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1.
Curr Psychol ; 42(11): 8897-8918, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34400856

RESUMO

Motivated from the shortage of the existing research studies on impacts of dangerously contagious diseases on firms' financial performance, this study sheds light on the impacts of Coronavirus (Covid-19) outbreak on financial performance upon on the quarterly data of 126 Chinese listed firms across 16 industries. Overall, the Covid-19 outbreak reduced Chinese listed firms' financial performance proxied by the revenue growth rate, ROA, ROE, and asset turnover. This outbreak's negative effects on Chinese firms' profitability were much smaller than that on their revenue growth rates. While this outbreak's negative effects on financial performance of Chinese listed firms were bigger for those that were seriously affected by this pandemic like airlines, travel, and entertainment (ATE), this pandemic's effects were positive for the medicine industry. In the meanwhile, Chinese listed firms that located in high-risk regions suffered a bigger financial loss during the outbreak, and especially there was a strong Hubei effect. The corporate culture and CSR moderated the inverse relationship between this outbreak and Chinese firms' financial performance. Findings of this study contribute to enrich the existing literature on impacts of the Covid-19 outbreak on firms' financial performance worldwide and suggest helpful practical and theoretical implications.

2.
Front Public Health ; 10: 741490, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252078

RESUMO

BACKGROUND: The association between environmental and socioeconomic risk factors and the occurrence of hepatocellular carcinoma (HCC) are still inconclusive. A meta-analysis was conducted to address this issue. METHODS: We systematically searched the databases including PubMed, Web of Science, and Google Scholar and collected the related risk factors of HCC before March 6, 2020. Statistical analysis was performed on the odds ratio (OR) value and 95% CI of the correlation between environmental and socioeconomic factors and HCC. Begg's rank correlation test, Egger's linear regression test, and the funnel plot were employed for identification of the publication bias. RESULTS: Out of 42 studies, a total of 57,892 participants were included. Environmental and socioeconomic risk factors including ever educated (illiteracy); race (Black, Hispanic, and Asian); medium and low incomes; occupations (farmer and labor); passive smoking; place of residence (rural); blood aflatoxin B1 (AFB1) adduct level; exposure of pesticide, etc., were statistically increased with the occurrence of HCC (P < 0.05) and OR values and 95% CIs were 1.37 (1.00, 1.89), 2.42 (1.10-5.31), 1.90 (0.87-4.17), 5.36 (0.72-40.14), 1.48 (1.11, 1.96), 1.74 (1.00-3.03), 1.49 (1.06-2.08), 1.52 (1.07-2.18), 1.43 (0.27, 7.51), 1.46 (1.09, 1.96), 2.58 (1.67-3.97), and 1.52 (0.95-2.42), respectively. We found 6-9, 9-12, and ≥12 years of education that statistically reduced the risk of the occurrence of HCC (P < 0.05) and OR values and 95% CIs were 0.70 (0.58, 0.86), 0.52 (0.40, 0.68), and 0.37 (0.23, 0.59), respectively. No significant associations (P > 0.05) were observed between race (Hispanic and Asian), passive smoking, marital status, place of birth, place of residence, and HCC. In stratified analysis, exposure of pesticide was statistically significant (P < 0.05), while race of black was on the contrary. CONCLUSION: Environmental and socioeconomic risk factors have great impacts on the incidence rate of HCC. Improving national education and income levels can significantly reduce the risk of HCC. PROSPERO REGISTRATION: https://www.crd.york.ac.uk/prospero/, identifier: CRD42020151710.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Praguicidas , Poluição por Fumaça de Tabaco , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Fatores de Risco , Fatores Socioeconômicos
3.
Front Psychol ; 12: 708016, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707532

RESUMO

During the COVID-19 pandemic, enterprises were obliged to employ social media and digital tools to complete ordinary work. The pandemic has created a series of complexities and challenges, which have hampered harmonic contact between leaders and followers. The indirect relationship between unethical leadership and extra-role behavior (EXB) via psychological empowerment (PYE) is investigated in this study. We also look into the role of perceived organizational support (POS) as a moderator in the link between unethical leadership and PYE, as well as the indirect link between unethical leadership and EXB. Data were obtained from 258 supervisor-employee dyads from various small- and mid-sized information technology (IT) enterprises using time lag data. Unethical leadership has an impact on employee psychological empowerment as well as EXB. The findings of this study indicated that POS also mitigated the negative consequences of unethical leadership on employee psychological empowerment. Similarly, the role of psychological empowerment as a mediator in the link between unethical leadership and employee EXB is influenced by POS. This study will also benefit researchers and practitioners interested in human resource practices in the IT industry.

