Attenuation of endothelium-dependent relaxation in mesenteric artery during noise-induced hypertension

The present study was designed to determine whether there is a causal relationship between noise-induced hypertension and changes of endothelial function. Rats were exposed to noise stress (100 dB, 1 kHz, 4 h/day, 6 days/week) for 1–4 weeks. The systolic blood pressure was significantly increased after rats were exposed to noise stress for 3 weeks. The relaxant responses of isolated mesenteric arterial rings to endothelium-dependent vasodilators (A23187 and acetylcholine) in noise-treated rats were significantly less than those in control rats. This difference in response to acetylcholine still existed in the presence of methylene blue or N-nitro-L-arginine. On the other hand, the responses to the endothelium-independent vasodilator nitroglycerin were not affected in rats exposed to noise stress. The attenuation to endothelium-dependent vasodilators during noise stress may result in increasing peripheral vascular resistance and thus elevate blood pressure. This indicates that noise-induced hypertension may be partly due to the alterations of endothelial activity.     

Gum Chewing Inhibits the Sensory Processing and the Propagation of Stress-Related Information in a Brain Network

Stress is prevalent in human life and threatens both physical and mental health; stress coping is thus of adaptive value for individual''s survival and well-being. Although there has been extensive research on how the neural and physiological systems respond to stressful stimulation, relatively little is known about how the brain dynamically copes with stress evoked by this stimulation. Here we investigated how stress is relieved by a popular coping behavior, namely, gum chewing. In an fMRI study, we used loud noise as an acute stressor and asked participants to rate their feeling of stress in gum-chewing and no-chewing conditions. The participants generally felt more stressful when hearing noise, but less so when they were simultaneously chewing gum. The bilateral superior temporal sulcus (STS) and the left anterior insula (AI) were activated by noise, and their activations showed a positive correlation with the self-reported feeling of stress. Critically, gum chewing significantly reduced the noise-induced activation in these areas. Psychophysiological interaction (PPI) analysis showed that the functional connectivity between the left AI and the dorsal anterior cingulate cortex (dACC) was increased by noise to a lesser extent when the participants were chewing gum than when not chewing gum. Dynamic causality modeling (DCM) demonstrated that gum chewing inhibited the connectivity from the STS to the left AI. These findings demonstrate that gum chewing relieves stress by attenuating the sensory processing of external stressor and by inhibiting the propagation of stress-related information in the brain stress network.     

Reg3b在大鼠耳蜗的分布及噪声刺激后的表达变化

目的：探讨Reg3b在大鼠耳蜗中的分布情况及在噪声刺激前后的表达变化,为治疗噪声性聋提供新思路。方法：30只健康成年SD大鼠,分为噪声暴露组和正常对照组,利用110dBSPL宽频稳态白噪声对噪声组进行噪声暴露,通过免疫组织荧光技术,观察Reg3b在正常及噪声刺激后成年sD大鼠耳蜗内的分布情况。采用实时定量PCR技术（Realtime-PCR）方法检测大鼠接受噪声刺激前后Reg3b在耳蜗内的表达变化。结果：免疫组织荧光技术提示,Reg3b在噪声暴露后主要表达于大鼠耳蜗的内毛细胞、外毛细胞,以及螺旋神经节处,而正常大鼠耳蜗中Reg3b表达不明显或呈阴性表达。与噪声刺激前相比,噪声刺激后,Reg3b在mRNA水平表达较噪声前明显提高。结论：Reg3b在耳蜗内的分布及在噪声刺激后的表达显著升高提示其在噪声诱导的细胞死亡及对抗噪声损伤方面具有一定作用,可能成为治疗感音神经性聋的新靶点。     

Cytophotometric assessment of Feulgen-DNA and coomassie-total cell protein in adrenocortical fasciculata cells of noise-exposed Wistar rats.

The present investigation was undertaken to examine possible noise-induced alterations in adrenal fasciculata cell (AFC) metabolism, and also to determine if the magnitude of these changes differs in male versus female rats. Wistar rats approximately 3 months old were exposed to intense noise for 60 min (100 dB, re 2 x 10(-5) N(m2)-1, 350-20,000 Hz); control rats were housed under identical conditions, at an ambient noise level of 40-60 dB. Adrenal fasciculata cells (AFC) from each animal were examined for noise-induced alterations in Feulgen-DNA reactivity (as an indicator of chromatin template activity) and Coomassie-total cell protein levels using scanning-integrating cytophotometry. The results provide evidence that intense noise elicited a marked AFC metabolic enhancement in both male and female rats; the degree of this enhancement was more pronounced in males. This disparity may be due to pre-existing differences in male versus female AFC enzymatic capability and subsequent responsiveness to noise-induced activation.     

