Search results for "medicine.disease_cause"
showing 10 items of 6035 documents
DNA methylation changes and somatic mutations as tumorigenic events in Lynch syndrome-associated adenomas retaining mismatch repair protein expression
2018
Background: DNA mismatch repair (MMR) defects are a major factor in colorectal tumorigenesis in Lynch syndrome (LS) and 15% of sporadic cases. Some adenomas from carriers of inherited MMR gene mutations have intact MMR protein expression implying other mechanisms accelerating tumorigenesis. We determined roles of DNA methylation changes and somatic mutations in cancer-associated genes as tumorigenic events in LS-associated colorectal adenomas with intact MMR. Methods: We investigated 122 archival colorectal specimens of normal mucosae, adenomas and carcinomas from 57 LS patients. MMR-deficient (MMR-D, n 49) and MMR-proficient (MMR-P, n 18) adenomas were of particular interest and were inter…
Clinical severity and molecular characteristics of circulating and emerging rotaviruses in young children attending hospital emergency departments in…
2016
International audience; Group A rotavirus (RVA) is the leading cause of acute gastroenteritis in young children worldwide. A prospective surveillance network has been set up to investigate the virological and clinical features of RVA infections and to detect the emergence of potentially epidemic strains in France. From 2009 to 2014, RVA-positive stool samples were collected from 4800 children <5 years old attending the paediatric emergency units of 16 large hospitals. Rotaviruses were then genotyped by RT-PCR with regard to their outer capsid proteins VP4 and VP7. Genotyping of 4708 RVA showed that G1P[8] strains (62.2%) were predominant. The incidence of G9P[8] (11.5%), G3P[8] (10.4%) and …
Mutations in SKI in Shprintzen-Goldberg syndrome lead to attenuated TGF-β responses through SKI stabilization.
2020
ABSTRACTShprintzen-Goldberg syndrome (SGS) is a multisystemic connective tissue disorder, with considerable clinical overlap with Marfan and Loeys-Dietz syndromes. These syndromes have commonly been associated with enhanced TGF-β signaling. In SGS patients, heterozygous point mutations have been mapped to the transcriptional corepressor SKI, which is a negative regulator of TGF-β signaling that is rapidly degraded upon ligand stimulation. The molecular consequences of these mutations, however, are not understood. Here we use a combination of structural biology, genome editing and biochemistry to show that SGS mutations in SKI abolish its binding to phosphorylated SMAD2 and SMAD3. This resul…
Histo-blood group antigens in children with symptomatic rotavirus infection
2019
Group A rotaviruses are a major cause of acute gastroenteritis in children. The diversity and unequal geographical prevalence of rotavirus genotypes have been linked to histo-blood group antigens (HBGAs) in different human populations. In order to evaluate the role of HBGAs in rotavirus infections in our population, secretor status (FUT2+), ABO blood group, and Lewis antigens were determined in children attended for rotavirus gastroenteritis in Valencia, Spain. During three consecutive years (2013&ndash
Performance evaluation of gastrointestinal viral ELIte panel multiplex RT-PCR assay for the diagnosis of rotavirus, adenovirus and astrovirus infecti…
2019
Rotavirus, adenovirus, norovirus and astrovirus are considered to be among the major causes of sporadic cases and outbreaks of acute gastroenteritis globally. Rapid and accurate identification of enteric viruses is still a challenge for the clinical laboratory. Recently, several molecular platforms for the detection of viral enteric pathogens have become available. In this study, the diagnostic accuracy of InGenius Gastrointestinal Viral (GV) Elite Panel, a newly developed one-step multiplex real-time RT-PCR assay simultaneously detecting rotavirus, adenovirus and astrovirus, was evaluated retrospectively analyzing an archival collection of 128 stool samples of children hospitalized with ac…
Facial cutaneo-mucosal venous malformations can develop independently of mutation of TEK gene but may be associated with excessive expression of Src…
2017
International audience; We aimed to search for mutations in the germline and somatic DNA of the TEK gene and to analyze the expression level of Src and phospho- Src (p-Src) in tumor and healthy tissues from patients with facial cutaneo-mucosal venous malformations (VMCM). Eligible patients from twelve families and thirty healthy controls were recruited respectively at the Departments of Stomatology and Oral Surgery, and Transfusion Medicine of Tlemcen University Medical Centre. Immunoblot analyses of Src and p-Src were performed after direct DNA sequencing. No somatic or germline mutations were found in all the 23 exons and their 5' and 3' intronic flanking regions, except for one case in w…
International prevalence and risk factors evaluation for drug-resistant Streptococcus pneumoniae pneumonia
2019
Objective: Streptococcus pneumoniae is the most frequent bacterial pathogen isolated in subjects with Community-acquired pneumonia (CAP) worldwide. Limited data are available regarding the current global burden and risk factors associated with drug-resistant Streptococcus pneumoniae (DRSP) in CAP subjects. We assessed the multinational prevalence and risk factors for DRSP-CAP in a multinational point-prevalence study. Design: The prevalence of DRSP-CAP was assessed by identification of DRSP in blood or respiratory samples among adults hospitalized with CAP in 54 countries. Prevalence and risk factors were compared among subjects that had microbiological testing and antibiotic susceptibility…
HLA-C1 ligands are associated with increased susceptibility to systemic lupus erythematosus.
2017
Recently, the role of killer cell immunoglobulin-like receptor (KIR) in autoimmune diseases has received increasing attention. The present study was undertaken to determine the association of KIR genes and the human leukocytes antigen (HLA) ligands with Systemic Lupus Erythematosus (SLE) and accompanying oxidative stress. Presence or absence of 17 KIR and 5 HLA loci was performed using the polymerase chain reaction-sequence specific primer (PCR-SSP) method by case-control study. A total of 45 SLE patients, and 60 healthy controls, all of Sicilian descent, were enrolled. Plasma values of the anti-oxidant molecule Taurine were determined in all subjects by capillary electrophoresis UV detecti…
Stenosis coexists with compromised α1-adrenergic contractions in the ascending aorta of a mouse model of Williams-Beuren syndrome
2020
Williams-Beuren syndrome (WBS) is a rare disorder caused by a heterozygous deletion of 26-28 contiguous genes that affects the brain and cardiovascular system. Here, we investigated whether WBS affects aortic structure and function in the complete deletion (CD) mouse model harbouring the most common deletion found in WBS patients. Thoracic aortas from 3-4 months-old male CD mice and wild-type littermates were mounted in wire myographs or were processed for histomorphometrical analysis. Nitric oxide synthase (NOS) isoforms and oxidative stress levels were assessed. Ascending aortas from young adult CD mice showed moderate (50%) luminal stenosis, whereas endothelial function and oxidative str…
PDXK mutations cause polyneuropathy responsive to pyridoxal 5′‐phosphate supplementation
2019
OBJECTIVE: To identify disease-causing variants in autosomal recessive axonal polyneuropathy with optic atrophy and provide targeted replacement therapy. METHODS: We performed genome-wide sequencing, homozygosity mapping, and segregation analysis for novel disease-causing gene discovery. We used circular dichroism to show secondary structure changes and isothermal titration calorimetry to investigate the impact of variants on adenosine triphosphate (ATP) binding. Pathogenicity was further supported by enzymatic assays and mass spectroscopy on recombinant protein, patient-derived fibroblasts, plasma, and erythrocytes. Response to supplementation was measured with clinical validated rating sc…