915 resultados para Causal relationship
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We report a family with malignant sympathetic paragangliomas (PGL) exhibiting a new type of germline mutation in the succinate dehydrogenase subunit B (SDHB) gene. Two affected brothers, presenting with symptoms at the ages of 25 and 52 yr, suffered from malignant abdominal extraadrenal sympathetic PGL. They died of their disease at ages 43 and 61 yr. Their mother had the same history of signs and symptoms, suggesting a catecholamine-producing tumor at the age of 55 yr. Analysis of the germline DNA from these three patients revealed a novel mutation in exon 4 (H132P) of the SDHB gene. This mutation was absent in 160 control chromosomes. Loss of heterozygosity analysis of the tumors showed a loss of one SDHB allele, and RT-PCR-based expression analysis confirmed the exclusive expression of the mutated allele in both tumors. A review of the published PGL families revealed malignant tumors in seven of 12 well-documented families with SDHB mutation-associated extraadrenal PGL. These findings, as well as findings of the family reported here, suggest a strong causal relationship of SDHB germline mutations with malignant extraadrenal abdominal PGL and imply the necessity of a close follow-up of affected individuals and family members.
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The effect of cyclosporine A during the development phase of adjuvant arthritis was studied in 40 female rats. Five groups of eight animals each received oral cyclosporine, 2.5, 5, 10, 20, or 30 mg/kg daily for 30 days. Also, eight normal and eight diseased rats served as placebo controls. At the time of inoculation of the adjuvant suspension on day 0, measurement of disease parameters (paw swelling and vertebral density) was started concomitantly with beginning of therapy. On completion of the study, the animals were killed, and after measurement of total skeletal and segmental (hind legs and caudal spine plus two caudal vertebrae) calcium, the two assessed vertebrae and both femoral condyles were removed for histomorphometric evaluation (vertebrae) and for estimation of glycosaminoglycan (GAG) content of cartilage. Blood for osteocalcin determinations also was taken at term from control and untreated arthritic rats and from animals that had received 10 mg/kg cyclosporine. Treatment with 2.5 mg/kg was ineffective, but doses between 5 and 20 mg/kg prevented the development of articular and osseous lesions. The 20 mg/kg dose showed no better effect than 10 mg/kg. This was shown by the absence of inflammation and the presence of normal condylar GAG and total mineral content in the areas screened. Untreated animals showed marked reductions in all of these parameters. The 30 mg/kg dose was effective in blocking the GAG loss, but significant reductions in bone density and trabecular volume were seen. There was a close correlation between GAG and bone density values, suggesting a common causal relationship. Circulating osteocalcin was significantly elevated in the untreated animals with adjuvant arthritis.(ABSTRACT TRUNCATED AT 250 WORDS)
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The understanding of lumbar spine pathologies made substantial progress at the turn of the twentieth century. The authors review the original publication of Otto Veraguth in 1929 reporting on the successful resection of a herniated lumbar disc, published exclusively in the German language. His early report is put into the historical context, and its impact on the understanding of pathologies of the intervertebral disc (IVD) is estimated. The Swiss surgeon and Nobel Prize laureate Emil Theodor Kocher was among the first physicians to describe the traumatic rupture of the IVD in 1896. As early as 1909 Oppenheim and Krause published 2 case reports on surgery for a herniated lumbar disc. Goldthwait was the first physician to delineate the etiopathogenes is between annulus rupture, symptoms of sciatica, and neurological signs in his publication of 1911. Further publications by Middleton and Teacher in 1911 and Schmorl in 1929 added to the understanding of lumbar spinal pathologies. In 1929, the Swiss neurologist Veraguth (surgery performed by Hans Brun) and the American neurosurgeon Walter Edward Dandy both published their early experiences with the surgical therapy of a herniated lumbar disc. Veraguth's contribution, however, has not been appreciated internationally to date. The causal relationship between lumbar disc pathology and sciatica remained uncertain for some years to come. The causal relationship was not confirmed until Mixter and Barr's landmark paper in 1934 describing the association of sciatica and lumbar disc herniation, after which the surgical treatment became increasingly popular. Veraguth was among the first physicians to report on the clinical course of a patient with successful resection of a herniated lumbar disc. His observations should be acknowledged in view of the limited experience and literature on this ailment at that time.
