Shizhenqing granule stimulates the hypothalamic-pituitary-adrenal axis and reduces serum pro-inflammatory factors in a rat model with chronic eczema

Objective:In this study,we examined the effects of Shizhenqing granule(SZQG)on hypothalamicpituitary-adrenal(HPA)axis and serum inflammatory factors in a rat model of chronic eczema,in order to explore the mechanism of action of SZQG in treatment of this disease.Methods:Sixty SpragueeDawley male rats were randomly divided into six groups(with 10 rats per group):blank group;model group;positive control group(prednisone);and the low-,medium-,and high-dose SZQG groups.Except for the blank group,rats in all other groups were treated with 2,4-dinitrochlorobenzene to induce chronic eczema.These rats were administered prednisone or SZQG for 7 consecutive days after successful establishment of the chronic eczema model,and samples were collected 12 h after the last administration.The degree of skin lesions and the changes in serum levels of corticotropin-releasing hormone(CRH),adrenocorticotropic hormone(ACTH),cortisol(CORT),interleukin(IL)-4,interferon(IFN)-g,IL-25,and IL-31 among the groups were compared.Results:SZQG effectively increased the levels of CRH,ACTH,and CORT,which decreased in the serum of rats with chronic eczema,stimulated the function of the HPA axis,and promoted the expression of glucocorticoids.SZQG reduced the serum levels of inflammatory factors including IL-4,IL-25 and IL-31,which were overexpressed in rats with chronic eczema,and increased those of anti-inflammatory factor IFN-g,thereby alleviating the inflammatory symptoms and itching,and ameliorating the clinical symptoms of chronic eczema.Conclusion:SZQG effectively alleviates skin lesions in the chronic eczema rat model by stimulating the function of the HPA axis.

The total flavonoids extracted from Xiaobuxin Tang reverse the hyperactivity of hypothalamic-pituitary-adrenal axis in chronically stressed rats

Objective To investigate the effect of XBXT-2 on the activity of hypothalamic-pituitary-adrenal(HPA)axis in chronic mild stress(CMS)model of rats.Methods Using ELISA to test the serum corticosterone,adrenocorticotropic hormone(ACTH)and corticotropin-releasing hormone(CRH)level in CMS rats;Using western blot to determine hippocampal glucocorticoids receptors(GR)expression in CMS rats.Results Co-administration of XBXT-2(25,50 mg·kg-1,p.o.,28 days,the effective doses for behavioral responses)significantly decreased the serum corticosterone and ACTH level in CMS rats,while the CRH level was not markedly affected by chronic stress or drugs.Moreover,XBXT-2 significantly increased the GR expression in the hippocampus of CMS rats.The same effects were observed in the positive control drug imipramine(10 mg·kg-1,p.o.).Conclusions The decrease of serum corticosterone and ACTH level,as well as the increase of hippocampal GR expression may be the mechanisms underlying the antidepressant action of XBXT-2,which may associate with HPA axis.

Seasonal photoperiodic influence of pineal melatonin on hypothalamic-pituitary-adrenal axis-hippocampal-receptor in male rats

Background: Based on the effect of seasonal changes on human visceral function, this study investigated the impact of seasonal photoperiod of the pineal body on hypothalamic-pituitary-adrenal axis-hippocampal-receptor in rats, aiming to reveal the mechanism by which pineal gland melatonin regulates the seasonal secretion of hippocampal neurotransmitters.Methods: Vernal equinox, summer solstice, autumn equinox, and winter solstice were selected as four experimental time points, and rats were randomly divided into normal control group, sham operation group, and pinealectomized group. The seasonal changes in corticotropin-releasing hormone(CRH),adrenocorticotropic hormone(ACTH), corticosterone, hypothalamic melatonin receptor(MTR), and hippocampal corticosterone receptor(CORTR) were examined by enzyme-linked immunosorbent assay.Results: Comparing the same group between different seasons, we showed that in the normal control group, CRH, ACTH, corticosterone, and MTR were higher, while CORTR was lower in autumn and winter than in spring(all P <.05). Compared with the normal control group, the pinealectomized group showed higher levels of corticosterone(P =.01), MTR(P =.01), and CORTR(P =.03) during spring;reduced levels of MTR and CORTR(both P <.001) during summer;higher levels of ACTH(P =.001) and MTR(P <.001),and lower levels of CRH(P =.001), corticosterone(P <.001), and CORTR(P =.003) during autumn;and lower levels of CRH(P <.001) and MTR(P =.004), and higher level of ACTH(P <.001) in winter.Conclusions: Seasonal photoperiod acts on the pineal gland to secrete different levels of melatonin,resulting in seasonal changes in the hypothalamic-pituitary-adrenal axis-hippocampal-receptor, which may be the pathophysiological basis for the onset of seasonal affective disorder.

