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141.
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Voelter-Mahlknecht S Pritsch M Gigic B Langer P Loeffler KI Dupuis H Letzel S 《Disability and rehabilitation》2008,30(14):999-1013
Purpose. The influence of vibration-induced white finger disease on the quality of life and possible social consequences is the subject of the study presented herein. Method. The data acquisition was carried out by means of a standardized questionnaire. Parameters such as quality of life, professional practice, prevention and social security were assessed among other things. Results. Nearly three quarters of the interviewees (n = 115) did not consult a physician with the occurrence of the first complaints. Physicians frequently made the correct diagnosis only with delay. From the first occurrence of symptoms to the acknowledgment as an occupational disease 0.5 - 34.5 years had usually elapsed. The quality of life affected the patients and their families. Change of profession and unemployment were frequently associated with substantial problems. There is clear need for information regarding the clinical picture, protective possibilities in the workplace, recognition as an occupational disease and financial problems. The introduction of industrial safety measures was not substantially affected by the occurrence of the disease. Conclusions. A quick diagnosis and the recognition of this occupational disease are important in view of its potential reversibility upon discontinuation of the exposition to vibration. As a consequence, intensified preventive measures need to be called for. 相似文献
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L M Patrias A C Klaver M P Coffey D A Loeffler 《Clinical and experimental immunology》2010,161(3):527-535
Alpha‐synuclein is the major protein in Lewy bodies, the hallmark pathological finding in Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Although normally intracellular, it also can be secreted, so extracellular alpha‐synuclein may contribute to neuronal injury. Serum antibodies to alpha‐synuclein could exert protective effects by increasing alpha‐synuclein's movement out of the brain and, if they cross the blood–brain barrier, by inhibiting its neurotoxic effects. The objective of this study was to measure antibody concentrations to alpha‐synuclein monomer and soluble oligomers in three intravenous immunoglobulin (IVIG) preparations, Gamunex (Talecris Biotherapeutics), Gammagard (Baxter Healthcare) and Flebogamma (Grifols Biologicals). Antibodies were measured in native IVIG preparations and after antibody–antigen complex dissociation. IVIG's non‐specific binding was subtracted from its total binding to alpha‐synuclein to calculate specific anti‐alpha‐synuclein antibody concentrations. Specific antibodies to alpha‐synuclein monomer and/or soluble oligomers were detected in all IVIG products. In native IVIG preparations, the highest anti‐monomer concentrations were in Gammagard and the highest anti‐oligomer concentrations were in Gamunex; the extent to which lot‐to‐lot variation may have contributed to these differences was not determined. Antibody–antigen complex dissociation had variable effects on these antibody levels. The IVIG preparations did not inhibit alpha‐synuclein oligomer formation, although they changed the distribution and intensity of some oligomer bands on Western blots. The presence of antibodies to soluble alpha‐synuclein conformations in IVIG preparations suggests that their effects should be studied in animal models of synucleinopathies, as a first step to determine their feasibility as a possible treatment for PD and other synucleinopathies. 相似文献
145.
Alastair JS Webb Amy Lawson Linxin Li Sara Mazzucco Peter M Rothwell for the Oxford Vascular Study Phenotyped Cohort 《Journal of cerebral blood flow and metabolism》2021,41(6):1463
Cerebral arterial pulsatility is strongly associated with cerebral small vessel disease and lacunar stroke yet its dependence on central versus local haemodynamic processes is unclear. In a population-based study of patients on best medical managment, 4–6 weeks after a TIA or non-disabling stroke, arterial stiffness and aortic systolic, diastolic and pulse pressures were measured (Sphygmocor). Middle cerebral artery peak and trough flow velocities and Gosling’s pulsatility index were measured by transcranial ultrasound. In 981 participants, aortic and cerebral pulsatility rose strongly with age in both sexes, but aortic diastolic pressure fell more with age in men whilst cerebral trough velocity fell more in women. There was no significant association between aortic systolic or diastolic blood pressure with cerebral peak or trough flow velocity but aortic pulse pressure explained 37% of the variance in cerebral arterial pulsatility, before adjustment, whilst 49% of the variance was explained by aortic pulse pressure, arterial stiffness, age, gender and cardiovascular risk factors. Furthermore, arterial stiffness partially mediated the relationship between aortic and cerebral pulsatility. Overall, absolute aortic pressures and cerebral blood flow velocity were poorly correlated but aortic and cerebral pulsatility were strongly related, suggesting a key role for transmission of aortic pulsatility to the brain. 相似文献
146.
147.
