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81.
Background: Benefit assessment of drugs and medical products has become a legally established feature of medical research. A standardized assessment of benefits using scientifically sound and valid methods is essential. Objective: Development, validation and practical evaluation of an instrument to record patient benefit in treatment of acne. Patients and Methods: In open interviews with n = 50 patients, possible benefits of the therapy from the patients' point of view were recorded. The item pool thus generated was reviewed by a panel of dermatologists, psychologists and patients and transferred to a 23‐item questionnaire. This is used prior to therapy to assess patients' desired benefits and after therapy to record the perceived benefits. The therapy goals and the resulting benefits are then used to generate a weighted ‘Patient Benefit Index’ (PBI). The procedure has been tested for its validity and feasibility in n = 923 patients with acne. Results: Patients accepted the instrument and deemed it to be easily understandable. Additionally, the method proved itself to be internally consistent, constructively valid and sensitive to changes. Conclusions: The Patient Benefit Index (PBI) is a valid and highly accepted practical instrument for recording patient benefit. The PBI permits an individualized, patient‐weighted assessment of the benefits of acne therapy.  相似文献   
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To assess the immune recognition of DNA in systemic lupus erythematosus, the antigenic specificity of monoclonal anti-DNA antibodies from autoimmune MRL-lpr/lpr mice was investigated Determinant specificity was assessed by ELISA in terms of binding to a panel of ssDNA antigens including calf thymus, human placenta, Escherichia coli, Clostridium perfringens, Micrococcus lysodeikticus, salmon testes, chicken blood and murine DNA. Among the monoclonal antibodies, a variety of binding patterns was observed, although for all antibodies tested murine DNA was among the most reactive antigens. Binding to other DNAs varied markedly, with some antibodies showing only low reactivity to certain antigens in the test panel. Similar results were obtained with sera of individual MRL-lpr/lpr mice. These results suggest that anti-DNA antibodies bind specific antigenic determinants variably expressed by DNAs of various species. Furthermore, the preferential binding to mouse DNA by some MRL-lpr/lpr antibodies may suggest a role of self-DNA in the in vivo selection of anti-DNA antibodies for expression.  相似文献   
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BACKGROUND: Genetic influences have been shown to play a major role in determining the risk of attention-deficit hyperactivity disorder (ADHD). In addition, prenatal exposure to nicotine and/or alcohol has also been suggested to increase risk of the disorder. Little attention, however, has been directed to investigating the roles of genetic transmission and prenatal exposure simultaneously. METHOD: Diagnostic telephone interview data from parents of Missouri adolescent female twin pairs born during 1975-1985 were analyzed. Logistic regression models were fitted to interview data from a total of 1936 twin pairs (1091 MZ and 845 DZ pairs) to determine the relative contributions of parental smoking and drinking behavior (both during and outside of pregnancy) as risk factors for DSM-IV ADHD. Structural equation models were fitted to determine the extent of residual genetic and environmental influences on ADHD risk while controlling for effects of prenatal and parental predictors on risk. RESULTS: ADHD was more likely to be diagnosed in girls whose mothers or fathers were alcohol dependent, whose mothers reported heavy alcohol use during pregnancy, and in those with low birth weight. Controlling for other risk factors, risk was not significantly increased in those whose mothers smoked during pregnancy. After allowing for effects of prenatal and childhood predictors, 86% of the residual variance in ADHD risk was attributable to genetic effects and 14% to non-shared environmental influences. CONCLUSIONS: Prenatal and parental risk factors may not be important mediators of influences on risk with much of the association between these variables and ADHD appearing to be indirect.  相似文献   
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Summary We have produced a method to estimate ictal localized epileptic activity hidden among the background in scalp EEGs. When the visually completely different waveforms of the epileptic and background activities are nearly orthogonal, epileptic activity may be approximately extracted from the EEG data matrix by singular value decomposition with subsequent orthogonal rotation to match the distribution of one component with that of the epileptic source. A simulation study was carried out using a matrix mimicking the scalp EEG with an inconspicuous ictal epileptic activity from a dipole source. This hidden epileptic activity was approximately recovered by matching the dipole of interest with the epileptic dipole, even when the simulated waveforms of the epileptic and background activities were not exactly orthogonal. High linear correlation between these two types of waveforms hampered the recovery of the epileptic activity. In another simulation study employing two epileptic dipoles producing activities with the same waveform and a brief time lag, it was indicated that the temporal relationship between the epileptic activities could be also estimated using the cross-correlation function. In the preliminary clinical