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Sample records for gene frequency

  1. Metabolic gene polymorphism frequencies in control populations

    DEFF Research Database (Denmark)

    Garte, Seymour; Gaspari, Laura; Alexandrie, Anna-Karin

    2001-01-01

    Using the International Project on Genetic Susceptibility to Environmental Carcinogens (GSEC) database containing information on over 15,000 control (noncancer) subjects, the allele and genotype frequencies for many of the more commonly studied metabolic genes (CYP1A1, CYP2E1, CYP2D6, GSTM1, GSTT...

  2. Comparison of somatic mutation frequency among immunoglobulin genes.

    Science.gov (United States)

    Motoyama, N; Miwa, T; Suzuki, Y; Okada, H; Azuma, T

    1994-02-01

    We analyzed the frequency of somatic mutation in immunoglobulin genes from hybridomas that secrete anti-(4-hydroxy-3-nitrophenyl)acetyl (NP) monoclonal antibodies. A high frequency of mutation (3.3-4.4%) was observed in both the rearranged VH186.2 and V lambda 1 genes, indicating that somatic mutation occurs with similar frequency in these genes in spite of the absence of an intron enhancer in lambda 1 chain genes. In contrast to the high frequency in J-C introns, only two nucleotide substitutions occurred at positions -462 and -555 in the 5' noncoding region in one of the lambda 1-chain genes and in none of the other three so far studied. Since a similar low frequency of somatic mutation was observed in the 5' noncoding region of inactive lambda 2-chain genes rendered inactive because of incorrect rearrangement, this region may not be a target or alternatively, may be protected from the mutator system. We observed a low frequency of nucleotide substitution in unrearranged V lambda 1 genes (approximately 1/15 that of rearranged genes). Together with previous results (Azuma T., N. Motoyama, L. Fields, and D. Loh, 1993. Int. Immunol. 5:121), these findings suggest that the 5' noncoding region, which contains the promoter element, provides a signal for the somatic mutator system and that rearrangement, which brings the promoter into close proximity to the enhancer element, should increase mutation efficiency.

  3. Many levels of control of V gene rearrangement frequency.

    Science.gov (United States)

    Feeney, Ann J; Goebel, Peter; Espinoza, Celia R

    2004-08-01

    V, D, and J gene segments rearrange at very different frequencies. As with most biological systems, there are multiple levels of control of V gene recombination frequency, and here we review some of the work from our laboratory that addresses these various control mechanisms. One of the important factors that affect non-random V gene rearrangement frequency is the natural heterogeneity in recombination signal sequences (RSSs). Not only does variation in the heptamer and nonamer affect rearrangement, but variation in the spacer can also dramatically affect recombination. However, there are clearly other factors which control V gene rearrangement, as revealed by the fact that genes with identical RSSs can rearrange at different frequencies in vivo. Some of these other influences most likely affect the earliest stages of control--the change from an inaccessible state to an accessible state. Transcription factors can play a role in inducing these changes. Rearrangement of many VkappaI genes can be induced in a non-lymphoid cell line after ectopic expression of E2A, while neighboring VkappaII and VkappaIII genes do not rearrange, demonstrating that at least one level of control of induction of accessibility occurs at the level of the individual gene. Also, changes in chromatin structure can affect accessibility and might influence individual V gene rearrangement frequency.

  4. Gaucher disease: Gene frequencies in the Ashkenazi Jewish population

    Energy Technology Data Exchange (ETDEWEB)

    Beutler, E.; West, C.; Gelbart, T. (Scripps Research Inst., La Jolla, CA (United States)); Nguyen, N.J.; Henneberger, M.W.; Smolec, J.M.; McPherson, R.A. (Scripps Immunology Reference Lab., San Diego, CA (United States))

    1993-01-01

    DNA from over 2,000 Ashkenazi Jewish subjects has been examined for the four most common Jewish Gaucher disease mutations, which collectively account for about 96% of the disease-producing alleles in Jewish patients. This population survey has made possible the estimation of gene frequencies for these alleles. Eighty-seven of 1,528 individuals were heterozygous for the 1226G (N370S) mutation, and four presumably well persons were homozygous for this mutation. The gene frequency for the 1226G allele was calculated to be .0311, and when these data were pooled with those obtained previously from another 593 Jewish subjects, a gene frequency of .032 with a standard error of .004 was found. Among 2,305 normal subjects, 10 were found to be heterozygous for the 84GG allele, giving a gene frequency of .00217 with a standard error of .00096. No examples of the IVS2(+1) mutation were found among 1,256 samples screened, and no 1448C (L444P) mutations were found among 1,528 samples examined. Examination of the distribution of Gaucher disease gene frequencies in the general population shows that the ratio of 1226G mutations to 84GG mutations is higher than that in the patient population. This is presumed to be due to the fact that homozygotes for the 1226G mutation often have late-onset disease or no significant clinical manifestations at all. To bring the gene frequency in the patient population into conformity with the gene frequency in the general population, nearly two-thirds of persons with a Gaucher disease genotype would be missing from the patient population, presumably because their clinical manifestations were very mild. 10 refs., 3 tabs.

  5. Frequency domain analysis of noise in autoregulated gene circuits

    OpenAIRE

    Simpson, Michael L.; Cox, Chris D.; Sayler, Gary S.

    2003-01-01

    We describe a frequency domain technique for the analysis of intrinsic noise within negatively autoregulated gene circuits. This approach is based on the transfer function around the feedback loop (loop transmission) and the equivalent noise bandwidth of the system. The loop transmission, T, is shown to be a determining factor of the dynamics and the noise behavior of autoregulated gene circuits, and this T-based technique provides a simple and flexible method for the analysis of noise arisin...

  6. Frequency domain analysis of noise in autoregulated gene circuits

    Science.gov (United States)

    Simpson, Michael L.; Cox, Chris D.; Sayler, Gary S.

    2003-01-01

    We describe a frequency domain technique for the analysis of intrinsic noise within negatively autoregulated gene circuits. This approach is based on the transfer function around the feedback loop (loop transmission) and the equivalent noise bandwidth of the system. The loop transmission, T, is shown to be a determining factor of the dynamics and the noise behavior of autoregulated gene circuits, and this T-based technique provides a simple and flexible method for the analysis of noise arising from any source within the gene circuit. We show that negative feedback not only reduces the variance of the noise in the protein concentration, but also shifts this noise to higher frequencies where it may have a negligible effect on the noise behavior of following gene circuits within a cascade. This predicted effect is demonstrated through the exact stochastic simulation of a two-gene cascade. The analysis elucidates important aspects of gene circuit structure that control functionality, and may provide some insights into selective pressures leading to this structure. The resulting analytical relationships have a simple form, making them especially useful as synthetic gene circuit design equations. With the exception of the linearization of Hill kinetics, this technique is general and may be applied to the analysis or design of networks of higher complexity. This utility is demonstrated through the exact stochastic simulation of an autoregulated two-gene cascade operating near instability. PMID:12671069

  7. Transferrin gene frequencies in Cádiz (southern Spain).

    Science.gov (United States)

    Gamero, J J; Romero, J L; Vizcaya, M A; Arufe, I

    1990-12-01

    The genetic polymorphism of transferrin (Tf) was studied in a sample of 385 healthy unrelated subjects of both sexes resident in the province of Cádiz (southern Spain). Isoelectric focusing was carried out in polyacrylamide gels, followed by staining with Coomassie Blue R250. The gene frequencies obtained were as follows: Tf C1, 0.7922; Tf C2, 0.1883; Tf C3, 0.0195.

  8. A gene frequency model for QTL mapping using Bayesian inference

    Directory of Open Access Journals (Sweden)

    Dekkers Jack CM

    2010-06-01

    Full Text Available Abstract Background Information for mapping of quantitative trait loci (QTL comes from two sources: linkage disequilibrium (non-random association of allele states and cosegregation (non-random association of allele origin. Information from LD can be captured by modeling conditional means and variances at the QTL given marker information. Similarly, information from cosegregation can be captured by modeling conditional covariances. Here, we consider a Bayesian model based on gene frequency (BGF where both conditional means and variances are modeled as a function of the conditional gene frequencies at the QTL. The parameters in this model include these gene frequencies, additive effect of the QTL, its location, and the residual variance. Bayesian methodology was used to estimate these parameters. The priors used were: logit-normal for gene frequencies, normal for the additive effect, uniform for location, and inverse chi-square for the residual variance. Computer simulation was used to compare the power to detect and accuracy to map QTL by this method with those from least squares analysis using a regression model (LSR. Results To simplify the analysis, data from unrelated individuals in a purebred population were simulated, where only LD information contributes to map the QTL. LD was simulated in a chromosomal segment of 1 cM with one QTL by random mating in a population of size 500 for 1000 generations and in a population of size 100 for 50 generations. The comparison was studied under a range of conditions, which included SNP density of 0.1, 0.05 or 0.02 cM, sample size of 500 or 1000, and phenotypic variance explained by QTL of 2 or 5%. Both 1 and 2-SNP models were considered. Power to detect the QTL for the BGF, ranged from 0.4 to 0.99, and close or equal to the power of the regression using least squares (LSR. Precision to map QTL position of BGF, quantified by the mean absolute error, ranged from 0.11 to 0.21 cM for BGF, and was better

  9. Principal component analysis of gene frequencies of Chinese populations

    Institute of Scientific and Technical Information of China (English)

    肖春杰; L.L.Cavalli-Sforza; E.Minch; 杜若甫

    2000-01-01

    Principal components (PCs) were calculated based on gene frequencies of 130 alleles at 38 loci in Chinese populations, and geographic PC maps were constructed. The first PC map of the Han shows the genetic difference between Southern and Northern Mongoloids, while the second PC indicates the gene flow between Caucasoid and Mongoloids. The first PC map of the Chinese ethnic minorities is similar to that of the second PC map of the Han, while their second PC map is similar to the first PC map of the Han. When calculating PC with the gene frequency data from both the Han and ethnic minorities, the first and second PC maps most resemble those of the ethnic minorities alone. The third and fourth PC maps of Chinese populations may reflect historical events that allowed the expansion of the populations in the highly civilized regions. A clear-cut boundary between Southern and Northern Mongoloids in the synthetic map of the Chinese populations was observed in the zone of the Yangtze River. We suggest that the a

  10. Principal component analysis of gene frequencies of Chinese populations

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Principal components (PCs) were calculated based on gene frequencies of 130 alleles at 38 loci in Chinese populations, and geographic PC maps were constructed. The first PC map of the Han shows the genetic difference between Southern and Northern Mongoloids, while the second PC indicates the gene flow between Caucasoid and Mongoloids. The first PC map of the Chinese ethnic minorities is similar to that of the second PC map of the Han, while their second PC map is similar to the first PC map of the Han. When calculating PC with the gene frequency data from both the Han and ethnic minorities, the first and second PC maps most resemble those of the ethnic minorities alone. The third and fourth PC maps of Chinese populations may reflect historical events that allowed the expansion of the populations in the highly civilized regions. A clear-cut boundary between Southern and Northern Mongoloids in the synthetic map of the Chinese populations was observed in the zone of the Yangtze River. We suggest that the ancestors of Southern and Northern Mongoloids had already separated before reaching Asia. The ancestors of the Southern Mongoloids may result from the initial expansion from Africa or the Middle East, via the south coast of Asia, toward Southeast Asia, and ultimately South China. Upon reaching the Yangtze River, they might even have crossed the river to occupy the nearby regions for a period of time. The ancestors of the Northern Mongoloids probably expanded from Africa via the Northern Pamirs, first went eastward, then towards the south to reach the Yangtze River. The expansion of the Northern Mongoloids toward the south of the Yangtze River happened only in the last 2 or 3 thousand years.

  11. Gene Frequency and Heritability of Rh Blood Group Gene in 44 Human Populations

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    Supriyo CHAKRABORTY

    2010-09-01

    Full Text Available The frequency of RhD and Rhd alleles of Rh blood group gene was estimated in 44 human populations distributed all over the world from the RhD phenotypic data. The average frequency of RhD and Rhd allele over these populations was 0.70 and 0.30, respectively. Higher frequency of RhD allele than the expected estimate (0.50 in all the populations, under Hardy-Weinberg equilibrium condition assuming equal frequency of both alleles in the initial population, indicated inbreeding at RhD/d locus as well as natural selection for RhD allele. Very high heritability estimate (84.04% of Rh allele frequency revealed that this trait was under weak selection pressure and resulted in greater genetic variation in existing populations. It is consistent with Fishers fundamental theorem of natural selection. The results from the present study suggest that inbreeding at RhD/d locus and some other factors (possibly mutation, migration and genetic drift other than natural selection alone played major roles in changing the Rh allele frequency in these populations.

  12. Gene frequencies and admixture estimates in four Mexican urban centers.

    Science.gov (United States)

    Lisker, R; Ramirez, E; Briceño, R P; Granados, J; Babinsky, V

    1990-12-01

    We studied 202 individuals from the city of Leon in Guanajuato state, 228 from Merida, Yucatan, 220 from Oaxaca, Oaxaca, and 257 from Saltillo, Coahuila, to learn the distribution of the ABO, MN, Rh, and Duffy blood groups, serum haptoglobin, albumin, and factor Bf types, and red cell hemoglobin and glucose-6-phosphate dehydrogenase types. With the gene frequencies obtained, we performed admixture measurements with a maximum likelihood method, obtaining a trihybrid model for black, Indian, and white ancestry with the following proportions: 0.084, 0.513, and 0.403 in Leon: 0.059, 0.512, and 0.429 in Merida; 0.018, 0.676, and 0.306 in Oaxaca; and 0.073, 0.547, and 0.380 in Saltillo. The general pattern has high Indian ancestry followed by white and black ancestry. This pattern is congruent with most other studies performed in Mexico, including the east coast, where Indian ancestry predominates despite a clear increase in the black contribution.

  13. Nursing frequency alters circadian patterns of mammary gene expression in lactating mice

    Science.gov (United States)

    Milking frequency impacts lactation in dairy cattle and in rodent models of lactation. The role of circadian gene expression in this process is unknown. The hypothesis tested was that changing nursing frequency alters the circadian patterns of mammary gene expression. Mid-lactation CD1 mice were stu...

  14. Genotypic frequency of calpastatin gene in lori sheep by polymerase ...

    African Journals Online (AJOL)

    SAM

    2014-05-07

    May 7, 2014 ... meat. Genomic DNA was extracted from 100 sheep blood sample. Polymerase chain ... The effect of calpains gene polymorphism on ... dation and meat tenderness after slaughter. Increased ... to -20°C freezer. Genomic DNA ...

  15. Influence of human leukocyte antigen genes on TCR V gene segment frequencies.

    Science.gov (United States)

    Genevée, C; Farace, F; Chung, V; Diu, A; Raffoux, C; Charron, D; Hercend, T; Triebel, F

    1994-10-01

    Human leukocyte antigen (HLA)-dependent selection mechanisms exerted during thymic maturation are supposed to be main contributing factors to the genetic predetermination of the TCR repertoire and may have a detectable effect on adult peripheral blood lymphocyte V segment frequencies. Here, we analyzed whether polymorphic or non-polymorphic HLA determinants are associated with selected expression of some V gene segment specificities. We first examined the reactivity of 17 V segment specific mAb on purified CD4+ and CD8+ cell fractions in 10 unrelated people. We found a significant overexpression of only three V segment products (V beta 2, V beta 5.1 and V beta 6.7) in CD4+ and none in CD8+ cell fractions in most individuals. Skewing of certain V beta segments by non-polymorphic HLA determinants (i.e. class II for CD4+ and class I for CD8+ cells) is therefore more limited (3/17) than previously thought. Considering the effects of polymorphic HLA determinants, we compared TCR V segment frequencies in HLA-identical siblings to sibling pairs who differ at one or both HLA haplotypes, using 13 V beta specific mAb. In pairwise comparisons, we found that the HLA complex had no detectable effect on TCR repertoire in five large families with multiple siblings. Together, these observations suggest that HLA-predicted selection mechanisms exerted during thymic maturation might not have a predominant influence shaping the TCR repertoire of normal adults.

  16. Prion protein gene frequencies in three Sicilian dairy sheep populations

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    Santo Caracappa

    2010-01-01

    Full Text Available The objective of this paper was to investigate the prion protein (PrP genotype and haplotype frequencies in three Sicilian dairy sheep populations. The three populations were: (1 1096 Valle del Belice animals, (2 1143 Comisana animals, and (3 1771 individuals from 5 flocks with scrapie outbreaks, in which the animals were crossbreds derived from indigenous Sicilian dairy breeds. PrP genotypes are described for the three codons 136 (Alanine or Valine; A, V, 154 (Histidine or Arginine; H, R, and 171 (Glutamine, Arginine or Histidine; Q, R, H which represent polymorphisms known to be linked with scrapie susceptibility. The Valle del Belice haplotype frequencies were 32.3% ARR, 6.5% AHQ, 1.0% ARH, 58.8% ARQ, and 1.4% VRQ. The Comisana frequencies were 39.4% ARR, 2.9% AHQ, 2.9% ARH, 50.9% ARQ, and 3.9% VRQ. In the flocks with scrapie outbreaks the frequencies were 32.8% ARR, 2.4% AHQ, 1.7% ARH, 59.1% ARQ, and 3.9% VRQ. In all three populations ARQ and ARR were the most frequent haplotypes. Multiple generations of strong selection will be needed to fixate the most resistant ARR haplotype.

  17. Genotypic frequency of calpastatin gene in lori sheep by polymerase ...

    African Journals Online (AJOL)

    ... consequently the balance of calpain-calpastatin activity in muscles is believed to dictate the rate of tenderization in post-mortem meat. ... Polymerase chain reaction was performed to amplify a 622 bp fragment of this gene. Restriction reaction of polymerase chain reaction (PCR) products was done using MspI enzyme.

