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Possible Causal Relationship (possible + causal_relationship)
Selected AbstractsAnalytical ecological epidemiology: exposure,response relations in spatially stratified time seriesENVIRONMETRICS, Issue 6 2009Hagen Scherb Abstract An important task of environmental research is the investigation of a possible causal relationship between exposure and the frequency of a biologic trait. Major industrial accidents provide examples where the exposure status of large populations may change considerably within relatively short time intervals of days or weeks (e.g. Seveso herbicide plant explosion, Chernobyl Nuclear Power Plant catastrophe). Therefore, purely temporal change-points may be tested in time series of appropriate public health indicators (e.g. mortality, morbidity, sex ratio at birth). If, in addition, the spatial contamination is strong and variable enough and can be identified with sufficient precision at the level of regional units (e.g. districts), then a spatial-temporal approach makes sense. This essentially means that a global time trend model is adjusted for region-specific trend functions, allowing for local or global temporal jumps or broken sticks (change-points) at certain points in time. The local jump heights may be tested for associations with local exposure (exposure,response relation), and all other characteristics in the data that vary with locality and in time are automatically accounted for, thus minimizing confounding. Spatial-temporal approaches may help to strengthen the evidence of possible causal relationships. As an example, the human sex ratio at birth in several European countries before and after the Chernobyl Nuclear Power Plant accident was investigated. A long-term chronic impact of radioactive fallout on the secondary sex ratio has been found. Copyright © 2008 John Wiley & Sons, Ltd. [source] Compound odontoma associated with an unerupted and dilacerated maxillary primary central incisor in a young patientINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 3 2003K. H. Yeung Summary., The occurrence of odontoma in the primary dentition is uncommon. There are very few reports of non-eruption of a dilacerated primary tooth in the literature. A rare case of compound odontoma in association with an unerupted dilacerated maxillary primary incisor in a young patient is reported. There was also a developing supernumerary tooth in the vicinity of the odontoma. The clinical features and management of these conditions are discussed. The relevant literature is reviewed. A possible causal relationship between odontoma and dilaceration is highlighted. [source] Epithelioid sarcoma with angiomatoid features: report of an unusual case arising in an elderly patient within a burn scarJOURNAL OF CUTANEOUS PATHOLOGY, Issue 3 2008Steven Kaddu Epithelioid sarcoma (ES) is a rare, aggressive soft tissue tumor with a characteristic predilection for adolescents and young adults, and a tendency to occur on distal extremities. We report a case of ES arising in an 80-year-old woman within a burn scar that histopathologically showed unusual ,angiomatoid' features. The patient presented initially with a solitary nodule on her right wrist arising at the site of a burn scar. Histopathologically, the tumor was composed of a proliferation of relatively bland, epithelioid and spindle cells focally arranged in a nodular pattern around areas of ,geographic' necrosis. In addition, there were prominent foci of hemorrhage and blood-filled spaces as well as tumor cells with intracytoplasmic vacuoles, features suggestive of an angiomatous process. Immunohistochemistry showed positivity of tumor cells for cytokeratins and epithelial membrane antigen (EMA) whereas all vascular markers tested were negative. The overall histopathologic features were consistent with a diagnosis of ES. Follow up showed multiple recurrences arising proximally along the right upper extremity. Our case underlines the clinical and histopathological heterogeneity of ES, emphasizing the unusual occurrence of ES with ,angiomatoid' features in the elderly. In this uncommon setting, this tumor should be especially distinguished from epithelioid hemangioendothelioma and epithelioid angiosarcoma. The significance of development of ES on a healed burn scar is uncertain, but may suggest a possible causal relationship. [source] Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trialJOURNAL OF INTERNAL MEDICINE, Issue 6 2008R. Jorde Abstract. Objectives., The objective of the present study was to examine the cross-sectional relation between serum 25-hydoxyvitamin D [25-(OH) D] levels and depression in overweight and obese subjects and to assess the effect of vitamin D supplementation on depressive symptoms. Design., Cross-sectional study and randomized double blind controlled trial