The Impact of COVID-19 on the Mental-Emotional Wellbeing of Primary Healthcare Professionals: A Descriptive Correlational Study

The present study aimed to examine work environment related factors and frontline primary healthcare profes-sionals’mental-emotional wellbeing during the COVID-19 pandemic in school communities of Hong Kong.A total of 61(20%)school health nurses(frontline primary healthcare professionals)participated in a cross-sec-tional online survey from March to June 2020.Outcomes of mental-emotional health were measured using the Mental Health Continuum-Short Form(14-item scale with three subscales related to emotional,social and psychological wellbeing);the Perceived Stress Scale(10-item scale with two subscales related to perceived help-lessness and lack of self-efficacy);and the Coping Orientation to Problems Experienced Inventory(Brief COPE),a 28-item inventory with two subscales related to adaptive and maladaptive strategies.Almost half(42.6%)of par-ticipants experienced mental health problems.Those employed in government subsidized schools had signifi-cantly lower scores in mental health wellbeing than those who worked in private schools.Factors relating to increased mental health problems included lack of emotional support,inadequate training relating to infection prevention and control measures,disengagement and self-blame.A variety of factors influencing school health nurses’social,emotional and psychological wellbeing in their work environment during the COVID-19 pandemic were also reported.The mental-emotional wellbeing of school nurses may relate to their subjective feeling of lone-liness as participants were the sole frontline primary healthcare professional working in the school community during the COVID-19 pandemic.Studyfindings provide relevant evidence for management teams to build a cul-ture of psychological and social support into workplace policies and procedures.Continuous staff development and adequate social support are important to promote the mental-emotional wellbeing of primary healthcare pro-fessionals in school communities as they play a significant role in safeguarding resources during pandemics.

Evaluation of Well Spacing for Primary Development of Fractured Horizontal Wells in Tight Sandstone Gas Reservoirs

Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage mechanisms.In this study,the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage experiments.On the basis of these experiments,a numerical simulation model(based on the special seepage mechanism)and an inverse dynamic reserve algorithm(with different equivalent drainage areas)were developed.The well spacing ranges of Classes I,II,and III wells in the Q gas field are determined to be 802–1,000,600–662,and 285–400 m,respectively,with their average ranges as 901,631,and 342.5 m,respectively.By considering both the pairs of parallel well groups and series well groups as examples,the reliability of the calculation results is verified.It is shown that the combination of the two models can reduce errors and provide accurate results.

A Comparative Study About the Neuroprotective Effects of EPA-Enriched Phosphoethanolamine Plasmalogen and Phosphatidylethanolamine Against Oxidative Damage in Primary Hippocampal Neurons

s Oxidative stress is involved in the progression of neurodegenerative diseases.Previous evidences showed that plasma-logens could improve neurodegenerative diseases.In this study,we investigated the function of phosphoethanolamine plasmalogens enriched with EPA(EPA-pPE)and phosphatidylethanolamine enriched with EPA(EPA-PE)on oxidative damage prevention after hy-drogen peroxide(H2O2)and tert-butylhydroperoxide(t-BHP)challenge in primary hippocampal neurons.Results showed that neurons pretreated with EPA-pPE and EPA-PE demonstrated the ability to alleviate oxidative damage,which was proved by the in-creased cell viability.Moreover,the shape and number of neurons were more similar to those of the control group.Antioxidant acti-vity,apoptosis,as well as TrkB/ERK/CREB signaling pathway were investigated to explore the mechanisms.The results suggested that EPA-PE was superior to EPA-pPE in regulating mitochondrial apoptosis.EPA-pPE was more prominent than EPA-PE in upre-gulating TrkB/ERK/CREB signaling pathway.Phospholipids with EPA exerted neuroprotective effects via inhibiting oxidative stress,suppressing apoptosis,and regulating TrkB/ERK/CREB signaling pathway.Therefore,the results provide a scientific basis for utili-zation of phospholipids enriched with EPA on the treatment of neurodegenerative disease.

