Molar-incisor hypomineralisation prevalence in a cohort of Australian children with type 1 diabetes.

PURPOSE: Systemic diseases or drugs administered early in life may cause a disruption in amelogenesis and contribute to the qualitative defect of enamel described as molar-incisor hypomineralisation (MIH). Therefore, an increase in prevalence of MIH in children with type 1 diabetes (T1D) may be expected as this systemic disorder is commonly diagnosed in early childhood. The aim of this study was to determine the prevalence of MIH in a cohort of children with T1D and investigate diagnosis of MIH with T1D factors. METHODS: Cross-sectional study of children with T1D recruited from paediatric diabetes clinics at the Women's and Children's Hospital (South Australia). A detailed medical history, comprehensive dental and MIH examination according to the European Academy of Paediatric Dentistry (EAPD) long form classification was collected for each child. All upper and lower first permanent molars and central incisors were scored. RESULTS: A total number of 73 participants; 35 (47.95%) males were examined including 584 teeth. The mean age of the participants was 13.25 ± 2.58 years, with a mean age of diagnosis 7.75 ± 3.58 years, and a mean HbA1c of 8.5 ± 1.6%. 42 out of 73 children (54.8%) had enamel defects on at least one of the teeth examined. However, 19.2% met the criteria for MIH. Univariate and bivariate analyses were conducted but no significant associations were noted between MIH and risk factors including diabetes control (p > 0.1). CONCLUSION: There was a high prevalence of enamel defects and MIH amongst children with T1D. More research is required to establish association between T1D and MIH.

Genetic correlations of brain lesion distribution in multiple sclerosis: an exploratory study.

BACKGROUND AND PURPOSE: In MS, the total brain lesion volume and spatial distribution of lesions across the brain vary widely among individual patients. We hypothesized that spatial distribution may be partially driven by genetic predisposition, and we aimed to explore relations among candidate genes and the spatial distribution of white matter brain lesions in MS. MATERIAL AND METHODS: Genotypes of 69 SNPs in 208 patients with MS were related to the spatial distribution of T2 brain lesions. Lesions were manually outlined on MR images, and binary lesion masks were produced and registered to a common space. With Randomise software, the lesion masks were related to genotype by using a voxelwise nonparametric GLM approach, followed by clusterwise analysis. We used a DNA chip with SNPs selected from the literature on MS susceptibility, severity, and phenotypes. RESULTS: For 11 of these SNPs, 1 of the genotypes expressed significant clusters of increased or decreased lesion probability in varying, predominantly periventricular, brain regions. When we statistically controlled the voxelwise analyses for effects of total brain lesion volume, only 1 SNP remained significant: rs2227139, located within the MHC class II region. This SNP retained its periventricular cluster of significantly increased lesion probability for the heterozygote genotype. CONCLUSIONS: Heterozygosity of rs2227139 (MHC class II region) is associated with increased right frontal periventricular lesion probability (P<.01). Ten other SNPs showed associations between genotype and spatial lesion distribution that are partly explained by total lesion volume.

Coeliac disease in China, a field waiting for exploration.

BACKGROUND: no systematic studies on the prevalence of coeliac disease (CD) have been reported from China. In western populations CD is more common in patients with insulin dependent diabetes mellitus (IDDM) and in diarrhoea-predominant irritable bowel syndrome (D-IBS). We have screened patients with these conditions presenting to the outpatient department of a large hospital of "Traditional Chinese Medicine" (TCM) in Nanjing, Jiangsu province, P.R. China. METHODS: we tested sera of 78 unrelated Han Chinese patients (5 IDDM and 73 D-IBS), using ELISA serological tests for IgG anti-gliadin antibodies (IgG-AGA) and IgA anti-tissue transglutaminase antibodies (IgA-tTG). RESULTS: six out of 78 patients (7.7%) were positive for IgG-AGA (two men and four women) and two (2.6%) were positive for IgA-tTGs. One of the latter patients was negative for IgG-AGA. Besides, one patient had a dubious IgA-tTG antibody and a positive IgG-AGA. None of the six patients agreed to undergo duodenal biopsy. Two out of these six patients followed a gluten-free diet for one year. In one patient the diarrhoea ceased and his body weight increased. Another stopped losing weight. CONCLUSIONS: this study previously published as a letter in GUT (Wu J, Xia B, von Blomberg BME, Zhao C, Yang XW, Crusius JBA, Peña AS. Coeliac disease: emerging in China? Gut 2010; 59(3): 418-9) demonstrated that CD may exist in the Jiangsu province of P.R. China. The present article draws attention to the difficulties of following a standard protocol in China such as established in western countries and highlights important factors less well known in the west in relation to the development of CD in China. Wheat production became significant in China between 1600 and 1300 B.C. After the Han dynasty (500-200 B.C.), wheat was one of the main cereals in China. One the major wheat fields in China is located in the Jiangsu province where the research for this article was performed. A review of Chinese literature shows that the predominant HLA-DQ CD risk alleles and haplotypes are present in the Jiangsu province. Genetic background, food consumption, and the results of our study suggest that CD should actively be investigated in P.R. China.