  18. A₁A₂BO and Rh gene frequencies among six populations of Jammu and Kashmir, India.

    Science.gov (United States)

    Fareed, Mohd; Hussain, Ruqaiya; Shah, Ahsana; Afzal, Mohammad

    2014-04-01

    A study was undertaken to record gene frequencies of ABO blood groups, their subtypes and Rh antigen for six different endogamous groups including a tribal population. The ABO phenotypic frequency varies among six different populations showing significant difference (pI(B)>I(A1)>I(A2), except Syeds (I(O)>I(A1)>I(B)>I(A2)). The rhesus protein (Rh) phenotypic frequency (pKashmir.

  19. Detection of horizontal transfer of individual genes by anomalous oligomer frequencies

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    Elhai Jeff

    2012-06-01

    Full Text Available Abstract Background Understanding the history of life requires that we understand the transfer of genetic material across phylogenetic boundaries. Detecting genes that were acquired by means other than vertical descent is a basic step in that process. Detection by discordant phylogenies is computationally expensive and not always definitive. Many have used easily computed compositional features as an alternative procedure. However, different compositional methods produce different predictions, and the effectiveness of any method is not well established. Results The ability of octamer frequency comparisons to detect genes artificially seeded in cyanobacterial genomes was markedly increased by using as a training set those genes that are highly conserved over all bacteria. Using a subset of octamer frequencies in such tests also increased effectiveness, but this depended on the specific target genome and the source of the contaminating genes. The presence of high frequency octamers and the GC content of the contaminating genes were important considerations. A method comprising best practices from these tests was devised, the Core Gene Similarity (CGS method, and it performed better than simple octamer frequency analysis, codon bias, or GC contrasts in detecting seeded genes or naturally occurring transposons. From a comparison of predictions with phylogenetic trees, it appears that the effectiveness of the method is confined to horizontal transfer events that have occurred recently in evolutionary time. Conclusions The CGS method may be an improvement over existing surrogate methods to detect genes of foreign origin.

  20. Estimating the Frequency of Horizontal Gene Transfer Using Phylogenetic Models of Gene Gain and Loss.

    Science.gov (United States)

    Zamani-Dahaj, Seyed Alireza; Okasha, Mohamed; Kosakowski, Jakub; Higgs, Paul G

    2016-07-01

    We analyze patterns of gene presence and absence in a maximum likelihood framework with rate parameters for gene gain and loss. Standard methods allow independent gains and losses in different parts of a tree. While losses of the same gene are likely to be frequent, multiple gains need to be considered carefully. A gene gain could occur by horizontal transfer or by origin of a gene within the lineage being studied. If a gene is gained more than once, then at least one of these gains must be a horizontal transfer. A key parameter is the ratio of gain to loss rates, a/v We consider the limiting case known as the infinitely many genes model, where a/v tends to zero and a gene cannot be gained more than once. The infinitely many genes model is used as a null model in comparison to models that allow multiple gains. Using genome data from cyanobacteria and archaea, it is found that the likelihood is significantly improved by allowing for multiple gains, but the average a/v is very small. The fraction of genes whose presence/absence pattern is best explained by multiple gains is only 15% in the cyanobacteria and 20% and 39% in two data sets of archaea. The distribution of rates of gene loss is very broad, which explains why many genes follow a treelike pattern of vertical inheritance, despite the presence of a significant minority of genes that undergo horizontal transfer. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. High frequency of phylogenetically diverse reductive dehalogenase-homologous genes in deep subseafloor sedimentary metagenomes

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    Kawai, Mikihiko; Futagami, Taiki; Toyoda, Atsushi; Takaki, Yoshihiro; Nishi, Shinro; Hori, Sayaka; Arai, Wataru; Tsubouchi, Taishi; Morono, Yuki; Uchiyama, Ikuo; Ito, Takehiko; Fujiyama, Asao; Inagaki, Fumio; Takami, Hideto

    2014-01-01

    Marine subsurface sediments on the Pacific margin harbor diverse microbial communities even at depths of several hundreds meters below the seafloor (mbsf) or more. Previous PCR-based molecular analysis showed the presence of diverse reductive dehalogenase gene (rdhA) homologs in marine subsurface sediment, suggesting that anaerobic respiration of organohalides is one of the possible energy-yielding pathways in the organic-rich sedimentary habitat. However, primer-independent molecular characterization of rdhA has remained to be demonstrated. Here, we studied the diversity and frequency of rdhA homologs by metagenomic analysis of five different depth horizons (0.8, 5.1, 18.6, 48.5, and 107.0 mbsf) at Site C9001 off the Shimokita Peninsula of Japan. From all metagenomic pools, remarkably diverse rdhA-homologous sequences, some of which are affiliated with novel clusters, were observed with high frequency. As a comparison, we also examined frequency of dissimilatory sulfite reductase genes (dsrAB), key functional genes for microbial sulfate reduction. The dsrAB were also widely observed in the metagenomic pools whereas the frequency of dsrAB genes was generally smaller than that of rdhA-homologous genes. The phylogenetic composition of rdhA-homologous genes was similar among the five depth horizons. Our metagenomic data revealed that subseafloor rdhA homologs are more diverse than previously identified from PCR-based molecular studies. Spatial distribution of similar rdhA homologs across wide depositional ages indicates that the heterotrophic metabolic processes mediated by the genes can be ecologically important, functioning in the organic-rich subseafloor sedimentary biosphere. PMID:24624126

  2. Accurate assessment of intragenic recombination frequency within the Duchenne muscular dystrophy gene.

    Science.gov (United States)

    Abbs, S; Roberts, R G; Mathew, C G; Bentley, D R; Bobrow, M

    1990-08-01

    Polymorphic loci that lie at the two extremities of the Duchenne/Becker muscular dystrophy (DMD/BMD) gene have been used to estimate intragenic recombination rates. Multipoint linkage analysis of the CEPH panel of families suggests a total intragenic recombination frequency of nearly 0.12 (confidence intervals 0.041-0.226) over the genomic length of approximately 2 Mb.

  3. DNA repair gene polymorphisms in relation to chromosome aberration frequencies in retired radiation workers

    Energy Technology Data Exchange (ETDEWEB)

    Wilding, Craig S. [Genetics Department, Westlakes Research Institute, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3JY (United Kingdom)]. E-mail: craig.wilding@westlakes.ac.uk; Relton, Caroline L. [Genetics Department, Westlakes Research Institute, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3JY (United Kingdom); Paediatric and Lifecourse Epidemiology Research Group, School of Clinical Medical Sciences (Child Health), Newcastle University, Sir James Spence Institute, Royal Victoria Infirmary, Newcastle-upon-Tyne NE1 4LP (United Kingdom); Rees, Gwen S. [Genetics Department, Westlakes Research Institute, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3JY (United Kingdom); Tarone, Robert E. [International Epidemiology Institute, 1455 Research Boulevard, Suite 550, Rockville, MD 20850 (United States); Whitehouse, Caroline A. [Genetics Department, Westlakes Research Institute, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3JY (United Kingdom); Tawn, E. Janet [Genetics Department, Westlakes Research Institute, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3JY (United Kingdom)

    2005-02-15

    Polymorphic variation in DNA repair genes was examined in a group of retired workers from the British Nuclear Fuels plc facility at Sellafield in relation to previously determined translocation frequencies in peripheral blood lymphocytes. Variation at seven polymorphisms in four genes involved in the base excision repair (XRCC1 R194W, R399Q and a [AC]{sub n} microsatellite in the 3' UTR) and double strand break repair (XRCC3 T241M and a [AC]{sub n} microsatellite in intron 3 of XRCC3, XRCC4 I134T, and a GACTAn microsatellite located 120kb 5' of XRCC5) pathways was determined for 291 retired radiation workers who had received cumulative occupational external radiation doses of between 0 and 1873mSv. When the interaction between radiation dose and each DNA repair gene polymorphism was examined in relation to translocation frequency there was no evidence for any of the polymorphisms studied influencing the response to occupational exposure. A positive interaction observed between genotype (individuals with at least one allele >=20 repeat units) at a microsatellite locus in the XRCC3 gene and smoking status should be interpreted cautiously because interactions were investigated for seven polymorphisms and two exposures. Nonetheless, further research is warranted to examine whether this DNA repair gene variant might be associated with a sub-optimal repair response to smoking-induced DNA damage and hence an increased frequency of translocations.

  4. Frequencies of single nucleotide polymorphisms in genes regulating inflammatory responses in a community-based population

    Directory of Open Access Journals (Sweden)

    Comstock George W

    2007-03-01

    Full Text Available Abstract Background Allele frequencies reported from public databases or articles are mostly based on small sample sizes. Differences in genotype frequencies by age, race and sex have implications for studies designed to examine genetic susceptibility to disease. In a community-based cohort of 9,960 individuals, we compared the allele frequencies of 49 single nucleotide polymorphisms (SNPs of genes involved in inflammatory pathways to the frequencies reported on public databases, and examined the genotypes frequencies by age and sex. The genes in which SNPs were analyzed include CCR2, CCR5, COX1, COX2, CRP, CSF1, CSF2, IFNG, IL1A, IL1B, IL2, IL4, IL6, IL8, IL10, IL13, IL18, LTA, MPO, NOS2A, NOS3, PPARD, PPARG, PPARGC1 and TNF. Results Mean(SD age was 53.2(15.5; 98% were Caucasians and 62% were women. Only 1 out of 33 SNPs differed from the SNP500Cancer database in allele frequency by >10% in Caucasians (n = 9,831, whereas 12 SNPs differed by >10% (up to 50% in African Americans (n = 105. Two out of 15 SNPs differed from the dbSNP database in allele frequencies by >10% in Caucasians, and 5 out of 15 SNPs differed by >10% in African Americans. Age was similar across most genotype groups. Genotype frequencies did not differ by sex except for TNF(rs1799724, IL2(rs2069762, IL10(rs1800890, PPARG(rs1801282, and CRP(rs1800947 with differences of less than 4%. Conclusion When estimating the size of samples needed for a study, particularly if a reference sample is used, one should take into consideration the size and ethnicity of the reference sample. Larger sample size is needed for public databases that report allele frequencies in non-Caucasian populations.

  5. Evaluation of frequency of kirsten rat sarcoma gene mutations in Iranian colorectal cancer

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    Fatemeh Roudbari

    2016-09-01

    Full Text Available Background: Kirsten rat sarcoma (KRAS gene is a target of genetic alterations which are diagnostic and prognostic biomarkers in patients with metastatic colorectal cancer who are treated with monoclonal anti-EGFR antibodies such as cetuximab and panitumumab. KRAS mutations are seen in 35-42% of patients with colorectal cancer. The high frequency of these mutations in colorectal cancer represents their high potential as a biomarker in early diagnosis of cancer. This study was done to evaluate the frequency of KRAS gene mutations in a small population of Iranian patients suffering from colorectal cancer.   Methods: 50 formalin-fixed paraffin-embedded tissue blocks with colorectal cancer (CRC, already confirmed by histopathology and immunohistochemistry testing, were received to Payvand Clinical and Specialty Laboratory, Tehran, from across the country in 2015. DNA was extracted from the tissue blocks and its quality was then evaluated. The reverse dot blotting method was used to evaluate KRAS gene mutations. Results: KRAS mutations were found in 42% of the study patients. 30% and 12% of the mutations were found in codon 12 and codon 13, respectively. Moreover, no mutation was found in codon 61. Results also showed that the most frequency of samples examined belonged to male with 68% (average age of 56 years old and then to female with 32% (median age of 54.8 years old. Conclusion: This study was performed to evaluate the frequency of KRAS gene mutations in Iranian colorectal cancer patients. According to the study results, the frequency of KRAS mutations was consistent with that of other countries, reported in previous studies. The high prevalence of these mutations in patients with colorectal cancer indicates the important role of these genes in this group of patients. Thus, the presence of these mutations can be used as a suitable biomarker for evaluation of response to targeted therapies in patients suffering from colorectal cancer.

  6. Frequency and character of alternative somatic recombination fates of paralogous genes during T-DNA integration.

    Science.gov (United States)

    Jelesko, John G; Carter, Kristy; Kinoshita, Yuki; Gruissem, Wilhelm

    2005-09-01

    A synthetic RBCSB gene cluster was transformed into Arabidopsis in order to simultaneously evaluate the frequency and character of somatic illegitimate recombination, homologous recombination, and targeted gene replacement events associated with T-DNA-mediated transformation. The most frequent type of recombination event observed was illegitimate integration of the T-DNA without activation of the silent DeltaRBCS1B: LUC transgene. Sixteen luc(+) (firefly luciferase positive) T1 plants were isolated. Six of these were due to illegitimate recombination events resulting in a gene trapping effect. Nine resulted from homologous recombination between paralogous RBCSB sequences associated with T-DNA integration. The frequency of somatic homologous recombination associated with T-DNA integration was almost 200 times higher than previously reported rates of meiotic homologous recombination with the same genes. The distribution of (somatic homologous) recombination resolution sites generally fits a fractional interval length model. However, a small region adjacent to an indel showed a significant over-representation of resolution sites, suggesting that DNA mismatch recognition may also play an important role in the positioning of somatic resolution sites. The frequency of somatic resolution within exon-2 was significantly different from that previously observed during meiotic recombination.

  7. Evaluation of allele frequencies of inherited disease genes in subgroups of American Quarter Horses.

    Science.gov (United States)

    Tryon, Robert C; Penedo, M Cecilia T; McCue, Molly E; Valberg, Stephanie J; Mickelson, James R; Famula, Thomas R; Wagner, Michelle L; Jackson, Mark; Hamilton, Michael J; Nooteboom, Sabine; Bannasch, Danika L

    2009-01-01

    To estimate allele frequencies of the hyperkalaemic periodic paralysis (HYPP), lethal white foal syndrome (LWFS), glycogen branching enzyme deficiency (GBED), hereditary equine regional dermal asthenia (HERDA), and type 1 polysaccharide storage myopathy (PSSM) genes in elite performance subgroups of American Quarter Horses (AQHs). Prospective genetic survey. 651 elite performance AQHs, 200 control AQHs, and 180 control American Paint Horses (APHs). Elite performance AQHs successful in 7 competitive disciplines (barrel racing, cutting, halter, racing, reining, western pleasure, and working cow horse) were geno- typed for 5 disease-causing alleles. Age-matched control AQHs and APHs were used to establish comparative whole-breed estimates of allele frequencies. Highest allele frequencies among control AQHs were for type 1 PSSM (0.055) and GBED (0.054), whereas HERDA (0.021) and HYPP (0.008) were less prevalent. Control APHs uniquely harbored LWFS (0.107) and had high prevalence of HYPP (0.025), relative to AQHs. Halter horse subgroups had significantly greater allele frequencies for HYPP (0.299) and PSSM (0.155). Glycogen branching enzyme deficiency, HERDA, and PSSM were found broadly throughout subgroups; cutting subgroups were distinct for HERDA (0.142), and western pleasure subgroups were distinct for GBED (0.132). Racing and barrel racing subgroups had the lowest frequencies of the 5 disease genes. Accurate estimates of disease-causing alleles in AQHs and APHs may guide use of diagnostic genetic testing, aid management of genetic diseases, and help minimize production of affected foals.

  8. Differences in dinucleotide frequencies of thermophilic genes encoding water soluble and membrane proteins

    Institute of Scientific and Technical Information of China (English)

    Hiroshi NAKASHIMA; Yuka KURODA

    2011-01-01

    The occurrence frequencies of the dinucleotides of genes of three thermophilic and three mesophilic species from both archaea and eubacteria were investigated in this study. The genes encoding water soluble proteins were rich in the dinucleotides of purine dimers, whereas the genes encoding membrane proteins were rich in pyrimidine dimers. The dinucleotides of purine dimers are the counterparts of pyrimidine dimers in a double-stranded DNA. The purine/pyrimidine dimers were favored in the thermophiles but not in the mesophiles, based on comparisons of observed and expected frequencies. This finding is in agreement with our previous study which showed that purine/pyrimidine dimers are positive factors that increase the thermal stability of DNA. The dinucleotides AA, AG, and GA are components of the codons of charged residues of Glu, Asp, Lys, and Arg, and the dinucleotides TT, CT, and TC are components of the codons of hydrophobic residues of Leu, He, and Phe. This is consistent with the suitabilities of the different amino acid residues for water soluble and membrane proteins. Our analysis provides a picture of how thermophilic species produce water soluble and membrane proteins with distinctive characters: the genes encoding water soluble proteins use DNA sequences rich in purine dimers, and the genes encoding membrane proteins use DNA sequences rich in pyrimidine dimers on the opposite strand.

  9. Deletion of ku homologs increases gene targeting frequency in Streptomyces avermitilis.

    Science.gov (United States)

    Zhang, Xiaojuan; Chen, Wei; Zhang, Yang; Jiang, Libin; Chen, Zhi; Wen, Ying; Li, Jilun

    2012-06-01

    Streptomyces avermitilis is an industrially important soil bacterium known for production of avermectins, which are antiparasitic agents useful in animal health care, agriculture, and treatment of human infections. ku genes play a key role in the non-homologous end-joining pathway for repair of DNA double strand breaks. We identified homologs of eukaryotic ku70 and ku80 genes, termed ku1 and ku2, in S. avermitilis. Mutants with deletion of ku1, ku2, and both genes were constructed and their phenotypic changes were characterized. Deletion of ku genes had no apparent adverse effects on growth, spore formation, or avermectin production. The ku mutants, in comparison to wild-type strain, were slightly more sensitive to the DNA-damaging agent ethyl methanesulfonate, but not to UV exposure or to bleomycin. Gene targeting frequencies by homologous recombination were higher in the ku mutants than in wild-type strain. We conclude that ku-deleted strains will be useful hosts for efficient gene targeting and will facilitate functional analysis of genes in S. avermitilis and other industrially important bacterial strains.

