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991.
PURPOSE: To evaluate the safety of intravitreous ovine hyaluronidase for the management of vitreous hemorrhage. DESIGN: Two prospective, randomized, placebo-controlled, double-masked studies. Pooled efficacy data are presented in a companion article in this issue of The Journal. METHODS: Subjects with vitreous hemorrhage > or = 1 month, severe at entry and best corrected visual acuity (BCVA) worse than 20/200 in the study eye were randomized to 7.5 IU, 55 IU, 75 IU ovine hyaluronidase, saline, or no injection. Assessments occurred on day 1, week 1, months 1, 2, 3, 6, and then every 6 months for as long as 32 months. Assessments included history, ocular symptoms, adverse events, BCVA, intraocular pressure, external eye examination, slit-lamp biomicroscopy, fundus examination, B-scan ultrasonography, and fundus photography. RESULTS: Of 1362 subjects in the safety population, 1344 received hyaluronidase or saline and 18 no treatment. Iritis was the most common ocular adverse event, occurring in 33.3%, 62.1%, 58.9%, and 62.1% of saline, 7.5 IU, 55 IU, and 75 IU-treated subjects. In eyes with more than mild iritis, a dose response was observed: 8.9%, 20.2%, 33.7%, and 39.7% of saline, 7.5 IU, 55 IU, and 75 IU-treated subjects, respectively, were noted to have moderate or severe iritis. Retinal detachments (RDs) were reported in 9.5% of study eyes: 26 (6.9%), 22 (11.1%), 35 (9.3%), and 45 (11.5%) in the saline, 7.5 IU, 55 IU, and 75 IU-treated subjects. Overall, 1.8% of study eyes had rhegmatogenous RD: 1.1%, 2.5%, 1.6%, and 2.3% of saline, 7.5, 55, and 75 IU treated subjects. Cataracts occurred similarly across treatment groups. No injection-related infectious endophthalmitis was reported. CONCLUSIONS: No serious safety issues were reported after a single intravitreous injection of ovine hyaluronidase. RD incidence was not statistically different between groups. Iritis manifesting as an acute self limited inflammation was the most common adverse event, occurred in a dose response fashion, but was not noted to result in a serious adverse event in any hyaluronidase treated eye.  相似文献   
992.
PURPOSE: To purify and characterize the glycoprotein lumican, isolated from human amniotic membrane (AM), and to examine its efficacy in treating corneal epithelium debridement. METHODS: An affinity-purified, anti-human lumican antibody-conjugated protein A Sepharose column was used to purify soluble lumican protein from human AM. The purified AM lumican was characterized by two-dimensional and SDS gel electrophoresis, plus Western blot analysis with anti-lumican antibody. The effects of lumican on corneal epithelial wound healing were examined in an organ culture mouse eye model. RESULTS: Lumican was found to be abundantly present in the stroma of human AM. It was extracted from the AM by isotonic, 1 M NaCl, and 4 M guanidine HCl solutions, suggesting that it is present in both the soluble and matrix-bound states. In two-dimensional gel electrophoresis, the 50-kDa human amniotic lumican purified by antibody-conjugated affinity chromatography migrated in a smear between pH 3.0 and 6.0. After endo-beta-galactosidase digestion, it existed as a single core protein at pH 6.0, suggesting that native human amniotic lumican is a glycoprotein with short sugar moiety. Addition of purified human AM lumican to cultured medium promoted re-epithelialization and enhanced cell proliferation of wild-type mouse corneal epithelial cells in an organ culture. In lumican-knockout (lum(-/-)) mice, the effect of human lumican on promoting corneal epithelial wound healing was even more dramatic than in wild-type mice. CONCLUSIONS: The diversified functions of lumican include modulation of epithelial cells in wound healing and serving as an extracellular matrix component. Administration of lumican may be beneficial for treating epithelial defects in the cornea and other tissues.  相似文献   
993.
