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1.
Ergonomics ; : 1-17, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37988319

RESUMO

Frequent extreme cold events in recent years have brought serious threats to outdoor workers and rescuers. Changes in ambient temperature are associated with altered cardiac autonomic function. The study aims to investigate heart rate variability (HRV) and its relationship to other physiological parameters under extreme cold exposures. Twelve males underwent a 30-min preconditioning phase in a neutral environment followed by a 30-min cold exposure (-5, -10, -15, and -20 °C). Time-domain indexes(meanRR, SDNN, RMSSD, and pNN50), frequency domain indexes [Log(HF), Log(LF), and low frequency/high frequency (LF/HF)], parasympathetic nervous system (PNS), and sympathetic nervous system (SNS) were analysed. Results showed all HRV indexes of four cold exposures were significant. The decrease in temperature was accompanied by progressive PNS activation with SNS retraction. SDNN was the most sensitive HRV index and had good linear relationships with blood pressure, pulse, and hand temperature. The results are significant for formulating safety protection strategies for workers in extremely cold environments.Practitioner Summary: This study investigated heart rate variability (HRV) in 12 males during a 30-min cold exposure (-5, -10, -15, and -20 °C). Results showed all HRV indexes of four cold exposures were significant. The decrease in temperature was accompanied by progressive PNS activation with SNS retraction. SDNN was the most sensitive HRV index and had good linear relationships with blood pressure, pulse, and hand temperature.

2.
J Therm Biol ; 112: 103484, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36796926

RESUMO

Human thermal comfort is relevant to human life comfort and plays a pivotal role in occupational health and thermal safety. To ensure that intelligent temperature-controlled equipment can deliver a sense of cosiness to people while improving its energy efficiency, we designed a smart decision-making system that sets the thermal comfort adjustment preference as a label, reflecting both the human body's thermal feeling and its acceptance of the thermal environment. By training a series of supervised learning models underpinned by environmental and human features, the most appropriate adjustment mode in the current environment was predicted. To bring this design into reality, we tried six supervised learning models, and then, by comparison and evaluation, we identified that the Deep Forest's performance was the best. The model takes into account objective environmental factors and human body parameters. In this way, it can achieve high accuracy in application and good simulation and prediction results. The results can provide feasible references for feature selection and model selection in further research with the aim of testing thermal comfort adjustment preference. The model can provide recommendations for the thermal comfort preference in a specific place at a particular time, as well as guidance on human thermal comfort preference and thermal safety precautions in specific occupational groups.


Assuntos
Aprendizado de Máquina Supervisionado , Sensação Térmica , Humanos , Temperatura , Simulação por Computador
3.
Artigo em Inglês | MEDLINE | ID: mdl-35805501

RESUMO

Power grid outdoor workers are usually exposed to hot environments and could suffer the threats to occupational health and safety like heat strain and injury. In order to predict and assess the thermophysiological responses of grid workers in the heat, the clothing thermal insulation of grid worker ensembles was measured by a thermal manikin and a multi-segment human bioheat model was employed to evaluate the thermophysiological response parameters of grid workers such as core temperature, skin temperature and sweat loss. The results show that working in a hot environment can cause a obvious increase in core temperature and skin temperature of grid workers, and the acceptable maximum working time of grid workers varies greatly in different hot environments. A reasonable work organization strategy can effectively decrease the core temperature and sweat loss, increasing the duration of acceptable maximum working time for grid workers. This study is helpful to assess heat-related risks of grid workers and support power grid companies to rationalize work organization strategies and personal protection guidelines.