  10. Cultural barriers associated with large gene frequency differences among Italian populations.

    Science.gov (United States)

    Barbujani, G; Vian, P; Fabbris, L

    1992-08-01

    Analysis of geographic variation for eight red cell markers in Italy shows significant spatial structure for most alleles. Effective population sizes estimated from FST values at these loci are much smaller than those predicted from data on consanguineous marriage, suggesting the presence of factors (presumably barriers) that have reduced gene flow and enhanced the evolutionary weight of genetic drift. Most regions of sharp gene frequency change correspond to geographic and linguistic barriers. Two allele frequencies are significantly correlated with measures of linguistic differentiation but not with indexes describing broad religious and social attitudes. The similarity between patterns of genetic and linguistic variation in Italy, also observed in a previous study, suggests that in specific areas linguistic diversity has acted as a biological barrier constraining mating, dispersal, or both. There is no evidence for a similar role of other extent cultural barriers.

  11. Pre-thymic somatic mutation leads to high mutant frequency at hypoxanthine-guanine phosphoribosyltransferase gene

    Energy Technology Data Exchange (ETDEWEB)

    Jett, J. [Lawrence Livermore National Lab., CA (United States)

    1994-12-01

    While characterizing the background mutation spectrum of the Hypoxathine-guanine phosphoribosyltransferase (HPRT) gene in a healthy population, an outlier with a high mutant frequency of thioguanine resistant lymphocytes was found. When studied at the age of 46, this individual had been smoking 60 cigarettes per day for 38 years. His mutant frequency was calculated at 3.6 and 4.2x10{sup {minus}4} for two sampling periods eight months apart. Sequencing analysis of the HPRT gene in his mutant thioguanine resistant T lymphocytes was done to find whether the cells had a high rate of mutation, or if the mutation was due to a single occurrence of mutation and, if so, when in the T lymphocyte development the mutation occurred. By T-cell receptor analysis it has been found that out of 35 thioguanine resistant clones there was no dominant gamma T cell receptor gene rearrangement. During my appointment in the Science & Engineering Research Semester, I found that 34 of those clones have the same base substitution of G{yields}T at cDNA position 197. Due to the consistent mutant frequency from both sampling periods and the varying T cell receptors, the high mutant frequency cannot be due to recent proliferation of a mature mutant T lymphocyte. From the TCR and DNA sequence analysis we conclude that the G{yields}T mutation must have occurred in a T lymphocyte precursor before thymic differentiation so that the thioguanine resistant clones share the same base substitution but not the same gamma T cell receptor gene.

  12. Reduced frequency of two activating KIR genes in patients with sepsis.

    Science.gov (United States)

    Oliveira, Luciana M; Portela, Pamela; Merzoni, Joice; Lindenau, Juliana D; Dias, Fernando S; Beppler, Jaqueline; Graebin, Pietra; Alho, Clarice S; Schwartsmann, Gilberto; Dal-Pizzol, Felipe; Jobim, Luiz Fernando; Jobim, Mariana; Roesler, Rafael

    2017-04-01

    Natural killer (NK) cell activity is regulated by activating and inhibitory signals transduced by killer cell immunoglobulin-like receptors (KIR). Diversity in KIR gene repertoire among individuals may affect disease outcome. Sepsis development and severity may be influenced by genetic factors affecting the immune response. Here, we examined sixteen KIR genes and their human leucocyte antigen (HLA) class I ligands in critical patients, aiming to identify patterns that could be associated with sepsis. Male and female patients (ages ranging between 14 and 94years-old) were included. DNA samples from 211 patients with sepsis and 60 controls (critical care patients with no sepsis) collected between 2004 and 2010 were included and genotyped for KIR genes using the polymerase chain reaction method with sequence-specific oligonucleotide (PCR-SSO), and for HLA genes using the polymerase chain reaction method with sequence-specific primers (PCR-SSP). The frequencies of activating KIR2DS1 and KIR3DS1 in sepsis patients when compared to controls were 41.23% versus 55.00% and 36.49% versus 51.67% (p=0.077 and 0.037 respectively before Bonferroni correction). These results indicate that activating KIR genes 2DS1 and 3DS1 may more prevalent in critical patients without sepsis than in patients with sepsis, suggesting a potential protective role of activating KIR genes in sepsis. Copyright © 2017 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  13. A Novel Approach of Low-frequency Ultrasonic Naked Plasmid Gene Delivery and Its Assessment

    Institute of Scientific and Technical Information of China (English)

    WEI WANG; ZHENG-ZHONG BIAN; YONG-JIE WU; YA-LIN MIAO

    2005-01-01

    Objective To deliver the naked genes into cells through the bioeffects of cell membrane porous produced by low-frequency ultrasound (US) and to investigate the safety by determining the threshold of cell damage and membrane permeability. Methods The suspension of red cells from chickens, rabbits, rats, and S180 cells was exposed to calibrated US field with different parameters in still and flowing state. Laser scanning confocal microscopy, fluorescent microscopy, scanning electron microscopy, flow cytometry and spectrophotometry were used to examine cell morphology, membrane permeability, enzymes, free radicals, naked gene expression efficiency, threshold of cell damage and cell viability. Results The plasmid of green fluorescent protein (GFP) as a reporter gene was delivered into S180 cells under optimal conditions without cell damage and cytotoxicity. The transfection rate was (35.83±2.53)% (n=6) in viable cells, and the cell viability was (90.17±1.47)% (n=6). Also, malondialdehyde, hydroxyl free radical, alkaline phosphatase, and acid phosphatase showed a S-shaped growth model (r=0.98±0.01) in response to the permeability change and alteration of cell morphology. The constant E of energy accumulation in US delivery at 90% cell viability was an optimal control factor, and at 80% cell viability was the damage threshold. Conclusion US under optimal conditions is a versatile gene therapy tool. The intensity of GFP expression in US group has a higher fluorescent peak than that in AVV-GFP group and control group (P<0.001). The optimal gene uptakes, expression of gene and safety depend on E, which can be applied to control gene delivery efficiency in combination with other parameters. The results are helpful for development of a novel clinical naked gene therapeutic system and non-hyperthermia cancer therapeutic system.

  14. The frequency distribution of vitamin D Receptor fok I gene polymorphism among Ugandan pulmonary TB patients

    Science.gov (United States)

    Acen, Ester L.; Worodria, William; Mulamba, Peter; Kambugu, Andrew; Erume, Joseph

    2016-01-01

    Background: Mycobacterium tuberculosis (TB) is still a major problem globally and especially in Africa. Vitamin D deficiency has been linked to TB in the past and studies have found vitamin D deficiency to be common among Ugandan TB patients. The functional activity of vitamin D is dependent on the genotype of the vitamin D receptor (VDR) polymorphic genes. Recent findings have indicated that VDR polymorphisms may cause increased resistance or susceptibility to TB. The vitamin D ligand and its receptor play a pivotal role in innate immunity by eliciting antimicrobial activity, which is important in prevention of TB. The fok I vitamin D receptor gene has extensively been examined in TB patients but findings so far have been inconclusive. Objectives: This study sought to investigate the frequency distribution of the VDR fok I gene polymorphisms in pulmonary TB patients and controls. Methods: A pilot case control study of 41 newly diagnosed TB patients and 41 healthy workers was set up. Vitamin D receptor fok I gene was genotyped. Results: The frequency distribution of fok I genotype in Ugandan TB patients was 87.8% homozygous-dominant (FF), 7.3% (Ff) heterozygous and 4.8% (ff) homozygous recessive. For normal healthy subjects the frequencies were (FF) 92.6%, (Ff) 2.4% and (ff) 4.8%. No significant difference was observed in the FF and ff genotypes among TB patients and controls. The Ff heterozygous genotype distribution appeared more in TB patients than in controls. A significant difference was observed in the fok I genotype among gender p value 0.02. No significant difference was observed in ethnicity, p value 0.30. Conclusions: The heterozygous Ff fok I genotype may be associated with TB in the Ugandan population.

  15. Digital PCR to assess gene-editing frequencies (GEF-dPCR) mediated by designer nucleases.

    Science.gov (United States)

    Mock, Ulrike; Hauber, Ilona; Fehse, Boris

    2016-03-01

    Genome editing using designer nucleases such as transcription activator-like effector nucleases (TALENs) or clustered regularly interspersed short palindromic repeats (CRISPR)-Cas9 nucleases is an emerging technology in basic and applied research. Whereas the application of editing tools, namely CRISPR-Cas9, has recently become very straightforward, quantification of resulting gene knockout rates still remains a bottleneck. This is particularly true if the product of a targeted gene is not easily detectable. To address this problem, we devised a novel gene-editing frequency digital PCR (GEF-dPCR) technique. GEF-dPCR exploits two differently labeled probes that are placed within one amplicon at the gene-editing target site to simultaneously detect wild-type and nonhomologous end-joining (NHEJ)-affected alleles. Taking advantage of the principle of dPCR, this enables concurrent quantification of edited and wild-type alleles in a given sample. We propose that our method is optimal for the monitoring of gene-edited cells in vivo, e.g., in clinical settings. Here we describe preparation, design of primers and probes, and setup and analysis of GEF-dPCR. The setup of GEF-dPCR requires up to 2 weeks (depending on the starting point); once the dPCR has been established, the protocol for sample analysis takes <1 d.

  16. Delta-sarcoglycan gene polymorphism frequency in Amerindian and Mestizo populations of Mexico.

    Science.gov (United States)

    Ordoñez-Razo, Rosa María; Canizales-Quinteros, Samuel; Rodríguez-Cruz, Maricela; Peñaloza, Rosenda; Minauro-Sanmiguel, Fernando; Canto-Cetina, Thelma; Canto, Patricia; Coral-Vázquez, Ramón; Salamanca-Gómez, Fabio

    2010-04-01

    Mutations on the delta-sarcoglycan gene have been associated with the development of both hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy. Recently, the polymorphism c.-94C>G was associated with HCM in Japanese patients. The aim of our study was to evaluate the frequency of c.-94C>G polymorphism in Mexican-Amerindian and Mexican-Mestizo populations. We analyzed the frequency of this polymorphism in 165 Mexican-Amerindian individuals (23 Triquis, 25 Zapotecos, 24 Mayas, 41 Nahuas, and 52 Mixtecos) and 100 unrelated Mexican-Mestizos. Allele frequencies were similar in all Amerindian groups (0.33 Triquis, 0.54 Zapotecos, 0.54 Mayas, 0.46 Nahuas, and 0.49 Mixtecos). When compared with Mexican-Mestizos, only Triquis were different (p = 0.00742). However, when comparing the total sample of the Amerindian population with the Mestizos, the difference was not significant (p = 0.12225). Allele frequencies of Mexican populations were higher than in Asians and less than African and European populations (p < 0.05). These data show that the distribution of the C allele is higher in Mexican populations studied and consequently it is necessary to define if this may be associated with genetic susceptibility for HCM in the Mexican patients.

  17. ABO and Rh (D group distribution and gene frequency; the first multicentric study in India

    Directory of Open Access Journals (Sweden)

    Amit Agrawal

    2014-01-01

    Full Text Available Background and Objectives: The study was undertaken with the objective to provide data on the ABO and Rh(D blood group distribution and gene frequency across India. Materials and Methods: A total of 10,000 healthy blood donors donating in blood banks situated in five different geographical regions of the country (North, South, East and Center were included in the study. ABO and Rh (D grouping was performed on all these samples. Data on the frequency of ABO and Rh(D blood groups was reported in simple numbers and percentages. Results: The study showed that O was the most common blood group (37.12% in the country closely followed by B at 32.26%, followed by A at 22.88% while AB was the least prevalent group at 7.74%. 94.61% of the donor population was Rh positive and the rest were Rh negative. Regional variations were observed in the distribution. Using the maximum likelihood method, the frequencies of the I A , I B and I O alleles were calculated and tested according to the Hardy Weinberg law of Equilibrium. The calculated gene frequencies are 0.1653 for I A (p, 0.2254 for I B (q and 0.6093 for I O (r. In Indian Population, O (r records the highest value followed by B (q and A (p; O > B > A. Conclusion: The study provides information about the relative distribution of various alleles in the Indian population both on a pan-India basis as well as region-wise. This vital information may be helpful in planning for future health challenges, particularly planning with regards to blood transfusion services.

  18. ABO and Rh (D) group distribution and gene frequency; the first multicentric study in India

    Science.gov (United States)

    Agrawal, Amit; Tiwari, Aseem Kumar; Mehta, Nidhi; Bhattacharya, Prasun; Wankhede, Ravi; Tulsiani, Sunita; Kamath, Susheela

    2014-01-01

    Background and Objectives: The study was undertaken with the objective to provide data on the ABO and Rh(D) blood group distribution and gene frequency across India. Materials and Methods: A total of 10,000 healthy blood donors donating in blood banks situated in five different geographical regions of the country (North, South, East and Center) were included in the study. ABO and Rh (D) grouping was performed on all these samples. Data on the frequency of ABO and Rh(D) blood groups was reported in simple numbers and percentages. Results: The study showed that O was the most common blood group (37.12%) in the country closely followed by B at 32.26%, followed by A at 22.88% while AB was the least prevalent group at 7.74%. 94.61% of the donor population was Rh positive and the rest were Rh negative. Regional variations were observed in the distribution. Using the maximum likelihood method, the frequencies of the IA, IB and IO alleles were calculated and tested according to the Hardy Weinberg law of Equilibrium. The calculated gene frequencies are 0.1653 for IA (p), 0.2254 for IB (q) and 0.6093 for IO (r). In Indian Population, O (r) records the highest value followed by B (q) and A (p); O > B > A. Conclusion: The study provides information about the relative distribution of various alleles in the Indian population both on a pan-India basis as well as region-wise. This vital information may be helpful in planning for future health challenges, particularly planning with regards to blood transfusion services. PMID:25161353

  19. Genetic relationships among native americans based on beta-globin gene cluster haplotype frequencies

    Directory of Open Access Journals (Sweden)

    Rita de Cassia Mousinho-Ribeiro

    2003-01-01

    Full Text Available The distribution of b-globin gene haplotypes was studied in 209 Amerindians from eight tribes of the Brazilian Amazon: Asurini from Xingú, Awá-Guajá, Parakanã, Urubú-Kaapór, Zoé, Kayapó (Xikrin from the Bacajá village, Katuena, and Tiriyó. Nine different haplotypes were found, two of which (n. 11 and 13 had not been previously identified in Brazilian indigenous populations. Haplotype 2 (+ - - - - was the most common in all groups studied, with frequencies varying from 70% to 100%, followed by haplotype 6 (- + + - +, with frequencies between 7% and 18%. The frequency distribution of the b-globin gene haplotypes in the eighteen Brazilian Amerindian populations studied to date is characterized by a reduced number of haplotypes (average of 3.5 and low levels of heterozygosity and intrapopulational differentiation, with a single clearly predominant haplotype in most tribes (haplotype 2. The Parakanã, Urubú-Kaapór, Tiriyó and Xavante tribes constitute exceptions, presenting at least four haplotypes with relatively high frequencies. The closest genetic relationships were observed between the Brazilian and the Colombian Amerindians (Wayuu, Kamsa and Inga, and, to a lesser extent, with the Huichol of Mexico. North-American Amerindians are more differentiated and clearly separated from all other tribes, except the Xavante, from Brazil, and the Mapuche, from Argentina. A restricted pool of ancestral haplotypes may explain the low diversity observed among most present-day Brazilian and Colombian Amerindian groups, while interethnic admixture could be the most important factor to explain the high number of haplotypes and high levels of diversity observed in some South-American and most North-American tribes.

  20. Evaluation of multidrug resistance-1 gene C>T polymorphism frequency in patients with asthma

    Directory of Open Access Journals (Sweden)

    Ümran Toru

    2015-10-01

    Full Text Available OBJECTIVES:Asthma is a chronic inflammatory lung disease characterized by bronchial hyperresponsiveness and airflow obstruction. Genetic and oxidative stress factors, in addition to pulmonary and systemic inflammatory processes, play a pivotal role in the pathogenesis of asthma. The products of the multidrug resistance-1 gene protect lung tissue from oxidative stress. Here, we aimed to evaluate the association between the multidrug resistance-1 gene C>T polymorphism and asthma with regard to oxidative stress-related parameters of asthmatic patients.METHODS:Forty-five patients with asthma and 27 healthy age-matched controls were included in this study. Blood samples were collected in tubes with ethylenediaminetetraacetic acid. DNA was extracted from the blood samples. The multidrug resistance-1 gene polymorphism was detected by polymerase chain reaction and a subsequent enzyme digestion technique. The serum levels of total oxidant status and total antioxidant status were determined by the colorimetric measurement method.RESULTS:The heterozygous polymorphic genotype was the most frequent in both groups. A significant difference in the multidrug resistance-1 genotype frequencies between groups indicated an association of asthma with the TT genotype. A significant difference between groups was found for wild type homozygous participants and carriers of polymorphic allele participants. The frequency of the T allele was significantly higher in asthmatic patients. The increase in the oxidative stress index parameter was significant in the asthma group compared with the control group.CONCLUSIONS:The multidrug resistance-1 gene C/T polymorphism may be an underlying genetic risk factor for the development of asthma via oxidant-antioxidant imbalance, leading to increased oxidative stress.