The Role of Serum Ceruloplasmin and Oxidative Stress Markers in Primary Open Angle Glaucoma

Purpose: The study aimed at evaluation of the role of ceruloplasmin (A protein involved in iron homeostasis and can inactivate free radicals) and other oxidative stress markers as superoxide dismutase (SOD), malondialdehyde (MDA) and catalase activity (CAT) in primary open angle glaucoma (POAG). Methods: This observational case control study included 90 persons divided into 3 equal groups: group A of 30 normal persons as a control group, group B of 30 patients of untreated (POAG) (firstly diagnosed) by the clinical characters including measuring intraocular pressure (IOP), optic disc cupping and visual field changes and group C of 30 patients of POAG under medical treatment by topical anti-glaucomatous drugs. Serum ceruloplasmin, superoxide dismutase, malondialdehyde and catalase activity were measured in all groups, statistical analysis of the data was performed. Results: In a comparison to group A of control, serum ceruloplasmin decreased significantly in group B of untreated POAG (20.95 ± 6.01) mg-dl and in group C of POAG under treatment (22.15 ± 6.14) mg-dl (P 0.05). Also, serum superoxide dismutase increased significantly in group B (2.23 ± 0.4) and in group C (2.19 ± 0.38) U-ml (P 0.05). Serum malondialdehyde increased significantly in group B (3.82 ± 0.74) nmol-ml and in group C (3.55 ± 0.73) nmol-ml (P 0.05). Serum catalase decreased significantly in group B (17.97 ± 2.75) U-ml and in group C (18.75 ± 2.33) U-ml in a comparison to the control group A (22.67 ± 3.05) U-ml (P 0.05). Conclusions: Serum ceruloplasmin level and the antioxidant (CAT) activity significantly decreased, while serum levels of SOD, MDA significantly increased in cases of POAG. This may indicate the need for addition of anti-oxidative stress therapy in combination with the anti-glaucomatous drugs. Monitoring these markers can be considered good indicators for determination of the oxidative stress condition in such cases.

On the Protective Effects of Aplysin on Ethanol-induced Oxidative Damage in Rat Primary Hepatocytes

[Objective] To investigate the protective effects of Aplysin on ethanol-induced oxidative damage in rat primary hepatocytes.[Methods]Rat primary hepatocytes were obtained via the portal vein collagenase IV in situ perfusion technique followed by a Percoll density gradient centrifuge; MTT test was used to determine the optimum dose of Aplysin and ethanol,and detect the cell vitality in primary hepatocytes; supernatants of primary hepatocytes were harvested to measure AST and LDH level,and the SOD,GSH-PX activities and MDA content in primary hepatocytes were observed; flow cytometry was used to detect the cell apoptosis rate; DNA damage in primary hepatocytes were detected by single-cell gel electrophoresis assay; The level of mitochondrial membrane potential in primary hepatocytes was tested by fluorogenic probe JC-1; the CYP2E1 activity in primary hepatocytes were detected by colorimetry; the proteins of CYP2E1 were detected by Western blotting. [Results]300 mmol/L dose of ethanol and 30 mg/L dose of Aplysin were the optimal dosages and were used in the subsequent experiments. Hepatocyte vitality was significantly increased in the Aplysin group relative to that in the ethanol group,and Aplysin inhibited the release of AST and LDH( P < 0. 05). For the Aplysin treatment group,the activities of hepatocyte SOD and GSH were significantly increased and MDA was markedly lowered as compared with those in the ethanol group( P < 0. 05). And Aplysin can alleviate hepatocyte apoptosis significantly,and hepatocyte DNA damage rate of II-III level and IV level were significantly lowered in the Aplysin treatment group as compared with those in the ethanol group,and Aplysin has evidently improved on alcohol induced mitochondria damage of hepatocyte. Primary hepatocytes activities and protein expression of CYP2E1 were markedly lowered in the Aplysin treatment group as compared with those in the ethanol group( P < 0. 05). [Conclusion] Aplysin has protective effects on liver oxidative damage induced by alcohol of primary cultured rat hepatocytes by blocking CYP2E1 activation,relieving oxidative stress,and sharpening the oxidation resistance ability.

