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1.
J Prosthet Dent ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39019724

RESUMO

STATEMENT OF PROBLEM: The complete arch implant-supported treatment concept with 2 angled implants has been widely used for the prosthetic rehabilitation of edentulous patients. While mechanical analysis plays a pivotal role in minimizing suboptimal outcomes or premature failure, it is notably time-consuming. Consequently, clinical treatment planning relies heavily on dentists' subjective judgment and an optimization process is needed. PURPOSE: The purpose of this study was to develop an optimization process for providing immediate recommendations to support decision-making in configuring complete arch implant-supported prostheses. MATERIAL AND METHODS: This research was carried out in 2 phases. The first consisted of collecting a dataset from a total of 2800 finite element simulations by randomly configuring 10 implant design variables with 4 types of mandibles. The dataset was used to train an artificial neural network to predict the biomechanical performance of a given complete arch implant-supported prosthesis design configuration. In the second phase, the artificial neural network was used as the objective function predictor in a particle swarm optimization process to enable immediate recommendations for the implant placement. The optimization process was evaluated for accuracy, computing performance, and adaptability for unseen mandibles. RESULTS: Within the specified design space, the optimization process was able to find an optimal design based on an imported mandible model in 30 seconds. The optimized designs were found to improve peri-implant stress by 11.08 ±6.43%. When verified through finite element analysis, the prediction error was found to be 10.4 ±8.1%. Furthermore, the prediction of the optimal design was highly accurate when tested on 2 unseen mandibles, yielding an error of less than 1.7%. CONCLUSIONS: The suggested approach can quickly provide an optimal implant configuration for each individual and effectively reduce the average peri-implant stress in the mandible.

2.
Blood ; 136(1): 11-23, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32276273

RESUMO

E2A, a basic helix-loop-helix transcription factor, plays a crucial role in determining tissue-specific cell fate, including differentiation of B-cell lineages. In 5% of childhood acute lymphoblastic leukemia (ALL), the t(1,19) chromosomal translocation specifically targets the E2A gene and produces an oncogenic E2A-PBX1 fusion protein. Although previous studies have shown the oncogenic functions of E2A-PBX1 in cell and animal models, the E2A-PBX1-enforced cistrome, the E2A-PBX1 interactome, and related mechanisms underlying leukemogenesis remain unclear. Here, by unbiased genomic profiling approaches, we identify the direct target sites of E2A-PBX1 in t(1,19)-positive pre-B ALL cells and show that, compared with normal E2A, E2A-PBX1 preferentially binds to a subset of gene loci cobound by RUNX1 and gene-activating machineries (p300, MED1, and H3K27 acetylation). Using biochemical analyses, we further document a direct interaction of E2A-PBX1, through a region spanning the PBX1 homeodomain, with RUNX1. Our results also show that E2A-PBX1 binding to gene enhancers is dependent on the RUNX1 interaction but not the DNA-binding activity harbored within the PBX1 homeodomain of E2A-PBX1. Transcriptome analyses and cell transformation assays further establish a significant RUNX1 requirement for E2A-PBX1-mediated target gene activation and leukemogenesis. Notably, the RUNX1 locus itself is also directly activated by E2A-PBX1, indicating a multilayered interplay between E2A-PBX1 and RUNX1. Collectively, our study provides the first unbiased profiling of the E2A-PBX1 cistrome in pre-B ALL cells and reveals a previously unappreciated pathway in which E2A-PBX1 acts in concert with RUNX1 to enforce transcriptome alterations for the development of pre-B ALL.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Regulação Leucêmica da Expressão Gênica/genética , Proteínas de Homeodomínio/fisiologia , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/fisiologia , Motivos de Aminoácidos , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Subunidade alfa 2 de Fator de Ligação ao Core/química , Subunidade alfa 2 de Fator de Ligação ao Core/genética , DNA/metabolismo , Elementos Facilitadores Genéticos , Código das Histonas , Proteínas de Homeodomínio/química , Humanos , Complexo Mediador/metabolismo , Proteínas de Fusão Oncogênica/química , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Domínios Proteicos , Mapeamento de Interação de Proteínas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Relação Estrutura-Atividade , Transcriptoma , Fatores de Transcrição de p300-CBP/metabolismo
3.
BMC Infect Dis ; 19(1): 536, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31215414

