954 resultados para Loci
Resumo:
Peroxisome proliferator activated receptor-gamma 2 (PPARG2) is a nuclear hormone receptor of ligand-dependent ranscription factor involved in adipogenesis and a molecular target of the insulin sensitizers thiazolidinediones. We addressed the question of whether the 3 variants (-1279G/A, Pro12Ala, and His478His) in the PPARG2 gene are associated with type 2 diabetes mellitus and its related traits in a South Indian population. The study subjects (1000 type 2 diabetes mellitus and 1000 normal glucose-tolerant subjects) were chosen randomly from the Chennai Urban Rural Epidemiology Study, an ongoing population-based study in southern India. The variants were screened by single-stranded conformational variant, direct sequencing, and restriction fragment length polymorphism. Linkage disequilibrium was estimated from the estimates of haplotypic frequencies. The -1279G/A, Pro12Ala, and His478His variants of the PPARG2 gene were not associated with type 2 diabetes mellitus. However, the 2-loci analyses showed that, in the presence of Pro/Pro genotype of the Pro12Ala variant, the -1279G/A promoter variant showed increased susceptibility to type 2 diabetes mellitus (odds ratio, 2.092; 95% confidence interval, 1.22-3.59; P = .008), whereas in the presence of 12Ala allele, the -1279G/A showed a protective effect against type 2 diabetes mellitus (odds ratio, 0.270; 95% confidence interval, 0.15-0.49; P < .0001). The 3-loci haplotype analysis showed that the A-Ala-T (-1279G/A-Pro12Ala-His478His) haplotype was associated with a reduced risk of type 2 diabetes mellitus (P < .0001). Although our data indicate that the PPARG2 gene variants, independently, have no association with type 2 diabetes mellitus, the 2-loci genotype analysis involving -1279G/A and Pro12Ala variants and the 3-loci haplotype analysis have shown a significant association with type 2 diabetes mellitus in this South Indian population. (C) 2010 Elsevier Inc. All rights reserved.
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This study analyzes civic activity, citizenship and their gendered manifestations in contemporary Russia. It is based on a case study conducted in the city of Tver , located in the vicinity of Moscow, during 2001-2005. The data consists of interviews with civic activists and municipal and regional authorities; observations of civic organizations; and a quantitative survey conducted among local civic groups. The theoretical and methodological framework of the study draws upon a micro perspective on organization, discourse analysis, gender and citizenship theories and Pierre Bourdieu s theory of fields and capital. This study develops theoretical understanding of the characteristics and logic of civic organization in Russia. It shows that social class centrally structures the field of civic activity. Organizations can be seen as a vehicle of the educated class to advocate their interests, help themselves and seek both social and individual-level change. The study also argues that civic organizations founded during the post-Soviet era are often an institutionalized form of informal social networks. Networks, which were a central element of everyday interaction in Soviet society, are a resource and often the only resource available that can be made use of in contemporary organizational activities. The study argues that gender operates as a key structuring principle in the Russian socio-political community. Civic activity is often discursively associated with femininity and institutional politics with masculinity. Women tend to participate more than men in civic organizations, while men dominate the formal political domain. The study shows that civic organizations are important loci of communality. This communality, however, differs from the communality envisioned in the communitarian and social capital debates in the West. It is selective communality , as it is restricted to the members of the organizations and does not create generalized reciprocity and trust. Civic organizations tend to build upon and reproduce the traditional Russian organizational form of circles , kruzhki. Along with the analysis of civic activities, the study also examines the redefinition of the role and functions of the state. The authorities interviewed in this study understand civic organizations as serving those goals and interests determined by the authorities, instead of viewing them as sites of citizens self-organization around interests and problems citizens themselves deem important, or as a counterforce to the state. By contrast, civic activists understand the core of organizational activity to be advocacy of their interests and rights, tackling social problems, the pursuit of wider social change and self-help. Co-operation between authorities and organizations tends to be personified and based upon unequal, hierarchical patron-client arrangements, which inhibits the development of democratic governance. The study will be published in Routledge Contemporary Russia and Eastern Europe Series later this year.
