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1.
Mol Cell ; 82(5): 986-1002.e9, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35182480

RESUMO

Upon fertilization, embryos undergo chromatin reprogramming and genome activation; however, the mechanisms that regulate these processes are poorly understood. Here, we generated a triple mutant for Nanog, Pou5f3, and Sox19b (NPS) in zebrafish and found that NPS pioneer chromatin opening at >50% of active enhancers. NPS regulate acetylation across core histones at enhancers and promoters, and their function in gene activation can be bypassed by recruiting histone acetyltransferase to individual genes. NPS pioneer chromatin opening individually, redundantly, or additively depending on sequence context, and we show that high nucleosome occupancy facilitates NPS pioneering activity. Nucleosome position varies based on the input of different transcription factors (TFs), providing a flexible platform to modulate pioneering activity. Altogether, our results illuminate the sequence of events during genome activation and offer a conceptual framework to understand how pioneer factors interpret the genome and integrate different TF inputs across cell types and developmental transitions.


Assuntos
Cromatina , Nucleossomos , Animais , Cromatina/genética , Genoma/genética , Histonas/genética , Histonas/metabolismo , Nucleossomos/genética , Fatores de Transcrição SOX/genética , Fatores de Transcrição SOX/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
2.
Brain Behav Immun ; 115: 43-63, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37774892

RESUMO

Traumatic brain injury (TBI) and stroke share a common pathophysiology that worsens over time due to secondary tissue injury caused by sustained inflammatory response. However, studies on pharmacological interventions targeting the complex secondary injury cascade have failed to show efficacy. Here, we demonstrated that low-dose ionizing radiation (LDIR) reduced lesion size and reversed motor deficits after TBI and photothrombotic stroke. Magnetic resonance imaging demonstrated significant reduction of infarct volume in LDIR-treated mice after stroke. Systems-level transcriptomic analysis showed that genes upregulated in LDIR-treated stoke mice were enriched in pathways associated with inflammatory and immune response involving microglia. LDIR induced upregulation of anti-inflammatory- and phagocytosis-related genes, and downregulation of key pro-inflammatory cytokine production. These findings were validated by live-cell assays, in which microglia exhibited higher chemotactic and phagocytic capacities after LDIR. We observed substantial microglial clustering at the injury site, glial scar clearance and reversal of motor deficits after stroke. Cortical microglia/macrophages depletion completely abolished the beneficial effect of LDIR on motor function recovery in stroke mice. LDIR promoted axonal projections (brain rewiring) in motor cortex and recovery of brain activity detected by electroencephalography recordings months after stroke. LDIR treatment delayed by 8 h post-injury still maintained full therapeutic effects on motor recovery, indicating that LDIR is a promising therapeutic strategy for TBI and stroke.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Acidente Vascular Cerebral , Camundongos , Animais , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Acidente Vascular Cerebral/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Microglia/metabolismo , Radiação Ionizante , Camundongos Endogâmicos C57BL
3.
BMC Psychiatry ; 24(1): 328, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689236

RESUMO

BACKGROUND: Little evidence is available to verify the mediating effect of dispositional mindfulness on the association between gaming disorder and various impulsivity traits. The present study aimed to investigate the mediating effect of dispositional mindfulness on the association between the five UPPS-P impulsivity traits and the risk of gaming disorder among young adults. METHODS: It was an inter-regional cross-sectional study using online survey in Australia, Japan, The Philippines and China. Impulsivity measured by the UPPS-P Impulsive Behavior Scale-Short version; dispositional mindfulness measured by the Mindfulness Attention Awareness Scale; and the risk of gaming disorder measured by the Internet Gaming Disorder Scale were collected in the focal regions. Structural equation modeling was performed by SPSS AMOS version 26 to verify the study hypotheses. Bootstrapped 95% confidence interval was reported. Statistical significance was indicated by the p-value below 0.05. RESULTS: Among the 1,134 returned questionnaires, about 40% of them aged 18-20 years and 21-23 years, respectively. 53.8% were male. 40.7% had been playing digital and video games for over 10 years. The prevalence of gaming disorder was 4.32%. The model fitness indices reflected that the constructed model had an acceptable model fit (χ2(118) = 558.994, p < 0.001; χ2/df = 4.737; CFI = 0.924; TLI = 0.890; GFI = 0.948; RMSEA = 0.058; SRMR = 0.0487). Dispositional mindfulness fully mediated the effect of positive urgency and negative urgency on the risk of gaming disorder. The effect of lack of premeditation on the risk of gaming disorder was partially mediated by dispositional mindfulness. However, dispositional mindfulness did not mediate the effect of sensation seeking on the risk of gaming disorder. CONCLUSIONS: The varied associations between dispositional mindfulness and the five impulsivity traits hints that improving some impulsive traits may increase dispositional mindfulness and so lower the risk of gaming disorder. Despite further studies are needed to verify the present findings, it sheds light on the need to apply interventions on gamers based on their impulsivity profile. Interventions targeting at emotion regulation and self-control such as mindfulness-based interventions seem to be effective to help gamers with dominant features of urgency and lack of premeditation only. Other interventions shall be considered for gamers with high sensation seeking tendency to enhance the effectiveness of gaming disorder prevention.


