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1.
Emerg Med J ; 40(5): 320-325, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36351780

RESUMO

PURPOSE: Medical errors are a global concern, and specifically, EDs are at considerable risk for medical errors. Few studies focus on the healthcare provider's self-perceived medical errors in hospitals, let alone the ED. Hence, this study explored perceived medical errors and their correlation with work-related factors and personal distress among physicians in EDs in China. METHODS: From July 2018 to August 2018, a national web-based cross-sectional study was conducted. The link to the web-based questionnaire was posted on the emergency physicians' working platform, inviting Chinese licensed emergency physicians to participate anonymously in this survey. Our outcome of interest, medical errors, was investigated using self-reporting methods. Occupational stress was assessed using the Chinese version of the Effort-Reward Imbalance scale. The Patient Health Questionnaire, the subscale of the 10-item Positive and Negative Affect Schedule, the subscale of the validated Leiden Quality of Work Questionnaire and the 10-item Generalised Self-efficacy Scale were used to assess personal distress. Logistic regression analysis was used to determine factors significantly associated with perceived medical errors. RESULTS: A sample of 10 457 emergency physicians completed the survey. Almost half (43.63%) of physicians reported self-perceived medical errors during the previous 3 months. The rate of workplace verbal aggression, effort-reward imbalance and depressive symptoms were 81.81%, 78.39% and 35.71%, respectively. Medical errors were more likely to be reported among chief physicians, and those who reported the department was short-staffed for physicians, and who experienced workplace verbal aggression and intense work stress. Medical errors were significantly associated with negative affect and lower self-efficacy. CONCLUSION: Self-perceived medical errors are prevalent among physicians working in EDs and are associated with their workplace environment and personal distress. Targeted interventions are required to reduce physicians' workload and improve their working environment. Accounting for healthcare providers' distress is imperative for reducing the incidence of medical errors and improving their health.


Assuntos
Estresse Ocupacional , Médicos , Humanos , Estudos Transversais , Estresse Ocupacional/epidemiologia , Inquéritos e Questionários , China/epidemiologia , Erros Médicos
2.
Chem Soc Rev ; 51(2): 566-593, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34928283

RESUMO

The real-time, dynamic optical visualization of lesions and margins ensures not only complete resection of the malignant tissues but also better preservation of the vital organs/tissues during surgical procedures. Most imaging probes with an "always-on" signal encounter high background noise due to their non-specific accumulation in normal tissues. By contrast, activatable molecular probes only "turn on" their signals upon reaction with the targeted biomolecules that are overexpressed in malignant cells, offering high target-to-background ratios with high specificity and sensitivity. This review summarizes the recent progress of activatable molecular probes in surgical imaging and diagnosis. The design principle and mechanism of activatable molecular probes are discussed, followed by specific emphasis on applications ranging from fluorescence-guided surgery to endoscopy and tissue biopsy. Finally, potential challenges and perspectives in the field of activatable molecular probe-enabled surgical imaging are discussed.


Assuntos
Corantes Fluorescentes , Sondas Moleculares , Biópsia , Endoscopia , Imagem Molecular , Imagem Óptica
3.
J Clin Nurs ; 32(1-2): 106-114, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35037324

RESUMO

AIMS AND OBJECTIVES: To determine the prevalence and the associated factors of self-perceived medical errors among Chinese emergency department nurses. BACKGROUND: The emergency department is a place with a high incidence of medical errors. Studies about the occurrence and related influencing factors of medical errors among emergency nurses in China are very insufficient. DESIGN: A nationwide cross-sectional study. METHODS: A nationwide cross-sectional study was conducted from July 2018-August 2018. A total of 17,582 emergency department nurses from 31 provinces across China were eventually included in the analysis. Logistic regression is applied to examine the association of the independent variables with the perceived medical errors. The reporting of this study was compliant with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist for cross-sectional studies. RESULTS: Of 17,582 participating nurses, 4445 (25.28%) reported self-perceived medical errors in the past 3 months. Nurses who were serving as nurses-in-charge; who reported fair or bad physical health; who reported staff shortage; who were exposed to more verbal abuse at work; who experienced effort-reward imbalance; who reported more over-commitment; or who had depressive symptoms were more likely to report medical errors. Older age and female gender were protective factors. CONCLUSIONS: In this study, a quarter of the emergency nurses reported that they had made medical errors in the past 3 months. Self-perceived medical errors are associated with multiple domains of work-related factors and personal distress. Feasible measures should be taken to reduce nurses' workload, improve their working environment, monitor and minimise the occurrence of medical errors among emergency department nurses. RELEVANCE TO CLINICAL PRACTICE: Emergency nurses, who are the most frequently in contact with patients, play an important role in identifying risk factors and preventing medical errors. Identifying risk factors that may lead to medical errors in the medical environment from both internal and external aspects will help nursing practitioners, hospital administrators and policy makers to take timely preventive measures to reduce the occurrence of medical errors and reduce harm to patients.


