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Terms modified by Hardy Selected AbstractsAngiotensin-I-converting enzyme insertion/deletion polymorphism and high urinary albumin concentration in French Type 2 diabetes patientsDIABETIC MEDICINE, Issue 8 2003S. Hadjadj Abstract Aims Family-based studies suggest a genetic basis for nephropathy in Type 2 diabetes. The angiotensin-I-converting enzyme (ACE) gene is a candidate gene for Type 1 diabetes nephropathy. We assessed the association between high urinary albumin concentration and ACE insertion/deletion (I/D) polymorphism, in French Type 2 diabetes patients. Methods We studied 3139 micro/macroalbuminuric French patients recruited in the DIABHYCAR Study, an ACE inhibition trial in Type 2 diabetes patients with renal and cardiovascular outcomes. The main inclusion criteria were age , 50 years, urinary albumin concentration , 20 mg/l assessed centrally during two consecutive screening visits, and plasma creatinine concentration , 150 µmol/l. These patients were compared with 605 normoalbuminuric (NA; urinary albumin concentration < 10 mg/l at first screening for the DIABHYCAR Study) French patients. ACE I/D genotype was determined by nested polymerase chain reaction. Results The ACE I/D polymorphism was in Hardy,Weinberg equilibrium. The distribution of genotypes did not differ significantly between micro/macroalbuminuric and NA patients: 552 and 115 II, 1468 and 282 ID, 1119 and 208 DD (P = 0.67). However, the ACE D allele was more frequent among normotensive micro/macroalbuminuric patients than among NA patients (P = 0.039). Conclusions The ACE I/D polymorphism was not associated with high urinary albumin concentration in French Type 2 diabetes patients. [source] "Paterniplex", a highly discriminative decaplex STR multiplex tailored for investigating special problems in paternity testingELECTROPHORESIS, Issue 21 2007Thomas Betz Abstract The goal of the study was to develop a STR multiplex ("Paterniplex") that is , as supplement to commercially available multiplex kits like the Identifiler® kit (Applied Biosystems, Foster City, CA) , suitable for solving complex paternity cases such as deficiency cases or cases with mutations. The Paterniplex comprises the nine highly polymorphic STRs D8S1132, D7S1517, D10S2325, D12S391, Se33, D17S976, Penta E, Penta D and FGA in addition to Amelogenin as sex determination marker. The loci were selected because of their high degree of polymorphism (higher than that of the widely used TH01 marker). Only one locus, FGA, is shared with the Identifiler kit to avoid sample mix up. The study further gives details on the population genetics of the loci in a German Caucasian population (allelic distribution, Hardy,Weinberg Equilibrium and forensic efficiency markers such as the Discriminating Power) and three examples for cases that could not be solved using commercially available kits alone, but using the Paterniplex in addition to a commercial kit. [source] Polymorphisms in the thymidylate synthase promoter and the DNA repair genes XRCC1 and XPD in a Brazilian populationENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 9 2006Renata Canalle Abstract Polymorphisms in genes responsible for maintaining genomic integrity are potential modifiers of disease risk. Since considerable interindividual and interethnic variation in DNA repair capacity has been associated with polymorphic alleles, we evaluated the frequency of the 2R/3R variants in the TS promoter, Arg194Trp and Arg399Gln in the XRCC1 gene, and Asp312Asn and Lys751Gln in the XPD gene in 364 healthy individuals from a Brazilian population separated by ethnicity (European ancestry and African ancestry). The genotypes were determined by PCR (TS) or by PCR-RFLP (XRCC1 and XPD). The frequency of the TS 3R allele was 0.56 for whites and 0.51 for nonwhites. In the case of the XRCC1 MspI polymorphism, the allele frequencies were 0.09 for 194Trp in both nonwhites and whites and 0.27 and 0.28 for 399Gln in nonwhites and whites, respectively. For the XPD 312Asn allele, we found a frequency of 0.25 in white individuals, which was significantly different (P = 0.025) from that seen in nonwhites (0.15). Similarly, the 751Gln polymorphic allele of the XPD gene was significantly more frequent (P < 0.002) in whites (0.30) than in nonwhites (0.20). The genotype frequencies were within Hardy,Weinberg equilibrium. We concluded that the genotype and allele frequencies of XPD gene polymorphism differed between white and nonwhite Brazilians, and that the frequencies of the XPD 312Asn and XRCC1 399Gln alleles in this Brazilian population showed ethnic variability when compared with those observed in other populations. