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1.
NPJ Vaccines ; 8(1): 175, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37945621

RESUMO

HIV affects more than 38 million people worldwide. Although HIV can be effectively treated by lifelong combination antiretroviral therapy, only a handful of patients have been cured. Therapeutic vaccines that induce robust de novo immune responses targeting HIV proteins and latent reservoirs will likely be integral for functional HIV cure. Our study shows that immunization of naïve rhesus macaques with arenavirus-derived vaccine vectors encoding simian immunodeficiency virus (SIVSME543 Gag, Env, and Pol) immunogens is safe, immunogenic, and efficacious. Immunization induced robust SIV-specific CD8+ and CD4+ T-cell responses with expanded cellular breadth, polyfunctionality, and Env-binding antibodies with antibody-dependent cellular cytotoxicity. Vaccinated animals had significant reductions in median SIV viral load (1.45-log10 copies/mL) after SIVMAC251 challenge compared with placebo. Peak viral control correlated with the breadth of Gag-specific T cells and tier 1 neutralizing antibodies. These results support clinical investigation of arenavirus-based vectors as a central component of therapeutic vaccination for HIV cure.

2.
Sci Rep ; 13(1): 3131, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823196

RESUMO

Remdesivir (GS-5734; VEKLURY) is a single diastereomer monophosphoramidate prodrug of an adenosine analog (GS-441524). Remdesivir is taken up by target cells and metabolized in multiple steps to form the active nucleoside triphosphate (GS-443902), which acts as a potent inhibitor of viral RNA-dependent RNA polymerases. Remdesivir and GS-441524 have antiviral activity against multiple RNA viruses. Here, we expand the evaluation of remdesivir's antiviral activity to members of the families Flaviviridae, Picornaviridae, Filoviridae, Orthomyxoviridae, and Hepadnaviridae. Using cell-based assays, we show that remdesivir can inhibit infection of flaviviruses (such as dengue 1-4, West Nile, yellow fever, Zika viruses), picornaviruses (such as enterovirus and rhinovirus), and filoviruses (such as various Ebola, Marburg, and Sudan virus isolates, including novel geographic isolates), but is ineffective or is significantly less effective against orthomyxoviruses (influenza A and B viruses), or hepadnaviruses B, D, and E. In addition, remdesivir shows no antagonistic effect when combined with favipiravir, another broadly acting antiviral nucleoside analog, and has minimal interaction with a panel of concomitant medications. Our data further support remdesivir as a broad-spectrum antiviral agent that has the potential to address multiple unmet medical needs, including those related to antiviral pandemic preparedness.


Assuntos
Filoviridae , Doença pelo Vírus Ebola , Infecção por Zika virus , Zika virus , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Monofosfato de Adenosina , Alanina , Doença pelo Vírus Ebola/tratamento farmacológico , Infecção por Zika virus/tratamento farmacológico
3.
Front Psychiatry ; 13: 897175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311518

RESUMO

Postpartum Depression (PPD) is a burden on women's mental health after delivery, predominantly occurring in the 1st year. PPD poses a threat to the mother's life and affects the quality of childcare. Early detection by family members of depressive symptoms is critical. This study aimed to examine the role of family members in reporting depressive symptoms of PPD among new mothers. A cross-sectional study was conducted, where 56 family members were asked to report depressive symptoms observed in new mothers. At the same time, the new mothers were also screened for PPD using the Edinburgh Postpartum Depression Scale (EPDS). Binary logistic regression was performed. Depressive symptoms of new mothers reported by family members, including emotional and behavioral disturbance, being under stress, high anxiety, isolation, changing lifestyle, and inability to take care of their children, were found as predictors of PPD.