Current methods to diagnose the unresponsive and complicated forms of coeliac disease.

Coeliac disease is a common disorder. Due to the protean manifestations of the disease and the often mild but indolent course, the diagnosis is often missed. The method to diagnose this in principle reversible disease after the introduction of a gluten-free diet has attracted the attention of several scientific disciplines to find the simplest and most patient-friendly test. This has resulted in a noticeable impact on the clinical practice next to a general increased awareness of its existence, its pathogenesis, its course and recent evidence of increased mortality. Amendments made in the diagnostic criteria of coeliac disease over the last half century have simplified the diagnosis. However, the aspect most relevant to the specialist in internal medicine is related to its grave consequences when the disease fails to respond to a gluten-free diet. These refractory cases may culminate in severe complications with sombre endings and malignancy. Fortunately, current technology can offer the specialist in internal medicine more facilities to diagnose the cause of the complicated cases in order to attempt to intervene in the course of disease and hopefully save these patients. We review the available tools that now exist and their indications that can be practiced in a modern clinical setting for the diagnosis of the complicated forms of this disease.

An integrated approach to the understanding of Chlamydia infections: Introduction to the 2009 update.

An integrated, multidisciplinary effort is needed to achieve a greater understanding of the immunopathogenesis of urogenital and ocular Chlamydia trachomatis infections to combat this infection successfully, to prevent long-term complications and to develop a vaccine. The contribution of molecular epidemiology and host-pathogen genomics to the understanding of diseases caused by C. trachomatis was explored in depth by the ICTI Consortium, which was first introduced in the Netherlands in December 2004 at the First Annual Amsterdam Chlamydia Meeting (AACM) and was the subject of a special Drugs of Today supplement published in 2006, entitled "An integrated approach to the understanding of Chlamydia infections". The ICTI Consortium formed the basis for a larger, European Union-funded international effort involving 20 centers, the EpiGenChlamydia Consortium. Major themes, including epidemiology, genetics and immunogenetics, biology and immunology, involving the chlamydiae species infecting humans, such as C. trachomatis, C. psittaci and C. pneumoniae, predominantly presented at the 4th and 5th AACM, are summarized in this second Drugs of Today supplement, as well as timely mini-reviews of the advances made in the field.

The EU FP6 EpiGenChlamydia Consortium: contribution of molecular epidemiology and host-pathogen genomics to understanding Chlamydia trachomatis-related disease.

Chlamydia trachomatis infections are responsible for the world's leading cause of blindness (trachoma) and its most prevalent sexually transmitted disease, which is strongly associated with pelvic inflammatory disease, ectopic pregnancy and tubal infertility. Twin study-based findings of members of EpiGenChlamydia Consortium estimate that there is a 40% genetic predisposition to C. trachomatis infections. It is likely that the advances in human genomics will help to unravel the genetic predisposition at the gene level and will help to define a genetic fingerprint that can be used as a marker for this predisposition. The information gathered to date suggests that this predisposition and the factors contributing to prognosis are multifactorial. The EpiGenChlamydia Consortium aims to structure transnational research to such a degree that comparative genomics and genetic epidemiology can be performed in large numbers of unrelated individuals. Biobanking and data-warehouse building are the most central deliverables of the Coordination Action of the Consortium in Functional Genomics Research. In addition, the collective synergy acquired in this Coordination Action will allow for the generation of scientific knowledge on the C. trachomatis-host interaction, knowledge on the genetic predisposition to C. trachomatis infection and the development of tools for early detection of a predisposition to C. trachomatis infection and its complications. This review summarizes the consortium aims and progress, and future perspectives and directions.

