188 research outputs found
INHERITED HEARING LOSS: FROM GENE VARIANTS TO MECHANISMS OF DISEASE
Nonsyndromic Sensorineural Hearing Loss (NSHL) is the most common sensory disorder worldwide, affecting at least 1 in 500 newborns and more than half individuals older than 80 years. It is estimated that about 60-70% of cases are due to genetic factors [Raviv et al., 2010]. More than 70 genes have been associated with NSHL so far, but many others are still to be discovered. In this thesis, we investigated the genetic and molecular bases of NSHL by a double approach, consisting in: a) investigating the pathogenic mechanisms of mutations within the MIR96 gene, and b) searching for new genes/mutations by Whole-Exome Sequencing (WES) in selected NSHL families.
As far as MIR96 is concerned, we identified and characterized a novel mutation (the third described) within the MIR96 gene, miR-96 (+57T>C), in an Italian family with autosomal dominant NSHL. MiR-96 is part of the conserved miR-183 microRNA (miRNA) family, which plays essential functions in the vertebrate inner ear. Point mutations within the seed region of miR-96 (miR-96-5p) cause autosomal dominant NSHL (AD-NSHL). The novel identified mutation replaces a highly conserved nucleotide and is predicted to reduce the stability of the pre-miRNA hairpin. Ex vivo assays in mammalian cells confirmed that both miR-96 and miR-96*(miR-96-3p) mature species were significantly reduced in the mutant, whereas the precursor level was unaffected. Moreover, miR-96 and miR-96* expression could be restored to normal levels by reconstituting the secondary structure of the pre-miR-96 hairpin, thus demonstrating that the mutation hinders the precursor processing. Finally, even though the mature miR-96 sequence is not altered, we demonstrated that the identified mutation significantly impacts on miR-96 regulation of selected targets. Taken together, these data provide further evidence of the involvement of miR-96 in human deafness and demonstrate that a quantitative defect of this miRNA may contribute to NSHL.
As far as WES is concerned, the application of NGS to the identification of novel genes/mutations in 6 genetically undiagnosed Italian families (NSHL1-4 and 6, 7), with recessive NSHL and at least two affected individuals, has enabled the molecular diagnosis in two families (NSHL4 and NSHL6), and highlighted a putative novel deafness-associated gene in another family (NSHL3). In particular, a novel missense mutation within the PRPS1 gene was found in family NSHL4 and functionally characterized, together with other two mutations identified by candidate-gene screening in a larger X-linked NSHL cohort. In the NSHL3 family, WES pointed out a novel missense variant in DIAPH2, a gene not directly linked to NSHL but belonging to a family of proteins already involved in hearing loss. Studies aimed at the functional characterization of this mutation and at the clarification of the possible involvement of the gene in the pathogenesis of the disease are now being performed.
For the other three families (NSHL1, 2 and NSHL7), the search for pathogenic variations is still ongoing
Many analysts, one data set: making transparent how variations in analytic choices affect results
Twenty-nine teams involving 61 analysts used the same data set to address the same research question: whether soccer referees are more likely to give red cards to dark-skin-toned players than to light-skin-toned players. Analytic approaches varied widely across the teams, and the estimated effect sizes ranged from 0.89 to 2.93 (Mdn = 1.31) in odds-ratio units. Twenty teams (69%) found a statistically significant positive effect, and 9 teams (31%) did not observe a significant relationship. Overall, the 29 different analyses used 21 unique combinations of covariates. Neither analysts’ prior beliefs about the effect of interest nor their level of expertise readily explained the variation in the outcomes of the analyses. Peer ratings of the quality of the analyses also did not account for the variability. These findings suggest that significant variation in the results of analyses of complex data may be difficult to avoid, even by experts with honest intentions. Crowdsourcing data analysis, a strategy in which numerous research teams are recruited to simultaneously investigate the same research question, makes transparent how defensible, yet subjective, analytic choices influence research results
Self-Study In Patient Safety And Quality Improvement To Enhance Student Experience In Interprofessional Case Competition
Objective: The Interprofessional Student Advisory Team (IPSAT) at the University of New England (UNE) organized its 2nd interprofessional student case competition, modeled after the CLARION competition from the University of Minnesota. Completion of an online certificate in patient safety and quality improvement from the Institute for Healthcare Improvement (IHI) Open School was added as a pre-requisite to participation in the 2014 competition. Completion of this program was predicted to improve student preparedness and confidence and facilitate interprofessional teamwork during their case preparation.