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] STrengthening the REporting of Genetic Association studies (STREGA) , an extension of the STROBE statementEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2009Julian Little Abstract Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA) initiative builds on the STrengthening the Reporting of OBservational Studies in Epidemiology (STROBE) Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modelling haplotype variation, Hardy,Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed, but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct or analysis. [source] GENETIC STUDY: 5-HTTLPR polymorphism, mood disorders and MDMA use in a 3-year follow-up studyADDICTION BIOLOGY, Issue 1 2010Rocío Martín-Santos ABSTRACT A 3-year longitudinal prospective study was conducted to compare the incidence of substance use disorders (SUD) and non-substance use disorders (NSUD) among ecstasy users and two control groups: one of cannabis users and the other of non-drug users. The 5-HTTLPR polymorphism related to NSUD was also studied. A total of 94 subjects were included: 37 ecstasy users, 23 cannabis users and 34 non-drug users. SUD and NSUD disorders were diagnosed according to the fourth edition of the Diagnostic and Statistical Manual of Mental Health Disorders criteria using the Psychiatric Research Interview for Substance and Mental Disorders. Incidence Rates (IR) are presented. The 5-HTTLPR polymorphism was analyzed. Hardy,Weinberg equilibrium was studied. The results of the study showed that the highest IR of SUD was cannabis abuse/dependence in both the ecstasy (IR: 48.6/100 person,year) and cannabis (IR: 2.5/100 person,year) groups. There were no new cases of SUD in non-drug users at follow-up. The highest IR of NSUD was primary mood disorder in both the ecstasy (IR: 4.2/100 person,year) and in the non-drug (IR: 1.3/100 person,year) groups (P < 0.282). There were no new cases of NSUD in the cannabis group at follow-up. 5-HTTLPR polymorphism was associated with lifetime of primary mood disorders in ecstasy group (P = 0.018). Ecstasy use was associated with a higher rate of cannabis abuse/dependence disorders and mood disorders than cannabis use. In the ecstasy users, 5-HTTLPR polymorphism may result in a high vulnerability to primary mood disorders. [source] HLA allele and haplotype frequencies in the Albanian population and their relationship with the other European populationsINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 6 2009G. Sulcebe Summary Human leucocyte antigen (HLA) alleles are very interesting markers in identifying population relationships. Moreover, their frequency distribution data are important in the implementation of donor,recipient registry programs for transplantation purposes and also in determining the genetic predisposition for many diseases. For these reasons, we studied the HLA class I and II allele and haplotype frequencies in 160 healthy, unrelated Albanian individuals originating from all regions of the country. The HLA genotyping was performed through a 2-digit resolution SSOP method. The data were analysed with Arlequin and Phylip programs. No deviation was found from the Hardy,Weinberg equilibrium. A total of 17 A*, 30 B*, 12 Cw*, 13 DRB1* and 5 DQB1* alleles were identified. The six most frequent HLA-A-B-DRB1 haplotypes were A*02,B*18,DRB1*11 (5.60%), A*02,B*51,DRB1*16 (4.74%), A*01,B*08,DRB1*03 (3.48%), A*24,B*35,DRB1*11 (2.77%), A*02,B*51,DRB1*13 (2.21%), A*24,B*35,DRB1*14 (1.89%). Interestingly, 12 HLA-A-B-Cw-DRB1-DQB1 haplotypes occurred at a frequency >1%. When compared with the other populations, a close relationship was found with North Greek, Bulgarian, Macedonian, Romanian, Turkish, Cretan, Serbian, Croatian and Italian populations. A higher differentiation in allele frequency level was found with Western Europe populations. These data are the first report of HLA allele and haplotype distribution in an Albanian population inside this country. When compared with other populations, their distribution frequencies show close similarities with neighbouring populations of the entire Balkan area. [source] Evaluation of IL10, IL19 and IL20 gene polymorphisms and chronic hepatitis B infection outcomeINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 3 2008Ann L. Truelove Summary Hepatitis B virus (HBV) infection remains a serious global health problem despite the availability of a highly effective vaccine. Approximately 5% of HBV-infected adults develop chronic hepatitis B, which may result in liver cirrhosis or hepatocellular carcinoma. Variants of interleukin-10 (IL10) have been previously associated with chronic hepatitis B infection and progression to hepatocellular carcinoma. Single nucleotide polymorphisms (SNP; n = 42) from the IL10, IL19 and IL20 gene regions were examined for an association with HBV infection outcome, either chronic or recovered, in a nested case,control study of African Americans and European Americans. Among African Americans, three nominally statistically significant SNP associations in IL10, two in IL20, and one haplotype association were observed with different HBV infection outcomes (P = 0.005,0.04). A SNP (rs1518108) in IL20 deviated significantly from Hardy,Weinberg equilibrium in African Americans, with a large excess of heterozygotes in chronic HBV-infected cases (P = 0.0006), which suggests a strong genetic effect. Among European Americans, a nominally statistically significant SNP association in IL20 and an IL20 haplotype were associated with HBV recovery (P = 0.01,0.04). These results suggest that IL10 and IL20 gene variants influence HBV infection outcome and encourage the pursuit of further studies of these cytokines in HBV pathogenesis. [source] MICA-STR, HLA-B haplotypic diversity and linkage disequilibrium in the Hunan Han population of southern ChinaINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4 2006W. Tian Summary Major histocompatibility complex (MHC) class I chain-related gene A (MICA) is located 46 kb centromeric to