225 resultados para Snails as carriers of disease
Resumo:
Smoking is a leading global cause of disease and mortality. We established the Oxford-GlaxoSmithKline study (Ox-GSK) to perform a genome-wide meta-analysis of SNP association with smoking-related behavioral traits. Our final data set included 41,150 individuals drawn from 20 disease, population and control cohorts. Our analysis confirmed an effect on smoking quantity at a locus on 15q25 (P = 9.45 x 10(-19)) that includes CHRNA5, CHRNA3 and CHRNB4, three genes encoding neuronal nicotinic acetylcholine receptor subunits. We used data from the 1000 Genomes project to investigate the region using imputation, which allowed for analysis of virtually all common SNPs in the region and offered a fivefold increase in marker density over HapMap2 (ref. 2) as an imputation reference panel. Our fine-mapping approach identified a SNP showing the highest significance, rs55853698, located within the promoter region of CHRNA5. Conditional analysis also identified a secondary locus (rs6495308) in CHRNA3.
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Chromosomes with Ag staining that varies from one metaphase to the other can be distinguished from those with an Ag-staining that is the same in all metaphases. The intercellular variation of an Ag-NOR can be attributed to many different factors. Whatever the importance of technical factors, they do not seem to account for the large variations in Ag-staining which were observed for each ac. This suggests the existence of a natural intercellular variability of the NOR's activity. The variation of the Ag-stainability of a given NOR, the diversity of Ag-stainings observed on the ten ac of one individual and the differences that exist between individuals raise the question of the existence of a compensation of activity between nucleolar organizers. The study, for each individual, of the mean sum of staining per metaphase reveals that this value is not absolutely constant from one individual to another; in the carriers of Robertsonian fusions it is smaller than in chromosomally normal individuals. The analysis of the transmission shows that inactive NORs remain inactive and that active NORs present a variation in the activity from one generation to the next.
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Studies aiming at the elucidation of the genetic basis of rare monogenic forms of hypertension have identified mutations in genes coding for the epithelial sodium channel ENaC, for the mineralocorticoid receptor, or for enzymes crucial for the synthesis of aldosterone. These genetic studies clearly demonstrate the importance of the regulation of Na(+) absorption in the aldosterone-sensitive distal nephron (ASDN), for the maintenance of the extracellular fluid volume and blood pressure. Recent studies aiming at a better understanding of the cellular and molecular basis of ENaC-mediated Na(+) absorption in the distal part of nephron, have essentially focused on the regulation ENaC activity and on the aldosterone-signaling cascade. ENaC is a constitutively open channel, and factors controlling the number of active channels at the cell surface are likely to have profound effects on Na(+) absorption in the ASDN, and in the amount of Na(+) that is excreted in the final urine. A number of membrane-bound proteases, kinases, have recently been identified that increase ENaC activity at the cell surface in heterologous expressions systems. Ubiquitylation is a general process that regulates the stability of a variety of target proteins that include ENaC. Recently, deubiquitylating enzymes have been shown to increase ENaC activity in heterologous expressions systems. These regulatory mechanisms are likely to be nephron specific, since in vivo studies indicate that the adaptation of the renal excretion of Na(+) in response to Na(+) diet occurs predominantly in the early part (the connecting tubule) of the ASDN. An important work is presently done to determine in vivo the physiological relevance of these cellular and molecular mechanisms in regulation of ENaC activity. The contribution of the protease-dependent ENaC regulation in mediating Na(+) absorption in the ASDN is still not clearly understood. The signaling pathway that involves ubiquitylation of ENaC does not seem to be absolutely required for the aldosterone-mediated control of ENaC. These in vivo physiological studies presently constitute a major challenge for our understanding of the regulation of ENaC to maintain the Na(+) balance.