of 20.000 or 40.000 IU vitamin D per week versus placebo for 1 year. Setting., A total of 441 subjects (body mass index 28,47 kg m,2, 159 men and 282 women, aged 21,70 years) recruited by advertisements or from the out-patient clinic at the University Hospital of North Norway. Main outcome measures., Beck Depression Inventory (BDI) score with subscales 1,13 and 14,21. Results., Subjects with serum 25(OH)D levels <40 nmol L,1 scored significantly higher (more depressive traits) than those with serum 25(OH)D levels ,40 nmol L,1 on the BDI total [6.0 (0,23) versus 4.5 (0,28) (median and range)] and the BDI subscale 1,13 [2.0 (0,15) versus 1.0 (0,29.5)] (P < 0.05). In the two groups given vitamin D, but not in the placebo group, there was a significant improvement in BDI scores after 1 year. There was a significant decrease in serum parathyroid hormone in the two vitamin D groups without a concomitant increase in serum calcium. Conclusions., It appears to be a relation between serum levels of 25(OH)D and symptoms of depression. Supplementation with high doses of vitamin D seems to ameliorate these symptoms indicating a possible causal relationship. [source] Safety update on the possible causal relationship between gadolinium-containing MRI agents and nephrogenic systemic fibrosisJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2007Michael Pedersen PhD [source] Effect of L -arginine supplementation on immune responsiveness in patients with sickle cell disease,PEDIATRIC BLOOD & CANCER, Issue 2 2010Arnette Scavella MD Abstract Background L -arginine (L -Arg) is deficient in sickle cell disease (SSD) during vasoocclusion. We investigated possible causal relationship between L -Arg deficiency and immune dysfunction in SSD in steady-state. Procedure Fifteen patients with SSD in steady-state and 13 controls were studied. Plasma L -Arg levels were measured using liquid chromatography. T cell subsets and CD3zeta (CD3,) chain expression were analyzed using flow cytometry. Lymphocyte proliferative response to phytohemagglutinin (PHA) and production of IL-6 and interferon-gamma (IFN-,) were evaluated with and without L -Arg. Results SSD patients had significantly lower L -Arg levels than controls. CD3 and CD19 cell populations were comparable for both groups, but SSD patients had above normal numbers of natural killer cells (P,=,0.06). Patients and controls exhibited significantly increased lymphocyte blastogenesis to PHA after introduction of L -Arg to cultures; response of patients was significantly greater than values for control individuals. Proliferative response to candida in SSD patients was significantly lower than in controls; L -Arg supplementation did not increase this response. L -Arg had no effect on blastogenic response to PPD and candida albicans. No effect was likewise seen in production of IL-6 and IFN-, after addition of L -Arg. CD3, chain expression increased after addition of L -Arg in both groups; differences were insignificant. Conclusion L -Arg levels in steady-state SSD are significantly lower than in controls. L -Arg supplementation enhanced lymphocyte blastogenesis to PHA for both controls and patients, but not in response to antigen. There were no significant differences in CD3, chain expression although upregulation of expression occurred after L -Arg supplementation for both groups. Pediatr Blood Cancer. 2010;55:318,323. © 2010 Wiley,Liss, Inc. [source] Markers of oxidative and nitrosative stress in systemic lupus erythematosus: Correlation with disease activity,ARTHRITIS & RHEUMATISM, Issue 7 2010Gangduo Wang Objective Free radical,mediated reactions have been implicated as contributors in a number of autoimmune diseases, including systemic lupus erythematosus (SLE). However, the potential for oxidative/nitrosative stress to elicit an autoimmune response or to contribute to disease pathogenesis, and thus be useful when determining a prognosis, remains largely unexplored in humans. This study was undertaken to investigate the status and contribution of oxidative/nitrosative stress in patients with SLE. Methods Sera from 72 SLE patients with varying levels of disease activity according to the SLE Disease Activity Index (SLEDAI) and 36 age- and sex-matched healthy controls were evaluated for serum levels of oxidative/nitrosative stress markers, including antibodies to malondialdehyde (anti-MDA) protein adducts and to 4-hydroxynonenal (anti-HNE) protein adducts, MDA/HNE protein adducts, superoxide dismutase (SOD), nitrotyrosine (NT), and inducible nitric oxide synthase (iNOS). Results Serum analysis showed significantly higher levels of both anti,MDA/anti,HNE protein adduct antibodies and MDA/HNE protein adducts in SLE patients compared with healthy controls. Interestingly, not only was there an increased number of subjects positive for anti-MDA or anti-HNE antibodies, but also the