Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study.

The development of new chiral ligands with simple and modular structure represents a challenging direction in the design of efficient homogeneous transition metal catalysts. Herein, we report on the asymmetric hydrogenation of prochiral ketones catalyzed by the iridium complexes of simple alkane-diyl-based P,N,O-type chiral ligands with a highly modular structure. The role of (i) the P-N and N-O backbone in the potentially tridentate ligands, (ii) the number, position and relative configuration of their stereogenic elements and (iii) the effect of their NH and OH subunits on the activity and enantioselectivity of the catalytic reactions are studied. The systematic variation in the ligand structure and the comparative catalytic experiments shed light on different mechanistic aspects of the iridium-catalyzed reaction. The catalysts containing the simple alkane-diyl-based ligands with central chirality provided high enantioselectivities (up to 98% ee) under optimized reaction conditions and proved to be active and selective even at very high substrate concentrations (100 mmol substrate/mL solvent).

Characterization of Various Titanium-Dioxide-Based Catalysts Regarding Photocatalytic Mineralization of Carbamazepine also Combined with Ozonation.

Titanium-dioxide-based semiconductors proved to be appropriate for photocatalytic application to efficiently degrade emerging organic pollutants such as various herbicides, pesticides, and pharmaceuticals in waters of environmental importance. The characterization of various TiO2 catalysts, both bare and modified (Ag- and/or N-doped), by mechanochemical treatment was carried out in this work, regarding their structure, morphology, and photocatalytic activity. For the latter investigations, carbamazepine, an antidepressant, proved to be applicable and versatile. The photocatalytic behavior of the catalysts was studied under both UV and visible light. Besides the decomposition efficiency, monitoring the intermediates provided information on the degradation mechanisms. Mechanochemical treatment significantly increased the particle size (from 30 nm to 10 µm), causing a considerable (0.14 eV) decrease in the band gap. Depending on the irradiation wavelength and the catalyst, the activity orders differed, indicating that, in the mineralization processes of carbamazepine, the importance of the different oxidizing radicals considerably deviated, e.g., Ag-TiO2 < DP25-TiO2 < ground-DP25-TiO2 < N-TiO2 ≈ N-Ag-TiO2 for O2•− and N-TiO2 ≈ Ag-TiO2 < N-Ag-TiO2 < ground-DP25-TiO2 ≈ DP25-TiO2 for HO• generation under UV irradiation. Toxicity studies have shown that the resulting intermediates are more toxic than the starting drug molecule, so full mineralization is required. This could be realized by a synergistic combination of heterogeneous photocatalysis and ozonation.

Association of PPAR polymorphisms with cytokine levels in allergic rhinitis.

Our aim was to study the association of Pro12Ala and exon6 C161T polymorphisms of PPARgamma and intron7 G/C polymorphisms of PPAR-alpha with clinical symptoms, peak nasal inspiratory flow values, serum soluble TNF-alpha, TNF-R1, Fas, Fas ligand and IgE concentrations in patients with seasonal allergic rhinitis during and after pollen season. We performed a follow-up study of 66 Hungarian patients with seasonal allergic rhinitis and 180 healthy referent subjects. We used PCR-RFLP technique and ELISA. The distribution of mutant alleles of PPAR-gamma and -alpha did not differ in patients and referent subjects. Patients carrying the mutant 12Ala, exon6 161T alleles of PPAR-gamma and intron7 C allele of PPAR-alpha had significantly higher clinical symptom score values, TNF-alpha and IgE levels and lower peak nasal inspiratory flow values during and after pollen season. The results indicated that nuclear receptors PPAR-gamma and PPAR-alpha are involved in the regulation of inflammatory mediator production in patients with seasonal allergic rhinitis and polymorphisms of the receptors are very likely to contribute to the heterogeneity of clinical and immunological parameters of allergic patients.

Synthesis, photochemistry, and photophysics of butadiene derivatives: influence of the methyl group on the molecular structure and photoinduced behavior.