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Endometriosis, a leading cause of pelvic pain and infertility, is characterized by ectopic growth of endometrial-like tissue and affects approximately 176 million women worldwide. The pathophysiology involves inflammatory and angiogenic mediators as well as estrogen-mediated signaling and novel, improved therapeutics targeting these pathways are necessary. The aim of this study was to investigate mechanisms leading to the establishment and progression of endometriosis as well as the effect of local treatment with Lipoxin A4 (LXA₄), an anti-inflammatory and pro-resolving lipid mediator that we have recently characterized as an estrogen receptor agonist. LXA₄ treatment significantly reduced endometriotic lesion size and downregulated the pro-inflammatory cytokines IL-1β and IL-6, as well as the angiogenic factor VEGF. LXA₄ also inhibited COX-2 expression in both endometriotic lesions and peritoneal fluid cells, resulting in attenuated peritoneal fluid Prostaglandin E₂ (PGE₂) levels. Besides its anti-inflammatory effects, LXA₄ differentially regulated the expression and activity of the matrix remodeling enzyme matrix metalloproteinase (MMP)-9 as well as modulating transforming growth factor (TGF)-β isoform expression within endometriotic lesions and in peritoneal fluid cells. We also report for first time that LXA₄ attenuated aromatase expression, estrogen signaling and estrogen-regulated genes implicated in cellular proliferation in a mouse model of disease. These effects were observed both when LXA₄ was administered prior to disease induction and during established disease. Collectively, our findings highlight potential targets for the treatment of endometriosis and suggest a pleotropic effect of LXA₄ on disease progression, by attenuating pro-inflammatory and angiogenic mediators, matrix remodeling enzymes, estrogen metabolism and signaling, as well as downstream proliferative pathways.
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Background: The desire to improve the quality of health care for an aging population with multiple chronic diseases is fostering a rapid growth in inter-professional team care, supported by health professionals, governments, businesses and public institutions. However, the weight of evidence measuring the impact of team care on patient and health system outcomes has not, heretofore, been clear. To address this deficiency, we evaluated published evidence for the clinical effectiveness of team care within a chronic disease management context in a systematic overview. Methods: A search strategy was built for Medline using medical subject headings and other relevant keywords. After testing for perform- ance, the search strategy was adapted to other databases (Cinhal, Cochrane, Embase, PsychInfo) using their specific descriptors. The searches were limited to reviews published between 1996 and 2011, in English and French languages. The results were analyzed by the number of studies favouring team intervention, based on the direction of effect and statistical significance for all reported outcomes. Results: Sixteen systematic and 7 narrative reviews were included. Diseases most frequently targeted were depression, followed by heart failure, diabetes and mental disorders. Effective- ness outcome measures most commonly used were clinical endpoints, resource utilization (e.g., emergency room visits, hospital admissions), costs, quality of life and medication adherence. Briefly, while improved clinical and resource utilization endpoints were commonly reported as positive outcomes, mixed directional results were often found among costs, medication adherence, mortality and patient satisfaction outcomes. Conclusions: We conclude that, although suggestive of some specific benefits, the overall weight of evidence for team care efficacy remains equivocal. Further studies that examine the causal interactions between multidisciplinary team care and clinical and economic outcomes of disease management are needed to more accurately assess its net program efficacy and population effectiveness.
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BACKGROUND: Inflammatory bowel disease (IBD) starting during childhood has been assumed to impair quality of life (QoL) of affected children. As this aspect is crucial for further personality development, the health-related quality of life (HRQOL) was assessed in a Swiss nationwide cohort to obtain detailed information on the fields of impairment. METHODS: Data were prospectively acquired from pediatric patients included in the Swiss IBD Cohort Study. IBD activity was evaluated by PCDAI and PUCAI. The age adapted KIDSCREEN questionnaire was evaluated for 110 children with IBD (64 with Crohn's disease 46 with ulcerative colitis). Data were analyzed with respect to established reference values of healthy controls. RESULTS: In the KIDSCREEN index a moderate impairment was only found for physical wellbeing due to disease activity. In contrast, mental well-being and social support were even better as compared to control values. A subgroup analysis revealed that this observation was restricted to the children in the German speaking part of Switzerland, whereas there was no difference compared to controls in the French part of Switzerland. Furthermore, autonomy and school variables were significantly higher in the IBD patients as compared to controls. CONCLUSIONS: The social support for children with IBD is excellent in this cohort. Only physical well-being was impaired due to disease activity, whereas all other KIDSCREEN parameters were better as compared to controls. This indicates that effective coping and support strategies may be able to compensate the burden of disease in pediatric IBD patients.