Effect of radiofrequency ablation combined with transcatheter arterial chemoembolization on inflammatory factors, oxidative stress response factors and tumor activity factors in patients with primary liver cancer

Objective:To investigate the effects of radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) on inflammatory factors, oxidative stress response factors and tumor activity factors in primary hepatocellular carcinoma (HCC) patients.Methods:A total of 100 cases of primary liver cancer patients from January 2014 to June 2016 were selected and randomly divided into observation group and control group with 50 cases in each group, the observation group was treated with RFA combined with TACE treatment, the control group was given TACE treatment, compared two groups before treatment (T0), 1 weeks of treatment (T1), 2 weeks (T2) inflammation factor, oxidative stress factor and tumor activity index.Results:(1) The hs-CRP, IL-6 and TNF-α levels of T1 in two groups were significantly increased, T2 decreased significantly, T1>T1>T2, but the observation group hs-CRP, IL-6, TNF-α levels of T1 were higher than the control group and the difference was statistically significant, hs-CRP, IL-6, TNF-α levels of T2 had no statistically significant;(2) The ROS level of T1 in the observation group was higher than the control group, while the SOD and T-AOC levels were lower than the control group, the ROS level of T2 in the observation group was lower than the control group, SOD and T-AOC were higher than the control group, there was significant difference. (3) Serum AFP, CA199 and MMP levels in T1 and T2 of the observation group were lower than the control group, the difference was statistically significant.Conclusion:RFA treatment of HCC may lead to inflammation and increased oxidative stress in the early stage . However, TACE combined with TACE can improve the micro inflammatory state, especially enhance the antioxidant function and decrease the level of tumor active factor.

精准肝蒂解剖技术辅助腹腔镜肝癌切除术的效果及对炎症免疫应激、肝功能的影响

目的探讨精准肝蒂解剖技术辅助腹腔镜肝癌切除术的效果及对炎症免疫应激、肝功能的影响。方法选取达州市中心医院2019年10月至2022年6月114例原发性肝癌患者,按照随机数字表法分为常规组(n=57)与精准组(n=57)。2组均行腹腔镜肝癌切除术,常规组采用常规方法切除肝脏,精准组采用精准肝蒂解剖技术切除肝脏。比较2组手术指标、手术前后炎症-免疫指标[白介素-6(IL-6)、C反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)、免疫球蛋白A(IgA)、IgM、IgG]、肝功能[丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、γ谷氨酰转肽酶(γ-GT)、总胆红素(TBIL)]、肿瘤因子[甲胎蛋白(AFP)、糖类抗原19-9(CA19-9)、胸苷激酶1(TK1)]水平、并发症发生率,并随访1 a,统计2组1 a复发率、生存率。结果2组手术时间、切缘阳性率差异无统计学意义(P>0.05);精准组术中出血量、术后引流量少于常规组,术后拔管时间、住院时间短于常规组(P<0.05);2组术后1 d、3 d、7 d血清IL-6、CRP、TNF-α、ALT、AST、γ-GT、TBIL水平呈升高后降低趋势,且精准组低于常规组(P<0.05),血清IgA、IgM、IgG水平呈降低后升高趋势,且精准组高于常规组(P<0.05);2组术后3个月血清AFP、CA19-9、TK1水平低于术前,精准组低于常规组(P<0.05);精准组并发症发生率5.26%(3/57)低于常规组17.54%(10/57)(P<0.05);随访1 a,精准组失访2例,常规组失访1例,精准组1 a复发率25.45%(14/55)低于常规组44.64%(25/56),1a生存率85.45%(47/55)高于常规组62.50%(35/56)(P<0.05)。结论精准肝蒂解剖技术应用于原发性肝癌腹腔镜肝切除术中能优化手术情况,减轻炎症免疫应激与肝功能损伤,减少并发症,还可明显抑制肿瘤因子表达,降低复发率,提高生存率。