Assuntos
Recursos Humanos de Enfermagem Hospitalar , Humanos , Feminino , Estudos Transversais , Serviço Hospitalar de Emergência , Erros Médicos , Carga de Trabalho , Inquéritos e Questionários
4.
Biochem Biophys Res Commun ; 596: 63-70, 2022 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-35114586

RESUMO

Owing to lacking protective effect of estrogen, OVX mice have higher risk of non-alcoholic fatty liver disease compared with normal female mice, when fed with high fat diet. Our study was to explore how estrogen protect against nonalcoholic steatohepatitis in female mice. We found that, lacking estrogen, M1 macrphages was activated and promoted steatohepatitis in obese OVX mice. And, ERα was responsible for estrogen to inhibit M1 macrphages activation and steatohepatitis. ERα knockdown aggravated M1 macrophages infiltration by transcriptionally upregulated its CCR2 expression. CCR2 antagonist effectively improved nonalcoholic steatohepatitis, ER stress and insulin resistance in ERα knockdown obese female mice. These results demonstrated ERα mediated M1 macrophages activation played a key role in nonalcoholic steatohepatitis.


Assuntos
Receptor alfa de Estrogênio/genética , Ativação de Macrófagos/genética , Macrófagos/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Animais , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/classificação , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ovariectomia , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Interferência de RNA , Receptores CCR2/genética , Receptores CCR2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
BMC Psychiatry ; 21(1): 353, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34261458

RESUMO

BACKGROUND: Effort-reward imbalance is an adverse psychological response to working conditions that has several negative effects on nurses. However, there is little research on effort-reward imbalance and its influencing factors among nurses in emergency departments. This study aimed to understand the current situation of effort-reward imbalance and explore its influencing factors among emergency department nurses in China. METHODS: From July to August 2018, a structured online questionnaire survey was conducted among emergency department nurses in China. Data were collected from emergency department nurses employed in hospitals providing pre-hospital care in China. The questionnaire consisted of sociodemographic characteristics, work-related factors and effort-reward imbalance. A descriptive analysis and a binary logistic regression were conducted to explore the effort-reward imbalance and its influencing factors among emergency department nurses. RESULTS: The study involved 17,582 emergency department nurses; notably, the prevalence of effort-reward imbalance was 59.66%. The participating nurses who were males, aged 25 to 34 years, whose educational level was a bachelor degree or above, who had a junior or above title, who had longer years of service, and who had suffered verbal or physical violence in the past year had a higher risk of effort-reward imbalance. Furthermore, the nurses with a high monthly income, who believed that the number of nurses met the department's demand had a lower risk of effort-reward imbalance. CONCLUSIONS: Effort-reward imbalance was prevalent among emergency department nurses in China. Measures such as adjusting the night shift frequency, increasing the number of nurses, raising salaries and reducing workplace violence should be considered to reduce the level of effort-reward imbalance.


Assuntos
Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , China , Estudos Transversais , Serviço Hospitalar de Emergência , Humanos , Satisfação no Emprego , Masculino , Recompensa , Inquéritos e Questionários
6.
J Cell Mol Med ; 23(5): 3616-3628, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30821074