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Although the precise signaling mechanisms underlying the vulnerability of some sub-populations of motoneurons in ALS remain unclear, critical factors such as metallo-proteinase 9 expression, neuronal activity and endoplasmic reticulum stress have been shown to be involved. In the context of SOD1(G93A) ALS mouse model, we previously showed that a two-fold decrease in calreticulin (CRT) is occurring in the vulnerable fast motoneurons. Here, we asked to which extent the decrease in CRT levels was causative to muscle denervation and/or motoneuron degeneration. Toward this goal, a hemizygous deletion of the crt gene in SOD1(G93A) mice was generated since the complete ablation of crt is embryonic lethal. We observed that SOD1(G93A);crt(+/-) mice display increased and earlier muscle weakness and muscle denervation compared to SOD1(G93A) mice. While CRT reduction in motoneurons leads to a strong upregulation of two factors important in motoneuron dysfunction, ER stress and mTOR activation, it does not aggravate motoneuron death. Our results underline a prevalent role for CRT levels in the early phase of muscle denervation and support CRT regulation as a potential therapeutic approach.
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The laboratory tests currently available to the clinician for day-to-day management of HIV infection are generally limited to the measurement of the viral load and of the CD4 cell count. More recently, analysis of drug resistance and of plasma drug levels have been added to the monitoring armamentarium. There are, however, numerous other techniques currently available to researchers that may in the future be incorporated into clinical routine. These include the analysis of human and viral genetic determinants of disease evolution, detailed analyses of immune recovery and reserve, pharmacogenetic determinants of treatment response, and toxicity. These approaches may in the future provide highly individualized disease management.
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Infective endocarditis (IE) is lethal if not aggressively treated with antibiotics alone or in combination with surgery. The epidemiology of this condition has substantially changed over the past four decades, especially in industrialized countries. Once a disease that predominantly affected young adults with previously well-identified valve disease--mostly chronic rheumatic heart disease--IE now tends to affect older patients and new at-risk groups, including intravenous-drug users, patients with intracardiac devices, and patients exposed to healthcare-associated bacteremia. As a result, skin organisms (for example, Staphylococcus spp.) are now reported as the pathogen in these populations more often than oral streptococci, which still prevail in the community and in native-valve IE. Moreover, progress in molecular diagnostics has helped to improve the diagnosis of poorly cultivable pathogens, such as Bartonella spp. and Tropheryma whipplei, which are responsible for blood-culture-negative IE more often than expected. Epidemiological data indicate that IE mostly occurs independently of medico-surgical procedures, and that circumstantial antibiotic prophylaxis is likely to protect only a minute proportion of individuals at risk. Therefore, new strategies to prevent IE--including improvement of dental hygiene, decontamination of carriers of Staphylococcus aureus, vaccination, and, possibly, antiplatelet therapy--must be explored.
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The first gene profiling study of cancer-specific CD8+ T-cells demonstrates that lymphocyte dysfunction in cancer tissue is due to multiple molecular alterations,(1) similar as in "exhausted" T-cells in chronic infection.(2) The data suggest novel drug targets, and show that T-cell exhaustion is reversible and limited to anatomical sites of disease.