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A successful career in football is the result of the appropriate interaction between different aspects of an individual’s life, since the various areas and phases of one’s life depend on each other. An endogenous causal relationship exists throughout a person’s entire history (Mayer, 1990). In particular, their family, work and sports career must be tuned to each other. The transition from the initial stages of education (compulsory schooling) to vocational training, which coincides with the beginning of the selection for the national youth teams, is a particularly critical phase (Wylleman, Theeboom, & Lavallee, 2004). In order to do justice to the overall life situation of a young sports talent during this transition phase, we have adopted a holistic perspective and follow Bergman, Magnusson and El-Khouri (2003) in using a person-oriented and systemic approach. In doing so, our main focus lies on the person-environment system. This overall system is made up of various subsystems, consisting of several operating factors which interact with one another. The different levels to which these operating factors are expressed lead to observable patterns, which can be summarised in the form of types. Particularly promising types can therefore be identified and the developmental process can be described. Former players on the Swiss U16 to U21 national football teams, born between 1981 and 1987 (n=159), were interviewed concerning their careers, and the operating factors school/vocational training, family support and sports environment were examined. With the help of the LICUR method (Linking of Clusters after removal of Residue) (Bergman et al., 2003), developmental types were identified which were promising in terms of achieving top performance in adulthood. A range of developmental types and anti-types emerge for the transition from the under-15 phase to the over-16 phase. One particularly promising type is observed in the over-16 phase, for which the operating factors education, family support and participation in national U16 to U18 teams have slightly above-average scores, with scores that are well above average in the sports environment.
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INTRODUCTION Herbal and dietary supplements are widely used as measures to improve and preserve health and well-being. Among the bestselling preparations are dietary supplement containing glucosamine and chondroitine sulfate taken to improve symptoms of osteoarthritis. METHODS AND RESULTS We here present a case of a male patient with biopsy-proven acute and severe autoimmune hepatitis subsequent to intake of a preparation containing glucosamine and chondroitine sulfate. Response to steroids was favorable and resulted in complete remission of the patient. Diagnostic work-up of the case revealed no other possible cause of liver injury, and causality assessment using the Roussel Uclaf Causality Assessment Method (RUCAM) resulted in a possible causal relationship between intake of glucosamine and chondroitine sulfate and the adverse hepatic reaction. CONCLUSION The present case recalls that products containing glucosamine and chondroitine sulfate can occasionally cause acute liver injury mimicking autoimmune hepatitis, and reminds of the potential dangers of compounds with poor efficacy and ill-defined safety records.
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Resting endothelial cells express the small proteoglycan biglycan, whereas sprouting endothelial cells also synthesize decorin, a related proteoglycan. Here we show that decorin is expressed in endothelial cells in human granulomatous tissue. For in vitro investigations, the human endothelium-derived cell line, EA.hy 926, was cultured for 6 or more days in the presence of 1% fetal calf serum on top of or within floating collagen lattices which were also populated by a small number of rat fibroblasts. Endothelial cells aligned in cord-like structures and developed cavities that were surrounded by human decorin. About 14% and 20% of endothelial cells became apoptotic after 6 and 12 days of co-culture, respectively. In the absence of fibroblasts, however, the extent of apoptosis was about 60% after 12 days, and cord-like structures were not formed nor could decorin production be induced. This was also the case when lattices populated by EA.hy 926 cells were maintained under one of the following conditions: 1) 10% fetal calf serum; 2) fibroblast-conditioned media; 3) exogenous decorin; or 4) treatment with individual growth factors known to be involved in angiogenesis. The mechanism(s) by which fibroblasts induce an angiogenic phenotype in EA.hy 926 cells is (are) not known, but a causal relationship between decorin expression and endothelial cell phenotype was suggested by transducing human decorin cDNA into EA.hy 926 cells using a replication-deficient adenovirus. When the transduced cells were cultured in collagen lattices, there was no requirement of fibroblasts for the formation of capillary-like structures and apoptosis was reduced. Thus, decorin expression seems to be of special importance for the survival of EA.hy 926 cells as well as for cord and tube formation in this angiogenesis model.