Novel butadiene derivatives display diverse photochemistry and photophysics. Excitation of 2-methyl-1-(o-vinylphenyl)-4-phenylbutadiene leads to the dihydronaphthalene derivative, whereas photolysis of the corresponding model o-methyl analogue results in the formation of the naphthalene-like derivative, deviating from the nonmethylated analogue of the prior starting compound and producing benzobi- and -tricyclic compounds. The effect of the methyl substituents is even more dramatic in the case of the dibutadienes. The parent unsubstituted compound undergoes photoinduced intramolecular cycloaddition giving benzobicyclo[3.2.1]octadiene, whereas the photochemical reaction of the corresponding dimethylated derivative shows only geometrical isomerization due to the steric effect of the substituents. Methyl groups on the butadiene backbones reduce the extent of conjugation, causing a blue-shift of the characteristic absorption band. The fluorescence efficiency is dramatically decreased, as a consequence of nonplanarity and reduced rigidity of the molecules due to the crowding by the methyl and phenyl groups together. Four molecules of very similar structures show dramatically different photoinduced behavior, revealing how changes of the nature and position of the substituents are valuable in understanding the photophysics and photochemistry of these types of compounds.

The effect of the position of methyl substituents on photophysical and photochemical properties of [Ru(x,x'-dmb)(CN)4]2- complexes: experimental confirmation of the theoretical predictions.

The molecular geometry, electronic structure and electronic spectra and the energy levels of the molecular orbitals responsible for the photophysical characteristics of a series of solvent tunable [Ru(x,x'-dmb)(CN)(4)](2-) complexes (where x,x'-dmb = x,x'-dimethyl-2,2'-bipyridine) were calculated by density-functional theory-based quantum chemical methods, with the purpose of proposing for experimental study the best candidate for sensitizing electron- and energy transfer processes or for light induced structural changes in the molecule. The methods applied include geometry optimization using the B3LYP functional combination and various basis sets, time-dependent density functional theory with the B3LYP and PBE0 functionals, with and without explicit inclusion of coordinated solvent H(2)O molecules and the conductor-like polarizable continuum model for solvation. The accuracy of the theoretical predictions was tested by experiments: the model compounds have been synthesized and characterized by various spectroscopic methods, such as (1)H-NMR, UV-Vis absorption and emission spectroscopy and by cyclic voltammetry. Excellent correlation was found between the theoretically calculated and the experimentally determined photophysical and photochemical characteristics. The electronic transition energies measured in water are superbly reproduced by TD-PBE0 and well by TD-B3LYP, but the performance of both functionals is worse if the solvent is acetonitrile.

PPAR-gamma2 pro12Ala polymorphism is associated with post-challenge abnormalities of glucose homeostasis in children and adolescents with obesity.

AIM: The aim of the study was to investigate the association between PPAR-gamma2 Pro12Ala polymorphism and laboratory characteristics of carbohydrate metabolism in children and adolescents with obesity. In addition, serum levels of tumor necrosis factor (TNF)-alpha, and soluble form of its receptors (sTNFR1 and sTNFR2) were assessed. METHODS: In a cross-sectional study, 79 obese children and adolescents of Caucasian origin were investigated. PPAR-gamma2 Pro12Ala polymorphism was determined using polymerase chain reaction--restriction fragment length polymorphism technique. Serum levels of TNF-alpha, sTNFR1 and sTNFR2 were measured by enzyme amplified sensitivity immunoassay. RESULTS: The minor Ala allele frequency was found to be 14.56% in our cohort. No significant differences in age, BMI, waist circumference, blood pressure, serum lipid, uric acid, TNF-alpha, sTNFR1 and sTNFR2 values were found between carriers of the Ala allele (Pro/Ala and Ala/Ala; n=21) vs. homozygous carriers of the Pro allele (Pro/Pro; n=58). However, post-challenge (120 min) plasma glucose and insulin values were significantly lower in Ala allele carriers vs. homozygous Pro allele carriers (6.56 +/- 0.26 vs. 7.36 +/- 0.25 mmol/L and 65.9 +/- 13.8 vs. 111.8 +/- 20.7 microU/mL, respectively; p < 0.05); while no significant differences were found at fasting state. CONCLUSIONS: The association between PPAR-gamma2 Prol2Ala polymorphism and glucose metabolism is already present in children and adolescents with obesity who might be at the very beginning of the natural course of type 2 diabetes. At this stage, higher insulin sensitivity can be detected in Ala allele carriers compared to homozygous Pro subjects at post-challenge but not in fasting state; however, the TNF-system seems not to be involved in the alteration of glucose homeostasis due to PPAR-gamma2 Pro12Ala polymorphism.