HLA-B and encodes a stress-inducible protein. MICA allelic variation is thought to be associated with disease susceptibility and immune response to transplants. This study was aimed to investigate the haplotypic diversity and linkage disequilibrium between human leukocyte antigen (HLA)-B and (GCT)n short tandem repeat in exon 5 of MICA gene (MICA-STR) in a southern Chinese Han population. Fifty-eight randomly selected nuclear families with 183 members including 85 unrelated parental samples were collected in Hunan province, southern China. HLA-B generic typing was performed by polymerase chain reaction,sequence-specific priming (PCR,SSP), and samples showing novel HLA-B-MICA-STR linkage were further typed for HLA-B allelic variation by high-resolution PCR,SSP. MICA-STR allelic variation and MICA gene deletion (MICA*Del) were detected by fluorescent PCR,size sequencing and PCR,SSP. Haplotype was determined through family segregation analysis. Statistical analysis was applied to the data of the 85 unrelated parental samples. Nineteen HLA-B specificities and seven MICA-STR allelic variants were observed in 85 unrelated parental samples, the most predominant of which were HLA-B*46, -B60, -B*13, and -B*15, and MICA*A5, MICA*A5.1 and MICA*A4, respectively. Genotype distributions of HLA-B, MICA-STR loci were consistent with Hardy,Weinberg proportions. The HLA-B-MICA-STR haplotypic phases of all 85 unrelated parental samples were unambiguously assigned, which contained 30 kinds of HLA-B, MICA-STR haplotypic combinations, nine of them have not been reported in the literature. Significant positive linkage disequilibria between certain HLA-B and MICA-STR alleles, including HLA-B*13 and MICA*A4, HLA-B*38 and MICA*A9, HLA-B*58 and MICA*A9, HLA-B*46 and MICA*A5, HLA-B*51 and MICA*A6, HLA-B*52 and MICA*A6, and HLA-B60 and MICA*A5.1, were observed. HLA-B*48 was linked to MICA*A5, MICA*A5.1 and MICA*Del. HLA-B*5801-MICA*A10 linkage was found in a family. Our data indicated a high degree of haplotypic diversity and strong linkage disequilibrium between MICA-STR and HLA-B in a southern Chinese Han population, the data will inform future studies on anthropology, donor,recipient HLA matching in clinical transplantation and HLA-linked disease association. [source] Association of a melanocortin 4 receptor (MC4R) polymorphism with performance traits in Lithuanian White pigsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 1 2006R. Jokubka Summary The melanocortin 4 receptor is expressed in virtually all brain regions of mammals and plays an important role in energy homeostasis. Polymorphisms in this gene may thus be related to growth and obesity. In pigs, a non-synonymous polymorphic site was described (Asp298Asn) and demonstrated to affect cAMP production and to alter adenylyl cyclase signalling. Association studies revealed significant linkage of this mutation with production trait in pigs. In this study, 207 Lithuanian White pigs were genotyped at the MC4R locus and analysed on relationships between genotype and breeding values for several performance traits. The observed allele and genotype frequencies did not deviate significantly from Hardy,Weinberg equilibrium (wildtype allele 0.59; mutant allele 0.41) and are comparable with those described in other Large White populations. The mutant Asn298 allele of the MC4R gene was significantly associated with increased test daily gain, higher lean meat percentage and lower backfat thickness. There was a trend towards an improved feed conversion ratio (p = 0.065) in animals with the mutant allele whereas no significant effect was found on lifetime daily gain. These results indicate that the MC4R polymorphism should be integrated in selection programmes in the Lithuanian White to improve carcass composition. [source] Genetic variability of seven dog breeds based on microsatellite markersJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2005C. Schelling Summary The present study, compared the genetic variability of seven dog breeds and a test sample from Switzerland by means of 26 microsatellite markers. Five loci were excluded from further analyses because one was monomorphic, one not in Hardy,Weinberg equilibrium in all breeds and three in linkage disequilibrium with linked loci. The proportion of shared alleles at the individual level of the remaining 21 microsatellite markers combined with the neighbour-joining method allowed for the clustering of the large majority of the individuals in accordance to their breed. The results were confirmed by analyses using a Bayesian approach for clustering and a Monte Carlo re-sampling method for individual assignment or exclusion to a given population. [source] Microsatellites assessment of Chinese sturgeon (Acipenser sinensis Gray) genetic variabilityJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2005N. Zhao Summary Four microsatellites were used to examine the genetic variability of the spawning stocks of Chinese sturgeon, Acipenser sinensis, from the Yangtze River sampled over a 3-year period (1999,2001). Within 60 individuals, a total of 28 alleles were detected over four polymorphic microsatellite loci. The number of alleles per locus ranged from 4 to 15, with an average allele number of 7. The number of genotypes per locus ranged from 6 to 41. The genetic diversity of four microsatellite loci varied from 0.34 to 0.67, with