RESUMO

The Hippo pathway is an evolutionarily conserved regulator of organ size and tumorigenesis that negatively regulates cell growth and survival. Whether the Hippo pathway regulates cell metabolism is unknown. Here, we report that in the nucleus of hepatocytes, Yes-associated protein(YAP)-the terminal effector of the Hippo pathway-directly interacts with sterol regulatory element binding proteins (SREBP-1c and SREBP-2) on the promoters of the fatty acid synthase (FAS) and 30-hydroxylmethyl glutaryl coenzyme A reductase (HMGCR), thereby stimulating their transcription and promoting hepatocyte lipogenesis and cholesterol synthesis. In diet-induced diabetic mice, either Lats1 overexpression or YAP knockdown protects against hepatic steatosis and hyperlipidaemia through suppression of the interaction between YAP and SREBP-1c/SREBP-2. These results suggest that YAP is a nuclear co-factor of SREBPs and that the Hippo pathway negatively affects hepatocyte lipogenesis by inhibiting the function of YAP-SREBP complexes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Fígado Gorduroso/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular/genética , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/genética , Dieta Hiperlipídica/efeitos adversos , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Fígado Gorduroso/genética , Hepatócitos/metabolismo , Via de Sinalização Hippo , Lipogênese/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas/genética , Ligação Proteica , Transdução de Sinais/genética , Proteínas de Sinalização YAP
7.
Plant J ; 95(6): 1004-1022, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29932274

RESUMO

The phytohormone auxin is essential for root development in plants. OsMADS25 is a homologue of the AGL17-clade MADS-box genes in rice. Despite recent progress, the molecular mechanisms underlying the regulation of root development by OsMADS25 are not well known. It is unclear whether OsMADS25 regulates root development via auxin signalling. In this study, we examined the role of OsMADS25 in root development and characterized the signalling pathway through which OsMADS25 regulates root system development in rice. OsMADS25 overexpression significantly increased, but RNAi gene silencing repressed primary root (PR) length and lateral root (LR) density. Moreover, OsMADS25 promoted LR development in response to NO3- . Further study showed that OsMADS25 increased auxin accumulation in the root system by enhancing auxin biosynthesis and transport, while also reducing auxin degradation, therefore stimulating root development. More importantly, OsMADS25 was found to regulate OsIAA14 expression directly by binding to the CArG-box in the promoter region of OsIAA14, which encodes an Aux/indole acetic acid (IAA) transcriptional repressor of auxin signalling. Elevated auxin levels and decreased OsIAA14 expression might lead to reduced OsIAA14 protein accumulation, as a mechanism to regulate auxin signalling. Therefore, our findings reveal a molecular mechanism by which OsMADS25 modulates root system growth and development in rice, at least partilly, via Aux/IAA-based auxin signalling.


Assuntos
Ácidos Indolacéticos/metabolismo , Proteínas de Domínio MADS/fisiologia , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/fisiologia , Proteínas de Plantas/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Proteínas de Domínio MADS/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Oryza/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais
8.
BMC Psychiatry ; 18(1): 70, 2018 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-29562903

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a common mental disorder worldwide, but now there is a lack of clinically effective assessment and management of MDD. In this study, we used technetium-99 m ethylcysteinate dimer ([99mTc]ECD) SPECT/CT to characterize the regional cerebral blood flow (rCBF) status of MDD patients, and to explore an objective image assessment model of MDD which is non- or minimally-invasive, convenient and accurate in a clinical setting. METHODS: The severity of MDD was assessed by three trained psychiatrists, based on scores obtained from HAMD and HAMA. [99mTc]ECD rCBF SPECT/CT was performed in 20 healthy controls and 74 unipolar MDD patients before receiving the treatment. The CT attenuation-corrected SPECT images data were automatically registered, analyzed simultaneously by 3D-SSP and eZIS. RESULTS: The mean score of HAMD and HAMA in the MDD patients was 25.49 ± 6.00, and 23.12 ± 5.83, respectively. There was a positive correlation between two scores. The MDD women had higher HAMD scores than MDD men. The decreased rCBF of MDD patients in frontal lobes (bilateral B11, B47 and right B4, B6, B10, B46), temporal lobe (right B21, B41, B42) and cingulated cortex (bilateral B24, B33), while their increased rCBF in occipital lobe (bilateral B17, B19 and left B18). Additionally, the depression severity was negatively correlated with decreased rCBF in left ventral anterior cingulate cortex B24, and was positively correlated with decreased rCBF in left inferior prefrontal gyrus B47 and increased rCBF in right associative visual cortex B19. The anxiety severity was negatively correlated with decreased rCBF in left subgenual cortex B25. CONCLUSIONS: Although the mechanism underlying the correlation is not yet fully understood, our findings indicated that the rCBF SPECT/CT may provide an objective assessment for MDD severity. It might be used monitoring therapeutic efficacy in the management of MDD.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Índice de Gravidade de Doença , Adulto , Córtex Cerebral/patologia , Circulação Cerebrovascular , Cisteína/análogos & derivados , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio , Lobo Temporal/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X
9.
Tumour Biol ; 39(4): 1010428317698364, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28381166

