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1.
2.

Background

The psychiatric ward is a place where all forms of violence are treated. Occasionally, this violence involves acts of aggression between patients in emergency psychiatric units or hospital wards. Such events can lead to the development or worsening of posttraumatic stress disorder.

Methods

To establish the context, we first examined the epidemiology data concerning posttraumatic stress disorder in psychiatric patients who were frequently exposed to assaults. Secondly, we examined the issue of sexual and physical assaults between patients receiving treatment in a psychiatric ward. In this context, we studied possible occurrence of posttraumatic stress disorder associated with exposure to assaults of this kind.

Results

In certain cases, potentially traumatic exposure to violence was unknown to the medical staff or not taken into consideration. This would induce a risk of later development of posttraumatic stress disorder that would not be treated during the stay in psychiatry.

Conclusion

To date, few scientific studies have focused on the proportion of patients assaulted by other patients during treatment in a psychiatric ward and the subsequent development of peritraumatic reactions and/or posttraumatic stress disorder associated with these assaults. We know that an insufficient number of public and private health institutions report the existence of such facts to the competent authorities. Also, a minority of clinicians and caregivers are trained in screening and management of trauma victims. Yet, these issues are particularly relevant in the scope of public health and health promotion.  相似文献   
3.
Context: MOTILIPERM was prepared as a mixture of extracts of three medicinal herbs [roots of Morinda officinalis How (Rubiaceae), outer scales of Allium cepa L. (Liliaceae) and seeds of Cuscuta chinensis Lamark (Convolvulaceae)].

Objective: To investigate the role of reactive oxygen species (ROS)-based endoplasmic reticulum (ER) stress in a rat model of varicocele and the therapeutic efficacy of MOTILIPERM in this model.

Materials and methods: Sixty male rats were divided into five experimental groups: a normal control group (CTR?+?vehicle), a control group administered MOTILIPERM 200?mg/kg (CTR?+?M 200), a varicocele-induced control group (VC?+?vehicle) and two varicocele-induced groups administered MOTILIPERM 100 (VC?+?M 100) or 200 (VC?+?M 200) mg/kg for 4 weeks. Testis weights were recorded and serums were assayed for hormone concentrations. Tissues were subjected to semen analysis, histopathology, analyses of ER response protein expression levels and oxidative stress were assessed by measuring ROS, reactive nitrogen species (RNS), malondialdehyde (MDA) level and ratios of total glutathione (GSH)/oxidized GSH (GSSG).

Results: MOTILIPERM treatment of varicocele-induced groups significantly increased left testis weight, testosterone level, sperm motility, count and spermatogenic cell density. ER-response protein expression levels were dose-dependently decreased in VC?+?M 200 group compared with VC?+?vehicle group. MOTILIPERM treatment also decreased MDA and ROS/RNS level but increased GSH/GSSG ratio.

Discussion and conclusions: This study suggests that ROS-related ER stress may play a major role in varicocele-induced infertility and MOTILIPERM, a novel compound targeting ROS-based ER stress, may be therapeutically useful in treatment of varicocele, or as a supplement for the treatment of infertility.  相似文献   
4.
Introduction: HIV-1-infected smokers are at risk of oxidative damage to neuronal cells in the central nervous system by both HIV-1 and cigarette smoke. Since neurons have a weak antioxidant defense system, they mostly depend on glial cells, particularly astrocytes, for protection against oxidative damage and neurotoxicity. Astrocytes augment the neuronal antioxidant system by supplying cysteine-containing products for glutathione synthesis, antioxidant enzymes such as SOD and catalase, glucose for antioxidant regeneration via the pentose-phosphate pathway, and by recycling of ascorbic acid.

Areas covered: The transport of antioxidants and energy substrates from astrocytes to neurons could possibly occur via extracellular nanovesicles called exosomes. This review highlights the neuroprotective potential of exosomes derived from astrocytes against smoking-induced oxidative stress, HIV-1 replication, and subsequent neurotoxicity observed in HIV-1-positive smokers.