Noise propagation and signaling sensitivity in biological networks: a role for positive feedback

Interactions between genes and proteins are crucial for efficient processing of internal or external signals, but this connectivity also amplifies stochastic fluctuations by propagating noise between components. Linear (unbranched) cascades were shown to exhibit an interplay between the sensitivity to changes in input signals and the ability to buffer noise. We searched for biological circuits that can maintain signaling sensitivity while minimizing noise propagation, focusing on cases where the noise is characterized by rapid fluctuations. Negative feedback can buffer this type of noise, but this buffering comes at the expense of an even greater reduction in signaling sensitivity. By systematically analyzing three-component circuits, we identify positive feedback as a central motif allowing for the buffering of propagated noise while maintaining sensitivity to long-term changes in input signals. We show analytically that noise reduction in the presence of positive feedback results from improved averaging of rapid fluctuations over time, and discuss in detail a particular implementation in the control of nutrient homeostasis in yeast. As the design of biological networks optimizes for multiple constraints, positive feedback can be used to improve sensitivity without a compromise in the ability to buffer propagated noise.     

Nightmares as a Coping Mechanism for Stress

The cause of nightmares remains unclear. However, previous research suggests that stress may play a key role and that nightmares may actually serve a beneficial function. Thus, the purpose of this study was to examine the overall relationship between these two variables and assess the hypothesis that nightmares serve as a coping mechanism for stress. To accomplish these goals, a group of 412 psychology students were separated into low, medium, and high nightmare frequency groups as well as low, medium, and high nightmare intensity groups. Comparisons were then conducted for daily stressors, life stressors, social support, and coping. Most notably, this study demonstrated a positive association between nightmares and coping with stress. The overall pattern seen in the analyses reflect the significant relationship between nightmares and stress, while the finding that nightmares were positively associated with coping bolsters the supposition that nightmares may help to alleviate stress.     

Stress management with adolescents at the junior high transition: an outcome evaluation of coping skills intervention

This paper reports an outcome study of coping skills intervention to help adolescents manage stress associated with the transition from elementary school to junior high. In a randomized design, sixth grade students from four elementary schools were pretested, then two schools each were assigned to an intervention condition and to a control condition. Intervention condition subjects received eight sessions of instruction and practice in coping skills intervention. Following intervention, all subjects were posttested. At posttest and relative to control condition subjects, intervention condition subjects scored more positively on measures of problem solving, assertive direct refusals, adequacy of information about junior high school, ability to handle stress, ability to deal with peer pressure, and general readiness for junior high school.     

耐多药肺结核患者心理健康状况调查及与应对方式、社会支持的相关性研究

摘要 目的：探讨耐多药肺结核患者心理健康状况的影响因素,分析其及与应对方式、社会支持的相关性。方法：选择2018年4月至2020年5月我院诊治的101例耐多药肺结核患者作为观察组,选择同期99例敏感肺结核患者作为对照组。两组均测评症状自评量表-90(SCL-90)评分、医学应对问卷(MCMQ)评分以及社会支持评定量表(SSRS)评分,分析SCL-90总评分与MCMQ各因子评分、SSRS总评分的相关性,采用Logistic回归模型分析心理健康状况的影响因素。结果：与对照组相比,观察组的躯体化、人际关系、抑郁、焦虑、敌对性、恐怖和精神病性评分以及总评分明显提高（P<0.05）。与对照组相比,观察组的面对评分、客观支持、主观支持、支持利用度评分以及总评分均降低（P<0.05）。Pearson相关性分析显示,SCL-90总评分与MCMQ评分中的回避和屈服评分呈正相关性（r=0.386、0.311,均P<0.05）,SCL-90总评分与SSRS总评分呈负相关（r=-0.332,P<0.05）。多因素Logistic回归分析显示,经济状况差、躯体健康状况差、病情严重、睡眠质量差和生活满意度低是耐多药肺结核患者心理健康不良的独立危险因素（P<0.05）。结论：耐多药肺结核患者心理健康状况差,应对方式选择面对较少,总体社会支持水平较低,患者的心理健康状况与应对方式、社会支持存在一定的相关性。在提供躯体性治疗的基础上,应结合患者的心理健康状况及相关危险因素给予适当干预。     