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Summary: Friedreich's ataxia (FRDA), the most common autosomal recessive ataxia, is characterised by progressive ataxia with dysarthria of speech, loss of deep-tendon reflexes, impaired vibratory and proprioceptive sensations and corticospinal weakness with a Babinski's sign. Patients eventually also develop kyphoscoliosis, cardiomyopathy and diabetes mellitus. The disease is a GAA repeat disorder resulting in severely reduced levels of frataxin, with secondary increased sensitivity to oxidative stress. The anti-oxidative drug, idebenone, is effective against FRDA-associated cardiomyopathy. We provide detailed clinical, electrophysiological and biochemical data from 20 genetically confirmed FRDA patients and have analysed the relation-ship between phenotype, genotype and malondialdehyde (MDA), which is a marker of superoxide formation. We assessed the effects of idebenone biochemically by measuring blood M DA and clinically by serial measurements of the International Cooperative Ataxia Rating Scale (ICARS). The GAA repeat length influenced the age at onset (p <0.001), the severity of ataxia (p= 0.02), the presence of cardiomyopathy (p =0.04) and of low-frequency hearing loss (p = 0.009). Multilinear regression analysis showed (p = 0.006) that ICARS was dependent on the two variables of disease duration (p = 0.01) and size of the GAA expansion (p = 0.02). We found no correlation to bilateral palpebral ptosis visual impairment, diabetes mellitus or skeletal deformities, all of which appear to be signs of disease progression rather than severity. We discuss more thoroughly two underrecognised clinical findings: palpebral ptosis and GAA length-dependent low-frequency hearing loss. The average ICARS remained unchanged in 10 patients for whom follow-up on treatment was available (mean 2.9 years), whereas most patients treated with idebenone reported an improvement in dysarthria (63%), hand dexterity (.58%) and fatigue (47%) after taking the drug for several weeks or months. Oxidative stress analysis showed an unexpected increase in blood MDA levels in patients on idebenone (p = 0.04), and we discuss the putative underlying mechanism for this result, which could then explain the unique efficacy of idebenone in treating the FRDA-associated cardiomyopathy, as opposed to other antioxidative drugs. Indeed, idebenone is not only a powerful stimulator of complexes II and III of the respiratory chain, but also an inhibitor of complex I activity, then promoting superoxide formation. Our preliminary clinical observations are the first to date supporting an effect of idebenone in delaying neurological worsening. Our MDA results point to the dual effect of idebenone on oxidative stress and to the need for controlled studies to assess its potential toxicity at high doses on the one hand, and to revisit the exact mechanisms underlying the .physiopathology of Friedreich's ataxia on the other hand, while recent reports suggest non-oxidative pathophysiology of the disease.
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Analyzing the type and frequency of patient-specific mutations that give rise to Duchenne muscular dystrophy (DMD) is an invaluable tool for diagnostics, basic scientific research, trial planning, and improved clinical care. Locus-specific databases allow for the collection, organization, storage, and analysis of genetic variants of disease. Here, we describe the development and analysis of the TREAT-NMD DMD Global database (http://umd.be/TREAT_DMD/). We analyzed genetic data for 7,149 DMD mutations held within the database. A total of 5,682 large mutations were observed (80% of total mutations), of which 4,894 (86%) were deletions (1 exon or larger) and 784 (14%) were duplications (1 exon or larger). There were 1,445 small mutations (smaller than 1 exon, 20% of all mutations), of which 358 (25%) were small deletions and 132 (9%) small insertions and 199 (14%) affected the splice sites. Point mutations totalled 756 (52% of small mutations) with 726 (50%) nonsense mutations and 30 (2%) missense mutations. Finally, 22 (0.3%) mid-intronic mutations were observed. In addition, mutations were identified within the database that would potentially benefit from novel genetic therapies for DMD including stop codon read-through therapies (10% of total mutations) and exon skipping therapy (80% of deletions and 55% of total mutations).
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OBJECTIVE: To compare outcomes of patients with lymph node (LN)-positive urothelial carcinoma of the bladder (UCB) treated with or without cisplatin-based combined adjuvant chemotherapy (AC) after radical cystectomy (RC). PATIENTS AND METHODS: We retrospectively analysed 1523 patients with LN-positive UCB, who underwent RC with bilateral pelvic LN dissection. All patients had no evidence of disease after RC. AC was administered within 3 months. Competing-risks models were applied to compare UCB-related mortality. RESULTS: Of the 1523 patients, 874 (57.4%) received AC. The cumulative 1-, 2- and 5-year UCB-related mortality rates for all patients were 16%, 36% and 56%, respectively. Administration of AC was associated with an 18% relative reduction in the risk of UCB-related death (subhazard ratio 0.82, P = 0.005). The absolute reduction in mortality was 3.5% at 5 years. The positive effect of AC was detectable in patients aged ≤70 years, in women, in pT3-4 disease, and in those with a higher LN density and lymphovascular invasion. This study is limited by its retrospective and non-randomised design, selection bias, the absence of central pathological review and lack in standardisation of LN dissection and cisplatin-based protocols. CONCLUSION: AC seems to reduce UCB-related mortality in patients with LN-positive UCB after RC. Younger patients, women and those with high-risk features such as pT3-4 disease, a higher LN density and lymphovascular invasion appear to benefit most. Appropriately powered prospective randomised trials are necessary to confirm these findings.
