Association of TNFAIP3 and TNFRSF1A variation with multiple sclerosis in a German case-control cohort.

Variations in two genes of the tumour necrosis factor (TNF) alpha pathway have been implicated in the pathogenesis of autoimmune diseases: polymorphisms in the TNFRSF1A gene, encoding TNF receptor 1, showed significant association with MS in genomewide association scans, and variation in or near the TNFAIP3 gene, coding for a negative regulator of NFkB, was associated with MS, systemic lupus erythematosus, diabetes and rheumatoid arthritis. This study aimed at investigating association of MS with variation in the TNFRSF1A gene as well as in the TNFAIP3 gene region in an independent German case-control cohort. Four hundred and ninety-seven unrelated patients with MS and 878 healthy controls were genotyped with restriction enzyme digestion or TaqMan assays for three polymorphisms in the TNFRSF1A gene and seven in the region of the TNFAIP3 gene. Allele, genotype and haplotype frequencies were compared between cases and controls by chi-square testing. We found significant association of rs10499194, located in the intergenic region upstream of TNFAIP3, with MS (pc = 3.4 × 10(-4) ). Further, the intronic SNP rs1800693 in TNFRSF1A showed moderate association (pc = 0.033) with MS. In conclusion, evidence is accumulating that polymorphisms in both TNFAIP3 and TNFRSF1A genes play a role in MS pathogenesis. Additional studies are warranted to further elucidate the role of TNF pathway variation for MS development.

Genetics of toll like receptor 9 in ANCA associated vasculitides.

OBJECTIVES: To investigate the contribution of genetic polymorphisms of toll like receptor (TLR) 9 and related genes on the susceptibility and clinical manifestation of anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitides (AAV). METHODS: Four single nucleotide polymorphisms (SNPs) in TLR9 were genotyped in 863 German AAV cases and 1344 healthy controls. Significant results were replicated in a cohort of 426 Dutch and British AAV cases. 11 polymorphisms in TLR9 related genes were studied concomitantly. RESULTS: A strong association of TLR9 genotypes and haplotypes with granulomatosis with polyangiitis was observed as well as a contrariwise association with microscopic polyangiitis. The association was confirmed when cases were compared according to ANCA status rather than to clinical entity. This was partly replicated in the second cohort leading to a striking overall difference in TLR9 allele/haplotype frequencies between proteinase 3 (PR3) ANCA+ and myeloperoxidase (MPO) ANCA+ cases (p=0.00000398, pc=0.000016, OR 1.68 (95% CI 1.35 to 2.1) for rs352140; p=0.000011, pc=0.000044, OR 1.64 (95% CI 1.31 to 2.04) for a 3-SNP haplotype). No significant association or epistatic effect was detected for TLR9 related genes: interleukin 6, interleukin 23 receptor, myeloid differentiation primary response 88, TNF receptor-associated factor 6, interleukin-1 receptor-associated kinase 4, discs large homolog 5 and nucleotide-binding oligomerisation domain containing 2. CONCLUSIONS: We provide further evidence that PR3-ANCA+ AAV differs genetically from MPO-ANCA+ AAV. TLR9 signalling may be involved in disease pathology, favouring models of infectious agents triggering AAV development.

Changes in the anaerobic threshold in an annual cycle of sport training of young soccer players.

The aim of the study was to assess changes in the anaerobic threshold of young soccer players in an annual training cycle. A group of highly trained 15-18 year old players of KKS Lech Poznan were tested. The tests included an annual training macrocycle, and its individual stages resulted from the time structure of the sports training. In order to assess the level of exercise capacities of the players, a field exercise test of increasing intensity was carried out on a soccer pitch. The test made it possible to determine the 4 millimolar lactate threshold (T LA 4 mmol · l(-1)) on the basis of the lactate concentration in blood [LA], to establish the threshold running speed and the threshold heart rate [HR]. The threshold running speed at the level of the 4 millimolar lactate threshold was established using the two-point form of the equation of a straight line. The obtained indicators of the threshold running speed allowed for precise establishment of effort intensity used in individual training in developing aerobic endurance. In order to test the significance of differences in mean values between four dates of tests, a non-parametric Friedman ANOVA test was used. The significance of differences between consecutive dates of tests was determined using a post-hoc Friedman ANOVA test. The tests showed significant differences in values of selected indicators determined at the anaerobic threshold in various stages of an annual training cycle of young soccer players. The most beneficial changes in terms of the threshold running speed were noted on the fourth date of tests, when the participants had the highest values of 4.01 m · s(-1) for older juniors, and 3.80 m · s(-1) for younger juniors. This may be indicative of effective application of an individualized programme of training loads and of good preparation of teams for competition in terms of players' aerobic endurance.