4.
J Asian Econ ; 82: 101533, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35966036

RESUMO

Soon after the outbreak of the COVID-19 pandemic, many governments began extending financial and other forms of support to micro, small, and medium enterprises (MSMEs) and their workers because smaller firms are more vulnerable to negative shocks to their supply chain, labor supply, and final demand for goods and services than larger firms. Since MSMEs are diverse, however, the severity of the pandemic's impact on them varies considerably depending on their characteristics. Using online survey data of MSMEs from eight developing economies in South, Southeast, and Northeast Asia, this paper attempts to deepen our understanding of the impact of the pandemic on MSMEs, especially their employment, sales revenue, and cash flow. It also characterizes those firms that began participating in online commerce and tries to determine how their use of online commerce and their employment are related in this difficult time. This paper also examines the government support that MSMEs have received and the extent to which it has satisfied their support needs.

5.
Clin Pharmacol Ther ; 111(2): 416-424, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34623640

RESUMO

Tirabrutinib is an irreversible, small-molecule Bruton's tyrosine kinase (BTK) inhibitor, which was approved in Japan (VELEXBRU) to treat B-cell malignancies and is in clinical development for inflammatory diseases. As an application of model-informed drug development, a semimechanistic pharmacokinetic/pharmacodynamic (PK/PD) model for irreversible BTK inhibition of tirabrutinib was developed to support dose selection in clinical development, based on clinical PK and BTK occupancy data from two phase I studies with a wide range of PK exposures in healthy volunteers and in subjects with rheumatoid arthritis. The developed model adequately described and predicted the PK and PD data. Overall, the model-based simulation supported a total daily dose of at least 40 mg, either q.d. or b.i.d., with adequate BTK occupancy (> 90%) for further development in inflammatory diseases. Following the PK/PD modeling and simulation, the relationship between model-predicted BTK occupancy and preliminary clinical efficacy data was also explored and a positive trend was identified between the increasing time above adequate BTK occupancy and better efficacy in treatment for RA by linear regression.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Anti-Inflamatórios/administração & dosagem , Artrite Reumatoide/tratamento farmacológico , Imidazóis/administração & dosagem , Modelos Biológicos , Inibidores de Proteínas Quinases/administração & dosagem , Pirimidinas/administração & dosagem , Adolescente , Adulto , Tirosina Quinase da Agamaglobulinemia/metabolismo , Anti-Inflamatórios/farmacocinética , Artrite Reumatoide/enzimologia , Ensaios Clínicos Fase I como Assunto , Simulação por Computador , Cálculos da Dosagem de Medicamento , Feminino , Humanos , Imidazóis/farmacocinética , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/farmacocinética , Adulto Jovem
6.
Healthcare (Basel) ; 9(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34828516

RESUMO

BACKGROUND: We aimed to translate, cross-culturally adapt, and validate the General Medication Adherence Scale (GMAS) into Vietnamese. METHODS: We followed the guidelines of Beaton et al. during the translation and adaptation process. In Stage I, two translators translated the GMAS to Vietnamese. Stage II involved synthesizing the two translations. Stage III featured a back translation. Stage IV included an expert committee review and the creation of the pre-final version of the GMAS, and in stage V, pilot testing was conducted on 42 Vietnamese patients with type 2 diabetes. The psychometric validation process evaluated the reliability and validity of the questionnaire. The internal consistency and test-retest reliability were assessed by Cronbach's alpha and Spearman's correlation coefficients. The construct validity was determined by an association examination between the levels of adherence and patient characteristics. The content validity was based on the opinion and assessment score by the expert committee. The Vietnamese version of the GMAS was created, including 11 items divided into three domains. There was a good equivalence between the English and the Vietnamese versions of the GMAS in all four criteria. RESULTS: One hundred and seventy-seven patients were participating in the psychometric validation process. Cronbach's alpha was acceptable for all questionnaire items (0.817). Spearman's correlation coefficient of the test-retest reliability was acceptable for the GMAS (0.879). There are significant correlations between medication adherence levels and occupation, income, and the Beliefs about Medicines Questionnaire (BMQ) score regarding construct validity. CONCLUSIONS: The Vietnamese version of GMAS can be considered a reliable and valid tool for assessing medication adherence in Vietnamese patients.