噪声刺激后豚鼠耳蜗抗氧化能力的变化和α-硫辛酸对声损伤的保护作用

实验探讨了声刺激后豚鼠血清总抗氧化能力(total antioxidant capacity,TAC)和耳蜗组织一氧化氮(nitricoxide,NO)含量的变化及α-硫辛酸的抗氧化和对声损伤的保护作用。将豚鼠(350-400 g)随机分为无噪声对照组(n=20)、噪声+生理盐水组(n=20)和噪声+α-硫辛酸组(n=20)。噪声刺激(4.kHz倍频程,115 dB SPL 5 h)结束后立即测试脑于诱发电位(auditory brainstem responses,ABRs),取血清测TAC,制备耳蜗组织匀浆测NO的水平。所得结果如下:(1)无噪声对照组,动物听阈无明显变化;噪声刺激后生理盐水组,听阈上升的幅度明显高于α-硫辛酸组(P<0.05)。(2)噪声+生理盐水组,TAlC明显低于无噪声对照组(P<0.05);噪声+α-硫辛酸组同噪声+生理盐水组相比,TAC明显升高(P<0.05),同无噪声对照组相比,无显著性差异(P>0.05)。(3)噪声+生理盐水组,NO含量高于无噪声对照组(P<0.05);噪声+α-硫辛酸组同噪声+生理盐水组相比,NO含量明显减少(P<0.05),同无噪声对照组相比,差异无显著性(P>0.05)。上述结果提示,噪声刺激后血清TAC降低,耳蜗组织内NO含量增加;α-硫辛酸可通过抗氧化机制对噪声性听力损伤(noise induced hearing loss,NIHL)发挥保护作用。     

强噪声对豚鼠认知功能和血清某些生化指标的影响

目的：探讨强噪声对豚鼠认知功能和血清应激激素、代谢酶、神经肽、脑红蛋白等的影响,筛选噪声性认知功能损伤的敏感指标。方法：将24只豚鼠进行5 d的认知功能训练,第6天随机分为2组（n=12）：噪声组和对照组。噪声组在120 dB噪声下连续暴露4h后,用Morris水迷宫测试豚鼠的认知能力;用Elisa试剂盒检测豚鼠血清神经肽Y（NPY）、神经肽P（NPP）、脑红蛋白（NGB）、C反应蛋白（CRP）、皮质醇（CORT）、促肾上腺皮质激素（ACTH）、促肾上腺皮质激素释放激素（CRH）、肾上腺素（E）、去甲肾上腺素（NE）、血管紧张素Ⅱ（AngⅡ）、醛固酮（ALD）、催产素（OT）、血管升压素（VAP）含量、谷草转氨酶（ALT）、谷丙转氨酶（AST）、乳酸脱氢酶（LDH）、肌酸激酶（CK）的活性;用回归分析评价各项敏感指标对认知功能的影响及程度。结果：Morris水迷宫测试显示,与对照组相比,噪声组豚鼠的平均逃避潜伏期明显延长,跨越平台次数和目标象限停留时间均明显降低（P<0.01）。Elisa检测发现,除AngⅡ外,噪声组豚鼠血清中上述指标均与对照组有明显的统计学差异（P<0.05,P<0.01）,其中变化显著且对认知功能影响较大的指标依次为CORT、NPY、NE、NGB、NPP、CK。结论：强噪声急性暴露引起豚鼠认知功能显著下降,可能与外周血应激激素、代谢酶、神经肽、脑红蛋白等生化指标的异常有关,并初步筛选出了CORT、NPY、NE、NGB、NPP、CK等与噪声性认知功能损伤有关的敏感指标群。     

