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1.
Development ; 144(2): 321-333, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27993984

RESUMO

The signal-induced proliferation-associated family of proteins comprises four members, SIPA1 and SIPA1L1-3. Mutations of the human SIPA1L3 gene result in congenital cataracts. In Xenopus, loss of Sipa1l3 function led to a severe eye phenotype that was distinguished by smaller eyes and lenses including lens fiber cell maturation defects. We found a direct interaction between Sipa1l3 and Epha4, building a functional platform for proper ocular development. Epha4 deficiency phenocopied loss of Sipa1l3 and rescue experiments demonstrated that Epha4 acts upstream of Sipa1l3 during eye development, with both Sipa1l3 and Epha4 required for early eye specification. The ocular phenotype, upon loss of either Epha4 or Sipa1l3, was partially mediated by rax We demonstrate that canonical Wnt signaling is inhibited downstream of Epha4 and Sipa1l3 during normal eye development. Depletion of either Sipa1l3 or Epha4 resulted in an upregulation of axin2 expression, a direct Wnt/ß-catenin target gene. In line with this, Sipa1l3 or Epha4 depletion could be rescued by blocking Wnt/ß-catenin or activating non-canonical Wnt signaling. We therefore conclude that this pathomechanism prevents proper eye development and maturation of lens fiber cells, resulting in congenital cataracts.


Assuntos
Olho/embriologia , Proteínas Ativadoras de GTPase/fisiologia , Cristalino/embriologia , Cristalino/crescimento & desenvolvimento , Receptor EphA4/fisiologia , Via de Sinalização Wnt/fisiologia , Animais , Animais Geneticamente Modificados , Catarata/genética , Diferenciação Celular/genética , Embrião não Mamífero , Olho/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Cristalino/metabolismo , Organogênese/genética , Ligação Proteica , Receptor EphA4/metabolismo , Xenopus/embriologia , Xenopus/genética
2.
J Neurochem ; 136(1): 28-35, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26364583

RESUMO

Rap GTPase-activating proteins (RapGAPs) are essential for synaptic function as they tightly regulate synaptic Rap signaling. Among the most abundant synaptic RapGAPs in brain are the Spine-associated RapGAPs (SPARs) Sipa1l1/SPAR and Sipa1l2/SPAR2, whereas nothing has been reported on Sipa1l3/SPAR3. In this study, we show that Sipa1l3/SPAR3 is conserved across species, has a distinct expression pattern in the developing rat brain and is localized at excitatory postsynapses. We further demonstrate that the Sipa1l3/SPAR3 C-terminus is required for postsynaptic targeting and represents an interaction module for Fezzins such as ProSAPiP1/Lzts3, a binding partner of the postsynaptic scaffold protein Shank3. Taken together, our data imply that Sipa1l3/SPAR3 is a hitherto unknown synaptic RapGAP, which is targeted to postsynaptic specializations and interacts with Fezzins. Spine-associated RapGAPs (SPARs) are essential modulators of synaptic signaling. Our study is the first to characterize the SPAR family member Sipa1l3/SPAR3 in neuronal tissue. We show that Sipa1l3/SPAR3 is conserved across species, has a distinct expression pattern in brain and is localized to excitatory postsynapses via its C-terminus, which represents an interaction module for other postsynaptic proteins including the Fezzin ProSAPiP1/Lzts3.


Assuntos
Proteínas de Transporte/biossíntese , Proteínas Ativadoras de GTPase/biossíntese , Proteínas de Membrana/biossíntese , Sinapses/metabolismo , Proteínas Supressoras de Tumor/biossíntese , Animais , Encéfalo/metabolismo , Células COS , Células Cultivadas , Chlorocebus aethiops , Cães , Feminino , Humanos , Masculino , Camundongos , Pan troglodytes , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie
3.
Front Public Health ; 11: 1160317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869200

RESUMO

Introduction: Driving fatigue has been shown to increase the risk of accidents and potentially fatal crashes. Fatigue is a serious risk that some drivers do not take seriously. Previous studies investigated the effects of driving fatigue in the Malaysian oil and gas transportation industry by employing survey questionnaires. However, they did not explain the behavior of fatigue. Besides, these results required validation by a more reliable method that can describe how fatigue occurs. Methods: Thus, in this study, we used the Psychomotor Vigilance Test (PVT-192) and a short survey to address driving fatigue behavior and identify the influences of driving fatigue on driving performance in real life (on the road) with actual oil and gas tanker drivers. The total participants in the experimental study were 58 drivers. Results: For the analysis, a Wilcoxon Signed Ranks Test, Z value and Spearman's rho were used to measure the significant difference between the pre and post-tests of PVT and the correlation between the fatigue variables and driving performance. Discussion: During the experiment's first and second days, this study's results indicated that driving fatigue gradually escalated. Likewise, there was a negative correlation based on the test of the relationship between the PVT data and the driving performance survey data. Additionally, the drivers suffer from accumulative fatigue, which requires more effort from the transportation company management to promote the drivers awareness of fatigue consequences.