信阳市小学4~6年级儿童心理健康状况与校园欺凌、学业压力的关系

目的:研究信阳市小学4~6年级儿童心理健康状况与校园欺凌、学业压力的关系,为改善儿童心理健康状况提供实证依据。方法:从信阳市抽取6所小学4~6年级儿童1736名为调查对象,采用儿童少年心理健康问卷(Mental Health Scale for Child and Adolescent,MHS-CA)、特拉华欺凌受害量表(学生版)(Delaware Bullying Victimization Scale-Student,DBVS-S)、小学生学习压力问卷进行调查,采用回归分析考察变量之间的关系。结果:①单因素分析显示,男生的MHS-CA评分、学业压力评分高于女生,DBVS-S评分低于女生(P<0.01);城区学生的MHS-CA评分、学业压力评分高于农村,DBVS-S评分低于农村(P<0.001);独生子女的MHS-CA评分、学业压力评分高于非独生子女(P<0.001);汉族学生的学业压力评分高于少数民族,DBVS-S评分低于少数民族(P<0.001);贫困家庭学生的DBVS-S评分高于非贫困家庭,学业压力评分、MHS-CA评分低于非贫困家庭(P<0.001);双亲家庭学生的MHS-CA评分高于单亲或其他家庭,DBVS-S评分低于单亲或其他家庭(P<0.001);留守学生的DBVS-S评分高于非留守学生,MHS-CA评分低于非留守学生(P<0.001);不同年级学生的MHS-CA评分、DBVS-S评分、学业压力评分比较,差异有统计学意义(P<0.001)。②Pearson相关分析法显示,小学生心理健康与校园欺凌、学业压力呈负相关(P<0.05)。③多重线性回归分析发现,影响小学生心理健康状况的因素有家庭经济状况、家庭类型、校园欺凌、学业压力、是否为独生子女、有无留守经历(P<0.05)。结论:生源地为农村、单亲或其他家庭、家庭贫困、非独生子女、有留守经历的4~6年级儿童心理健康状况较差,且与校园欺凌、学业压力有关。

Nrf2/Keap1通路和PINK/Parkin介导的线粒体自噬失调在子痫前期进展中的分子机制研究

目的探讨Nrf2/Keap1通路和PINK/Parkin介导的线粒体自噬失调在子痫前期疾病进展中的分子机制。方法选取2020年6月至2023年1月于海南省人民医院妇产科做孕期检查并分娩的15例有重度子痫前期(sPE)早产史的孕妇的子宫内膜样本作为研究对象,纳入sPE组;并选取同期同院做孕期检查并分娩的15例有正常孕产史的孕妇的子宫内膜样本作为对照,纳入nPCB组。分离两组原代子宫内膜基质细胞(hESCs)。采用流式细胞术(FCM)测定活性氧(ROS)水平,采用酶联免疫吸附试验(ELISA)法测定总超氧化物歧化酶(SOD)、谷胱甘肽(GSH)和谷胱甘肽过氧化物酶(GPx)水平。将hESCs进行处理并分组为nPCB-hESCs组、nPCB-hESCs处理组、sPE-hESCs组、sPE-hESCs处理组。分别对处理组两种来源的hESCs给予cAMP+MPA诱导蜕膜化。采用Western blot测定自噬相关蛋白和线粒体自噬相关蛋白的表达水平,测定JAr细胞球状体向hESCs的植入率。另选取hESCs进行处理并分组为nPCB-hESCs组、nPCB-hESCs+H/R组、sPE-hESCs组、sPE-hESCs+H/R组。H/R组分别对两种来源的hESCs给予缺氧/复氧(H/R)处理。采用实时荧光定量聚合酶链反应(qPCR)和Western blot测定Nrf2/Keap1 mRNA和蛋白质的表达水平。结果与nPCB-hESCs相比,sPE-hESCs中ROS的水平显著升高,SOD、GSH和GPx的水平显著降低(P<0.05)。与nPCB-hESCs组相比,nPCB-hESCs处理组细胞自噬/线粒体自噬相关蛋白表达水平显著升高(P<0.05)。与nPCB-hESCs组相比,sPE-hESCs组JAr细胞向hESCs植入的植入率显著较低(P<0.05)。与nPCB-hESCs处理组相比,sPE-hESCs处理组JAr细胞向hESCs植入的植入率显著较低(P<0.05)。与nPCB-hESCs+H/R组相比,sPE-hESCs+H/R组细胞内Nrf2 mRNA和蛋白质的表达水平显著降低,Keap1 mRNA和蛋白质的表达水平显著升高(P<0.05)。结论有子痫前期史的孕妇hESCs中Nrf2/Keap1通路激活受损和线粒体自噬功能被抑制,导致细胞内ROS的异常积累及其体外蜕膜化功能受损。