Biofeedback-assisted relaxation: effects on phagocytic capacity

The purpose of this study was to investigate whether subjects who self-report high levels of stress have lower immunity, and whether "low"-immunity subjects under "high" stress could enhance phagocytic activity through biofeedback-assisted relaxation (BAR). During Phase 1, the level of stress and the level of phagocytic immune functioning (nitroblue tetrazolium test) were assessed as "high" or "low." Significant chi-square analysis (chi 2 = 3.8624, df = 1, p less than .05) showed that subjects with "high" stress had "low" immunity. Sixteen "high"-stress, "low"-immunity subjects were randomly assigned to BAR and control groups during Phase 2. Following treatment, NBT changes showed significant increases (F = 11.11, p less than .003) for experimental group as compared to control group. White blood cell count and white blood cell differential were unchanged across blood samples for both groups. Experimental subjects reported significant decreases in tension-anxiety and increases in overall coping. BAR was concluded to have improved coping skills and phagocytic capacity. BAR affected the quality, rather than the quantity, of phagocytic neutrophils.     

Therapeutic effects of orally administrated antioxidant drugs on acute noise-induced hearing loss

Abstract

Objective. The objective of this study was to investigate the dose-dependent therapeutic effect of the orally administrated antioxidant drugs [4-hydroxy alpha-phenyl-tert-butylnitrone (4-OHPBN) and N-acetyl-L-cysteine (NAC)] on acute noise-induced hearing loss because oral administration is the most commonly used method of drug administration due to its convenience, safety, and economical efficiency. Methods. Thirty chinchilla were exposed to a 105 dB octave band noise centered at 4 kHz for 6 h and randomly assigned to a control group (saline only) and three experimental groups [4-OHPBN (10 mg/kg) plus NAC (20 mg/kg), 4-OHPBN (20 mg/kg) plus NAC (50 mg/kg), and 4-OHPBN (50 mg/kg) plus NAC (100 mg/kg)]. The drugs were orally administrated beginning 4 h after noise exposure and then administered twice daily for the next 2 days. Permanent auditory brainstem response threshold shifts, distortion product otoacoustic emission threshold shifts, and the percentage of missing outer hair cell were determined. Results. The oral administration significantly reduced permanent hearing threshold shift, distortion product otoacoustic emission threshold shift, and the percentage of missing outer hair cell in a dose-dependent manner. Discussion. This result demonstrates that orally administered drugs can treat acute noise-induced hearing loss in a dose-dependent manner. This suggests that oral administration was effective in treating acute noise-induced hearing loss as in intraperitoneal administration.     

Association of hsp70 polymorphisms with risk of noise-induced hearing loss in Chinese automobile workers

Severe noise exposure can induce heat shock proteins (Hsps), and exposure to moderate noise has been reported to confer protection against noise-induced damage to hearing. Whether there is any association of genetic variation in both constitutive and inducible hsp70 genes with noise-induced hearing loss (NIHL) is presently unknown. Using polymerase chain reaction-restriction fragment length polymorphism, we genotyped 3 polymorphisms (+190A/ B, +1267A/B, and +2437A/B) in the hsp70-1 (rs1043618), hsp70-2 (rs1061581), and hsp70-hom (rs2227956) genes, respectively, and investigated the associations of these polymorphisms with risk of developing NIHL in 194 automobile workers working in a similar noise environment as evaluated by audiological assessment. Multivariate logistic regression models were used to assess the associations with the risk genotypes, and Whap software was used to analyze their haplotypes. Our results showed that there was no statistically significant difference in the genotype and allele distributions of hsp70-1, hsp70-2, and hsp70-hom between the NIHL group and the normal group (P > 0.05) with and without adjustment for age, sex, smoking, history of explosive noise exposure, and cumulative noise exposure. However, haplotype analysis revealed that the Hap5 (ie, haplotype +190A/+1267B/+2437A) and Hap6 (ie, haplotype +190A/+1267B/+2437B) were significantly more frequent in the NIHL group than in the normal group (20/9, P = 0.022, and 7/0, P = 0.005, respectively). Compared with Hap1 (ie, +190A/+1267A/+2437A), Hap5 was associated with a nearly 3-fold increased risk of NIHL (adjusted odds ratio, 2.67; 95% confidence interval, 1.13-6.27). Seven of the NIHL patients had Hap6, but none of the controls had this haplotype. Our results suggest that some haplotypes of the hsp70 genes may be associated with a higher susceptibility to NIHL.     

