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Purpose: Mutations in the glucokinase (GCK) gene are associated with altered blood glucose and lipid concentrations. Our aim was to assess the effects on HbA1c and serum lipid levels of single nucleotide polymorphisms (SNPs) in 2 genes encoding proteins that interact with glucokinase: glucose-6-phospatase catalytic subunit 2 (G6PC2) and glucokinase regulatory protein (GCKR). Methods: The study group included 129 children with GCK- MODY from the Polish Registry of Monogenic Diabetes and 395 with type 1 diabetes (T1DM), in whom we genotyped 2 SNPs in G6PC2 (rs560887) and GCKR (rs1260326). Lipid concentrations were assessed in fasting serum samples. Results: Total and HDL cholesterol concentrations were significantly lower in the GCK- MODY group than in patients with T1DM (167.5 ± 32.5 mg/dl vs. 174.4 ± 31.1 mg/dl, p = 0.0435 and 48.42 ± 14.3 mg/dl vs. 58.7 ± 12.7 mg/dl, p < 0.0001, respectively). No differences in genotype distributions were found except for underrepresentation of GCKR TT homozygotes among GCK- MODY patients (10.9 % in GCK-MODY vs. 17.7 % in T1DM, p = 0.0651). GCKR genotypes showed significant associations with lipid profiles and HbA1c levels, whereas no such associations were noted for G6PC2 . After adjustment for confounders, TT homozygotes were shown to have higher total cholesterol and marginally higher LDL cholesterol and triglyceride levels (p = 0.0245, p = 0.0657 and p = 0.0550, respectively). The difference between TT homozygotes and other genotypes was similar in magnitude within the GCK-MODY and T1DM groups. No significant interactions between the type of diabetes and the GCKR or G6PC2 genotype were detected. Conclusions: Individuals who are homozygous TT at rs1260326 of the GCKR gene have higher triglyceride, total and LDL cholesterol levels regardless of the presence of GCK mutations. [ABSTRACT FROM AUTHOR]

The magnetic investigations as a function of the temperature and magnetic field for the rubidium neodymium double tungstate RbNd(WO4)2 single crystal have been performed. The magnetization was measured in the temperature range from 4.2 to 100 K and for the magnetic field up to 1.5 T. The crystal field and exchange parameters were found. [ABSTRACT FROM AUTHOR]

Cytosolic phospholipase A2 (cPLA2) group IVα is a critical enzyme involved in the liberation of arachidonic acid from cellular membranes. cPLA2−/− mice have reduced allergen-induced bronchoconstriction and bronchial hyperresponsiveness. The goal of this study was to investigate polymorphisms of the (CA)n and (T)n microsatellites and surrounding regions in the cPLA 2α gene promoter. We analysed the cPLA 2 promoter regions containing (CA)n and (T)n repeats in 87 patients with severe asthma and in 48 control subjects by bidirectional sequencing. Functional studies were performed utilizing reporter genes derived from subjects with varying numbers of these repeats, and on constructs with a series of deletions. We found that the (CA)n and (T)n regions are polymorphic and that constructs with CA or T repeats or CA and T repeats deleted revealed, respectively, a 41·8 ± 7%, 22·3 ± 5% and 100 ± 20% increase in reporter gene activity. A lower number of CA or T repeats caused higher cPLA 2 promoter luciferase activity. The group of shorter alleles of the (CA)n microsatellite region ( n = 12–18) ( Pcor = 0·00006), and the group of shorter alleles of (T)n repeats region ( n = 17–38) ( Pcor = 0·0039) occurred significantly more often in patients with severe asthma. We also found novel SNPs in positions −292 C > G, −185 A > C, −180 T > C and −165 A > C. Two of them were associated with the severe asthma phenotype: −180T allele ( Pcor = 0·03996) and −185 A allele ( Pcor = 0·03966). These results demonstrate that (CA)n and (T)n repeats may have an influence on cPLA2 transcription which might play a role in severe asthma pathogenesis. [ABSTRACT FROM AUTHOR]