丁二磺酸腺苷蛋氨酸联合熊去氧胆酸治疗原发性胆汁性胆管炎的效果及对氧化应激指标的影响

目的研究丁二磺酸腺苷蛋氨酸联合熊去氧胆酸治疗原发性胆汁性胆管炎(PBC)的效果及对氧化应激指标的影响。方法选取2017年5月至2022年5月在我院接受治疗的100例PBC患者为研究对象,根据随机数字表法将其分为对照组和观察组,每组50例。对照组采用熊去氧胆酸治疗,观察组采用丁二磺酸腺苷蛋氨酸联合熊去氧胆酸治疗。比较两组的肝功能指标、炎症和氧化应激指标、临床疗效及不良反应发生情况。结果治疗后,观察组的总胆红素(TBiL)、总胆汁酸(TBA)、丙氨酸氨基转移酶(ALT)、碱性磷酸酶(ALP)以及天冬氨酸氨基转移酶(AST)水平明显低于对照组,差异具有统计学意义(P<0.05)。治疗后,观察组的白细胞介素-12(IL-12)、磷脂转运蛋白(PLTP)、丙二醛(MDA)水平低于对照组,差异具有统计学意义(P<0.05)。观察组的治疗总有效率高于对照组,差异具有统计学意义(P<0.05)。两组的不良反应总发生率比较,差异无统计学意义(P>0.05)。结论丁二磺酸腺苷蛋氨酸联合熊去氧胆酸治疗PBC的效果理想,可明显改善肝功能,抑制机体氧化应激反应。

基于SEPIC的新型高增益DC-DC变换器及衍生拓扑分析

针对光伏并网系统中单开关升压变换器(如SEPIC、Boost、准Z源、二次型)电压增益低和半导体器件电压应力大的问题,提出1种基于SEPIC的外部升压型高增益DC-DC变换器。首先对所提变换器在电感电流连续导通模式和断续导通模式下的工作原理和稳态特性进行详细分析,并与其他新型拓扑进行性能对比。在此基础上,给出了基于外部升压网络的衍生拓扑。最后,通过搭建1台400 V/200 W的实验样机证明了理论分析的准确性。所提变换器利用阻抗网络和开关电容单元构成的外部升压网络提升了SEPIC变换器的电压增益,并改善了半导体器件电压应力大的缺点。