application of this method to the ictal EEGs of complex partial seizures, rhythmic activities with seemingly epileptic waveforms were estimated at the dipoles which were located in the vicinity of cortical lesions revealed by neuroimaging studies. These activities were indicated to appear before any change in the scalp EEG. We hope for the clinical application of this method for noninvasive estimation of inconspicuous ictal epileptic activity.The authors thank Prof. Peter K.H. Wong of the Department of Paediatrics, University of British Columbia, Canada, and Prof. Yutaka Tanaka and Mr. Kim Hyun Bin of the Department of Environmental and Mathematical Sciences, Faculty of Environmental Science and Technology, Okayama University, Japan, for their technical suggestions. This study was aided by a grant from the Japan Epilepsy Research Foundation.  相似文献   
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Diabetic nephropathy is one of the most common causes of end-stage renal failure, but the factors responsible for the development of diabetic nephropathy have not been fully elucidated. We examined the effect of deletion of the angiotensin-convert-ing enzyme 2 (Ace2) gene on diabetic kidney injury. Ace2(-/-) mice were crossed with Akita mice (Ins2(WT/C96Y)), a model of type 1 diabetes mellitus, and four groups of mice were studied at 3 months of age: Ace2(+/y)Ins2(WT/WT), Ace2(-/y)Ins2(WT/WT), Ace2(+/y) Ins2(WT/C96Y), and Ace2(-/y)Ins2(WT/C96Y). Ace2(-/y) Ins2(WT/C96Y) mice exhibited a twofold increase in the urinary albumin excretion rate compared with Ace2(+/y)Ins2(WT/C96Y) mice despite similar blood glucose levels. Ace2(-/y)Ins2(WT/C96Y) mice were the only group to exhibit increased mesangial matrix scores and glomerular basement membrane thicknesses compared with Ace2(+/y)Ins2(WT/WT) mice, accompanied by increased fibronectin and alpha-smooth muscle actin immunostaining in the glomeruli of Ace2(-/y) Ins2(WT/C96Y) mice. There were no differences in blood pressure or heart function to account for the exacerbation of kidney injury. Although kidney levels of angiotensin (Ang) II were not increased in the diabetic mice, treatment with an Ang II receptor blocker reduced urinary albumin excretion rate in Ace2(-/y)Ins2(WT/C96Y) mice, suggesting that acceleration of kidney injury in these mice is Ang II-mediated. We conclude that ACE2 plays a protective role in the diabetic kidney, and ACE2 is an important determinant of diabetic nephropathy.  相似文献   
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Large electronic databases of health care information, such as administrative claims and electronic health records, are available and are being used in a number of public health settings, including drug safety surveillance. However, because of a lack of standardization, clinical terminologies may differ across databases. With the aid of existing resources and expert coders, we have developed mapping tables to convert ICD-9-CM diagnosis codes used in some existing databases to SNOMED-CT and MedDRA. In addition, previously developed definitions for specific health outcomes of interest were mapped to the same standardized vocabularies. We evaluated how vocabulary mapping affected (1) the retention of clinical data from two test databases, (2) the semantic space of outcome definitions, (3) the prevalence of each outcome in the test databases, and (4) the reliability of analytic methods designed to detect drug-outcome associations in the test databases. Although vocabulary mapping affected the semantic space of some outcome definitions, as well as the prevalence of some outcomes in the test databases, it had only minor effects on the analysis of drug-outcome associations. Furthermore, both SNOMED-CT and MedDRA were viable for use as standardized vocabularies in systems designed to perform active medical product surveillance using disparate sources of observational data.  相似文献   
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For best hearing sensation, electrodes of auditory prosthesis must have an optimal electrical contact to the respective neuronal cells. To improve the electrode-nerve interface, microstructuring of implant surfaces could guide neuronal cells toward the electrode contact. To this end, femtosecond laser ablation was used to generate linear microgrooves on the two currently relevant cochlear implant materials, silicone elastomer and platinum. Silicone surfaces were structured by two different methods, either directly, by laser ablation or indirectly, by imprinting using laser-microstructured molds. The influence of surface structuring on neurite outgrowth was investigated utilizing a neuronal-like cell line and primary auditory neurons. The pheochromocytoma cell line PC-12 and primary spiral ganglion cells were cultured on microstructured auditory implant materials. The orientation of neurite outgrowth relative to the microgrooves was determined. Both cell types showed a preferred orientation in parallel to the microstructures on both, platinum and on molded silicone elastomer. Interestingly, microstructures generated by direct laser ablation of silicone did not influence the orientation of either cell type. This shows that differences in the manufacturing procedures can affect the ability of microstructured implant surfaces to guide the growth of neurites. This is of particular importance for clinical applications, since the molding technique represents a reproducible, economic, and commercially feasible manufacturing procedure for the microstructured silicone surfaces of medical implants.  相似文献   
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