Expert opinion: During stress conditions, the antioxidants released from astrocytes either via extracellular fluid or exosomes to neurons may not be sufficient to provide neuroprotection. Therefore, we put forward a novel strategy to combat oxidative stress in the central nervous system, using synthetically developed exosomes loaded with antioxidants such as glutathione and the anti-aging protein Klotho.  相似文献   

5.
Objective: Parkinson's disease (PD) is characterized by deterioration of the nigrostriatal system and associated with chronic neuroinflammation. Glial activation has been associated with regulating the survival of dopaminergic neurons and is thought to contribute to PD through the release of proinflammatory and neurotoxic factors, such as reactive nitric oxide (NO) that triggers or exacerbates neurodegeneration in PD. Polyunsaturated fatty acids (PUFAs) exert protective effects, including antiinflammatory, antiapoptotic, and antioxidant activity, and may be promising for delaying or preventing PD by attenuating neuroinflammation and preserving dopaminergic neurons. The present study investigated the effects of fish oil supplementation that was rich in PUFAs on dopaminergic neuron loss, the density of inducible nitric oxide synthase (iNOS)-immunoreactive cells, and microglia and astrocyte reactivity in the substantia nigra pars compacta (SNpc) and striatal dopaminergic fibers.

Methods: The animals were supplemented with fish oil for 50 days and subjected to unilateral intrastriatal 6-hydroxydopamine (6-OHDA)-induced lesions as a model of PD.

Results: Fish oil mitigated the loss of SNpc neurons and nerve terminals in the striatum that was caused by 6-OHDA. This protective effect was associated with reductions of the density of iNOS-immunoreactive cells and microglia and astrocyte reactivity.

Discussion: These results suggest that the antioxidant and antiinflammatory properties of fish oil supplementation are closely related to a decrease in dopaminergic damage that is caused by the 6-OHDA model of PD.  相似文献   

6.
舒郁抑斑方(SYYB)对伴有慢性心理应激的冠心病患者有较好的治疗作用。为观察SYYB对慢性心理应激促发大鼠动脉粥样硬化(athero-sclerosis,As)早期病变形成及其炎症反应的影响,采用高脂饵食+维生素D3(VD3)腹腔注射建立大鼠As早期病变模型(As),在此基础上采用不可预知慢性应激刺激法(As+CUMS),观察慢性心理应激是否加重大鼠病变及SYYB(6.6,13.2,26.4 mg·kg~(-1))的干预作用。采用悬尾实验和新奇实验法观察大鼠行为学改变,检测血清应激激素促肾上腺素(adrenocortico-tropic hormone,ACTH)、皮质醇(cortisol,Cor)、去甲肾上腺素(noradrenaline,NE)的含量,称量胸腺、肾上腺的质量,综合评价SYYB对模型大鼠心理应激的影响。取主动脉弓HE染色观察血管组织病理改变,测定血清甘油三酯(triglycerides,TG)、总胆固醇(total cholesterol,TC)、高密度脂蛋白(HDL-C),评价SYYB对大鼠As病变的影响。检测血清高敏C反应蛋白(high-sensitivity C-reactive protein,hs CRP)、白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-6(interleukin-6,IL-6),评价SYYB对As大鼠炎症反应的影响。实验结果显示,与空白组相比,As组TC,TG含量增高,HDL-C明显降低,HE染色可见主动脉壁增厚。As+CUMS组TC,TG含量显著增高,HDL-C明显降低,HE染色可见主动脉弓内膜增厚,泡沫细胞形成,行为学评价及血清应激激素检测结果显示动物存在慢性应激反应,该实验As+CUMS模型复制成功。SYYB可降低血清中TC,TG含量,减轻主动脉泡沫细胞、钙化灶及炎性细胞浸润,对血清中ACTH和Cor,NE有明显的降低作用,同时有效降低了血清中动脉粥样硬化相关的炎性标志物hs-CRP,IL-1和IL-6。提示SYYB对心理应激促发As大鼠的保护作用,其作用与改善神经-内分泌网络平衡及调节相关炎症反应有关。  相似文献   
7.
BACKGROUND: While there seems to be a common belief that psychosocial stress affects oral hygiene behavior, this assumption has rarely been proved. The present study thus aims to analyse stress effects on oral hygiene. MATERIAL AND METHODS: 16 matched pairs of medical students each consisting of 1 student participating in a major academic exam and 1 control without current academic stress, were formed on the basis of baseline plaque levels. At baseline, a professional tooth cleaning was performed. On the last day of exams, students answered questionnaires about oral hygiene during the exams and were afterwards asked to attend for a 2nd dental examination, of which they had no prior knowledge. RESULTS: On the last day of exams, approximately 6 weeks after professional tooth cleaning, 20.9+/-18.3% of control students' sites but only 10.5+/-9.3% of exam students' sites were found to be free of any plaque (p=0.022). Differences were most obvious at oral, as compared to vestibular, sites. Exam students reported a reduction in thoroughness (p=0.019) but not of frequency of oral hygiene behavior. CONCLUSION: The study strongly supports the assumption that psychosocial stress may induce neglect of oral hygiene and increase of plaque accumulation.  相似文献   
8.
OBJECTIVE: In orthodontic tooth movement, some cytokines released from periodontal ligament fibroblasts and alveolar bone osteoblasts on the pressure side can alter the normal processes of bone remodelling, resulting in physiological bone resorption. We examined the effect of compressive force and interleukin (IL)-1 type I receptor antagonist (IL-1ra) on the expression of inflammatory cytokines that promote osteoclast formation, as well as on their receptors, in osteoblastic Saos-2 cells. DESIGN: The cells were cultured in Dulbecco's modified Eagle medium containing 10% fetal bovine serum with or without continuous compressive force (0.5-3.0 g/cm(2)) and/or IL-1ra for up to 24h. The gene expression levels of the cytokines and their receptors were estimated by determining mRNA levels using real-time PCR; the protein levels were determined using ELISA or immunohistochemical staining. RESULTS: The expression of IL-1beta, IL-1 receptor, IL-6, IL-6 receptor, IL-8 receptor, IL-11 and tumor necrosis factor-alpha (TNFalpha) increased depending on the strength and duration of the compressive force, whereas the expression of IL-8, IL-11 receptor and TNFalpha receptor did not change with the application of compressive force. The expression of cytokines and their receptors produced by 3.0 g/cm(2) of compressive force decreased with the simultaneous addition of IL-1ra and the decrease was remarkable in IL-8 receptor, IL-11 and TNFalpha. CONCLUSION: These results indicate that mechanical stress induces the production of inflammatory cytokines and their receptors in osteoblasts and the phenomenon is enhanced by the autocrine action of IL-1beta, which is increased in amount by mechanical stress.  相似文献   
9.