Association of TLR-4 and TNF-alpha polymorphisms with clinical symptoms and cytokine levels in patients with allergic rhinitis.

Our objective was to determine the frequency of TNF-alpha -238, -308 G/A promoter and TLR-4 299 D/G and 399 T/I polymorphisms in healthy population and in patients with seasonal allergic rhinitis, and to examine its influences on serum TNF-alpha, TNF receptor-1, Fas, Fas-ligand, IgE levels and on clinical symptoms. A pilot study was performed in 66 patients with seasonal allergic rhinitis to ragweed pollen and 161 non-allergic subjects using PCR-RFLP technique and ELISA. Carriers of the -238A and -308G alleles have significantly higher TNF-alpha and IgE levels, clinical score values and lower peak nasal flow (PNIF) values during and after ragweed pollen season. Patients with the 299G/399I alleles of the TLR-4 gene have significantly lower TNF-alpha, Fas, FasL and IgE levels, clinical scores and higher PNIF values during and after pollen season. The -238A and -308G polymorphisms of the TNF-alpha promoter and 299D/399T polymorphisms of the TLR-4 gene are associated with more pronounced clinical symptoms, higher cytokine and IgE levels, and low PNIF values. These polymorphisms are very likely to contribute to the heterogeneity of clinical and laboratory parameters of patients.

Association between toll-like receptor polymorphisms and serum levels of tumor necrosis factor-alpha and its soluble receptors in obese children.

BACKGROUND: In obesity, increased tumor necrosis factor (TNF)-alpha level is involved in the development of insulin resistance. Toll-like receptor (TLR)-4 and TLR2 are expressed in adipose tissue, and polymorphisms of these receptors may influence TNF-alpha secretion from adipocytes. In our study, TNF-alpha, soluble TNF receptor 1 (sTNFR1), and soluble TNF receptor 2 (sTNFR2) levels were determined, and any association between polymorphisms of TLR4 (D299G, T399I), TLR2 (R753Q, R677W), and cytokine levels was assessed in obese children and non-obese control subjects. MATERIAL/METHODS: In a cross-sectional study, 79 obese children and 42 matched non-obese control children were investigated. Cytokine levels were measured by enzyme amplified sensitivity immunoassay. TLR4 and TLR2 polymorphisms were determined using polymerase chain reaction - restriction fragment length polymorphism technique. RESULTS: TNF-alpha and sTNFR2 levels in obese children were significantly (P<.01) higher than controls. Significant (P<.05), positive, linear correlations were observed between TNF-alpha, sTNFR2 levels, and BMI. Patients carrying the mutant alleles of TLR4 (299G and 399I) had lower TNF-alpha and sTNFR2 levels compared to patients carrying wild-type alleles (299D and 399T) (TNF-alpha 4.4+/-0.7 pg/mL vs 5.5+/-0.9 pg/mL; sTNFR2 2.9+/-1.2 ng/mL vs 4.4+/-1.1 ng/mL; P<.001). The R753Q polymorphism of TLR2 was not associated with altered cytokine levels, and the R677W polymorphism was not detected in the sample population. CONCLUSIONS: Serum levels of TNF-alpha and its soluble receptors are elevated and associated with increasing BMI values in obese children. Serum cytokine levels, as modifying factors of insulin resistance, may be affected by TLR4 polymorphisms in obese children.

Low complement C4B gene copy number predicts short-term mortality after acute myocardial infarction.

