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131.
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Oxidatively damaged DNA in aging dyslipidemic ApoE-/- and wild-type mice   总被引:2,自引:0,他引:2  
Folkmann JK  Loft S  Møller P 《Mutagenesis》2007,22(2):105-110
The free radical theory of aging depicts an accumulation of cellular oxidatively damaged DNA. In this study, we investigated this theory in mice with knocked-out apolipoprotein E gene (ApoE(-/-)), which develops atherosclerosis and wild-type counterparts. The level of oxidatively damaged DNA was investigated as strand breaks, endonuclease III- and formamidopyrimidine DNA glycosylase-sensitive sites by the comet assay. The level of DNA damage was mainly increased with age in the liver of ApoE(-/-) mice, whereas no increase was observed in the aorta or lung of the mice. This suggests that the accumulation of oxidized DNA in the liver of dyslipidemic ApoE(-/-) mice could be secondary to dysfunction of the lipid metabolism. Visually, the aortas of the ApoE(-/-) mice were clearly atherosclerotic as indicated by rigid texture and yellowish in color. However, the unaltered levels of oxidized DNA in severely atherosclerotic aortas of old ( approximately 70 weeks) ApoE(-/-) mice indicate that oxidative stress may not be a generalized phenomenon, but rather related locally to the individual plaques. In conclusion, the results of this study suggest that dyslipidemic ApoE(-/-) mice suffer from hepatic oxidative stress in terms of oxidized DNA, and this effect could be due to the dysfunction of lipid metabolism.  相似文献   
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The Jefferson Scale of Empathy (JSE) is a broadly used instrument developed to measure empathy in the context of health professions education and patient care. Evidence in support of psychometrics of the JSE has been reported in health professions students and practitioners with the exception of osteopathic medical students. This study was designed to examine measurement properties, underlying components, and latent variable structure of the JSE in a nationwide sample of first-year matriculants at U.S. colleges of osteopathic medicine, and to develop a national norm table for the assessment of JSE scores. A web-based survey was administered at the beginning of the 2017–2018 academic year which included the JSE, a scale to detect “good impression” responses, and demographic/background information. Usable surveys were received from 6009 students enrolled in 41 college campuses (median response rate?=?92%). The JSE mean score and standard deviation for the sample were 116.54 and 10.85, respectively. Item-total score correlations were positive and statistically significant (p?<?0.01), and Cronbach α?=?0.82. Significant gender differences were observed on the JSE scores in favor of women. Also, significant differences were found on item scores between top and bottom third scorers on the JSE. Three factors of Perspective Taking, Compassionate Care, and Walking in Patient’s Shoes emerged in an exploratory factor analysis by using half of the sample. Results of confirmatory factor analysis with another half of the sample confirmed the 3-factor model. We also developed a national norm table which is the first to assess students’ JSE scores against national data.  相似文献   
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Objectives: The aims of this study were to examine job resources, work engagement and Finnish dairy farmers’ preferences concerning methods to enhance overall well-being while working on farms.

Methods: A postal survey yielded 265 completed questionnaires from 188 dairy farms. The sample was assessed as representative of Finnish dairy farmers. Exploratory factor analysis and a linear mixed model were utilized during the data analyzing process.

Results: The variables lowering work engagement were stressors related to the workload and problems with health. Elevated work engagement was associated with the factors work with farm animals and family. The most important resource variables were “child or children,” “own family,” and “animal health.” Female dairy farmers considered resource variables related to the family, love, and work with cattle as significantly more important than male dairy farmers. Male dairy farmers experienced higher work engagement and, concerning the dimensions, especially higher dedication and absorption than male respondents in a reference sample of workers in difference occupations. A sustainable farm economy and the possibility to have a holiday period were the most important methods to improve overall well-being on dairy farms.