Chronic exposure to benzene has been shown to lead to bone marrow depression and the development of leukemia. The mechanism underlying the carcinogenicity of benzene is unknown, although a number of genetic changes including chromosomal aberrations have been associated with benzene toxicity. Metabolism of benzene is required for the induced toxicological effects. We have investigated the effect of trans,trans-muconaldehyde (MUC), hydroquinone (HQ), and four MUC metabolites on gap-junction intercellular communication (GJIC). Inhibition of GJIC has been considered a possible predictor of tumor promoters and non-genotoxic carcinogens, and shown to result in perturbation of hematopoiesis. MUC was found to be a strong inhibitor of GJIC (EC50=12 mol L–1) in rat liver epithelial cells IAR20, with potency similar to that of chlordane (EC50=7 mol L–1). HQ inhibited GJIC with an EC50 of 25 mol L–1, and the metabolite OH/CHO with an EC50 of 58 mol L–1. The other MUC metabolites tested, CHO/COOH and OH/COOH were weak inhibitors of GJIC whereas COOH/COOH had no effect. Benzene itself had no effect on GJIC when tested in concentrations up to 20 mmol L–1. The relative potency observed for the metabolites on GJIC is similar to their hematotoxic effects. The effect of MUC on GJIC was observed to take place concordant with a dramatic loss of connexin 43 (Cx43) from the cells as visualized by Western blotting. Substances with the ability to inhibit Cx43-dependent GJIC have previously been observed to interfere with normal hematopoietic development. The ability of benzene metabolites to interfere with gap-junction functionality, and especially the dramatic loss of Cx43 induced by MUC, should therefore be considered as a possible mechanism for benzene-induced hematotoxicity and development of leukemia.  相似文献   
994.
Objective: Pharmaceutical care follows a needs-based approach. Cancer patients form a group with particular needs. Information about cancer treatment plays an important role in terms of coping strategies, initiation of self-care behaviour, and quality of life. In order to develop pharmaceutical care strategies for cancer patients, it is important to assess patients information needs. This survey aims at providing a suitable instrument to measure patient satisfaction with information on cancer treatment and to reveal the present situation in Germany.Methods: Since there was no suitable German measure available, the Canadian Patient Satisfaction with Cancer Treatment Education (PS-CaTE) questionnaire was translated into German and its test quality criteria were examined. Selected socio-demographic variables were added to the original version of the questionnaire to facilitate subgroup analysis. A pre-test was performed to assess the reliability of the adapted instrument.The questionnaire was distributed among patients of cooperating hospitals, oncology practices, and self-aid groups over Germany.Results: The pre-test established a good reliability of the instrument. In the main survey, overall satisfaction, on a 5- point Likert scale, showed a median score of 3.5, where 5 represented the highest degree of satisfaction. A subscale analysis revealed that satisfaction with information provided on adverse events and complementary treatment options was lower compared to the information provided on cancer treatment. A stepwise multiple-regression analysis identified three significant predictors of satisfaction: a) diagnosis of a mammary carcinoma; b) recent diagnosis; and c) treatment by a primary-care oncologist. Patients with a mammary carcinoma and patients treated by a primary-care oncologist were less satisfied, and patients with a recent diagnosis were more satisfied compared to other patients. In comparison to other information sources, pharmacists still seem to play a minor role as a source of information for patients.Conclusions: The version of the questionnaire with a total of 14 items seems to be suitable for measuring patient satisfaction with information. Additional research is needed to further verify the validity of the instrument. The questionnaire may help pharmaceutical-care providers to develop needs-based information strategies. The assessment of patient satisfaction can contribute to the outcome evaluation of pharmaceutical care. The fact that pharmacists are not yet being recognised by most patients as a source of information should support an intensified and more active offer of care by the pharmacist.  相似文献   
995.