  1. Frequency of p53 gene mutation and protein expression in oral squamous cell carcinoma.

    Science.gov (United States)

    Ara, Nighat; Atique, Muhammad; Ahmed, Sohaib; Ali Bukhari, Syed Gulzar

    2014-10-01

    To determine the frequency of p53 gene mutation and protein expression in Oral Squamous Cell Carcinoma (OSCC) and to establish correlation between the two. Analytical study. Histopathology Department and Molecular Biology Laboratory, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from May 2010 to May 2011. Thirty diagnosed cases of OSCC were selected by consecutive sampling. Seventeen were retrieved from the record files of the AFIP, and 13 fresh/frozen sections were selected from patients reporting to the Oral Surgery Department, Armed Forces Institute of Dentistry (AFID). Gene p53 mutation was analyzed in all the cases using PCRSSCP analysis. DNA was extracted from the formalin-fixed and paraffin-embedded tissue sections and fresh/frozen sections. DNA thus extracted was amplified by polymerase chain reaction. The amplified products were denatured and finally analyzed by gel electrophoresis. Gene mutation was detected as electrophoretic mobility shift. The immunohistochemical marker p53 was applied to the same 30 cases and overexpression of protein p53 was recorded. Immunohistochemical expression of marker p53 was positive in 67% [95% Confidence Interval (CI) 48.7-80.9] of the cases. Mutations of the p53 gene were detected in 23% (95% CI 11.5-41.2) of the OSCC. No statistically significant correlation was found between p53 gene mutation and protein p53 expression (rs=-0.057, p=0.765). A substantial number of patients have p53 gene mutation (23%) and protein p53 expression (67%) in oral squamous cell carcinoma (OSCC).

  2. Frequency modulation of stochastic gene expression bursts by strongly interacting small RNAs

    Science.gov (United States)

    Kumar, Niraj; Jia, Tao; Zarringhalam, Kourosh; Kulkarni, Rahul V.

    2016-10-01

    The sporadic nature of gene expression at the single-cell level—long periods of inactivity punctuated by bursts of mRNA or protein production—plays a critical role in diverse cellular processes. To elucidate the cellular role of bursting in gene expression, synthetic biology approaches have been used to design simple genetic circuits with bursty mRNA or protein production. Understanding how such genetic circuits can be designed with the ability to control burst-related parameters requires the development of quantitative stochastic models of gene expression. In this work, we analyze stochastic models for the regulation of gene expression bursts by strongly interacting small RNAs. For the parameter range considered, results based on mean-field approaches are significantly inaccurate and alternative analytical approaches are needed. Using simplifying approximations, we obtain analytical results for the corresponding steady-state distributions that are in agreement with results from stochastic simulations. These results indicate that regulation by small RNAs, in the strong interaction limit, can be used to effectively modulate the frequency of bursting. We explore the consequences of such regulation for simple genetic circuits involving feedback effects and switching between promoter states.

  3. Frequency modulation of stochastic gene expression bursts by strongly interacting small RNAs.

    Science.gov (United States)

    Kumar, Niraj; Jia, Tao; Zarringhalam, Kourosh; Kulkarni, Rahul V

    2016-10-01

    The sporadic nature of gene expression at the single-cell level-long periods of inactivity punctuated by bursts of mRNA or protein production-plays a critical role in diverse cellular processes. To elucidate the cellular role of bursting in gene expression, synthetic biology approaches have been used to design simple genetic circuits with bursty mRNA or protein production. Understanding how such genetic circuits can be designed with the ability to control burst-related parameters requires the development of quantitative stochastic models of gene expression. In this work, we analyze stochastic models for the regulation of gene expression bursts by strongly interacting small RNAs. For the parameter range considered, results based on mean-field approaches are significantly inaccurate and alternative analytical approaches are needed. Using simplifying approximations, we obtain analytical results for the corresponding steady-state distributions that are in agreement with results from stochastic simulations. These results indicate that regulation by small RNAs, in the strong interaction limit, can be used to effectively modulate the frequency of bursting. We explore the consequences of such regulation for simple genetic circuits involving feedback effects and switching between promoter states.

  4. Observed and predicted changes in virulence gene frequencies at 11 loci in a local barley powdery mildew population

    DEFF Research Database (Denmark)

    Hovmøller, M.S.; Munk, L.; Østergård, H.

    1993-01-01

    a survey comprising 11 virulence loc. Predictions were based on a model where selection forces were estimated through detailed mapping in the local area of host cultivars and their resistance genes, and taking into account the changes in distribution of host cultivars during the year caused by growth......The aim of the present study was to investigate observed and predicted changes in virulence gene frequencies in a local aerial powdery mildew population subject to selection by different host cultivars in a local barley area. Observed changes were based on genotypic frequencies obtained through...... with a constant distribution of host cultivars. Significant changes in gene frequencies were observed for virulence genes subject to strong direct selection as well as for genes subject mainly to indirect selection (hitchhiking). These patterns of changes were generally as predicted from the model. The influence...

  5. Model-based calculating tool for pollen-mediated gene flow frequencies in plants.

    Science.gov (United States)

    Lei, Wang; Bao-Rong, Lu

    2016-12-30

    The potential social-economic and environmental impacts caused by transgene flow from genetically engineered (GE) crops have stimulated worldwide biosafety concerns. To determine transgene flow frequencies resulted from pollination is the first critical step for assessing such impacts, in addition to the determination of transgene expression and fitness in crop-wild hybrid descendants. Two methods are commonly used to estimate pollen-mediated gene flow (PMGF) frequencies: field experimenting and mathematical modeling. Field experiments can provide relatively accurate results but are time/resource consuming. Modeling offers an effective complement for PMGF experimental assessment. However, many published models describe PMGF by mathematical equations and are practically not easy to use. To increase the application of PMGF modeling for the estimation of transgene flow, we established a tool to calculate PMGF frequencies based on a quasi-mechanistic PMGF model for wind-pollination species. This tool includes a calculating program displayed by an easy-operating interface. PMGF frequencies of different plant species can be quickly calculated under different environmental conditions by including a number of biological and wind speed parameters that can be measured in the fields/laboratories or obtained from published data. The tool is freely available in the public domain (http://ecology.fudan.edu.cn/userfiles/cn/files/Tool_Manual.zip). Case studies including rice, wheat, and maize demonstrated similar results between the calculated frequencies based on this tool and those from published PMGF data. This PMGF calculating tool will provide useful information for assessing and monitoring social-economic and environmental impacts caused by transgene flow from GE crops. This tool can also be applied to determine the isolation distances between GE and non-GE crops in a coexistence agro-ecosystem, and to ensure the purity of certified seeds by setting proper isolation distances

  6. Covariation of gene frequencies in a stepping-stone lattice of populations1

    Science.gov (United States)

    Felsenstein, Joseph

    2015-01-01

    For a one- or two-dimensional lattice of finite length consisting of populations, each of which has the same population size, the classical stepping-stone model has been used to approximate the patterns of variation at neutral loci in geographic regions. In the pioneering papers by Maruyama (1970a, 1970b, 1971) the changes of gene frequency at a locus subject to neutral mutation between two alleles, migration, and random genetic drift were modeled by a vector autoregression model. Maruyama was able to use the spectrum of the migration matrix, but to do this he had to introduce approximations in which there was either extra mutation in the terminal populations, or extra migration from the subterminal population into the terminal population. In this paper a similar vector autoregression model is used, but it proves possible to obtain the eigenvalues and eigenvectors of the migration matrix without those approximations. Approximate formulas for the variances and covariances of gene frequencies in different populations are obtained, and checked by numerical iteration of the exact covariances of the vector autoregression model. PMID:25542067

  7. High frequency of the D allele of the angiotensin-converting enzyme gene in Arabic populations

    Directory of Open Access Journals (Sweden)

    Salem Abdel

    2009-06-01

    Full Text Available Abstract Background The angiotensin-converting enzyme (ACE gene in humans has an insertion-deletion (I/D polymorphic state in intron 16 on chromosome 17q23. This polymorphism has been widely investigated in different populations due to its association with the renin-angiotensin system. However, similar studies for Arab populations are limited. This study addresses the distribution of the ACE gene polymorphism in three Arab populations (Egyptians, Jordanians and Syrians. Findings The polymorphisms of ACE gene were investigated using polymerase chain reaction for detection of an I/D mutation. The results showed a high frequency of the ACE D allele among the three Arab populations, Egyptians (0.67, Jordanians (0.66 and Syrians (0.60, which is similar to those obtained from previous studies for Arab populations. Conclusion The relationship between ACE alleles and disease in these three Arab populations is still not known, but the present results clearly suggest that geographic origin should be carefully considered in the increasing number of studies on the association between ACE alleles and disease etiology. This study adds to the data showing the wide variation in the distribution of the ACE alleles in different populations and highlights that great care needs to be taken when interpreting clinical data on the association of the ACE alleles with different diseases.

  8. Analysis of KIR gene frequencies and HLA class I genotypes in breast cancer and control group.

    Science.gov (United States)

    Jobim, Maria Regina; Jobim, Mariana; Salim, Patrícia H; Portela, Pâmela; Jobim, Luiz Fernando; Leistner-Segal, Sandra; Bittelbrunn, Ana Cristina; Menke, Carlos Henrique; Biazús, Jorge Villanova; Roesler, Rafael; Schwartsmann, Gilberto

    2013-09-01

    Breast cancer is the main cause of cancer-related death among women, with a 0.5% increase in incidence per year. Natural killer cells (NK) are part of the innate immune system recognizing class I HLA molecules on target cells through their membrane receptors, called killer cell immunoglobulin-like receptors (KIR). The aim of our study was to evaluate the association between the KIR genes and HLA alleles in patients with breast cancer and healthy controls. Two hundred thirty patients with breast cancer and 272 healthy controls were typed for HLA class I and KIR genes by PCR-SSO. When both groups were compared, the presence of inhibitory KIR2DL2 receptors was significantly higher in breast cancer patients than in healthy controls. No significant differences were found for HLA-C2 and HLA-Bw4. However, a higher frequency of HLA-C1 in breast cancer patients was observed. These findings suggest a potential role for the KIR gene system in breast cancer. Further studies to confirm this observation are warranted.

  9. Analysis of KIR gene frequencies and HLA class I genotypes in prostate cancer and control group.

    Science.gov (United States)

    Portela, P; Jobim, L F; Salim, P H; Koff, W J; Wilson, T J; Jobim, M R; Schwartsmann, G; Roesler, R; Jobim, M

    2012-10-01

    Prostate cancer is the second most common cancer in men, with a significant increase in incidence and mortality in men over 50 years of age. Natural killer cells (NK) are part of the innate immune system recognizing class I HLA molecules on target cells through their membrane receptors, called killer cell immunoglobulin-like receptors (KIR). The aim of our study is to evaluate the association between the KIR genes and HLA alleles in patients with prostate cancer and healthy controls. Two hundred patients with prostate cancer and 185 healthy controls were typed for HLA class I and KIR genes by PCR-SSP. When both groups were compared, no significant differences were found for HLA-C group 1 and group 2, HLA-Bw4, HLA-A3 and A11. No difference was seen either in KIR frequency between patients with prostate cancer and controls. In conclusion, our data suggest no potential role for the KIR gene system in prostate cancer.

  10. High frequency of TARDBP gene mutations in Italian patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Corrado, Lucia; Ratti, A; Gellera, C; Buratti, E; Castellotti, B; Carlomagno, Y; Ticozzi, N; Mazzini, L; Testa, L; Taroni, F; Baralle, F E; Silani, V; D'Alfonso, S

    2009-04-01

    Recent studies identified rare missense mutations in amyotrophic lateral sclerosis (ALS) patients in the TARDBP gene encoding TAR DNA binding protein (TDP)-43, the major protein of the ubiquitinated inclusions (UBIs) found in affected motor neurons (MNs). The aim of this study was to further define the spectrum of TARDBP mutations in a large cohort of 666 Italian ALS patients (125 familial and 541 sporadic cases). The entire coding region was sequenced in 281 patients, while in the remaining 385 cases only exon 6 was sequenced. In 18 patients, of which six are familial, we identified 12 different heterozygous missense mutations (nine novel) all locating to exon 6, which were absent in 771 matched controls. The c.1144G>A (p.A382T) variation was observed in seven patients, thus representing the most frequent TARDBP mutation in ALS. Analysis of microsatellites surrounding the TARDBP gene indicated that p.A382T was inherited from a common ancestor in 5 of the 7 patients. Altogether, the frequency of TARDBP gene mutations appears to be particularly high in Italian ALS patients compared to individuals of mainly Northern European origin (2.7% vs. 1%). Western blot analysis of lymphocyte extracts from two patients carrying the p.A382T and p.S393L TARDBP mutations showed the presence of lower molecular weight TDP-43 bands, which were more abundant than observed in healthy controls and patients negative for TARDBP mutations. In conclusion, this report contributes to the demonstration of the causative role of the TARDBP gene in ALS pathogenesis and indicates that mutations may affect the stability of the protein even in nonneuronal tissues. (c) 2009 Wiley-Liss, Inc.

  11. Bards, poets, and cliques: frequency-dependent selection and the evolution of language genes.

    Science.gov (United States)

    Cartwright, Reed A

    2011-09-01

    The ability of humans to communicate via language is a complex, adapted phenotype, which undoubtedly has a recently evolved genetic component. However, the evolutionary dynamics of language-associated alleles are poorly understood. To improve our knowledge of such systems, a population-genetics model for language-associated genes is developed. (The model is general and applicable to social interactions other than communication.) When an allele arises that potentially improves the ability of individuals to communicate, it will experience positive frequency-dependent selection because its fitness will depend on how many other individuals communicate the same way. Consequently, new and rare alleles are selected against, posing a problem for the evolutionary origin of language. However, the model shows that if individuals form language-based cliques, then novel language-associated alleles can sweep through a population. Thus, the origin of language ability can be sufficiently explained by Darwinian processes operating on genetic diversity in a finite population of human ancestors.

  12. Increased conjugation frequencies in clinical Enterococcus faecium strains harbouring the enterococcal surface protein gene esp.

    Science.gov (United States)

    Lund, B; Billström, H; Edlund, C

    2006-06-01

    This study compared the in-vitro ability of Enterococcus faecium isolates of different origin to acquire vanA by conjugation in relation to the occurrence of the esp gene. In total, 29 clinical isolates (15/29 esp+), 30 normal intestinal microflora isolates (2/30 esp+) and one probiotic strain (esp-) were studied with a filter-mating assay. Conjugation events were confirmed by PCR and pulsed-field gel electrophoresis. Among the infection-derived isolates, the esp+ isolates had higher conjugation frequencies compared with esp- isolates (p < 0.001), with a median value of 6.4 x 10(-6) transconjugants/donor. The probiotic strain was shown to acquire vanA vancomycin resistance in in-vitro filter mating experiments.

  13. Genetic distances between Chinese populations calculated on gene frequencies of 38 loci

    Institute of Scientific and Technical Information of China (English)

    杜若甫; 肖春杰; L. L. Cavalli-Sforza

    1997-01-01

    Genetic distances were calculated for Han subpopulations in different provinces, cities and au-tonomous regions and ethnic minorities in China by using gene frequency data of 38 loci, and genetic trees were con-structed. The results showed that, among both Han and ethnic minorities, there were two types, i.e. southern and northern Mongoloids, with Yangtze River as boundary. Therefore, both African origin theory and local origin theory about the modern man should answer the question; when did these two types separate and how did they develop. This paper also conclusively proved genetically that the Han subpopulations in different regions are genetically close to the lo-cal ethnic minorities, which indicates that much blood of ethnic minorities has mixed into Han, at the same time, some blood of Han also has mixed into the local ethnic minorities.

  14. High-frequency conjugative transfer of antibiotic resistance genes to Yersinia pestis in the flea midgut.

    Science.gov (United States)

    Hinnebusch, B Joseph; Rosso, Marie-Laure; Schwan, Tom G; Carniel, Elisabeth

    2002-10-01

    The acquisition of foreign DNA by horizontal transfer from unrelated organisms is a major source of variation leading to new strains of bacterial pathogens. The extent to which this occurs varies widely, due in part to lifestyle factors that determine exposure to potential donors. Yersinia pestis, the plague bacillus, infects normally sterile sites in its mammalian host, but forms dense aggregates in the non-sterile digestive tract of its flea vector to produce a transmissible infection. Here we show that unrelated co-infecting bacteria in the flea midgut are readily incorporated into these aggregates, and that this close physical contact leads to high-frequency conjugative genetic exchange. Transfer of an antibiotic resistance plasmid from an Escherichia coli donor to Y. pestis occurred in the flea midgut at a frequency of 10-3 after only 3 days of co-infection, and after 4 weeks 95% of co-infected fleas contained an average of 103 antibiotic-resistant Y. pestis transconjugants. Thus, transit in its arthropod vector exposes Y. pestis to favourable conditions for efficient genetic exchange with microbial flora of the flea gut. Horizontal gene transfer in the flea may be the source of antibiotic-resistant Y. pestis strains recently isolated from plague patients in Madagascar.

  15. Frequencies of VNTR and RFLP polymorphisms associated with factor VIII gene in Singapore

    Energy Technology Data Exchange (ETDEWEB)

    Fong, I.; Lai, P.S.; Ouah, T.C. [National Univ. of Singapore (Malaysia)] [and others

    1994-09-01

    The allelic frequency of any polymorphism within a population determines its usefulness for genetic counselling. This is important in populations of non-Caucasian origin as RFLPs may significantly differ among ethnic groups. We report a study of five intragenic polymorphisms in factor VIII gene carried out in Singapore. The three PCR-based RFLP markers studied were Intron 18/Bcl I, Intron 19/Hind III and Intron 22/Xba I. In an analysis of 148 unrelated normal X chromosomes, the allele frequencies were found to be A1 = 0.18, A2 = 0.82 (Bcl I RFLP), A1 = 0.80, A2 = 0.20 (Hind III RFLP) and A1 = 0.58, and A2 = 0.42 (Xba I RFLP). The heterozygosity rates of 74 females analyzed separately were 31%, 32% and 84.2%, respectively. Linkage disequilibrium was also observed to some degree between Bcl I and Hind III polymorphism in our population. We have also analyzed a sequence polymorphism in Intron 7 using hybridization with radioactive-labelled {sup 32}P allele-specific oligonucleotide probes. This polymorphism was not very polymorphic in our population with only 2% of 117 individuals analyzed being informative. However, the use of a hypervariable dinucleotide repeat sequence (VNTR) in Intron 13 showed that 25 of our of 27 (93%) females were heterozygous. Allele frequencies ranged from 1 to 55 %. We conclude that a viable strategy for molecular analysis of Hemophilia A families in our population should include the use of Intron 18/Bcl I and Intron 22/Xba I RFLP markers and the Intron 13 VNTR marker.