Resumo:
PURPOSE: To report the linkage analysis of retinitis pigmentosa (RP) in an Indian family. METHODS: Individuals were examined for symptoms of retinitis pigmentosa and their blood samples were withdrawn for genetic analysis. The disorder was tested for linkage to known 14 adRP and 22 arRP loci using microsatellite markers. RESULTS: Seventeen individuals including seven affecteds participated in the study. All affected individuals had typical RP. The age of onset of the disease ranged from 8-18 years. The disorder in this family segregated either as an autosomal recessive trait with pseudodominance or an autosomal dominant trait. Linkage to an autosomal recessive locus RP28 on chromosome 2p14-p15 was positive with a maximum two-point lod score of 3.96 at theta=0 for D2S380. All affected individuals were homozygous for alleles at D2S2320, D2S2397, D2S380, and D2S136. Recombination events placed the minimum critical region (MCR) for the RP28 gene in a 1.06 cM region between D2S2225 and D2S296. CONCLUSIONS : The present data confirmed linkage of arRP to the RP28 locus in a second Indian family. The RP28 locus was previously mapped to a 16 cM region between D2S1337 and D2S286 in a single Indian family. Haplotype analysis in this family has further narrowed the MCR for the RP28 locus to a 1.06 cM region between D2S2225 and D2S296. Of 15 genes reported in the MCR, 14 genes (KIAA0903, OTX1, MDH1, UGP2, VPS54, PELI1, HSPC159, FLJ20080, TRIP-Br2, SLC1A4, KIAA0582, RAB1A, ACTR2, and SPRED2) are either expressed in the eye or retina. Further study needs to be done to test which of these genes is mutated in patients with RP linked to the RP28 locus.
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Autism is a childhood-onset developmental disorder characterized by deficits in reciprocal social interaction, verbal and non-verbal communication, and dependence on routines and rituals. It belongs to a spectrum of disorders (autism spectrum disorders, ASDs) which share core symptoms but show considerable variation in severity. The whole spectrum affects 0.6-0.7% of children worldwide, inducing a substantial public health burden and causing suffering to the affected families. Despite having a very high heritability, ASDs have shown exceptional genetic heterogeneity, which has complicated the identification of risk variants and left the etiology largely unknown. However, recent studies suggest that rare, family-specific factors contribute significantly to the genetic basis of ASDs. In this study, we investigated the role of DISC1 (Disrupted-in-schizophrenia-1) in ASDs, and identified association with markers and haplotypes previously associated with psychiatric phenotypes. We identified four polymorphic micro-RNA target sites in the 3 UTR of DISC1, and showed that hsa-miR-559 regulates DISC1 expression in vitro in an allele-specific manner. We also analyzed an extended autism pedigree with genealogical roots in Central Finland reaching back to the 17th century. To take advantage of the beneficial characteristics of population isolates to gene mapping and reduced genetic heterogeneity observed in distantly related individuals, we performed a microsatellite-based genome-wide screen for linkage and linkage disequilibrium in this pedigree. We identified a putative autism susceptibility locus on chromosome 19p13.3 and obtained further support for previously reported loci at 1q23 and 15q11-q13. To follow-up these findings, we extended our study sample from the same sub-isolate and initiated a genome-wide analysis of homozygosity and allelic sharing using high-density SNP markers. We identified a small number of haplotypes shared by different subsets of the genealogically connected cases, along with convergent biological pathways from SNP and gene expression data, which highlighted axon guidance molecules in the pathogenesis of ASDs. In conclusion, the results obtained in this thesis show that multiple distinct genetic variants are responsible for the ASD phenotype even within single pedigrees from an isolated population. We suggest that targeted resequencing of the shared haplotypes, linkage regions, and other susceptibility loci is essential to identify the causal variants. We also report a possible micro-RNA mediated regulatory mechanism, which might partially explain the wide-range neurobiological effects of the DISC1 gene.
