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Melatonin reduces oxidative stress and improves vascular function in pulmonary hypertensive newborn sheep 下载免费PDF全文
Flavio Torres Alejandro González‐Candia Camilo Montt Germán Ebensperger Magdalena Chubretovic María Serón‐Ferré Roberto V. Reyes Aníbal J. Llanos Emilio A. Herrera 《Journal of pineal research》2015,58(3):362-373
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN. 相似文献
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Maria Russo Claudio Lucifora Francesco Pucciarelli Bruno Piccoli 《La Medicina del lavoro》2019,110(2):115
Background:Workplace hazards are a significant source of health impairment for workers and of financial losses for firms. EU directives on workers’ health and safety standards significantly contributed to reduce reported occupational injuries, yet the incidence and prevalence of work-related mental illness is still very high.Objectives:We investigated the association between work-related hazards and individuals’ perceived mental health. We reviewed the existing evidence on the channels through which task-related factors, adverse agents and psychosocial factors are expected to affect workers’ health, with specific regard to mental health.Methods:We used data from the fifth wave of the European Working Conditions Survey, covering over 40,000 face-to-face interviews with workers in 34 countries, which includes information on socio-demographic characteristics, firms and jobs attributes, employment status, as well as working conditions and health status. We carried out an empirical analysis with multivariate regression models in order to estimate the relationship between workers’ mental health problems and workplace risk factors.Results:21,020 interviews were used in the multivariate analysis. We found strong correlations between hazards and various indicators of mental health. Among hazardous agents, low temperatures (β=0.0287) and contact with infectious materials (β=0.0394) were positively associated with mental health outcomes. Among task/sequence-related factors, tiring or painful positions (β=0.0713), repetitive hand/arm movements (β=0.0255), working with VDUs (β=0.0301), repetitive tasks <10 min (β=0.0859) and working in evenings (β=0.00754) were positively associated with mental health. Various psychosocial risk factors related to both the content of the job (for example, frequent disruptive interruptions: β=0.219, working in free time: β=0.0759, poor work-life balance: β=0.228) as well as the job context (for example, bad employment prospects: β=0.177, low decisional autonomy: β=0.245, bad social relations: β=0.186, workplace violence: β=0.411) were positively associated with mental health. The main results of the decomposition show that an important contribution to workers’ overall mental distress at work is associated with psychosocial risk factors (up to 60% for depression/anxiety symptoms and sleep disorders), while the contribution of somatic factors is on average lower (up to 20% for overall fatigue).Conclusions:We argue that action is needed to improve workers’ mental well-being, and reduce the economic costs for both the national health system and employers. Regulations and traditional economic measures are unlikely to prove successful in providing adequate standards of primary and secondary preventive measures in the work place without an appropriate and reliable Risk Assessment Procedure.Key words: Work hazards, risk assessment, job content, mental health 相似文献
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Samira Marín-Romero Teresa Elías-Hernández María Isabel Asensio-Cruz Rocío Ortega-Rivera Raquel Morillo-Guerrero Javier Toral Emilio Montero Verónica Sánchez Elena Arellano José María Sánchez-Díaz Macarena Real-Domínguez Remedios Otero-Candelera Luis Jara-Palomares 《Archivos de bronconeumología》2019,55(12):619-626
IntroductionScales for predicting venous thromboembolism (VTE) recurrence are useful for deciding the duration of the anticoagulant treatment. Although there are several scales, the most appropriate for our setting has not been identified. For this reason, we aimed to validate the DASH prediction score and the Vienna nomogram at 12 months.MethodsThis was a retrospective study of unselected consecutive VTE patients seen between 2006 and 2014. We compared the ability of the DASH score and the Vienna nomogram to predict recurrences of VTE. The validation was performed by stratifying patients as low-risk or high-risk, according to each scale (discrimination) and comparing the observed recurrence with the expected rate (calibration).ResultsOf 353 patients evaluated, 195 were analyzed, with an average age of 53.5 ± 19 years. There were 21 recurrences in 1 year (10.8%, 95% CI: 6.8%-16%). According to the DASH score, 42% were classified as low risk, and the rate of VTE recurrence in this group was 4.9% (95% CI: 1.3%-12%) vs. the high-risk group that was 15% (95% CI: 9%-23%) (p <.05). According to the Vienna nomogram, 30% were classified as low risk, and the rate of VTE recurrence in the low risk group vs. the high risk group was 4.2% (95% CI:0.5%-14%) vs. 16.2% (95% CI: 9.9%-24.4%) (p <.05).ConclusionsOur study validates the DASH score and the Vienna nomogram in our population. The DASH prediction score may be the most advisable, both because of its simplicity and its ability to identify more low-risk patients than the Vienna nomogram (42% vs. 30%). 相似文献
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Michele D. Mignogna Stefano Fedele Lucio Lo Russo Lorenzo Lo Muzio 《Journal of oral pathology & medicine》2003,32(4):200-205
BACKGROUND: The recurrent chronic orofacial swelling caused by orofacial granulomatosis (OFG) can cause significant cosmetic and functional problems but can be prevented if the disease is diagnosed early and promptly treated. Although the enlargement of the lips is described to be the most common presenting complaint, the clinical onset of OFG may be characterized by minor associated mucosal and neurological manifestations, making early diagnosis very difficult or, sometimes, merely presumable. PATIENTS AND METHODS: We retrospectively analyzed the clinical manifestations of 19 patients with OFG, who were examined at our institution between 1998 and 2002, in order to determine their initial manifestations and presenting symptoms. RESULTS: A total of 10 patients showed classical recurrent enlargement of the lips (six lower; four upper) as presenting symptom. In the other nine patients, OFG onset was characterized by transient unilateral facial nerve palsy (two cases), intraoral manifestations (two cases), recurrent swelling of the periorbital area (two cases), of the chin (one case), of the zygomatic area (one case), and of the cheeks (one case). CONCLUSION: Our data underlined that OFG onset could be frequently characterized by widely variable, multiform, and temporary clinical findings. Involvement of atypical sites of the orofacial region and presence of single minor manifestations may occur as presenting symptoms, often preceding the development of traditional clinical findings. 相似文献
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Accuracy evaluation of image registration and segmentation tools used in conformal treatment planning of prostate cancer. 总被引:1,自引:0,他引:1
Stefania Pallotta Marta Bucciolini Serenella Russo Cinzia Talamonti Talamonti Cinzia Giampaolo Biti 《Computerized medical imaging and graphics》2006,30(1):1-7
Segmentation and registration tools are commonly used in radiotherapy for target and at risk organs localisation. In this work the performances of three different segmentation tools and of a surface matching registration technique, used on computed tomography (CT) and magnetic resonance (MR) images for the treatment planning of conformal prostate carcinoma, are studied. The accuracy of the segmentation and registration tools was evaluated by phantom experiment and on patient data, respectively. A preliminary estimate of MR image distortion was also performed. 相似文献