BACKGROUND AND OBJECTIVES: Some recent data indicate that risk of death after acute coronary syndrome is under genetic control. Previously, we found that the C4B*Q0 genotype (low copy number of the C4B gene that encodes the fourth component of complement) is strongly associated with morbidity and mortality of cardiovascular diseases (CVD). The +252 G allele of the lymphotoxin-alpha (LTA) gene encoded close to the C4B gene was also reported to be related to CVD-related mortality in an Oriental population. METHODS: The relationship between the copy number of the genes encoding the fourth component of complement (C4A and C4B) and LTA 252 single-nucleotide polymorphism (SNP) on the one hand and mortality after acute myocardial infarction (AMI) was studied in 142 Icelandic patients. The number of the C4A and C4B genes was determined in genomic DNA samples by a newly developed real-time PCR-based method; lymphotoxin-alpha (LTA) +252 A>G polymorphism was determined by PCR-restriction fragment length polymorphism analysis. RESULTS: The C4B*Q0 genotype was found to be strongly associated with 1-year mortality, with a hazard ratio of 3.50 (1.38-8.87) (P = 0.008) (adjusted Cox regression analysis). This association was, however, restricted to ever-smoking patients. By contrast, neither C4A gene copy numbers nor LTA 252 SNP did confer increased risk of mortality after AMI. CONCLUSIONS: This observation indicates that low C4B copy number is a strong risk factor for short-term mortality after AMI in smoking Icelandic patients, whereas LTA 252 G allele is not a risk factor in Caucasian population.

Polymorphisms of TNF-alpha and LT-alpha genes in multiple myeloma.

Allelic distribution of -308 G>A (TNF 1/2) polymorphism of the TNF-alpha, and the +252 A>G promoter polymorphism of the LT-alpha gene, the 1267 A>G polymorphism of the HSP70-2 gene as well as the -429 T>C promoter polymorphism of the RAGE gene were tested in 94 MM cases and 141 controls. Significantly less MM patients than controls carried the TNF2 allele (p=0.018) and the TNF2-LTA 252G haplotype (p=0.025). The difference was, however, restricted to the females, as well as the relatively young (<69 years) subjects. By contrast, we did not find differences with the other SNPs tested.

Toll-like receptor 4 gene polymorphisms and preeclampsia: lack of association in a Caucasian population.

Preeclampsia is a multifactorial disorder with genetic and environmental components. As Toll-like receptor 4 (TLR4) has an essential role in innate immune response, which is exaggeratedly activated in preeclampsia, our aim was to investigate whether two single nucleotide polymorphisms (SNPs) of the TLR4 gene--Asp299Gly (A896G) and Thr399Ile (C1196T)--are associated with preeclampsia in a Caucasian population from Hungary. In a case-control study, we analyzed blood samples from 180 preeclamptic patients and 172 normotensive, healthy pregnant women with the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. The linkage disequilibrium (LD) profile of the TLR4 gene was investigated and tag SNPs were identified using data from the International HapMap Project. There were no significant differences in the genotype and allele frequencies of Asp299Gly and Thr399Ile polymorphisms between the two study groups. Additionally, no significant difference was found in the distribution of the estimated haplotypes created by the two polymorphisms between the preeclamptic and the control group. Furthermore, no significant differences were detected in the genotype, allele and haplotype frequencies of Asp299Gly and Thr399Ile TLR4 SNPs between patients with mild and severe preeclampsia, between patients with late and early onset of the disease, or between preeclamptic patients with and without fetal growth restriction. In conclusion, we did not find an association between TLR4 Asp299Gly and Thr399Ile gene polymorphisms and preeclampsia. As the Thr399Ile polymorphism is a highly informative tag SNP of the TLR4 gene, our results suggest that variations in this genomic region are not associated with preeclampsia. Nevertheless, further studies are required with determination of fetal TLR4 genotypes to explore the role of TLR4 gene polymorphisms in the risk of preeclampsia, especially in ethnically different populations.

Association between tumor necrosis factor (TNF)-alpha G-308A gene polymorphism and preeclampsia complicated by severe fetal growth restriction.