终末期原发性肝癌患者家属心理应激状况及影响因素分析

目的调查终末期原发性肝癌患者家属心理应激状况,探究影响因素。方法本研究为前瞻性研究,选取2021年4月至2023年3月104例终末期原发性肝癌患者的主要照顾者为研究对象,采用家属应激量表(RSS)调查主要照顾者心理应激状况,设计主要照顾者基线资料填写表并记录研究所需资料,分析终末期原发性肝癌患者家属心理应激状况的影响因素。结果共发放104份调查问卷,回收有效问卷104份,有效回收率为100%。104例终末期原发性肝癌患者主要照顾者RSS评分为(21.52±1.84)分,总体处于中高水平。主要照顾者要照顾其他家人、家庭年收入<10万、社会支持度低、病耻感强的主要照顾人的RSS评分高于主要照顾者无需照顾其他家人、家庭年收入≥10万、社会支持度中等/高、病耻感中等/弱者,差异有统计学意义(P<0.05);其他不同资料特征的患者RSS评分比较,差异无统计学意义(P>0.05)。多元线性回归分析显示,主要照顾者要照顾其他家人、家庭年收入低、社会支持度低、病耻感强均为终末期原发性肝癌患者家属心理应激强的影响因素(P<0.05)。结论终末期原发性肝癌患者家属心理应激普遍呈中高水平,可能受家属要照顾其他家人、家庭年收入、社会支持度、病耻感等因素影响。

Cav3.2 channel regulates cerebral ischemia/reperfusion injury:a promising target for intervention

Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.

依折麦布辅助治疗原发性高脂血症合并颈动脉粥样硬化的疗效

目的:探究依折麦布辅助治疗原发性高脂血症合并颈动脉粥样硬化患者的疗效。方法:根据治疗方式不同将120例合并颈动脉粥样硬化的原发性高脂血症患者分为观察组(n=62)和对照组(n=58)。观察组接受依折麦布联合瑞舒伐他汀治疗;对照组接受单独的瑞舒伐他汀治疗,治疗周期均为6个月。对比两组血脂指标[血清低密度脂蛋白(LDL)、氧化低密度脂蛋白(ox-LDL)]、氧化应激指标[同型半胱氨酸(Hcy)、尿酸(UA)、C-反应蛋白(CRP)和总胆红素(TBIL)]浓度变化,并比较颈动脉粥样硬化斑块指标[颈动脉内中膜厚度(C-IMT)、粥样斑块积分]及不良反应发生情况。结果:治疗后,观察组LDL、ox-LDL血清水平、颈动脉内中膜厚度(C-IMT)、粥样斑块积分、血清Hcy均低于对照组(P<0.05);UA和TBIL水平均高于对照组(P<0.05),两组CRP水平无统计学差异(P>0.05)。观察组、对照组均未发生严重不良反应,且两组不良反应总发生率无统计学差异(4.86%vs.1.72%,P>0.05)。结论:依折麦布联合瑞舒伐他汀治疗原发性高脂血症合并颈动脉粥样硬化能有效降低LDL和ox-LDL水平,减少斑块形成,对氧化应激具有明显的抑制作用,且安全性较高。

北京市中小学教师职业紧张现状及其影响因素分析

目的 了解北京市中小学教师职业紧张现状,探讨其影响因素,为缓解中小学教师职业紧张、保护和促进其身心健康提供依据。方法 使用多阶段、PPS抽样法和分层整群随机抽样的方式,选取北京市8个辖区29所学校的中小学教师作为研究对象。结果 本次共调查北京市中小学教师2 143人,职业紧张者占16.66%,其中轻度职业紧张者10.27%(220/2 143)、中度职业紧张者3.87%(83/2 143)、重度职业紧张者2.52%(54/2 143)。职业紧张得分为(41.74±8.30)分,其中不同维度得分为社会支持均分(20.14±3.73)分,组织与回报均分(11.81±3.87)分,要求与付出均分(13.45±3.56)分,自主性均分(5.38±1.73)分。多因素logistic回归分析结果显示,不同月均收入和周工作时间的中小学教师职业紧张检出率差异有统计学意义(P均<0.05)。与税后月均收入≥11 000元相比,税后月均收入<9 000元(OR=1.588,95%CI:1.144~2.205)、税后月均收入9 000~<11 000(OR=1.562,95%CI:1.138~2.144)是中小学教师检出职业紧张的危险因素(P均<0.05);与周工作时间≤40 h比较,周工作时间49~<55 h(OR=2.552,95%CI:1.671~3.898)、周工作时间≥55 h(OR=3.502,95%CI:2.341~5.241)是中小学教师检出职业紧张的危险因素(P均<0.05)。结论 北京市中小学教师存在不同程度的职业紧张问题且主要是轻度职业紧张,月均收入水平、周工作时间超过48 h是北京市中小学教师职业紧张的主要危险因素。