TLR2 haplotypes in the susceptibility to and severity of Chlamydia trachomatis infections in Dutch women.

Chlamydia trachomatis infections may cause several disease conditions ranging from asymptomatic infections to severe upper genital tract pathology, thereby causing significant morbidity worldwide. Remarkable interindividual differences in the clinical course of C. trachomatis infection have been observed, and are mainly based on variation in genes encoding immune-regulatory and bacteria-sensing proteins. Toll-like receptors (TLRs) are closely involved in pathogen recognition and host defense in C. trachomatis infections. The aim of this study is to assess the role of TLR2 single nucleotide polymorphisms and haplotypes in the susceptibility to, and severity of C. trachomatis infections. The study comprised a sexually transmitted disease cohort of 468 Dutch Caucasian women and a control group of 321 women. The subfertility cohort consisted of 56 women with clinically well-defined tubal pathology. The results showed no significant differences in individual TLR2 genotype frequencies in the susceptibility for C. trachomatis infections between the C. trachomatis-positive group and controls. However, haplotype 1 was statistically significant (P = 0.015) and was associated with protection against tubal pathology following C. trachomatis infection. The same haplotype was also significantly decreased (P = 0.021) in increasing severity of C. trachomatis infections (asymptomatic > symptomatic > tubal pathology) suggesting a protective effect of this haplotype against the development of late complications.

TLR9 KO mice, haplotypes and CPG indices in Chlamydia trachomatis infection.

Previous studies have investigated the role of Toll-like receptor (TLR)2 and TLR4 in susceptibility to and severity of Chlamydia trachomatis infections. In this study we employ a unique integrated approach to study the role of the intracellular CpG DNA receptor: we use a murine knockout (KO) model to assess TLR9 relevance, study human TLR9 genotypes and haplotypes in sexually transmitted disease (STD) patients and subfertile women with or without tubal pathology and use in silico TLR9 CpG index calculations to assess potential immunostimulatory properties of the Chlamydia bacterium. Although no significant differences in the course of initial infections were observed between KO mice and wild-type mice the TLR9 KO mice showed a significant level of protection upon reinfection (P = 0.02). We did not observe significant differences in genotype frequencies between C. trachomatis-positive and C. trachomatisnegative women (STD patients). However, haplotype analyses revealed a trend between C. trachomatis-positive and C. trachomatis-negative women in the carriage of haplotype IV (P = 0.061; OR: 2.6; 95% CI: 1.0-6.8). In women with subfertility, odds ratios between 2 and 3 were found for tubal pathology risk, but they did not reach significance due to cohort size limitations. Finally, CpG sequence analysis showed mildly immunostimulatory properties for the genomic sequences of Chlamydia serovars B and D. Based on the murine model, human immunogenetic studies and in silico CpG index analyses, TLR9 seems to play a modest role in C. trachomatis infections. Extension of the human cohorts is necessary to significantly prove the effect in humans.

TLR4 in Chlamydia trachomatis infections: knockout mice, STD patients and women with tubal factor subfertility.

Chlamydia trachomatis is the most prevalent sexually transmitted bacterium in the world with almost 100 million new cases each year, some of which will develop tubal pathology. Clear differences in its clinical course of infections have been observed, and recently it has been shown that 40% is based on host genetic factors. We used an integrated approach based on infection of Toll-like receptor 4 (TLR4) knockout mice and immunogenetic analysis of female sexually transmitted disease (STD) patients (susceptibility) and women with C. trachomatis-associated tubal factor subfertility (severity). The results in TLR4 knockout mice suggest that the protection against reinfection is more solid in normal as compared to the TLR4-deficient mice. In humans the functional TLR4 single nucleotide polymorphism studied was not involved in the susceptibility to infection. However, C. trachomatis immunoglobulin (Ig) G-positive subfertile women with tubal pathology were more than twice as likely to be carriers of the mutant TLR4 +896 G allele as compared to those without tubal pathology; however this observation did not reach statistical significance. In conclusion, both the murine model and the human immunogenetics studies show a slight effect upon TLR4 deficiency in the severity of infection but not in the susceptibility to infection.

A new avenue to investigate: the autophagic process. From Crohn's disease to Chlamydia.