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Autoimmune diseases are more common in dogs than in humans and are already threatening the future of some highly predisposed dog breeds. Susceptibility to autoimmune diseases is controlled by environmental and genetic factors, especially the major histocompatibility complex (MHC) gene region. Dogs show a similar physiology, disease presentation and clinical response as humans, making them an excellent disease model for autoimmune diseases common to both species. The genetic background of canine autoimmune disorders is largely unknown, but recent annotation of the dog genome and subsequent development of new genomic tools offer a unique opportunity to map novel autoimmune genes in various breeds. Many autoimmune disorders show breed-specific enrichment, supporting a strong genetic background. Furthermore, the presence of hundreds of breeds as genetic isolates facilitates gene mapping in complex autoimmune disorders. Identification of novel predisposing genes establishes breeds as models and may reveal novel candidate genes for the corresponding human disorders. Genetic studies will eventually shed light on common biological functions and interactions between genes and the environment. This study aimed to identify genetic risk factors in various autoimmune disorders, including systemic lupus erythematosus (SLE)-related diseases, comprising immune-mediated rheumatic disease (IMRD) and steroid-responsive meningitis arteritis (SMRA) as well as Addison s disease (AD) in Nova Scotia Duck Tolling Retrievers (NSDTRs) and chronic superficial keratitis (CSK) in German Shepherd dogs (GSDs). We used two different approaches to identify genetic risk factors. Firstly, a candidate gene approach was applied to test the potential association of MHC class II, also known as a dog leukocyte antigen (DLA) in canine species. Secondly, a genome-wide association study (GWAS) was performed to identify novel risk loci for SLE-related disease and AD in NSDTRs. We identified DLA risk haplotypes for an IMRD subphenotype of SLE-related disease, AD and CSK, but not in SMRA, and show that the MHC class II gene region is a major genetic risk factor in canine autoimmune diseases. An elevated risk was found for IMRD in dogs that carried the DLA-DRB1*00601/DQA1*005011/DQB1*02001 haplotype (OR = 2.0, 99% CI = 1.03-3.95, p = 0.01) and for ANA-positive IMRD dogs (OR = 2.3, 99% CI = 1.07-5.04, p-value 0.007). We also found that DLA-DRB1*01502/DQA*00601/DQB1*02301 haplotype was significantly associated with AD in NSDTRs (OR = 2.1, CI = 1.0-4.4, P = 0.044) and the DLA-DRB1*01501/DQA1*00601/DQB1*00301 haplotype with the CSK in GSDs (OR=2.67, CI=1.17-6.44, p= 0.02). In addition, we found that homozygosity for the risk haplotype increases the risk for each disease phenotype and that an overall homozygosity for the DLA region predisposes to CSK and AD. Our results have enabled the development of genetic tests to improve breeding practices by avoiding the production of puppies homozygous for risk haplotypes. We also performed the first successful GWAS for a complex disease in dogs. With less than 100 cases and 100 controls, we identified five risk loci for SLE-related disease and AD and found strong candidate genes involved in a novel T-cell activation pathway. We show that an inbred dog population has fewer risk factors, but each of them has a stronger genetic risk. Ongoing studies aim to identify the causative mutations and bring new knowledge to help diagnostics, treatment and understanding of the aetiology of SLE-related diseases.
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It is currently believed that an unsubstituted axial hydroxyl at the specificity-determining C-4 locus of galactose is indispensable for recognition by galactose/N-acetylgalactosamine-specific lectins. Titration calorimetry demonstrates that 4-methoxygalactose retains binding allegiance to the Moraceae lectin jacalin and the Leguminosae lectin, winged bean (basic) agglutinin (WBA I). The binding reactions were driven by dominant favorable enthalpic contributions and exhibited significant enthalpy-entropy compensation. Proton NMR titration of C-methoxygalactose with jacalin and WBA I resulted in broadening of the sugar resonances without any change in chemical shift. The alpha-and beta-anomers of 4-methoxygalactose were found to be in slow exchange with free and lectin-bound states. Both the anomers experience magnetically equivalent environments at the respective binding sites. The binding constants derived from the dependence of NMR line widths on 4-methoxygalactose concentration agreed well with those obtained from titration calorimetry. The results unequivocally demonstrate that the loci corresponding to the axially oriented C-4 hydroxyl group of galactose within the primary binding site of these lectins exhibit plasticity. These analyses suggest, for the first time, the existence of C-H ... O-type hydrogen-bond(s) in protein-carbohydrate interactions in general and between the C-4 locus of galactose derivative and the lectins jacalin and WBA I in particular.