Expert consensus recommends liver biopsy before therapy for chronic hepatitis C. A cost effectiveness analysis suggested that the best strategy in the management of patients was to treat without biopsy. We compared therapy in patients who did, or did not undergo biopsy. Hepatitis C virus (HCV)-positive patients (78) who did not agree to (n = 57) or with contraindications to liver biopsy (n = 21) (group A) were matched for age, sex and genotype with those who consented (group B). Before therapy (interferon/ribavirin for 12 months), a clinical diagnosis of chronic hepatitis, on the basis of standard biochemical and ultrasonographic parameters. The two groups showed similar baseline characteristics. A noninvasive, diagnosis of chronic hepatitis was made in 75.6% of group A, and in 83.3% of group B (P = 0.26). Concordance between clinical and histological diagnosis in group B amounted to 91%. End-of-therapy virological response was 52.6% in group A, and 57.7% in group B (P = 0.63). Sustained virological response was 41.0% [95% confidence interval (CI) 30.1-51.9] and 43.6% (95% CI 32.6-54.6) in the two groups (P = 0.87). Predictors of sustained response were noninvasive diagnosis of chronic hepatitis (P = 0.006), lack of portal hypertension (P = 0.037), platelets >10(5)/mm3 (P = 0.007), prothrombin >70% (P = 0.02), and genotype 2 or 3 (P < 0.0001). At multivariate analysis, genotype (P < 0.0001) and platelets (P = 0.004) maintained their predictive power. In most patients with HCV infection, virological clearance after therapy can be achieved irrespective of whatever a liver biopsy might show.  相似文献   
996.
ABSTRACT: BACKGROUND: According to recent surveys, 59 % of British medical schools and 90 % of US medical schools have courses or content on spirituality and health (S/H). There is little research, however, on the teaching of S/H in medical schools in other countries, such as those in Latin America, Asia, Australia and Africa. The present study seeks to investigate the current status of teaching on S/H in Brazilian medical schools. METHODS: All medical schools in Brazil (private and public) were selected for evaluation, were contacted by email and phone, and were administered a questionnaire. The questionnaire, sent by e-mail, asked medical school directors/deans about any S/H courses that were taught, details about those courses, S/H lectures or seminars, importance of teaching this subject for medical school directors, and medical schools characteristics. RESULTS: A total of 86 out of 180 (47.7 %) medical schools responded. Results indicated that 10.4 % of Brazilian Medical Schools have a dedicated S/H courses and 40.5 % have courses or content on spirituality and health. Only two medical schools have S/H courses that involve hands-on training and three schools have S/H courses that teach how to conduct a spiritual history. The majority of medical directors (54 %) believe that S/H is important to teach in their schools. CONCLUSION: Few Brazilian medical schools have courses dealing specifically with S/H and less than half provide some form of teaching on the subject. Unfortunately, there is no standard curriculum on S/H. Nevertheless, the majority of medical directors believe this issue is an important subject that should be taught.  相似文献   
997.
The majority of patients infected with human T‐cell lymphotropic virus‐type 1 (HTLV‐1) are considered carriers, but a high frequency of urinary symptoms of overactive bladder, common in HTLV‐1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) have been documented in these patients. The aim of this study was to determine if immunological and viral factors that are seen in HAM/TSP are also observed in these patients. Participants were classified as HTLV‐1 carriers (n = 45), HTLV‐1 patients suffering from overactive bladder (n = 45) and HAM/TSP (n = 45). Cells from HTLV‐1 overactive bladder patients produced spontaneously more proinflammatory cytokines than carriers. TNF‐α and IL‐17 levels were similar in HAM/TSP and HTLV‐1 overactive bladder patients. High proviral load was found in patients with overactive bladder and HAM/TSP and correlated with proinflammatory cytokines. In contrast with findings in patients with HAM/TSP, serum levels of Th1 chemokines were similar in HTLV‐1 overactive bladder and carriers. Exogenous addition of regulatory cytokines decreased spontaneous IFN‐γ production in cell cultures from HTLV‐1 overactive bladder patients. The results show that HTLV‐1 overactive bladder and HAM/TSP patients have in common some immunological features as well as similar proviral load profile. The data show that HTLV‐1 overactive bladder patients are still able to down regulate their inflammatory immune response. In addition, these patients express levels of chemokines similar to carriers, which may explain why they have yet to develop the same degree of spinal cord damage as seen in patients with HAM/TSP. These patients present symptoms of overactive bladder, which may be an early sign of HAM/TSP. J. Med. Virol. 84:1809–1817, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
998.