Breast phantom for comparison X-ray and polarimetric optical tomography imaging.

Breast phantom made as combination of paraffin and INTRALIPID™ was tested by use of X-ray classical computed tomography and polarimetric optical tomography. The INTRALIPID™ is a liquid commonly used for simulation breast tissues optical properties but it is useless as X-ray phantom. During our tests we have observed that X-ray tomography allows to recognize a proper placement of INTRALIPID™ inclusions inside paraffin medium but we cannot distinguish density of INTRALIPID™ within each inclusions. On the other hand the polarimetric optical tomography allows to distinguish density of INTRALIPID™ (0%, 10%, 20%) in inclusions but with relatively low accuracy of their placement.

ANCA-associated vasculitis is linked to carriage of the Z allele of α1 antitrypsin and its polymers.

BACKGROUND: Small studies have linked α1 antitrypsin (α1AT) deficiency to patients with antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). OBJECTIVE: To test the validity and the mechanism of this association between α1AT and AAV. METHODS: The distribution of α1AT deficiency alleles Z and S was compared between 856 White Europeans with AAV and 1505 geographic and ethnically matched healthy controls. Genotyping was performed by allelic discrimination assay. RESULTS: were compared between cases and controls using χ(2) tests. The serum and renal biopsies for α1AT polymers were compared using the polymer-specific 2C1 antibody. The role of α1AT polymers in promoting inflammation was investigated by examining their ability to prime neutrophils for ANCA activation as assessed by CD62L shedding, superoxide production and myeloperoxidase degranulation. Results The Z but not the S allele was over-represented in the patients compared with controls (HR=2.25, 95% CI 1.60 to 3.19). Higher concentrations of polymers of α1AT were detected in serum from patients carrying the Z allele than in those not carrying the Z allele (median (IQR) 1.40 (0.91-3.32) mg/dl vs 0.17 (0.06-0.28) mg/dl, p<0.001); polymers of α1AT were also seen in the renal biopsy of a patient with vasculitic glomerulonephritis. Polymers of α1AT primed neutrophils with CD62L shedding and increased superoxide production following ANCA activation. Carriage of the Z allele was not associated with disease severity, survival or relapse. CONCLUSIONS: The Z but not the S deficiency allele is associated with AAV. Polymers of α1AT are present in the serum and glomeruli of at least some patients with the Z allele, which may promote inflammation through priming of neutrophils.

[The genetics of vasculitides]. / Genetischer Hintergrund der Vaskulitiden.

Genetic association studies have been of great value in the past by contributing to the understanding of pathophysiological mechanisms of chronic inflammatory and autoimmune diseases. Many genetic risk factors have been identified which confer susceptibility for one or several (autoimmune) disease(s). Using a candidate-gene approach, the first genetic risk factors and polymorphisms of vasculitides have been identified. Due to the rarity of autoimmune vasculitides often only small sample numbers have been generated and analysed, leading to inconsistent results. Furthermore, differences in ethnic background may complicate analysis. Only few of the detected risk factors have been reliably replicated in larger cohorts, such as the association of the PTPN22*620W allele with WG and MPA, the deficiency allele Pi*Z of the alpha1 antitrypsin gene and the HLA-DPB*04041 allele with WG and the HLA-DRB3/DRB4 with CSS. Genome-wide association studies (GWAS) offer the advantage of screening the whole genome for risk factors rather than relying on disease models postulated by the investigator; however, they require even larger sample sizes. Initial results from GWA studies are available for Behçet's disease and Kawasaki syndrome, which identified new genetic associations but require replication, especially since some of the identified risk factors could not be linked to pathophysiological pathways to date.

Dynamics of two semiconductor lasers coupled by a passive resonator.

