
ACS Appl Mater Interfaces ; 12(2): 2572-2580, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31860265

RESUMO

Recently, aluminum ion batteries (AIBs) have attracted great attention across the globe by virtue of their massive gravimetric and volumetric capacities in addition to their high abundance. Though carbon derivatives are excellent cathodes for AIBs, there is much room for further development. In this study, flexuous graphite (FG) was synthesized by a simple thermal shock treatment, and for the first time, an Al/FG battery was applied as a cathode for AIBs to reveal the real-time intercalation of AlCl4- into FG with high flexibility by using in-situ scanning electron microscope (SEM) measurements exclusively. Similarly, in-situ X-ray diffraction (XRD) and in-situ Raman techniques have been used to understand the anomalous electrochemical behavior of FG. It was found that FG adopts a unique integrated intercalation-adsorption mechanism where it follows an intercalation mechanism potential above 1.5 V and an adsorption mechanism potential below 1.5 V. This unique integrated intercalation-adsorption mechanism allows FG to exhibit superior properties, like high capacity (≥140 mAh/g), remarkable long-term stability (over 8000 cycles), excellent rate retention (93 mAh/g at 7.5 A/g), and extremely rapid charging and slow discharging.

3.
Eur J Med Chem ; 178: 544-551, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31212133

RESUMO

Nalbuphine, a partial agonist/antagonist opioid analgesic, is structurally related to morphine. It is equipotent to morphine and has no serious side effects. In the past few decades, studies focusing on morphine metabolism have indicated that one of its sugar-conjugated metabolites, morphine-6-glucuronide, exerts a higher analgesic effect than its parent drug. Considering that nalbuphine is a morphine analog that follows a similar metabolic scheme, nalbuphine glucuronides were synthesized in this study and their potential analgesic effects were assessed. Nalbuphine-3-glucuronide (N3G) and nalbuphine-6-glucuronide (N6G) were synthesized based on Schmidt's glycosylation with OPiv protections on the glycosyl donor. In a pharmacodynamic study, paw pressure and cold-ethanol tail-flick tests were conducted in rats to evaluate the analgesic response after intracisternal and intraperitoneal administrations of nalbuphine, N3G, or N6G. The antinociceptive response was evaluated for each compound by calculating the area under the curve and the duration spent at greater than 50% maximum possible analgesia. In conclusion, intracisternal administration of N6G exhibited a stronger analgesic response than nalbuphine in the pain tests after both cold and mechanical stimuli, but N3G had no obvious effect. Similar to that of morphine, the glucuronide metabolite of nalbuphine at the 6-O-position exerted at least three-fold higher antinociceptive potency and five-fold longer analgesic duration than nalbuphine.


Assuntos
Analgésicos Opioides/farmacologia , Limiar da Dor/efeitos dos fármacos , Dor/tratamento farmacológico , Analgésicos Opioides/síntese química , Analgésicos Opioides/química , Animais , Relação Dose-Resposta a Droga , Masculino , Estrutura Molecular , Medição da Dor , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
4.
Kaohsiung J Med Sci ; 35(1): 33-38, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30844148

RESUMO

Renal epithelioid angiomyolipoma (eAML) is considered a malignant variant of angiomyolipoma (AML). From 2001 to 2016, a total of 570 patients were diagnosed with renal AML in Linko Chang Gung Memorial Hospital, Taiwan, including 23 cases of renal eAML. All 23 eAML cases were made up of at least 10% of epithelioid cells histologically. Three of these cases were found with multiple tumors. Two cases developed distant metastasis: one had mediastinal lymph nodes and bilateral lung metastasis; the other one had tumor recurrence over liver and retroperitoneum 1 year after radical nephrectomy. They were then divided into invasive (n = 5) and noninvasive (n = 18) groups according to their clinical behavior. The invasive group showed more severe nuclear atypia and higher rates in tumor necrosis. There was statistically no significance in relation to a patient's age, tumor size, and mitotic count between two groups. After conducting a series of studies, we suggest treating eAML with the guideline of renal cell carcinoma.