4.
J Environ Manage ; 299: 113558, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34425500

RESUMO

In order to contribute to the existing limited energy-environment literature, the present study analyze the carbon neutrality targets of the 16 major exporting economies while considering the role of economic complexity and renewable energy electricity consumption empirically by investigating the most recent dataset covering the period from 1990 to 2019 by employing advanced econometric techniques. This study uses the economic complexity index, connecting the country's productive structure with the amount of knowledge that the products represent. Employing various cointegration and regression techniques such as augmented mean group (AMG) and dynamic ordinary least square (DOLS) confirms the long-run cointegration among the variables such as economic growth, economic complexity, renewable energy consumption, and CO2 emission. Also, this study provides evidence that confirms the validity of the environmental Kuznets curve hypothesis in the leading exporting economies. Regarding the carbon neutrality target, we found that both economic complexity and renewable electricity, if increase by one percent each, significantly reduce CO2 emissions by 0.1491 (AMG) and 0.130% (DOLS) and 0.160 (AMG) and 0.203% (DOLS), respectively, that help attain the carbon neutrality target.


Assuntos
Dióxido de Carbono , Carbono , Desenvolvimento Econômico , Eletricidade , Energia Renovável
5.
Br J Pharmacol ; 176(17): 3180-3192, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31140595

RESUMO

BACKGROUND AND PURPOSE: Hydrogen sulfide donors can block the cardiovascular injury of hyperhomocysteinemia. H2 S also lowers serum homocysteine in rats with mild hyperhomocysteinemia, but the pharmacological mechanism is unknown. The present study investigated the mechanism(s) involved. EXPERIMENTAL APPROACH: ApoE-knockout mice were fed a Paigen diet and L-methionine in drinking water for 16 weeks to create a mouse model of atherosclerosis with hyperhomocysteinemia. H2 S donors (NaHS and GYY4137) were administered by intraperitoneal injection. We also assayed the H2 S produced (by methylene blue assay and mito-HS [H2 S fluorescence probe]), cystathionine γ lyase (CSE) mRNA and protein expression, and CSE sulfhydration and nitrosylation and its activity. KEY RESULTS: H2 S donor treatment significantly lowered atherosclerotic plaque area, macrophage infiltration, and serum homocysteine level in the mouse model of atherosclerosis with co-existing hyperhomocysteinemia. mRNA and protein levels of CSE, a key enzyme catalyzing homocysteine trans-sulfuration, were down-regulated with hyperhomocysteinemia, and CSE catalytic activity was inhibited. All these effects were reversed with H2 S donor treatment. Hyperhomocysteinemia induced CSE nitrosylation, whereas H2 S sulfhydrated CSE at the same cysteine residues. Nitrosylated CSE decreased and sulfhydrated CSE increased its catalytic and binding activities towards L-homocysteine. Mutation of C252, C255, C307, and C310 residues in CSE abolished CSE nitrosylation or sulfhydration and prevented its binding to L-homocysteine. CONCLUSIONS AND IMPLICATIONS: Sulfhydration or nitrosylation of CSE represents a yin/yang regulation of catalysis or binding to L-homocysteine. H2 S donor treatment enhanced CSE sulfhydration, thus lowering serum L-homocysteine, which contributed in part to the anti-atherosclerosis effects in ApoE-knockout mice with hyperhomocysteinemia.


Assuntos
Aterosclerose/tratamento farmacológico , Cistationina gama-Liase/metabolismo , Sulfeto de Hidrogênio/farmacologia , Hiper-Homocisteinemia/tratamento farmacológico , Animais , Aterosclerose/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células HEK293 , Células Hep G2 , Humanos , Sulfeto de Hidrogênio/análise , Sulfeto de Hidrogênio/metabolismo , Hiper-Homocisteinemia/metabolismo , Masculino , Camundongos , Camundongos Knockout para ApoE , Relação Estrutura-Atividade
6.
Front Chem ; 7: 232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31065549