7.
ACS Nano ; 14(4): 4276-4288, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167284

RESUMO

The area selective growth of polymers and their use as inhibiting layers for inorganic film depositions may provide a valuable self-aligned process for fabrication. Polynorbornene (PNB) thin films were grown from surface-bound initiators and show inhibitory properties against the atomic layer deposition (ALD) of ZnO and TiO2. Area selective control of the polymerization was achieved through the synthesis of initiators that incorporate surface-binding ligands, enabling their selective attachment to metal oxide features versus silicon dielectrics, which were then used to initiate surface polymerizations. The subsequent use of these films in an ALD process enabled the area selective deposition (ASD) of up to 39 nm of ZnO. In addition, polymer thickness was found to play a key role, where films that underwent longer polymerization times were more effective at inhibiting higher numbers of ALD cycles. Finally, while the ASD of a TiO2 film was not achieved despite blanket studies showing inhibition, the ALD deposition on polymer regions of a patterned film produced a different quality metal oxide and therefore altered its etch resistance. This property was exploited in the area selective etch of a metal feature. This demonstration of an area selective surface-grown polymer to enable ASD and selective etch has implications for the fabrication of both micro- and nanoscale features and surfaces.

8.
Sci Rep ; 9(1): 5013, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30899034

RESUMO

Identification of novel antibiotics remains a major challenge for drug discovery. The present study explores use of phenotypic readouts beyond classical antibacterial growth inhibition adopting a combined multiparametric high content screening and genomic approach. Deployment of the semi-automated bacterial phenotypic fingerprint (BPF) profiling platform in conjunction with a machine learning-powered dataset analysis, effectively allowed us to narrow down, compare and predict compound mode of action (MoA). The method identifies weak antibacterial hits allowing full exploitation of low potency hits frequently discovered by routine antibacterial screening. We demonstrate that BPF classification tool can be successfully used to guide chemical structure activity relationship optimization, enabling antibiotic development and that this approach can be fruitfully applied across species. The BPF classification tool could be potentially applied in primary screening, effectively enabling identification of novel antibacterial compound hits and differentiating their MoA, hence widening the known antibacterial chemical space of existing pharmaceutical compound libraries. More generally, beyond the specific objective of the present work, the proposed approach could be profitably applied to a broader range of diseases amenable to phenotypic drug discovery.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Descoberta de Drogas , Ensaios de Triagem em Larga Escala , Antibacterianos/química , Bactérias/patogenicidade , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Aprendizado de Máquina
9.
SLAS Discov ; 23(9): 919-929, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30011241

RESUMO

Bruton's tyrosine kinase (BTK) is a clinically validated target for B-cell leukemias and lymphomas with FDA-approved small-molecule inhibitors ibrutinib and acalabrutinib. Tirabrutinib (GS-4059/ONO-4059, Gilead Sciences, Inc., Foster City, CA) is a second-generation, potent, selective, irreversible BTK inhibitor in clinical development for lymphoid malignancies, including chronic lymphocytic leukemia (CLL) and diffuse large B-cell lymphoma (DLBCL). An accurate pharmacodynamic assay to assess tirabrutinib target coverage in phase 1/2 clinical studies will inform dose and schedule selection for advanced clinical evaluation. We developed a novel duplex homogeneous BTK occupancy assay based on time-resolved fluorescence resonance energy transfer (TR-FRET) to measure free and total BTK levels in a multiplexed format. The dual-wavelength emission property of terbium-conjugated anti-BTK antibody served as the energy donor for two fluorescent energy acceptors with distinct excitation and emission spectra. The assay was characterized and qualified using full-length purified recombinant human BTK protein and peripheral blood mononuclear cells derived from healthy volunteers and patients with CLL. We demonstrated assay utility using cells derived from lymph node and bone marrow samples from patients with CLL and DLBCL. Our TR-FRET-based BTK occupancy assay provides accurate, quantitative assessment of BTK occupancy in the clinical trial program for tirabrutinib and is in use in ongoing clinical studies.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Bioensaio , Imidazóis/farmacologia , Pirimidinas/farmacologia , Bioensaio/métodos , Bioensaio/normas , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Humanos , Imidazóis/química , Leucemia Linfocítica Crônica de Células B , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/química , Reprodutibilidade dos Testes
10.
J Oleo Sci ; 67(5): 617-626, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29628489