The stability of two semiconductor lasers that are spatially separated by a passive resonator is analyzed using the composite-cavity mode approach. We study the nonlinear interactions of three composite-cavity modes and identify regions of in-phase and out-of-phase laser locking in the parameter plane of the transmission coefficients of the coupling mirrors and the laser length difference. Bifurcation analysis shows that the structure of the locking regions strongly depends on (i) the length of the passive resonator and (ii) the amount of amplitude-phase coupling of the laser field. Specifically, we find a single locking region when the passive resonator and the lasers have comparable lengths and up to three separate locking regions when the passive resonator is much shorter than the lasers. Furthermore, we use the recently developed 0-1 test for chaos to uncover intricate regions of chaotic dynamics that shrink in size and eventually disappear as the passive resonator length becomes comparable to the laser length.

Locking behavior of three coupled laser oscillators.

Single-frequency operation or locking in a lateral array of three laser oscillators is studied within the composite-cavity-mode approach. We compute the regions of stable locking, which have a nontrivial shape in the plane of coupling strength versus frequency detuning. The locking regions depend drastically on the amount of amplitude-phase coupling of the lasing field that is quantified by the alpha parameter. For small alpha, locking is possible for arbitrary coupling, but only if the middle laser has sufficient frequency detuning from the two outer lasers. In contrast, for larger alpha, locking is only possible for weak to moderate coupling, provided that all three lasers have similar frequencies.

Novel association of the CD226 (DNAM-1) Gly307Ser polymorphism in Wegener's granulomatosis and confirmation for multiple sclerosis in German patients.

Recently, there has been increasing evidence that a non-synonymous exchange (Gly307Ser) in the gene for CD226 is linked to several autoimmune diseases including type 1 diabetes, multiple sclerosis (MS), rheumatoid arthritis and Grave's disease. Here we present evidence that this polymorphism also predisposes to Wegener's granulomatosis (WG), an autoimmune condition belonging to the group of ANCA (antineutrophil cytoplasmic autoantibody)-associated vasculitides. We found a significant association of the 307Ser allele in separate panels of 520 Northern German (P=0.016, odds ratio (OR)=1.20) and 122 Southern German (P=0.020, OR=1.37) WG cases compared with 1226 healthy controls. The importance of this single-nucleotide polymorphism in the etiopathology of ANCA-associated vasculitides is supported by similar effect sizes that we found in British WG cases (n=105) and German patients with Churg-Strauss syndrome (n=119), which, however, miss significance level because of the relatively small cohorts available for these rare disorders. Finally, we confirm the association with MS in a cohort of 422 German patients (P=0.011, OR=1.23).

Association of UCP2 -866 G/A polymorphism with chronic inflammatory diseases.

We reported earlier that two mitochondrial gene polymorphisms, UCP2 -866 G/A (rs659366) and mtDNA nt13708 G/A (rs28359178), are associated with multiple sclerosis (MS). Here we aim to investigate whether these functional polymorphisms contribute to other eight chronic inflammatory diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Wegener' granulomatosis (WG), Churg-Strauss syndrome (CSS), Crohn's disease (CD), ulcerative colitis (UC), primary sclerosing cholangitis (PSC) and psoriasis. Compared with individual control panels, the UCP2 -866 G/A polymorphism was associated with RA and SLE, and the mtDNA nt13708 G/A polymorphism with RA. Compared with combined controls, the UCP2 -866 G/A polymorphism was associated with SLE, WG, CD and UC. When all eight disease panels and the original MS panel were combined in a meta-analysis, the UCP2 was associated with chronic inflammatory diseases in terms of either alleles (odds ratio (OR)=0.91, 95% confidence interval (95% CI): 0.86-0.96), P=0.0003) or genotypes (OR=0.88, (95% CI: 0.82-0.95), P=0.0008), with the -866A allele associated with a decreased risk to diseases. As the -866A allele increases gene expression, our findings suggest a protective role of the UCP2 protein in chronic inflammatory diseases.

The p53 G72C and MDM2 T309G single nucleotide polymorphisms in patients with Wegener's granulomatosis.