RESUMO

We explored the expression and function of miR-181d (microRNA-181d) in human pancreatic cancer. Quantitative real-time polymerase chain reaction was used to probe miR-181d expression in both pancreatic cancer cell lines and human pancreatic carcinoma. Pancreatic cancer cell lines, PANC-1 and AsPC-1 cells, were engineered to stably downregulate endogenous miR-181d through lentiviral transduction. The mechanistic effects of miR-181d downregulation on pancreatic cancer development were tested by proliferation, migration, fluorouracil chemosensitivity assays in vitro, and explant assay in vivo. Possible miR-181d downstream gene, NKAIN2 (Na+/K+ transporting ATPase interacting 2), was tested by dual-luciferase activity assay and quantitative real-time polymerase chain reaction. Functional involvement of NKAIN2 in miR-181d-regulated pancreatic cancer development was tested by small interfering RNA-mediated NKAIN2 knockdown in miR-181d-downregulated PANC-1 and AsPC-1 cells. MiR-181d was upregulated in both pancreatic cancer cell lines and human pancreatic carcinoma. Lentivirus-induced miR-181d downregulation decreased pancreatic cancer proliferation, migration, and fluorouracil resistance in vitro and inhibited the growth of cancer explant in vivo. NKAIN2 was directly targeted by miR-181d in pancreatic cancer. Small interfering RNA-mediated NKAIN2 knockdown reversed the inhibition of miR-181d downregulation on pancreatic cancer development. MiR-181d is aberrantly overexpressed in pancreatic cancer. Inhibiting miR-181d may suppress pancreatic cancer development, possibly through the inverse regulation on NKAIN2.


Assuntos
Genes Supressores de Tumor/fisiologia , Proteínas de Membrana/fisiologia , MicroRNAs/fisiologia , Neoplasias Pancreáticas/etiologia , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/genética , MicroRNAs/antagonistas & inibidores , Neoplasias Pancreáticas/prevenção & controle
10.
J Digit Imaging ; 28(1): 99-115, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25117512

RESUMO

Differentiation of malignant and benign pulmonary nodules is of paramount clinical importance. Texture features of pulmonary nodules in CT images reflect a powerful character of the malignancy in addition to the geometry-related measures. This study first compared three well-known types of two-dimensional (2D) texture features (Haralick, Gabor, and local binary patterns or local binary pattern features) on CADx of lung nodules using the largest public database founded by Lung Image Database Consortium and Image Database Resource Initiative and then investigated extension from 2D to three-dimensional (3D) space. Quantitative comparison measures were made by the well-established support vector machine (SVM) classifier, the area under the receiver operating characteristic curves (AUC) and the p values from hypothesis t tests. While the three feature types showed about 90% differentiation rate, the Haralick features achieved the highest AUC value of 92.70% at an adequate image slice thickness, where a thinner or thicker thickness will deteriorate the performance due to excessive image noise or loss of axial details. Gain was observed when calculating 2D features on all image slices as compared to the single largest slice. The 3D extension revealed potential gain when an optimal number of directions can be found. All the observations from this systematic investigation study on the three feature types can lead to the conclusions that the Haralick feature type is a better choice, the use of the full 3D data is beneficial, and an adequate tradeoff between image thickness and noise is desired for an optimal CADx performance. These conclusions provide a guideline for further research on lung nodule differentiation using CT imaging.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Bases de Dados Factuais/estatística & dados numéricos , Humanos , Imageamento Tridimensional/métodos , Análise de Componente Principal , Curva ROC , Sensibilidade e Especificidade
11.
Int J Inj Contr Saf Promot ; 31(1): 3-11, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37526366