an average value of 0.54. For the four microsatellite loci, the deviation from the Hardy,Weinberg equilibrium was mainly due to null alleles. The mean number of alleles per locus and the mean heterozygosity were lower than the average values known for anadromous fishes. Fish were clustered according to their microsatellite characteristics using an unsupervised ,Artificial Neural Networks' method entitled ,Self-organizing Map'. The results revealed no significant genetic differentiation considering genetic distance among samples collected during different years. Lack of heterogeneity among different annual groups of spawning stocks was explained by the complex age structure (from 8 to 27 years for males and 12 to 35 years for females) of Chinese sturgeon, leading to formulate an hypothesis about the maintenance of genetic diversity and stability in long-lived animals. [source] Genetic divergences pre-date Pleistocene glacial cycles in the New Zealand speckled skink, Oligosoma infrapunctatumJOURNAL OF BIOGEOGRAPHY, Issue 5 2008Stephanie N. J. Greaves Abstract Aim, To examine the hypothesis raised by Graham S. Hardy that Pleistocene glacial cycles suffice to explain divergence among lineages within the endemic New Zealand speckled skink, Oligosoma infrapunctatum Boulenger. Location, Populations were sampled from across the entire range of the species, on the North and South Islands of New Zealand. Methods, We sequenced the mitochondrial genes ND2 (550 bp), ND4 + tRNAs (773 bp) and cytochrome b (610 bp) of 45 individuals from 21 locations. Maximum likelihood, maximum parsimony and Bayesian methods were used for phylogenetic reconstruction. The Shimodaira,Hasegawa test was used to examine hypotheses about the taxonomic status of morphologically distinctive populations. Results, Our analysis revealed four strongly supported clades within O. infrapunctatum. Clades were largely allopatric, except on the west coast of the South Island, where representatives from all four clades were found. Divergences among lineages within the species were extremely deep, reaching over 5%. Two contrasting phylogeographical patterns are evident within O. infrapunctatum. Main conclusions, The deep genetic divisions we found suggest that O. infrapunctatum is a complex of cryptic species which diverged in the Pliocene, contrary to the existing Pleistocene-based hypothesis. Although Pleistocene glacial cycles do not underlie major divergences within this species, they may be responsible for the shallower phylogeographical patterns that are found within O. infrapunctatum, which include a radiation of haplotypes in the Nelson and Westland regions. [source] Aggressive periodontitis is likely influenced by a few small effect genesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2009Flavia M. De Carvalho Abstract Aim: To evaluate the inheritance mode of aggressive periodontitis in a collection of families with a similar geographic origin. Materials and Methods: Segregation analysis was performed in pedigree data from 74 families by the use of the SEGREG program of SAGE v.5.4.2. Homogeneous no transmission, homogeneous Mendelian transmission, homogeneous general transmission, semi-general transmission and heterogeneous general transmission models were tested assuming the prevalence of aggressive periodontitis as 1% and no deviations from Hardy,Weinberg equilibrium. The parameters of the model were estimated by the method of maximum likelihood, which provides the overall ln (likelihood), -2ln and the AIC (Akaike's score) for each model. The likelihood ratio test (LRT) was used to compare each model against a fully general model (p>0.05). Results: The most parsimonious mode of inheritance was the semi-general transmission model that allows the heterozygote transmission probability to vary. Conclusion: This result provides strong support for the hypothesis that genetic factors play a role in aggressive periodontitis and that a few loci, each with relatively small effects, contribute to aggressive periodontitis, with or without interaction with environmental factors. [source] Single-nucleotide polymorphisms in the IL-4 and IL-13 promoter region in aggressive periodontitisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2007J. R. Gonzales Abstract Introduction: IL-4 and IL-13 polymorphisms have been shown to influence the susceptibility to systemic diseases. In this study, possible associations between the IL-4 ,590 C,T, IL-4 ,34 C,T, IL-13 ,1112 C,T and IL-13 ,1512 A,C promoter polymorphisms were investigated in subjects with generalized aggressive periodontitis (AgP) compared with healthy individuals. Material and Methods: Fifty-eight patients with diagnosis of generalized AgP and 51 matched healthy controls participated in the study. Blood samples were collected and DNA isolated. Molecular analyses were performed by PCR-RFLP in a blind fashion. Genotype and allele frequencies among study groups were compared using Fisher's exact test (, value: 0.05). Pearson's ,2 test was used for analysis of Hardy,Weinberg equilibrium. Results: The frequency of the IL-4 ,590 T/T and IL-4 ,34 T/T genotypes differed significantly between groups (p=0.05, 0.02, respectively), although the allele frequencies were similar. There was a higher frequency of the IL-4 ,590 T/T and IL-4 ,34 T/T genotypes in patients with AgP compared with controls. The genotype and allele frequencies of the IL-13 polymorphisms did not differ between groups. Conclusions: This study demonstrated an association between the IL-4 ,590 T/T and IL-4 ,34 T/T genotypes and AgP. Further research is necessary to prove if there is an association of these polymorphisms with AgP, and if the polymorphisms have a functional effect. [source] Additive partitioning of diversity including species differences: a comment on Hardy & Senterre (2007)JOURNAL OF ECOLOGY, Issue 5 2008Sébastien Villéger Summary 1The distribution of biodiversity at multiple spatial scales has been traditionally investigated through the additive partitioning of ,-biodiversity (regional) into ,-(within-site) and ,-(among-site) components. 