OBJECTIVE: Wegener's granulomatosis (WG) is a rare disease with unknown aetiology, but there is evidence for a complex genetic background. The tumor suppressor p53 and its most important negative regulator, MDM2, are positioned in the centre of a pathway that eliminates damaged cells through apoptosis. Furthermore, p53 is one of the most important negative regulators of the pro-inflammatory transcription factor nuclear factor kappa b (NFkappaB). In this respect the investigation of polymorphisms in the p53-network could be a promising approach contributing susceptibility of WG and its course of disease. METHODS: A case control study with 132 patients with WG and 512 healthy blood donors was conducted to evaluate an association of p53-SNP G72C or MDM2-SNP T309G with WG. SNPs were genotyped by polymerase chain reaction (PCR) and subsequent differential enzymatic restriction. All patients showed the clinical pathological findings of WG according to the ACR classification criteria of 1990. RESULTS: The p53 G72C and MDM2 T309G polymorphisms did not show any difference between WG patients and controls. The subgroup analysis of gender differences and earlier onset of WG (younger than median age of 51 years at diagnosis) did not show any differences in allelic or genotype frequencies of p53 G72C or MDM2 T309G SNP between WG patients and the control group. CONCLUSIONS: Our study showed no association between the p53 SNP G72C and the MDM2 SNP T309G with susceptibility or course of disease in patients with WG. The data presented do not suggest that alterations in the p53-network play a key role in the pathogenesis of WG.

Functionally relevant variations of the interleukin-10 gene associated with antineutrophil cytoplasmic antibody-negative Churg-Strauss syndrome, but not with Wegener's granulomatosis.

OBJECTIVE: Wegener's granulomatosis (WG) and Churg-Strauss syndrome (CSS) belong to the heterogeneous group of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides. Current understanding of their pathogenesis and genetic background is limited. Expression levels of interleukin-10 (IL-10), a potent and pleiotropic cytokine, are largely determined by variations in the gene encoding the IL-10 precursor. This study was undertaken to determine the impact of IL10 polymorphisms on the pathogenesis of both WG and CSS in large cohorts. METHODS: Three single-nucleotide polymorphisms (SNPs) tagging the promoter haplotypes of the IL10 gene (IL10 -3575, IL10 -1082, and IL10 -592) were analyzed in 403 patients with WG and 103 patients with CSS as well as 507 matched control subjects from Germany. In addition, 3 informative SNPs in other parts of IL10 were genotyped. RESULTS: None of the markers or their haplotypes was associated with WG or any of its subgroups classified according to ANCA status, sex, or presence of further WG genetic risk factors. In contrast, the IL10 -3575/-1082/-592 TAC haplotype, part of the extended ancient haplotype IL10.2, was highly significantly associated with ANCA-negative CSS (chi2 = 19.14, P = 0.000012, corrected P = 0.0003, odds ratio 2.16, 95% confidence interval 1.52-3.06). CONCLUSION: These findings challenge those from previous studies of IL10 in WG and provide further evidence that CSS and WG have distinct genetic backgrounds. Because the IL10.2 haplotype has been correlated reproducibly with increased IL10 expression, the possible role of IL-10 in the pathogenesis of ANCA-negative CSS needs to be further elucidated.

Dynamics of two laterally coupled semiconductor lasers: strong- and weak-coupling theory.

The stability and nonlinear dynamics of two semiconductor lasers coupled side to side via evanescent waves are investigated by using three different models. In the composite-cavity model, the coupling between the lasers is accurately taken into account by calculating electric field profiles (composite-cavity modes) of the whole coupled-laser system. A bifurcation analysis of the composite-cavity model uncovers how different types of dynamics, including stationary phase-locking, periodic, quasiperiodic, and chaotic intensity oscillations, are organized. In the individual-laser model, the coupling between individual lasers is introduced phenomenologically with ad hoc coupling terms. Comparison with the composite-cavity model reveals drastic differences in the dynamics. To identify the causes of these differences, we derive a coupled-laser model with coupling terms which are consistent with the solution of the wave equation and the relevant boundary conditions. This coupled-laser model reproduces the dynamics of the composite-cavity model under weak-coupling conditions.

The Wegener's granulomatosis quantitative trait locus on chromosome 6p21.3 as characterised by tagSNP genotyping.