Assuntos
Transtornos de Estresse por Calor , Temperatura Alta , Transtornos de Estresse por Calor/prevenção & controle , Humanos , Manequins , Temperatura Cutânea , Suor , Sudorese
4.
J Therm Biol ; 98: 102933, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34016355

RESUMO

Extremely cold events have occurred more frequently in the past few years. People exposed to extremely cold exposure could suffer the threats of human health and safety like cold stress and injury. This study aims to investigate human physiological responses of exposure to extremely cold environments and the moment of temperature step. The experiments of 12 subjects exposed to three different cold exposure conditions (-5 °C, -10 °C, -15 °C) were carried out in a climate chamber. Most critical physiological parameters, including the core temperature, local skin temperature, blood pressure, heart rate, respiration rate and blood oxygen saturation, were measured to evaluate human physiological responses. In the particular short term study, the results show that the local skin temperature and blood pressure are the most significant indexes for evaluating the risk of cold strain in extremely cold environment. The finger temperature is a critical index of hand and finger flexibility, and it will lead to serious injuries and reduced manual performance when exposed to below -5 °C for more than 20 min. The high physiological strain at the very beginning moment of cold exposure can significantly affect the ability to make correct judgment and action, and it is suggested that the personnel adapt for 3 min after entering into the extremely cold environment to stabilize physiological parameters and thus enhancing the safety and occupational performance. The experimental data of this study is also of great significance for the development and validation of thermophysiological models.


Assuntos
Frio Extremo , Adulto , Pressão Sanguínea , Temperatura Corporal , Dedos , Frequência Cardíaca , Humanos , Masculino , Oxigênio/sangue , Taxa Respiratória , Pele , Adulto Jovem
5.
Physiol Behav ; 230: 113296, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33352146

RESUMO

Many jobs like outdoor work and emergency rescue have to be exposed to extremely cold environments. The combined effects of the cold exposure and work intensity on human cognitive performance remain unclear. In this paper, the experiments of six Chinese young men exposed to an extremely cold environment (-10 °C) were conducted in a climatic chamber. The work intensity level was graded according to the metabolic rate corresponding to three walking speeds. Nine cognitive functions and one perceived were recorded to evaluate the subjects' cognitive performance, including NCTB (seven items), Stroop, and RPE were measured. The increase of workload from moderate to high could lead to the acceleration of fatigue speed and the aggravation of fatigue degree 5 min earlier. Moderate work intensity is a noteworthy work level in extremely cold environment, which is an inflection point in the impact of fatigue and cognitive levels. The manual dexterity significantly increases by the workload intensity, and the high work intensity makes the hands more dexterous (29% increase). Extremely cold environment has a significant effect on short-term memory (decreased 33%). The selective attention was reduced by 16% in the extremely cold environment. With the moderate work intensity in extremely cold environment, the perceived judgment response speed would decrease. The combined effects of the extremely cold environment and the workload on the cognitive functions of psychomotor ability and attention or sensorimotor speed should be paid more attention to.


Assuntos
Mãos , Carga de Trabalho , Cognição , Temperatura Baixa , Humanos , Masculino , Memória de Curto Prazo , Tempo de Reação
6.
Oncol Lett ; 20(1): 235-247, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32565950

RESUMO

The transfer and development of chronic hepatitis B virus (HBV) infection is associated with the T cell immune response, therefore investigating the key regulators of cell immune response is needed to improve chronic HBV treatment. Blood samples from patients with chronic HBV infection were used to confirm the correlation between HBV infection stage and CD160 receptor expression levels in CD8+ T cells, the CD8+ T cells are used to research the mechanism of T cell immune response modulation, moreover, C3H/HeN mice with reduced CD160 expression levels were used to investigate the association between long non-coding (lnc)RNA-CD160 and HBV infection. Long non-coding (lnc)RNA-CD160 and histone-modification enzyme gene histone deacetylase 11 (HDAC11) expression levels were negatively associated with CD160 expression. lncRNA-CD160 can inhibit the secretion of IFN-γ and TNF-α through HDAC11 recruitment and bind to HDAC11 to form a complex on the promoters of IFN-γ and TNF-α. The HDAC11, IFN-γ and TNF-α form a complex and enhance the methylation of H3K9Me1, chromatin changes into the heterochromatin and the transcription of IFN-γ and TNF-α is blocked; moreover, the HDAC11/IFN-γ/TNF-α complex can also inhibit the secretion of IFN-γ and TNF-α in CD160- CD8+ T cells and suppresses the function of CD8+ T cells. Furthermore, small interfering RNA targeting lncRNA-CD160 can block HBV infection progression. lncRNA-CD160 acts as an immune suppressive factor and is expressed at a high level in peripheral blood CD8+ T cells of HBV infected patients. Furthermore, high expression levels of lncRNA-CD160 can contribute to the inhibition of IFN-γ and TNF-α secretion in CD8+ T cells and decrease the immune response of CD8+ T cells. Therefore, lncRNA-CD160 may become a new target for immunotherapy of chronic HBV infection in the future and may provide a new therapeutic strategy for the treatment of HBV infection.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31936352

