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Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
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BACKGROUND: Stressful conditions lead to formation of excessive free radicals, and lipid peroxidation is one of the major outcomes of free radical-mediated injury that directly damages membranes and generates a number of secondary products. OBJECTIVES: To determine the levels of malondialdehyde, an end product of lipid peroxidation, according to demographic and occupational variables in workers of a prehospital emergency service and to analyse the relationship between malondialdehyde levels and burnout. MATERIAL AND METHODS: One hundred and eleven healthy workers of a prehospital emergency service and eighty aged-matched healthy individuals of both sexes as a control group were surveyed. Malondialdehyde levels were measured by the Bull and Marnett method. To measure burnout, the Maslach Burnout Inventory was used. RESULTS: Professional category is associated with lipid peroxidation and burnout levels (Malondialdehyde levels were: physicians 338.10+/-14.47, nurses 329.17+/-12.62 and technicians 296.74+/-14.28; burnout levels were: physicians 41.29+/-3.59, nurses 37.38+/-6.05 and technicians 35.33+/-5.87). Working at night and in the evening increased malondialdehyde and burnout levels. Malondialdehyde levels increase with age. No significant variations with respect to sex were detected. Significant variations in malondialdehyde levels were detected between singles (303.13+/-12.74) and married people (344.43+/-13.43) but not with respect to divorcees (326.44+/-11.74). Significant differences were detected in erythrocyte malondialdehyde levels between smokers (341.37+/-17.09) and nonsmokers (302.21+/-12.38), but not for alcohol consumption. CONCLUSIONS: These findings suggest a positive correlation between malondialdehyde, a biomarker of lipid peroxidation and occupational stress, as estimated by elements of the Maslach Burnout Inventory, and oxidative stress.  相似文献   
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STUDY OBJECTIVES: Use of fast track has been shown to improve the emergency department flow of less urgent patients. It has been speculated, however, that this could negatively affect the care of urgent patients. The objective of this study was to determine whether a dedicated fast track for less urgent patients [Canadian Triage and Acuity scale category 4/5 (CTAS 4/5)] affected (1) the time to assessment for urgent patients (CTAS 3), (2) the length of stay for less urgent patients (CTAS 4 and 5), and (3) the left-without-being-seen rate. METHODS: In June 2003, fast track was opened in our emergency department from 13:00 to 19:00 h. A before-after intervention comparison analysis was completed for 1 week in Aug 2002 and the same week in Aug 2003. Data collected included (1) time to assessment of CTAS 3 patients, (2) the length of stay for CTAS 4/5 patients, and (3) percentage of patients who left without being seen. RESULTS: A total of 368 patients were reviewed for 2002 and 380 patients were reviewed for 2003. Median time to assessment of CTAS 3 patients presenting from 13:00 to 19:00 h was reduced from 66 min (Interquartile range: 40, 94 min) in 2002 to 60 min (IQR: 38, 108 min) after fast track was open in 2003 (P = 0.95). Median length of stay of CTAS 4 and 5 patients was reduced from 170 min (IQR: 111, 256 min) to 110 min (IQR: 69, 185 min) (P < 0.001). The overall left-without-being-seen rate decreased from 5% (20/368) to 2% (9/380). CONCLUSION: A dedicated fast track for CTAS 4/5 patients can reduce the length of stay and the left-without-being-seen rate with no impact on CTAS 3 patients seen in the main emergency department.  相似文献   
5.