2However, this decomposition is almost exclusively applied using species turnover among communities while two communities with no species in common can be very similar because they share some ,biological' similarity. 3To overcome this limitation, Hardy & Senterre (2007) (J. Ecol., 95, 493,506) presented a new statistical framework partitioning the phylogenetic diversity into ,- and ,-components using the Rao's quadratic entropy. 4We show that their decomposition is correct only when sites have the same total abundance, otherwise it may lead to negative ,-diversity values. As an alternative, we provided a general decomposition of the quadratic entropy into ,-, ,- and ,-diversities. 5Synthesis. We suggest that the ,biological' turnover quantified by the ,-component of the regional quadratic entropy may help, at least, to disentangle dispersal vs. niche influences on biodiversity patterns. [source] Interpreting and estimating measures of community phylogenetic structuringJOURNAL OF ECOLOGY, Issue 5 2008Olivier J. Hardy Summary 1To characterize the spatial phylogenetic structure of communities, Hardy & Senterre (2007) (J. Ecol., 95, 493,506) partition Gini,Simpson diversity and its generalization, Rao's entropy, defining IST and PST as the proportion of diversity expressed among sites. 2Interpreting IST as a measure of ,differentiation' between sites is inadequate because low values are actually compatible with high differentiation (low species sharing) in species rich communities. To avoid an inadequate use of IST, for example in conservation biology, we offer a more literal interpretation: IST expresses the ,local species identity excess'. Similarly, PST expresses the ,local phylogenetic similarity excess'. 3Villéger & Mouillot (2008) (J. Ecol., 96, 845,848, this issue) argue that the equations of Hardy & Senterre (2007) to compute diversity are inadequate when sites differ in size, and they provide new expressions weighting sites by their sizes. We argue that whether sites must be weighted equally or not depends on the question being asked. Moreover, actual size and sample size must be distinguished, the latter being important for defining estimators. 4Synthesis. The formulations given by Hardy & Senterre (2007) and by Villéger & Mouillot (2008) are both correct in the specific contexts we detail. [source] Fitness differences associated with Pgi SNP genotypes in the Glanville fritillary butterfly (Melitaea cinxia)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2009L. ORSINI Abstract Allozyme variation at the phosphoglucose isomerase (PGI) locus in the Glanville fritillary butterfly (Melitaea cinxia) is associated with variation in flight metabolic rate, dispersal rate, fecundity and local population growth rate. To map allozyme to DNA variation and to survey putative functional variation in genomic DNA, we cloned the coding sequence of Pgi and identified nonsynonymous variable sites that determine the most common allozyme alleles. We show that these single-nucleotide polymorphisms (SNPs) exhibit significant excess of heterozygotes in field-collected population samples as well as in laboratory crosses. This is in contrast to previous results for the same species in which other allozymes and SNPs were in Hardy,Weinberg equilibrium or exhibited an excess of homozygotes. Our results suggest that viability selection favours Pgi heterozygotes. Although this is consistent with direct overdominance at Pgi, we cannot exclude the possibility that heterozygote advantage is caused by the presence of one or more deleterious alleles at linked loci. [source] Migration load in plants: role of pollen and seed dispersal in heterogeneous landscapesJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2008S. LOPEZ Abstract Evolution of local adaptation depends critically on the level of gene flow, which, in plants, can be due to either pollen or seed dispersal. Using analytical predictions and individual-centred simulations, we investigate the specific influence of seed and pollen dispersal on local adaptation in plant populations growing in patchy heterogeneous landscapes. We study the evolution of a polygenic trait subject to stabilizing selection within populations, but divergent selection between populations. Deviations from linkage equilibrium and Hardy,Weinberg equilibrium make different contributions to genotypic variance depending on the dispersal mode. Local genotypic variance, differentiation between populations and genetic load vary with the rate of gene flow but are similar for seed and pollen dispersal, unless the landscape is very heterogeneous. In this case, genetic load is higher in the