Conclusions: Survey results indicate an increase in student confidence and preparedness for interprofessional teamwork during the 2014 UNE IPSAT case competition. Survey research was limited by a small number of completed surveys, a delay in IRB approval and unfamiliarity with the IRB suggested survey software. IPSAT student leaders at UNE will continue to require completion of the IHI Open School Basic Certificate as a prerequisite for enrollment in future IPSAT case competitions.https://dune.une.edu/minigrant_ipsat2014/1000/thumbnail.jp
BUILDING BRIDGES FOR INNOVATION IN AGEING : SYNERGIES BETWEEN ACTION GROUPS OF THE EIP ON AHA
The Strategic Implementation Plan of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) proposed six Action Groups. After almost three years of activity, many achievements have been obtained through commitments or collaborative work of the Action Groups. However, they have often worked in silos and, consequently, synergies between Action Groups have been proposed to strengthen the triple win of the EIP on AHA. The paper presents the methodology and current status of the Task Force on EIP on AHA synergies. Synergies are in line with the Action Groups' new Renovated Action Plan (2016-2018) to ensure that their future objectives are coherent and fully connected. The outcomes and impact of synergies are using the Monitoring and Assessment Framework for the EIP on AHA (MAFEIP). Eight proposals for synergies have been approved by the Task Force: Five cross-cutting synergies which can be used for all current and future synergies as they consider overarching domains (appropriate polypharmacy, citizen empowerment, teaching and coaching on AHA, deployment of synergies to EU regions, Responsible Research and Innovation), and three cross-cutting synergies focussing on current Action Group activities (falls, frailty, integrated care and chronic respiratory diseases).Peer reviewe
X-Linked Alport Syndrome in Women : Genotype and Clinical Course in 24 Cases
Objectives: X-linked Alport syndrome (XLAS) females are at risk of developing proteinuria and chronic kidney damage (CKD). The aim of this study is to evaluate the genotype-phenotype correlation in this rare population. Materials and Methods: This is a prospective, observational study of XLAS females, confirmed by a pathogenic mutation in COL4A5 and renal ultrastructural evaluation. Proteinuria, renal function and extrarenal involvement were monitored during follow-up. Patients were divided in 2 groups, according to mutations in COL4A5: missense (Group 1) and non-missense variants (Group 2). Results: Twenty-four XLAS females, aged 10.6 ± 10.4 years at clinical onset (mean follow-up: 13.1 ± 12.6 years) were recruited between 2000 and 2017 at a single center. In group 1 there were 10 patients and in group 2, 14 (mean age at the end of follow-up: 24.9 ± 13.6 and 23.2 ± 13.8 years, respectively). One patient in Group 1 and 9 in Group 2 (p = 0.013) developed proteinuria during follow-up. Mean eGFR at last follow-up was lower in Group 2 (p = 0.027), where two patients developed CKD. No differences in hearing loss were documented among the two groups. Two patients in Group 2 carried one mutation in both COL4A5 and COL4A3 (digenic inheritance) and were proteinuric. In one family, the mother presented only hematuria while the daughter was proteinuric and presented a greater inactivation of the X chromosome carrying the wild-type allele. Conclusions: The appearance of proteinuria and CKD is more frequent in patients with severe variants. Carrying digenic inheritance and skewed XCI seem to be additional risk factors for proteinuria in XLAS females
SLC22A4 Gene in Hereditary Non-syndromic Hearing Loss: Recurrence and Incomplete Penetrance of the p.C113Y Mutation in Northwest Africa
Inherited hearing loss is extremely heterogeneous both clinically and genetically. In addition, the spectrum of deafness-causing genetic variants differs greatly among geographical areas and ethnicities. The identification of the causal mutation in affected families allows early diagnosis, clinical follow-up, and genetic counseling. A large consanguineous family of Moroccan origin affected by autosomal recessive sensorineural hearing loss (ARSNHL) was subjected to genome-wide linkage analysis and exome sequencing. Exome-wide variant analysis and prioritization identified the SLC22A4 p.C113Y missense variant (rs768484124) as the most likely cause of ARSNHL in the family, falling within the unique significant (LOD score>3) linkage region on chromosome 5. Indeed, the same variant was previously reported in two Tunisian ARSNHL pedigrees. The variant is present in the homozygous state in all six affected individuals, but also in one normal-hearing sibling, suggesting incomplete penetrance. The mutation is absent in about 1,000 individuals from the Greater Middle East Variome