BACKGROUND: Preeclampsia and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome are multifactorial disorders with genetic and environmental components. Given that the tumor necrosis factor (TNF)-alpha G-308A single nucleotide polymorphism (SNP) affects TNF-alpha gene transcription and that preeclampsia and HELLP syndrome are characterized by a shift towards a Th1-type maternal immune response with increased TNF-alpha production, the aim of the current study was to investigate whether this SNP is associated with preeclampsia and HELLP syndrome in a Caucasian population from Hungary. Additionally, we aimed to examine whether TNF-alpha G-308A polymorphism can influence the risk for fetal growth restriction in preeclamptic patients, which issue none of the earlier studies dealt with. METHODS: In a case-control study, we analyzed blood samples from 140 preeclamptic patients, 69 patients with HELLP syndrome and 144 normotensive, healthy pregnant women using the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. We performed also a meta-analysis with our results and those of 8 previously published studies. RESULTS: There were no significant differences in the genotype and allele frequencies of the TNF-alpha G-308A polymorphism between preeclamptic patients and normotensive, healthy pregnant women. However, the mutant (TNF2 or A) allele occurred significantly more frequently in preeclamptic patients with IUGR than in those without IUGR (18.5% versus 7.1%, p=0.003). In addition, the frequency of the mutant allele carriers was significantly higher among preeclamptic patients with IUGR compared to those without IUGR (30.6% versus 12.8%, p=0.010). The mutant allele carriers were found to have an increased risk of severe IUGR-complicated preeclampsia, which was independent of maternal age, prepregnancy BMI and primiparity (odds ratio (OR): 2.89, 95% confidence interval (CI): 1.16-7.22, p=0.023; adjusted OR: 2.78, 95% CI: 1.04-7.45, p=0.042). Nevertheless, no significant differences were detected in the genotype and allele frequencies of the TNF-alpha G-308A polymorphism between patients with HELLP syndrome and control subjects. In the meta-analysis, no association was observed between this SNP and preeclampsia (summary OR: 0.956, 95% CI: 0.693-1.319). CONCLUSIONS: Although the meta-analysis demonstrated a lack of an overall association between TNF-alpha G-308A polymorphism and preeclampsia, our results suggest a role of this SNP in the risk of severe IUGR-complicated preeclampsia. However, further studies are required with a larger sample size to confirm our findings.

The HLA 8.1 ancestral haplotype is strongly linked to the C allele of -429T>C promoter polymorphism of receptor of the advanced glycation endproduct (RAGE) gene. Haplotype-independent association of the -429C allele with high hemoglobinA1C levels in diabetic patients.

Previously we reported on strong linkage disequilibrium (LD) between the mono-S-C4B-RCCX module (mono-S) and the TNF2 allele (both known constituents of the 8.1 ancestral haplotype (8.1 AH)) in two Caucasian populations. The gene for the receptor of advanced glycation endproducts (RAGE) is encoded between the RCCX module and the HLA class II genes in the central MHC region. In order to assess the relationship between the promoter polymorphisms of the RAGE gene and the 8.1 AH, we performed a family study in eight informative families affected with type 1 diabetes mellitus; haplotypes of a RAGE promoter SNP (-429T>C) with the HLA-DQ2, -DR-3(17) and TNF2 alleles, as well as the mono-S genotype were determined. A similar analysis was performed in 82 unrelated patients with type 1 diabetes mellitus, and in unrelated healthy individuals of three different Caucasian populations (Hungarians, Ohioian females, Icelandics). In the diabetic patients clinical correlations were also investigated. Out of the 32 paternal and maternal chromosome 6 from the eight families, 15 different MHC haplotypes were found. Haplotypes containing at least three of the known constituents of the 8.1 AH (HLA-DQ2, -DR17, mono-S, TNF2) were always linked to the RAGE -429C allele. The RAGE -429C allele exhibited highly significant (p<0.0001) LD coefficients to known constituents of the 8.1 AH both in healthy persons and patients with type 1 diabetes. In the group of patients with diabetes we found significantly (p=0.013) higher maximal hemoglobinA1C concentration in the carriers of the RAGE -429C allele, this trait, however was not linked to the 8.1 AH. Our present findings indicate that the RAGE -429C allele can be considered as a candidate member of the 8.1 AH. The results also reveal a spectrum of recombinant MHC haplotypes in addition to the conserved ancestral haplotypes.

