A polymorphism within interleukin-21 receptor (IL21R) confers risk for systemic lupus erythematosus and is associated with malar rash in lupus patients (49.17)

Interleukin (IL) 21 is a member of the type I cytokine superfamily that exerts a variety of effects on the immune system including B cell activation, plasma cell differentiation, and immunoglobulin production. The IL21 receptor (IL21R) is expressed on B cells, T cells, NK cells, and monocyte-derived dendritic cells. The expression of IL21R is reduced in B cells from lupus patients, while IL21 serum levels are increased in both lupus patients and some lupus-murine models. We recently reported that polymorphisms within the IL21 gene are associated with increased susceptibility to lupus. Herein, we genotyped SNPs in the IL21R gene located on chromosome 16p11. We identify and confirm the association between rs3093301 and lupus in two independent European-derived and Hispanic cohorts (p=7.2X10-5). In addition, the presence of the homozygous risk genotype in rs3093301 (A/A) was associated with the development of malar rash in the European-derived female lupus patients (OR=2.83, 95% CI=1.56-5.13, p=0.00045).

Genome-wide linkage analysis of ADHD using high-density SNP arrays: novel loci at 5q13.1 and 14q12

Previous genome-wide linkage studies applied the affected sib-pair design; one investigated extended pedigrees of a genetic isolate. Here, results of a genome-wide high-density linkage scan of attention-deficit/hyperactivity disorder (ADHD) using an array-based genotyping of approximately 50 K single nucleotide polymorphism (SNPs) markers are presented. We investigated eight extended pedigrees of German origin that were non-related, not part of a genetic isolate and ascertained on the basis of clinical referral. Two parametric analyses maximizing LOD scores (MOD) and a non-parametric analysis for both a broad and a narrow phenotype approach were conducted. Novel linkage loci across all families were detected at 2q35, 5q13.1, 6q22-23 and 14q12, within individual families at 18q11.2-12.3. Further linkage regions at 7q21.11, 9q22 and 16q24.1 in all families, and at 1q25.1, 1q25.3, 9q31.1-33.1, 9q33, 12p13.33, 15q11.2-13.3 and 16p12.3-12.2 in individual families replicate previous findings. High-resolution linkage mapping points to several novel candidate genes characterized by dense expression in the brain and potential impact on disorder-relevant synaptic transmission. Our study provides further evidence for common gene effects throughout different populations despite the complex multifactorial etiology of ADHD.

The effect of counter-ions on the supramolecular arrangement of (benzonitrile)[1,2-bis(diphenylphosphino)ethane](η5-cyclopentadienyl)iron(II) cations

The title compound, [1,2-bis(diphenylphosphino)ethane](eta5-cyclopentadienyl)(4-nitrobenzonitrile)iron(II) iodide, [Fe(eta5-C5H5)(C7H4N2O2)(C26H4P2)]I, crystallizes in the non-centrosymmetric space group Cc, which is a promising result for obtaining quadratic non-linear optical properties. However, the packing shows that the iodide counter-ion promotes the cancellation of almost all the dipoles, resulting in a supramolecular motif of cationic chains aligned in opposite directions making an angle of 35.2 degrees. The use of PF6- as counter-ion induces the crystallization of the complex in a centrosymmetric space group. These results show that the introduction of different counter-ions, of different size and geometry, allows specific and directional intermolecular interactions that can determine the formation of a particular type of crystal packing.

[Incidence and risk factors of HCV infection in a cohort of intravenous drug users in the North and East of France]

BACKGROUND

In order to evaluate the incidence and risk factors of infection by hepatitis C virus (HCV) among intravenous drug users we conducted a prospective cohort study of HCV and HIV negative IVDU in the North and East of France.

METHODS

Two hundred and thirty-one IVDU who had injected drug at least once in their lifetime and were negative for anti-HCV and anti-HIV were followed-up every three months over a 12-month period. Serum anti-HCV and anti-HIV antibodies were tested at inclusion in the study and at the end of the follow-up. Data on injection practices and behaviours were collected at inclusion and at each visit, and a test for anti-HCV antibodies was performed on a saliva sample. When this proved positive, an ELISA test for serum anti-HCV antibodies was carried out.

RESULTS

Of the 231 participants included, 165 (71.4%) underwent a final HCV and HIV serum test. The incidence was nil for HIV infection and 9% (95% CI: 4.6-13.4) person-years for HCV infection. Among IVDU who injected at least once during the last 6 months HCV infection incidence was 11% (95% CI: 4.7-17.1) person-years. The multivariate analysis carried out on the inclusion data found female sex alone to be an independent predictive factor of HCV seroconversion. In a Cox proportional hazard multivariate analysis that took into account time-dependent exposures and covariates, we found that syringe and cotton sharing were, after adjusting for other covariates, the only independent predictive factors of HCV seroconversion: hazard ratio: 6.3 [corrected] (95% CI: 1.1-35.4; [corrected] p<0.05) and 16.4 (95% CI: 1.4-190.6; [corrected] p<0.05), respectively.

CONCLUSION

The transmission of the HCV virus persists among French IVDU despite an ongoing national harm reduction program. Injecting material and cotton sharing are the two major determinants of transmission in this cohort.