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Low-frequency "off-line" repetitive transcranial magnetic stimulation (rTMS) over the course of several minutes has attained considerable attention as a research tool in cognitive neuroscience due to its ability to induce functional disruptions of brain areas. This disruptive rTMS effect is highly valuable for revealing a causal relationship between brain and behavior. However, its influence on remote interconnected areas and, more importantly, the duration of the induced neurophysiological effects, remain unknown. These aspects are critical for a study design in the context of cognitive neuroscience. In order to investigate these issues, 12 healthy male subjects underwent 8 H(2)(15)O positron emission tomography (PET) scans after application of long-train low-frequency rTMS to the right dorsolateral prefrontal cortex (DLPFC). Immediately after the stimulation train, regional cerebral blood flow (rCBF) increases were present under the stimulation site as well as in other prefrontal cortical areas, including the ventrolateral prefrontal cortex (VLPFC) ipsilateral to the stimulation site. The mean increases in rCBF returned to baseline within 9 min. The duration of this unilateral prefrontal rTMS effect on rCBF is of particular interest to those who aim to influence behavior in cognitive paradigms that use an "off-line" approach.
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OBJECTIVES The purpose of this study was to investigate the survival effects of inferior vena cava filters in patients with venous thromboembolism (VTE) who had a significant bleeding risk. BACKGROUND The effectiveness of inferior vena cava filter use among patients with acute symptomatic VTE and known significant bleeding risk remains unclear. METHODS In this prospective cohort study of patients with acute VTE identified from the RIETE (Computerized Registry of Patients With Venous Thromboembolism), we assessed the association between inferior vena cava filter insertion for known significant bleeding risk and the outcomes of all-cause mortality, pulmonary embolism (PE)-related mortality, and VTE rates through 30 days after the initiation of VTE treatment. Propensity score matching was used to adjust for the likelihood of receiving a filter. RESULTS Of the 40,142 eligible patients who had acute symptomatic VTE, 371 underwent filter placement because of known significant bleeding risk. A total of 344 patients treated with a filter were matched with 344 patients treated without a filter. Propensity score-matched pairs showed a nonsignificant trend toward lower risk of all-cause death for filter insertion compared with no insertion (6.6% vs. 10.2%; p = 0.12). The risk-adjusted PE-related mortality rate was lower for filter insertion than no insertion (1.7% vs. 4.9%; p = 0.03). Risk-adjusted recurrent VTE rates were higher for filter insertion than for no insertion (6.1% vs. 0.6%; p < 0.001). CONCLUSIONS In patients presenting with VTE and with a significant bleeding risk, inferior vena cava filter insertion compared with anticoagulant therapy was associated with a lower risk of PE-related death and a higher risk of recurrent VTE. However, study design limitations do not imply a causal relationship between filter insertion and outcome.
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Hepatitis C virus (HCV) infections are the major cause of chronic liver disease, cirrhosis and hepatocellular carcinoma worldwide. Both spontaneous and treatment-induced clearance of HCV depend on genetic variation within the interferon-lambda locus, but until now no clear causal relationship has been established. Here we demonstrate that an amino-acid substitution in the IFNλ4 protein changing a proline at position 70 to a serine (P70S) substantially alters its antiviral activity. Patients harbouring the impaired IFNλ4-S70 variant display lower interferon-stimulated gene (ISG) expression levels, better treatment response rates and better spontaneous clearance rates, compared with patients coding for the fully active IFNλ4-P70 variant. Altogether, these data provide evidence supporting a role for the active IFNλ4 protein as the driver of high hepatic ISG expression as well as the cause of poor HCV clearance.