RESUMO

Foodborne pathogens, especially bacteria, are explicitly threatening public health worldwide. Biosensors represent advances in rapid diagnosis with high sensitivity and selectivity. However, multiplexed analysis and minimal pretreatment are still challenging. We fabricate a gold nanoparticle (Au NP)-amplified microcantilever array biosensor that is capable of determining ultralow concentrations of foodborne bacteria including Escherichia coli O157:H7, Vibrio parahaemolyticus, Salmonella, Staphylococcus aureus, Listeria monocytogenes, Shigella, etc. The method is much faster than using conventional tools without germiculturing and PCR amplification. The six pairs of ssDNA probes (ssDNA1 + ssDNA2 partially complementary to the target gene) that originated from the sequence analysis of the specific gene of the bacteria were developed and validated. The ssDNA1 probes were modified with -S-(CH2)6 at the 5'-end and ready to immobilize on the self-assembled monolayers (SAMs) of the sensing cantilevers in the array and couple with Au NPs, while 6-mercapto-1-hexanol SAM modification was carried out on the reference cantilevers to eliminate the interferences by detecting the deflection from the environment induced by non-specific interactions. For multianalyte sensing, the target gene sequence was captured by the ssDNA2-Au NPs in the solution, and then the Au NPs-ssDNA2-target complex was hybridized with ssNDA1 fixed on the beam of the cantilever sensor, which results in a secondary cascade amplification effect. Integrated with the enrichment of the Au NP platform and the microcantilever array sensor detection, multiple bacteria could be rapidly and accurately determined as low as 1-9 cells/mL, and the working ranges were three to four orders of magnitude. There was virtually no cross-reaction among the various probes with different species. As described herein, it holds great potential for rapid, multiplexed, and ultrasensitive detection in food, environment, clinical, and communal samples.

7.
Antioxid Redox Signal ; 30(2): 184-197, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29343087

RESUMO

Aims: Hydrogen sulfide (H2S) has a protective role in the pathogenesis of atherosclerosis by multiple pathways. Sirtuin-1 (SIRT1) is a histone deacetylase, as an essential mediated longevity gene, and has an anti-atherogenic effect by regulating the acetylation of some functional proteins. Whether SIRT1 is involved in protecting H2S in atherosclerosis and its mechanism remains unclear. Results: In ApoE-knockout atherosclerosis mice, treatment with an H2S donor (NaHS or GYY4137) reduced atherosclerotic plaque area, macrophage infiltration, aortic inflammation, and plasma lipid level. H2S treatment increased aorta and liver SIRT1 mRNA expression. Overexpression or slicing cystathionine gamma lyase (CSE) also changed intracellular SIRT1 expression. CSE/H2S treatment increased SIRT1 deacetylation in endothelium and hepatocytes and macrophages, then induced deacetylation of its target proteins (P53, P65, and sterol response element binding protein), thereby reducing endothelial and macrophage inflammation and inhibiting macrophage cholesterol uptake and cholesterol de novo synthesis of liver. Also, CSE/H2S induced SIRT1 sulfhydration at its two zinc finger domains, increased its zinc ion binding activity to stabilize the alpha-helix structure, lowered its ubiquitination, and reduced its degradation. Innovation: H2S is a novel SIRT1 activator by direct sulfhydration. Because SIRT1 has a role in longevity, H2S may be a protector for aging-related diseases. Conclusion: Endogenous CSE/H2S directly sulfhydrated SIRT1, enhanced SIRT1 binding to zinc ion, then promoted its deacetylation activity, and increased SIRT1 stability, thus reducing atherosclerotic plaque formation.


Assuntos
Aterosclerose/etiologia , Aterosclerose/metabolismo , Epigênese Genética , Sulfeto de Hidrogênio/farmacologia , Sirtuína 1/metabolismo , Acetilação , Animais , Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Biomarcadores , Linhagem Celular , Colesterol/metabolismo , Modelos Animais de Doenças , Endotélio/metabolismo , Células Espumosas/metabolismo , Células Espumosas/patologia , Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Processamento de Proteína Pós-Traducional , Sirtuína 1/genética , Ubiquitinação
8.
Biochim Biophys Acta Mol Basis Dis ; 1864(10): 3281-3291, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30010047

RESUMO

Hydrogen sulfide (H2S) is an essential neuromodulator, generates by cystathionine ß synthase (CBS) or 3-mecaptopyruvate sulfurtransferase (3MST) in the brain. H2S can mediate paraventricular nucleus (PVN) neuron activity, and regulate neuroendocrine hormones secretion. On the other hand, CBS deficiency caused metabolic disorder and body weight reduction. However, whether CBS/H2S of PVN regulates neuroendocrine hormones to mediate energy metabolism is unknown. Here, we first identified the CBS co-localization with thyrotropin-releasing hormone (TRH) and corticotropin releasing hormone (CRH) positive neurons. In HFD induced obese rats, CBS protein of hypothalamus decreased. By contrast, overexpression CBS in PVN via lentivirus, lowered food uptake, body weight and fat mass, and reduced blood glucose, lipid disorders and insulin resistance. Intriguingly, CBS overexpression increased the pre-TRH expression, slightly elevated plasma thyroxine and thyrotropin level, but decreased the plasma ACTH and corticosterone level. Then, we found that mTOR activation contributed to pre-TRH up-regulation by CBS/H2S system. In db/db obese mice, hypothalamus CBS/H2S system also down-regulated association with reduction pre-TRH expression; in contrast, CBS overexpression in PVN slightly elevated plasma leptin. Next, leptin stimulated FOXO3a nuclear translocation, increased FOXO3a binding activity to two binding sites of CBS promoter, and then enhanced CBS protein expression. In conclusion, leptin activates neuron CBS-H2S system by FOXO3a, regulates neuroendocrine hormones to modulate the energy homeostasis, thus highlights a new brain-adipose feedback axis in energy metabolism.