初级纤毛/鞭毛转运系统介导力学反应性信号通路促骨髓基质干细胞成骨分化

背景:目前已证实力学刺激可以促进骨髓基质干细胞成骨分化,但其机制未完全明了。初级纤毛是重要的力学感受器并调控TGF-β1/BMP-2/SMAD等多种信号通路,很可能是骨髓基质干细胞力学调控的重要靶点。目的:探讨流体剪切力对骨髓基质干细胞成骨分化的影响及机制。方法:将大鼠骨髓基质干细胞分为对照组、力学刺激组(通过摇床施加流体剪切力学干预)、力学刺激+IFT88沉默组(力学刺激+使用siRNA沉默IFT88表达),干预24 h后,采用qRT-PCR检测转化生长因子β1、骨形成蛋白2的表达、Western blot检测磷酸化SMAD2/3蛋白的表达,初级纤毛免疫荧光染色及形态学分析。结果与结论:剪切力刺激可促进骨髓基质干细胞的初级纤毛表达,转化生长因子β1及骨形成蛋白2基因转录激活,提高磷酸化SMAD2/3蛋白表达。siRNA干扰初级纤毛生成后,这一力学反应效应明显减低。骨髓基质干细胞的初级纤毛面积改变比值与转化生长因子β1及骨形成蛋白2基因转录增高比例具有Spearman相关性。结果表明:初级纤毛/鞭毛转运系统介导了流体剪切力反应性的TGF-β1/BMP-2/SMAD信号通路激活,促进骨髓基质干细胞成骨分化。

正念减压疗法对永久性肠造口患者主要照顾者照顾负担的效果

目的探讨正念减压疗法对永久性肠造口患者主要照顾者心理韧性、照顾负担的影响。方法采用便利抽样法,选取2021年3月至2022年12月于上海市某三级甲等医院行永久性肠造口术患者的主要照顾者380名为研究对象,随机分为对照组及观察组,每组各190例。对照组给予常规护理干预,观察组在此基础上实施为期4周的正念减压疗法干预。采用心理韧性量表和Zarit照顾负担量表比较两组患者干预前后的心理弹性和照顾负担水平。结果干预4周后,观察组心理韧性各维度得分均高于对照组,差异有统计学意义(P<0.05);观察组照顾者照顾负担各维度得分均低于对照组,差异有统计学意义(P<0.05)。结论正念减压疗法可以有效提高永久性肠造口患者主要照顾者的心理韧性水平,调节其不健康的心理倾向,降低照顾负担。

Influence of pore structure on thermal stress distribution inside coal particles during primary fragmentation

Thermal stress is an important reason of coal particle primary fragmentation,during which the role of pore structure is ambiguous.Thermal stress induced fragmentation experiments were conducted with low volatile coal/char particles,and the results show that the fragmentation severity enhances with increasing porosity.Various porous thermal stress models were developed with finite element method,and the influences of the pore shape,size,position and porosity on the thermal stress were discussed.The maximum thermal stress inside particle increases with pore curvature,the pore position affects the thermal stress more significantly at the particle center and surface.The expectation of the maximum tensile thermal stress linearly increases with porosity,making the particles with higher porosity easier to fragment,contrary to the conclusion deduced from the devolatilization theory.The obtained results are valuable for the analysis of different thermal processes concerning the thermal stresses of the solid feedstocks.