Individual Differences in Stress Responsiveness of the Hypothalamic-Pituitary-Adrenal Axis and Its Vasopressinergic Regulation in Old Monkeys

Stress adaptation is fundamental for health, and the hypothalamic-pituitary-adrenal axis (HPA) is one of its main mechanisms. Considerable data indicate that arginine vasopressin (AVP) related disturbances of stress adaptation can occur with aging. However, most studies of such kind have been performed on rodents, give contradictory results and fail to consider individual characteristics of the animals. The purpose of this study was to investigate individual HPA responsiveness to acute stress and its vasopressinergic regulation in old female rhesus monkeys that differ in their behavioral responses to stress. Animals with depression-like or anxiety-like behavior (DAB) responded with higher plasma levels of ACTH and AVP, lower levels of corticosteroids and higher cortisol/DHEAS molar ratios to restraint stress and to insulin-induced hypoglycemia compared with animals with healthy adaptive behavior. AVP and ACTH dynamics were closely correlated in most animals. AVP treatment produced differences in HPA responses similar to those produced by the stressors. The ACTH response to hypoglycemic stress in the DAB animal with highest HPA responsiveness was dramatically reduced by prior administration of a V1b receptor antagonist. These results suggest that the dysfunctions of HPA observed in old animals with DAB are caused by increased tone of the vasopressinergic system in regulation of HPA stress reactivity.

Functional gastrointestinal disorders and gut-brain axis: What does the future hold?

Despite their high prevalence, lack of understanding of the exact pathophysiology of the functional gastrointestinal disorders has restricted us to symptomatic diagnostic tools and therapies. Complex mechanisms underlying the disturbances in the bidirectional communication between the gastrointestinal tract and the brain have a vital role in the pathogenesis and are key to our understanding of the disease phenomenon. Although we have come a long way in our understanding of these complex disorders with the help of studies on animals especially rodents, there need to be more studies in humans, especially to identify the therapeutic targets. This review study looks at the anatomical features of the gut-brain axis in order to discuss the different factors and underlying molecular mechanisms that may have a role in the pathogenesis of functional gastrointestinal disorders. These molecules and their receptors can be targeted in future for further studies and possible therapeutic interventions. The article also discusses the potential role of artificial intelligence and machine learning and its possible role in our understanding of these scientifically challenging disorders.

A Semi-analytical Method for Vibrational and Buckling Analysis of Functionally Graded Nanobeams Considering the Physical Neutral Axis Position

In this paper,a semi-analytical method is presented for free vibration and buckling analysis of functionally graded(FG)size-dependent nanobeams based on the physical neutral axis position.It is the first time that a semi-analytical differential transform method(DTM)solution is developed for the FG nanobeams vibration and buckling analysis.Material properties of FG nanobeam are supposed to vary continuously along the thickness according to the power-law form.The physical neutral axis position for mentioned FG nanobeams is determined.The small scale effect is taken into consideration based on nonlocal elasticity theory of Eringen.The nonlocal equations of motion are derived through Hamilton’s principle and they are solved applying DTM.It is demonstrated that the DTM has high precision and computational efficiency in the vibration analysis of FG nanobeams.The good agreement between the results of this article and those available in literature validated the presented approach.The detailed mathematical derivations are presented and numerical investigations are performed while the emphasis is placed on investigating the effect of the several parameters such as neutral axis position,small scale effects,the material distribution profile,mode number,thickness ratio and boundary conditions on the normalized natural frequencies and dimensionless buckling load of the FG nanobeams in detail.It is explicitly shown that the vibration and buckling behaviour of a FG nanobeams is significantly influenced by these effects.