  16. THE VALIDATION OF THE RESULTS OF MICROARRAY STUDIES OF ASSOCIATION BETWEEN GENE POLYMORPHISMS AND THE FREQUENCY OF RADIATION EXPOSURE MARKERS

    Directory of Open Access Journals (Sweden)

    M. V. Khalyuzova

    2014-01-01

    Full Text Available The results from the selective validation research into the association between genetic polymorphisms and the frequency of cytogenetic abnormalities on a large independent sample are analyzed. These polymorphisms have been identified previously during own microarray studies. It has been shown an association with the frequency of dicentric and ring chromosomes induced by radiation exposure. The study was conducted among Siberian Group of Chemical Enterprises healthy employees (n = 573 exposed to professional irradiation in a dose range of 40–400 mSv. We have found that 5 SNP are confirmed to be associated with the frequency of dicentric and ring: INSR rs1051690 – insulin receptor gene; WRNrs2725349 – Werner syndrome gene, RecQ helicase-like; VCAM1 rs1041163 – vascular cell adhesion molecule 1 gene; PCTP rs2114443 – phosphatidylcholine transfer protein gene; TNKS rs7462102 – tankyrase gene; TRF1-interacting ankyrin-related ADP-ribose polymerase. IGF1 rs2373721 – insulin-like growth factor 1 gene has not confirmed to be associated with the frequency of dicentric and ring chromosomes.

  17. Low frequency of ESRRA-C11orf20 fusion gene in ovarian carcinomas.

    Science.gov (United States)

    Micci, Francesca; Panagopoulos, Ioannis; Thorsen, Jim; Davidson, Ben; Tropé, Claes Gøran; Heim, Sverre

    2014-02-01

    The identification of recurrent gene fusions in common epithelial cancers--for example, TMPRSS2/ERG in prostate cancer and EML4/ALK in nonsmall cell lung carcinomas--has raised the question of whether fusion genes are pathogenetically important also in ovarian carcinomas. The first recurrent fusion transcript in serous ovarian carcinomas was reported by Salzman et al. in 2011, who used deep paired-end sequencing to detect the fusion gene ESRRA-C11orf20 in 10 out of 67 (15%) serous ovarian carcinomas examined, a finding that holds great promise for our understanding of ovarian tumorigenesis as well as, potentially, for new treatment strategies. We wanted to test how frequent the ESRRA/C11orf20 fusion is in ovarian carcinomas of all subtypes, and therefore examined a series of 230 ovarian carcinomas of which 197 were of the serous subtype and 163 of the 197 were of stages III and IV--that is, the very same carcinoma subset where the fusion transcript had been found. We performed PCR and high-throughput sequencing analyses in search of the fusion transcript. We used the same primers described previously for the detection of the fusion and the same primer combination, but found no ESRRA/C11orf20 fusion in our series. A synthetic DNA plasmid containing the reported ESRRA/C11orf20 fusion was included as a positive control for our PCR experiments. Data from high-throughput sequencing of 23 ovarian carcinomas were screened in search of alternative partner(s) for the ESRRA and/or C11orf20 gene, but none was found. We conclude that the frequency of the ESRRA/C11orf20 gene fusion in serous ovarian carcinomas of stages III and IV must be considerable less than that reported previously (0/163 in our experience compared with 10/67 in the previous study). At the very least, it seems clear that the said fusion cannot be a common pathogenetic event in this tumor type.

  18. Low frequency of ESRRA-C11orf20 fusion gene in ovarian carcinomas.

    Directory of Open Access Journals (Sweden)

    Francesca Micci

    2014-02-01

    Full Text Available The identification of recurrent gene fusions in common epithelial cancers--for example, TMPRSS2/ERG in prostate cancer and EML4/ALK in nonsmall cell lung carcinomas--has raised the question of whether fusion genes are pathogenetically important also in ovarian carcinomas. The first recurrent fusion transcript in serous ovarian carcinomas was reported by Salzman et al. in 2011, who used deep paired-end sequencing to detect the fusion gene ESRRA-C11orf20 in 10 out of 67 (15% serous ovarian carcinomas examined, a finding that holds great promise for our understanding of ovarian tumorigenesis as well as, potentially, for new treatment strategies. We wanted to test how frequent the ESRRA/C11orf20 fusion is in ovarian carcinomas of all subtypes, and therefore examined a series of 230 ovarian carcinomas of which 197 were of the serous subtype and 163 of the 197 were of stages III and IV--that is, the very same carcinoma subset where the fusion transcript had been found. We performed PCR and high-throughput sequencing analyses in search of the fusion transcript. We used the same primers described previously for the detection of the fusion and the same primer combination, but found no ESRRA/C11orf20 fusion in our series. A synthetic DNA plasmid containing the reported ESRRA/C11orf20 fusion was included as a positive control for our PCR experiments. Data from high-throughput sequencing of 23 ovarian carcinomas were screened in search of alternative partner(s for the ESRRA and/or C11orf20 gene, but none was found. We conclude that the frequency of the ESRRA/C11orf20 gene fusion in serous ovarian carcinomas of stages III and IV must be considerable less than that reported previously (0/163 in our experience compared with 10/67 in the previous study. At the very least, it seems clear that the said fusion cannot be a common pathogenetic event in this tumor type.

  19. Total beta-globin gene deletion has high frequency in Filipinos

    Energy Technology Data Exchange (ETDEWEB)

    Patrick, N.; Miyakawa, F.; Hunt, J.A. [Univ. of Hawaii, Honolulu, HI (United States)] [and others

    1994-09-01

    The distribution of {beta}-thalassemia [{beta}{sup Th}] mutations is unique to each ethnic group. Most mutations affect one or a few bases; large deletions have been rare. Among families screened in Hawaii, [{beta}{sup Th}] heterozygotes were diagnosed by microcytosis, absence of abnormal hemoglobins on isoelectric focusing, and raised Hb A{sub 2} by chromatography. Gene frequency for {beta}{sup Th} was 0.02 in Filipinos. In Filipinos, polymerase chain reaction [PCR] with denaturing gradient gel electrophoresis for {beta}{sup Th} mutations detected a mutation in only 6 of 42 {beta}{sup Th} heterozygotes; an IVS2-666 C/T polymorphism showed non-heterozygosity in 37 and heterozygosity in only 5 of these {beta}{sup Th} heterozygotes. One {beta}{sup Th}/{beta}{sup Th} major patient and his mother had no mutation detected by allele-specific oligomer hybridization; PCR failed to amplify any DNA from his {beta}-globin gene. After a total {beta}-globin gene deletion [{beta}{sup Del}] was found in a Filipino family in Ontario, specific PCR amplification for {beta}{sup Del} detected this in 43 of 53 {beta}{sup Th} Filipino samples tested; the above {beta}{sup Th}/{beta}{sup Th} patient was a ({beta}{sup Del}/{beta}{sup Del}) homozygote. The {beta}{sup Del} may account for over 60% of all {beta}{sup Th} alleles in Filipinos; this is the highest proportion of a deletion {beta}{sup Th} mutation reported from any population. Most but not all {beta}{sup Del} heterozygotes had high Hb F [5.13 {plus_minus} 3.94 mean {plus_minus} 1 s.d.] compared to the codon 41/42 four base deletion common in Chinese [2.30 {plus_minus} 0.86], or to {beta}{sup Th} heterozygotes with normal {alpha}-globin genes [2.23 {plus_minus} 0.80].

  20. [Gene frequencies and heterozygosity of the population of Donetsk Province, Ukraine by the alleles of the ABO and Rhesus systems].

    Science.gov (United States)

    Mukhin, V N

    1999-01-01

    Frequency and heterozygosity indices of AB0 and Rh gene systems in the population of Donetsk Province were calculated. Uneven distribution of the genes was found and heterozygosity indices of the population were 0.554-0.573 for AB0 and 0.410-0.499 for Rh. Heterozygosity in this population was higher than average heterozygosity in total population of Ukraine as a result of intensive migrations and prevalence of heterolocal marriages over homolocal ones.

  1. Multi-frequency survey of background radiations of the Universe. The "Cosmological Gene" project. First results

    Science.gov (United States)

    Parijskij, Yu. N.; Mingaliev, M. G.; Nizhel'Skii, N. A.; Bursov, N. N.; Berlin, A. B.; Grechkin, A. A.; Zharov, V. I.; Zhekanis, G. V.; Majorova, E. K.; Semenova, T. A.; Stolyarov, V. A.; Tsybulev, P. G.; Kratov, D. V.; Udovitskii, R. Yu.; Khaikin, V. B.

    2011-10-01

    The results of the first stage of the "Cosmological Gene" project of the Russian Academy of Sciences are reported. These results consist in the accumulation of multi-frequency data in 31 frequency channels in the wavelength interval 1-55 cm with maximum achievable statistical sensitivity limited by the noise of background radio sources at all wavelengths exceeding 1.38 cm. The survey region is determined by constraints 00 h microwave background are reported as well as the contribution of these noise components in millimeter-wave experiments to be performed in the nearest years. The role of dipole radio emission of fullerene-type dust nanostructures is shown to be small. The most precise estimates of the role of background radio sources with inverted spectra are given and these sources are shown to create no serious interference in experiments. The average spectral indices of the weakest sources of the NVSS and FIRST catalogs are estimated. The "saturation" data for all wavelengths allowed a constraint to be imposed on the Sunyaev-Zeldovich noise (the SZ noise) at all wavelengths, and made it possible to obtain independent estimates of the average sky temperature from sources, substantially weaker than those listed in the NVSS catalog. These estimates are inconsistent with the existence of powerful extragalactic synchrotron background associated with radio sources. Appreciable "quadrupole" anisotropy in is detected in the distribution of the spectral index of the synchrotron radiation of the Galaxy, and this anisotropy should be taken into account when estimating the polarization of the cosmic microwave background on small l. All the results are compared to the results obtained by foreign researchers in recent years.

  2. Effect of low frequency (LF) electric fields on gene expression of a bone human cell line.

    Science.gov (United States)

    Caputo, Mariella; Zirpoli, Hylde; De Rosa, Maria Caterina; Rescigno, Tania; Chiadini, Francesco; Scaglione, Antonio; Stellato, Claudia; Giurato, Giorgio; Weisz, Alessandro; Tecce, Mario Felice; Bisceglia, Bruno

    2014-12-01

    We evaluated the effects, on cultured human SaOS-2 cells, of exposures to the low frequency (LF) electric signal (60 kHz sinusoidal wave, 24.5 V peak-to-peak voltage, amplitude modulated by a 12.5 Hz square wave, 50% duty cycle) from an apparatus of current clinical use in bone diseases requiring regenerating processes. Cells in flasks were exposed to a capacitively coupled electric field giving electric current density in the sample of 4 µA/cm(2). The whole expressed cellular mRNAs were systematically analyzed by "DNA microchips" technology to identify all individual species quantitatively affected by field exposure. Comparisons were made between RNA samples from exposed and control sham-exposed cells. Results indicated that immediately and 4 h after exposure there were almost no differentially modulated mRNA species. However, samples obtained at 24 h after exposure showed a small number of limitedly differential signals (7 down-regulated and 3 up-regulated with a cut-off value of ±1.5; 38 and 11, respectively, with a cut-off value of ±1.3), which included mostly mRNA encoding transcription factors and DNA binding proteins. Nevertheless, in identical experimental conditions, we previously demonstrated enzymatic changes of alkaline phosphatase occurring immediately after exposure and declining in a few hours. Therefore, since enzymatic changes occur before those observed at gene regulation level, it is conceivable that only earlier effects are directly due the treatment and then these effects are later able to affect gene expression only indirectly.

  3. Genotypic and allelic frequencies of gene polymorphisms associated with meat tenderness in Nellore beef cattle.

    Science.gov (United States)

    Carvalho, M E; Eler, J P; Bonin, M N; Rezende, F M; Biase, F H; Meirelles, F V; Regitano, L C A; Coutinho, L L; Balieiro, J C C; Ferraz, J B S

    2017-02-16

    The objectives of this study were to characterize the allelic and genotypic frequencies of polymorphisms in the µ-calpain and calpastatin genes, and to assess their association with meat tenderness and animal growth in Nellore cattle. We evaluated 605 Nellore animals at 24 months of age, on average, at slaughter. The polymorphisms were determined for the molecular markers CAPN316, CAPN530, CAPN4751, CAPN4753, and UOGACAST1. Analyses of meat tenderness at 7, 14, and 21 days of maturation were performed in samples of longissimus thoracis obtained between the 12th and 13th rib and sheared using a Warner Bratzler Shear Force. Significant effects were observed for meat tenderness at days 7, 14, and 21 of maturation for the marker CAPN4751, at day 21 for the marker CAPN4753, and at days 14 and 21 for the marker UOGCAST1. For genotypic combinations of markers, the results were significant for the combination CAPN4751/UOGCAST1 in the three maturation periods and CAPN4753/UOGCAST1 at days 14 and 21 of maturation.

  4. Assignment of an essential role for the Neurospora frequency gene in circadian entrainment to temperature cycles.

    Science.gov (United States)

    Pregueiro, Antonio M; Price-Lloyd, Nathan; Bell-Pedersen, Deborah; Heintzen, Christian; Loros, Jennifer J; Dunlap, Jay C

    2005-02-08

    Circadian systems include slave oscillators and central pacemakers, and the cores of eukaryotic circadian clocks described to date are composed of transcription and translation feedback loops (TTFLs). In the model system Neurospora, normal circadian rhythmicity requires a TTFL in which a White Collar complex (WCC) activates expression of the frequency (frq) gene, and the FRQ protein feeds back to attenuate that activation. To further test the centrality of this TTFL to the circadian mechanism in Neurospora, we used low-amplitude temperature cycles to compare WT and frq-null strains under conditions in which a banding rhythm was elicited. WT cultures were entrained to these temperature cycles. Unlike those normal strains, however, frq-null mutants did not truly entrain to the same cycles. Their peaks and troughs always occurred in the cold and warm periods, respectively, strongly suggesting that the rhythm in Neurospora lacking frq function simply is driven by the temperature cycles. Previous reports suggested that a FRQ-less oscillator (FLO) could be entrained to temperature cycles, rather than being driven, and speculated that the FLO was the underlying circadian-rhythm generator. These inferences appear to derive from the use of a phase reference point affected by both the changing waveform and the phase of the oscillation. Examination of several other phase markers as well as results of additional experimental tests indicate that the FLO is, at best, a slave oscillator to the TTFL, which underlies circadian rhythm generation in Neurospora.

  5. Gene-based multiple regression association testing for combined examination of common and low frequency variants in quantitative trait analysis

    Directory of Open Access Journals (Sweden)

    Yun Joo eYoo

    2013-11-01

    Full Text Available Multi-marker methods for genetic association analysis can be performed for common and low frequency SNPs to improve power. Regression models are an intuitive way to formulate multi-marker tests. In previous studies we evaluated regression-based multi-marker tests for common SNPs, and through identification of bins consisting of correlated SNPs, developed a multi-bin linear combination (MLC test that is a compromise between a 1df linear combination test and a multi-df global test. Bins of SNPs in high linkage disequilibrium (LD are identified, and a linear combination of individual SNP statistics is constructed within each bin. Then association with the phenotype is represented by an overall statistic with df as many or few as the number of bins. In this report we evaluate multi-marker tests for SNPs that occur at low frequencies. There are many linear and quadratic multi-marker tests that are suitable for common or low frequency variant analysis. We compared the performance of the MLC tests with various linear and quadratic statistics in joint or marginal regressions. For these comparisons, we performed a simulation study of genotypes and quantitative traits for 85 genes with many low frequency SNPs based on HapMap Phase III. We compared the tests using 1 set of all SNPs in a gene, 2 set of common SNPs in a gene (MAF≥5%, 3 set of low frequency SNPs (1%≤MAF

  6. Frequency of K-RAS and N-RAS Gene Mutations in Colorectal Cancers in Southeastern Iran

    Science.gov (United States)

    Mohsen, Naseri; Ahmadreza, Sebzari; Fatemeh, Haghighi; Fatemeh, Hajipoor; Fariba, Emadian Razavi

    2016-01-09

    Background: K-RAS and N-RAS gene mutations cause resistance to treatment in patients with colorectal cancer. Based on this, awareness of mutation of these genes is considered a clinically important step towards better diagnosis and appropriate treatment. Materials and Methods: Fifty paraffin-embedded blocks of colorectal cancer were obtained from Imam Reza Hospital of Birjand, Iran. Following DNA extraction, the samples were analyzed for common mutations of exons 2, 3 and 4 of KRAS and NRAS genes using real time PCR and pyrosequencing. Results: According to this study, the prevalence of mutations was respectively 28% (14 out of 50) and 2% (1 out of 50) in KRAS and NRAS genes. All the mutations were observed in patients >50 years old. Conclusions: Mutations were found in both KRAS and NRAS genes in colorectal cancers in Iranian patients. Determining the frequency of these mutations in each geographical region may be necessary to benefit from targeted cancer therapy.