Background & objectives

Reactive oxygen species (ROS) have been implicated in numerous human diseases, including periodontal diseases. Plasma glutathione peroxidase (eGPx) as an important antioxidant, has a protective role against ROS and is an established marker of oxidative stress. The present study evaluated the levels of eGPx in GCF to further probe into the role of oxidants and antioxidants in periodontal disease.

Methods

60 subjects were divided into three groups consisting of 20 subjects in each group based on gingival index, pocket probing depth, clinical attachment loss and radiological parameters (bone loss): healthy (group 1), gingivitis (group 2) and periodontitis (group 3), whilst, group 3 patients after the treatment constituted group 4. GCF samples were collected from all groups to estimate the levels of eGPx using ELISA.

Results

The mean eGPx concentration in GCF were observed to be the highest in group 3 i.e., 30.89 ± 4.93 ng/μl and lowest in group 1 i.e., 15.32 ± 3.06 ng/μl. The mean eGPx concentration in group 2 (23.77 ± 2.91 ng/μl) and group 4 (18.92 ± 3.53 ng/μl) fell between the highest and the lowest values.

Conclusion

This suggests that eGPx levels in GCF increase proportionally with the severity of periodontal diseases. eGPx can be considered as a marker of oxidative stress in periodontal diseases. However, controlled, longitudinal studies with larger samples have to be carried out to confirm this possibility.  相似文献   
10.
AIM: The objective was to assess whether there was a social gradient in periodontal status by job classification in Japanese male workers. MATERIAL AND METHODS: Study participants were 15,803 Japanese male workers aged 20-69 years. There were seven groups classified by jobs. Oral examinations were conducted using community periodontal index (CPI). RESULTS: The percentages of sextants with a CPI score of 3 or 4 of professionals were significantly lower than for other job classes. The gradient also existed for the percentage of sextants with CPI score 4. After adjusting for age, a history of diabetes mellitus and smoking status, those lower on the gradient, namely, drivers, service occupations, salespersons and managers were 2.0, 1.5, 1.4 and 1.4, times, respectively more likely to have one or more sextants with CPI score 3 or 4 compared with professionals. Odds ratios of having more than one or more sextants with CPI score 4 after adjusting for age, clinical history of diabetes mellitus and smoking status for drivers, service occupations, salespersons and managers were 2.1, 1.5, 1.5 and 1.2, respectively, compared with professionals. CONCLUSIONS: There was a gradient in periodontal status by job classification. Professional and office workers had better periodontal status than salespersons, service occupations and drivers.  相似文献   
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