Tilted Axis Rotation of ^(57)Mn in Covariant Density Functional Theory

The self-consistent tilted axis cranking covariant density functional theory based on the point-coupling interaction is applied to investigate the tilted axis rotation in ^57 Mn. The observed data for band C are reproduced well with the assigned configuration eonfig 1. The shears mechanism for magnetic rotation is examined by investigating microscopically the orientation of angular momentum and the corresponding contributions. It is found that config 1 and config 3 correspond to a rotation of high-K character. Config 2 corresponds to a rotation of magnetic character. However, due to the presence of electromagnetic transition B（M1） and B（E2）, collective rotation plays an essential role in the competition with magnetic rotation.

Functional changes in the hypothalamic-pituitary-adrenal axis after successful cardiopulmonary resuscitation

Background:Cardiac arrest(CA)is a terminal event that results in a range of pathophysiological changes in the body,most notably,systemic ischemia-reperfusion injury.The hypothalamic-pituitary-adrenal(HPA)axis is an important neuroendocrine system that modulates adrenocortical hormone release.This study was designed to investigate the changes in HPA-related hormone levels after successful cardiopulmonary resuscitation(CPR)and to explore possible etiologies to provide a basis for relevant clinical research.Methods:We collected the clinical data of 96 patients with CA admitted to the Emergency Department of Beijing Chaoyang Hospital,Capital Medical University,between January 2016 and May 2017.Serum samples were collected 6,24,and 72 hours after restoring spontaneous circulation(ROSC).The data were compared with those of the healthy control group(n=50).An enzyme-linked immunosorbent assay(ELISA)was performed to measure copeptin,adrenocorticotropic hormone(ACTH),corticotropin-releasing hormone(CRH),and total cortisol.Demographic data were collected for both groups.For the CPR group,clinical data and the end-of-study cerebral performance category(CPC)were analyzed.Patients were followed up through day 28.Death or survival after day 28 was used as the study endpoint.Simple values were expressed as medians and quartiles or ratios(%)for statistical analysis.Continuous variables are expressed as mean±standard deviation.Categorical variables were expressed as frequencies and percentages.The mean values of normally distributed measurement data were analyzed using 1-way analysis of variance(ANOVA)for among-group comparisons and the least significant difference(LSD)test for between-group comparisons.SPSS v17(SPSS,Chicago,IL,USA)was used for statistical analysis,and P<0.05 was considered statistically significant.Results:No significant between-group differences were observed in terms of age or sex.The 28-day mortality rate in the CPR group was 71%.ACTH and CRH levels were significantly lower in the CPR group than in the healthy control group(P<0.001).Copeptin and cortisol levels 6 hours after ROSC were significantly higher in the CPR group than in the healthy control group(P<0.001).No significant changes in any indicator were observed over time(6,24,and 72 hours after ROSC)(P>0.05).The CPC score was 1–2(good cerebral performance group)in 13 patients,3–4(poor cerebral performance group)in 17 patients,and 5(brain death or clinical death)in 66 patients.Patients with significantly declining ACTH and CRH levels had higher CPC scores(P<0.05);however,no significant differences were found in other indicators(P>0.05).Conclusion:After post-CA ROSC,ischemia-reperfusion injury may cause brain damage and HPA axis damage and dysfunction,the severity of which is associated with CPC score.