  7. [A study of frequency of TNF alpha gene with type 2 diabetes mellitus with chronic periodontitis].

    Science.gov (United States)

    Liu, Bo; Yu, Ning; Tan, Li-si; Liu, Jing-bo; Guo, Yan; Pan, Ya-ping

    2011-04-01

    To detect the frequency of TNF alpha gene in patients of type 2 diabetes mellitus with chronic periodontitis, periodontitis without any systemic diseases and healthy controls. The case series were consisted of 112 patients with moderate, severe type 2 diabetes mellitus with chronic periodontitis, 99 patients with moderate, severe periodontitis without any systemic disease, 50 age- and gender-matched subjects with healthy periodontal conditions were enrolled. Clinical parameters were measured and recorded including probing depth(PD), clinical attachment loss(CAL), bleeding index(BI), and tooth movement(TM). The polymorphism of TNF-α-308 genotype (TNF1/2) was examined after electrophoresis on agarose gel and ethidium bromide staining. The difference between the case and healthy groups was analysed by Chi-square test, the difference in clinical index among groups which had different allele was analyzed for ANOVA with SPSS13.0 software package. We divided DM and CP groups into moderate and severe groups. There were significant difference between severe DM group and severe, moderate CP group, moderate DM group and chronic periodontitis of severe,moderate group. The probing depth and clinical attachment loss of the patients who took TNF-α-308 allele II were significantly higher than the patients who took TNF-α-308 allele I in DM and CP group. TNF-α-308 allele II might increase the susceptivity of periodontitis in population. TNF-α-308 allele II may play an important role in synergistic reaction of periodontitis and type 2 diabetes.

  8. Gene frequency distribution of the BoLA-DRB3 locus in Saavedreño Creole dairy cattle.

    Science.gov (United States)

    Ripoli, M V; Lirón, J P; De Luca, J C; Rojas, F; Dulout, F N; Giovambattista, G

    2004-08-01

    The objective of this study is to describe the gene frequency distribution of the bovine lymphocyte antigen (BoLA)-DRB3 locus in Saavedreño Creole dairy cattle and to compare it with previously reported patterns in other cattle breeds. One hundred and twenty-five Saavedreño Creole dairy cattle were genotyped for the BoLA-DRB3.2 allele by polymerase chain reaction and restriction fragment length polymorphism. Twenty-two out of 53 previously identified BoLA-DRB3.2 alleles were detected, with gene frequencies ranging from 0.4 to 16.8%. Seventy percent of the variation corresponded to the seven most frequent alleles (BoLA-DRB3.2*7, *8, *11, *16, *27, *36, and *37). The studied population exhibits a high degree of expected heterozygosity (he = 0.919). The FIS index did not show significant deviation from Hardy-Weinberg equilibrium. However, the neutrality test showed an even gene frequency distribution. This result could be better explained assuming balancing selection instead of neutral or positive selection for one or a few alleles. In conclusion, the results of this study demonstrated that BoLA-DRB3.2 is a highly polymorphic locus in Saavedreño Creole dairy cattle, with significant variation in allele frequency among cattle breeds.

  9. FCGR3B gene frequencies among ethnic Thai blood donors from a regional hospital in Eastern Thailand.

    Science.gov (United States)

    Kongmaroeng, C; Kumkaen, K

    2015-02-01

    The FCGR3B gene encodes three human neutrophil antigens which consist of HNA-1a, HNA-1b, and HNA-1c. These antigens are encoded by three alleles in the FCGR3B locus: FCGR3B*01, FCGR3B*02, and FCGR3B*03 alleles, respectively. The frequencies of FCGR3B alleles have been reported in different ethnic populations. This study compared the FCGR3B gene frequencies among 230 unrelated healthy Eastern Thai blood donors in Rayong hospital with the previously published studies. The polymerase chain reaction-sequence-specific primers method was performed to determine FCGR3B genotypes. The results showed that the allele frequencies of FCGR3B*01, FCGR3B*02, and FCGR3B*03 were 0.722, 0.274, and 0.009, respectively. The FCGR3B*01 and FCGR3B*02 frequencies found in the Eastern Thais were similar to the previous reports investigating in Northern Thais, Chinese Han, Taiwanese, and Japanese populations. Interestingly, our data showed statistically significant difference (P American, German, and Italian populations. In addition, one FCGR3Bnull , which represents a gene deletion, was also found in this study. This information is important not only for the assessment of neutrophil antibody-mediated clinical conditions and for disease association studies but also for anthropological studies.

  10. Increased frequency of DNA deletions in pink-eyed unstable mice carrying a mutation in the Werner syndrome gene homologue.

    Science.gov (United States)

    Lebel, Michel

    2002-01-01

    Werner syndrome (WS) is a rare autosomal recessive disorder characterized by genomic instability and the premature onset of a number of age-related diseases, including cancers. Accumulating evidence indicates that the WS gene product is involved in resolving aberrant DNA structures that may arise during the process of DNA replication and/or transcription. To estimate the frequency of DNA deletions directly in the skin of mouse embryos, mice with a deletion of part of the murine WRN helicase domain were created. These mutant mice were then crossed to the pink-eyed unstable animals, which have a 70 kb internal duplication at the pink-eyed dilution (p) gene. This report indicates that the frequency of deletion of the duplicated sequence at the p locus is elevated in mice with a mutation in the WRN allele when compared with wild-type mice. In addition, the inhibitor of topoisomerase I camptothecin also increases the frequency of deletion at the p locus. This frequency is even more elevated in WRN mutant mice treated with camptothecin. In contrast, while the inhibition of poly(ADP-ribose) polymerase (PARP) activity by 3-aminobenzamide increases the frequency of DNA deletion, mutant WRN mice are not significantly more sensitive to the inhibition of PARP activity than wild-type animals.

  11. Allelic and genotypic frequencies of ASIP and MC1R genes in four ...

    African Journals Online (AJOL)

    gabriel

    2012-09-27

    Sep 27, 2012 ... DOI: 10.5897/AJB11.4031 ... Although, no routine methods for detection of the genetic basis of the ... Key words: Sheep, coat colour, MC1R gene, ASIP gene, Burkina .... only involves variation in the coding sequence (homo- ... differences in expression of the ASIP gene (Royo et al., ... Molecular Cloning: A.

  12. Bacteriophages of Staphylococcus aureus efficiently package various bacterial genes and mobile genetic elements including SCCmec with different frequencies.

    Science.gov (United States)

    Mašlaňová, Ivana; Doškař, Jiří; Varga, Marian; Kuntová, Lucie; Mužík, Jan; Malúšková, Denisa; Růžičková, Vladislava; Pantůček, Roman

    2013-02-01

    Staphylococcus aureus is a serious human and veterinary pathogen in which new strains with increasing virulence and antimicrobial resistance occur due to acquiring new genes by horizontal transfer. It is generally accepted that temperate bacteriophages play a major role in gene transfer. In this study, we proved the presence of various bacterial genes of the S. aureus COL strain directly within the phage particles via qPCR and quantified their packaging frequency. Non-parametric statistical analysis showed that transducing bacteriophages φ11, φ80 and φ80α of serogroup B, in contrast to serogroup A bacteriophage φ81, efficiently package selected chromosomal genes localized in 4 various loci of the chromosome and 8 genes carried on variable elements, such as staphylococcal cassette chromosome SCCmec, staphylococcal pathogenicity island SaPI1, genomic islands vSaα and vSaβ, and plasmids with various frequency. Bacterial gene copy number per ng of DNA isolated from phage particles ranged between 1.05 × 10(2) for the tetK plasmid gene and 3.86 × 10(5) for the SaPI1 integrase gene. The new and crucial finding that serogroup B bacteriophages can package concurrently ccrA1 (1.16 × 10(4)) and mecA (1.26 × 10(4)) located at SCCmec type I into their capsids indicates that generalized transduction plays an important role in the evolution and emergence of new methicillin-resistant clones.

  13. Frequency of mutations in the genes associated with hereditary sensory and autonomic neuropathy in a UK cohort.

    LENUS (Irish Health Repository)

    Davidson, G L

    2012-08-01

    The hereditary sensory and autonomic neuropathies (HSAN, also known as the hereditary sensory neuropathies) are a clinically and genetically heterogeneous group of disorders, characterised by a progressive sensory neuropathy often complicated by ulcers and amputations, with variable motor and autonomic involvement. To date, mutations in twelve genes have been identified as causing HSAN. To study the frequency of mutations in these genes and the associated phenotypes, we screened 140 index patients in our inherited neuropathy cohort with a clinical diagnosis of HSAN for mutations in the coding regions of SPTLC1, RAB7, WNK1\\/HSN2, FAM134B, NTRK1 (TRKA) and NGFB. We identified 25 index patients with mutations in six genes associated with HSAN (SPTLC1, RAB7, WNK1\\/HSN2, FAM134B, NTRK1 and NGFB); 20 of which appear to be pathogenic giving an overall mutation frequency of 14.3%. Mutations in the known genes for HSAN are rare suggesting that further HSAN genes are yet to be identified. The p.Cys133Trp mutation in SPTLC1 is the most common cause of HSAN in the UK population and should be screened first in all patients with sporadic or autosomal dominant HSAN.

  14. "FAMILIAL DEFECTIVE APOLIPORROTEIN B 100: FREQUENCY OF R3500Q MUTATION OF APOLIPOROTEIN B GENE IN IRANIAN HYPERCHOLESTEROLEMIC PATIENTS"

    Directory of Open Access Journals (Sweden)

    P. Fard-Esfahani

    2005-06-01

    Full Text Available Familial defective apolipoprotein (apo B 100 (FDB causes early-onset coronary heart diseases (CHD. It is produced by R3500Q mutation of the apoB gene resulting in decreased binding of LDL to LDL receptor. We screened the apo B gene for R3500Q mutation in 130 hypercholesterolemic patients, among whom 30 patients met criteria of familial hypercholesterolemia (FH. The prevalence of R3500Q allele in this patient population was 0%. To obtain better estimation of mutation frequency, a broad survey is needed.

  15. Unusually high frequency of genes encoding vegetative insecticidal proteins in an Australian Bacillus thuringiensis collection.

    Science.gov (United States)

    Beard, Cheryl E; Court, Leon; Boets, Annemie; Mourant, Roslyn; Van Rie, Jeroen; Akhurst, Raymond J

    2008-09-01

    Of 188 Australian Bacillus thuringiensis strains screened for genes encoding soluble insecticidal proteins by polymerase chain reaction/restriction-length fragment polymorphism (RFLP) analysis, 87% showed the presence of such genes. Although 135 isolates (72%) produced an RFLP pattern identical to that expected for vip3A genes, 29 isolates possessed a novel vip-like gene. The novel vip-like gene was cloned from B. thuringiensis isolate C81, and sequence analysis demonstrated that it was 94% identical to the vip3Ba1 gene. The new gene was designated vip3Bb2. Cell-free supernatants from both the B. thuringiensis strain C81 and from Escherichia coli expressing the Vip3Bb2 protein were toxic for the cotton bollworm, Helicoverpa armigera.

  16. Frequency of the Hemochromatosis Gene (HFE Variants in a Jordanian Arab Population and in Diabetics from the Same Region

    Directory of Open Access Journals (Sweden)

    Asem Alkhateeb

    2009-01-01

    Full Text Available Hereditary HFE-linked hemochromatosis is a frequent recessive disorder among individuals of northern European ancestry. The clinical characteristic of this disease is the gradual accumulation of iron in internal organs, which ultimately may lead to organ damage and death. Three allelic variants of HFE gene have been correlated with hereditary hemochromatosis: C282Y is significantly associated with hereditary hemochromatosis in populations of Celtic origin, H63D and S65C are associated with milder form of iron overload. In this study we performed mutation analysis to identify allele frequency of the three variants of HFE gene in Jordanian Arab population, to assess deviations of these frequencies from those detected elsewhere, and to determine if there is an increased frequency of these variants in a diabetic population (Type 2 diabetes from the same area. DNA was extracted from blood samples of 440 individuals attending King Abdullah University Hospital for ambulatory services. We used polymerase chain reaction (PCR to amplify exons 2 and 4 of the HFE gene then restriction fragment length polymorphism (RFLP method to detect the variants. There were neither homozygous nor heterozygous for C282Y variant. For the H63D variant, 0.68% were homozygous and 21.1% were heterozygous. For the S65C variant, there were no homozygous and 0.23% were heterozygous. Allelic frequencies were, 0%, 11.25%, and 0.11% for C282Y, H63D, and S65C, respectively. Our samples were subdivided into two categories of type 2 diabetic (89 cases and controls (blood donors, 204 cases and compared with regard to the H63D variant. Both groups did not have homozygous H63D variant. H63D heterozygous in diabetics were 23.60% and in blood donor controls 22.55%. Allelic frequency of the mutant H63D allele was 11.80% in diabetics and 11.27% for the blood donor controls. This is the first study to show the frequency of the three hemochromatosis gene variants in Jordan with the interesting

  17. The use of high-frequency ultrasound imaging and biofluorescence for in vivo evaluation of gene therapy vectors

    OpenAIRE

    Ingram, N.; Macnab, SA; Marston, G; Scott, N.; Carr, IM; Markham, AF; Whitehouse, A; Coletta, PL

    2013-01-01

    Background: Non-invasive imaging of the biodistribution of novel therapeutics including gene therapy vectors in animal models is essential. Methods: This study assessed the utility of high-frequency ultrasound (HF-US) combined with biofluoresence imaging (BFI) to determine the longitudinal impact of a Herpesvirus saimiri amplicon on human colorectal cancer xenograft growth. Results: HF-US imaging of xenografts resulted in an accurate and informative xenograft volume in a longitudinal study. T...

  18. Acute impact of intermittent pneumatic leg compression frequency on limb hemodynamics, vascular function, and skeletal muscle gene expression in humans.

    Science.gov (United States)

    Sheldon, Ryan D; Roseguini, Bruno T; Thyfault, John P; Crist, Brett D; Laughlin, M H; Newcomer, Sean C

    2012-06-01

    The mechanisms by which intermittent pneumatic leg compression (IPC) treatment effectively treats symptoms associated with peripheral artery disease remain speculative. With the aim of gaining mechanistic insight into IPC treatment, the purpose of this study was to investigate the effect of IPC frequency on limb hemodynamics, vascular function, and skeletal muscle gene expression. In this two study investigation, healthy male subjects underwent an hour of either high-frequency (HF; 2-s inflation/3-s deflation) or low-frequency (LF; 4-s inflation/16-s deflation) IPC treatment of the foot and calf. In study 1 (n = 11; 23.5 ± 4.7 yr), subjects underwent both HF and LF treatment on separate days. Doppler/ultrasonography was used to measure popliteal artery diameter and blood velocity at baseline and during IPC treatment. Flow-mediated dilation (FMD) and peak reactive hyperemia blood flow (RHBF) were determined before and after IPC treatment. In study 2 (n = 19; 22.0 ± 4.6 yr), skeletal muscle biopsies were taken from the lateral gastrocnemius of the treated and control limb at baseline and at 30- and 150-min posttreatment. Quantitative PCR was used to assess mRNA concentrations of genes associated with inflammation and vascular remodeling. No treatment effect on vascular function was observed. Cuff deflation resulted in increased blood flow (BF) and shear rate (SR) in both treatments at the onset of treatment compared with baseline (P inflation. IPC decreased the mRNA expression of cysteine-rich protein 61 from baseline and controls (P <0 .01) and connective tissue growth factor from baseline (P < 0.05) in a frequency-dependent manner. In conclusion, a single session of IPC acutely impacts limb hemodynamics and skeletal muscle gene expression in a frequency-dependent manner but does not impact vascular function.

  19. Whole-genome gene expression modifications associated with nitrosamine exposure and micronucleus frequency in human blood cells

    DEFF Research Database (Denmark)

    Hebels, Dennie G A J; Jennen, Danyel G J; van Herwijnen, Marcel H M

    2011-01-01

    association between MN frequency and urinary NOCs (r = 0.41, P = 0.025) and identified modifications in among others cytoskeleton remodeling, cell cycle, apoptosis and survival, signal transduction, immune response, G-protein signaling and development pathways, which indicate a response to NOC......N-nitroso compounds (NOCs) are suspected human carcinogens and relevant in human exposure. NOCs also induce micronuclei (MN) formation in vivo. Since lymphocytic MN represent a validated biomarker of human cancer risk, establishing a link between NOC exposure and MN frequency in humans...... for analysing such potentially carcinogenic gene expression and MN formation events in target organs. To assess NOC exposure, urine samples were analysed for marker nitrosamines. NOC excretion levels and MN frequency were subsequently linked to peripheral blood transcriptomics. We demonstrated a significant...

  20. Update on the frequency of Ile1016 mutation in voltage-gated sodium channel gene of Aedes aegypti in Mexico.

    Science.gov (United States)

    Siller, Quetzaly; Ponce, Gustavo; Lozano, Saul; Flores, Adriana E

    2011-12-01

    We analyzed 790 Aedes aegypti from 14 localities of Mexico in 2009 to update information on the frequency of the Ile1016 allele in the voltage-gated sodium channel gene that confers resistance to pyrethroids and DDT. The Ile1016 mutation was present in all 17 collections, and was close to fixation in Acapulco (frequency = 0.97), Iguala (0.93), and San Nicolas (0.90). Genotypes at the 1016 locus were not in Hardy-Weinberg proportions in collections from Panuco, Veracruz, Cosoleacaque, Coatzacoalcos, Tantoyuca, and Monterrey due in every case to an excess of homozygotes. The high frequencies of this mutation in Ae. aegypti are probably due to selection pressure from pyrethroid insecticides, particularly permethrin, which has been used in mosquito control programs for >10 years in Mexico.

