Instanton moduli spaces and bases in coset conformal field theory

Recently proposed relation between conformal field theories in two dimensions and supersymmetric gauge theories in four dimensions predicts the existence of the distinguished basis in the space of local fields in CFT. This basis has a number of remarkable properties, one of them is the complete factorization of the coefficients of the operator product expansion. We consider a particular case of the U(r) gauge theory on C^2/Z_p which corresponds to a certain coset conformal field theory and describe the properties of this basis. We argue that in the case p=2, r=2 there exist different bases. We give an explicit construction of one of them. For another basis we propose the formula for matrix elements.Comment: 31 pages, 3 figure

Expanding Clinical Presentations Due to Variations in THOC2 mRNA Nuclear Export Factor

Multiple TREX mRNA export complex subunits (e.g., THOC1, THOC2, THOC5, THOC6, THOC7) have now been implicated in neurodevelopmental disorders (NDDs), neurodegeneration and cancer. We previously implicated missense and splicing-defective THOC2 variants in NDDs and a broad range of other clinical features. Here we report 10 individuals from nine families with rare missense THOC2 variants including the first case of a recurrent variant (p.Arg77Cys), and an additional individual with an intragenic THOC2 microdeletion (Del-Ex37-38). Ex vivo missense variant testing and patient-derived cell line data from current and published studies show 9 of the 14 missense THOC2 variants result in

Novel heterozygous mutations in the PGAM2 gene with negative exercise testing

Pathogenic variants in the PGAM2 gene are associated with glycogen storage disease type X (GSDX) and is characterized by exercise induced muscle cramping, weakness, myoglobinuria, and often tubular aggregates in skeletal muscle. We report here a patient diagnosed with GSDX at 52 years of age with a normal increase in post-exercise lactate with both anaerobic and aerobic exercise. Genetic testing found two novel PGAM2 variants (c.426C > A, p.Tyr142Ter and c.533delG, p.Gly178Alafs*31)

Leigh syndrome associated with mitochondrial complex I deficiency due to novel mutations In NDUFV1 and NDUFS2

Item does not contain fulltextLeigh syndrome (LS) is a progressive neurodegenerative disease caused by either mitochondrial or nuclear DNA mutations resulting in dysfunctional mitochondrial energy metabolism. Mutations in genes encoding for subunits of the respiratory chain or assembly factors of respiratory chain complexes are often documented in LS cases. Nicotinamide adenine dinucleotide (NADH):ubiquinone oxidoreductase (complex I) enzyme deficiencies account for a significant proportion of mitochondrial disorders, including LS. In an attempt to expand the repertoire of known mutations accounting for LS, we describe the clinical, radiological, biochemical and molecular data of six patients with LS found to have novel mutations in two complex I subunits (NDUFV1 and NDUFS2). Two siblings were homozygous for the previously undescribed R386C mutation in NDUFV1, one patient was a compound heterozygote for the R386C mutation in NDUFV1 and a frameshift mutation in the same gene, one patient was a compound heterozygote for the R88G and R199P mutations in NDUFV1, and two siblings were compound heterozygotes for an undescribed E104A mutation in NDUFS2. After the novel mutations were identified, we employed prediction models using protein conservation analysis (SIFT, PolyPhen and UCSC genome browser) to determine pathogenicity. The R386C, R88G, R199P, and E104A mutations were found to be likely pathogenic, and thus presumably account for the LS phenotype. This case series broadens our understanding of the etiology of LS by identifying new molecular defects that can result in complex I deficiency and may assist in targeted diagnostics and/or prenatal diagnosis of LS in the future

Kinetic studies on the inhibition of creatine kinase activity by branched‐chain α‐amino acids in the brain cortex of rats

Maple syrup urine disease (MSUD) is a metabolic disorder biochemically characterized by the accumulation of branched-chain α-amino acids (BCAA) and their branched-chain α-keto acids (BCKA) in blood and tissues. Neurological dysfunction is usually present in the patients, but the mechanisms of brain damage in this disease are far from be understood. The main objective of this study was to investigate the mechanisms by which BCAA inhibit creatine kinase activity, a key enzyme of energy homeostasis, in the brain cortex of 21-day-old Wistar rats. For the kinetic studies, Lineweaver–Burk and a modification of the Chevillard et al. plots were used to characterize the mechanisms of enzyme inhibition. The results indicated that BCAA inhibit creatine kinase by competition with the substrates phosphocreatine and ADP at the active site. Considering the crucial role creatine kinase plays in energy homeostasis in brain, if these effects also occur in the brain of MSUD patients, it is possible that inhibition of this enzyme activity may contribute to the brain damage found in this disease. In this case, it is possible that creatine supplementation to the diet might benefit MSUD patients