case of pollen dispersal, which appears to be due to differences in the distribution of genotypic values before selection. [source] Genetic signatures in an invasive parasite of Anguilla anguilla correlate with differential stock managementJOURNAL OF FISH BIOLOGY, Issue 1 2010S. Wielgoss In this article, it is shown that available genetic tools for the omnipresent parasite Anguillicoloides crassus in European eels Anguilla anguilla are sensitive to different immigration rates into local A. anguilla stocks for two separated river systems. Relying on four highly polymorphic microsatellite markers, it was inferred that under natural recruitment, nematode samples meet Hardy,Weinberg expectations for a single panmictic population, while genetic signals show signs for a strong Wahlund effect most likely due to very recent population mixing under frequent restocking of young A. anguilla. This was indicated by a low but significant FST value among within-host populations (infrapopulations) along with high inbreeding indices FIS consistent over all loci. The latter signal is shown to stem from high levels of admixture and the presence of first-generation migrants, and alternative explanations such as marker- and sex-specific biases in the nematode populations could be dismissed. Moreover, the slightly increased degree of relatedness within infrapopulations in the stocked river system cannot explain the excessive inbreeding values found and are most likely a direct consequence of recent influx of already infected fish harbouring parasites with different genetic signatures. Applying a simulation approach using known variables from the nematode's invasion history, only the artificial introduction of a Wahlund effect leads to a close match between simulated and real data, which is a strong argument for using the parasite as a biological tag for detecting and characterizing fish translocation. [source] Matrix metalloproteinase-3 gene polymorphism in renal transplant patients with gingival overgrowthJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2010A. Drozdzik Drozdzik A, Kurzawski M, Lener A, Kozak M, Banach J, Drozdzik M. Matrix metalloproteinase-3 gene polymorphism in renal transplant patients with gingival overgrowth. J Periodont Res 2009; doi: 10.1111/j.1600-0765.2009.01221.x. © 2009 The Authors. Journal compilation © 2009 Blackwell Munksgaard Background and Objective:, Gingival enlargement frequently occurs in transplant patients receiving immunosuppressive drugs. It was hypothesized that gingival enlargement associated with cyclosporine use results from reduced degradation of extracellular matrix in the gingiva. Matrix metalloproteinase-3 (MMP-3) is involved in biodegradation of the extracellular matrix, and its inhibition may contribute to an abnormal accumulation of fibronectin and proteoglycans, which are MMP-3 substrates. The aim of this study was to investigate whether an association exists between MMP-3 genotypes and gingival enlargement in kidney transplant patients medicated with cyclosporine A. Material and Methods:, Sixty-four unrelated kidney transplant patients suffering from gingival overgrowth, as well as 111 control transplant patients without gingival overgrowth, were enrolled in the study. Gingival overgrowth was assessed 6 mo after transplantation. During the post-transplant period all patients were given cyclosporine A as a principal immunosuppressive agent. MMP-3 polymorphism was determined using a PCR restriction fragment length polymorphism assay. Results:, In kidney transplant patients suffering from gingival overgrowth the mean gingival overgrowth score was 1.35 ± 0.57, whereas in control subjects the mean gingival overgrowth score was 0.0. The distribution of MMP-3 -1178A/*dupA alleles among all kidney transplant patients, as well as in the two study subgroups, did not differ significantly from Hardy,Weinberg equilibrium. The frequency of the MMP-3-1171*A/*A genotype (28.1% for gingival overgrowth vs. 26.1% for controls) and of the MMP-3-1171*dupA/*dupA genotype (32.8% for gingival overgrowth vs. 22.5% for controls) was similar for both study groups. The risk of gingival overgrowth was lowest among patients carrying the MMP-3-1171*A/*dupA genotype (odds ratio 0.52), but this did not differ markedly from the other genotypes. Conclusion:, No association between MMP-3 gene polymorphism and gingival overgrowth was revealed in kidney transplant patients administered cyclosporine A. [source] The Elusive Importance Effect: More Failure for the Jamesian Perspective on the Importance of Importance in Shaping Self-EsteemJOURNAL OF PERSONALITY, Issue 5 2008Herbert W. MarshArticle first published online: 28 JUL 200 ABSTRACT Following William James (1890/1963), many leading self-esteem researchers continue to support the Individual-importance hypothesis,that the relation between specific facets of self-concept and global self-esteem depends on the importance an individual places on each specific facet. However, empirical support for the hypothesis is surprisingly elusive, whether evaluated in terms of an importance-weighted average model, a generalized multiple regression approach for testing self-concept-by-importance interactions, or idiographic approaches. How can actual empirical support for such an intuitively appealing and widely cited psychological principle be so elusive? Hardy and