RESUMO

In recent years, concerns about the safety of laboratories have been caused by several serious accidents in school laboratories. Gas leaks in the laboratory are often difficult to detect and cause serious consequences. In this study, a comprehensive model based on the Bayesian network is established for the assessment of the gas leaks evolution process and consequences in school laboratories. The model can quantitatively evaluate the factors affecting the probability and consequences of gas leakage. The results show that a model is an effective tool for assessing the risk of gas leakage. Among the various factors, the unsafe behavior of personnel has the greatest impact on the probability of gas leakage, and the concentration of toxic and harmful gases is the main factor affecting the consequences of accidents. Since the probability distribution of each node is obtained based on the experience of experts, there is a deviation in the quantitative calculation of the probability of gas leakage and consequences, but does not affect the risk analysis. This study could quantitatively assess the probability and consequences of gas leakage in the laboratory, and identify vulnerabilities, which helps improve the safety management level of gas in the school laboratory and reducing the possibility of gas leakage posing a threat to personal safety.


Assuntos
Acidentes , Gás Natural , Instituições Acadêmicas , Teorema de Bayes , Laboratórios , Medição de Risco , Gestão da Segurança
8.
Exp Ther Med ; 18(6): 4209-4220, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31777531

RESUMO

Although it is known that Phenazine biosynthesis-like domain-containing protein (PBLD) expression is downregulated in hepatocellular carcinoma (HCC), its biological function is unclear. Additionally, no agents capable of upregulating PBLD exist. In the current study, the relationship between PBLD and HCC was analyzed using clinicopathological specimens. A HCC cell model, microarray analysis and an animal model were used to verify the therapeutic effect of cedrelone on HCC. The present study demonstrated that PBLD inhibited HCC progression. Furthermore, the present study revealed that cedrelone possessed treated-HCC capabilities via targeted PBLD overexpression. The epithelial-mesenchymal transition phenotype and growth rate were inhibited and the apoptosis ratio was promoted by cedrelone following PBLD overexpression. The Ras and Ras-proximate-1 signaling pathways were also determined to be regulated by cedrelone via PBLD activation in HCC. PBLD may therefore be an independent predictor of HCC progression and a novel target for HCC treatment. Additionally, the PBLD activator, cedrelone, may be a potential drug for HCC treatment in the future.

9.
Medicine (Baltimore) ; 97(28): e11295, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29995763

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common cancers and the second leading cause of cancer-related deaths in men worldwide. Surgical resection of HCC remains the mainstay treatment procedure. As a result of hepatitis viral infection, the postoperative survival outcome in patients with HCC is not satisfactory. Recently, studies have reported that due to its treatment effect on hepatitis infection, pegylated interferon (Peg-IFN)-based therapy could improve the survival outcome after the treatment of hepatitis-related HCC. However, the postoperative effect of this regimen on the survival outcomes in patients with hepatitis-related HCC remains debatable. The present study conducted a meta-analysis to evaluate the effects of adjuvant Peg-IFN-based therapy on the survival outcomes in patients with hepatitis-related HCC after the curative treatment. METHODS: A systematic search was conducted to identify studies on the survival outcomes in patients with hepatitis-related HCC after a curative treatment with adjuvant Peg-IFN. PubMed, EmBase, and Cochrane Library databases were searched until September 20, 2017. The retrieved studies were independently assessed by 2 reviewers, to identify the potentially eligible studies and extract data of interest. STATA software (Version 10.0, STATA Corporation, College Station, Texas) software was used for all statistical analyses. RESULTS: The pooled results showed that adjuvant Peg-IFN-based therapy improved the 3- and 5-year recurrence-free survival (RFS) rates of patients with hepatitis-related HCC (3-year RFS, HR = 0.80; 95% CI: 0.64-0.99, P = .04; P = .81 for heterogeneity; 5-year RFS, HR = 0.82; 95% CI: 0.67-0.99, P = .04; P = .84 for heterogeneity). For the 5-year overall survival (OS) outcomes of Peg-IFN therapy for hepatitis-related HCC after the curative treatment, the pooled results showed a significant difference between the 2 groups (HR = 0.67; 95% CI: 0.47-0.97, P = .03; P = .99 for heterogeneity). CONCLUSIONS: Adjuvant Peg-IFN-based therapy could improve the RFS and OS outcomes in patients after curative treatment of hepatitis-related HCC, with no severe adverse effects.