Assuntos
Comportamento Impulsivo , Transtorno de Adição à Internet , Atenção Plena , Humanos , Masculino , Adulto Jovem , Feminino , Estudos Transversais , Adolescente , Transtorno de Adição à Internet/psicologia , Transtorno de Adição à Internet/epidemiologia , Adulto , Jogos de Vídeo/psicologia , Comportamento Aditivo/psicologia , Comportamento Aditivo/epidemiologia , Personalidade , Austrália/epidemiologia
4.
J Nurs Adm ; 54(5): 311-318, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648365

RESUMO

METHODS: This cross-sectional study sampled 833 nurses from 2 new hospitals in Guizhou Province, China. They completed a questionnaire on entrepreneurial leadership, nursing team creativity, innovation climate, creative self-efficacy, team psychological safety, and knowledge sharing. Data were analyzed using structural equation modeling. RESULTS: Entrepreneurial leadership positively influenced nursing team creativity. Innovation climate, creative self-efficacy, team psychological safety, and knowledge sharing mediated the relationship between entrepreneurial leadership and nursing team creativity in new hospitals. CONCLUSIONS: This study confirmed the significant role of innovation climate, creative self-efficacy, team psychological safety, and knowledge sharing in mediating the relationship between entrepreneurial leadership and nursing team creativity through empirical analysis.


Assuntos
Criatividade , Empreendedorismo , Liderança , Recursos Humanos de Enfermagem Hospitalar , Humanos , Estudos Transversais , Feminino , China , Recursos Humanos de Enfermagem Hospitalar/psicologia , Adulto , Masculino , Inquéritos e Questionários , Equipe de Enfermagem/organização & administração , Autoeficácia , Pessoa de Meia-Idade
5.
J Adv Nurs ; 80(3): 1222-1231, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37950400

RESUMO

AIM: To evaluate the clinical effectiveness and implementation strategies of telecare consultations in post-stroke nurse-led clinics. BACKGROUND: Telecare consultations could be an alternative to conventional in-person consultations and improve continuity of care for stroke survivors following their discharge from hospital. Previous studies utilizing telecare consultations only focused on testing their clinical effectiveness on stroke survivors; the appropriateness and feasibility of adopting this new delivery modality in a real-world setting were not examined. DESIGN: A Type II hybrid effectiveness-implementation design will be adopted. METHODS: Eligible stroke survivor participants will be randomly assigned to the intervention group (telecare consultation) or control group (usual in-person clinic consultation). Both groups will receive the same nursing intervention but delivered through different channels. The Reach, Effectiveness, Adoption, Implementation, Maintenance framework will be used to evaluate the clinical effectiveness and implementation outcomes. The primary outcome is the non-inferiority of the degree of disability between the two groups at 3 months into the intervention and at 3 months post-intervention. The paper complies with the SPIRIT guidelines for study protocols adapted for designing and reporting parallel group randomized trials. CONCLUSION: The findings of this study will provide key insights into the processes for implementing and adopting telecare consultations into long-term services for post-stroke patients. IMPACT: This study contributes to the translation of telecare consultations for stroke survivors into real-life settings. If effective, this program may provide guidance for expanding telecare consultations to other post-stroke nurse-led clinics or to patients with other chronic diseases. TRIAL REGISTRATION: This study has been registered at clinicaltrials.gov (identifier: NCT05183672). Registered on 10 January 2022.