RESUMO

Candlenut oil (CNO) is a potentially new feedstock for biodiesel (BDF) production. In this paper, a two-step co-solvent method for BDF production from CNO was examined. Firstly, esterification of free fatty acids (FFAs) (7 wt%) present in CNO was carried out using a co-solvent of acetonitrile (30 wt%) and H2SO4 as a catalyst. The content of FFAs was reduced to 0.8 wt% in 1 h at 65°C. Subsequent transesterification of the crude oil produced was carried out using a co-solvent of acetone (20 wt%) and 1 wt% potassium hydroxide (KOH). Ester content of 99.3% was obtained at 40°C in 45 min. The water content in BDF was 0.023% upon purification using vacuum distillation at 5 kPa. The components of CNO BDF were characterized using a Fourier-transform infrared spectrometry and gas chromatography-flame ionization detector. The physicochemical properties of BDF satisfied the ASTM D6751-02 standard. The gaseous exhaust emissions from the diesel engine upon combustion of the BDF blends (B0-B100) with petrodiesel were examined. The emissions of carbon monoxide and hydrocarbons were clearly lower, but that of nitrogen oxides was higher in comparison to those from petro-diesel.


Assuntos
Aleurites , Biocombustíveis , Gases , Óleos de Plantas/química , Solventes/química , Acetona/química , Monóxido de Carbono , Catálise , Fenômenos Químicos , Esterificação , Ácidos Graxos não Esterificados/química , Ionização de Chama , Hidrocarbonetos , Hidróxidos/química , Óxidos de Nitrogênio , Compostos de Potássio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfúricos/química , Temperatura , Água
11.
Rev Sci Instrum ; 88(6): 065105, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28667961

RESUMO

This work focuses on design, construction, and optimization of configuration of a novel high voltage pulse power source for large-scale dielectric barrier discharge (DBD) generation. The pulses were generated by using the high-speed switching characteristic of an inexpensive device called silicon diodes for alternating current and the self-terminated characteristic of DBD. The operation started to be powered by a primary DC low voltage power supply flexibly equipped with a commercial DC power supply, or a battery, or DC output of an independent photovoltaic system without transformer employment. This flexible connection to different types of primary power supply could provide a promising solution for the application of DBD, especially in the area without power grid connection. The simple modular structure, non-control requirement, transformer elimination, and a minimum number of levels in voltage conversion could lead to a reduction in size, weight, simple maintenance, low cost of installation, and high scalability of a DBD generator. The performance of this pulse source has been validated by a load of resistor. A good agreement between theoretically estimated and experimentally measured responses has been achieved. The pulse source has also been successfully applied for an efficient DBD plasma generation.

12.
J Agric Food Chem ; 65(24): 4897-4904, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28541677

RESUMO

Alkaline treatment (Alk) combined with ultrasound-assisted extraction (UAE) (Alk+UAE) was examined as a means of extracting tocols and γ-oryzanol from rice bran into an organic phase while simultaneously recovering ferulic acid into an aqueous phase. The tocols and γ-oryzanol/ferulic acid yields were determined using high-performance liquid chromatography with fluorescence and UV detection. The effects of extraction conditions were evaluated by varying the Alk treatment temperature and extraction duration. The maximum yields of tocols and γ-oryzanol were obtained at 25 °C over a time span of 30 min. When the temperature was increased to 80 °C, the yield of ferulic acid increased dramatically, whereas the recovery of γ-oryzanol slightly decreased. Employing the Alk+UAE procedure, the recovered concentrations of tocols, γ-oryzanol, and ferulic acid were in the ranges of 146-518, 1591-3629, and 352-970 µg/g, respectively. These results are in good agreement with those reported for rice bran samples from Thailand.