In two siblings of consanguineous parents with intermittent nephrotic-range proteinuria, we identified a homozygous deleterious frameshift mutation in the gene CUBN, which encodes cubulin, using exome capture and massively parallel re-sequencing. The mutation segregated with affected members of this family and was absent from 92 healthy individuals, thereby identifying a recessive mutation in CUBN as the single-gene cause of proteinuria in this sibship. Cubulin mutations cause a hereditary form of megaloblastic anemia secondary to vitamin B(12) deficiency, and proteinuria occurs in 50% of cases since cubilin is coreceptor for both the intestinal vitamin B(12)-intrinsic factor complex and the tubular reabsorption of protein in the proximal tubule. In summary, we report successful use of exome capture and massively parallel re-sequencing to identify a rare, single-gene cause of nephropathy.  相似文献   
999.
The phenotype of germinal center (GC) B cells includes the unique ability to tolerate rapid proliferation and the mutagenic actions of activation induced cytosine deaminase (AICDA). Given the importance of epigenetic patterning in determining cellular phenotypes, we examined DNA methylation and the role of DNA methyltransferases in the formation of GCs. DNA methylation profiling revealed a marked shift in DNA methylation patterning in GC B cells versus resting/naive B cells. This shift included significant differential methylation of 235 genes, with concordant inverse changes in gene expression affecting most notably genes of the NFkB and MAP kinase signaling pathways. GC B cells were predominantly hypomethylated compared with naive B cells and AICDA binding sites were highly overrepresented among hypomethylated loci. GC B cells also exhibited greater DNA methylation heterogeneity than naive B cells. Among DNA methyltransferases (DNMTs), only DNMT1 was significantly up-regulated in GC B cells. Dnmt1 hypomorphic mice displayed deficient GC formation and treatment of mice with the DNA methyltransferase inhibitor decitabine resulted in failure to form GCs after immune stimulation. Notably, the GC B cells of Dnmt1 hypomorphic animals showed evidence of increased DNA damage, suggesting dual roles for DNMT1 in DNA methylation and double strand DNA break repair.  相似文献   
1000.
Pediatric immune thrombocytopenia (ITP) is usually self-limited. However, approximately 20% of children develop chronic ITP, which can be associated with significant morbidity because of long-term immunosuppression and splenectomy in refractory cases. To explore the molecular mechanism of chronic ITP compared with acute ITP, we studied 63 pediatric patients with ITP. Gene expression analysis of whole blood revealed distinct signatures for acute and chronic ITP. Oxidative stress-related pathways were among the most significant chronic ITP-associated pathways. Overexpression of VNN1, an oxidative stress sensor in epithelial cells, was most strongly associated with progression to chronic ITP. Studies of normal persons demonstrated VNN1 expression in a variety of blood cells. Exposure of blood mononuclear cells to oxidative stress inducers elicited dramatic up-regulation of VNN1 and down-regulation of PPARγ, indicating a role for VNN1 as a peripheral blood oxidative stress sensor. Assessment of redox state by tandem mass spectrometry demonstrated statistically significant lower glutathione ratios in patients with ITP versus healthy controls; lower glutathione ratios were also seen in untreated patients with ITP compared with recently treated patients. Our work demonstrates distinct patterns of gene expression in acute and chronic ITP and implicates oxidative stress pathways in the pathogenesis of chronic pediatric ITP.  相似文献   
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