Assuntos
Padrões de Prática em Enfermagem , Acidente Vascular Cerebral , Telemedicina , Humanos , Assistência ao Convalescente , Acidente Vascular Cerebral/terapia , Encaminhamento e Consulta , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Memory ; 31(9): 1244-1257, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37698244

RESUMO

Research shows that parents' self-worth may be contingent on their children's performance, with implications for their interactions with children. This study examined whether such child-based worth is manifested in parents' recognition memory. Parents of school-age children in China (N = 527) reported on their child-based worth and completed a recognition memory task involving evaluative trait adjectives encoded in three conditions: self-reference, child-reference, and semantic processing. The more parents had child-based worth, the more they exhibited a child-reference effect - superior recognition memory of evaluative trait adjectives encoded with reference to the child rather than semantically. Parents exhibited the classic self-reference effect in comparisons of recognition memory between the self-reference and semantic processing conditions, but this effect was not evidenced among parents high in child-based worth. Only parents low in child-based worth exhibited the self-reference effect in comparisons between the self-reference and child-reference conditions. Findings suggest that when parents hinge their self-worth on children's performance, evaluative information related to children may be an elaborate structure in memory.


Assuntos
Pais , Reconhecimento Psicológico , Humanos , China , Semântica
7.
Int J Mol Sci ; 24(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37762235

RESUMO

COVID-19 pandemic, caused by the SARS-CoV-2 virus, is still affecting the entire world via the rapid emergence of new contagious variants. Vaccination remains the most effective prevention strategy for viral infection, yet not all countries have sufficient access to vaccines due to limitations in manufacturing and transportation. Thus, there is an urgent need to develop an easy-to-use, safe, and low-cost vaccination approach. Genetically modified microorganisms, especially probiotics, are now commonly recognized as attractive vehicles for delivering bioactive molecules via oral and mucosal routes. In this study, Lactobacillus casei has been selected as the oral vaccine candidate based on its' natural immunoadjuvant properties and the ability to resist acidic gastric environment, to express antigens of SARS-CoV-2 Omicron variant B.1.1.529 with B-cell and T-cell epitopes. This newly developed vaccine, OMGVac, was shown to elicit a robust IgG systemic immune response against the spike protein of Omicron variant B.1.1.529 in Golden Syrian hamsters. No adverse effects were found throughout this study, and the overall safety was evaluated in terms of physiological and histopathological examinations of different organs harvested. In addition, this study illustrated the use of the recombinant probiotic as a live delivery vector in the initiation of systemic immunity, which shed light on the future development of next-generation vaccines to combat emerging infectious diseases.


Assuntos
COVID-19 , Vacinas , Animais , Cricetinae , Humanos , SARS-CoV-2/genética , Vacinas contra COVID-19 , Pandemias , COVID-19/prevenção & controle , Mesocricetus
8.
Phys Chem Chem Phys ; 24(3): 1580-1589, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34942640

RESUMO

The near-infrared light (NIR) absorption of nitrogen-doped graphene quantum dots (NGQDs) containing different N-doping sites is systematically investigated with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations with Perdew-Burke-Ernzerhof (PBE) functionals. The results show that the ultra-small HOMO-LUMO gaps (0.3-1.0 eV) of various N-doping structures (graphitic, amino, and pyridinic at center, and graphitic at edge) are attributed to the spin-polarization of the energy states, which effectively enhances the NIR absorption for NGQDs. Overall, the graphitic N-doping structure exhibits the best NIR absorption. Moreover, the electron attraction effect of the different N-sites is found to be crucial for the LUMO level, where stronger electron attraction lowers the LUMO energy. This work provides critical insight in further design of NGQDs for NIR absorption.