Assuntos
Angiomiolipoma/patologia , Células Epitelioides/patologia , Rim/patologia , Adulto , Angiomiolipoma/diagnóstico por imagem , Feminino , Humanos , Rim/diagnóstico por imagem , Masculino , Invasividade Neoplásica , Tomografia Computadorizada por Raios X
5.
J Formos Med Assoc ; 118(1 Pt 1): 162-169, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29549981

RESUMO

OBJECTIVES: To analyze and present the demography, clinical behavior, especially the risk factors of tumor hemorrhage and management of sporadic angiomyolipoma (SAML), tuberous sclerosis complex associated angiomyolipoma (TSCAML) and epithelioid angiomyolipoma (EAML) in our institution. METHODS: A retrospective study of 587 patients who were diagnosed with renal angiomyolipoma in our institution between January 2000 and May 2015 was done. The AMLs were diagnosed by ultrasonography, CT, or MRI. EAML was confirmed by histopathology. Medical records and follow-up results were analyzed using the SPSS version 22 software. RESULTS: Out of 587 cases of renal AMLs, 87.4% were SAMLs, 8.7% were TSCAMLs and 3.9% were EAMLs. Most of the AML patients were asymptomatic. The most common presenting symptoms included flank pain and abdominal pain. The median tumor size of SAML, TSCAML, EAML were 4.7, 2.7, 10.5 cm respectively. Approximately half of SAMLs were conservatively treated, almost all TSCAMLs were treated conservatively, while all EAMLs were surgically treated. The median tumor size of hemorrhagic SAML cases was 8 cm versus non-hemorrhagic cases of 4.1 cm. The optimal cut-off point on the ROC curve for predicting SAML tumor hemorrhage was 7.35 cm. CONCLUSION: A larger tumor size, younger patient's age and higher BMI value correlated with a higher risk of tumor hemorrhage. For tumor sizes less than 7.35 cm, we recommend active surveillance or TAE for hemorrhage prevention. We also suggest that surgical management should be considered for patients with tumors larger than 7.35 cm, symptomatic and progressive AML, or suspicious EAML.


Assuntos
Angiomiolipoma/classificação , Angiomiolipoma/terapia , Neoplasias Renais/classificação , Neoplasias Renais/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiomiolipoma/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Embolização Terapêutica , Feminino , Hemorragia/epidemiologia , Hemorragia/terapia , Humanos , Lactente , Rim/diagnóstico por imagem , Rim/patologia , Neoplasias Renais/patologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Taiwan , Tomografia Computadorizada por Raios X , Esclerose Tuberosa/complicações , Ultrassonografia , Adulto Jovem
6.
Front Immunol ; 9: 2860, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564245

RESUMO

In the battle between a virus and its host, innate immunity serves as the first line of defense protecting the host against pathogens. The antiviral actions start with the recognition of pathogen-associated molecular patterns derived from the virus, then ultimately turning on particular transcription factors to generate antiviral interferons (IFNs) or proinflammatory cytokines via fine-tuned signaling cascades. With dengue virus (DENV) infection, its viral RNA is recognized by the host RNA sensors, mainly retinoic acid inducible gene-I (RIG-I)-like receptors (RLRs) and toll-like receptors. DENV infection also activates the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING)-mediated DNA-sensing pathway despite the absence of a DNA stage in the DENV lifecycle. In the last decade, DENV has been considered a weak IFN-inducing pathogen with the evidence that DENV has evolved multiple strategies antagonizing the host IFN system. DENV passively escapes from innate immunity surveillance and also actively subverts the innate immune system at multiple steps. DENV targets both RNA-triggered RLR-mitochondrial antiviral signaling protein (RLR-MAVS) and DNA-triggered cGAS-STING signaling to reduce IFN production in infected cells. It also blocks IFN action by inhibiting IFN regulatory factor- and signal transducer and activator of transcription-mediated signaling. This review explores the current understanding of how DENV escapes the control of the innate immune system by modifying viral RNA and viral protein and by post-translational modification of cellular factors. The roles of the DNA-sensing pathway in DENV infection, and how mitochondrial dynamics participates in innate immunity are also discussed.


Assuntos
Vírus da Dengue/imunologia , Dengue/imunologia , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune , Imunidade Inata , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Dengue/virologia , Vírus da Dengue/genética , Humanos , Interferons/imunologia , Interferons/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/imunologia , Nucleotidiltransferases/metabolismo , Processamento de Proteína Pós-Traducional/imunologia , RNA Viral/metabolismo , Transdução de Sinais/imunologia , Receptores Toll-Like/imunologia , Receptores Toll-Like/metabolismo , Proteínas Virais/imunologia , Proteínas Virais/metabolismo
7.
Nanoscale Res Lett ; 13(1): 140, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29740717

RESUMO

In this study, the perovskite layers were prepared by two-step wet process with different CH3NH3I (MAI) concentrations. The cell structure was glass/FTO/TiO2-mesoporous/CH3NH3PbI3 (MAPbI3)/spiro-OMeTAD/Ag. The MAPbI3 perovskite films were prepared using high and low MAI concentrations in a two-step process. The perovskite films were optimized at different spin coating speed and different annealing temperatures to enhance the power conversion efficiency (PCE) of perovskite solar cells. The PCE of the resulting device based on the different perovskite morphologies was discussed. The PCE of the best cell was up to 17.42%, open circuit voltage of 0.97 V, short current density of 24.06 mA/cm2, and fill factor of 0.747.