RESUMO

Left-turn waiting area (LWA) is an innovative traffic design that is popularly applied to improve the traffic capacity of signalized intersections in China. The traffic safety impacts of the LWA, however, have not been fully discussed in previous studies. Thus, the study aims to evaluate the safety performance of the LWA by means of the traffic conflict technique. A field investigation was conducted to collect the post-encroachment time (PET) of conflicts and relevant variables at the signalized intersections in Jinhua, China. The Chi-square and two sample t-tests were adopted to examine the difference in conflict distribution between the intersections with and without LWA. The random parameter ordered logit model was employed to identify the factors contributing to the risks of vehicular collisions. Results indicate that (1) intersections with LWA are generally associated with more merging conflicts; (2) there are no significant discrepancies in the PET values between intersections with and without LWA; and (3) factors such as the number of left-turn lanes, number of receiving lanes, conflict type, vehicle type, driving direction, stopping outside LWA and overtaking behavior are identified to significantly impact the traffic conflicts. The findings serve to develop the countermeasures to ensure the safe operation of LWA.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Acidentes de Trânsito/prevenção & controle , Segurança , Planejamento Ambiental , Modelos Logísticos , China
12.
J Safety Res ; 89: 262-268, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38858050

RESUMO

INTRODUCTION: Speeding behavior is a major threat to road traffic safety, which can increase crash risks and result in severe injury outcomes. Although several studies have been conducted to analyze speeding crashes and relevant influential factors, the heterogeneity of variables has not been fully explored. Based on the traffic crash data extracted from the Crash Report Sampling System, the study aims to identify the factors that influence speeding driving with the consideration of variable heterogeneity. METHOD: Quasi-induced exposure technique is adopted to identify the disparities in the propensities of speeding for various driving cohorts. The random parameter logit model with heterogeneity in means is employed to examine the factors impacting speeding behavior. RESULTS: Results indicate that: (a) driving cohorts such as young drivers, male drivers, passenger cars, and pickups appear to have higher propensities of engaging in speeding driving; (b) the propensity of speeding is higher when the driver is drinking, distracted, changing lanes, negotiating a curve, driving in lighted condition, and on curved roads; and (c) the random parameter logit model with heterogeneity in means has better performance as opposed to that without heterogeneity in means. CONCLUSIONS: Speeding behavior can be influenced by various factors in terms of driver-vehicle characteristics, physical condition, driving actions, and environmental conditions. PRACTICAL APPLICATIONS: The findings could serve to develop effective countermeasures to reduce speeding behavior and improve traffic safety.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Condução de Veículo/estatística & dados numéricos , Masculino , Acidentes de Trânsito/estatística & dados numéricos , Acidentes de Trânsito/prevenção & controle , Adulto , Modelos Logísticos , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Assunção de Riscos
13.
Materials (Basel) ; 17(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893758

RESUMO

Negative thermal expansion (NTE) ceramics Sm0.85Zn0.15MnO3 (SZMO) and ZrMgMo3O12 (ZMMO) were selected to prepare Sm0.85Zn0.15MnO3-ZrMgMo3O12/Al-20Si (SZMO-ZMMO/Al-20Si) composites using ball milling and vacuum heating-press sintering processes in this study. The synergistic effect of the SZMO and ZMMO NTE ceramic reinforcements on the microstructure, mechanical properties, and coefficient of thermal expansion (CTE) of the composites was investigated. The results show that the processes of ball milling and sintering did not induce the decomposition of SZMO or ZMMO NTE ceramic reinforcements, nor did they promote a reaction between the Al-20Si matrix and SZMO or ZMMO NTE ceramic reinforcements. However, the excessive addition of SZMO and ZMMO NTE ceramics led to their aggregation within the composite. Adding a small amount of SZMO in combination with ZMMO effectively increased hardness and yield strength while reducing CTE in the Al-20Si alloy. The improvement in strength was primarily provided by SZMO, while the inhibition effect on CTE was primarily provided by ZMMO. An evaluation parameter denoted as α was proposed to evaluate the synergy effects of SZMO and ZMMO NTE ceramic reinforcements on the mechanical properties and CTE of the composites. Based on this parameter, among all composites fabricated, adding 2.5 vol% SZMO NTE ceramic and 10 vol% ZMMO NTE ceramic resulted in an optimal balance between CTE and strength for these composites with a compressive yield strength of 349.72 MPa and a CTE of 12.55 × 10-6/K, representing a significant increase in yield strength by 79.20% compared to that of Al-20Si alloy along with a notable reduction in CTE by 26.44%.