The finding that a variant (T300A) of the autophagyrelated 16-like 1 (ATG16L1) gene is associated with Crohn's disease suggests that the inability to eliminate intestinal intracellular microbes via (macro)autophagy may be involved in the pathogenesis of this disease. The variant induces an autophagy-associated defect in Paneth cells, specialized cells in the crypts of Lieberkuhn within the small intestine that secrete defensins and other antimicrobial peptides. Moreover, other loci, IRGM and LRRK2 involved in autophagy and implicated in clearance of intracellular bacteria have been found to be associated with Crohn's disease. These unexpected findings have changed the focus of research in Crohn's disease and have stimulated an in-depth study of the complex process of autophagy. Autophagy is regulated by many genes and is emerging as a central player in the immunologic control of intracellular bacteria. Chlamydia trachomatis is able to inhibit apoptosis and the production of nuclear factor kappa B (NFkappaB) in order to survive in the host. Extensive studies on association of genes regulating the inflammatory response in experimental models and in humans as revised in other sections of this supplement have failed to explain the longterm complications of C. trachomatis infection. The advances in the molecular pathways of Chlamydia infection and their effects on the Golgi apparatus and other cytoplasmic organelles suggests that defects in autophagic genes may predispose the host to chronic infection and be responsible for the long-term complications. A new genomic approach of the complete autophagic pathway may reveal new insight to understand the presence of a complication in affected individuals, even if at present there is no evidence that C. trachomatis is affected by this pathway.

Cytokine gene polymorphisms and the risk of adenocarcinoma of the stomach in the European prospective investigation into cancer and nutrition (EPIC-EURGAST).

BACKGROUND: The relative contribution to gastric cancer (GC) risk of variants in genes that determine the inflammatory response remains mostly unknown and results from genotyping studies are inconsistent. PATIENTS AND METHODS: A nested case-control study within the prospective European Prospective Investigation into Cancer and Nutrition cohort was carried out, including 248 gastric adenocarcinomas and 770 matched controls. Twenty common polymorphisms at cytokine genes [interleukin (IL)1A, IL1B, IL1RN, IL4, IL4R, IL6, IL8, IL10, IL12A, IL12B, lymphotoxin alpha and tumor necrosis factor (TNF)] were analyzed. Antibodies against Helicobacter pylori (Hp) and CagA were measured. RESULTS: IL1RN 2R/2R genotype [odds ratio (OR) 2.43; 95% confidence interval (CI) 1.19-4.96] and allele IL1RN Ex5-35C were associated with an increased risk of Hp(+) non-cardia GC. IL8 -251AA genotype was associated with a decreased risk of Hp(+) non-cardia GC (OR 0.51; 95% CI 0.32-0.81), mainly of the intestinal type. These associations were not modified by CagA status. Carriers of IL1B -580C and TNF -487A alleles did not associate with an increased risk. A moderately increased risk of Hp(+) non-cardia GC for IL4R -29429T variant was observed (OR 1.74; 95% CI 1.15-2.63). CONCLUSION: This prospective study confirms the association of IL1RN polymorphisms with the risk of non-cardia GC and indicates that IL8 -251T>A may modify the risk for GC.

Levels of ochratoxin A in serum from urban and rural Portuguese populations and estimation of exposure degree.

Urban and rural population exposure to ochratoxin A (OTA) in central zone of Portugal was investigated in three places: Coimbra, Verride and Ereira. The analytical method proposed for the determination of ochratoxin A involved extraction with chloroform-orthophosphoric acid, cleanup through an immunoaffinity column (IAC), high performance liquid chromatography (HPLC) with spectrofluorimetric detection (FD) for separation and identification of ochratoxin A, and confirmation with HPLC-FD after OTA methylation in serum. The limit of quantification of the proposed method was 0.1 microg/L for serum and 0.05 microg/L for blood. OTA recoveries in serum ranged from 70.3% to 115.3% for levels at 0.25 microg/L and 0.5 microg/L, respectively, with a within-day RSD between 8.0% and 16.2%. Ochratoxin A serum levels were evaluated in an hundred and four donors from Coimbra city, Verride, and Ereira. The study revealed a frequency of detection of 100%. The ratio of ochratoxin A level in serum to whole blood was 2.0+/-0.7. The overall concentrations range from 0.25 to 2.49 microg/L, 0.14 to 1.91 microg/L, and 0.19 to 0.96 microg/L, for samples of Verride, Ereira, and Coimbra, respectively. The mean concentration and standard deviation were 0.78+/-0.53 microg/L, 0.44+/-0.31 microg/L, and 0.42+/-0.18 microg/L for the same samples. A significant difference was found in Verride population (P-value=0.000). Levels of OTA are clearly higher in males from rural areas than in females. For all samples, a significant difference was found in Verride male population (P-value=0.014).