9.
Phys Chem Chem Phys ; 23(18): 10919-10925, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33912879

RESUMO

Photon-induced trap deactivation is commonly observed in organometal halide perovskites. Trap deactivation is characterized by an obvious photoluminescence (PL) enhancement. In this work, the properties of traps in CH3NH3PbI3 perovskite films were studied based on the PL enhancement excited by lasers of different wavelengths (633 nm and 405 nm). Two types of electron traps were identified; one can be deactivated by both 633 nm and 405 nm illuminations, whereas the other one can only be deactivated by 405 nm illumination. The energy levels of both types of traps were beneath the conduction band minimum. The expressions of the PL enhancement kinetics due to the trap deactivations by lasers of different wavelengths were derived. The ratio of the constants of the radiative recombination rate and the initial capture rates for both traps was determined from the PL enhancement. The trap deactivation was a photon-related process rather than a photocarrier-related process, and the deactivation time was inversely proportional to the photon flux density.

10.
PLoS Genet ; 14(7): e1007473, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29969449

RESUMO

Pre-mRNA splicing is a critical step of gene expression in eukaryotes. Transcriptome-wide splicing patterns are complex and primarily regulated by a diverse set of recognition elements and associated RNA-binding proteins. The retention and splicing (RES) complex is formed by three different proteins (Bud13p, Pml1p and Snu17p) and is involved in splicing in yeast. However, the importance of the RES complex for vertebrate splicing, the intronic features associated with its activity, and its role in development are unknown. In this study, we have generated loss-of-function mutants for the three components of the RES complex in zebrafish and showed that they are required during early development. The mutants showed a marked neural phenotype with increased cell death in the brain and a decrease in differentiated neurons. Transcriptomic analysis of bud13, snip1 (pml1) and rbmx2 (snu17) mutants revealed a global defect in intron splicing, with strong mis-splicing of a subset of introns. We found these RES-dependent introns were short, rich in GC and flanked by GC depleted exons, all of which are features associated with intron definition. Using these features, we developed and validated a predictive model that classifies RES dependent introns. Altogether, our study uncovers the essential role of the RES complex during vertebrate development and provides new insights into its function during splicing.


Assuntos
Proteínas de Transporte/metabolismo , Íntrons/genética , Splicing de RNA/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Encéfalo/embriologia , Proteínas de Transporte/genética , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Modelos Logísticos , Mutação com Perda de Função , Masculino , Modelos Genéticos , Proteínas de Peixe-Zebra/genética
11.
Br J Anaesth ; 123(2): 151-160, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31171343

RESUMO

BACKGROUND: Previous studies have shown that anaesthetic technique can affect outcomes of cancer surgery. We investigated the association between anaesthetic technique and patient outcomes after elective hepatectomy for hepatocellular carcinoma. METHODS: This was a retrospective single-centre cohort study of patients who received elective hepatectomy for hepatocellular carcinoma from January 2005 to December 2014. Patients were grouped according to propofol or desflurane anaesthesia. Kaplan-Meier analysis was performed and survival curves were constructed from the date of surgery to death. After propensity matching, univariable and multivariable Cox regression models were used to compare hazard ratios for death. Subgroup analyses were performed for tumour-node-metastasis staging and distant metastasis and local recurrence. RESULTS: A total of 492 patients (369 deaths, 75.0%) with desflurane anaesthesia and 452 (139 deaths, 30.8%) with propofol anaesthesia were eligible for analysis. After propensity matching, 335 patients remained in each group. In the matched analysis, propofol anaesthesia had a better survival with hazard ratio of 0.47 (95% confidence interval, 0.38-0.59; P<0.001). Subgroup analyses also showed significantly better survival in the absence of distant metastasis (hazard ratio, 0.47; 95% confidence interval, 0.37-0.60; P<0.001) or local recurrence (hazard ratio, 0.22; 95% confidence interval, 0.14-0.34; P<0.001) in the matched groups. CONCLUSIONS: Propofol anaesthesia was associated with better survival in hepatocellular carcinoma patients who underwent hepatectomy. Prospective studies are warranted to evaluate the effects of propofol anaesthesia on surgical outcomes in hepatocellular carcinoma patients.