8.
BMC Cancer ; 17(1): 277, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28420331

RESUMO

BACKGROUND: Arsenic is a widely distributed metalloid compound that has biphasic effects on cultured cells. In large doses, arsenic can be toxic enough to trigger cell death. In smaller amounts, non-toxic doses may promote cell proliferation and induces carcinogenesis. Aberration of chromosome is frequently detected in epithelial cells and lymphocytes of individuals from arsenic contaminated areas. Overexpression of Aurora-A, a mitotic kinase, results in chromosomal instability and cell transformation. We have reported that low concentration (≦1 µM) of arsenic treatment increases Aurora-A expression in immortalized bladder urothelial E7 cells. However, how arsenic induces carcinogenesis through Aurora-A activation remaining unclear. METHODS: Bromodeoxyuridine (BrdU) staining, MTT assay, and flow cytometry assay were conducted to determine cell proliferation. Messenger RNA and protein expression levels of Aurora-A were detected by reverse transcriptional-PCR and Western blotting, respectively. Centrosome of cells was observed by immunofluorescent staining. The transcription factor of Aurora-A was investigated by promoter activity, chromosome immunoprecipitation (ChIP), and small interfering RNA (shRNA) assays. Mouse model was utilized to confirm the relationship between arsenic and Aurora-A. RESULTS: We reveal that low dosage of arsenic treatment increased cell proliferation is associated with accumulated cell population at S phase. We also detected increased Aurora-A expression at mRNA and protein levels in immortalized bladder urothelial E7 cells exposed to low doses of arsenic. Arsenic-treated cells displayed increased multiple centrosome which is resulted from overexpressed Aurora-A. Furthermore, the transcription factor, E2F1, is responsible for Aurora-A overexpression after arsenic treatment. We further disclosed that Aurora-A expression and cell proliferation were increased in bladder and uterus tissues of the BALB/c mice after long-term arsenic (1 mg/L) exposure for 2 months. CONCLUSION: We reveal that low dose of arsenic induced cell proliferation is through Aurora-A overexpression, which is transcriptionally regulated by E2F1 both in vitro and in vivo. Our findings disclose a new possibility that arsenic at low concentration activates Aurora-A to induce carcinogenesis.


Assuntos
Arsênico/toxicidade , Aurora Quinase A/biossíntese , Carcinoma de Células de Transição/enzimologia , Fator de Transcrição E2F1/metabolismo , Neoplasias da Bexiga Urinária/enzimologia , Animais , Western Blotting , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina , Citometria de Fluxo , Imunofluorescência , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Neurovirol ; 22(2): 170-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26407716

RESUMO

Neurocognitive (NC) complications continue to afflict a substantial proportion of HIV-infected people taking effective antiretroviral therapy (ART). One contributing mechanism for this is antiretroviral neurotoxicity. Efavirenz (EFV) is associated with short-term central nervous system (CNS) toxicity, but less is known about its long-term effects. Our objective was to compare NC functioning with long-term use of EFV to that of a comparator, lopinavir-ritonavir (LPV/r), in a cohort of well-characterized adults. Four hundred forty-five patients were selected from the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) cohort based on their use of either EFV (n = 272, mean duration 17.9 months) or LPV/r (n = 173, mean duration 16.4 months) and the lack of severe NC comorbidities. All patients had undergone standardized comprehensive NC testing. Univariable and multivariable analyses to predict NC outcomes were performed. Compared with LPV/r users, EFV users were more likely to be taking their first ART regimen (p < 0.001), were less likely to have AIDS (p < 0.001) or hepatitis C virus (HCV) coinfection (p < 0.05), had higher CD4+ T cell nadirs (p < 0.001), had lower peak (p < 0.001) and current (p < 0.001) plasma HIV RNA levels, and were less likely to have detectable HIV RNA in cerebrospinal fluid (CSF) (p < 0.001). Overall, EFV users had worse speed of information processing (p = 0.04), verbal fluency (p = 0.03), and working memory (p = 0.03). An interaction with HCV serostatus was present: Overall among HCV seronegatives (n = 329), EFV users performed poorly, whereas among HCV seropositives (n = 116), LPV/r users had overall worse performance. In the subgroup with undetectable plasma HIV RNA (n = 269), EFV users had worse speed of information processing (p = 0.02) and executive functioning (p = 0.03). Substantial differences exist between EFV and LPV/r users in this observational cohort, possibly because of channeling by clinicians who may have prescribed LPV/r to more severely ill patients or as second-line therapy. Despite these differences, EFV users had worse functioning in several cognitive abilities. A potentially important interaction was identified that could indicate that the NC consequences of specific antiretroviral drugs may differ based on HCV coinfection. The complexity of these data is substantial, and findings would best be confirmed in a randomized clinical trial.