Assuntos
Acidentes de Trânsito , Veículos Automotores , Humanos , Vigília , Meios de Transporte , Inquéritos e Questionários
4.
Front Public Health ; 10: 805733, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372179

RESUMO

Background: Social media activities affect every aspect of human life, be it personal, social or professional. Previous studies have confirmed the role of social media in affecting health in terms of releasing stress and providing social support. Increased occupational health disorders and increased time spent on social media activities motivate us to investigate this phenomenon in the context of occupational health. Therefore, the objective of this study is to measure the effects of social media activities related to personal and social life as well as work-life on health and wellbeing of office employees, on their job efforts and job rewards, and in moderating the effect of effort-reward imbalance on health and wellbeing. Methods: Initially, to develop constructs related to social media activities, web-based structured interviews were conducted with five office employees working in the oil and gas industry for the last 5 years. Then, using an online questionnaire survey, data was collected from 424 office employees working in the oil and gas industry in Malaysia. Using statistical software for social science (SPSS) and Smart PLS, exploratory factor analysis and confirmatory factor analysis were conducted to identify reliability and validity (discriminant validity, convergent validity and composite validity) of the constructs. Following this, path analysis was conducted and the moderating effects were identified. Results: Social media activities related to work-life decrease health and wellbeing by 11% and weaken the negative effect of effort-reward-imbalance on health and wellbeing by 17.6% at a 1% level of significance. The results of social media activities related to personal and social life strengthen the negative effect of effort-reward imbalance on health and wellbeing by 12% and negatively affects health and wellbeing and job rewards by 13, 55%, respectively. The direct effect of effort-reward imbalance and job efforts is significantly negative on health and wellbeing by 59 and 10%, respectively. Conclusion: It is concluded that social media activities of the office employees significantly moderate the effect of effort-reward imbalance on health and wellbeing and intervene in job rewards in the organizations. Hence, the effect of social media activities reduces the health and wellbeing of office employees.


Assuntos
Nível de Saúde , Saúde Mental , Indústria de Petróleo e Gás , Mídias Sociais , Humanos , Malásia , Reprodutibilidade dos Testes , Recompensa , Equilíbrio Trabalho-Vida
5.
Heliyon ; 8(11): e11289, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36353165

RESUMO

The adverse effects of work schedule on driving performance are relatively common. Therefore, it is necessary to fully understand an organisation's safety culture to improve driver performance in order to avoid road crashes. This study aims to investigate the moderating role of safety culture in the relationship between driver work schedules and driving performance. The study developed a conceptual framework based on the literature review of existing studies, which is supported by situation awareness theory that explains the model's relationships and supports the study's hypotheses. Three hundred four questionnaires were collected from oil and gas truck drivers then Structural equation modelling (SEM) was applied to test the study hypotheses. Derived from the findings, the outer loading for all items was above the threshold of 0.70 unless two items were deleted. The latent exogenous variables of safety culture and work schedule explained 59.1% of driving performance. Besides, work schedule and safety culture significantly impact driving performance. In addition, the results show that safety culture moderates the unfavourable work schedule impact on driving performance with an effect size of 23%. Therefore, this study showed strong evidence that safety culture acts as a critical moderator in reducing the negative impact of work schedule on driving performance in the energy transportation sector. Drivers with high safety culture can manage and reduce the effect of work schedule disorder on driving performance through their safety attitude and patterns compared to those drivers with low safety culture. Consequently, the improvement in driving performance will be noticed among drivers with a high awareness of safety culture.

6.
Int J Inj Contr Saf Promot ; 25(4): 401-407, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29616873

RESUMO

The study identifies the factors behind fatal and non-fatal road crashes in Lahore, Pakistan, by investigating 461 reported cases to Traffic Police Lahore that occurred during January-November 2014. Road crashes are categorized into fatal and non-fatal crashes and, because of the binary nature of the dependent variable, logistic regression is used to identify the factors behind these crashes. As a follow-up, discriminant analysis is employed to classify the factors related to fatal and non-fatal crashes. The logistic regression results reveal that females are at higher risk of fatalities than male drivers. Among vehicle types, rickshaws and cars are more involved in fatal accidents because both are growing at large on roads. Long trucks and trailers are also involved in fatal accidents, mainly because of their huge size and drivers' risky driving behaviours. It is also noted that risk of fatalities is higher in case where two vehicles bumped each other. Speeding and overloading are the common behaviours resulting in fatal crashes. Better urban transport systems and strict compliance with traffic rules and regulations may improve road safety in Pakistan.


Assuntos
Acidentes de Trânsito/mortalidade , Acidentes de Trânsito/estatística & dados numéricos , Veículos Automotores/estatística & dados numéricos , Condução de Veículo/legislação & jurisprudência , Feminino , Humanos , Modelos Logísticos , Masculino , Paquistão/epidemiologia , Pedestres/estatística & dados numéricos , Fatores de Risco , Assunção de Riscos , Fatores Sexuais , População Urbana
7.
J Zhejiang Univ Sci B ; 8(8): 599-603, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17657864

RESUMO

This study was undertaken to isolate and characterize the protease activity of human eye lens sample of mature and hyper mature cataract. Samples were collected just after surgery of the cataract lens and were stored at -20 degrees C. The total protein extract was isolated from 5 samples in each case (mature and hyper mature cataract) and clear supernatant obtained after centrifugation was used as an enzyme source. The optimum pH for the proteases of mature cataract was 7.5 while the proteases of hyper mature cataract were recorded for maximum activity at pH 5.5 and 7.5. The optimum temperature for both enzyme sources was 50 degrees C. Effect of different metal ions such as potassium, lead, silver, zinc and borate was studied. In each case protease activity was increased. Reducing agent e.g. beta mercaptoethanol also caused an increase in activity indicating the involvement of sulfhydryl groups. Protease activity was also located on agar plates.


Assuntos
Catarata/enzimologia , Catarata/patologia , Endopeptidases/metabolismo , Metais/farmacologia , Idoso , Aminoácidos/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Metais/química , Pessoa de Meia-Idade , Especificidade por Substrato
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