Neuroimaging the brain-gut axis in patients with irritable bowel syndrome

AIM:To summarize and synthesize current literature on neuroimaging the brain-gut axis in patients with irritable bowel syndrome(IBS).METHODS:A database search for relevant literature was conducted using Pub Med,Scopus and Embase in February 2015.Date filters were applied from the year2009 and onward,and studies were limited to those written in the English language and those performed upon human subjects.The initial search yielded 797articles,out of which 38 were pulled for full text review and 27 were included for study analysis.Investigations were reviewed to determine study design,methodology and results,and data points were placed in tabular format to facilitate analysis of study findings across disparate investigations.RESULTS:Analysis of study data resulted in the abstraction of four key themes:Neurohormonal differences,anatomic measurements of brain structure and connectivity,differences in functional responsiveness of the brain during rectal distention,and confounding/correlating patient factors.Studies in this review noted alterations of glutamate in the left hippocampus(HIPP),commonalities across IBS subjects in terms of brain oscillation patterns,cortical thickness/gray matter volume differences,and neuroanatomical regions withincreased activation in patients with IBS:Anterio cingulate cortex,mid cingulate cortex,amygdala anterior insula,posterior insula and prefrontal cortex.A striking finding among interventions was the substantia influence that patient variables(e.g.,sex,psychologica and disease related factors)had upon the identification of neuroanatomical differences in structure and con nectivity.CONCLUSION:The field of neuroimaging can provide insight into underlying physiological differences that distinguish patients with IBS from a healthy population.

Gut bless you:The microbiota-gut-brain axis in irritable bowel syndrome

Irritable bowel syndrome(IBS)is a common clinical label for medically unexplained gastrointestinal symptoms,recently described as a disturbance of the microbiota-gut-brain axis.Despite decades of research,the pathophysiology of this highly heterogeneous disorder remains elusive.However,a dramatic change in the understanding of the underlying pathophysiological mechanisms surfaced when the importance of gut microbiota protruded the scientific picture.Are we getting any closer to understanding IBS’etiology,or are we drowning in unspecific,conflicting data because we possess limited tools to unravel the cluster of secrets our gut microbiota is concealing?In this comprehensive review we are discussing some of the major important features of IBS and their interaction with gut microbiota,clinical microbiota-altering treatment such as the low FODMAP diet and fecal microbiota transplantation,neuroimaging and methods in microbiota analyses,and current and future challenges with big data analysis in IBS.

Gut-liver axis and probiotics: Their role in non-alcoholic fatty liver disease

The incidence of obesity and its related conditions, including non-alcoholic fatty liver disease(NAFLD), has dramatically increased in all age groups worldwide. Given the health consequences of these conditions, and the subsequent economic burden on healthcare systems, their prevention and treatment have become major priorities. Because standard dietary and lifestyle changes and pathogenically-oriented therapies(e.g., antioxidants, oral hypoglycemic agents, and lipid-lowering agents) often fail due to poor compliance and/or lack of efficacy, novel approaches directed toward other pathomechanisms are needed. Here we present several lines of evidence indicating that, by increasing energy extraction in some dysbiosis conditions or small intestinal bacterial overgrowth,specific gut microbiota and/or a"low bacterial richness"may play a role in obesity,metabolic syndrome,and fatty liver.Under conditions involving a damaged intestinal barrier("leaky gut"),the gut-liver axis may enhance the natural interactions between intestinal bacteria/bacterial products and hepatic receptors(e.g.,toll-like receptors),thus promoting the following cascade of events:oxidative stress,insulinresistance,hepatic inflammation,and fibrosis.We also discuss the possible modulation of gut microbiota by probiotics,as attempted in NAFLD animal model studies and in several pilot pediatric and adult human studies.Globally,this approach appears to be a promising and innovative add-on therapeutic tool for NAFLD in the context of multi-target therapy.