Effect of training and detraining on catecholamine responses to sprint exercise in adolescent girls

Training is well known to influence catecholamine responses to exercise. In women, this training effect is still not well characterized and has been studied mostly in adults. Hence, we investigated in this longitudinal study, the effects of a 6-month sprint training program followed by 5 months of detraining on plasma catecholamine responses to a sprint exercise in young female subjects. Twelve healthy adolescent girls [training group (TG), n=6; control group (CG), n=6] took part in our study. TG participated in 6 months of supervised sprint training program (3 days/week) and has no training past whereas, CG continued with it's normal activity. A 6s-sprint test was performed on a cycle ergometer before training (P1) and after training (P2) in both the groups. TG only realized a 6s-sprint test after 5 months of detraining (P3). Blood lactate concentrations (La) as well as plasma adrenaline (A) and noradrenaline (NA) concentrations were measured at rest, immediately after the warm-up and the 6s-sprint and during recovery. Peak power W peak), expressed both in absolute and relative values, were significantly increased in TG in P2 (P<0.01) but did not change in CG. After the sprint-training period, the warm-up and the 6s-sprint induced plasma A increase and the maximal A concentrations were significantly higher than in P1 and P3 for TG only (P<0.05). Plasma A did not change in CG after 6 months. In P3, W peak and maximal lactate concentrations ([La]max) were significantly greater compared to P1 and P2 in TG (P<0.05). In CG, [La]max were significantly increased in P2 (P<0.05). The present study demonstrates that 6 months of sprint training in adolescent girls induce both an increase in performances and in A responses to sprint exercise. This adrenergic adaptation disappears after 5 months of detraining whereas the gain in performance is maintained. These new data may lead to practical considerations.

Reactive sulphur species in oxidative signal transduction

Intense interest has been generated by the discovery that reactive oxygen species can function as intracellular second messengers. Reactive oxygen species have been implicated in diverse cellular processes, including growth factor signal transduction, gene expression and apoptosis. Additionally, there is evidence for proteins that are regulated by redox environment through the reversible oxidation of their cysteine residues. However, the direct reaction of reactive oxygen species with cysteine at physiological concentrations is generally a slow process, suggesting that intermediates are required to convey efficiently the oxidative stimulus. Here, we discuss the evidence that DSOs (disulphide-S-oxides) are formed from glutathione under oxidizing conditions and specifically modulate the redox status of thiols, indicating the existence of specialized cellular oxidative pathways. DSO inactivated glyceraldehyde 3-phosphate and alcohol dehydrogenases and released zinc from metallothionein and a zinc finger domain. In contrast, equivalent concentrations of H(2)O(2) showed minimal effect. The antioxidants ascorbate, NADH, trolox and melatonin were unable to quench DSO-induced oxidation. These findings support the paradigm of oxidative signal transduction and provide a general pathway whereby reactive oxygen species can convert thiols into disulphides.

Incidence and risk factors of HCV and HIV infections in a cohort of intravenous drug users in the North and East of France

In order to evaluate the incidence and risk factors of infection by hepatitis C virus (HCV) among injecting drug users (IDUs), we conducted a prospective cohort study of HCV- and human immunodeficiency virus (HIV)-negative IDUs in the North and East of France. A total of 231 HCV and HIV IDUs who had injected drugs at least once in their lifetime were followed up every 3 months over a 12-month period. Serum anti-HCV and anti-HIV were tested at inclusion in the study and at the end of the follow-up. Data on injecting practices were collected at inclusion and at each visit. Of the 231 participants included, 165 (71.4%) underwent a final HCV and HIV serum test. The incidence was nil for HIV infection and 9/100 person-years (95% CI 4.6-13.4) for HCV infection. In a multivariable analysis, we found that syringe and cotton sharing were the only independent predictive factors of HCV seroconversion.

Cholecystokinin- and cholecystokinin-B-receptor gene polymorphisms in panic disorder

Panic disorder like other neuropsychiatric disorders is believed to be caused by multiple psychosocial and biological factors. Several lines of evidence point to a role for the peptide neurotransmitter cholecystokinin in the pathogenesis of panic disorder. We therefore determined the allele and genotype frequencies of a single nucleotide polymorphism in the CCK gene (-36C>T) and one CT repeat polymorphism in the CCK-B-receptor gene in a German panic disorder sample (n = 115 for CCK gene polymorphism, n = 111 for CCK-B-receptor polymorphism) and compared them with gender and age matched controls. The length of the polymorphic CT repeat alleles varies between 146 bp and 180 bp. We first analysed the results by a permutation test which provided evidence for heterogeneity between patients and controls (p=0.002). We then analysed the data as a di-allelic polymorphism with a short (146-162bp) and a long (164-180bp) allele and as a tetra-allelic polymorphism with 4 alleles (146-154bp, 156-162bp, 164-170bp, 172-180bp). In the di-allelic analysis as well as in the tetra-allelic analysis there was an excess of the longer allele (p = 0.001) or the two longer alleles (p = 0.041) respectively in patients with panic disorder. No difference between groups was observed for the -36C > T polymorphism. Our findings are consistent with the notion that genetic variation in the CCK neurotransmitter system contributes to the pathogenesis of panic disorder.