Stochastic resonance induced by fluctuation in liquid membrane oscillator without input signals

We investigated numerically the dynamic behavior of the oil/water liquid membrane, which is a promising model for excitable bio-membrane. When we use noise to modulate the parameters in simulation, noise-induced coherent oscillation is observed. With the increment of the noise intensity, the coherence of noise-induced oscillation can go through a maximum, which indicating the occurrence of stochastic resonance (SR) without input signals. We compared the SR effects under the condition that noise is added to different control parameters. When noise was added to both of the parameters, a complicated SR-like phenomemon was observed. The interaction of coherent SRs induced by two independent noises is discussed. The possibly constructive role of noise in some sensory cells is discussed also.     

Effects of Minority Stress,Group-Level Coping,and Social Support on Mental Health of German Gay Men

Objective

According to epidemiological studies, gay men are at a higher risk of mental disorders than heterosexual men. In the current study, the minority stress theory was investigated in German gay men: 1) it was hypothesized that minority stressors would positively predict mental health problems and that 2) group-level coping and social support variables would moderate these predictions negatively.

Methods

Data from 1,188 German self-identified gay men were collected online. The questionnaire included items about socio-demographics, minority stress (victimization, rejection sensitivity, and internalized homonegativity), group-level coping (disclosure of sexual orientation, homopositivity, gay affirmation, gay rights support, and gay rights activism), and social support (gay social support and non-gay social support). A moderated multiple regression was conducted.

Results

Minority stressors positively predicted mental health problems. Group-level coping did not interact with minority stressors, with the exception of disclosure and homopositivity interacting marginally with some minority stressors. Further, only two interactions were found for social support variables and minority stress, one of them marginal. Gay and non-gay social support inversely predicted mental health problems. In addition, disclosure and homopositivity marginally predicted mental health problems.

Conclusions

The findings imply that the minority stress theory should be modified. Disclosure does not have a relevant effect on mental health, while social support variables directly influence mental health of gay men. Group-level coping does not interact with minority stressors relevantly, and only one relevant interaction between social support and minority stress was found. Further longitudinal or experimental replication is needed before transferring the results to mental health interventions and prevention strategies for gay men.     

Race differences in the association of oxidative stress with insulin sensitivity in African- and European-American women

Excessive metabolism of glucose and/or fatty acids may impair insulin signaling by increasing oxidative stress. The objective of this study was to examine the association between insulin sensitivity and protein carbonyls, a systemic marker of oxidative stress, in healthy, nondiabetic women, and to determine if the relationship differed with race. Subjects were 25 African-Americans (AA, BMI 28.4 ± 6.2 kg/m(2), range 18.8-42.6 kg/m(2); age 33.1 ± 13.5 years, range 18-58 years) and 28 European-Americans (EA, BMI 26.2 ± 5.9 kg/m(2), range 18.7-48.4 kg/m(2); age 31.6 ± 12.4 years, range 19-58 years). Insulin sensitivity was determined using an intravenous glucose tolerance test incorporating [6,6-(2)H(2)]-glucose, and a two-compartment mathematical model. Multiple linear regression results indicated that insulin sensitivity was inversely associated with protein carbonyls in AA (standardized regression coefficient -0.47, P < 0.05) but not EA (0.01, P = 0.945), after adjusting for %body fat. In contrast, %body fat was significantly and positively associated with insulin sensitivity in EA (-0.54, P < 0.01) but not AA (-0.24, P = 0.196). Protein carbonyls were associated with free fatty acids (FFA) in AA (r = 0.58, P < 0.01) but not EA (r = -0.11, P = 0.59). When subjects were divided based on median levels of fasting glucose and FFA, those with higher glucose/FFA concentrations had a significantly greater concentration of circulating protein carbonyls compared to those with lower glucose/FFA concentrations (P < 0.05). These results suggest that oxidative stress independently contributes to insulin sensitivity among AA women. Further, this association in AA may be mediated by circulating FFA and/or glucose.     

Project NEMESIS: perception of a 50 Hz electric and magnetic field at low intensities (laboratory experiment).