Assuntos
Fracionamento Químico/métodos , Ácidos Cumáricos/isolamento & purificação , Oryza/química , Fenilpropionatos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ultrassom/métodos , Ácidos Cumáricos/química , Fenilpropionatos/química , Extratos Vegetais/química , Temperatura
13.
Lab Anim ; 51(1): 24-35, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26946120

RESUMO

Previous studies have established that 7,12-dimethylbenz(a)anthracene (DMBA) can initiate skin tumourigenesis in conventional furred mouse models by acting on hair follicle stem cells. However, further cancer progression depends on repeated applications of tumour promoter agents. This study evaluated the timeline involved in skin tumourigenesis and progression in immunocompetent hairless SKH1-hr mice with dysfunctional hair follicles using only DMBA with no additional tumour promoter agents. The results showed that topical application of 30 µg (117 nmol) of DMBA over the back and flank regions of the mouse once a week and 15 µg (58.5 nmol) twice a week produced skin tumours after 7-8 weeks. However, by week 14 a heavy benign tumour load required the mice to be euthanized. Lowering the DMBA dose to 15 µg (58.5 nmol) once a week produced tumours more slowly and allowed the mice to be studied for a longer period to week 23. This low-dose DMBA regimen yielded a high percentage of malignant tumours (58.8%) after 23 weekly applications. Additionally DMBA-treated skin showed an increase in mean epidermal thickness in comparison to untreated and acetone-treated skin. Despite the aberrant hair follicles in SKH1-hr mice, this chemically driven skin cancer model in hairless mice can serve as a suitable alternative to the ultraviolet-induced skin cancer models and can be reliably replicated as demonstrated by both the pilot and main experiments.


Assuntos
9,10-Dimetil-1,2-benzantraceno/farmacologia , Carcinogênese/induzido quimicamente , Progressão da Doença , Camundongos , Neoplasias Cutâneas/induzido quimicamente , 9,10-Dimetil-1,2-benzantraceno/administração & dosagem , Administração Tópica , Animais , Carcinógenos/administração & dosagem , Carcinógenos/farmacologia , Modelos Animais de Doenças , Feminino , Camundongos Pelados
14.
Cancer Metab ; 3: 11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26500770

RESUMO

BACKGROUND: Numerous studies have demonstrated that functional mitochondria are required for tumorigenesis, suggesting that mitochondrial oxidative phosphorylation (OXPHOS) might be a potential target for cancer therapy. In this study, we investigated the effects of BAY 87-2243, a small molecule that inhibits the first OXPHOS enzyme (complex I), in melanoma in vitro and in vivo. RESULTS: BAY 87-2243 decreased mitochondrial oxygen consumption and induced partial depolarization of the mitochondrial membrane potential. This was associated with increased reactive oxygen species (ROS) levels, lowering of total cellular ATP levels, activation of AMP-activated protein kinase (AMPK), and reduced cell viability. The latter was rescued by the antioxidant vitamin E and high extracellular glucose levels (25 mM), indicating the involvement of ROS-induced cell death and a dependence on glycolysis for cell survival upon BAY 87-2243 treatment. BAY 87-2243 significantly reduced tumor growth in various BRAF mutant melanoma mouse xenografts and patient-derived melanoma mouse models. Furthermore, we provide evidence that inhibition of mutated BRAF using the specific small molecule inhibitor vemurafenib increased the OXPHOS dependency of BRAF mutant melanoma cells. As a consequence, the combination of both inhibitors augmented the anti-tumor effect of BAY 87-2243 in a BRAF mutant melanoma mouse xenograft model. CONCLUSIONS: Taken together, our results suggest that complex I inhibition has potential clinical applications as a single agent in melanoma and also might be efficacious in combination with BRAF inhibitors in the treatment of patients with BRAF mutant melanoma.

15.
J Biophotonics ; 8(8): 668-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25319484

RESUMO

Early detection of cutaneous squamous cell carcinoma (cSCC) can enable timely therapeutic and preventive interventions for patients. In this study, in vivo nonlinear optical imaging (NLOI) based on two-photon excitation fluorescence (TPEF) and second harmonic generation (SHG), was used to non-invasively detect microscopic changes occurring in murine skin treated topically with 7,12-dimethylbenz(a)anthracene (DMBA). The optical microscopic findings and the measured TPEF-SHG index show that NLOI was able to clearly detect early cytostructural changes in DMBA treated skin that appeared clinically normal. This suggests that in vivo NLOI could be a non-invasive tool to monitor early signs of cSCC. In vivo axial NLOI scans of normal murine skin (upper left), murine skin with preclinical hyperplasia (upper right), early clinical murine skin lesion (lower left) and late or advanced murine skin lesion (lower right).