Moriarty (2006), acknowledging this previous failure of the Individual-importance hypothesis, claim to have solved the conundrum, demonstrating an innovative idiographic approach that provides clear support for it. However, a critical evaluation of their new approach, coupled with a reanalysis of their data, undermines their claims. Indeed, their data provide compelling support against the Individual-importance hypothesis, which remains as elusive as ever. [source] Thermodynamic Properties and Phase Diagram for the System MoO2,TiO2JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2008K. Thomas Jacob The activity of molybdenum dioxide (MoO2) in the MoO2,TiO2 solid solutions was measured at 1600 K using a solid-state cell incorporating yttria-doped thoria as the electrolyte. For two compositions, the emf was also measured as a function of temperature. The cell was designed such that the emf is directly related to the activity of MoO2 in the solid solution. The results show monotonic variation of activity with composition, suggesting a complete range of solid solutions between the end members and the occurrence of MoO2 with a tetragonal structure at 1600 K. A large positive deviation from Raoult's law was found. Excess Gibbs energy of mixing is an asymmetric function of composition and can be represented by the subregular solution model of Hardy as follows The temperature dependence of the emf for two compositions is reasonably consistent with ideal entropy of mixing. A miscibility gap is indicated at a lower temperature with the critical point characterized by Tc (K)=1560 and. Recent studies indicate that MoO2 undergoes a transition from a monoclinic to tetragonal structure at 1533 K with a transition entropy of 9.91 J·(mol·K),1. The solid solubility of TiO2 with rutile structure in MoO2 with a monoclinic structure is negligible. These features give rise to a eutectoid reaction at 1412 K. The topology of the computed phase diagram differs significantly from that suggested by Pejryd. [source] Lipid metabolism and occurrence of post-percutaneous transluminal coronary angioplasty restenosis: role of cholesteryl ester transfer protein and paraoxonase/arylesteraseJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2003R. Y. L. Zee Summary., Plasma lipid metabolic and transfer processes have recently been suggested to play an important role in the development of early restenosis, a major complication of percutaneous transluminal coronary angioplasty (PTCA); in particular, the common variants of genes for cholesteryl ester transfer protein (CETP) and paraoxonase (PONA) have been implicated. We had the opportunity to investigate this question in a large, prospective cohort characterized by quantitative coronary angiography in all subjects. The CETP-TaqIB (intron 1), CETP-MspI (intron 8), and PONA-AlwI (exon 2) polymorphisms were characterized in a cohort of 779 patients of whom 342 (,cases') had developed restenosis (as defined by >,50% loss of lumen compared with immediate postprocedure results) at repeat angiography at 6 months post PTCA. Selected frequencies for CETP B1 and B2 alleles (absence/presence of TaqIB site) were 0.65 and 0.35 (cases) and 0.65 and 0.35 (controls), respectively; frequencies for CETP M1 and M2 alleles (absence/presence of MspI site) were 0.20 and 0.80 (cases), 0.21 and 0.79 (controls), respectively; frequencies for PONA A and B alleles (absence/presence of AlwI site) were 0.73 and 0.27 (cases), 0.72 and 0.28 (controls), respectively. All observed genotype frequencies were in Hardy,Weinberg equilibrium. There was no evidence for gene,gene interaction, or an association between genotype and restenosis or degree of lumen loss (adjusted for covariates). Our data, collected in the largest study of its kind so far, indicate that the common variants for CETP and PONA are not associated with incidence of restenosis after PTCA, and are therefore not useful markers for risk assessment. [source] Genetic variability and population structure of dorada (Brycon moorei sinuensis Dahl) in the Sinú River, Córdoba, ColombiaLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 1 2006Liliana López Abstract Six microsatellite loci, isolated for Piaractus mesopotamicus (Characidae, Serrasalminae) were used to evaluate the genetic variability of the dorada (Brycon moorei sinuensis, Characidae, Bryconinae) population in the Sinú River, Córdoba, Colombia, and to facilitate management recommendations for this species. The six loci were polymorphic, with an average of 9.25 alleles for dimeric loci (Pme2, Pme4, Pme5 and Pme20), and five alleles for trimeric loci. Tests for linkage disequilibrium were used to determine that the six loci had an independent distribution. The observed heterozygosities were lower than the expected ones for all loci, and the population was not in Hardy,Weinberg equilibrium because of heterozygote deficiency. F -statistics indicated inbreeding and a low population substructure. The homogeneity of the population was confirmed by high values of genetic flux and an agglomerated representation of the individuals, based on factor correspondence analysis. Recent bottlenecks were detected for three sample sites under the assumption of an infinite allele mutation model. Proposals for the management of the dorada population are made and validated with a genetic simulation. [source] Singular