Search results for "MUTATION"
showing 10 items of 2830 documents
Mitochondrial Fatty Acid β-Oxidation Inhibition Promotes Glucose Utilization and Protein Deposition through Energy Homeostasis Remodeling in Fish.
2020
BACKGROUND: Fish cannot use carbohydrate efficiently and instead utilize protein for energy supply, thus limiting dietary protein storage. Protein deposition is dependent on protein turnover balance, which correlates tightly with cellular energy homeostasis. Mitochondrial fatty acid β-oxidation (FAO) plays a crucial role in energy metabolism. However, the effect of remodeled energy homeostasis caused by inhibited mitochondrial FAO on protein deposition in fish has not been intensively studied. OBJECTIVES: This study aimed to identify the regulatory role of mitochondrial FAO in energy homeostasis maintenance and protein deposition by studying lipid, glucose, and protein metabolism in fish. M…
Lamivudine/Adefovir Treatment Increases the Rate of Spontaneous Mutation of Hepatitis B Virus in Patients.
2016
The high levels of genetic diversity shown by hepatitis B virus (HBV) are commonly attributed to the low fidelity of its polymerase. However, the rate of spontaneous mutation of human HBV in vivo is currently unknown. Here, based on the evolutionary principle that the population frequency of lethal mutations equals the rate at which they are produced, we have estimated the mutation rate of HBV in vivo by scoring premature stop codons in 621 publicly available, full-length, molecular clone sequences derived from patients. This yielded an estimate of 8.7 × 10-5 spontaneous mutations per nucleotide per cell infection in untreated patients, which should be taken as an upper limit estimate becau…
Microenvironment in neuroblastoma: isolation and characterization of tumor-derived mesenchymal stromal cells
2018
Background It has been proposed that mesenchymal stromal cells (MSCs) promote tumor progression by interacting with tumor cells and other stroma cells in the complex network of the tumor microenvironment. We characterized MSCs isolated and expanded from tumor tissues of pediatric patients diagnosed with neuroblastomas (NB-MSCs) to define interactions with the tumor microenvironment. Methods Specimens were obtained from 7 pediatric patients diagnosed with neuroblastoma (NB). Morphology, immunophenotype, differentiation capacity, proliferative growth, expression of stemness and neural differentiation markers were evaluated. Moreover, the ability of cells to modulate the immune response, i.e. …
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…
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…
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…
GLRB allelic variation associated with agoraphobic cognitions, increased startle response and fear network activation: a potential neurogenetic pathw…
2017
Contains fulltext : 177350.pdf (Publisher’s version ) (Closed access) The molecular genetics of panic disorder (PD) with and without agoraphobia (AG) are still largely unknown and progress is hampered by small sample sizes. We therefore performed a genome-wide association study with a dimensional, PD/AG-related anxiety phenotype based on the Agoraphobia Cognition Questionnaire (ACQ) in a sample of 1370 healthy German volunteers of the CRC TRR58 MEGA study wave 1. A genome-wide significant association was found between ACQ and single non-coding nucleotide variants of the GLRB gene (rs78726293, P=3.3 x 10-8; rs191260602, P=3.9 x 10-8). We followed up on this finding in a larger dimensional AC…
9q33.3q34.11 microdeletion: new contiguous gene syndrome encompassing STXBP1, LMX1B and ENG genes assessed using reverse phenotyping
2016
International audience; The increasing use of array-CGH in malformation syndromes with intellectual disability could lead to the description of new contiguous gene syndrome by the analysis of the gene content of the microdeletion and reverse phenotyping. Thanks to a national and international call for collaboration by Achropuce and Decipher, we recruited four patients carrying de novo overlapping deletions of chromosome 9q33.3q34.11, including the STXBP1, the LMX1B and the ENG genes. We restrained the selection to these three genes because the effects of their haploinsufficency are well described in the literature and easily recognizable clinically. All deletions were detected by array-CGH …
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…
Evolution of transmitted HIV-1 drug resistance and viral subtypes circulation in Italy from 2006 to 2016
2018
Objectives: The aim was to evaluate the evolution of transmitted HIV-1 drug resistance (TDR) prevalence in antiretroviral therapy (ART)-naïve patients from 2006 to 2016. Methods: HIV-1 sequences were retrieved from the Antiviral Response Cohort Analysis (ARCA) database and TDR was defined as detection of at least one mutation from the World Health Organization (WHO) surveillance list. Results: We included protease/reverse transcriptase sequences from 3573 patients; 455 had also integrase sequences. Overall, 68.1% of the patients were Italian, the median CD4 count was 348 cells/μL [interquartile range (IQR) 169–521 cells/μL], and the median viral load was 4.7 log 10 HIV-1 RNA copies/mL (IQR …