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The present dissertation focuses on trust and comprises three empirical essays on the concept itself and its foundations. All three essays investigate trust as an expectation and rely on selfreport measures of trust. Whereas the first two chapters investigate social trust, the third chapter investigates political trust. Essentially, there are three related important debates to which the following chapters contribute. A first debate discusses problems with current selfreport measures. Scholars recently started to question whether standard trust questions really measure the same across countries and languages. Chapter 1 engages in this debate. Using data from Switzerland it studies whether different trust questions measure the same latent trust constructs across individuals belonging to three different culturallinguistic regions. The second debate concerns the socalled forms or dimensions of trust. Recently, scholars started investigating whether trust is a onedimensional construct, i.e. whether an individual's trust judgment differs for categories of trustees such as strangers, neighbors, family members and friends or not. Relying on confirmatory factor analysis Chapter 2 investigates whether individuals really do make a difference between different trustee categories and to what extent these judgments can be summarized into higherorder latent trust constructs. The third debate is concerned with causes of differences in trust across humans. Chapter 3 focuses on the role of laterlife experiences, more precisely victimization experiences and investigates their causal relationship with generalized social trust. Chapter 4 focuses on the impact of direct democratic institutions on the trust relationship between citizens and political authorities.
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OBJECTIVE The role of hypertension and its impact on outcome in patients with acute coronary syndrome (ACS) is still debated. This study aimed to compare the outcomes of hypertensive and nonhypertensive ACS patients. METHODS Using data of ACS patients enrolled in the Acute Myocardial Infarction in Switzerland Plus Registry from 1997 to 2013, characteristics at presentation and outcomes in hospital and after 1 year were analyzed. Hypertension was defined as previously diagnosed and treated by a physician. The primary endpoint was mortality. Data were analyzed using multiple logistic regressions. RESULTS Among 41 771 ACS patients, 16 855 (40.4%) were without and 24 916 (59.6%) with preexisting hypertension. Patients with preexisting hypertension had a more favorable in-hospital outcome [odds ratio (OR) in-hospital mortality 0.82, 95% confidence interval (CI) 0.73-0.93; P = 0.022]. The independent predictors of in-hospital mortality for patients with preexisting hypertension were age, Killip class greater than 2, Charlson Comorbidity Index greater than 1, no pretreatment with statins and lower admission systemic blood pressure. Preexisting hypertension was not an independent predictor of 1-year mortality in the subgroup of patients (n = 7801) followed: OR 1.07, 95% CI 0.78-1.47; P = 0.68. Independent predictors of mortality 1 year after discharge for the 4796 patients with preexisting hypertension were age, male sex and comorbidities. Angiotensin-converting enzyme inhibitors or angiotensin II receptor antagonists and statins prescribed at discharge improved the outcomes. CONCLUSION Outcome of ACS patients with preexisting hypertension was associated with an improved in-hospital prognosis after adjustment for their higher baseline risk. However, this effect was not long-lasting and does not necessarily mean a causal relationship exists. Short-term and long-term management of patients with hypertension admitted with ACS could be further improved.
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RATIONALE Changes in the pulmonary microbiota are associated with progressive respiratory diseases including chronic obstructive pulmonary disease. Whether there is a causal relationship between these changes and disease progression remains unknown. OBJECTIVE To investigate the link between an altered microbiota and disease, we utilized a model of chronic lung inflammation in specific pathogen free (SPF) mice and mice depleted of microbiota by antibiotic treatment or devoid of a microbiota (axenic). METHODS Mice were challenged with LPS/elastase intranasally over 4 weeks, resulting in a chronically inflamed and damaged lung. The ensuing cellular infiltration, histological damage and decline in lung function were quantified. MEASUREMENTS AND MAIN RESULTS Similar to human disease, the composition of the pulmonary microbiota was altered in disease animals. We found that the microbiota richness and diversity were decreased in LPS/Elastase-treated mice, with an increased representation of the genera Pseudomonas, Lactobacillus and a reduction in Prevotella. Moreover, the microbiota was implicated in disease development as mice depleted of microbiota exhibited an improvement in lung function, reduction in airway inflammation, decrease in lymphoid neogenesis and auto-reactive antibody responses. The absence of microbial cues also markedly decreased the production of IL-17A, whilst intranasal transfer of fluid enriched with the pulmonary microbiota isolated from diseased mice enhanced IL-17A production in the lungs of antibiotic treated or axenic recipients. Finally, in mice harboring a microbiota, neutralizing IL-17A dampened inflammation and restored lung function. CONCLUSIONS Collectively, our data indicate that host-microbial cross-talk promotes inflammation and could underlie the chronicity of inflammatory lung diseases.