Assuntos
Carcinoma de Células Escamosas/patologia , Dinâmica não Linear , Imagem Óptica/métodos , Neoplasias Cutâneas/patologia , 9,10-Dimetil-1,2-benzantraceno/farmacologia , Animais , Carcinogênese/induzido quimicamente , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Pele/efeitos dos fármacos , Pele/patologia
16.
Nat Cell Biol ; 17(1): 57-67, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25487280

RESUMO

The rising incidence of obesity and related disorders such as diabetes and heart disease has focused considerable attention on the discovery of new therapeutics. One promising approach has been to increase the number or activity of brown-like adipocytes in white adipose depots, as this has been shown to prevent diet-induced obesity and reduce the incidence and severity of type 2 diabetes. Thus, the conversion of fat-storing cells into metabolically active thermogenic cells has become an appealing therapeutic strategy to combat obesity. Here, we report a screening platform for the identification of small molecules capable of promoting a white-to-brown metabolic conversion in human adipocytes. We identified two inhibitors of Janus kinase (JAK) activity with no precedent in adipose tissue biology that stably confer brown-like metabolic activity to white adipocytes. Importantly, these metabolically converted adipocytes exhibit elevated UCP1 expression and increased mitochondrial activity. We further found that repression of interferon signalling and activation of hedgehog signalling in JAK-inactivated adipocytes contributes to the metabolic conversion observed in these cells. Our findings highlight a previously unknown role for the JAK-STAT pathway in the control of adipocyte function and establish a platform to identify compounds for the treatment of obesity.


Assuntos
Adipócitos Marrons/citologia , Adipócitos Brancos/citologia , Janus Quinase 3/antagonistas & inibidores , Oxazinas/farmacologia , Piperidinas/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Animais , Proteína Morfogenética Óssea 7 , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Perfilação da Expressão Gênica , Proteínas Hedgehog/metabolismo , Humanos , Interferon gama/biossíntese , Interferon gama/farmacologia , Canais Iônicos/biossíntese , Janus Quinase 1/antagonistas & inibidores , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Proteínas Mitocondriais/biossíntese , Obesidade/prevenção & controle , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Fator de Transcrição STAT1/antagonistas & inibidores , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Necrose Tumoral alfa/farmacologia , Proteína Desacopladora 1 , Alcaloides de Veratrum/farmacologia
17.
Stem Cell Reports ; 3(4): 539-47, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25358782

RESUMO

Direct transdifferentiation of somatic cells is a promising approach to obtain patient-specific cells for numerous applications. However, conversion across germ-layer borders often requires ectopic gene expression with unpredictable side effects. Here, we present a gene-free approach that allows efficient conversion of human fibroblasts via a transient progenitor stage into Schwann cells, the major glial cell type of peripheral nerves. Using a multikinase inhibitor, we transdifferentiated fibroblasts into transient neural precursors that were subsequently further differentiated into Schwann cells. The resulting induced Schwann cells (iSCs) expressed numerous Schwann cell-specific proteins and displayed neurosupportive and myelination capacity in vitro. Thus, we established a strategy to obtain mature Schwann cells from human postnatal fibroblasts under chemically defined conditions without the introduction of ectopic genes.