RESUMO

BACKGROUND: Enterobius vermicularis (pinworm) is one of the most common human parasitic helminths, and children are the most susceptible group. Some behavioral and environmental factors may facilitate pinworm infection. In the Republic of the Marshall Islands (RMI), the status of pinworm infections among children remains unknown. METHODS: In Majuro City, there are 14 kindergartens with a total of 635 preschool children (PSC) whose age range of 5~6 years. The present investigation attempted to determine the pinworm prevalence and associated risk factors as well as investigate whether eggs contaminated the clothes of PSC or the ground and tables in classrooms of 14 kindergartens. Informed consent form and a self-administered questionnaire were given to parents prior to pinworm screening. Perianal specimens were collected by an adhesive scotch tape method, and clothing of belly and hip sites and the ground and tables of the classrooms were inspected using a cellophane tape method to detect any eggs contamination. RESULTS: In total, 392 PSC (5.28 ± 0.56 yrs. old) participated in this project. The overall prevalence of pinworm infection was 22.4% (88/392). Boys (24.5%) had higher prevalence than girls (20.31%) (p = 0.32). PSC aged > 5 years (32.77%) showed a significantly higher prevalence than those aged ≤5 years (17.95%) (p = 0.01). A univariate analysis indicated that PSC who lived in urban areas (22.95%) had a higher prevalence than those who lived in rural areas (20.69%) (p = 0.69). The employment status of the parents showed no association with the pinworm infection rate (p > 0.05). A logistic regression analysis indicated that "having an older sister" produced a higher risk of acquiring pinworm infection for PSC compared to those who did not have an older sister (OR = 2.02; 95%CI = 1.05~3.88; p = 0.04). No significant association between various other risk factors and pinworm infection was found (p > 0.05). Also, no eggs contamination was found on the clothes of the belly and hip sites or on the ground and tables in the 14 kindergartens. CONCLUSIONS: Mass screening and treatment of infected PSC are important measures in pinworm control in the RMI.


Assuntos
Enterobíase/diagnóstico , Animais , Criança , Pré-Escolar , Enterobíase/epidemiologia , Enterobius/isolamento & purificação , Feminino , Humanos , Modelos Logísticos , Masculino , Micronésia/epidemiologia , Pais , Prevalência , Fatores de Risco , População Rural , Inquéritos e Questionários
4.
Cell Commun Signal ; 16(1): 19, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29703230

RESUMO

BACKGROUND: Golgin-97 is a tethering factor in the trans-Golgi network (TGN) and is crucial for vesicular trafficking and maintaining cell polarity. However, the significance of golgin-97 in human diseases such as cancer remains unclear. METHODS: We searched for a potential role of golgin-97 in cancers using Kaplan-Meier Plotter ( http://kmplot.com ) and Oncomine ( www.oncomine.org ) datasets. Specific functions of golgin-97 in migration and invasion were examined in golgin-97-knockdown and golgin-97-overexpressing cells. cDNA microarray, pathway analysis and qPCR were used to identify gene profiles regulated by golgin-97. The role of golgin-97 in NF-κB signaling pathway was examined by using subcellular fractionation, luciferase reporter assay, western blot analysis and immunofluorescence assay (IFA). RESULTS: We found that low expression of golgin-97 correlated with poor overall survival of cancer patients and was associated with invasiveness in breast cancer cells. Golgin-97 knockdown promoted cell migration and invasion, whereas re-expression of golgin-97 restored the above phenotypes in breast cancer cells. Microarray and pathway analyses revealed that golgin-97 knockdown induced the expression of several invasion-promoting genes that were transcriptionally regulated by NF-κB p65. Mechanistically, golgin-97 knockdown significantly reduced IκBα protein levels and activated NF-κB, whereas neither IκBα levels nor NF-κB activity was changed in TGN46- or GCC185-knockdown cells. Conversely, golgin-97 overexpression suppressed NF-κB activity and restored the levels of IκBα in golgin-97-knockdown cells. Interestingly, the results of Golgi-disturbing agent treatment revealed that the loss of Golgi integrity was not involved in the NF-κB activation induced by golgin-97 knockdown. Moreover, both TGN-bound and cytosolic golgin-97 inhibited NF-κB activation, indicating that golgin-97 functions as an NF-κB suppressor regardless of its subcellular localization. CONCLUSION: Our results collectively demonstrate a novel and suppressive role of golgin-97 in cancer invasiveness. We also provide a new avenue for exploring the relationship between the TGN, golgin-97 and NF-κB signaling in tumor progression.