Assuntos
Carcinoma Hepatocelular , Hepatectomia , Hepatite Viral Humana/complicações , Interferon-alfa/farmacologia , Neoplasias Hepáticas , Polietilenoglicóis/farmacologia , Antivirais/farmacologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Quimioterapia Adjuvante/métodos , Hepatectomia/métodos , Hepatectomia/mortalidade , Humanos , Interferon alfa-2 , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Proteínas Recombinantes/farmacologia , Análise de Sobrevida
10.
Oncol Lett ; 14(5): 5400-5408, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29098031

RESUMO

Pancreatic cancer rapidly acquires resistance to chemotherapy resulting in its being difficult to treat. Gemcitabine is the current clinical chemotherapy strategy; however, owing to gemcitabine resistance, it is only able to prolong the life of patients with pancreatic cancer for a limited number of months. Understanding the underlying molecular mechanisms of gemcitabine resistance and selecting a suitable combination of agents for the treatment of pancreatic cancer is required. Astaxanthin (ASX) is able to resensitize gemcitabine-resistant human pancreatic cancer cells (GR-HPCCs) to gemcitabine. ASX was identified to upregulate human equilibrative nucleoside transporter 1 (hENT1) and downregulate ribonucleoside diphosphate reductase (RRM) 1 and 2 to enhance gemcitabine-induced cell death in GR-HPCCs treated with gemcitabine, and also downregulates TWIST1 and ZEB1 to inhibit the gemcitabine-induced epithelial-mesenchymal transition (EMT) phenotype in GR-HPCCs and to mediate hENT1, RRM1 and RRM2. Furthermore, ASX acts through the hypoxia-inducible factor 1α/signal transducer and activator of transcription 3 signaling pathway to mediate TWIST1, ZEB1, hENT1, RRM1 and RRM2, regulating the gemcitabine-induced EMT phenotype and gemcitabine-induced cell death. Co-treatment with ASX and gemcitabine in a tumor xenograft model induced by GR-HPCCs supported the in vitro results. The results of the present study provide a novel therapeutic strategy for the treatment of gemcitabine-resistant pancreatic cancer.

11.
Sci Total Environ ; 609: 1041-1048, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-28787778

RESUMO

Studies examining the relation between climate and human conflict often focus on the role of temperature and have diverging views on the significance of other climatic variables. Using a 6-year (from 2009 to 2014) dataset of crime statistics collected in a medium size city of Tangshan in China, we find strong, positive correlations between temperature and both violent and property crimes. In addition, relative humidity is also positively correlated with Rape and Minimal Violent Robbery (MVR). The seasonal cycle is a significant factor that induces good correlations between crime rates and climatic variables, which can be reasonably explained by the Routine Activity theory. We also show that the combined impacts of temperature and relative humidity on crime rates can be reasonably captured by traditional heat stress indices. Using an ensemble of CMIP5 global climate change simulations, we estimate that at the end of the 21st century the rates of Rape (violent crime) and MVR (property crime) in Tangshan will increase by 9.5±5.3% and 2.6±2.1%, respectively, under the highest emission scenario (Representative Concentration Pathway 8.5). The gross domestic product (GDP) is also shown to be significantly correlated with MVR rates and the regression results are strongly impacted by whether GDP is considered or not.


Assuntos
Mudança Climática , Crime , China , Produto Interno Bruto , Humanos , Umidade , Temperatura
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