Assuntos
Anestésicos Inalatórios , Carcinoma Hepatocelular , Isoflurano , Neoplasias Hepáticas , Propofol , Anestesia Intravenosa , Anestésicos Intravenosos , Estudos de Coortes , Desflurano , Hepatectomia , Humanos , Recidiva Local de Neoplasia , Estudos Prospectivos , Ablação por Radiofrequência , Estudos Retrospectivos
12.
Anal Chem ; 90(4): 2716-2724, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29353474

RESUMO

Immunoassay methods are important for monitoring ß-agonists illegally used for reducing animal fat deposition in livestock. However, there is no simultaneous screening surveillance immunoassay for detecting various ß-agonist chemicals that are possibly present in food. In this study, through the use of an R-(-)-salbutamol derivative as the immunizing hapten, an antibody recognizing 31 ß-agonists and analogues was generated for the first time. Three-dimensional quantitative structure-activity relationship (3D QSAR) revealed that strong steric and hydrophobic fields around the hapten spacer near C-2, as well as a chirality at C-1', dominantly modulated the class specificity of the raised antibody. However, a hapten spacer linked at C-2' or C-1 would lead to a narrow specificity, and the spacer charge at C-6 could affect the raised antibody specificity spectrum. A class specificity competitive indirect enzyme-linked immunosorbent assay (ciELISA) was established with an ideal recovery ranging from 81.8 to 118.3% based on the obtained antibody. With a good agreement to the HPLC/MS method, the proposed ciELISA was confirmed to be reliable for the rapid surveillance screening assay of ß-agonists in urine. This investigation will contribute to the rational design and control of the immunoassay specificity.


Assuntos
Agonistas Adrenérgicos beta/análise , Agonistas Adrenérgicos beta/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Haptenos/química , Haptenos/imunologia , Reações Antígeno-Anticorpo , Modelos Moleculares , Estrutura Molecular
13.
Anal Bioanal Chem ; 409(7): 1869-1875, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27988800

RESUMO

In recent years, digital polymerase chain reaction (dPCR) has gained recognition in biomedical research as it provides a platform for precise and accurate quantification of nucleic acids without the need for a standard curve. However, this technology has not yet been widely adopted as compared to real-time quantitative PCR due to its more cumbersome workflow arising from the need to sub-divide a PCR sample into a large number of smaller partitions prior to thermal cycling to achieve zero or at least one copy of the target RNA/DNA per partition. A recently launched platform, the Clarity™ system from JN Medsys, simplifies dPCR workflow through the use of a novel chip-in-a-tube technology for sample partitioning. In this study, the performance of Clarity™ was evaluated through quantification of the single-copy human RNase P gene. The system demonstrated high precision and accuracy and also excellent linearity across a range of over 4 orders of magnitude for the absolute quantification of the target gene. Moreover, consistent DNA copy measurements were also attained using a panel of different probe- and dye-based master mixes, demonstrating the system's compatibility with commercial master mixes. The Clarity™ was then compared to the QX100™ droplet dPCR system from Bio-Rad using a set of DNA reference materials, and the copy number concentrations derived from both systems were found to be closely associated. Collectively, the results showed that Clarity™ is a reliable, robust and flexible platform for next-generation genetic analysis.


Assuntos
Ácidos Nucleicos/análise , Reação em Cadeia da Polimerase/métodos , Humanos , Ribonuclease P/genética
14.
J Biochem Mol Toxicol ; 31(11)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28815806

RESUMO

Crotamine is defensin-like cationic peptide from rattlesnake venom that possesses anticancer, antimicrobial, and antifungal properties. Despite these promising biological activities, toxicity is a major concern associated with the development of venom-derived peptides as therapeutic agents. In the present study, we used zebrafish as a system model to evaluate the toxicity of rhodamine B-conjugated (RhoB) crotamine derivative. The lethal toxic concentration of RhoB-crotamine was as low as 4 µM, which effectively kill zebrafish larvae in less than 10 min. With non-lethal concentrations (<1 µM), crotamine caused malformation in zebrafish embryos, delayed or completely halted hatching, adversely affected embryonic developmental programming, decreased the cardiac functions, and attenuated the swimming distance of zebrafish. The RhoB-crotamine translocated across vitelline membrane and accumulated in zebrafish yolk sac. These results demonstrate the sensitive responsivity of zebrafish to trial crotamine analogues for the development of novel therapeutic peptides with improved safety, bioavailability, and efficacy profiles.


