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101.

Purpose:

This research was done to assess levels of psychosocial stress and related hazards [(burnout, depression, and posttraumatic stress disorder (PTSD)] among emergency medical responders (EMRs).

Materials and Methods:

A comparative cross-sectional study was conducted upon (140) EMRs and a comparative group composed of (140) nonemergency workers. The groups studied were subjected to semistructured questionnaire including demographic data, survey for job stressors, Maslach burn out inventory (MBI), Beck depression inventory (BDI), and Davidson Trauma scale for PTSD.

Results:

The most severe acute stressors among EMRs were dealing with traumatic events (88.57%), followed by dealing with serious accidents (87.8%) and young victims (87.14%). Chronic stressors were more commonly reported among EMRs with statistically significant differences (P < 0.05) except for social support with colleagues and supervisors. EMRs had statistically significant higher levels of emotional exhaustion (EE) (20%) and depersonalization (DP) (9.3%) compared with comparative group (4.3%, 1.4% respectively). Also, there was no statistically significant difference between two groups as regards lower personal achievement or depression symptoms (P > 0.05). There was increased risk of PTSD for those who had higher stress levels from death of colleagues [odds ratio (OR) [95% confidence interval (CI)] = 2.2 (0.7-7.6), exposure to verbal or physical assault OR (95% CI) = 1.6 (0.5-4.4) and dealing with psychiatric OR (95% CI) 1.4 (0.53.7) (P > 0.05)

Conclusion:

EMRs group had more frequent exposure to both acute and chronic work-related stressors than comparative group. Also, EMRs had higher levels of EE, DP, and PTSD compared with comparative group. EMRs are in need for stress management program for prevention these of stress related hazards on health and work performance.  相似文献   
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Retinal arterial macroaneurysms with supravalvular pulmonic stenosis (RAMSVPS), also known as Familial Retinal Arterial Macroaneurysms (FRAM) syndrome, is a very rare multisystem disorder. Here, we present a case series comprising ophthalmologic and systemic evaluation of patients homozygous for RAMSVPS syndrome causative IGFBP7 variant. New clinical details on 22 previously published and 8 previously unpublished patients are described. Age at first presentation ranged from 1 to 34 years. The classical feature of macroaneurysms and vascular beading involving the retinal arteries was universal. Follow up extending up to 14 years after initial diagnosis revealed recurrent episodes of bleeding and leakage from macroaneurysms in 55% and 59% of patients, respectively. The majority of patients who underwent echocardiography (18/23) showed evidence of heart involvement, most characteristically pulmonary (valvular or supravalvular) stenosis, often requiring surgical correction (12/18). Four patients died in the course of the study from complications of pulmonary stenosis, cerebral hemorrhage, and cardiac complications. Liver involvement (usually cirrhosis) was observed in eight patients. Cerebral vascular involvement was observed in one patient, and stroke was observed in two. We conclude that RAMSVPS is a recognizable syndrome characterized by a high burden of ocular and systemic morbidity, and risk of premature death. Recommendations are proposed for early detection and management of these complications.  相似文献   
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ObjectivesTo assess serum 25-hydroxycholecalciferol (25-OH vitamin D) levels in Jordanian children with bronchial asthma, and to examine correlations between 25-OH vitamin D levels and asthma severity and control.MethodsA cross-sectional study was conducted at the Paediatric Chest Clinic, Al-Karak Governmental Hospital, Southern Jordan, between May 2015 and February 2016. Serum 25-hydroxyvitamin D level was determined in children aged 1–14 years diagnosed with bronchial asthma (6–14 years) or recurrent wheezing episodes (<6 years). Asthma severity was determined based on the Global Initiative for Asthma assessment, the Asthma Control Test, and the Childhood Asthma Control Test. Demographic and clinical characteristics were compared between patients with low and normal 25-OH vitamin D levels, and correlations between asthma severity and 25-OH vitamin D level were assessed.ResultsOut of 98 included children, 25-OH vitamin D levels were deficient and insufficient in 41 (41.8%) and 34 (34.7%) children, respectively. Only 23 (23.5%) had sufficient 25-OH vitamin D levels. A significant correlation was found between severity of asthma symptoms and 25-OH vitamin D deficiency.Conclusion25-OH vitamin D deficiency is highly prevalent in Jordanian children with bronchial asthma and correlates significantly with asthma severity.  相似文献   
107.
Liposomes are becoming increasingly important as drug delivery systems, to target a drug to specific cells and tissues and thereby protecting the recipient from toxic effects of the contained drug. Liposome preparations have been described to activate complement. In this study, we have investigated complement activation triggered by neutral dimyristoyl-phosphocholine (DMPC) liposomes in human plasma and whole-blood systems. Incubation in plasma led to the generation of complement activation products (C3a and sC5b-9). Unexpectedly, investigations of surface-bound C3 revealed contact activated, conformationally changed C3 molecules on the liposomes. These changes were characterized by Western blotting with C3 monoclonal antibodies, and by incubating liposomes with purified native C3 and factors I and H. Quartz crystal microbalance analysis confirmed binding of C3 to planar DMPC surfaces. In addition, we demonstrated that DMPC liposomes bound to or were phagocytized by granulocytes in a complement-dependent manner, as evidenced by the use of complement inhibitors. In summary, we have shown that C3 is activated both by convertase-dependent cleavage, preferentially in the fluid phase, by mechanisms which are not well elucidated, and also by contact activation into C3(H2O) on the DMPC surface. In particular, this contact activation has implications for the therapeutic regulation of complement activation during liposome treatment.  相似文献   
108.
The effect of misoprostol, a synthetic prostaglandin E1 analog, on the development of oxidative stress induced in mice with lipopolysaccharide (LPS) endotoxin was investigated. Misoprostol was administered by intraperitoneal route (i.p.) at doses of 10, 100, or 1,000 μg/kg at the time of LPS injection (200 μg/kg, i.p.). Mice were euthanized 4 h later. Lipid peroxidation (malondialdehyde; MDA), reduced glutathione (GSH), nitric oxide (nitrite/nitrate) levels as well as paraoxonase activity were measured in brain and liver. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities as well as DNA fragmentation were determined in the liver. The administration of LPS increased oxidative stress both in the brain and liver tissue. There were significantly increased MDA and nitrite and decreased GSH and PON1 activity in the brain and liver, respectively. In addition, LPS was associated with markedly elevated plasma ALT and AST level as well as increased liver DNA fragmentation. The administration of misoprostol at 100 or 1,000 μg/kg decreased brain MDA by 17.6 and 30 %, increased GSH by 29.8 and 33.3 %, and decreased nitric oxide by 21.74 and 42.5 %, respectively, compared with the lipopolysaccharide control group. Liver MDA decreased by 27 %, GSH increased by 47.7 %, and nitric oxide decreased by 37.2 % with misoprostol at 1,000 μg/kg. Paraoxonase activity increased in both the brain and liver by misoprostol administration. The increase in liver AST and ALT and DNA fragmentation after endotoxin administration was normalized by misoprostol. These results indicate that misoprostol can alleviate oxidative stress in the presence of a mild systemic inflammatory illness, indicating a new and potentially important therapeutic application for the drug.  相似文献   
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