study cohort, including individuals from the North African population, as well as in an additional seven deaf patients from the same geographical area, recruited and screened for mutations in the SLC22A4 gene. This study represents the first independent replication of the involvement of SLC22A4 in ARSNHL, highlighting the importance of the gene, and of the p.C113Y mutation, at least in the Northwest African population
Non-medical risk factors as avoidable determinants of excess mortality in children with chronic kidney disease. A prospective cohort study in Nicaragua, a model low income country
Background: The widely recognized clinical and epidemiological relevance of the socioeconomic determinants of health-disease conditions is expected to be specifically critical in terms of chronic diseases in fragile populations in low-income countries. However, in the literature, there is a substantial gap between the attention directed towards the medical components of these problems and the actual adoption of strategies aimed at providing solutions for the associated socioeconomic determinants, especially in pediatric populations. We report a prospective outcome study on the independent contribution and reciprocal interaction of the medical and socioeconomic factors to the hard end-point of mortality in a cohort of children with chronic kidney disease in Nicaragua. Methods and Findings: Every child (n = 309) diagnosed with chronic kidney disease (CKD) and referred to the tertiary unit of Pediatric Nephrology in Managua (Nicaragua) from a network of nine hospitals serving 80% of the country's pediatric population was registered between January 2005 and December 2013. The three main socioeconomic determinants evaluated were family income, living conditions and the family's level of education. Further potential determinants of the outcomes included duration of exposure to disease, CKD stage at the first visit as suggested by the KDOQI guidelines in children, the time it took the patients to reach the reference centre and rural or urban context of life. Well-defined and systematically collected medical and socioeconomic data were available for 257 children over a mean follow-up period of 2.5\ub12.5 years. Mortality and lost to follow-up were considered as outcome endpoints both independently and in combination, because of the inevitably progressive nature of the disease. A high proportion (55%) of children presented in the advanced stages of CKD (CKD stage IV and V) at the first visit. At the end of follow-up, 145 (57%) of the 257 cohort children were alive, 47 (18%) were lost to follow-up and 65 (25%) had died. Cox regression analysis showed an independent contribution to mortality of CKD stage at diagnosis and of level of education, with overlapping HR values (HR and 95%CI: 2.66; 1.93-3.66 and 2.72; 1.71-4.33, respectively). Conclusions: The unfavourable socioeconomic and cultural background of the pediatric study cohort and the severity of kidney damage at diagnosis were the key determinants of the clinical risk conditions at baseline and of the mortality outcome. Long-term structural interventions on such backgrounds must be adopted to assure effectiveness of medical care and to assure an earlier diagnosis of CKD in these patients. The translation-extension of our results is currently underway with an agenda which includes: 1) better integration of chronic pediatric conditions into primary care strategies to promote prevention and early timely referral; 2) the consideration of socioeconomic conditions as a mandatory component of the packages of best-care; 3) the formulation and flexible adaptation of guidelines and educational programs, based on the information generated by a context-specific, epidemiological monitoring of needs and outcomes, guaranteed by an effective database
Fatigue response of additively manufactured Maraging Stainless Steel CX and effects of heat treatment and surface finishing