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Despite gains made by Title IX in the past 36 years, including increased female participation in high school and collegiate sport, there is evidence that gender equity in sport is not fully achieved. Researchers target the media because they tend to shape social values and disseminate information to the masses (Kane, 1978, in Fink & Kensicki, 2002). As sports become more pervasive, framing theory has become particularly relevant. The purpose of this study is to build on the Hardin et al. (2002) study by examining the relationship among media sports coverage, gender equity in sport and the perceptions young sports fans begin to form about gender and sport based on media consumption. The researcher hypothesized that since women face discrimination in sport starting from the time that they choose to participate, children will perceive male athletes and their sports as more legitimate. Additionally, the media play a major role in shaping the views of audiences, so the way that they represent male and female athletes, including juxtaposing them, may have an impact on children. The researcher conducted a content analysis of 24 Sports Illustrated for Kids issues from 1996 to 1999 and 24 issues from 2006 to 2007. The researcher analyzed the content of photographs (N=3219) and of headlines (N=762) by using the definitions determined by Hardin et al. (2002). We found that there is a disproportionate amount of coverage devoted to male athletes and that the discrepancy between media representation between men and women in sport has grown since the mid-1990s. This study also includes a focus group conducted with three children from a community swimming program in a northeastern town and found that those children were acutely aware of the differences between men and women in sport based on the discussion. The researcher does not attempt to find a causal relationship between these children’s perceptions and the way media represents them, but rather uses the focus group to complement the content analysis. As children become sports consumers in later life, future research exploring the relationship between children’s perceptions and the media’s representations need to be done before causality and the significance of media effects are determined.
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This study deals with the mineralogical variability of siliceous and zeolitic sediments, porcellanites, and cherts at small intervals in the continuously cored sequence of Deep Sea Drilling Project Site 462. Skeletal opal is preserved down to a maximum burial depth of 390 meters (middle Eocene). Below this level, the tests are totally dissolved or replaced and filled by opal-CT, quartz, clinoptilolite, and calcite. Etching of opaline tests does not increase continously with deeper burial. Opal solution accompanied by a conspicuous formation of authigenic clinoptilolite has a local maximum in Core 16 (150 m). A causal relationship with the lower Miocene hiatus at this level is highly probable. Oligocene to Cenomanian sediments represent an intermediate stage of silica diagenesis: the opal-CT/quartz ratios of the silicified rocks are frequently greater than 1, and quartz filling pores or replacing foraminifer tests is more widespread than quartz which converted from an opal-CT precursor. As at other sites, there is a marked discontinuity of the transitions from biogenic opal via opal-CT to quartz with increasing depth of burial. Layers with unaltered opal-A alternate with porcellanite beds; the intensity of the opal-CT-to-quartz transformation changes very rapidly from horizon to horizon and obviously is not correlated with lithologic parameters. The silica for authigenic clinoptilolite was derived from biogenic opal and decaying volcanic components.
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The benthic isotopic record of Miocene Cibicidoides from Site 709 provides a record of conditions in the Indian Ocean at a depth of about 3200 mbsf. As expected, the record qualitatively resembles those of other Deep Sea Drilling Project and Ocean Drilling Program sites. The data are consistent with the scenario for the evolution of thermohaline circulation in the Miocene Indian Ocean proposed by Woodruff and Savin (1989, doi:10.1029/PA004i001p00087). Further testing of that scenario, however, requires isotopic data for Cibicidoides from other Indian Ocean sites. There is a correlation between d13C values of Cibicidoides and planktonic:benthic (P:B)ratios of Site 709 sediments, implying a causal relationship between the corrosiveness of deep waters and concentration of CO2 derived from oxidation of organic matter.