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Consanguineous marriages are strongly favoured in the state of Karnataka. Of 65492 marriages studied 33·07% were consanguineous, equivalent to a coefficient of inbreeding (F) of 0·0298. The twinning rate was low, 6·9 per thousand, whereas the secondary sex ratio, 0·5221, was higher than in comparable major human populations. Consanguinity exerted no significant effect on either parameter. The results also indicate that consanguinity is not associated with excess antenatal losses and suggest the possibility of enhanced selection against mutations at X chromosome loci.
Resumo:
Tämän tutkimuksen tavoitteena oli selvittää koirarotujen sisäistä ja välistä perinnöllistä muuntelua ja populaatioiden rakenteita. Tutkimuksessa käytettiin Finnzymes Oy:ltä saatua koirien mikrosatelliittimerkkeihin perustuvaa genotyypitysaineistoa. Lopullisessa aineistossa oli 395 koiraa kymmenestä keskenään varsin erilaisesta rodusta. Koirien määrä rotua kohti vaihteli 31:stä 53:een. Tutkimuksessa käytettiin 18 mikrosatelliittilokusta. Alleelirikkaus vaihteli mikrosatelliittilokuksissa välillä 2,0 – 9,9. Kaikkein muuntelevin lokus oli AHT137 ja vähiten muunteleva AHTk211. Jackrussellinterrierin alleelirikkaus oli yli kaikkien lokusten tarkasteltuna suurinta ja cavalier kingcharlesinspanielin pienintä. Eniten Hardy-Weinbergin tasapainosta poikkeavia mikrosatelliittilokuksia oli schipperke- rodulla. Coton de tulearin, saksanpaimenkoiran ja suomenlapinkoiran kaikki mikrosatelliittilokukset olivat Hardy-Weinbergin tasapainossa. Cavalier kingcharlesinspanielin havaittu heterotsygotia-aste oli matalin kaikkien lokusten yli tarkasteltuna (0,50) ja suomenlapinkoiran korkein (0,73). Ainoat tilastollisesti merkitsevät FIS-arvot olivat schipperken lokuksessa INU030 (0,39) ja kaikkien lokusten yli tarkasteltuna (0,11). Eniten populaatioiden välisiin eroihin perustuvaa muuntelua oli cavalier kingcharlesinspanielin ja pitkäkarvaisen collien välillä (FST = 0,34) ja vähiten chihuahuan ja coton de tulearin välillä (FST = 0,07). Koko aineistossa noin 17,7 % populaatioiden välisestä geneettisestä muuntelusta johtui populaatioiden välisistä eroista. Rodut ovat tulosten perusteella selvästi erillisiä populaatioita. Coton de tulearin alleeliparit olivat selvästi eniten kytkentäepätasapainossa keskenään (94) ja tiibetinspanielin vähiten (15). Pitkäkarvaisen collien tehollinen populaatiokoko oli pienin (35) ja chihuahuan suurin (86). U seiden populaatiogeneettisten tunnuslukujen perusteella nousivat esiin cavalier kingcharlesinspanieli, pitkäkarvainen collie ja schipperke perinnöllisen muuntelun vähäisyyden perusteella ja chihuahua, jackrussellinterrieri ja suomenlapinkoira keskimääräistä suuremman perinnöllisen muuntelun perusteella. Selityksiä geneettisen monimuotoisuuden vaihteluun näillä roduilla löytyy rotujen historiasta.