Assuntos
Autoantígenos/metabolismo , Neoplasias da Mama/patologia , Proteínas da Matriz do Complexo de Golgi/metabolismo , NF-kappa B/metabolismo , Rede trans-Golgi/metabolismo , Autoantígenos/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Movimento Celular , Bases de Dados Factuais , Feminino , Proteínas da Matriz do Complexo de Golgi/antagonistas & inibidores , Proteínas da Matriz do Complexo de Golgi/genética , Humanos , Estimativa de Kaplan-Meier , Glicoproteínas de Membrana/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Fosforilação , Prognóstico , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo
5.
Environ Toxicol ; 33(12): 1321-1328, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30259639

RESUMO

4-methylimidazole (4-MI) is an imidazole-derived organic chemical compound that can be used as a raw material in the manufacture of diverse chemicals and has been identified as an ingredient of caramel color in soybean sauce, beers, and other soft drinks. The aim of the present study was to investigate the teratogenic effects of 4-MI during zebrafish embryogenesis. Zebrafish embryos were treated with different dosages of 4-MI (0-120 mM) for different exposure durations (12-60 hours). The percentages of embryos with malformed phenotypes increased as the exposure dosages and duration time of 4-MI increased. We also used immunofluorescence and transmission microscopy to evaluate the subtle changes in the myofibril alignment and ultrastructure of muscle organization. Our data showed that 4-MI treatment disturbs muscle fiber alignment. Electron microscopy data indicated that Z-lines were undetectable in the 4-MI-treated embryos. Although the thick and thin filaments were visible, they were all disorganized. In addition, zebrafish embryos treated by 4-MI exhibited aberrant expression of 2 muscle-specific genes, myod and myogenin. Taken together, we concluded that early exposure to 4-MI affects zebrafish myogenesis, especially in myofibril alignment.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Imidazóis/toxicidade , Desenvolvimento Muscular/efeitos dos fármacos , Miofibrilas/efeitos dos fármacos , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/efeitos dos fármacos , Miofibrilas/fisiologia , Proteínas de Peixe-Zebra/metabolismo
6.
Dev Med Child Neurol ; 59(1): 52-56, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27346658

RESUMO

AIM: The aim of the study was to investigate the risk of stroke in patients with cerebral palsy (CP), based on nationwide data in Taiwan. METHOD: This prospective cohort study was comprised of patients recorded on the Taiwan Longitudinal Health Insurance Database 2005 (LHID2005) who had a diagnosis of CP (n=1975) in records between 1 January 2004 and 31 December 2007. A comparison group (1:5) drawn from the same database was matched for age and sex (n=9875). Each patient was tracked by data until the development of stroke or the end of 2008. Cox proportional-hazards regression analysis was used to evaluate the hazard ratios after adjusting for potential confounding factors. RESULTS: Patients with CP were more likely to suffer stroke than the comparison population, after adjusting for potential confounding factors (adjusted hazard ratio: 2.17; 95% confidence interval [CI]: 1.74-2.69). The hazard ratio of stroke was 4.78 (95% CI: 3.18-7.17) and 1.57 (95% CI: 1.20-2.05) for patients with CP aged 50 years and under, and over 50 years respectively. INTERPRETATION: Cerebral palsy is a risk factor or marker for stroke that is independent of traditional stroke risk factors. Further research in this area is warranted.


Assuntos
Paralisia Cerebral/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Planejamento em Saúde Comunitária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde/estatística & dados numéricos , Estatísticas não Paramétricas , Taiwan/epidemiologia , Adulto Jovem
7.
J Appl Clin Med Phys ; 18(6): 114-122, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960724

RESUMO

In Gamma Knife forward treatment planning, normalization effect may be observed when multiple shots are used for treating large lesions. This effect can reduce the proportion of coverage of high-value isodose lines within targets. The aim of this study was to evaluate the performance of forward treatment planning techniques using the Leksell Gamma Knife for the normalization effect reduction. We adjusted the shot positions and weightings to optimize the dose distribution and reduce the overlap of high-value isodose lines from each shot, thereby mitigating the normalization effect during treatment planning. The new collimation system, Leksell Gamma Knife Perfexion, which contains eight movable sectors, provides an additional means to reduce the normalization effect by using composite shots. We propose different techniques in forward treatment planning that can reduce the normalization effect. Reducing the normalization effect increases the coverage proportion of higher isodose lines within targets, making the high-dose region within targets more uniform and increasing the mean dose to targets. Because of the increase in the mean dose to the target after reducing the normalization effect, we can set the prescribed marginal dose at a higher isodose level and reduce the maximum dose, thereby lowering the risk of complications.