适宜运动与过度训练调控肠道功能和肠-脑轴的作用机制

对运动介导肠道与大脑联络的相关文献进行综述,分析适宜运动与过度训练对肠道功能和肠-脑轴之间神经传导及生物信号分子的影响,以揭示其作用机制。发现:肠道与大脑之间关系密切,肠-脑轴之间的双向神经联系和相关生物信号分子是实现肠道与大脑之间对话的媒介。运动可通过调控肠道与大脑之间的神经联系和相关生物分子影响肠-脑轴,介导肠道与大脑的健康及神经、精神疾病的转归。肠道微生物是实现肠-脑轴之间信息沟通的重要参与者,运动对肠道功能与肠-脑轴的调节可通过调控肠道微生态,及其介导的神经传导途径和生物信号分子的变化发挥终端效应,进而影响高级神经功能。不同强度的运动对肠道微生态及肠-脑轴的调节效应差异颇大,适宜运动和过度训练引起的干预结果截然不同。

基于下丘脑-垂体-肾上腺轴探讨电针对功能性消化不良大鼠的作用机制

目的探讨电针印堂、内关、足三里对FD大鼠下丘脑-垂体-肾上腺轴的可能作用机制。方法40只SD大鼠随机分为空白组、模型组和电针组。采用夹尾、不规律饮食以及冰生理盐水灌胃法复制FD模型。造模后,电针组行针刺干预,每天1次,每次30 min,连续14天。记录大鼠的一般状态;旷场实验检测大鼠的自主行为及紧张度;HE染色法观察大鼠胃黏膜形态及炎症反应;实时荧光定量PCR法检测大鼠下丘脑5-羟色胺3受体(5-HT3R)、促肾上腺皮质激素释放激素(CRH)的表达;蛋白免疫印迹法检测大鼠十二指肠促肾上腺皮质激素释放激素受体2(CRHR2)、NOD样受体蛋白6(NLRP6)蛋白表达;阿利新蓝染色观察大鼠十二指肠黏膜上皮形态及杯状细胞的阳性表达。结果与空白组相比,模型组大鼠一般状态、旷场自主运动距离、运动速度、十二指肠CRHR2、NLRP6蛋白均大幅下降(P<0.05),下丘脑5-HT3R、CRH mRNA明显升高(P<0.05)。与模型组相比,电针组大鼠一般状态、旷场自主运动距离、运动速度、十二指肠CRHR2、NLRP6蛋白及杯状细胞的表达均明显提高(P<0.05),下丘脑5-HT3R、CRH mRNA大幅下降(P<0.05)。模型组大鼠胃黏膜可见疏松的结缔组织,黏膜下层轻度水肿,淋巴细胞增生;空白组和电针组大鼠胃黏膜结缔组织排列紧密,胃腺间质无明显增生,未见炎症细胞。结论电针印堂、内关、足三里可能是通过提升十二指肠CRHR2、NLRP6蛋白和杯状细胞表达,抑制下丘脑5-HT3R、CRH的表达,来提高FD大鼠自主运动水平,缓解焦虑,修复缺损的肠道黏膜屏障,恢复下丘脑-垂体-肾上腺轴的正常功能。

脑组织GDF-15水平与脑梗死大鼠血管新生以及Th1/Th2免疫平衡轴的关系

目的:探讨脑组织GDF-15水平与脑梗死大鼠血管新生以及Th1/Th2免疫平衡轴的关系。方法:45只雄性SD大鼠随机分为脑梗死模型组、假手术组以及正常对照组,15只/组。模型组采用线栓法建立脑梗死模型,假手术组仅暴露颈内动脉后直接缝合皮肤,建模成功后1周评估大鼠改良神经功能缺损(mNSS)评分。采用HE染色检测脑组织病理学变化情况,Western blot法检测大鼠脑组织中组织生长分化因子-15(GDF-15)蛋白水平,RTPCR测定脑组织中GDF-15 mRNA水平。采用ELISA法检测脑组织INF-γ、IL-4表达情况,采用Spearman相关性分析大鼠脑组织中GDF-15蛋白、mRNA表达水平分别与mNSS评分、微血管密度(MVD)、INF-γ/IL-4水平之间的相关性。结果:模型组大鼠mNSS评分明显高于假手术组和正常对照组(P<0.001),模型组脑梗死面积比为(24.45±4.15)%,假手术组和正常对照组未发现脑梗死区域。模型组大鼠脑组织GDF-15蛋白、mRNA、MVD、INF-γ/IL-4水平均明显高于假手术组和正常对照组(P<0.05)。Spearman相关性分析显示,模型组大鼠脑组织中GDF-15蛋白、mRNA表达水平分别与mNSS评分、MVD、INF-γ/IL-4水平呈正相关关系(P<0.001)。结论:脑梗死大鼠脑组织中GDF-15处于高表达状态,且与神经功能密切关联,其作用机制可能与血管新生以及调控Th1/Th2免疫平衡轴有关。