integral operator, Hardy,Morrey space estimates for multilinear operators and Navier,Stokes equationsMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 14 2010Henggeng Wang Abstract After establishing the molecule characterization of the Hardy,Morrey space, we prove the boundedness of the singular integral operator and the Riesz potential. We also obtain the Hardy,Morrey space estimates for multilinear operators satisfying certain vanishing moments. As an application, we study the existence and the uniqueness of the solutions to the Navier,Stokes equations for the initial data in the Hardy,Morrey space ,,(p,n) for q as small as possible. Here, the Hardy,Morrey space estimates for multilinear operators are important tools. Copyright © 2010 John Wiley & Sons, Ltd. [source] Herz spaces and summability of Fourier transformsMATHEMATISCHE NACHRICHTEN, Issue 3 2008Hans G. Feichtinger Abstract A general summability method is considered for functions from Herz spaces K,p,r (,d). The boundedness of the Hardy,Littlewood maximal operator on Herz spaces is proved in some critical cases. This implies that the maximal operator of the , -means ,,Tf is also bounded on the corresponding Herz spaces and ,,Tf , f a.e. for all f , K,d /pp,, (,d). Moreover, ,,Tf (x) converges to f (x) at each p -Lebesgue point of f , K,d /pp,, (,d) if and only if the Fourier transform of , is in the Herz space Kd /pp ,,1 (,d). Norm convergence of the , -means is also investigated in Herz spaces. As special cases some results are obtained for weighted Lp spaces. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] On Hardy,Steklov and geometric Steklov operatorsMATHEMATISCHE NACHRICHTEN, Issue 11 2007V. Burenkov Abstract A new (non-Muckenhoupt type) weight characterization for the boundedness of the general Hardy,Steklov operator is obtained in the case 1 < p , q < ,. The estimates obtained for the norm of the Hardy,Steklov operator allow the limiting procedure and as a result the boundedness of the corresponding geometric Steklov operator is investigated. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] On a semilinear elliptic equation with singular term and Hardy,Sobolev critical growthMATHEMATISCHE NACHRICHTEN, Issue 8 2007Jianqing ChenArticle first published online: 8 MAY 200 Abstract In a previous work [6], we got an exact local behavior to the positive solutions of an elliptic equation. With the help of this exact local behavior, we obtain in this paper the existence of solutions of an equation with Hardy,Sobolev critical growth and singular term by using variational methods. The result obtained here, even in a particular case, relates with a partial (positive) answer to an open problem proposed in: A. Ferrero and F. Gazzola, Existence of solutions for singular critical growth semilinear elliptic equations, J. Differential Equations 177, 494,522 (2001). (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Parametrized Littlewood,Paley operators on Hardy and weak Hardy spacesMATHEMATISCHE NACHRICHTEN, Issue 4 2007Yong Ding Abstract In this paper, we give the boundedness of the parametrized Littlewood,Paley function on the Hardy spaces and weak Hardy spaces. As the corollaries of the above results, we prove that is of weak type (1, 1) and of type (p, p) for 1 < p < 2, respectively. This results are substantial improvement and extension of some known results. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Spatio-temporal variation in the strength and mode of selection acting on major histocompatibility complex diversity in water vole (Arvicola terrestris) metapopulationsMOLECULAR ECOLOGY, Issue 1 2009MATTHEW K. OLIVER Abstract Patterns of spatio-temporal genetic variation at a class II major histocompatibility complex (MHC) locus and multiple microsatellite loci were analysed within and between three water vole metapopulations in Scotland, UK. Comparisons of MHC and microsatellite spatial genetic differentiation, based on standardised tests between two demographically asynchronous zones within a metapopulation, suggested that spatial MHC variation was affected by balancing selection, directional selection and random genetic drift, but that the relative effects of these microevolutionary forces vary temporally. At the metapopulation level, between-year differentiation for MHC loci was significantly correlated with that of microsatellites, signifying that neutral factors such as migration and drift were primarily responsible for overall temporal genetic change at the metapopulation scale. Between metapopulations, patterns of genetic differentiation implied that, at large spatial scales, MHC variation was primarily affected by directional selection and drift. Levels of MHC heterozygosity in excess of Hardy,Weinberg expectations were consistent with overdominant balancing selection operating on MHC variation within metapopulations. However, this effect was not constant among all samples, indicating temporal variation in the strength of selection relative to other factors. The results highlight the benefit of contrasting variation at MHC with neutral markers to separate the effects of stochastic and deterministic microevolutionary forces, and add to a growing body of evidence showing that the mode and relative strength of selection acting on MHC diversity varies both spatially and temporally. [source] | ||||||||||||||||||||||