Assuntos
Neoplasias Encefálicas/cirurgia , Neuroma Acústico/cirurgia , Planejamento de Assistência ao Paciente/normas , Radiocirurgia/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Algoritmos , Tronco Encefálico/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
8.
Arch Toxicol ; 90(1): 191-202, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25238743

RESUMO

Hypoxia is a common occurrence in brain tumors and traumatic brain injury. microRNA (miR)-1 participates in the regulation of brain development and neuronal function. Interestingly, miR-1 can mediate ischemia-induced injury to cardiomyocytes. This study was designed to evaluate the roles of miR-1 in hypoxia-induced insults to neurons and the possible mechanisms. Exposure of neuro-2a cells to oxygen/glucose deprivation (OGD) or cobalt chloride decreased cell viability and induced cell apoptosis in time-dependent manners. In parallel, OGD caused augmentation of cellular Bax and cytochrome c levels, a reduction in the mitochondrial membrane potential (MMP), activation of caspase-3, and fragmentation of DNA. miR-1 was induced in neuro-2a cells by OGD. Knocking down miR-1 expression using specific antisense inhibitors significantly alleviated OGD-induced neuronal death. Administration of OGD to neuro-2a cells induced heat-shock protein (HSP)-70 messenger (m)RNA and protein expressions. A bioinformatic search revealed that miR-1-specific binding elements exist in the 3'-untranslated region of HSP-70 mRNA. Overexpression of miR-1 simultaneously attenuated OGD-induced HSP-70 mRNA and protein expressions. In comparison, knocking down miR-1 expression synergistically enhanced OGD-induced HSP-70 mRNA. As to the mechanism, reducing miR-1 expression lowered OGD-induced alterations in the MMP, caspase-3 activation, DNA fragmentation, and cell apoptosis. Taken together, this study shows that miR-1 can target HSP-70 expression and consequently mediate hypoxia-induced apoptotic insults to neuro-2a cells via an intrinsic Bax-mitochondrion-caspase protease pathway.


Assuntos
Apoptose , MicroRNAs/metabolismo , Neurônios/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Cobalto/toxicidade , Fragmentação do DNA , Regulação da Expressão Gênica , Glucose/deficiência , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , MicroRNAs/genética , Neurônios/efeitos dos fármacos , Neurônios/patologia , Oxigênio/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção
9.
Eur J Clin Invest ; 45(12): 1297-305, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26479875

RESUMO

BACKGROUND: Exercise preconditioning (EP(+) ) has been widely accepted as a being of safe and effective preventive measure for stroke. The purpose of this study was to investigate whether EP(+) improves outcomes of ischaemic stroke by promoting neuronal and glial expression of heat shock protein (HSP) 20. MATERIALS AND METHODS: Adult male Sprague-Dawley rats (288 in number) were used to investigate the contribution of HSP20-containing neurons and HSP20-containing glial cells in the exercise-mediated neuroprotection in the stroke condition using middle cerebral artery occlusion. RESULTS: Exercise preconditioning, in addition to increasing the numbers of both the HSP20-containg neurons (88 ± 8 vs. 43 ± 4; n = 8 each group; P < 0·05) and the HSP20-containg astrocytes (102 ± 10 vs. 56 ± 5; n = 8; P < 0·05) significantly attenuated stroke-induced brain infarct (140 ± 9 vs. 341 ± 20 mm(3) ; n = 8 per group; P < 0·01), neuronal apoptosis (20 ± 5 vs. 87 ± 7; n = 8 per group; n = 8; P < 0·01), glial apoptosis (29 ± 5 vs. 101 ± 4; n = 8; P < 0·01), and neurological deficits (6·6 ± 0·3 vs. 11·7 ± 0·8; n = 8 per group; P < 0·01). Reducing the numbers of both HSP20-containing neurons and HSP20-contaiing glia by intracerebral injection of pSUPER small interfering RNAί expressing HSP20 significantly reversed the beneficial effects of EP(+) in attenuating stroke-induced cerebral infarct, neuronal and glial apoptosis, and neurological deficits. CONCLUSIONS: The numbers of both the HSP20-containing neurons and the HSP20-containing glia inversely correlated with the outcomes of ischaemic stroke. In addition, preischaemic treadmill exercise improves outcomes of ischaemic stroke by increasing the numbers of both the HSP20-containing neurons and the HSP20-containing glia.