Conclusion: The results indicate that the family, working with cattle, healthy farm animals, a reasonable workload, and a sustainable farm economy have the capacity to create positive impacts on well-being among dairy farmers. Well-being on farms is a part of sustainable food production.  相似文献   

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BACKGROUND: Studies have shown that adverse workplace factors can increase the risk of ill-health in hospital workers, but more comprehensive measures of the psychosocial work environment are needed. OBJECTIVES: To test a comprehensive and theory-based psychosocial work environment questionnaire and analyze associations with mental health in a sample of Danish hospital workers. DESIGN AND PARTICIPANTS: Questionnaire-based cross-sectional study with 343 female employees from a large Danish hospital, including patient care workers (nurses, nurse assistants, midwives) and laboratory technicians. METHODS: The psychosocial work environment was measured with 14 scales from the Copenhagen psychosocial questionnaire, version I, covering three main areas: demands at work, work organization and interpersonal relations at work. We further measured self-rated mental health and sociodemographic and employment characteristics of the participants. Cronbach's alphas, analyses of covariance, one-sample t-tests, partial correlations and linear regression models were used to analyze data. RESULTS: Of the 14 work psychosocial workplace scales 12 showed a satisfactory internal consistency (alpha>0.70). Patient care workers had more quantitative, emotional and cognitive demands (all p-values <0.001), higher work pace (p<0.001) and more role conflicts (p=0.01) than laboratory technicians, but also better work organization, including more influence at work, better possibilities for development and a higher meaning of work (all p-values <0.001). Both patient care workers and laboratory technicians had substantially higher scores on the demand scales and lower scores on the influence at work scale than the general Danish working population. Further analyses showed that high levels of demands at work and low levels of work organization and problematic interpersonal relations at work were associated with lower self-rated mental health. CONCLUSION: The Copenhagen psychosocial questionnaire is a suitable instrument to measure the psychosocial work environment of hospital workers. The comprehensive assessment of the psychosocial work environment helps tailoring interventions to the specific needs of different occupational groups.  相似文献   
138.
Background: The impact of total body weight (TBW) on the development of acute kidney injury (AKI) associated with gram-negative bacteremia has not been previously evaluated.

Methods: The cohort included 323 patients >/ = 18 years old with gram-negative bacteremia (1/1/2008–8/31/2011) who received >/ = 48 hours of antibiotics. We compared the incidence of AKI in patients with a TBW </ = 80kg vs. >80kg with a multivariable stepwise logistic regression adjusting for age >/ = 70 years, baseline serum creatinine of > 2.0 mg/dl, and receipt of a vasopressor. AKI was defined as an increase of 0.5 mg/dL or a > 50% increase from baseline for at least two consecutive days.

Results: The cohort was 62% TBW </ = 80kg and 38% TBW >80kg. TBW >80kg patients had higher risk of AKI (24% vs. 9%, p < 0.001), which was significant in the multivariable analysis (OR 3.41, 95% CI 1.73–6.73). A baseline serum creatinine of > 2.0 mg/dl and vasopressor use were also independently associated with AKI.

Conclusions: TBW >80kg was associated with the development of AKI. However, the mechanism for this association is not clear.  相似文献   

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Cationic computed tomography contrast agents are more sensitive for detecting cartilage degeneration than anionic or non-ionic agents. However, osteoarthritis-related loss of proteoglycans and increase in water content contrarily affect the diffusion of cationic contrast agents, limiting their sensitivity. The quantitative dual-energy computed tomography technique allows the simultaneous determination of the partitions of iodine-based cationic (CA4+) and gadolinium-based non-ionic (gadoteridol) agents in cartilage at diffusion equilibrium. Normalizing the cationic agent partition at diffusion equilibrium with that of the non-ionic agent improves diagnostic sensitivity. We hypothesize that this sensitivity improvement is also prominent during early diffusion time points and that the technique is applicable during contrast agent diffusion. To investigate the validity of this hypothesis, osteochondral plugs (d = 8 mm, N = 33), extracted from human cadaver (n = 4) knee joints, were immersed in a contrast agent bath (a mixture of CA4+ and gadoteridol) and imaged using the technique at multiple time points until diffusion equilibrium. Biomechanical testing and histological analysis were conducted for reference. Quantitative dual-energy computed tomography technique enabled earlier determination of cartilage proteoglycan content over single contrast. The correlation coefficient between human articular cartilage proteoglycan content and CA4+ partition increased with the contrast agent diffusion time. Gadoteridol normalized CA4+ partition correlated significantly (P < .05) with Mankin score at all time points and with proteoglycan content after 4 hours. The technique is applicable during diffusion, and normalization with gadoteridol partition improves the sensitivity of the CA4+ contrast agent.  相似文献   
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