Estrogen receptor alpha (ESR1) PvuII and XbaI gene polymorphisms in ischemic stroke in a Hungarian population.

BACKGROUND: Ischemic stroke is a multifactorial disorder with genetic and environmental components. The aim of our study was to investigate whether two polymorphisms of the estrogen receptor alpha (ESR1) gene (ESR1 c.454-397T>C and c.454-351A>G) are associated with ischemic stroke in a Caucasian population from Hungary. METHODS: One hundred and ninety-eight patients with ischemic stroke and 180 control subjects were enrolled in this case-control study. Ischemic stroke subtypes were categorized according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification as large-artery atherosclerosis, small-artery occlusion, cardioembolism or stroke of other determined etiology. The ESR1 PvuII and XbaI genotypes were determined using the PCR-RFLP method. RESULTS: There were no significant differences in the genotype, allele and haplotype frequencies of PvuII and XbaI polymorphisms between the group of patients with ischemic stroke and the control group. Furthermore, ESR1 PvuII and XbaI genotypes, alleles and haplotypes were not associated with any subtype of ischemic stroke. CONCLUSIONS: We did not observe an association between ESR1 PvuII and XbaI gene polymorphisms and ischemic stroke or any subtype of ischemic stroke. However, further studies are needed to explore the complex interaction between environmental factors and ESR1 gene polymorphisms in the risk of ischemic stroke, particularly in ethnically different populations.

Lipid, haemostatic and inflammatory variables in relation to the estrogen receptor alpha (ESR1) PvuII and XbaI gene polymorphisms.

BACKGROUND: Estrogen is known to affect lipoprotein metabolism, the haemostatic system and inflammatory markers. Our aim was to determine whether estrogen receptor alpha (ESR1) PvuII and XbaI gene polymorphisms can influence lipid, haemostatic and inflammatory variables in healthy Caucasian women and men of reproductive age. METHODS: 58 healthy women (aged between 18 and 45 years) and 55 healthy men (aged between 21 and 45 years) of reproductive age were enrolled in our study. FSH levels, lipid (total cholesterol, triglyceride, HDL cholesterol, lipoprotein(a), apo A-I, apo B), haemostatic (prothrombin time, activated partial thromboplastin time (aPTT), thrombin time, fibrinogen, factor V, VII, VIII, protein C, protein S, antithrombin III) and inflammatory (CRP) variables were measured on autoanalyzers using commercially available kits. Serum VLDL and LDL cholesterol concentrations were calculated with the equation of Friedewald. The ESR1 PvuII and XbaI genotypes were determined with PCR-RFLP method. RESULTS: In the total group, the ESR1 XbaI GG genotype carriers had significantly higher serum lipoprotein(a) concentrations than the AA or AG genotype carriers. Serum total cholesterol concentrations were significantly higher in healthy women with the PvuII CC genotype than in those with the TT or TC genotypes, whereas healthy women with the GG genotype of the ESR1 XbaI polymorphism had significantly higher serum total cholesterol and LDL cholesterol levels compared to those with the AA or AG genotypes. No other effects of the ESR1 PvuII and XbaI polymorphisms were found on the investigated lipid, haemostatic and inflammatory variables either in the total group or in women and men separately. CONCLUSIONS: The ESR1 PvuII and XbaI gene polymorphisms seem to affect lipoprotein metabolism in healthy subjects of peak reproductive age. However, further studies are needed to determine the molecular mechanisms by which the two polymorphisms could influence serum lipid levels.

Claudin-1 and claudin-2 differentiate fetal and embryonal components in human hepatoblastoma.