Assuntos
Venenos de Crotalídeos/toxicidade , Rodaminas/química , Testes de Toxicidade/métodos , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Venenos de Crotalídeos/química , Venenos de Crotalídeos/farmacocinética , Embrião não Mamífero/efeitos dos fármacos , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Coração/efeitos dos fármacos , Coração/embriologia , Larva/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Rodaminas/farmacocinética , Distribuição Tecidual
15.
Biochim Biophys Acta ; 1850(2): 373-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25450186

RESUMO

BACKGROUND: The role of Kdr (VEGFR-2/Flk-1) in vascular formation has been well described, but the role of Flt1 (VEGFR-1) is not well studied and is generally considered as a decoy receptor for trapping VEGF. METHODS: The effects of VEGFR1/2 kinase inhibitor (VRI) and calycosin on Flt1 tyrosine kinase (TK) activity were evaluated by molecular docking, enzymatic inhibition assay, protein co-immunoprecipitation and siRNA gene knock-down analysis in HUVECs. Toxicities of the chemicals were examined using HUVECs viability. Their effects on angiogenesis and vessel formation were furthered studied in HUVECs in vitro and Tg(fli-1:EGFP) zebrafish in vivo. The gene and protein expression of VEGF and VEGF receptors were investigated by quantitative RT-PCR and Western blot. RESULTS: VRI strongly inhibited physiological functions of both VEGF receptors and suppressed endothelial cell survival. This resulted in blood vessel loss in zebrafish embryos. Interestingly, calycosin co-treatment impeded VRI-induced blood vessel loss. Docking and kinase inhibition assay revealed that calycosin competed with VRI for the tyrosine kinase domain of Flt1 without affecting ATP binding. On the contrary, calycosin did not affect the interaction between VRI and Kdr-TK. Consistent with these results, calycosin counteracted the inhibition of Flt1-TK and PI3K phosphorylation induced by VRI in HUVECs. Further studies in vitro and in vivo showed that the minimizing effect of calycosin on VRI-mediated endothelial cytotoxicity was blocked by wortmannin (a PI3K inhibitor). The impeding effect of calycosin on VRI-induced blood vessel loss was absent in zebrafish embryos injected with Flt1 MO. CONCLUSIONS: Flt1-tyrosine kinase (TK) activity contributed significantly in endothelial cells survival and vascular development during embryo angiogenesis in zebrafish by engaging PI3K/Akt pathway. GENERAL SIGNIFICANCE: The roles of Flt1 activity in endothelial cell survival in physiological vascular formation may have been previously under-appreciated.


Assuntos
Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Endotélio Vascular/embriologia , Neovascularização Fisiológica/fisiologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/imunologia , Proteínas de Peixe-Zebra/imunologia , Peixe-Zebra/embriologia , Androstadienos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Embrião não Mamífero/citologia , Desenvolvimento Embrionário/efeitos dos fármacos , Endotélio Vascular/citologia , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Isoflavonas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Wortmanina , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética
16.
Pharm Biol ; 54(7): 1148-55, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26095111

RESUMO

CONTEXT: Natural products are good sources of natural dietary antioxidants that are believed to protect the body against hepatotoxic effect induced by oxidative stress. Hedyotis diffusa Willd (Rubiaceae) (HDW) is a traditional Chinese medicinal herb that has been shown to possess a variety of antioxidant properties. OBJECTIVE: The present study examines and explains the cell protective property of HDW water extract (WEHDW). MATERIALS AND METHODS: 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) assay was used to measure the free radical scavenging property of WEHDW (0.001-10 mg/mL). The protective effect of WEHDW (0.3-10 mg/mL 2 h pretreatment) against hydrogen peroxide (H2O2, 200 µM for 6 h) induced cytotoxicity in human hepatic cells, LO2, was evaluated using cell viability assay and nuclear staining. The molecular pathway of WEHDW's effect was investigated by using Western blot assay. RESULTS: WEHDW had a 50% scavenging concentration (SC50) at 0.153 mg/mL in the DPPH assay. Exposure of LO2 cells to H2O2 resulted in apoptosis which could be markedly attenuated by pre-treating WEHDW in a concentration-dependent manner (0.5, 1, 3, 5, or 10 mg/mL) (all with p < 0.001, versus control). Moreover, Hoechst (nuclear) staining showed that 1 mg/mL WEHDW could protect LO2 cells by attenuating apoptotic cell death mediated by H2O2. It was found that WEHDW reversed H2O2-induced activation of MEK/ERK pathway and H2O2-induced inhibition of P13-K/AKT/GSK3ß pathway in LO2 cells. DISCUSSION AND CONCLUSION: WEHDW may help to improve the antioxidant defense system, resulting in prevention of oxidative stress-related fatty liver diseases.