14.
Cancer Lett ; 581: 216511, 2024 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-38013049

RESUMO

Deciphering the mechanisms behind how T cells become exhausted and regulatory T cells (Tregs) differentiate in a tumor microenvironment (TME) will significantly benefit cancer immunotherapy. A common metabolic alteration feature in TME is lipid accumulation, associated with T cell exhaustion and Treg differentiation. However, the regulatory role of free fatty acids (FFA) on T cell antitumor immunity has yet to be clearly illustrated. Our study observed that palmitic acid (PA), the most abundant saturated FFA in mouse plasma, enhanced T cell exhaustion and Tregs population in TME and increased tumor growth. In contrast, oleic acid (OA), a monounsaturated FFA, rescued PA-induced T cell exhaustion, decreased Treg population, and ameliorated T cell antitumor immunity in an obese mouse model. Mechanistically, mitochondrial metabolic activity is critical in maintaining T cell function, which PA attenuated. PA-induced T cell exhaustion and Treg formation depended on CD36 and Akt/mTOR-mediated calcium signaling. The study described a new mechanism of PA-induced downregulation of antitumor immunity of T cells and the therapeutic potential behind its restoration by targeting PA.


Assuntos
Ácido Palmítico , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Ácidos Graxos , Ácido Palmítico/farmacologia , Linfócitos T Reguladores , Serina-Treonina Quinases TOR , Microambiente Tumoral
15.
PLoS One ; 18(2): e0279387, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36730326

RESUMO

In quasi-induced exposure (QIE) theory, the presence of hazardous driving action is the typical determinant of the driver's responsibility for a crash. However, there is a lack of effort available to analyze the impacts of hazardous actions on the QIE estimate, which may result in estimation bias. Thus, the study aims to explore the difference in QIE to crashes involving various hazardous driving actions. Chi-square test is conducted to examine the consistency of non-responsible party distributions among the crashes involving various hazardous actions. Multinomial logit model and nested logit model are employed to identify the disparities of contributing factors to the actions. Results indicate that: 1) the estimated exposures appear to be inconsistent among the crashes with different hazardous actions, 2) driving cohorts have differential propensities of performing various hazardous actions, and 3) factors such as driver-vehicle characteristics, time, area, and environmental condition significantly affect the occurrence of hazardous actions while the directions and magnitude of the effects show great disparities for various actions. It can be concluded that the QIE estimates are significantly different for crashes involving various hazardous actions, which serves to highlight the importance of clarifying the specific hazardous actions for responsibility assignment in QIE theory.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Modelos Logísticos , Viés
16.
Int J Inj Contr Saf Promot ; 29(4): 556-565, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35763696

RESUMO

Distracted driving can pose great risks to road traffic safety. Although there is a rich body of literature devoted to identifying the statistical association between distracted driving and crash risks, few are available to examine the causal effect mechanism of distracted driving. Thus, the study attempts to conduct the causal mediation analysis to reveal the impact mechanism of distracted driving on crash injury risks, in which various hazardous driving actions are used as the mediators between driver distraction and crash injuries. Sensitivity analysis is also carried out to validate the underlying assumption of causal mediation analysis. The analytic results indicate that 1) distracted driving can lead to a higher likelihood of hazardous driving actions such as failing to yield, disobeying traffic control devices, driving left of lane center, and failing to stop in assured clear distance, 2) both the driver distraction and hazardous actions are the contributory factors to the severe crash injuries, and 3) distracted driving is identified to have significant mediation effects on crash injury risks. The study confirms the causal mediation effects of distracted driving on crash injury risks, which can serve to propose specific safety countermeasures to mitigate the crash injury risks.


Assuntos
Condução de Veículo , Direção Distraída , Humanos , Acidentes de Trânsito , Análise de Mediação , Probabilidade
17.
Accid Anal Prev ; 174: 106756, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35728451

RESUMO

Analyzing speed mean and variance is vital to safety management in urban roadway networks. However, modeling speed mean and variance on structured roads could be influenced by the spatial effects, which are rarely addressed in the existing studies. The inadequacy may lead to biased conclusions when considering vehicle speed as a surrogate safety measure. The current study focuses on developing a Bayesian modeling approach with three types of spatial effects, i.e., spatial correlation, spatial heterogeneity, and spillover effect. To capture the spatial correlation, the study employs the intrinsic conditional autoregressive (ICAR) models, spatial lag models (SLM), and spatial error models (SEM). Spatial heterogeneity and spillover effect are considered by the random parameters approach and spatially lagged covariates (SLCs). Speed data are collected from the float cars running on 134 urban arterials in Chengdu, China. The results indicate that the random parameters ICAR model with SLCs (RPICAR-SLC) outperforms others in terms of goodness-of-fit, accuracy, and efficiency for modeling speed mean, while the random parameters ICAR model (RPICAR) is the best for modeling speed variance. Moreover, RPICAR-SLC and RPICAR models are beneficial to address spatial correlation of residuals, explaining the unobserved influence among the observations, and are less likely to cause biased or overestimated parameters. The study also discusses how traffic conditions, road characteristics, traffic management strategies, and facilities on roadway networks influence speed mean and variance. The findings highlight the importance of multi-type spatial effects on modeling speed mean and variance along the structured roadways.