Assuntos
Cistationina beta-Sintase/metabolismo , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina , Obesidade/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Animais , Células Cultivadas , Hormônio Liberador da Corticotropina/metabolismo , Cistationina beta-Sintase/genética , Modelos Animais de Doenças , Metabolismo Energético , Proteína Forkhead Box O3/metabolismo , Sulfeto de Hidrogênio , Leptina/sangue , Camundongos , Obesidade/sangue , Obesidade/induzido quimicamente , Ratos , Tireotropina/sangue , Hormônio Liberador de Tireotropina/metabolismo , Tiroxina/sangue
9.
Bioanalysis ; 10(1): 47-58, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29239660

RESUMO

AIM: In order to assist and support early diagnosis of acute myocardial infarction (AMI), suspension array technology was established for multiplexed, rapid and accurate measurement of AMI biomarkers in serum samples. Methodology & results: It was developed by coating AMI biomarkers on distinguishable microbeads and competing with free biomarkers for complementary antibodies. The limits of detection of three AMI biomarkers were 2.5- to 50-times lower than that of the previous methods and the working ranges were four to five orders of magnitude. Accuracy and stability also met satisfying acceptance criteria in both of the intra- and interbatch testing. The variation coefficients and relative standard deviations were all less than 10%. CONCLUSION: Suspension array technology is completely applicable for requirements of rapid clinical diagnosis in serum sample.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Biomarcadores/sangue , Imunoensaio/métodos , Infarto do Miocárdio/diagnóstico , Doença Aguda , Humanos , Infarto do Miocárdio/sangue
10.
Antioxid Redox Signal ; 27(11): 742-753, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-28158956

RESUMO

AIMS: Hydrogen sulfide (H2S) plays an essential role in bone formation, in part, by inhibiting osteoclast differentiation, maintaining mesenchymal stem cell osteogenesis ability, or reducing osteoblast injury. We aimed to investigate the role of H2S in osteoblast function and its possible molecular target. RESULTS: In this study, we found that cystathionine γ-lyase (CSE) majorly contributed to endogenous H2S production in the primary osteoblast. Overexpressed CSE increased osteoblast differentiation and maturation with higher bone morphogenetic protein 2 and osteopontin expression, alkaline phosphatase activity, and calcium nodule formation; in contrast, knockdown of CSE had opposite effects. Runt-related transcript factor 2 (RUNX2) is required for osteoblast biologic function. CSE-H2S increased nuclear RUNX2 accumulation, DNA binding activity, and target gene transcription. Protein sulfhydration is a common signal by H2S. We confirmed that RUNX2 was also sulfhydrated by H2S. This chemical modification enhanced RUNX2 transactivation, which was blocked by dithiothreitol (DTT, sulfhydration remover). Mutation of two cysteine sites in the runt domain of RUNX2 abolished H2S-induced RUNX2 sulfhydration and transactivation. In a bone -fracture rat model, overexpressed CSE promoted bone healing, which confirmed the effect of CSE-H2S on osteoblasts. INNOVATION: CSE-H2S is a dominant H2S generation system in osteoblasts and promotes osteoblast activity by the RUNX2 pathway, with RUNX2 sulfhydration as a novel transactivation regulation. CONCLUSION: CSE-H2S sulfhydrated RUNX2 enhanced its transactivation and increased osteoblast differentiation and maturation, thereby promoting bone healing. Antioxid. Redox Signal. 27, 742-753.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Cistationina gama-Liase/metabolismo , Consolidação da Fratura , Fraturas Ósseas/terapia , Sulfeto de Hidrogênio/metabolismo , Osteoblastos/enzimologia , Animais , Diferenciação Celular , Cistationina gama-Liase/genética , Modelos Animais de Doenças , Fêmur/lesões , Fraturas Ósseas/genética , Fraturas Ósseas/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Masculino , Osteoblastos/citologia , Ratos , Ratos Sprague-Dawley
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