法国核电应力腐蚀问题对我国核电技术发展的启示

2022年,法国电力公司(EDF)大量核电机组因一回路管道应力腐蚀开裂(SCC)问题而停堆检修,对法国甚至欧洲的生产生活造成巨大影响。针对该事件,在总结国内外核反应堆类似失效案例及材料老化研究成果的基础上,对反应堆不锈钢部件的SCC问题的机理、影响因素、抑制措施开展了分析,并结合我国核电机组服役时间逐渐延长,材料老化、设备失效问题日益突出的现状,提出我国核电运维改进措施,如优化残余应力、加强监督和检查,研发更有效的无损检测技术等。同时,探讨了我国在反应堆材料老化研究方面的发展方向。

犬尿氨酸/犬尿酸通路在原发性胆汁性胆管炎伴疲劳小鼠肌肉中的作用及机制研究

目的探究犬尿氨酸(kynurenine,KYN)/犬尿酸(kynuric acid,KYNA)通路在原发性胆汁性胆管炎伴疲劳小鼠肌肉中的作用及机制。方法随机将12只小鼠分成对照组、DDC组、DDC+抑郁组、DDC+抑郁+氯米帕明组,每组3只,对照组常规饲料喂养,DDC+抑郁组和DDC+抑郁+氯米帕明组采用慢性不可预见性温和应激方法复制小鼠抑郁模型;2周后DDC组、DDC+抑郁组、DDC+抑郁+氯米帕明组同时开始连续喂养含有0.1%的DDC饲料建立胆汁淤积模型,同时DDC+抑郁+氯米帕明组腹腔注射盐酸氯米帕明(7.5 mg·kg^(-1)·d^(-1))连续14 d,其余组小鼠经腹腔注射生理盐水。观察并记录小鼠体质量变化。进行负重游泳实验,记录各组小鼠的负重游泳时间。采用强迫游泳实验和悬尾实验评价小鼠抑郁效果。应用ELISA检测各组小鼠血清和肌肉中KYN、KYNA含量的变化;取肝脏和肌肉进行HE染色,观察肝脏和肌肉组织病理学变化;采用ROS染色分析肌肉氧化损伤的程度。结果与对照组相比,DDC组、DDC+抑郁组和DDC+抑郁+氯米帕明组小鼠表现出明显的疲劳和抑郁样行为(P<0.05);对比DDC组,DDC+抑郁组的疲劳和抑郁样行为加重(P<0.05);DDC+抑郁+氯米帕明组的疲劳和抑郁较DDC+抑郁组减轻(P<0.05)。小鼠肝组织和肌组织HE染色结果显示,相比对照组,DDC组、DDC+抑郁组和DDC+抑郁+氯米帕明组表现出不同程度病理损伤;DDC+抑郁+氯米帕明组小鼠的肝和肌组织病理损伤较DDC+抑郁组减轻。与对照组相比,DDC组、DDC+抑郁组和DDC+抑郁+氯米帕明组小鼠肌肉中ROS含量表现出不同程度升高;与DDC+抑郁组相比,DDC+抑郁+氯米帕明组小鼠肌肉中ROS含量显著下降。相比对照组,DDC组、DDC+抑郁组和DDC+抑郁+氯米帕明组小鼠血清和肌肉中KYN水平显著升高(P<0.05),KYNA水平显著下降(P<0.05);DDC+抑郁组小鼠血清和肌肉中KYN浓度比DDC组明显升高(P<0.05);DDC+抑郁+氯米帕明组小鼠血清和肌肉中KYN浓度比DDC+抑郁组明显降低(P<0.05)。结论KYN/KYNA通路在原发性胆汁性胆管炎伴疲劳小鼠中对外周疲劳有调控作用,抗抑郁治疗能改善肌肉疲劳。