  1. Frequencies of virulence genes and pulse field gel electrophoresis fingerprints in Escherichia coli isolates from canine pyometra.

    Science.gov (United States)

    Maluta, Renato P; Borges, Clarissa A; Beraldo, Lívia G; Cardozo, Marita V; Voorwald, Fabiana A; Santana, André M; Rigobelo, Everlon C; Toniollo, Gilson H; Avila, Fernando A

    2014-11-01

    Escherichia coli is the most common bacterial agent isolated from canine pyometra. The frequencies of 24 virulence genes and pulsed field gel electrophoresis (PFGE) profiles were determined for 23 E. coli isolates from cases of canine pyometra in Brazil. The frequencies of virulence genes were 91.3% fimH, 91.3% irp-2, 82.6% fyuA, 56.5% iroN, 47.8% traT, 39.1% usp, 34.8% sfaD/E, 34.8% tsh, 30.4% papC, 30.4% hlyA, 26.1% papGIII, 26.1% cnf-1, 21.7% papE/F, 21.7% iss, 17.4% iutA, 17.4% ompT, 17.4% cvaC, 17.4% hlyF, 17.4% iucD, 13.0% iucC, 13.0% astA, 4.3% papGII, 0% afaB/C and 0% papGI. The high frequency of yersiniabactin (fyuA and irp2) and salmochelin (iroN) genes suggests that iron uptake systems might be important in the pathogenesis of canine pyometra. PFGE profiles of 19 isolates were heterogeneous, confirming that E. coli isolates from canine pyometra are unlikely to be epidemic clones.

  2. Frequency of 3' VNTR Polymorphism in the Dopamine Transporter Gene SLC6A3 in Humans Predisposed to Antisocial Behavior.

    Science.gov (United States)

    Cherepkova, E V; Aftanas, L I; Maksimov, N; Menshanov, P N

    2016-11-01

    Predisposition to antisocial behavior can be related to the presence of certain polymorphic variants of genes encoding dopaminergic system proteins. We studied the frequencies of allele variants and genotypes of variable number tandem repeat polymorphism in 3' untranslated region (3' VTNR) of the dopaminergic transporter SLC6A3 gene in Caucasian men committed socially dangerous violent and non-violent crimes. Alleles with 9 and 10 repeats were most frequent in both the control group and group of men predisposed to antisocial behavior. At the same time, the 10/10 genotype was more frequently observed in the group of men prone to antisocial non-violent behavior. Hence, the presence of certain variants of 3' VTNR polymorphism of SLC6A3 gene in men is associated with predisposition to certain forms of antisocial behavior.

  3. Genetic Adaptation to Climate in White Spruce Involves Small to Moderate Allele Frequency Shifts in Functionally Diverse Genes.

    Science.gov (United States)

    Hornoy, Benjamin; Pavy, Nathalie; Gérardi, Sébastien; Beaulieu, Jean; Bousquet, Jean

    2015-11-11

    Understanding the genetic basis of adaptation to climate is of paramount importance for preserving and managing genetic diversity in plants in a context of climate change. Yet, this objective has been addressed mainly in short-lived model species. Thus, expanding knowledge to nonmodel species with contrasting life histories, such as forest trees, appears necessary. To uncover the genetic basis of adaptation to climate in the widely distributed boreal conifer white spruce (Picea glauca), an environmental association study was conducted using 11,085 single nucleotide polymorphisms representing 7,819 genes, that is, approximately a quarter of the transcriptome.Linear and quadratic regressions controlling for isolation-by-distance, and the Random Forest algorithm, identified several dozen genes putatively under selection, among which 43 showed strongest signals along temperature and precipitation gradients. Most of them were related to temperature. Small to moderate shifts in allele frequencies were observed. Genes involved encompassed a wide variety of functions and processes, some of them being likely important for plant survival under biotic and abiotic environmental stresses according to expression data. Literature mining and sequence comparison also highlighted conserved sequences and functions with angiosperm homologs.Our results are consistent with theoretical predictions that local adaptation involves genes with small frequency shifts when selection is recent and gene flow among populations is high. Accordingly, genetic adaptation to climate in P. glauca appears to be complex, involving many independent and interacting gene functions, biochemical pathways, and processes. From an applied perspective, these results shall lead to specific functional/association studies in conifers and to the development of markers useful for the conservation of genetic resources. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular

  4. Low frequency of ESRRA-C11orf20 fusion gene in ovarian carcinomas.

    OpenAIRE

    Francesca Micci; Ioannis Panagopoulos; Jim Thorsen; Ben Davidson; Claes Gøran Tropé; Sverre Heim

    2014-01-01

    The identification of recurrent gene fusions in common epithelial cancers--for example, TMPRSS2/ERG in prostate cancer and EML4/ALK in nonsmall cell lung carcinomas--has raised the question of whether fusion genes are pathogenetically important also in ovarian carcinomas. The first recurrent fusion transcript in serous ovarian carcinomas was reported by Salzman et al. in 2011, who used deep paired-end sequencing to detect the fusion gene ESRRA-C11orf20 in 10 out of 67 (15%) serous ovarian car...

  5. Correlation of Shiga Toxin Gene Frequency with Commonly Used Microbial Indicators of Recreational Water Quality▿ †

    Science.gov (United States)

    Smith, Cody J.; Olszewski, Adam M.; Mauro, Steven A.

    2009-01-01

    Shiga toxin (Stx) genes produce proteins that are pathogenic to humans, leading to severe gastrointestinal illness. This work focuses on examining the abundance and distribution of stx genes in relation to common microbial indicators in beach water and streams in the vicinity of Presque Isle State Park in Erie, PA. By use of quantitative PCR, the relative abundance levels of stx DNA in over 700 samples in the sampling area were determined. The results demonstrate that the abundance and distribution of stx genes are variable and do not correlate with the abundance of Escherichia coli bacteria, enterococci, or viral particles. These results suggest that microbial indicators of water quality are not adequate in predicting the occurrence of organisms that harbor stx genes and highlight the need for standardized pathogen-specific detection protocols for waters utilized for recreational swimming. PMID:19011065

  6. Effects of AC/DC magnetic fields, frequency, and nanoparticle aspect ratio on cellular transfection of gene vectors

    Science.gov (United States)

    Ford, Kris; Mair, Lamar; Fisher, Mike; Rowshon Alam, Md.; Juliano, Rudolph; Superfine, Richard

    2008-10-01

    In order to make non-viral gene delivery a useful tool in the study and treatment of genetic disorders, it is imperative that these methodologies be further refined to yield optimal results. Transfection of magnetic nanoparticles and nanorods are used as non-viral gene vectors to transfect HeLa EGFP-654 cells that stably express a mutated enhanced green fluorescent protein (EGFP) gene. We deliver antisense oligonucleotides to these cells designed to correct the aberrant splicing caused by the mutation in the EGFP gene. We also transfect human bronchial endothelial cells and immortalized WI-38 lung cells with pEGFP-N1 vectors. To achieve this we bind the genes to magnetic nanoparticles and nanorods and introduce magnetic fields to effect transfection. We wish to examine the effects of magnetic fields on the transfection of these particles and the benefits of using alternating (AC) magnetic fields in improving transfection rates over direct (DC) magnetic fields. We specifically look at the frequency dependence of the AC field and particle aspect ratio as it pertains to influencing transfection rate. We posit that the increase in angular momentum brought about by the AC field and the high aspect ratio of the nanorod particles, is vital to generating the force needed to move the particle through the cell membrane.

  7. Manipulation of cell cycle progression can counteract the apparent loss of correction frequency following oligonucleotide-directed gene repair

    Directory of Open Access Journals (Sweden)

    Kmiec Eric B

    2007-02-01

    Full Text Available Abstract Background Single-stranded oligonucleotides (ssODN are used routinely to direct specific base alterations within mammalian genomes that result in the restoration of a functional gene. Despite success with the technique, recent studies have revealed that following repair events, correction frequencies decrease as a function of time, possibly due to a sustained activation of damage response signals in corrected cells that lead to a selective stalling. In this study, we use thymidine to slow down the replication rate to enhance repair frequency and to maintain substantial levels of correction over time. Results First, we utilized thymidine to arrest cells in G1 and released the cells into S phase, at which point specific ssODNs direct the highest level of correction. Next, we devised a protocol in which cells are maintained in thymidine following the repair reaction, in which the replication is slowed in both corrected and non-corrected cells and the initial correction frequency is retained. We also present evidence that cells enter a senescence state upon prolonged treatment with thymidine but this passage can be avoided by removing thymidine at 48 hours. Conclusion Taken together, we believe that thymidine may be used in a therapeutic fashion to enable the maintenance of high levels of treated cells bearing repaired genes.

  8. Comparison of CpG island methylator phenotype (CIMP frequency in colon cancer using different probe- and gene-specific scoring alternatives on recommended multi-gene panels.

    Directory of Open Access Journals (Sweden)

    Marianne Berg

    Full Text Available BACKGROUND: In colorectal cancer a distinct subgroup of tumours demonstrate the CpG island methylator phenotype (CIMP. However, a consensus of how to score CIMP is not reached, and variation in definition may influence the reported CIMP prevalence in tumours. Thus, we sought to compare currently suggested definitions and cut-offs for methylation markers and how they influence CIMP classification in colon cancer. METHODS: Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA, with subsequent fragment analysis, was used to investigate methylation of tumour samples. In total, 31 CpG sites, located in 8 different genes (RUNX3, MLH1, NEUROG1, CDKN2A, IGF2, CRABP1, SOCS1 and CACNA1G were investigated in 64 distinct colon cancers and 2 colon cancer cell lines. The Ogino gene panel includes all 8 genes, in addition to the Weisenberger panel of which only 5 of the 8 genes included were investigated. In total, 18 alternative combinations of scoring of CIMP positivity on probe-, gene-, and panel-level were analysed and compared. RESULTS: For 47 samples (71%, the CIMP status was constant and independent of criteria used for scoring; 34 samples were constantly scored as CIMP negative, and 13 (20% consistently scored as CIMP positive. Only four of 31 probes (13% investigated showed no difference in the numbers of positive samples using the different cut-offs. Within the panels a trend was observed that increasing the gene-level stringency resulted in a larger difference in CIMP positive samples than increasing the probe-level stringency. A significant difference between positive samples using 'the most stringent' as compared to 'the least stringent' criteria (20% vs 46%, respectively; p<0.005 was demonstrated. CONCLUSIONS: A statistical significant variation in the frequency of CIMP depending on the cut-offs and genes included in a panel was found, with twice as many positives samples by least compared to most stringent definition

  9. Frequency of the Val1016Ile mutation on the kdr gene in Aedes aegypti (Diptera: Culicidae) in south Brazil.

    Science.gov (United States)

    Collet, M L; Frizzo, C; Orlandin, E; Rona, L D P; Nascimento, J C; Montano, M A E; Müller, G A; Wagner, G

    2016-11-21

    Recently, the number of Aedes aegypti foci has increased in west of Santa Catarina, south Brazil, which has increased concern regarding mosquito-borne disease outbreaks such as dengue fever, Zika virus, and chikungunya. Therefore, it is important to monitor genetic resistance to insecticides through "knockdown resistance". Homozygosity (Ile/Ile) at position 1016 in the coding region of a voltage-dependent sodium channel gene (Nav) may induce resistance to pyrethroid insecticides. We evaluated the frequency of these alleles in A. aegypti in west Santa Catarina. In total, 349 specimens were obtained from the microregions of Joaçaba (31), Concórdia (35), Chapecó (154), and São Miguel do Oeste (129). We found that 109 individuals (31.0%) were homozygous for Val/Val, 102 (29.0%) were heterozygous for Val/Ile, and 138 (40.0%) were homozygous for Ile/Ile. The allele frequencies were similar for Val (0.455) and Ile (0.545). Joaçaba and Concórdia had the highest mutant allele frequencies (0.825 and 0.685, respectively). Therefore, these populations should be monitored for increases in pyrethroid resistance. The São Miguel do Oeste and Chapecó populations had similar frequencies of Val and Ile and were not in Hardy-Weinberg equilibrium, suggesting that a selection pressure or other evolutionary force has occurred. In conclusion, the observed frequency of Ile/Ile homozygous individuals in the region studied requires attention, because the implementation of controls using pyrethroid may increase the frequency of the mutant allele through the selection of resistant populations.

  10. Frequencies of the Common Mefv Gene Mutations in Adiyaman, Southeast Anatolia, Turkey

    Directory of Open Access Journals (Sweden)

    Korkmaz D. T.

    2014-12-01

    Full Text Available Familial Mediterranean fever (FMF is an autosomal recessive disorder characterized by fever and serosal inflammation. The reasons for the disorder are mutations in the Mediterranean fever (MEFV gene; the most common of which are M694V, M680I, M694I and V726A. In this study, we aimed to screen these common mutations of the MEFV gene and then determine the prevalence of FMF according to these mutations in Adıyaman, Southeast Anatolia, Turkey. Seven hundred and sixty-seven healthy individuals from the region of Adıyaman participated in the study. Polymerase chain reaction-amplification refractory mutation system (PCR-ARMS methods were used to determine the common mutations of the MEFV gene. Twenty-six (3.9% individuals had only one mutation in the MEFV gene, 25 individuals were heterozygous and one person was homozygous for the V726A mutation (0.15%. In the present study, the V726A mutation (50.0% was the most frequent, followed by M694V (38.5%, M680I (7.7% and M694I (3.8%. It was seen that the carrier rate was very low and the prevalence of FMF was 0.15%, according to the common mutations of the MEFV gene in Adıyaman, Southeast Anatolia, Turkey.

  11. Changes in disease gene frequency over time with differential genotype fitness and various control strategies

    NARCIS (Netherlands)

    Thompson, P.N.; Heesterbeek, J.A.P.; Arendonk, van J.A.M.

    2006-01-01

    A spreadsheet model was constructed to describe the change in allelic frequency over time for a lethal recessive mutation in an animal population. The model allowed relative fitness to differ between genotypes, between sexes, and over time. Whereas a lethal recessive allele is naturally eliminated v

  12. Changes in disease gene frequency over time with differential genotypic fitness and various control strategies

    NARCIS (Netherlands)

    Thompson, P.N.; Heesterbeek, J.A.P.; Arendonk, J.A.M. van

    2006-01-01

    A spreadsheet model was constructed to describe the change in allelic frequency over time for a lethal recessive mutation in an animal population. The model allowed relative fitness to differ between genotypes, between sexes, and over time. Whereas a lethal recessive allele is naturally eliminated v

  13. Allele frequency and likely impact of the glycogen branching enzyme deficiency gene in Quarter Horse and Paint Horse populations.

    Science.gov (United States)

    Wagner, M L; Valberg, S J; Ames, E G; Bauer, M M; Wiseman, J A; Penedo, M C T; Kinde, H; Abbitt, B; Mickelson, J R

    2006-01-01

    Glycogen Branching Enzyme Deficiency (GBED), a fatal condition recently identified in fetuses and neonatal foals of the Quarter Horse and Paint Horse lineages, is caused by a nonsense mutation in codon 34 of the GBE1 gene, which prevents the synthesis of a functional GBE protein and severely disrupts glycogen metabolism. The aims of this project were to determine the mutant GBE1 allele frequency in random samples from the major relevant horse breeds, as well as the frequency with which GBED is associated with abortion and early neonatal death using the tissue archives from veterinary diagnostic laboratories. The mutant GBE1 allele frequency in registered Quarter Horse, Paint Horse, and Thoroughbred populations was 0.041, 0.036, and 0.000, respectively. Approximately 2.5% of fetal and early neonatal deaths in Quarter Horse-related breeds submitted to 2 different US diagnostic laboratories were homozygous for the mutant GBE1 allele, with the majority of these being abortions. Retrospective histopathology of the homozygotes detected periodic acid Schiff's (PAS)-positive inclusions in the cardiac or skeletal muscle, which is characteristic of GBED, in 8 out of the 9 cases. Pedigree and genotype analyses supported the hypothesis that GBED is inherited as a simple recessive trait from a single founder. The frequency with which GBED is associated with abortion and neonatal mortality in Quarter Horse-related breeds makes the DNA-based test valuable in determining specific diagnoses and designing matings that avoid conception of a GBED foal.

  14. Variation in the gene frequencies of three generations of humans from Monterrey, Nuevo León, Mexico.

    Science.gov (United States)

    Cerda-Flores, R M; Garza-Chapa, R

    1989-04-01

    Allele frequencies for the ABO, Rh, MNSs, Duffy, Kidd, Lutheran, P and Lewis blood group systems in 207 persons whose 4 grandparents were born in the Monterrey Metropolitan area (MMA), grouped into 3 generations, were ascertained along with other related population from the MMA, Mestizos from Saltillo, Coahuila and Tlaxcala, and from the populations thought to have contributed to their genetic constitution (native Mexican Indians and Spanish). Genetic admixture and distance estimates were calculated. Gene frequencies of the three generations from MMA are intermediate to those of the ancestral populations, indicating that they are Mestizo but with a genetic structure different from Mestizos of Saltillo and Tlaxcala. Both genetic admixture and distance estimates indicate that the oldest generation exhibits the greatest Spanish influence which decreases in the youngest generation and in the other MMA populations as a result of the immigration from the central states of Mexico.