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Solitary fibrous tumors are rare neoplasms of mesenchymal origin that have been reported in various other extrathoracic sites, including the liver. We present a case series of three malignant solitary fibrous tumors of the liver, occurring in two women 74 and 80 years old and one 65-year-old man. No clinical features were predictive of malignancy except the large sizes and synchronous presence of lung metastases in two of the three cases. Histological examinations revealed the presence of high pleomorphic cellularity with nuclear atypia, necrosis and high mitotic ratios. All patients died of disease progression.
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IMPORTANCE: The association of copy number variations (CNVs), differing numbers of copies of genetic sequence at locations in the genome, with phenotypes such as intellectual disability has been almost exclusively evaluated using clinically ascertained cohorts. The contribution of these genetic variants to cognitive phenotypes in the general population remains unclear. OBJECTIVE: To investigate the clinical features conferred by CNVs associated with known syndromes in adult carriers without clinical preselection and to assess the genome-wide consequences of rare CNVs (frequency ≤0.05%; size ≥250 kilobase pairs [kb]) on carriers' educational attainment and intellectual disability prevalence in the general population. DESIGN, SETTING, AND PARTICIPANTS: The population biobank of Estonia contains 52,000 participants enrolled from 2002 through 2010. General practitioners examined participants and filled out a questionnaire of health- and lifestyle-related questions, as well as reported diagnoses. Copy number variant analysis was conducted on a random sample of 7877 individuals and genotype-phenotype associations with education and disease traits were evaluated. Our results were replicated on a high-functioning group of 993 Estonians and 3 geographically distinct populations in the United Kingdom, the United States, and Italy. MAIN OUTCOMES AND MEASURES: Phenotypes of genomic disorders in the general population, prevalence of autosomal CNVs, and association of these variants with educational attainment (from less than primary school through scientific degree) and prevalence of intellectual disability. RESULTS: Of the 7877 in the Estonian cohort, we identified 56 carriers of CNVs associated with known syndromes. Their phenotypes, including cognitive and psychiatric problems, epilepsy, neuropathies, obesity, and congenital malformations are similar to those described for carriers of identical rearrangements ascertained in clinical cohorts. A genome-wide evaluation of rare autosomal CNVs (frequency, ≤0.05%; ≥250 kb) identified 831 carriers (10.5%) of the screened general population. Eleven of 216 (5.1%) carriers of a deletion of at least 250 kb (odds ratio [OR], 3.16; 95% CI, 1.51-5.98; P = 1.5e-03) and 6 of 102 (5.9%) carriers of a duplication of at least 1 Mb (OR, 3.67; 95% CI, 1.29-8.54; P = .008) had an intellectual disability compared with 114 of 6819 (1.7%) in the Estonian cohort. The mean education attainment was 3.81 (P = 1.06e-04) among 248 (≥250 kb) deletion carriers and 3.69 (P = 5.024e-05) among 115 duplication carriers (≥1 Mb). Of the deletion carriers, 33.5% did not graduate from high school (OR, 1.48; 95% CI, 1.12-1.95; P = .005) and 39.1% of duplication carriers did not graduate high school (OR, 1.89; 95% CI, 1.27-2.8; P = 1.6e-03). Evidence for an association between rare CNVs and lower educational attainment was supported by analyses of cohorts of adults from Italy and the United States and adolescents from the United Kingdom. CONCLUSIONS AND RELEVANCE: Known pathogenic CNVs in unselected, but assumed to be healthy, adult populations may be associated with unrecognized clinical sequelae. Additionally, individually rare but collectively common intermediate-size CNVs may be negatively associated with educational attainment. Replication of these findings in additional population groups is warranted given the potential implications of this observation for genomics research, clinical care, and public health.