BACKGROUND: A genomic region on chromosome 6p21.3, including HLA-DPB1, has been linked to Wegener's granulomatosis (WG). The basis of this association is difficult to evaluate because of the complex haplotype block architecture of this region. OBJECTIVE: To identify the causative molecular genetic variation(s) using a detailed HapMap based fine-mapping approach. METHODS: 282 patients with WG and 380 healthy controls were genotyped for HLA-DPB1 as well as for 35 informative single nucleotide polymorphisms (SNPs) within the respective region. 25 of these SNPs have been selected as tagging SNPs for another 219 associated SNPs. Allele and genotype frequencies were analysed separately by contingency tables and logistic regression. Finally, the coding region of RING1 was directly sequenced in subjects who carried haplotypes that were correlated with contrasting WG risks. RESULTS: The previously reported strong association of WG with the HLA-DPB1*0401 allele was confirmed in an independent WG sample (n = 108, p(c) = 6.4 x 10(-8)). When the complete cohort (n = 282) was considered, the association remained highly significant in ANCA-positive (p(c) = 1.26 x 10(-22)), but not in ANCA-negative patients. An SNP 3' of HLA-DPB1 yielded the smallest p value and was associated with WG partly independently from the HLA-DPB1 alleles. Another informative SNP in the vicinity of RING1 showed significant WG association that was also partly independent of HLA-DPB1. RING1 sequencing, however, did not show any variation potentially predisposing to WG. CONCLUSIONS: The HLA-DPB1/RING1 region is strongly associated with WG in ANCA-positive subjects. Further analyses of potential cis regulatory sequences of candidate genes HLA-DPB1, RING1 and RXRB appear warranted.

Influence of poly(ethylene glycol) molecular mass on separation and ordering in solutions of CiEj nonionic surfactants: depletion interactions and steric effects.

We study ternary mixtures of nonionic surfactants C(i)E(j) (i = 12; j = 5, 6, 8) and poly(ethylene glycol) (PEG) in water. For sufficiently large molecular mass of PEG (M >M(sep) approximately 600), we observe a lowering of phase separation temperature with an increase in polymer concentration. The value of M(sep) is consistent with the analysis based on depletion interactions between micelles induced by polymer chains. We also demonstrate that there is another critical molecular mass of PEG (M = M* approximately 2000) necessary to induce ordering in the surfactant-rich phase. This critical molecular mass follows from two requirements: (a) PEG has to reduce the separation temperature below a temperature of hexagonal-isotropic phase transition in a binary surfactant-water mixture and (b) the PEG radius of gyration has to be larger than the size of the water channels in the hexagonal phase.

Promoter polymorphism rs3087456 in the MHC class II transactivator gene is not associated with susceptibility for selected autoimmune diseases in German patient groups.

We analysed whether the single nucleotide polymorphism (SNP) rs3087456 in the promoter of the MHC class II transactivator (MHC2TA) gene is associated with manifestation of rheumatoid arthritis, multiple sclerosis, narcolepsy and Wegener granulomatosis. The recently reported association in a northern population of the MHC2TA variation with these autoimmune diseases is not evident in the German population.

Relaxation processes in mixtures of liquid crystals and polymers near phase boundaries and during phase separation.

We present experimental studies of the relaxation of concentration fluctuations in a semidilute solution of polystyrene (PS) (30% by weight) in 4-cyano-4'-n-octyl-biphenyl (8CB) (70% by weight) using the photon correlation spectroscopy (PCS). In the homogeneous phase there are two modes of relaxation. The slow one (typical time scale is taus = 0.001 s) is due to the diffusion of polymer chains (of molecular mass 65,000) in the LC matrix (of molecular mass 290), while the fast one has the time scale of the order of tauf approximately 0.00001 s. The amplitude of the fast mode is much weaker than the one for the slow mode. Moreover it does not depend on the scattering wave vector, q. The value of the diffusion coefficient, Dc = 1/(tausq2) for the slow mode decreases with temperature according to the Arhenius law until we reach the coexistence curve. Its value close to the coexistence is Dc = 4 x 10(5) nm2/s and the activation energy in the homogeneous mixture is Ec=127 kJ/mol. If we gradually undercool the mixture below the coexistence into the metastable two-phase region without inducing the phase separation we find unexpectedly that Dc does not change with temperature even 4 degrees below the coexistence curve. The characteristic time of the fast mode does not depend on the scattering wave vector indicating that it is related to the transient gel structure. We have shown that it is possible to measure the short time relaxation of concentration fluctuations during the phase separation in the mixture. At low temperature close to the isotropic-nematic phase transition we have observed that the relaxation is well separated in time from the typical time of the domain growth. This relaxation mode is characterized by the large diffusion coefficient D = 2 x 10(8) nm2/s. The mode probably comes from the coupling between the orientational dynamics of liquid crystals and the transient gel structure of polymers.