Assuntos
Proteínas de Choque Térmico HSP20/fisiologia , Condicionamento Físico Animal/fisiologia , Acidente Vascular Cerebral/prevenção & controle , Animais , Apoptose/fisiologia , Astrócitos/metabolismo , Astrócitos/fisiologia , Infarto Encefálico/fisiopatologia , Lobo Frontal/metabolismo , Proteínas de Choque Térmico HSP20/metabolismo , Ligadura , Masculino , Artéria Cerebral Média , Neuroglia/metabolismo , Neuroglia/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia
10.
Int J Geriatr Psychiatry ; 30(7): 695-701, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25351738

RESUMO

BACKGROUND: To investigate the incidence and risk of hip fracture among dementia patients METHODS: This is a retrospective population-based 7-year cohort study using case-control matched analysis database from Taiwan's Longitudinal Health Insurance Database 2005. Patients were diagnosed with codes or International Classification of Diseases-9-CM codes of dementia, between 1 January 2004 and 31 December 2006. The prevalence and the adjusted odds ratio of hip fracture among dementia patients and the controls were estimated. RESULTS: We enrolled 3101 patients with dementia in the dementia cohort and 12,404 (1:4) patients in the control group. Of these, 202 patients experienced hip fractures. The incidence of hip fracture was 1178 per 100,000 person-years in the dementia cohort and 624 per 100,000 person-years in the comparison cohort. The hip fracture hazard ratio during the follow-up period was 1.89 (95% confidence interval [CI] 1.60-2.23, p < 0.001) for dementia patients. After adjusting for the covariates, the hazard ratio of hip fracture was 1.41 (95% CI, 1.19-1.69, p < 0.001) for dementia patients. CONCLUSION: People with dementia experience an increased incidence of hip fracture and are at a higher risk of sustaining a hip fracture in the future. Proper and effective hip fracture-prevention strategies are essential for dementia patients.


Assuntos
Demência/complicações , Fraturas do Quadril/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Fraturas do Quadril/etiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia
11.
Genet Med ; 16(10): 787-92, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24763291

RESUMO

PURPOSE: Schwannomatosis, a subtype of neurofibromatosis, is characterized by multiple benign, nonvestibular, nonintradermal schwannomas. Although the tumor suppressor SMARCB1 gene has been frequently identified as the underlying genetic cause of half of familial and ~10% of sporadic schwannomatosis, for most other cases, further causative genes remain to be discovered. Herein, we characterize the genome of a schwannomatosis family without constitutional inactivation of the SMARCB1 gene to explore novel genomic alterations predisposing individuals to the familial disease. METHODS: We performed whole-genome/exome sequencing on genomic DNA of both schwannomatosis-affected and normal members of the family. RESULTS: We identified a novel missense mutation (p.Asp208His; c.622G>C) in the coenzyme Q10 (CoQ10) biosynthesis monooxygenase 6 gene (COQ6) in schwannomatosis-affected members. The deleterious effects of the COQ6 mutations were validated by their lack of complementation in a coq6-deficient yeast mutant. Our study further indicated that the resultant haploinsufficiency of COQ6 might lead to CoQ10 deficiency and chronic overproduction of reactive oxygen species in Schwann cells. CONCLUSION: Although the exact oncogenetic mechanisms in this schwannomatosis family remain to be elucidated, our data strongly indicate a probable role of COQ6 mutation and CoQ10 deficiency in the development of familial schwannomatosis.Genet Med 16 10, 787-792.


Assuntos
Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa , Mutação de Sentido Incorreto , Neurilemoma/genética , Neurofibromatoses/genética , Neoplasias Cutâneas/genética , Ubiquinona/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Linhagem Celular , Células Cultivadas , Proteínas Cromossômicas não Histona/genética , Análise Mutacional de DNA/métodos , Proteínas de Ligação a DNA/genética , Saúde da Família , Técnicas de Silenciamento de Genes , Teste de Complementação Genética , Humanos , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Linhagem , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteína SMARCB1 , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/genética , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
12.
Cell Mol Neurobiol ; 34(6): 825-37, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24807460