Claudins (CLDNs), a family of transmembrane proteins, are major constituents of tight junctions (TJs). They have been shown to be differentially regulated in malignant tumors and play a role in carcinogenesis and progression. We aimed to explain the molecular mechanism underlying the main epithelial components of hepatoblastomas (HBs) based on the composition of TJs. Fourteen formalin-fixed, paraffin-embedded surgical resection specimens were analyzed by immunohistochemistry for CLDN-1, -2, -3, -4, -7; proliferating cell nuclear antigen (PCNA); Ki-67; beta-catenin; cytokeratin-7 (CK-7); and hepatocyte-specific antigen; messenger RNA was isolated for real-time reverse transcriptase polymerase chain reaction analysis of the CLDNs from dissected fetal and embryonal cell types. Significantly increased protein and messenger RNA expression of CLDN-1 and -2 was detected in the fetal compared with the embryonal component. Both cell types displayed negative or weak immunostainings for CLDN-3, -4, and -7. Hepatocyte-specific antigen was dominantly expressed in the fetal component. PCNA and Ki-67 labeling indices were significantly higher in embryonal compared with fetal cells. beta-catenin cytoplasmic/nuclear immunoreaction was frequent, although not showing significant differences between fetal and embryonal cells. Mutational analysis of beta-catenin detected mutation in two cases. Our results suggest that increased expression of CLDN-1 and -2 characterizes the more differentiated fetal component in HBs and is a reliable marker for differentiating fetal and embryonal cell types in HBs. The results proved that the embryonal and fetal components of HBs differ in such important feature as the protein composition of TJs. The expression of CLDN-1 and -2 is inversely correlated with cell proliferation. The more aggressive, rapidly proliferating embryonal phenotype is associated with the decrease/loss of CLDN-1 and -2. However, there are no data indicating association with the nuclear translocation of beta-catenin.

Association between interleukin-6 polymorphism and age-at-onset of type 1 diabetes. Epistatic influences of the tumor necrosis factor-alpha and interleukin-1beta polymorphisms.

Multiple immune mediators have been mentioned as playing a role in the pathomechanism of type1 DM. Interleukin (IL)-1beta, and tumor necrosis factor (TNF)-alpha play a central role in the autoimmune destruction of pancreatic beta-cells, whereas IL-6 inhibits TNF-alpha secretion, and may have some protecting effects. In our study, we aimed to investigate the association between these three cytokines' single nucleotide polymorphisms (IL-6 gene G(-174)C, TNF-alpha gene G(-308)A and IL-1beta gene C(3954)T polymorphisms) and age-at-onset of type 1 diabetes mellitus (T1DM) in 165 diabetic children (median age: 17 years). Polymorphisms were determined using the PCR-RFLP method. We found that the age-at-onset of T1DM was significantly different in patients with a different IL-6 genotype (median age-at-onset of T1DM was: 8, 6 and 4.5 years in children with the (-174)GG, GC and CC genotypes, respectively; p < 0.01). Adjusted for TNF-alpha and IL-1beta polymorphisms, patients with a IL-6 (-174)CC genotype have a 3.0-fold (95% CI: 1.2-7.1) increased risk of developing diabetes before the age of 6 years than (-174)G allele carrier patients. However, we found this association to be present only in patients who carried the TNF-alpha (-308)A or IL-1beta (3954)T allele, i.e. in patients with high TNF-alpha and high IL-1beta producer genotypes. We suppose that in the case of high TNF-alpha and IL-1beta producer genotypes, elevated proinflammatory cytokine levels result in a higher production of IL-6 in (-174)G allele carrier patients. This elevated IL-6 level may have a protective effect against the development of T1DM and may delay the destruction of pancreatic beta-cells.

[Pancreas pseudocyst or metastasis?]. / Pancreas-pseudocysta vagy metasztázis?

The authors review a case of a 24-year-old male patient hospitalised for repeated acute abdominal symptoms. His medical history included no diseases worth of mentioning. By imaging techniques (abdominal US and CT scan) a cystic lesion, measuring 40 x 35 x 30 mm in diameter was found, and was diagnosed as pseudocyst in the region of the tail of the pancreas. Jejunal feeding was introduced. The lesion did not improve and the second CT scan suggested a suspicion of pancreatic cystadenoma. Three months after first presentation the surgical resection was performed. The tumour, however, was found independent of the pancreas (90 x 80 x 50 mm). Both histologically and immunohistochemically the lesion proved to be the metastasis of a germ cell (yolk-sac) tumour. Following the morphological diagnosis, detailed urological and medical check up was performed. A previously nonpalpable small tumour was found in the left testis which was radically resected. The testicular tumour measuring 9 x 9 x 5 mm in diameter was diagnosed as embryonal carcinoma. Later on the patient underwent chemotherapy. He has been undergoing close oncological followup. Clinically, he is disease free. Authors emphasize the importance of imaging techniques and fine needle aspiration cytology in the case of retroperitoneal masses in young males. The possibility of a metastasis, especially of germ cell origin, should be excluded (not only by physical examination, but by ultrasound of testis also) in case of retroperitoneal cystic tumours even with unusual morphology.