Assuntos
Benzoxazinas/efeitos adversos , Disfunção Cognitiva/fisiopatologia , Função Executiva/efeitos dos fármacos , Infecções por HIV/fisiopatologia , Hepatite C/fisiopatologia , Memória/efeitos dos fármacos , Aprendizagem Verbal/efeitos dos fármacos , Adulto , Fármacos Anti-HIV/uso terapêutico , Benzoxazinas/administração & dosagem , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/imunologia , Coinfecção , Quimioterapia Combinada , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/fisiologia , Hepacivirus/fisiologia , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepatite C/imunologia , Humanos , Lopinavir/uso terapêutico , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Ritonavir/uso terapêutico
10.
PLoS One ; 10(10): e0140747, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465338

RESUMO

Fibroblasts have been extensively used as a model to study cellular senescence. The purpose of this study was to investigate whether the human foreskin fibroblast aging process could be regulated by using the biomaterial chitosan. Fibroblasts cultured on commercial tissue culture polystyrene (TCPS) entered senescence after 55-60 population doublings (PDs), and were accompanied by larger cell shape, higher senescence-associated ß-galactosidase (SA ß-gal) activity, lower proliferation capacity, and upregulation of senescence-associated molecular markers p21, p53, retinoblastoma (pRB), and p16. Before senescence was reached, PD48 cells were collected from TCPS and seeded on chitosan for three days (PD48-Cd3) to form multicellular spheroids. The protein expression of senescence-associated secretory phenotypes (SASPs) and senescence-associated molecular markers of these cells in PD48-Cd3 spheroids were downregulated significantly. Following chitosan treatment, fibroblasts reseeded on TCPS showed lower SA ß-gal activity, increased cellular motility, and a higher proliferation ability of 70-75 PDs. These phenotypic changes were not accompanied by colonies forming in soft agar and a continuous decrease in the senescence-associated proteins p53 and pRB which act as a barrier to tumorigenesis. These results demonstrate that chitosan treatment could delay the induction of senescence which may be useful and safe for future tissue engineering applications.


Assuntos
Senescência Celular/efeitos dos fármacos , Quitosana/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Prepúcio do Pênis/citologia , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Senescência Celular/genética , Prepúcio do Pênis/metabolismo , Expressão Gênica , Humanos , Masculino
11.
PLoS One ; 10(3): e0120770, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25790110

RESUMO

Endothelial dysfunction contributes to the development of acute kidney injury (AKI) in animal models of ischemia reperfusion injury and sepsis. There are limited data on markers of endothelial dysfunction in human AKI. We hypothesized that Protein C (PC) and soluble thrombomodulin (sTM) levels could predict AKI. We conducted a multicenter prospective study in 80 patients to assess the relationship of PC and sTM levels to AKI, defined by the AKIN creatinine (AKI Scr) and urine output criteria (AKI UO). We measured marker levels for up to 10 days from intensive care unit admission. We used area under the curve (AUC) and time-dependent multivariable Cox proportional hazard model to predict AKI and logistic regression to predict mortality/non-renal recovery. Protein C and sTM were not different in patients with AKI UO only versus no AKI. On intensive care unit admission, as PC levels are usually lower with AKI Scr, the AUC to predict the absence of AKI was 0.63 (95%CI 0.44-0.78). The AUC using log10 sTM levels to predict AKI was 0.77 (95%CI 0.62-0.89), which predicted AKI Scr better than serum and urine neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C, urine kidney injury molecule-1 and liver-fatty acid-binding protein. In multivariable models, PC and urine NGAL levels independently predicted AKI (p=0.04 and 0.02) and PC levels independently predicted mortality/non-renal recovery (p=0.04). In our study, PC and sTM levels can predict AKI Scr but are not modified during AKI UO alone. PC levels could independently predict mortality/non-renal recovery. Additional larger studies are needed to define the relationship between markers of endothelial dysfunction and AKI.