Assuntos
Antioxidantes/farmacologia , Hepatócitos/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Extratos Vegetais/farmacologia , Solventes/química , Água/química , Antioxidantes/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoproteção , Relação Dose-Resposta a Droga , Hedyotis/química , Hepatócitos/metabolismo , Hepatócitos/patologia , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Transdução de Sinais/efeitos dos fármacos
17.
Mol Pharm ; 12(10): 3507-17, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26291333

RESUMO

Flavonoid dimer FD18 is a new class of dimeric P-gp modulator that can reverse cancer drug resistance. FD18 is a potent (EC50 = 148 nM for paclitaxel), safe (selective index = 574), and selective P-glycoprotein (P-gp) modulator. FD18 can modulate multidrug resistance toward paclitaxel, vinblastine, vincristine, doxorubicin, daunorubicin, and mitoxantrone in human breast cancer LCC6MDR in vitro. FD18 (1 µM) can revert chemosensitivity of LCC6MDR back to parental LCC6 level. FD18 was 11- to 46-fold more potent than verapamil. FD18 (1 µM) can increase accumulation of doxorubicin by 2.7-fold, daunorubicin (2.1-fold), and rhodamine 123 (5.2-fold) in LCC6MDR. FD18 inhibited P-gp-mediated doxorubicin efflux and has no effect on influx. FD18 at 1 µM did not affect the protein expression level of P-gp. Pharmacokinetics studies indicated that intraperitoneal administration of 45 mg/kg FD18 was enough to maintain a plasma level above EC50 (148 nM) for more than 600 min. Toxicity studies with FD18 (90 mg/kg, i.p. for 12 times in 22 days) with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) revealed no obvious toxicity or death in mice. In vivo efficacy studies indicated that FD18 (45 mg/kg, i.p. for 12 times in 22 days) together with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) resulted in a 46% reduction in LCC6MDR xenograft volume (n = 11; 648 ± 84 mm(3)) compared to paclitaxel control (n = 8; 1201 ± 118 mm(3)). There were no animal deaths or significant drop in body weight and vital organ wet weight. FD18 can increase paclitaxel accumulation in LCC6MDR xenograft by 1.8- to 2.2-fold. The present study suggests that FD18 represents a new class of safe and potent P-gp modulator in vivo.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Flavonas/uso terapêutico , Flavonoides/uso terapêutico , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Feminino , Flavonas/efeitos adversos , Flavonas/farmacocinética , Flavonas/farmacologia , Flavonoides/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias
18.
J Stroke Cerebrovasc Dis ; 24(6): 1223-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25906936

RESUMO

BACKGROUND: Because of the limitation of on-site neurology workforce, telestroke was implemented to overcome this barrier. We explored the efficacy and safety of intravenous (IV) stroke thrombolysis service by telestroke when neurologist was not available on-site. METHODS: From January 2009 to December 2012, we compared patients treated with IV stroke thrombolysis by telestroke in the form of telephone consultation with teleradiology, to patients treated after in-person assessment by the same team of neurologists in a regional hospital. Door-to-needle time, symptomatic intracranial hemorrhage, and functional outcome at 3 months were prospectively collected and compared between the groups. RESULTS: In all, 152 patients were treated with IV thrombolysis; 102 patients were treated with neurologist on-site; whereas 50 patients were treated by internists with telestroke. Fifty-two percent of the telemedical group achieved excellent outcome compared to 43% of the neurologist on-site group (P = .30). Symptomatic intracranial hemorrhage rate (4.0% versus 4.9%, P = 1.0) and mortality (8.3% versus 11.9%, P = .49) were comparable. Using the multiple logistic regression analysis, age, baseline stroke severity, and extent of early ischemic change on brain computed tomography scan, are independent predictors for excellent outcome, whereas the presence of neurologist on-site is not correlated with the outcome. CONCLUSIONS: Patients treated without neurologist on-site achieved similar outcome. Telephone consultation and teleradiology-guided IV stroke thrombolysis, with the support of on-site internist appeared safe and efficacious.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Telemedicina/métodos , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Telefone , Telerradiologia/métodos , Resultado do Tratamento
19.
Toxicol Appl Pharmacol ; 280(3): 408-20, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25234792