The Electrical Hypersensitivity Syndrome (EHS) is a condition where people suffer from various nonspecific health symptoms attributed to an assumed adverse effect of electric and magnetic fields (EMF). Many EHS patients report the ability to consciously perceive EMF at very low intensities. The existence of a direct EMF perception could be the key to explain at least partially the aetiology of EHS through stress mechanisms and allow the comparison with well known environmental stressors such as noise or odor. The double blind laboratory experiment tested the hypothesis that there are subjects with the ability to perceive 50 Hz EMF at 100 V/m and 6 microT (EMF sensitive) and to investigate the prevalence of EMF sensitivity in a group consisting of subjects with or without self-reported EHS. A total of 63 volunteers, 49 with EHS and 14 controls, took part in the EMF perception experiment, where 10 sham and 10 exposed 2 min blocks had to be judged in randomized sequence (field on/field off). Seven out of 63 subjects reached a statistically significant result which points to the existence of a small EMF sensitive subgroup within the study group. There was no relevant difference between the subjects with self reported EHS and those without in terms of the success rate in the field perception experiment, as well as the number and types of symptoms encountered during the test. The results of the EMF perception experiment suggest that EHS is not a prerequisite for the ability to consciously perceive weak EMF and vice versa.     

变压器噪声暴露对豚鼠应激、肝肾及免疫功能的影响

目的:探讨短时间内变压器噪声暴露对豚鼠应激、肝肾及免疫功能的影响。方法:取32只健康成年(5-6月龄)豚鼠随机分为实验组和对照组,每组16只。实验组给予录制的变压器噪声(声压级范围40.8-55 d B SPL,频谱范围150-2000 Hz)连续暴露28天,10小时/天(晚10点到早上8点),对照组在相同条件下饲养,无噪声暴露。噪声暴露结束后,对实验豚鼠的应激、肝肾及免疫功能进行定量评估比较。结果:噪声暴露28天后实验组豚鼠的应激状态指标(ACTH、血清皮质醇)与对照组比较差异无统计学意义(P0.05),主要肝肾功能指标与对照组比较差异无统计学意义(P0.05),免疫相关指标(Ig G、Ig A、Ig E、IL-1、IL-2)比较差异无统计学意义(P0.05)。结论:声压级范围为40.8-55 d B SPL、频谱范围为150~2000 Hz的变压器噪声连续暴露28天(10小时/天)对成年豚鼠应激、肝肾及免疫功能无明显影响。     

Elevated serum GGT concentrations predict reduced insulin sensitivity and increased intrahepatic lipids.

Elevated serum gamma-glutamyltransferase (GGT) concentrations have been related to features of the metabolic syndrome as well as increased risk of cardiovascular and liver disease. More recently, elevated GGT levels were shown to predict development of type 2 diabetes in a longitudinal study from Korea. The aim of the present study was to test the hypothesis that serum GGT is associated with glucose tolerance, insulin sensitivity and beta-cell function in a healthy, non-diabetic Caucasian population from the Tübingen family study. Insulin sensitivity was estimated by oGTT (n = 850) or measured by hyperinsulinemic euglycemic clamp (n = 245), respectively. A subgroup (n = 70) underwent additional determination of intrahepatic lipid content using 1H magnetic resonance spectroscopy. Serum GGT was positively correlated with two-hour glucose during oGTT (r = 0.15, p < 0.0001) and negatively correlated with insulin sensitivity from oGTT (r = -0.31, p < 0.0001) and clamp (r = -0.27, p < 0.0001). The relationship between GGT and insulin sensitivity remained significant after adjusting for sex, age, BMI, and AST using multivariate regression analysis. Inclusion of serum triglyceride levels as a parameter of lipid metabolism kept the relationship significant in the oGTT group (p < 0.0001), but not in the smaller clamp group (p = 0.11). Additionally, serum GGT was positively correlated with hepatic lipid content (r = 0.49, p < 0.001) independent of sex, age, BMI, AST or serum triglycerides. There was no significant correlation between GGT and the index for beta-cell function after adjusting for age, sex, BMI and insulin sensitivity (p = 0.74). In conclusion, elevated serum GGT levels predict glucose intolerance probably via insulin resistance rather than beta-cell dysfunction. This may be primarily related to hepatic insulin resistance and increased intrahepatic lipids. The association observed between elevated hepatic lipids and reduced insulin sensitivity might explain the increased diabetes risk observed in subjects with elevated serum GGT concentrations. In the absence of overt liver disease, elevated serum GGT concentrations may point the clinician to incipient disturbances in the glucose metabolism.