Relationship between complement components C4A and C4B diversities and two TNFA promoter polymorphisms in two healthy Caucasian populations.

The RP-C4-CYP21-TNX (RCCX) modules and the tumor necrosis factor (TNF) gene cluster are probably the most polymorphic genomic regions in the human central major histocompatibility complex (MHC). Using definitive methods for genotypic and phenotypic analyses of complement components C4A and C4B, determination of the RCCX length variants, and SSP-PCR/RFLP analyses of TNFA promoter polymorphisms at positions -308 and -238, we studied the complex relationships between the C4 and TNFA polymorphisms in two normal Caucasian populations. The patterns of the RCCX modular structures and the allelic frequency of -308A TNFA (TNF2) were similar between the Budapest (n = 125) and the Ohio (n = 80) Caucasians. However, the frequency of the -238A allele was significantly higher in the Ohio (11.3%) than in the Budapest (1.6%) study population (p < 0.0001). Marked features were found in the RCCX length variants in the TNF2 carriers and noncarriers. Strong associations were found between the C4AQ0 B1 haplotype from the monomodular short (mono-S) RCCX structure and the TNF2 allele, and between the C4A6 B1 haplotype from the bimodular long-short (LS) structure of the RCCX and the TNFA -238A allele. However, 36%-46% of the TNF2 carriers did not associate with a mono-S in both study cohorts, and 57.1% of the TNFA -238A carriers in Ohio did not associate with C4A6, which has a defective complement C5 convertase activity. The carriers of TNF2 allele had significantly lower C4A serum concentration (0.17 +/- 0.08 g/l) than noncarriers (0.23 +/- 0.09 g/l) (p < 0.001). The lowest C4A serum levels were found in TNF2 carriers with mono-S structures (0.14 +/- 0.06 g/l). In essence, our results demonstrated the heterogeneities of the TNFA promoter polymorphisms, and the linkage disequilibrium of TNFA -308A and -238A alleles with complement C4A deficiency and impaired C4A protein function, respectively.

Correlation of maternal serum fetuin/alpha2-HS-glycoprotein concentration with maternal insulin resistance and anthropometric parameters of neonates in normal pregnancy and gestational diabetes.

OBJECTIVE: Human fetuin/alpha(2)-HS-glycoprotein (AHSG) is a 49 kDa serum and tissue protein which is a natural inhibitor of insulin receptor signaling. We investigated serum AHSG levels during pregnancy and whether the protein is involved in insulin resistance observed in healthy pregnant women and patients with gestational diabetes. DESIGN: One hundred and four healthy pregnant women and 23 of their neonates, 30 patients with gestational diabetes and their neonates and 30 healthy age-matched non-pregnant females as a control group were investigated in a case-control cross-sectional study. METHODS: Serum AHSG was determined by radial immunodiffusion. RESULTS: We observed an increase of serum AHSG concentration in the second and third trimesters. Gestational diabetes patients had significantly higher AHSG levels than healthy pregnant women and non-pregnant controls. There was a highly significant positive correlation between serum AHSG concentration and indirect parameters of insulin resistance, i.e. tumor necrosis factor-alpha (TNF-alpha), leptin, C-peptide and C-peptide/blood glucose ratio. There was also a negative correlation between maternal AHSG, TNF-alpha, leptin levels and head circumference, body length and body weight of newborns. CONCLUSION: AHSG, TNF-alpha and leptin may contribute to insulin resistance during normal pregnancy and gestational diabetes. AHSG along with these cytokines may also negatively regulate neonatal skeletal development.