This paper deals with the novel topic of the fatigue response of additively manufactured Maraging Stainless Steel CX. A two-by-two factorial plan was arranged, to experimentally assess the effects of heat treatment and machining on the fatigue strength in both finite and infinite life domains. The two factors were regarded as on–off, taking the untreated unmachined condition as a reference for comparisons. Cylindrical specimens with vertical build orientation were involved in the fatigue campaign under four-point rotating bending. The results indicate that the fatigue strength may be remarkably incremented (up to five times) with respect to the as received conditions, especially thanks to surface smoothing and taking advantage of a very low porosity level. Heat treatment strengthening mechanisms were also interpreted in the light of optical and electron microscope observations. Fatigue enhancement arises from precipitate size increment throughout the conducted heat treatment, although the fracture mode turns to be more brittle
Fatigue response of additively manufactured as-built 15-5 PH stainless steel and effects of machining and thermal and surface treatments
Additively produced 15-5 PH stainless steel has wide industrial applications, but the combined effects of heat treatment, machining, and shot-peening and their order have not been deeply investigated. This topic is addressed here by a 2-by-3 experimental plan that has involved S–N curve and fatigue limit determination, using vertically built cylindrical samples, tested under rotating bending. The obtained responses have been analyzed by an ANOVA-based statistical approach for comparison of fatigue trends. Results indicate that heat treatment without machining may be even detrimental for fatigue due to embrittlement. Conversely, machining with subsequent shot-peening, even without heat treatment, has a remarkable impact and leads to a doubled fatigue strength with respect to as-built material. This strength is also quite close to that achievable for wrought material. The study has been completed by micrography and fractography, to reveal the dependence of microstructure, crack initiation sites, and failure mode on the performed treatments
Lower risk of death and cardiovascular events in patients with diabetes initiating glucagon-like peptide-1 receptor agonists or sodium-glucose cotransporter-2 inhibitors: A real-world study in two Italian cohorts
Aim: To examine the efficacy and safety of glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter-2 (SGLT2) inhibitors compared with other antihyperglycaemic agents (AHAs) in large and unselected populations of the Lombardy and Apulia regions in Italy. Materials and Methods: An observational cohort study of first-time users of GLP-1RAs, SGLT2 inhibitors or other AHAs was conducted from 2010 to 2018. Death and cardiovascular (CV) events were evaluated using conditional Cox models in propensity-score-matched populations. Adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated for each region and in a meta-analysis for pooled risks. Results: After propensity-score matching, the Lombardy cohort included 18 716 and 11 683 patients and the Apulia cohort 9772 and 6046 patients for the GLP-1RA and SGLT2 inhibitor groups, respectively. Use of GLP-1RAs was associated with lower rates of death (HR 0.61, CI 0.56-0.65, Lombardy; HR 0.63, CI 0.55-0.71, Apulia), cerebrovascular disease and ischaemic stroke (HR 0.70, CI 0.63-0.79; HR 0.72, CI 0.60-0.87, Lombardy), peripheral vascular disease (HR 0.72, CI 0.64-0.82, Lombardy; HR 0.80, CI 0.67-0.98, Apulia), and lower limb complications (HR 0.67, CI 0.56-0.81, Lombardy; HR 0.69, CI 0.51-0.93, Apulia). Compared with other AHAs, SGLT2 inhibitor use decreased the risk of death (HR 0.47, CI 0.40-0.54, Lombardy; HR 0.43, CI 0.32-0.57, Apulia), cerebrovascular disease (HR 0.75, CI 0.61-0.91, Lombardy; HR 0.72, CI 0.54-0.96, Apulia), and heart failure (HR 0.56, CI 0.46-0.70, Lombardy; HR 0.57, CI 0.42-0.77, Apulia). In the pooled cohorts, a reduction in heart failure was also observed with GLP-1RAs (HR 0.89, 95% CI 0.82-0.97). Serious adverse events were quite low in frequency. Conclusion: Our findings from real-world practice confirm the favourable effect of GLP-1RAs and SGLT2 inhibitors on death and CV outcomes across both regions consistently. Thus, these drug classes should be preferentially considered in a broad type 2 diabetes population beyond those with CV disease
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