基于“脑-肠轴”理论论治儿童功能性便秘探析

功能性便秘为一种排便困难、排便频次减少或排便不尽感为主要临床表现的功能性肠病,是儿科临床的常见病和多发病之一。功能性便秘会严重影响患儿的生活质量和心理健康,给患儿及家庭带来一定的困扰。近年来随着“脑-肠轴”研究逐渐深入,越来越多的证据表明脑与肠存在密切联系,“脑-肠轴”作为由中枢神经系统、自主神经系统和肠神经系统共同组成的联络大脑与胃肠道的双向交通机制的神经-内分泌网络系统,脑肠肽能够连接并调控“脑-肠轴”交互作用的各个环节,功能性便秘的产生也和“脑-肠轴”密切相关。在中医理论中,便秘病机为大肠传导失调,脑与肠密切相关,脑居于上,统御五脏六腑,肠腑居于下,传化糟粕,影响人体气机,肠腑通畅,则府精神明,脑肠生理相连、病理相关,脑、肠功能失调,共同导致儿童功能性便秘的发生。本文基于“脑-肠轴”理论,结合中医理论及病因病机,探讨“脑-肠轴”对儿童功能性便秘的影响,并探析基于“脑-肠轴”理论论治儿童功能性便秘。

王雪峰教授基于“脑肠相关”理论治疗儿童功能性便秘经验探析

儿童功能性便秘作为儿科常见病之一,主要表现为排便困难、排便频次减少、排便时间延长。本病发病率、复发率较高,严重影响患儿生活质量,不利于儿童的生长发育。近年来随着社会压力的增大,本病发病率又逐年升高,除身体症状外,患儿的精神症状也逐渐受到关注,且功能性便秘患儿伴发情志异常症状多见。罗马Ⅳ中针对功能性便秘提出其发病的机制主要为“脑与肠间互动异常”,结合中医学“五脏一体”的整体观念与形神俱为一体的理论观点,故本文从“脑肠相关”理论和现代医学中的“脑-肠轴”作为切入点,对“脑肠相关”学说进行深入分析,基于脑与肠生理上相互关联、病理上相互影响的特殊联系,认为治疗功能性便秘不仅应调节胃肠功能以改善肠道症状,也应重视心脑的调神作用以改善患者焦虑、抑郁等精神症状,探究从调神以达运肠之效的治疗方法,以期找寻出治疗功能性便秘的新思路,为提高功能性便秘患儿生活质量提供新方法。

基于脑-肠-菌轴探讨天枢穴治疗功能性便秘作用机制

功能性便秘(functional constipation,FC)是常见的一种胃肠功能紊乱疾病,该病发病机制复杂,脑-肠-菌轴(BGMA)在其病理生理中的作用逐渐受到关注,脑-肠与肠道菌群交互障碍可通过神经、内分泌、免疫和代谢等途径影响胃肠道运动、感觉、分泌等功能,进而引起排便异常。天枢穴具有疏调肠腑、理气行滞、健脾和胃、调神的功效,为针灸临床治疗FC的要穴。现代研究表明,针灸天枢穴对该病的影响机制可能与调节BGMA有关,包括促进中枢神经系统、肠神经系统结构与功能的正常化,改善肠道微生态失调,调节脑肠肽的分泌以及抑制促肾上腺皮质激素释放因子的过度表达等。该文从BGMA角度探究脑-肠轴、肠道菌群与FC的发病关系,总结探讨天枢穴治疗FC的内在机制,以期为针灸治疗功能性胃肠疾病提供理论依据和临床应用指导。