Assuntos
Lesão Renal Aguda/sangue , Proteína C/metabolismo , Trombomodulina/sangue , Trombomodulina/química , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/mortalidade , Biomarcadores/sangue , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Solubilidade
12.
PLoS Pathog ; 11(3): e1004750, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25816318

RESUMO

Infection with Japanese encephalitis virus (JEV) can induce the expression of pro-inflammatory cytokines and cause acute encephalitis in humans. ß-oxidation breaks down fatty acids for ATP production in mitochondria, and impaired ß-oxidation can induce pro-inflammatory cytokine expression. To address the role of fatty-acid ß-oxidation in JEV infection, we measured the oxygen consumption rate of mock- and JEV-infected cells cultured with or without long chain fatty acid (LCFA) palmitate. Cells with JEV infection showed impaired LCFA ß-oxidation and increased interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) expression. JEV nonstructural protein 5 (NS5) interacted with hydroxyacyl-CoA dehydrogenase α and ß subunits, two components of the mitochondrial trifunctional protein (MTP) involved in LCFA ß-oxidation, and NS5 proteins were detected in mitochondria and co-localized with MTP. LCFA ß-oxidation was impaired and higher cytokines were induced in cells overexpressing NS5 protein as compared with control cells. Deletion and mutation studies showed that the N-terminus of NS5 was involved in the MTP association, and a single point mutation of NS5 residue 19 from methionine to alanine (NS5-M19A) reduced its binding ability with MTP. The recombinant JEV with NS5-M19A mutation (JEV-NS5-M19A) was less able to block LCFA ß-oxidation and induced lower levels of IL-6 and TNF-α than wild-type JEV. Moreover, mice challenged with JEV-NS5-M19A showed less neurovirulence and neuroinvasiveness. We identified a novel function of JEV NS5 in viral pathogenesis by impairing LCFA ß-oxidation and inducing cytokine expression by association with MTP.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/metabolismo , Encefalite Japonesa/metabolismo , Ácidos Graxos/metabolismo , Subunidade alfa da Proteína Mitocondrial Trifuncional/metabolismo , Subunidade beta da Proteína Mitocondrial Trifuncional/metabolismo , Proteínas não Estruturais Virais/metabolismo , Animais , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/genética , Ácidos Graxos/genética , Células HEK293 , Humanos , Camundongos , Subunidade alfa da Proteína Mitocondrial Trifuncional/genética , Subunidade beta da Proteína Mitocondrial Trifuncional/genética , Oxirredução , Mutação Puntual , Proteínas não Estruturais Virais/genética
13.
Neurology ; 84(3): 241-50, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25503616

RESUMO

OBJECTIVE: To investigate the effect of hepatitis C virus (HCV) on neurocognitive performance in chronically HIV-infected patients enrolled in the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study. METHODS: A total of 1,582 participants in CHARTER who were tested for HCV antibody underwent neurocognitive testing; serum HCV RNA was available for 346 seropositive patients. Neurocognitive performance was compared in 408 HCV-seropositive and 1,174 HCV-seronegative participants and in a subset of 160 seropositive and 707 seronegative participants without serious comorbid neurologic conditions that might impair neurocognitive performance, using linear regression and taking into account HIV-associated and demographic factors (including IV drug use) and liver function. RESULTS: Neurocognitive performance characterized by global deficit scores and the proportion of individuals who were impaired were the same in the HCV-seropositive and HCV-seronegative groups. In univariable analyses in the entire sample, only verbal domain scores showed small statistically different superior performance in the HCV+ group that was not evident in multivariable analysis. In the subgroup without significant comorbidities, scores in all 7 domains of neurocognitive functioning did not differ by HCV serostatus. Among the HCV-seropositive participants, there was no association between neurocognitive performance and serum HCV RNA concentration. CONCLUSION: In HIV-infected patients, HCV coinfection does not contribute to neurocognitive impairment, at least in the absence of substantial HCV-associated liver damage, which was not evident in our cohort.