The electron paramagnetic resonance (EPR) of Yb3+ ions in a KY(WO4)2 single crystal was investigated at T=4.2 K and fixed frequency of 9.38 GHz. The resonance absorption observed on the lowest Kramers doublet represents the complex superposition of three spectra, corresponding to the ytterbium isotopes with different nuclear moments. The EPR spectrum is characterized by a strong anisotropy of the g-factors. The temperature dependence of the g-factors is shown to be caused by the strong spin-orbital and orbital-lattice coupling. The resonance lines broaden with increasing temperature due to the short spin-lattice relaxation times. [ABSTRACT FROM AUTHOR]

We study the Melnikov criterion for a global homoclinic bifurcation and possible transition to chaos for a single degree of freedom nonlinear oscillator. This provides a systematic method of treatment for an arbitrary potential expressed as a fourth order polynomial. The equation of motion has external excitation and a Duffing type nonlinearity with one or two unsymmetric potential wells. [ABSTRACT FROM AUTHOR]

Association and linkage studies of β2-adrenergic receptor ( β2-ADR) polymorphisms in relation to the expression of asthmatic phenotypes and immune regulatory mechanisms have shown inconsistent results. In order to analyse the relevance of particular combinations of single nucleotide polymorphisms (SNPs) or haplotypes of β2-ADR gene to bronchial asthma, bronchodilator response and total immunoglobulin E (IgE) we determined by direct DNA sequencing five SNPs (in positions: −47, −20, 46, 79, 252) in a group of 180 Caucasian subjects (110 patients with grass allergy and 70 nonatopic controls). The eight different β2-ADR haplotypes were identified, with three the most common of them representing 92% of the studied cohort. Significantly higher (pcor = 0.0045) bronchodilator response was observed in patients with homozygotic genotype 46A/A in comparison with respective homo- and hetero-zygotes. There was no significant difference in bronchodilator response when β2-ADR haplotypes were analysed. Significantly higher (pcor = 0.0005) total IgE levels were found in patients with β2-ADR haplotype −47T/−20T/46A/79C/252G and homozygotic carriers of 46A (pcor = 0.0015) and 79C (pcor = 0.003) genotypes. No significant associations were found in regards to asthmatic phenotype and atopy. These results indicate that depending on phenotype studied, either an individual β2-ADR SNP or β2-ADR haplotype might affect disease manifestation. [ABSTRACT FROM AUTHOR]

The optical absorption and luminescence properties of potassium-holmium and potassium-erbium double tungstates have been studied. It is established that the potassium-holmium double tungstate belongs to a group of biaxial and pleochromic crystals. The emission and excitation spectra of the KHo(WO4)2 and KEr(WO4)2 single crystals were measured at room temperature. [ABSTRACT FROM AUTHOR]

An acute phase of psoriasis can be induced by cytokines involved in psoriatic pathogenic phenomena. Activation of the acute phase reaction by proinflammatory cytokines (including interleukins 1 and 6, tumour necrosis factor α) may account for systemic symptoms in severe psoriasis, especially in pustular and arthropathic forms of this disease. To study the activity of selected acute phase proteins in psoriatics before and after effective treatment. Plasma concentrations of C-reactive protein (CRP) and α2-macroglobulin (α2-MG) were examined in 175 males with medium–severe and severe psoriasis in the active stage, before treatment and in remission achieved with various treatments (local, acitretin, psoralen + ultraviolet A, retinoid + psoralen + UVA [Re-PUVA] methotrexate, cyclosporin A). Clinical activity of psoriasis was evaluated using the Psoriasis Area and Severity Index score, ranging from 18 to 70.8 (mean 29.2). Measurements were done using the immunoenzymatic method. The control group consisted of 30 healthy male volunteers. In the active stage of disease highly increased plasma levels of both CRP and α2-MG were found ( P < 0.001). It appeared that efficacious treatment was correlated with a considerable decrease of the proteins examined towards the control values. Mean levels of α2-MG after treatment did not differ significantly from those of controls ( P > 0.15). However, despite their strong decrease following all methods of treatment, mean plasma levels of CRP remained significantly elevated during remission compared with those of the healthy controls ( P < 0.001). The results of this study indicate that in medium–severe and severe psoriasis the acute phase response can be initiated and is not completely extinguished in phases of clinical remission. [ABSTRACT FROM AUTHOR]