Assuntos
Transdiferenciação Celular , Fibroblastos/citologia , Células de Schwann/citologia , Animais , Linhagem Celular , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Humanos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Ratos , Células de Schwann/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia
18.
Bioresour Technol ; 173: 309-316, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25310867

RESUMO

Biodiesel fuels (BDFs) was successfully produced from Vietnamese Jatropha curcas oil with high content of free fatty acids (FFAs) in two stages. In the first stage, the esterification process was carried out with the optimal conditions as follows; a methanol-to-FFAs molar ratio of 6:1, 1 wt% H2SO4, at a temperature of 65 °C, and using 30% (wt/wt) acetonitrile as co-solvent. This step reduced the concentration of FFAs in the reaction mixture from 15.93 to 2 wt% in 60 min. In the second stage, the transesterification process generated fatty acid methyl esters (FAMEs) with 99% efficiency was performed in 30 min with the optimal conditions as follows; a methanol-to-oil molar ratio of 6:1, 1 wt% KOH, at a temperature of 40 °C, and 20% (wt/wt) acetone as co-solvent. The produced biodiesel quality meets the standards JIS K2390 and EN 14214 regarding FAME yield, FFAs and water contents.


Assuntos
Biocombustíveis , Jatropha/química , Óleos de Plantas/química , Solventes/química , Esterificação , Ácidos Graxos não Esterificados/análise
19.
J Opt Soc Am A Opt Image Sci Vis ; 31(6): 1337-47, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24977374

RESUMO

Optical aberrations have detrimental effects in multiphoton microscopy. These effects can be curtailed by implementing model-based wavefront sensorless adaptive optics, which only requires the addition of a wavefront shaping device, such as a deformable mirror (DM) to an existing microscope. The aberration correction is achieved by maximizing a suitable image quality metric. We implement a model-based aberration correction algorithm in a second-harmonic microscope. The tip, tilt, and defocus aberrations are removed from the basis functions used for the control of the DM, as these aberrations induce distortions in the acquired images. We compute the parameters of a quadratic polynomial that is used to model the image quality metric directly from experimental input-output measurements. Finally, we apply the aberration correction by maximizing the image quality metric using the least-squares estimate of the unknown aberration.


Assuntos
Algoritmos , Artefatos , Aumento da Imagem/instrumentação , Lentes , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Refratometria/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
20.
Sci Signal ; 7(312): ra15, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24518294

RESUMO

Interactions with the extracellular matrix (ECM) through integrin adhesion receptors provide cancer cells with physical and chemical cues that act together with growth factors to support survival and proliferation. Antagonists that target integrins containing the ß1 subunit inhibit tumor growth and sensitize cells to irradiation or cytotoxic chemotherapy in preclinical breast cancer models and are under clinical investigation. We found that the loss of ß1 integrins attenuated breast tumor growth but markedly enhanced tumor cell dissemination to the lungs. When cultured in three-dimensional ECM scaffolds, antibodies that blocked ß1 integrin function or knockdown of ß1 switched the migratory behavior of human and mouse E-cadherin-positive triple-negative breast cancer (TNBC) cells from collective to single cell movement. This switch involved activation of the transforming growth factor-ß (TGFß) signaling network that led to a shift in the balance between miR-200 microRNAs and the transcription factor zinc finger E-box-binding homeobox 2 (ZEB2), resulting in suppressed transcription of the gene encoding E-cadherin. Reducing the abundance of a TGFß receptor, restoring the ZEB/miR-200 balance, or increasing the abundance of E-cadherin reestablished cohesion in ß1 integrin-deficient cells and reduced dissemination to the lungs without affecting growth of the primary tumor. These findings reveal that ß1 integrins control a signaling network that promotes an epithelial phenotype and suppresses dissemination and indicate that targeting ß1 integrins may have undesirable effects in TNBC.


Assuntos
Matriz Extracelular/metabolismo , Integrina beta1/metabolismo , Neoplasias Pulmonares/secundário , Metástase Neoplásica/fisiopatologia , Transdução de Sinais/fisiologia , Neoplasias de Mama Triplo Negativas/fisiopatologia , Animais , Western Blotting , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proteínas de Ligação a DNA/genética , Citometria de Fluxo , Inativação Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Imuno-Histoquímica , Integrina beta1/genética , Luciferases , Camundongos , Camundongos Knockout , MicroRNAs/metabolismo , Proteínas Repressoras/metabolismo , Imagem com Lapso de Tempo , Fator de Crescimento Transformador beta/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Peixe-Zebra , Homeobox 2 de Ligação a E-box com Dedos de Zinco
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