RESUMO

Astragalosides (AST) are reported to be neuroprotective in focal cerebral ischemic models in vivo. In this study, the direct effect of AST against oxygen and glucose deprivation (OGD) including neuronal injury and the underlying mechanisms in vitro were investigated. 5 h OGD followed by 24 h of reperfusion [adding back oxygen and glucose (OGD-R)] was used to induce in vitro ischemia reperfusion injury in differentiated rat pheochromocytoma PC12 cells. AST (1, 100, and 200 µg/mL) were added to the culture after 5 h of the OGD ischemic insult and was present during the reoxygenation phases. A key finding was that OGD-R decreased cell viability, increased lactate dehydrogenase, increased reactive oxygen species, apoptosis, autophagy, functional impairment of mitochondria, and endoplasmic reticulum stress in PC12 cells, all of which AST treatment significantly reduced. In addition, AST attenuated OGD-R-induced cell loss through P38 MAPK activation a neuroprotective effect blunted by SB203580, a specific inhibitor of P38 MAPK. Our data suggest that both apoptosis and autophagy are important characteristics of OGD-R-induced PC12 death and that treating PC12 cells with AST blocked OGD-R-induced apoptosis and autophagy by suppressing intracellular oxidative stress, functional impairment of mitochondria, and endoplasmic reticulum stress. Our data provide identification of AST that can concomitantly inhibit multiple cells death pathways following OGD injuries in neural cells.


Assuntos
Glucose/metabolismo , Fármacos Neuroprotetores/farmacologia , Oxigênio/metabolismo , Saponinas/farmacologia , Acidente Vascular Cerebral/tratamento farmacológico , Triterpenos/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Mitocôndrias/metabolismo , Células PC12 , Ratos , Traumatismo por Reperfusão , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Arch Toxicol ; 87(3): 459-68, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23108914

RESUMO

MicroRNAs (miRNAs) can regulate cell survival and death by targeting apoptosis-related gene expression. miR-210 is one of the most hypoxia-sensitive miRNAs. In this study, we evaluated the roles of miR-210 in hypoxia-induced insults to neural cells. Treatment of neuro-2a cells with oxygen/glucose deprivation (OGD) induced cell apoptosis in a time-dependent manner. In parallel, OGD time-dependently increased cellular miR-210 levels. Knocking down miR-210 expression using specific antisenses significantly attenuated OGD-induced neural apoptosis. Concurrently, OGD increased hypoxia-inducible factor (HIF)-1α mRNA and protein syntheses. Pretreatment with YC-1, an inhibitor of HIF-1α, reduced OGD-caused cell death. Sequentially, OGD specifically decreased antiapoptotic Bcl-2 mRNA and protein levels in neuro-2a cells. A search by a bioinformatic approach revealed that miR-210-specific binding elements exist in the 3'-untranslated region of Bcl-2 mRNA. Application of miR-210 antisenses simultaneously alleviated OGD-involved inhibition of Bcl-2 mRNA expression. In comparison, overexpression of miR-210 synergistically diminished OGD-caused inhibition of Bcl-2 mRNA expression and consequently induced greater cellular insults. Taken together, this study shows that OGD can induce miR-210 expression through activating HIF-1α. And miR-210 can mediate hypoxia-induced neural apoptosis by targeting Bcl-2.


Assuntos
Apoptose , MicroRNAs/metabolismo , Neuroblastoma/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regiões 3' não Traduzidas , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Hipóxia Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glucose/deficiência , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Indazóis/farmacologia , Camundongos , Neuroblastoma/genética , Neuroblastoma/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , RNA Mensageiro/biossíntese , Fatores de Tempo , Transfecção
14.
Materials (Basel) ; 16(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36837132

RESUMO

Laser powder bed fusion (L-PBF) has attracted great interest in recent years due to its ability to produce intricate parts beyond the capabilities of traditional manufacturing processes. L-PBF processed biomedical implants are usually made of commercial pure titanium (CP-Ti) or its alloys. However, both alloys are naturally bio-inert, and thus reduce the formation of apatite as implants are put into the human body. Accordingly, in an attempt to improve the bioactivity of the materials used for making orthopedic implants, the present study decomposed fluorapatite material (FA, (Ca10(PO4)6F2)) into the form of nano-powder and mixed this powder with CP-Ti powder in two different ratios (99%Ti + 1%FA (Ti-1%FA) and 98%Ti + 2%FA (Ti-2%FA)) to form powder material for the L-PBF process. Experimental trials were conducted to establish the optimal processing conditions (i.e., laser power, scanning speed and hatching space) of the L-PBF process for the two powder mixtures and the original CP-Ti powder with no FA addition. The optimal parameters were then used to produce tensile test specimens in order to evaluate the mechanical properties of the different samples. The hardness of the various samples was also examined by micro-Vickers hardness tests. The tensile strength of the Ti-1%FA sample (850 MPa) was found to be far higher than that of the CP-Ti sample (513 MPa). Furthermore, the yield strength of the Ti-1%FA sample (785 MPa) was also much higher than that of the CP-Ti sample (472 MPa). However, the elongation of the Ti-1%FA sample (6.27 %) was significantly lower than that of the CP-Ti sample (16.17%). Finally, the hardness values of the Ti-1%FA and Ti-2%FA samples were around 63.8% and 109.4%, respectively, higher than that of the CP-Ti sample.