Several in-vitro studies have shown that endothelins (ET) may inhibit synthesis of progesterone and prevent luteinization of granulosa cells. In the present study, a specific radioimmunoassay was used to evaluate the correlation between concentrations of active (21 residue) ET and ovarian steroids in 47 samples of human follicular fluid (FF) following gonadotrophin stimulation for in-vitro fertilization (IVF) protocols. An isoform non-selective antibody was used in the radioimmunoassay, which recognized the C-terminal structure of the 21 residue ET, and therefore did not crossreact with their weakly active precursors - big ET. In pooled samples of follicular fluid (FF), the concentration of 21 amino acid ET correlated negatively with diameter of the follicles (r = -0.31, P < 0.05) and progesterone concentrations in FF (r = -0.56, P < 0. 001). A positive relationship (non-significant) was found between ET and testosterone concentrations. No correlation between ET and oestradiol was observed. The within-patient correlation coefficients were also evaluated in women from whom three or more samples of FF were obtained. ET were markedly inversely correlated with follicle size in all cases, and with progesterone in five of seven women. Five of seven patients also showed significant positive correlation of ET with testosterone. The results demonstrate clinical evidence that active ET play an important role in regulation of follicle development, especially in the inhibition of premature luteinization of granulosa cells. [ABSTRACT FROM AUTHOR]

The specific heat C(T) of the monoclinic RbDy(WO4 )2 crystal has been studied at very low temperatures 0.2≤T≤ 1.9 K and in magnetic fields 0≤H≤ 0.38 T. The Neel temperature was shown to be equal to TN = 0.818 ± 0.005 K. The experimental value of the effective exchange parameter was obtained to be equal to J/k = − 0.798 K. The C T ) dependence below Neel temperature 0.5TNN ) is well described by 2D Ising model, whereas in the temperature region close above TN (1.01 TNN) it can be described by neither 2D, nor 3D Ising model. The experimental and theoretical H-TN diagrams for field H | a are in a reasonable agreement for simple quadratic lattice. [ABSTRACT FROM AUTHOR]

The article discusses research on population-based estimates for double diabetes in patients with glucokinase monogenic diabetes. Topics covered include the establishment of large registries and epidemiologic estimates, the mutation of the glucokinase gene that causes the development of monogenic diabetes, and the overall prevalence of diabetes in Poland.

The potassium holmium double tungstate was prepared by using top seeded solution growth technique. Structural investigations have been performed at room temperature. The KHo(WO4)2 single crystal belongs to the monoclinic space group C2=c with the unit-cell parameters: a = 10:624(2) Å, b = 10:352(2) Å, c = 7:5434(15) Å, β = 130:78(3)°, and Z = 4. The atomic coordinates, isotropic and anisotropic displacement parameters and interionic distances for the studied structure were determined. [ABSTRACT FROM AUTHOR]

Spin and orbital magnetic moments of rhenium in AA′FeReO6 double perovskites (A,A′=Ba, Sr, and Ca) have been directly probed employing x-ray magnetic circular dichroism at the Re L2,3 edges. A considerable orbital magnetic moment is observed in all the compounds studied, which confirm theoretical predictions of unquenched Re orbital moment despite its octahedral coordination. Relative orbital-to-spin moment ratio alters with lattice distortion from mL/mS=-0.285 to -0.337 from Ba2FeReO6 to Ca2FeReO6, respectively. Moreover, the spin moment of Re ion scales with Curie temperature, the most relevant property in spin electronics application of the compounds studied. [ABSTRACT FROM AUTHOR]