We have measured the release of adenosine and inosine from the dorsal surface of the brainstem and from within the nucleus tractus solitarii (NTS) during the defence response evoked by hypothalamic stimulation in the anaesthetised rat. At the surface of the brainstem, only release of inosine was detected on hypothalamic defence area stimulation. This inosine signal was greatly reduced by addition of the ecto-5'-nucleotidase inhibitor α,β-methylene ADP (200 μM), suggesting that the inosine arose from adenosine that was produced in the extracellular space by the prior release of ATP. By placing a microelectrode biosensor into the NTS under stereotaxic control we have recorded release of adenosine within this nucleus. By contrast to the brainstem surface, a fast increase in adenosine, accompanied only by a much smaller change in inosine levels, was seen following stimulation of the hypothalamic defence area. The release of adenosine following hypothalamic stimulation was mainly confined to a narrow region of the NTS some 500 μm in length around the level of the obex. Interestingly the release of adenosine was depletable: when the defence reaction was evoked at short time intervals, much less adenosine was released on the second stimulus. Our novel techniques have given unprecedented real-time measurement and localisation of adenosine release in vivo and demonstrate that adenosine is released at the right time and in sufficient quantities to contribute to the cardiovascular components of the defence reaction.  相似文献   
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Abstract   We evaluated the associations between glycemic therapies and prevalence of diabetic peripheral neuropathy (DPN) at baseline among participants in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial on medical and revascularization therapies for coronary artery disease (CAD) and on insulin-sensitizing vs. insulin-providing treatments for diabetes. A total of 2,368 patients with type 2 diabetes and CAD was evaluated. DPN was defined as clinical examination score >2 using the Michigan Neuropathy Screening Instrument (MNSI). DPN odds ratios across different groups of glycemic therapy were evaluated by multiple logistic regression adjusted for multiple covariates including age, sex, hemoglobin A1c (HbA1c), and diabetes duration. Fifty-one percent of BARI 2D subjects with valid baseline characteristics and MNSI scores had DPN. After adjusting for all variables, use of insulin was significantly associated with DPN (OR = 1.57, 95% CI: 1.15–2.13). Patients on sulfonylurea (SU) or combination of SU/metformin (Met)/thiazolidinediones (TZD) had marginally higher rates of DPN than the Met/TZD group. This cross-sectional study in a cohort of patients with type 2 diabetes and CAD showed association of insulin use with higher DPN prevalence, independent of disease duration, glycemic control, and other characteristics. The causality between a glycemic control strategy and DPN cannot be evaluated in this cross-sectional study, but continued assessment of DPN and randomized therapies in BARI 2D trial may provide further explanations on the development of DPN.  相似文献   
8.
L1 disease is the most common genetic cause of congenital hydrocephalus. Mutations in the L1CAM gene are associated with an overlapping clinical spectrum of four X-linked neurological conditions, characterized by hydrocephalus, mental retardation, lower limb spasticity and adducted thumbs. Brain anomalies are frequently present in L1 disease. We describe these anomalies by reporting a case of a male newborn presenting with congenital hydrocephalus along with corpus callosum agenesis and enlargement of the massa intermedia. These findings, in association with the presence of clasped thumbs, raised the suspicion of L1 disease, which was confirmed by the detection of a mutation in the L1CAM gene. In cases of congenital hydrocephalus, recognition of the brain anomalies associated with L1 disease may contribute to pursuing the genetic analysis needed for the diagnosis and genetic counseling.  相似文献   
9.
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations.  相似文献   
10.
There is no published data about associations between the state of dentition and bone mass in adolescents. The objective of this study was to investigate whether the prevalence of caries and dental malocclusion is associated with bone mass during growth. In 123 healthy Caucasian subjects (72 males, 51 females) aged 14-18 yr, DMFT figures (decayed teeth, missing teeth, filled teeth) and presence of malocclusion, according to Angle classification, were determined. Participants completed a questionnaire regarding dental hygiene, physical activity level, and consumption of sweets. Anthropometry and pubertal stages were examined. Bone mineral density (BMD) was examined using dual energy X-ray absorptiometry (DXA) in the total body, head, and lumbar spine. No association was found between DMFT (mean+/-SD: 8.33+/-3.9) and BMD or Z-scores for BMD. Malocclusion was found in 49 subjects (39.8%) and was more prevalent in females than males. Malocclusion was associated with lower total BMD independently of body size (p=0.001; Z-scores: -0.21+/-0.27 vs +0.33+/-0.17; p=0.1) in males (but not females), producing odds ratio 1.6 (95% confidence interval: 1.09-2.34%; p=0.02). Head BMD was also lower in the males with malocclusion than in those without (p=0.004). Neither caries nor the tooth loss appear to be associated with BMD during growth. Boys with malocclusion are at higher risk of reduced BMD. This suggests that inadequate bone mass accrual in males coexists with impaired growth of the masticatory system in childhood and adolescence, however, the causal pathway is unknown. Factors that produce malocclusion may also affect bone mass or size but further prospective studies are needed to evaluate the relationship.  相似文献   
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