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Distamycin and netropsin, a class of minor groove binding nonintercalating agents, are characterized by their B-DNA and A-T basespecific interactions. To understand the CQI I ~OIT~ ~ I ~ ~aOnMd ~c hemical basis of the above specificities, the DNA-binding characteristics of a novel synthetic analogue of distamycin have been studied. The analogue, mPD derivative, has the requisite charged end groups and a number of potential hydrogen-bonding loci equal to those of distamycin. The difference in the backbone curvatures of the ligands, distamycin, the mPD derivative, and NSC 101327 (another structurally analogous compound),is a major difference between these ligands. UV and CD spectrosoopic studies reported here show the following salient features: The mPD derivative recognizes only B-DNA, to which it binds via the minor groove. On the other hand, unlike distamycin, it binds with comparable affinities to A-T and G-C base pairs in a natural DNA. These DNA-binding properties are compared with those reported earlier for distamycin and NSC 101327 [Zimmer, Ch., & Wahnert, U. (1986) Prog. Biophys. Mol. Biol. 47, 31-1121. The backbone structures of these three ligands were compared to show the progressive decrease in curvatures in the order distamycin, mPD derivative, and NSC 101327. The plausible significance of the backbone curvature vis-&vis the characteristic B-DNA and AT-specific binding of distamycin is discussed. To our knowledge, this is the first attempt (with a model synthetic analogue) to probe the possible influence of backbone curvature upon the specificity of interactions of the distamycin class of groove-binding ligands with DNA.
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Both inherited genetic variations and somatically acquired mutations drive cancer development. The aim of this thesis was to gain insight into the molecular mechanisms underlying colorectal cancer (CRC) predisposition and tumor progression. Whereas one-third of CRC may develop in the context of hereditary predisposition, the known highly penetrant syndromes only explain a small fraction of all cases. Genome-wide association studies have shown that ten common single nucleotide polymorphisms (SNPs) modestly predispose to CRC. Our population-based sample series of around thousand CRC cases and healthy controls was genotyped for these SNPs. Tumors of heterozygous patients were analyzed for allelic imbalance, in an attempt to reveal the role of these SNPs in somatic tumor progression. The risk allele of rs6983267 at 8q24 was favored in the tumors significantly more often than the neutral allele, indicating that this germline variant is somatically selected for. No imbalance targeting the risk allele was observed in the remaining loci, suggesting that most of the low-penetrance CRC SNPs mainly play a role in the early stages of the neoplastic process. The ten SNPs were further analyzed in 788 CRC cases, 97 of which had a family history of CRC, to evaluate their combined contribution. A significant association appeared between the overall number of risk alleles and familial CRC and these ten SNPs seem to explain around 9% of the familial clustering of CRC. Finding more CRC susceptibility alleles may facilitate individualized risk prediction and cancer prevention in the future. Microsatellite instability (MSI), resulting from defective mismatch repair function, is a hallmark of Lynch syndrome and observed in a subset of all CRCs. Our aim was to identify microsatellite frameshift mutations that inactivate tumor suppressor genes in MSI CRCs. By sequencing microsatellite repeats of underexpressed genes we found six novel MSI target genes that were frequently mutated in 100 MSI CRCs: 51% in GLYR1, 47% in ABCC5, 43% in WDTC1, 33% in ROCK1, 30% in OR51E2, and 28% in TCEB3. Immunohistochemical staining of GLYR1 revealed defective protein expression in homozygously mutated tumors, providing further support for the loss of function hypothesis. Another mutation screening effort sought to identify MSI target genes with putative oncogenic functions. Microsatellites were similarly sequenced in genes that were overexpressed and, upon mutation, predicted to avoid nonsense-mediated mRNA decay. The mitotic checkpoint kinase TTK harbored protein-elongating mutations in 59% of MSI CRCs and the mutant protein was detected in heterozygous MSI CRC cells. No checkpoint dysregulation or defective protein localization was observable however, and the biological relevance of this mutation may hence be related to other mechanisms. In conclusion, these two large-scale and unbiased efforts identified frequently mutated genes that are likely to contribute to the development of this cancer type and may be utilized in developing diagnostic and therapeutic applications.