Assuntos
Transtornos Cognitivos/etiologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepatite C/complicações , Hepatite C/epidemiologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/patologia , Estudos de Coortes , Feminino , HIV/genética , HIV/imunologia , HIV/patogenicidade , Infecções por HIV/patologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Testes Sorológicos , Estados Unidos , Carga Viral
14.
J Immunol ; 193(8): 4159-68, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25225661

RESUMO

Human MCP-1-induced protein 1 (MCPIP1, also known as ZC3H12A and Regnase-1) plays important roles in negatively regulating the cellular inflammatory response. Recently, we found that as an RNase, MCPIP1 has broad-spectrum antiviral effects by targeting viral RNA. In this study, we demonstrated that MCPIP1 expression was induced by hepatitis C virus (HCV) infection in Huh7.5 hepatoma cells. MCPIP1 expression was higher in liver tissue from patients with chronic HCV infection compared with those without chronic HCV infection. Knockdown of MCPIP1 increased HCV replication and HCV-mediated expression of proinflammatory cytokines, such as TNF-α, IL-6, and MCP-1. However, overexpression of MCPIP1 significantly inhibited HCV replication and HCV-mediated expression of proinflammatory cytokines. Various mutants of functional domains of MCPIP1 showed disruption of the RNA binding and oligomerization abilities, as well as RNase activity, but not deubiquitinase activity, which impaired the inhibitory activity against HCV replication. On immunocytochemistry, MCPIP1 colocalized with HCV RNA. Use of a replication-defective HCV John Cunningham 1/AAG mutant and in vitro RNA cleavage assay demonstrated that MCPIP1 could directly degrade HCV RNA. MCPIP1 may suppress HCV replication and HCV-mediated proinflammatory responses with infection, which might contribute to the regulation of host defense against the infection and virus-induced inflammation.


Assuntos
Hepacivirus/fisiologia , Hepatite C Crônica/imunologia , Fatores de Transcrição/fisiologia , Replicação Viral , Linhagem Celular Tumoral , Quimiocina CCL2/biossíntese , Células HEK293 , Hepacivirus/genética , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Interleucina-6/biossíntese , Fígado/imunologia , Fígado/patologia , Fígado/virologia , Mutação , Estrutura Terciária de Proteína , Interferência de RNA , RNA Interferente Pequeno , RNA Viral/metabolismo , Proteínas de Ligação a RNA/genética , Ribonucleases , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/biossíntese , Proteases Específicas de Ubiquitina
15.
Biosci Trends ; 8(3): 138-43, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25030847

RESUMO

In this study, we examine the effect of chemokine (C-C motif) ligand 5 (CCL5)/Regulated on Activation Normal T cell Expressed and Secreted (RANTES), a pro-inflammatory cytokine on osteogenic differentiation of human mesenchymal stem cells (hMSCs). We found CCL5 expression was increased during osteogenic differentiation of hMSCs and CCL5 expression is dependent on the presence of dexamethasone. Knocking down endogenous CCL5 expression blocked osteogenesis, as revealed by decreasing alkaline phosphatase (ALP) activity and a reduction in the expression levels of ALP, bone sialoprotein (BSP), and osteopontin (OPN). Of note, the overexpression of CCL5 was sufficient to increase ALP expression and activity. Moreover, the down-regulation of chemokine (C-C motif) receptor 1 (CCR1), one of the CCL5 receptors, significantly decreased the osteogenesis of hMSCs. Interestingly, the down-regulation of CCR1, but not CCL5, was sufficient to affect the cell numbers during the process of osteogenesis. Our findings reveal that both CCL5 and CCR1 are required for osteogenesis of human MSCs, CCL5 is sufficient for the osteogenesis, and provide a novel link between dexamethasone and CCL5 in human osteogenesis.


Assuntos
Quimiocina CCL5/metabolismo , Dexametasona/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Quimiocina CCL5/genética , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Osteogênese/genética
16.
Kaohsiung J Med Sci ; 30(7): 323-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24924837