Prevalence of macrocreatinkinase type 1 in patients with inflammatory bowel disease.

Macro-creatine-kinases are isoenzymes of creatinine-kinases (CK). They have been classified in two types: type 1 (CK bound to an immunoglobulin) and type 2 (an oligomeric mitochondrial CK). CK type 1 has been found in patients with ulcerative colitis (UC) but not in Crohn's disease (CD). However, there are no studies evaluating macro-creatinkinase prevalence in inflammatory bowel disease (IBD). We included 159 consecutive patients (72 UC, 85 CD; 2 indeterminate colitis). Creatin-kinase total activity and isoenzymes activities were determined. Twelve (16.7%) patients with UC and one of the two patients with indeterminate colitis had serum macro-creatinkinase type 1 while no CD patients displayed this macromolecule (P < 0,001). Sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ratio were calculated for ulcerative colitis versus Crohn's disease diagnosis, being 16.7, 98.9, 92.3, 59, 14.5, and 0.84% respectively. There was no correlation with age, gender, time from diagnosis, associated diseases, concomitant medication or disease activity. In conclusion our data suggests that the presence of macro-CK in IBD favors the diagnosis of ulcerative colitis. Further studies are necessary to understand the significance of this finding in a subset of patients with IBD.

Clinical applications of NOD2/CARD15 mutations in Crohns disease / Aplicaciones clínicas de las mutaciones NOD2/CARD15 en la enfermedad de Crohn

The recent identification of the CARD15/NOD2 gene as a susceptibility locus for Crohns disease represents an important step in the immunopathogenesis of inflammatory bowel disease. The gene explains about 20% of the genetic susceptibility CARD15 mutations are present in 30-50% of CD patients compared to 7-20% of healthy controls. The three risk alleles R702W, G908R and 1007fsInsC in NOD2 associated with susceptibility to Crohns disease have demonstrated a remarkable amount of heterogeneity across ethnicities and populations, with regional variation across Europe. In non-Caucasian populations Crohns disease continues to increase in incidence but this increase appears not to be a consequence of variation in NOD2. Genotype-phenotype analyses demonstrated an association of these mutations with ileum-specific disease and an increased incidence of the fibrostenotic phenotype. Although CARD15 variants do not predict response to the TNF alpha monoclonal antibodies, there are no data available on the possible influence of CARD15 mutations on response to other drugs. Screening for CARD15 mutations in order to identify high-risk individuals or to introduce an individualized disease management is therefore currently not recommended.(AU)

La reciente identificación del gen CARD15/NOD2 como locus de susceptibilidad para la enfermedad deCrohn representa un paso importante en la inmumopatogénesis de la enfermedad inflamatoria intestinal. El gen explica alrededor del 20% de la susceptibilidadgenética. Las mutaciones en CARD15 aparecen en 30-50% de los pacientes con enfermedad de Crohn en comparación con 7-20% en los controles sanos. Los tres alelos de riesgo R702W, G908R y 100fsInsC delNOD2 asociados con susceptibilidad a la enfermedad de Crohn han demostrado una significativa heterogeneidadentre diferentes grupos étnicos y poblaciones, con variaciones regionales en toda Europa. En las poblacionesno caucásicas la enfermedad de Crohn aumenta en incidencia pero esta incidencia no parece ser una consecuencia de variación del NOD2. Los análisis de genotipo/fenotipo demostraron una asociación deestas mutaciones con enfermedad de localización ileal y una mayor incidencia del fenotipo fibroestenosante. Si bien las variantes del CARD15 no predicen una respuesta a los anticuerpos monoclonales TNF alfa, no hay datos disponibles sobre la posible influencia de las mutaciones del CARD15 como respuesta a otras drogas. Por consiguiente no podemos recomendar exámenes para las mutaciones del CARD15 con el fin de identificar individuos de alto riesgo ni para introducir un manejo individualizado de la enfermedad.(AU)