五味子苷B调控miR-370-3p/CCL3轴对幼年肺炎小鼠免疫炎症因子水平的影响

目的:探讨五味子苷B(Sch B)在幼年肺炎小鼠的作用机制。方法:将90只幼年雄性小鼠随机分为对照组、模型组、Sch B低剂量组(Sch BL组)、Sch B高剂量组(Sch BH组)、Sch BH+antagomir-NC组、Sch BH+miR-370-3p antagomir组各15只。Sch BL组和Sch BH组小鼠分别灌胃20、60 mg/kg的Sch B;Sch BH+antagomir-NC组和Sch BH+miR-370-3p antagomir组,先将1 nmol的miR-370-3p antagomir、antagomir-NC用20μL的磷酸盐缓冲液(PBS)溶解,在Sch B灌胃后将miR-370-3p antagomir、antagomir-NC质粒分别经尾静脉注射到小鼠体内;对照组和模型组给予等量生理盐水。每天1次,持续给药7 d。测定各组小鼠肺组织的湿干质量比;采用苏木精-伊红(HE)染色观察各组小鼠肺组织的病理形态;检测各组小鼠肺组织中炎症因子水平;流式细胞术检测外周血T淋巴细胞亚群;实时定量反转录聚合酶链式反应(qRT-PCR)检测肺组织中miR-370-3p和CCL3的mRNA水平;双荧光素酶实验验证miR-370-3p与CCL3的靶向关系。结果:与对照组相比,模型组幼鼠肺组织结构紊乱,肺泡壁变厚,出现大量炎性细胞浸润,组织受损严重,肺组织湿干质量比、CD8^(+)、肿瘤坏死因子(TNF)-α、白细胞介素(IL)-6、CCL3 mRNA水平均升高,CD4^(+)、CD4^(+)/CD8^(+)、miR-370-3p水平均降低(P均<0.05)。与模型组相比,Sch BL组和Sch BH组幼鼠肺组织中肺泡壁变薄,炎性细胞浸润明显减少,损伤减轻,肺组织湿干质量比、CD8^(+)、TNF-α、IL-6、CCL3 mRNA水平均降低,CD4^(+)、CD4^(+)/CD8^(+)、miR-370-3p水平均升高(P均<0.05)。加入miR-370-3p antagomir进行回补实验,结果显示Sch B对肺炎幼鼠免疫功能和炎症保护作用被逆转,且CCL3 mRNA水平升高(P<0.05);双荧光素酶报告基因实验验证了miR-370-3p与CCL3存在靶向关系。结论:Sch B能够通过靶向调节miR-370-3p/CCL3轴来增强幼年肺炎小鼠免疫功能,并抑制炎症反应。

心理应激对皮肤屏障功能的不良影响

皮肤是机体和外界环境之间的第一道保护性屏障,在保护机体免受外界环境等危险因素造成的损伤方面起着重要的作用。心理应激是人在面对各种压力和挑战时产生的情绪和心理反应,多种因素都可以作为心理应激的应激源。长期的心理应激会造成机体内环境稳态失衡,甚至疾病发生。迄今为止有众多研究表明心理应激可通过神经内分泌反应,导致皮肤细胞功能减弱或异常,从而深刻影响皮肤局部生理功能,引起皮肤屏障功能的显著变化,导致皮肤健康问题产生。本文主要综述心理应激影响皮肤屏障功能的相关研究进展。

低复杂度永磁同步电机双矢量模型预测控制策略

针对永磁同步电机模型预测电流控制中计算量大和电流波动问题,提出了一种低复杂度双矢量模型预测电压控制策略。该方法无需遍历所有的电压矢量,仅通过代价函数预测和评估三个不相邻的有效电压矢量,根据三个代价函数值的关系,即可精确快速地确定两个相邻最优有效电压矢量。最优有效的电压矢量选择可以减少预测计算量,同时引入dq轴电压差作用时间计算方法,计算最优有效电压矢量作用时间,以降低计算量。仿真结果表明,相较于占空比策略和传统双矢量模型预测电流控制策略,所提控制策略在保证系统稳态和动态性能的基础上,降低了计算复杂度和电流波动,改善了转矩脉动。