RESUMO

Resistance to chemotherapeutic drugs is one of the major challenges in the treatment of cancer. A better understanding of how resistance arises and what molecular alterations correlate with resistance is the key to developing novel effective therapeutic strategies. To investigate the underlying mechanisms of gemcitabine (Gem) resistance and provide possible therapeutic options, three Gem-resistant urothelial carcinoma sublines were established (NG0.6, NG0.8, and NG1.0). These cells were cross-resistant to arabinofuranosyl cytidine and cisplatin, but sensitive to 5-fluorouracil. The resistant cells expressed lower values of [hENT1 × dCK/RRM1 × RRM2] mRNA ratio. Two adenosine triphosphate-binding cassette proteins ABCD1 as well as multidrug resistance protein 1 were elevated. Moreover, cyclin D1, cyclin-dependent kinases 2 and 4 were upregulated, whereas extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase (MAPK) activity were repressed significantly. Administration of p38 MAPK inhibitor significantly reduced the Gem sensitivity in NTUB1 cells, whereas that of an extracellular signal-regulated kinase MAPK inhibitor did not. Furthermore, the Gem-resistant sublines also exhibited higher migration ability. Forced expression of p38 MAPK impaired the cell migration activity and augmented Gem sensitivity in NG1.0 cells. Taken together, these results demonstrate that complex mechanisms were merged in acquiring Gem resistance and provide information that can be important for developing therapeutic targets for treating Gem-resistant tumors.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/enzimologia , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Flavonoides/farmacologia , Humanos , Imidazóis/farmacologia , Piridinas/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/enzimologia
17.
Dev Comp Immunol ; 46(2): 117-28, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24731841

RESUMO

We cloned and sequenced 2C I-IFN, a two-cysteine containing type I interferon (I-IFN) gene, in orange-spotted grouper (Epinephelus coioides). The cDNA has 769 base pairs, the protein has 172 amino acids, and the predicted signal peptide has 18 amino acids with two cysteines. This gene is similar to I-FNs from sea bass and other teleosts. 2C I-IFN has 5 exons and 4 introns, also similar to other teleost I-IFNs. Immunohistochemical (IHC) analysis indicated that expression is predominantly membrane-localized in healthy grouper, but has a zonal distribution in nodavirus-infected grouper. Grouper infected with nodavirus had elevated levels of 2C I-IFN at 72 h and Mx at days 6-7. Recombinant 2C I-IFN activated grouper Mx, leading to upregulated antiviral activity. The grouper Mx promoter was highly induced after treatment with recombinant 2C I-IFN. The present results suggest that expression of grouper 2C I-IFN may participate in the immunologic barrier function against nodavirus.


Assuntos
Bass/genética , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Interferons/genética , Nodaviridae/imunologia , Infecções por Vírus de RNA/veterinária , Sequência de Aminoácidos , Animais , Sequência de Bases , Bass/imunologia , Bass/virologia , Linhagem Celular , Doenças dos Peixes/genética , Doenças dos Peixes/virologia , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica/imunologia , Imunidade Inata , Interferons/metabolismo , Dados de Sequência Molecular , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Especificidade de Órgãos , Filogenia , Regiões Promotoras Genéticas , Infecções por Vírus de RNA/genética , Infecções por Vírus de RNA/imunologia , Análise de Sequência de DNA
18.
AIDS ; 28(6): 841-9, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-24401640

RESUMO

OBJECTIVE: Despite evidence supporting antiretroviral therapy (ART) in recent HIV infection, little is known about factors that are associated with successful ART. We assessed demographic, virologic, and immunologic parameters to identify predictors of virologic response. DESIGN: A 24-week observational study of ART on persons enrolled within 6 months of their estimated date of infection (EDI) evaluated baseline demographics and the collection of blood and gut specimens. METHODS: Flow cytometry analyses of blood and gut lymphocytes allowed characterization of CD4 and CD8 T cells at study entry and end. Additional assessments included soluble CD14 (sCD14), lipopolysaccharide, CD4 T-cell counts, and HIV RNA levels. RESULTS: Twenty-nine participants initiated ART, and 17 achieved undetectable HIV RNA by study end. A longer time from EDI to ART, older age, higher sCD14, lower proportions of central memory CD4 T cells, and higher proportions of activated CD8 T cells were associated with detectable viremia. Multivariable logistic regression found only older age and elevated sCD14 were independently associated with persistent viremia. Additionally, we observed that ART in recent infection did not result in discernible recovery of CD4 T cells in the gut. CONCLUSION: In persons who started ART within 3-33 weeks from EDI, age and microbial translocation were associated with detectable HIV RNA. As observed in other cohorts, ART in recent infection did not improve proportions of total CD4 T cells in gut-associated lymphoid tissue (GALT). This lends support to further evaluate the use of more potent ART or regimens that protect the GALT in recent HIV infection.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Adulto , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Imunofenotipagem , Receptores de Lipopolissacarídeos/sangue , Lipopolissacarídeos/sangue , Masculino , Prognóstico , RNA Viral/sangue , Resultado do Tratamento , Carga Viral , Adulto Jovem
19.
Toxicol Sci ; 132(1): 43-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23174854