Assuntos
Acidentes de Trânsito , Planejamento Ambiental , Teorema de Bayes , Humanos , Complexo Ferro-Dextran , Modelos Estatísticos , Segurança
18.
Front Oncol ; 12: 923683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992819

RESUMO

Background: Intrathyroid thymic carcinoma (ITTC) is a rare malignancy of the thyroid gland with histological and immunophenotypic resemblance to thymic carcinoma. Surgery combined with adjuvant radiotherapy improves the survival of patients with ITTC. However, for patients with extensive metastases, there is currently no effective treatment. Chemotherapy is an option but has not demonstrated improved patient survival. Methods and results: A female patient presented with metastases to the pleura, lung, and bone 16 years after surgery for ITTC. As radiotherapy and chemotherapy failed to control the recurrent disease, lenvatinib treatment was initiated. After 3 months, positron emission tomography/computed tomography showed a substantial reduction of all metastatic lesions and decreased tumor metabolism. The patient continues to receive lenvatinib and remains well and symptom-free. Conclusion: For patients with ITTC who have progressive, life-threatening metastases, lenvatinib represents a valuable salvage therapy that may offer a sustained reduction in tumor burden and maintenance of quality of life.

19.
BMJ Open ; 12(6): e052239, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676005

RESUMO

OBJECTIVES: Reconstructing the primary healthcare system is the focus of the new round of Chinese health reform. Nevertheless, there have been few studies focusing on the strengthening of primary healthcare in Chinese health system. DESIGN: This study was a longitudinal observational study. PRIMARY AND SECONDARY OUTCOME MEASURES: The data of this study came from China Health Statistical Yearbook (2009-2018). We evaluated the development of primary healthcare based on the absolute values of health resources allocation and health service provision and evaluated the status of primary healthcare throughout the health system based on the composition ratios of the indicators across the health system. The Cochran-Armitage trend test and linear trend test were used to identify the indicators' trends over time. RESULTS: From 2009 to 2018, the amounts of health resources allocation and health service provision of Chinese primary healthcare institutions showed a significant upward trend (p<0.001). However, compared with the indicators in 2009, excepting that the proportion of grants from the government in the whole health system has an upward trend, the proportions of other indicators had an escalating trend in 2018 by 3.66% for practicing (assistant) physicians, by 2.69% for nurses, by 3.99% for total revenues, by 5.87% for beds, by 8.39% for outpatient visits. CONCLUSION: The primary healthcare system has developed rapidly, but its development speed lagged behind the entire health system, resulting in the weakening of its actual functions, which is not in line with the goal of health reform. The government should be more aware of the importance of primary healthcare at all levels of local governments and ensure adequate financial input.


Assuntos
Atenção à Saúde , Reforma dos Serviços de Saúde , China , Serviços de Saúde , Humanos , Atenção Primária à Saúde
20.
Polymers (Basel) ; 14(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35808695

RESUMO

Ultrasonic welding (UW) of polymeric composites is significant in automobile industry; however, maintaining the perfect contact condition between workpieces is a great concern. In this study, effect of preloading and welding pressure on strengths of UWed 2.3-mm-thick short carbon fiber reinforced nylon6 (Cf/PA6) joints with poor contact between workpieces was investigated through stress simulation and energy dissipation at the faying interface. Results showed the application of preloading can increase the strength of normal joint by 18.7% under optimal welding parameters. Gaps between upper and lower workpieces decreased the joint strength significantly, especially for gaps greater than 1.5 mm. Preloading improved the strengths of the joints with gaps remarkably, where the strength of joints with 1.5 mm gap recovered to 95.5% of that the normal joint. When combining the weld nugget evolution, stress-deformation simulation during UW, and ultrasonic vibration transmission analysis, the improvement mechanism of the joint under preloading was mainly because the preloading compacted the contact between workpieces, which favored the energy transmission at faying interface.

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