Nigel W Crawford Anthony G Catto-Smith Mark R Oliver Donald JS Cameron Jim P Buttery 《BMC gastroenterology》2011,11(1):1-8
Background
Pre-existing polyps, especially large polyps, are known to be the major source for colorectal cancer, but there is limited available information about factors that are associated with polyp size and polyp growth. We aim to determine factors associated with polyp size in different age groups.Methods
Colonoscopy data were prospectively collected from 67 adult gastrointestinal practice sites in the United States between 2002 and 2007 using a computer-generated endoscopic report form. Data were transmitted to and stored in a central data repository, where all asymptomatic white (n = 78352) and black (n = 4289) patients who had a polyp finding on screening colonoscopy were identified. Univariate and multivariate analysis of age, gender, performance site, race, polyp location, number of polyps, and family history as risk factors associated with the size of the largest polyp detected at colonoscopy.Results
In both genders, size of the largest polyp increased progressively with age in all age groups (P < .0001). In subjects ≥ 80 years the relative risk was 1.55 (95% CI, 1.35-1.79) compared to subjects in the youngest age group. With the exception of family history, all study variables were significantly associated with polyp size (P < .0001), with multiple polyps (≥ 2 versus 1) having the strongest risk: 3.41 (95% CI, 3.29-3.54).Conclusions
In both genders there is a significant increase in polyp size detected during screening colonoscopy with increasing age. Important additional risk factors associated with increasing polyp size are gender, race, polyp location, and number of polyps, with polyp multiplicity being the strongest risk factor. Previous family history of bowel cancer was not a risk factor. 相似文献148.
149.
Helen E. Gruber PhD Gretchen Hoelscher MS Bryan Loeffler MD Yin Chow BS Jane A. Ingram BS Will Halligan BS Edward N. Hanley Jr. MD 《The spine journal》2009,9(9):760-766
Background contextEpidermal growth factor (EGF) is a peptide known to modulate a number of cellular responses including embryogenesis, cell proliferation, and cell survival. Little is known about EGF and its regulation in human annulus cells. Previous work has identified EGF and its receptor in control outer annulus disc tissue, but not in herniated tissue.PurposeTo determine if human annulus cells express EGF in vitro, to determine if the epidermal growth factor-receptor (EGF-r) was expressed in vivo and in vitro in disc cells, to test the effect of EGF on annulus cell proliferation and proteoglycan production in vitro, and to test the effect of prostaglandin E1 (PGE1) and misoprostol on disc cell production of EGF in vitro.Study design/settingStudies were approved by the authors' Human Subjects Institutional review Board. Human disc tissue was used for immunocytochemistry, and human annulus cells were tested in vitro.Patient sampleThirty-four disc specimens were used for studies of proteoglycan production, cell proliferation, and EGF production in vitro. An additional nine discs were used for EGF-r immunolocalization.MethodsDisc tissue was used for immunocytochemical studies for the localization of EGF-r and as a source for cultured annulus cells. Monolayer culture was used to test proliferation responses to 0, 25, 50, or 75 ng/mL EGF over a 2-day culture period. Three-dimensional (3D) culture in a collagen sponge was used to test 100,000 cells cultured in a paired experimental design over 14 days for production of EGF and proteoglycans. Cells were exposed to control conditions, or to either misoprostol at 8 ng/mL or PGE1 at 10?7 M. Conditioned media was harvested and assayed using an enzyme-linked immunosorbent assay (ELISA) assay with the Human Protein Cytokine Antibody Array I kit. Replicate EGF relative intensity values were averaged and normalized to controls assayed on the same membrane. 3D-cultured cells were also used to confirm EGF gene expression using microarray analysis. Standard statistical methods were used to analyze results.ResultsMicroarray analysis of mRNA from annulus cells in 3D culture confirmed expression of EGF, and immunocytochemistry verified the presence of EGF-r in vitro and in vivo. PGE1, at a dose of 10?7 M, and misoprostol (a synthetic PGE1 analog) at a dose of 8 ng/mL, both significantly increased EGF levels in annulus cells cultured in 3D compared with control levels (p=.031 and .034, respectively). No significant difference, however, was seen in cell proliferation or in total sulfated proteoglycan production in EGF-exposed annulus cells.ConclusionsData showed that EGF is expressed and produced by annulus cells in vivo and in 3D culture, with significantly greater in vitro EGF produced in the presence of PGE1 or the PGE1 analog misoprostol. Misoprostol, developed for prevention/treatment of nonsteroidal anti-inflammatory-induced gastropathy, has now been reported to have some interesting anabolic effects stimulating osteoblasts during fracture healing and during ovariectomy in animal models. Exogenous EGF did not increase cell proliferation in monolayer, or total production of proteoglycans in 3D culture. Additional work is needed to further delineate the role of EGF in the human disc. 相似文献
150.