levels of both of these antibodies were statistically significantly higher among SLE patients whose SLEDAI scores were ,6 as compared with SLE patients with lower SLEDAI scores (SLEDAI score <6). In addition, a significant correlation was observed between the levels of anti-MDA or anti-HNE antibodies and the SLEDAI score (r = 0.734 and r = 0.647, respectively), suggesting a possible causal relationship between these antibodies and SLE. Furthermore, sera from SLE patients had lower levels of SOD and higher levels of iNOS and NT compared with healthy control sera. Conclusion These findings support an association between oxidative/nitrosative stress and SLE. The stronger response observed in serum samples from patients with higher SLEDAI scores suggests that markers of oxidative/nitrosative stress may be useful in evaluating the progression of SLE and in elucidating the mechanisms of disease pathogenesis. [source] Clindamycin and taste disordersBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 4 2007Mark C. H. De Groot What is already known about this subject. ,,The antibiotic clindamycin has a bitter taste when it is used orally. What this study adds ,,A case series on oral as well as i.v. use of clindamycin associated with taste disorders is presented. ,,After corrections in a case-by-case analysis for several possible confounders such as indication, clindamycin is disproportionally associated with taste disorders. ,,Serum and hence saliva and sputum clindamycin levels seem to be responsible for this reversible adverse drug reaction. Aims Topical use of clindamycin has been associated with taste disorders in the literature, but little is known about the nature of this adverse drug reaction. The aim of this article was to describe reports of clindamycin-induced taste disorders and to analyse the factors involved. Methods The adverse drug reaction database of the Netherlands Pharmacovigilance Centre was searched for reports concerning taste disorders with antibiotics. Clinical review of the cases and statistical analysis with logistic regression were performed. Characteristics of patients who reported taste disorders were compared for age, gender and formulation in clindamycin vs. other antibiotic users. Results Taste disorders were reported in seven (18%) of the clindamycin cases. In five reports an oral formulation was involved, in one report intravenous (i.v.) administration and in one report both formulations were used. Latency was <1 day after start and in one case taste disorders were present repeatedly at 10 min after every i.v. application. The adjusted reporting odds ratio was 7.0 (95% confidence interval 2.8, 17.3) and supports a possible causal relationship. Conclusions The association of clindamycin and taste disorders is supported by disproportionality analysis and seems to be independent of possible confounders such as age, gender and infections. The case reports suggest a role for clindamycin concentrations excreted in body fluids like saliva. [source] Glycodelin: a novel serum anti-inflammatory marker in type 1 diabetic retinopathy during pregnancyACTA OPHTHALMOLOGICA, Issue 1 2007Sirpa Loukovaara Abstract. Purpose:, Inflammation may play a role in the development of diabetic retinopathy during pregnancy. Glycodelin is a glycoprotein whose secretion from the endometrial glands increases during pregnancy. Glycodelin has immunosuppressive properties thought to play a role in the protection of the fetoplacental unit. We studied the role of glycodelin in the development and progression of retinopathy in type 1 diabetes during pregnancy. Methods:, Retinopathy was graded from fundus photographs in 45 diabetes subjects and nine non-diabetes subjects prospectively during pregnancy. Serum glycodelin concentration was measured by an immunofluorometric assay. Results:, In women with diabetes with progression of retinopathy, serum glycodelin concentration was 263 ng/ml (range 116,505 ng/ml) during the first trimester, 61 ng/ml (range 30,106 ng/ml) during the second trimester, and 29 ng/ml (range 13,53 ng/ml) during the third trimester, compared with values of 595 ng/ml (range 376,870 ng/ml), 104 ng/ml (range 75,228 ng/ml) and 45 ng/ml (range 32,74 ng/ml), respectively, in diabetes subjects without progression (p = 0.005 between the groups). Low glycodelin concentration was associated with progression of diabetic retinopathy in multiple regression analysis. Serum glycodelin concentration was similar in women with and without diabetes throughout pregnancy (p = 0.63 by repeated measures anova). Conclusions:, Low glycodelin concentration is associated with progression of retinopathy in pregnant women with diabetes. A possible causal relationship between low glycodelin levels and progression of retinopathy may be mediated by the immunomodulatory properties of glycodelin. [source] | ||||||||||