RESUMO

In ischemic disorders such as chronic wounds and myocardial ischemia, there is inadequate tissue perfusion due to vascular insufficiency. Besides, it has been observed that prolonged use of anti-angiogenic agents in cancer therapy produces cardiovascular toxicity caused by impaired vessel integrity and regeneration. In the present study, we used VEGFR tyrosine kinase inhibitor II (VRI) to chemically induce vascular insufficiency in zebrafish in vivo and human umbilical vein endothelial cells (HUVEC) in vitro to further study the mechanisms of vascular morphogenesis in these pathological conditions. We also explored the possibility of treating vascular insufficiency by enhancing vascular regeneration and repair with pharmacological intervention. We observed that pretreatment of VRI induced blood vessel loss in developing zebrafish by inhibiting angiogenesis and increasing endothelial cell apoptosis, accompanied by down-regulation of kdr, kdrl and flt-1 genes expression. The VRI-induced blood vessel loss in zebrafish could be restored by post-treatment of calycosin, a cardiovascular protective isoflavone. Similarly, VRI induced cytotoxicity and apoptosis in HUVEC which could be rescued by calycosin post-treatment. Further investigation of the underlying mechanisms showed that the PI3K/AKT/Bad cell survival pathway was a main contributor of the vascular regenerative effect of calycosin. These findings indicated that the cardiovascular toxicity in anti-angiogenic therapy was mainly caused by insufficient endothelial cell survival, suggesting its essential role in vascular integrity, repair and regeneration. In addition, we showed that VRI-induced blood vessel loss in zebrafish represented a simple and effective in vivo model for studying vascular insufficiency and evaluating cancer drug vascular toxicities.


Assuntos
Apoptose/fisiologia , Isoflavonas/farmacologia , Neovascularização Fisiológica/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/fisiologia , Animais , Animais Geneticamente Modificados , Sobrevivência Celular/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia de Fluorescência , Simulação de Dinâmica Molecular , RNA/química , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Peixe-Zebra
20.
Pharmacol Res ; 90: 88-115, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25151891

RESUMO

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural polyphenolic compound that exists in Polygonum cuspidatum, grapes, peanuts and berries, as well as their manufactured products, especially red wine. Resveratrol is a pharmacologically active compound that interacts with multiple targets in a variety of cardiovascular disease models to exert protective effects or induce a reduction in cardiovascular risks parameters. This review attempts to primarily serve to summarize the current research findings regarding the putative cardioprotective effects of resveratrol and the molecular pathways underlying these effects. One intent is to hopefully provide a relatively comprehensive resource for clues that may prompt ideas for additional mechanistic studies which might further elucidate and strengthen the role of the stilbene family of compounds in cardiovascular disease and cardioprotection. Model systems that incorporate a significant functional association with tissues outside of the cardiovascular system proper, such as adipose (cell culture, obesity models) and pancreatic (diabetes) tissues, were reviewed, and the molecular pathways and/or targets related to these models and influenced by resveratrol are discussed. Because the body of work encompassing the stilbenes and other phytochemicals in the context of longevity and the ability to presumably mitigate a plethora of afflictions is replete with conflicting information and controversy, especially so with respect to the human response, we tried to remain as neutral as possible in compiling and presenting the more current data with minimal commentary, permitting the reader free reign to extract the knowledge most helpful to their own investigations.


Assuntos
Cardiotônicos/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Estilbenos/uso terapêutico , Animais , Cardiotônicos/farmacologia , Humanos , Resveratrol , Estilbenos/farmacologia
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