Humoral Responses to Diverse Autoimmune Disease-Associated Antigens in Multiple Sclerosis

To compare frequencies of autoreactive antibody responses to endogenous disease-associated antigens in healthy controls (HC), relapsing and progressive MS and to assess their associations with clinical and MRI measures of MS disease progression.

Real-time RT-PCR threshold cycles value for Kir6.1 from the blood correlates with parameters of vascular function: a potential for the vascular function biomarker?

Abstract We examined the presence of KATP channel subunits, Kir6.1 and SUR2B, mRNAs in the blood and vascular function in healthy volunteers (41 males, 34 females). Real-time reverse transcriptase (RT)-PCR threshold cycles (Ct) was used as an indicator of mRNA levels. Baseline skin perfusion and the post-occlusion reactive hyperemia response exhibited a significant positive correlation with Ct for Kir6.1. There was no correlation between Kir6.1 Ct and brachial artery flow-mediated dilatation. Gender had no influence on relationships between blood Kir6.1 Ct and vascular function. We conclude that blood Kir6.1 mRNA levels could be potentially used as a biomarker of the vascular function.

Unsuccessful switch from insulin to sulfonylurea therapy in permanent neonatal diabetes mellitus due to an R201H mutation in the KCNJ11 gene: a case report

Mutations in KCNJ11 are a common cause of permanent neonatal diabetes mellitus. Previously, all patients carrying an R201H mutation in the KCNJ11 gene showed successful switches from insulin to sulfonylurea. Here, we report an unsuccessful switch in an 18-year-old patient carrying the common R201H mutation in the KCNJ11 gene.

Impact of the sulfonylurea receptor 1 (SUR1) exon 16-3c/t polymorphism on acute hyperglycaemia in type 2 diabetic patients

Epidemiological data collected over the last few decades have demonstrated the significant role of acute (especially postprandial) hyperglycaemia in the development of macrovascular complications in patients with type 2 diabetes. However, the influence of SUR1 exon 16-3c/t polymorphism on impaired insulin secretion during acute hyperglycaemic episodes has not yet been evaluated. We studied 40 type 2 diabetic patients. Single nucleotide polymorphism in the sulfonylurea receptor gene was examined by means of PCR-RLFP. In every patient, fasting insulin, proinsulin, C-peptide and 1,5-anhydro-d-glucitol concentrations were assayed as markers of insulin secretion, peripheral resistance to insulin, and acute hyperglycaemia. The distribution of SUR1 exon 16-3c/t polymorphism was tt 35%, tc -40%, and cc -25%. By means of analysis of covariance, it was revealed that 1,5-anhydro-d-glucitol plasma levels are associated with SUR1 exon 16-3c/t polymorphism. However, the HOMA(IR) score influenced 1,5-anhydro-d-glucitol levels in plasma at a higher level of statistical power than the genetic variant. Our results suggest that SUR1 exon 16-3c/t polymorphism is only a partial determinant of acute hyperglycaemia-cardiovascular risk factor in type 2 diabetes.

[Study on the relationship between sulfonylurea receptor 1 gene polymorphism and type 2 diabetes mellitus]

To study whether the 3c/t polymorphism of the sulfonylurea receptor 1 (SUR1) gene exon16 increased the risk of type 2 diabetes mellitus in type 2 diabetes mellitus pedigrees in Han population in south area of China. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used in 46 type 2 diabetes mellitus pedigrees. The polymorphism in SUR1 was tested and analyzed by Mantel-Haenszel chi(2) test. Frequencies of SUR1-3c/t polymorphism had no significant difference between type 2 diabetes mellitus and normal relatives (genotypes chi(2)=3.224, P=0.199; frequency of allele chi(2)=1.250, P=0.264). In all subjects, type 2 diabetes mellitus and normal relatives, SUR1-3c/t genotypes were listed (cc: 29.3%, 30.2%, 28.3%; ct: 50.7%, 53.8%, 47.2%; tt: 20%, 16.0%, 24.5% respectively). The frequencies of c were 54.7%, 57.1% and 51.9% respectively. The frequency of c is lower than Han population in northern China. The results show that SUR1 exon16-3c/t polymorphism is not associated with type 2 diabetes mellitus in the population.

ATP-sensitive K+ and Ca2+-activated K+ channels in lamprey ( Petromyzon marinus) red blood cell membrane

The patch-clamp technique was used to demonstrate the presence of ATP-sensitive K(+) channels and Ca(2+)-activated K(+) channels in lamprey ( Petromyzon marinus) red blood cell membrane. Whole-cell experiments indicated that the membrane current under isosmotic (285 mosmol l(-1)) conditions is carried by K(+). In the inside-out configuration an ATP-sensitive K(+) channel (70-80 pS inward, 35-40 pS outward) was present in 35% of patches. Application of ATP to the intracellular side reduced unitary current with half-maximal inhibition in the range 10-100 microM. A block was obtained with 100 microM lidocaine and inhibition was obtained with 0.5 mM barium acetate. A Ca(2+)-activated K(+) channel (25-30 pS inward, 10-15 pS outward) was present in 57% of patches. Inhibition was produced by 10 mM TEA and 500 nM apamin and sensitivity to Ba(2+) was lower than for ATP-sensitive channels. No spontaneous channel activity was recorded in the cell-attached configuration under isotonic conditions. With hypotonic saline 68% of patches showed spontaneous single-channel activity, and, of 75 active patches, 66 cell-attached patches showed channel activity corresponding to Ca(2+)-activated K(+) channels.