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Fluorescence and stopped-flow spectrophotometric studies on three plant lectins fromPsophocarpus tetragonolobus (winged bean),Glycine max (soybean) andArtocarpus integrifolia (jack fruit) have been studied usingN-dansylgalactosamine as a fluorescent ligand. The best monosaccharide for the winged bean agglutinin I (WBA I) and soybean (SBA) is Me-agrGalNAc and for jack fruit agglutinin (JFA) is Me-agrGal. Examination of the percentage enhancement and association constants (1.51×106, 6.56×106 and 4.17×105 M–1 for SBA, WBA I and JFA, respectively) suggests that the combining regions of the lectins SBA and WBA I are apolar whereas that of JFA is polar. Thermodynamic parameters obtained for the binding of several monosaccharides to these lectins are enthalpically favourable. The binding of monosaccharides to these lectins suggests that the-OH groups at C-1, C-2, C-4 and C-6 in thed-galactose configuration are important loci for interaction with these lectins. An important finding is that the JFA binds specifically to Galß1-3GaINAc with much higher affinity than the other disaccharides which are structurally and topographically similar.The results of stopped-flow spectrometry on the binding ofN-dansylgalactosamine to these lectins are consistent with a bimolecular single step mechanism. The association rate constants (2.4×105, 1.3×104, and 11.7×105 M–1 sec–1 for SBA, WBA I and JFA, respectively) obtained are several orders of magnitude slower than the ones expected for diffusion controlled reactions. The dissociation rate constants (0.2, 3.2×10–2, 83.3 sec–1 for SBA, WBA I and JFA, respectively) obtained for the dissociation ofN-dansylgalactosamine from its lectin complex are slowest for SBA and WBA I when compared with any other lectin-ligand dissociation process.
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A continuum model based on the critical state theory of soil mechanics is used to generate stress and density profiles, and to compute discharge velocities for the plane flow of cohesionless materials. Two types of yield loci are employed, namely, a yield locus with a corner, and a smooth yield locus. The yield locus with a corner leads to computational difficulties. For the smooth yield locus, results are found to be relatively insensitive to the shape of the yield locus, the location of the upper traction-free surface and the density specified on this surface. This insensitivity arises from the existence of asymptotic stress and density fields, to which the solution tends to converge on moving down the hopper. Numerical and approximate analytical solutions are obtained for these fields and the latter is used to derive an expression for the discharge velocity. This relation predicts discharge velocities to within 13% of the exact (numerical) values. While the assumption of incompressibility has been frequently used in the literature, it is shown here that in some cases, this leads to discharge velocities which are significantly higher than those obtained by the incorporation of density variation.