15.
Foods ; 12(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37509863

RESUMO

Research on the use of polysaccharides as hydrophobic bioactive carriers instead of proteins is still scarce. Sugar beet pectin (SBP) contains a small amount of protein and is a potential carrier for loading curcumin. In this work, SBP encapsulation, genipin crosslinking, and laccase-induced gelation were used to develop novel jelly food and improve the stability of curcumin without the incorporation of oil. By mixing the SBP solution (40 mg/mL) with curcumin powder (25 mg/mL SBP solution), an SBP-curcumin complex (SBP-Cur) was fabricated with a loading amount of 32 mg/g SBP, and the solubility of curcumin improved 116,000-fold. Fluorescence spectroscopy revealed that hydrophobic interactions drove the complexation of curcumin and SBP. Crosslinked by genipin (10 mM), SBP-Cur showed a dark blue color, and the gel strength of laccase-catalyzed gels was enhanced. Heating and UV radiation tests suggested that the genipin crosslinking and gelation strategies substantially improved the stability of curcumin. Because of the unique UV-blocking capacity of blue pigment, crosslinked samples retained 20% more curcumin than control samples. With the enhanced stability of curcumin, the crosslinked SBP-curcumin complexes could be a functional food ingredient used in functional drinks, baked food, and jelly food.

16.
Int J Biol Macromol ; 244: 125082, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37257538

RESUMO

Understanding molecular mechanisms during protein modification is critical for expanding the application of plant proteins. This study investigated the conformational change and molecular mechanism of pea protein isolate (PPI) under pulsed electric field (PEF)-assisted (-)-Epigallocatechin-Gallate (EGCG) modification. The flexibility of PPI was significantly enhanced after PEF treatment (10 kV/cm) with decrease (23.25 %) in α-helix and increase (117.25 %) in random coil. The binding constant and sites of PEF-treated PPI with EGCG were increased by 2.35 times and 10.00 % (308 K), respectively. Molecular docking verified that PEF-treated PPI had more binding sites with EGCG (from 4 to 10). The number of amino acid residues involved in hydrophobic interactions in PEF-treated PPI-EGCG increased from 5 to 13. PEF-treated PPI-EGCG showed a significantly increased antioxidant activity compared to non-PEF-treated group. This work revealed the molecular level of PEF-assisted EGCG modification of PPI, which will be significant for the application of PPI in food industry.


Assuntos
Proteínas de Ervilha , Simulação por Computador , Simulação de Acoplamento Molecular , Análise Espectral , Antioxidantes/farmacologia , Antioxidantes/química
17.
Front Med (Lausanne) ; 10: 1135570, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554508

RESUMO

Objectives: We assessed the efficacies of various corticosteroid treatments for preventing postexubation stridor and reintubation in mechanically ventilated adults with planned extubation. Methods: We searched the Pubmed, Embase, the Cochrane databases and ClinicalTrial.gov registration for articles published through September 29, 2022. Only randomized controlled trials (RCTs) that compared the clinical efficacies of systemic corticosteroids and other therapeutics for preventing postextubation stridor and reintubation were included. The primary outcome was postextubation stridor and the secondary outcome was reintubation. Results: The 11 assessed RCTs reported 4 nodes: methylprednisolone, dexamethasone, hydrocortisone, and placebo, which yielded 3 possible pairs for comparing the risks of post extubation stridor and 3 possible pairs for comparing the risks of reintubation. The risk of postextubation stridor was significantly lower in dexamethasone- and methylprednisolone-treated patients than in placebo-treated patients (dexamethasone: OR = 0.39; 95% CI = 0.22-0.70; methylprednisolone: OR = 0.22; 95% CI = 0.11-0.41). The risk of postextubation stridor was significantly lower in methylprednisolone-treated patients than in hydrocortisone-treated: OR = 0.24; 95% CI = 0.08-0.67) and dexamethasone-treated patients: OR = 0.55; 95% CI = 0.24-1.26). The risk of reintubation was significantly lower in dexamethasone- and methylprednisolone-treated patients than in placebo-treated patients: (dexamethasone: OR = 0.34; 95% CI = 0.13-0.85; methylprednisolone: OR = 0.42; 95% CI = 0.25-0.70). Cluster analysis showed that dexamethasone- and methylprednisolone-treated patients had the lowest risks of stridor and reintubation. Subgroup analyses of patients with positive cuff-leak tests showed similar results. Conclusions: Methylprednisolone and dexamethasone were the most effective agents against postextubation stridor and reintubation.