RESUMO

Chronic exposure to low-concentration arsenic promotes cell proliferation and carcinogenesis both in vitro and in vivo. Centrosome amplification, the major cause of chromosome instability, occurs frequently in cancers. Aurora-A is a mitotic kinase and causes centrosome amplification and chromosome instability when overexpressed. Our previous study revealed that low-concentration arsenic induces Aurora-A overexpression in immortalized bladder cells. In this study, we hypothesized that low-concentration arsenic induces aberrant mitosis in keratinocytes due to Aurora-A overexpression. The specimen of Bowen's disease (BD) and squamous cell carcinoma obtained from arseniasis-endemic areas in Taiwan showed Aurora-A overexpression. The mRNA/protein levels and kinase activity of Aurora-A were increased in immortalized keratinocyte HaCaT cells after arsenic treatment at low concentration (< 1µM). Aberrant spindles, multiple centrosomes, and multinucleated cells were detected under fluorescent microscopy in HaCaT cells after arsenic treatment. These findings were associated with increased expression of Aurora-A. We further revealed that Aurora-A was regulated by arsenic-induced transcriptional factor E2F1 as demonstrated by chromosome immunoprecipitation, promoter activity, and small interfering RNA assays. Finally, in arsenic-treated HaCaT cells and in BD, a significant increase of dysfunctional p53 was found, and this event correlated with the increase in expression of Aurora-A. Altogether, our data suggest that low concentration of arsenic induces activation of E2F1-Aurora-A axis and results in aberrant mitosis of keratinocytes. Overexpression of Aurora-A and dysfunctional p53 may act synergistically to trigger skin tumor formation. Our findings suggest that Aurora-A may be a potential target for the prevention and treatment of arsenic-related cancers.


Assuntos
Fator de Transcrição E2F1/fisiologia , Queratinócitos/efeitos dos fármacos , Mitose/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Transcrição Genética/fisiologia , Aurora Quinases , Western Blotting , Linhagem Celular , Imunoprecipitação da Cromatina , Relação Dose-Resposta a Droga , Imunofluorescência , Humanos , Imuno-Histoquímica , Queratinócitos/citologia , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/metabolismo , Proteína Supressora de Tumor p53/metabolismo
20.
Biochem Pharmacol ; 82(1): 35-42, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21477582

RESUMO

Gemcitabine (2'-deoxy-2', 2'-difluorocytidine; Gem) is a nucleoside anti-metabolite and is commonly used for treating various human cancers including human bladder carcinoma. Gemcitabine not only functions as a suicide nucleoside analog but also inhibits DNA polymerase activity and results in the termination of chain elongation. Using 2-dimensional gel electrophoresis analysis, a Gem-induced protein was identified as UBE2M (a.k.a. UBC12), a NEDD8 conjugation E2 enzyme which contributes to protein degradation. Gem induced UBE2M expression at both RNA and protein levels in several human cancer cell lines. The induction of UBE2M by Gem was accompanied by a reduction in p27(Kip1) protein levels, which could be restored by silencing UBE2M expression with siRNA or by treating cells with the proteasome inhibitor MG132, indicating that UBE2M mediates Gem-induced p27(Kip1) protein degradation. The induction of UBE2M and reduction of p27(Kip1) by Gem were prevented by the PI3K inhibitor LY294002. These results indicate that PI3K activity is necessary for Gem-induced UBE2M expression and that UBE2M facilitates degradation of p27(Kip1). Notably, silencing of UBE2M expression reduced Gem sensitivity in NTUB1 cells, suggesting that UBE2M mediates in part cell sensitivity to Gem, possibly by degradation of p27(Kip1). Analysis of Gem-resistant sub lines also showed that loss of UBE2M and increased p27(Kip1) expression were associated with the acquisition of drug resistance. In conclusion, our results demonstrate a role for UBE2M in mediating cytotoxicity of gemcitabine in human urothelial carcinoma cells while also suggesting a potential function of p27(Kip1) in drug resistance.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Desoxicitidina/análogos & derivados , Ubiquitinas/biossíntese , Western Blotting , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromonas/farmacologia , Inibidor de Quinase Dependente de Ciclina p27/genética , Desoxicitidina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Elafina/metabolismo , Formazans/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Morfolinas/farmacologia , RNA Interferente Pequeno/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Sais de Tetrazólio/metabolismo , Ubiquitinas/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
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