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Multiple sclerosis (MS) is the most common cause of neurological disability in young adults, affecting more than two million people worldwide. It manifests as a chronic inflammation in the central nervous system (CNS) and causes demyelination and neurodegeneration. Depending on the location of the demyelinated plaques and axonal loss, a variety of symptoms can be observed including deficits in vision, coordination, balance and movement. With a typical age of onset at 20-40 years, the social and economic impacts of MS on lives of the patients and their families are considerable. Unfortunately the current treatments are relatively inefficient and the development of more effective treatments has been impeded by our limited understanding of the causes and pathogenesis of MS. Risk of MS is higher in biological relatives of MS patients than in the general population. Twin and adoption studies have shown that familial clustering of MS is explained by shared genetic factors rather than by shared familial environment. While the involvement of the human leukocyte antigen (HLA) genes was first discovered four decades ago, additional genetic risk factors have only recently been identified through genome-wide association studies (GWAS). Current evidence suggests that MS is a highly polygenic disease with perhaps hundreds of common variants with relatively modest effects contributing to susceptibility. Despite extensive research, the majority of these risk factors still remain to be identified. In this thesis the aim was to identify novel genes and pathways involved in MS. Using genome-wide microarray technology, gene expression levels in peripheral blood mononuclear cells (PBMC) from 12 MS patients and 15 controls were profiled and more than 600 genes with altered expression in MS were identified. Three of five selected findings, DEFA1A3, LILRA4 and TNFRSF25, were successfully replicated in an independent sample. Increased expression of DEFA1A3 in MS is a particularly interesting observation, because its elevated levels have previously been reported also in several other autoimmune diseases. A systematic review of seven microarray studies was then performed leading to identification of 229 genes, in which either decreased or increased expression in MS had been reported in at least two studies. In general there was relatively little overlap across the experiments: 11 of the 229 genes had been reported in three studies and only HSPA1A in four studies. Nevertheless, these 229 genes were associated with several immunological pathways including interleukin pathways related to type 2 and type 17 helper T cells and regulatory T cells. However, whether these pathways are involved in causing MS or related to secondary processes activated after disease onset remains to be investigated. The 229 genes were also compared with loci identified in published MS GWASs. Single nucleotide polymorphisms (SNP) in 17 of the 229 loci had been reported to be associated with MS with P-value less than 0.0001 including variants in CXCR4 and SAPS2, which were the only loci where evidence for correlation between the associated variant and gene expression was found. The CXCR4 variant was further tested for association with MS in a large case-control sample and the previously reported suggestive association was replicated (P-value is 0.0004). Finally, common genetic variants in candidate genes, which had been selected on the basis of showing association with other autoimmune diseases (MYO9B) or showing differential expression in MS in our study (DEFA1A3, LILRA4 and TNFRSF25), were tested for association with MS, but no evidence of association was found. In conclusion, through a systematic review of genome-wide expression studies in MS we have identified several promising candidate genes and pathways for future studies. In addition, we have replicated a previously suggested association of a SNP variant upstream of CXCR4 with MS. Keywords: autoimmune disease, common variant, CXCR4, DEFA1A3, HSPA1A,gene expression, genetic association, GWAS, MS, multiple sclerosis, systematic review
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Lamb-wave-based damage detection methods using the triangulation technique are not suitable for handling structures with complex shapes and discontinuities as the parametric/analytical representation of these structures is very difficult. The geodesic concept is used along with the triangulation technique to overcome the above problem. The present work is based on the fundamental fact that a wave takes the minimum energy path to travel between two points on any multiply connected surface and this reduces to the shortest distance path or geodesic. The geodesics are computed on the meshed surface of the structure using the fast marching method. The wave response matrix of the given sensor configuration for the healthy and the damaged structure is obtained experimentally. The healthy and damage response matrices are compared and their difference gives the time information about the reflection of waves from the damage. A wavelet transform is used to extract the arrival time information of the wave scattered by the damage from the acquired Lamb wave signals. The computed geodesics and time information are used in the ellipse algorithm of triangulation formulation to locate the loci of possible damage location points for each actuator-sensor pair. The results obtained for all actuator-sensor pairs are combined and the intersection of multiple loci gives the damage location result. Experiments were conducted in aluminum and composite plate specimens to validate this method.
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Lymphocytes collected from rhinitis subjects with strong positive skin reactions to the pollen allergens of Parthenium hysterophorus (American feverfew) having moderate to high titres of Parthenium-specific serum IgE were analysed for association of HLA-antigens covering 13 specificities of HLA-A, 17 specificities of HLA-B and eight specificities of HLA-DR loci by the NIH two-stage microlymphocytotoxicity assay. Comparison of the phenotypic frequencies of HLA-A and B antigens between Parthenium rhinitis subjects (n= 22) and control subjects (n= 137) did not suggest any significant association when tested for these antigen specificities. A significant correlation in the association of HLA-DR3 antigen with a relative risk of 11·33, however, was observed in Parthenium rhinitis subjects (n= 30) when compared to controls (n= 50).