18.
Food Chem ; 377: 131945, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34999459

RESUMO

The present study investigated the effect of pulsed electric field (PEF) pretreatment on the interaction between bovine serum albumin (BSA) and curcumin. Fluorescence quenching results showed that proper PEF pretreatment significantly increased the binding affinity of curcumin and BSA, the binding constant increased by 6.77 times under the conditions of 15 kV/cm for 0.51 ms. However, at higher PEF strength (≥25 kV/cm) and longer processing time (≥0.68 ms), the binding affinity was weakened. PEF pretreatment made the protein structure more disordered and induced partial unfolding of BSA, exposing more hydrophobic regions, thereby increasing the binding affinity to curcumin. PEF-treated BSA (PBSA) possessed better encapsulation efficiency (95.19%) and loading capacity (5.25 mg/g) for curcumin, and the storage stability of curcumin were enhanced by the formation of a complex with PBSA. This study provides new insights into the design of BSA-based delivery systems for curcumin and other hydrophobic nutrients.


Assuntos
Curcumina , Soroalbumina Bovina , Eletricidade , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência
19.
Food Chem ; 372: 131280, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818732

RESUMO

In this study, the binding mechanism between bovine serum albumin (BSA) and three gingerols ([6]-, [8]- and [10]-gingerol) was evaluated to explore an effective strategy for improving solubility and stability of gingerols. The fluorescence analysis suggested gingerols could bind with BSA to form a stable BSA/gingerols complex and [10]-gingerol had the strongest binding affinity (Ka = 4.016 × 104 L/mol) at 298 K. Thermodynamic parameters and molecular modeling validated that hydrophobic interaction and hydrogen bonds were the main driving force for the interaction of BSA/gingerols. Gingerols bound to BSA at site I (subdomain IIA) resulted in a conformational change of BSA with a structure shrinkage, which was responsible for the decrease of surface hydrophobicity. The formation of BSA/gingerols complexes promoted the solubility of [6]-, [8]- and [10]-gingerol increasing by 1.50, 6.04 and 23.50 times, respectively. In addition, the stability and antioxidant capacity of gingerols was significantly improved after binding with BSA.


Assuntos
Soroalbumina Bovina , Sítios de Ligação , Catecóis , Dicroísmo Circular , Álcoois Graxos , Simulação de Acoplamento Molecular , Ligação Proteica , Soroalbumina Bovina/metabolismo , Solubilidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
20.
Sci Rep ; 12(1): 6452, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440793

RESUMO

Utilizing the optimal mass transportation (OMT) technique to convert an irregular 3D brain image into a cube, a required input format for a U-net algorithm, is a brand new idea for medical imaging research. We develop a cubic volume-measure-preserving OMT (V-OMT) model for the implementation of this conversion. The contrast-enhanced histogram equalization grayscale of fluid-attenuated inversion recovery (FLAIR) in a brain image creates the corresponding density function. We then propose an effective two-phase residual U-net algorithm combined with the V-OMT algorithm for training and validation. First, we use the residual U-net and V-OMT algorithms to precisely predict the whole tumor (WT) region. Second, we expand this predicted WT region with dilation and create a smooth function by convolving the step-like function associated with the WT region in the brain image with a [Formula: see text] blur tensor. Then, a new V-OMT algorithm with mesh refinement is constructed to allow the residual U-net algorithm to effectively train Net1-Net3 models. Finally, we propose ensemble voting postprocessing to validate the final labels of brain images. We randomly chose 1000 and 251 brain samples from the Brain Tumor Segmentation (BraTS) 2021 training dataset, which contains 1251 samples, for training and validation, respectively. The Dice scores of the WT, tumor core (TC) and enhanced tumor (ET) regions for validation computed by Net1-Net3 were 0.93705, 0.90617 and 0.87470, respectively. A significant improvement in brain tumor detection and segmentation with higher accuracy is achieved.


Assuntos
Neoplasias Encefálicas , Processamento de Imagem Assistida por Computador , Algoritmos , Encéfalo/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Progressão da Doença , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação
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