  15. The frequency of polymorphic variants of filaggrin gene and clinical atopic dermatitis

    Directory of Open Access Journals (Sweden)

    Agata Filipowska-Grońska

    2016-02-01

    Full Text Available Introduction: As far as pathogenesis of the atopic dermatitis (AD is concerned, the roles of an impaired epidermal barrier and cornified cell envelope are widely emphasized. Aim : The assessment of mutations of the filaggrin gene and their connection with the clinical picture of AD as well as selected allergological and environmental indicators. Material and methods: 105 patients with diagnosed AD on the basis of diagnostic criteria were included. For every patient of the examined group, quantitative determination of the total concentration of IgE and the concentration of IgE antibodies to selected allergens were examined. For all patients, studies were performed by means of analysis of two genomic gene variants of profilaggrin (FLG – R501X and 2282del4. Results : Loss-of-function mutations in the filaggrin gene were shown in 12 (11.4% patients in the examined group. All patients in the study group who developed one of the tested loss-of-function mutations in the filaggrin gene demonstrated an extrinsic, allergic form of atopic dermatitis. A significant association (p = 0.0002 between the presence of one of the tested loss-of-function mutations in the filaggrin gene and elevated levels of total concentration of immunoglobulin E was shown. Conclusions : Patients with AD of null mutations in the filaggrin gene demonstrate a relationship with the total and specific concentration of immunoglobulin E, specifically higher concentrations of IgE against aeroallergens and alimentary allergens as well as elevated levels of total immunoglobulin E.

  16. The Frequency of Methicillin-Resistant Staphylococcus aureus and Coagulase Gene Polymorphism in Egypt

    Directory of Open Access Journals (Sweden)

    Hend M. Abdulghany

    2014-01-01

    Full Text Available The current study aimed to use Coagulase gene polymorphism to identify methicillin-resistant Staphylococcus aureus (MRSA subtypes isolated from nasal carriers in Minia governorate, Egypt, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 400 specimens were collected from nasal carriers in Minia governorate, Egypt, between March 2012 and April 2013. Fifty-eight strains (14.5% were isolated and identified by standard microbiological methods as MRSA. The identified isolates were tested by Coagulase gene RFLP typing. Out of 58 MRSA isolates 15 coa types were classified, and the amplification products showed multiple bands (1, 2, 3, 4, 5, and 8 bands. Coagulase gene PCR-RFLPs exhibited 10 patterns that ranged from 1 to 8 fragments with AluI digestion. Antimicrobial susceptibility testing with a panel of 8 antimicrobial agents showed 6 different antibiotypes. Antibiotype 1 was the most common phenotype with 82.7%. The results have demonstrated that many new variants of the coa gene are present in Minia, Egypt, different from those reported in the previous studies. So surveillance of MRSA should be continued.

  17. Frequency of mutations in Mediterranean fever gene, with gender and genotype–phenotype correlations in a Turkish population

    Indian Academy of Sciences (India)

    Salih Coşkun; Serkan Kurtgöz; Ece Keskin; Ferah Sönmez; Gökay Bozkurt

    2015-12-01

    Familial Mediterranean fever (FMF) is the most common hereditary inflammatory periodic disease, characterized by recurrent episodes of fever, abdominal pain, synovitis and pleurisy. The aim of this study was to determine the frequency and distribution of Mediterranean fever () gene mutations and to investigate the clinical characteristics and genotype–phenotype correlation in patients with FMF in Aydın, a province in western Anatolia, Turkey. Therefore, we retrospectively analysed gene mutations in 383 patients with suspected FMF and the clinical features of 327 among them. The gene mutations were investigated using the reverse dot-blot hybridization technique. We detected 26 different genotypes and 11 different mutations. The most common mutations in our cohort were p.M694V (41.15%), p.E148Q (20.35%), p.M680I(G/C) (12.39%) and p.R761H (9.73%). Abdominal pain (86.2%), fever (80.7%), arthralgia (57.2%), vomiting (36.1%), arthritis (34.6%), fatigue (31.5%), anorexia (22.9%) and chest pain (19.0%) were the most prevalent clinical features in our patients. This is the first study from Aydın in which the distribution of gene mutations and clinical features were evaluated in patients with FMF. We found that the most common mutation was p.M694V in our region, while the frequency of the p.R761H mutation was higher compared to other regions of Turkey with respect to extracted data from previous similar studies. Presented results supported the clinical findings in the literature that the homozygous p.M694V and compound heterozygous genotype were associated with more severe courses in FMF patients.

  18. Ku70 and ku80 null mutants improve the gene targeting frequency in Monascus ruber M7.

    Science.gov (United States)

    He, Yi; Liu, Qingpei; Shao, Yanchun; Chen, Fusheng

    2013-06-01

    Normally, gene targeting by homologous recombination occurs rarely during a transformation process since non-homologous recombination is predominant in filamentous fungi. In our previous researches, the average gene replacement frequency (GRF) in Monascus ruber M7 was as low as 15 %. To develop a highly efficient gene targeting system for M. ruber M7, two M. ruber M7 null mutants of ku70 (MrΔku70) and ku80 (MrΔku80) were constructed which had no apparent defects in the development including vegetative growth, colony phenotype, microscopic morphology and spore yield compared with M. ruber M7. In addition, the production of some significant secondary metabolites such as pigments and citrinin had no differences between the two disruptants and the wild-type strain. Further results revealed that the GRFs of triA (encoding a putative acetyltransferase) were 42.2 % and 61.5 % in the MrΔku70 and MrΔku80 strains, respectively, while it was only about 20 % in M. ruber M7. Furthermore, GRFs of these two disruptants at other loci (the pigE, fmdS genes in MrΔku70 and the ku70 gene in MrΔku80) were investigated, and the results indicated that GRFs in the MrΔku70 strain and the MrΔku80 strain were doubled and tripled compared with that in M. ruber M7, respectively. Therefore, the ku70 and ku80 null mutants of M. ruber M7, especially the ku80-deleted strain, will be excellent hosts for efficient gene targeting.

  19. Mannose-binding lectin 2 (MBL2 gene polymorphisms do not influence frequency of infections in chronic lymphocytic leukemia patients

    Directory of Open Access Journals (Sweden)

    Katarina Holanda

    2014-01-01

    Full Text Available Background: Infectious complications represent the main cause of morbidity and mortality in chronic lymphocytic leukemia. It has been reported that polymorphisms of the mannosebinding lectin 2 (MBL2 genes are correlated with MBL protein serum levels and, consequently, are associated with the development of infectious diseases. Objective: The purpose of this study was to investigate the possible association between MBL2 gene polymorphisms and risk of infection in chronic lymphocytic leukemia patients. Methods: Peripheral blood samples from 116 chronic lymphocytic leukemia patients were collected; after genomic DNA extraction, real time polymerase chain reaction was used to determine the polymorphisms of the promoter region and exon 1 of the MBL2 gene. Results: A high frequency of Binet stage A (p-value = 0.005 and absence of splenomegaly (p-value = 0.002 were observed in patients with no infection; however, variant alleles/ genotypes and haplotypes of this gene had no impact on the risk of infection. Conclusion: To the authors' knowledge, this is the first study describing the association between MBL2 polymorphisms and infectious disease in chronic lymphocytic leukemia. Although it was not possible to demonstrate any influence of MBL2 polymorphisms as a genetic modulator of infection in chronic lymphocytic leukemia, the authors believe that the present data are clinically relevant and provide the basis for future studies.

  20. The frequency of a disease-causing point mutation in the gene coding for medium-chain acyl-CoA dehydrogenase in sudden infant death syndrome

    DEFF Research Database (Denmark)

    Banner, Jytte; Gregersen, N; Kølvraa, S

    1993-01-01

    syndrome is still a matter of controversy. The present study investigated 120 well-defined cases of sudden infant death syndrome in order to detect the frequency of the most common disease-causing point mutation in the gene coding for medium-chain acyl-CoA dehydrogenase (G985) compared with the frequency...

  1. Frequency of virulence genes in mixed infections with Helicobacter pylori strains from a Mexican population

    Directory of Open Access Journals (Sweden)

    R. González-Vázquez

    2016-01-01

    Conclusions: The Fisher's exact test did not support a significant association between clinical outcome and genotype. The main circulating genotypes in the Mexican population studied were: cagA+, vacAs1, and vacAm1. Multiplex PCR can be used as a screening test for H. pylori strains. Furthermore, the cagE gene is a good marker for identifying cag-PAI positive strains.

  2. Influence of DNA repair gene polymorphisms of hOGG1, XRCC1, XRCC3, ERCC2 and the folate metabolism gene MTHFR on chromosomal aberration frequencies.

    Science.gov (United States)

    Skjelbred, Camilla Furu; Svendsen, Marit; Haugan, Vera; Eek, Anette Kildal; Clausen, Kjell Oskar; Svendsen, Martin Veel; Hansteen, Inger-Lise

    2006-12-01

    We have studied the effect of genetic polymorphisms in the DNA repair genes hOGG1, XRCC1, XRCC3, ERCC2 and the MTHFR gene in the folate metabolism on the frequencies of cells with chromosomal aberrations (CA), chromosome-type aberrations (CSA), chromatid-type aberrations (CTA), chromatid breaks (CTB) and chromatid gaps (CTG) scored in peripheral blood lymphocytes from 651 Norwegian subjects of Caucasian descendant. DNA was extracted from fixed cell suspensions. The log-linear Poisson regression model was used for the combined data which included age, smoking, occupational exposure and genotype for 449 subjects. Our results suggest that individuals carrying the hOGG1 326Cys or the XRCC1 399Gln allele have an increased risk of chromosomal damage, while individuals carrying the XRCC1 194Trp or the ERCC2 751Gln allele have a reduced risk regardless of smoking habits and age. Individuals carrying the XRCC1 280His allele had an increased risk of CSA which was only apparent in non-smokers. This was independent of age. A protective effect of the XRCC3 241Met allele was only found in the older age group in non-smokers for CA, CSA and CTA, and in smokers for CSA. In the youngest age group, the opposite effect was found, with an increased risk for CA, CTA and CTG in smokers. Carrying the MTHFR 222Val allele gave an increased risk for chromosome and chromatid-type aberrations for both non-smokers and smokers, especially for individuals in the older age group, and with variable results in the youngest age group. The variables included in the different regression models accounted, however, for only 4-10% of the variation. The frequency ratio for CTG was significantly higher than for CTA and CTB for only 7 of the 43 comparisons performed. Some of the gap frequencies diverge from the trend in the CA, CSA, CTA and CTB results.

  3. Deep sequencing of the murine Igh repertoire reveals complex regulation of non-random V gene rearrangement frequencies

    Science.gov (United States)

    Choi, Nancy M.; Loguercio, Salvatore; Verma-Gaur, Jiyoti; Degner, Stephanie C.; Torkamani, Ali; Su, Andrew I.; Oltz, Eugene M.; Artyomov, Maxim; Feeney, Ann J.

    2013-01-01

    A diverse antibody repertoire is formed through the rearrangement of V, D, and J segments at the immunoglobulin heavy chain (Igh) loci. The C57BL/6 murine Igh locus has over 100 functional VH gene segments that can recombine to a rearranged DJH. While the non-random usage of VH genes is well documented, it is not clear what elements determine recombination frequency. To answer this question we conducted deep sequencing of 5′-RACE products of the Igh repertoire in pro-B cells, amplified in an unbiased manner. ChIP-seq results for several histone modifications and RNA polymerase II binding, RNA-seq for sense and antisense non-coding germline transcripts, and proximity to CTCF and Rad21 sites were compared to the usage of individual V genes. Computational analyses assessed the relative importance of these various accessibility elements. These elements divide the Igh locus into four epigenetically and transcriptionally distinct domains, and our computational analyses reveal different regulatory mechanisms for each region. Proximal V genes are relatively devoid of active histone marks and non-coding RNA in general, but having a CTCF site near their RSS is critical, suggesting that being positioned near the base of the chromatin loops is important for rearrangement. In contrast, distal V genes have higher levels of histone marks and non-coding RNA, which may compensate for their poorer RSSs and for being distant from CTCF sites. Thus, the Igh locus has evolved a complex system for the regulation of V(D)J rearrangement that is different for each of the four domains that comprise this locus. PMID:23898036

  4. Linguistic tone is related to the population frequency of the adaptive haplogroups of two brain size genes, ASPM and Microcephalin.

    Science.gov (United States)

    Dediu, Dan; Ladd, D Robert

    2007-06-26

    The correlations between interpopulation genetic and linguistic diversities are mostly noncausal (spurious), being due to historical processes and geographical factors that shape them in similar ways. Studies of such correlations usually consider allele frequencies and linguistic groupings (dialects, languages, linguistic families or phyla), sometimes controlling for geographic, topographic, or ecological factors. Here, we consider the relation between allele frequencies and linguistic typological features. Specifically, we focus on the derived haplogroups of the brain growth and development-related genes ASPM and Microcephalin, which show signs of natural selection and a marked geographic structure, and on linguistic tone, the use of voice pitch to convey lexical or grammatical distinctions. We hypothesize that there is a relationship between the population frequency of these two alleles and the presence of linguistic tone and test this hypothesis relative to a large database (983 alleles and 26 linguistic features in 49 populations), showing that it is not due to the usual explanatory factors represented by geography and history. The relationship between genetic and linguistic diversity in this case may be causal: certain alleles can bias language acquisition or processing and thereby influence the trajectory of language change through iterated cultural transmission.

  5. Assessment of Brain-Derived Neurotrophic Gene and its Polymorphism Frequency in Patients With Bipolar Disorder in Hamadan

    Directory of Open Access Journals (Sweden)

    Ejmalian

    2016-05-01

    Full Text Available Background Bipolar disorder is a biological brain disorder which is associated with debilitating fluctuation in mood and adverse effects on patients, their families and society. The importance of genetics and its role in bipolar disorder is a controversial issue to discuss. Evidence indicates a relation between the risk of bipolar disorder and specific genes. Amongst the genes whose role has been established in bipolar disorder, the most notable gene is BDNF (Brain-derived neurotrophic factor. Methods The study is based on a case-control methodology. During 18 months, the blood samples of patients diagnosed with bipolar mood disorder who were admitted to Farshchian hospital of Hamadan from March 2011 to September 2012 and for the control group, the blood samples of patients admitted to other parts of Farshchian hospital except psychiatric ward were taken and DNA extraction from white blood cells was performed. In general, 84 patients and 85 controls were examined in this study and an expert in vials containing EDTA anticoagulant collected 4ml of blood samples. These samples were sent to the molecular biology lab of Hamadan University of Medical Science to determine their genetic polymorphisms. Genomic DNA was extracted from peripheral blood cells using the real extraction DNA kit (DNP Tm kit, Cat# DN8115C, CinnaGen co., Iran. The allele specific polymerase chain reaction technique was used to determine the frequencies of listed genotype. Considering the different variations for each gene, primers design was carried out using the Allele ID software (Allele ID 6, premier Bio soft Int, USA. For this purpose, 401 nucleotide sequences of targeted gene polymorphisms was chosen as the control sequence and desired primers for this sequence was designed and ordered (Takapouzist Co., Iran. Finally, using the mentioned method the sequences were amplified and examined on 2% agarose gel during electrophoresis. The young mania rating scale (YMRS was used to

  6. Mutation of a Gene in the Fungus Leptosphaeria maculans Allows Increased Frequency of Penetration of Stomatal Apertures of Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Candace E. Elliott; Harjono; Barbara J. Howlett

    2008-01-01

    Leptosphaeria maculans, a pathogen of Brassica napus, is unable to invade most wild-type accessions of Arabidopsis thaliana, although several mutants are susceptible. The infection pathway of L. maculans via a non-invasive inoculation method on A, thaliana Ires1 (undefined), pmr4-1 (defective in callose deposition), and pen1-1 and pen2-1 (defective in non-host responses to several pathogens) mutants is described. On wild types Col-0 and Ler-0, hyphae are generally arrested at stomatal apertures. A T-DNA insertional mutant of L. maculans (A22) that penetrates stomatal apertures of Col-0 and Ler-0 five to seven times more often than the wild-type isolate is described. The higher penetration frequency of isolate A22 is associated with an increased hypersensitive response, which includes callose deposition. Complementation analysis showed that the phenotype of this isolate is due to T-DNA insertion in an intronless gene denoted as ipa (increased penetration on Arabidopsis). This gene is predicted to encode a protein of 702 amino acids with best matches to hypothetical proteins in other filamentous ascomycetes. The ipa gene is expressed in the wild-type isolate at low levels in culture and during infection of A. thaliana and B. napus.

  7. Interferon-gamma gene polymorphism influences the frequency of a Chlamydia trachomatis cervical infection in young women.

    Science.gov (United States)

    Eleutério, José; Teles, Rosiane A; Linhares, Iara M; Normand, Neil; Witkin, Steven S

    2015-11-01

    Cervicitis associated with Chlamydia trachomatis is frequent worldwide, but the factors determining susceptibility to infection remain incompletely determined. We evaluated whether a functional single nucleotide polymorphism at position +874 in the gene coding for interferon gamma (rs2430561) influenced the likelihood of having a cervical C. trachomatis infection. This was a cross-sectional study of 142 sexually-active women attending a general gynaecology service on the outskirts of the city of Fortaleza in northeastern Brazil between August 2011 and August 2012. Endocervical swabs were evaluated for C. trachomatis DNA using hybrid capture. DNA from buccal swabs was utilised for detection of the interferon gamma 874 T/A single nucleotide polymorphism by gene amplification, endonuclease digestion and gel electrophoresis. Nineteen women (13.4%) were positive for C. trachomatis in their cervix. Positivity was 21.7% in women with the A,A genotype versus 7.0% in women with one or two T alleles (p = 0.0227). The variant T allele frequency, associated with elevated interferon gamma production, was 36.2% in women who were negative for C. trachomatis as opposed to 18.4% in women who were positive for a cervical infection with this organism (p = 0.0415). Possession of the T allele at position +874 in the gene coding for interferon gamma is associated with a reduced likelihood of a C. trachomatis cervical infection.

  8. Frequency, virulence genes and antimicrobial resistance of Listeria spp. isolated from bovine clinical mastitis.

    Science.gov (United States)

    Jamali, Hossein; Radmehr, Behrad

    2013-11-01

    The aims of this study were to determine the prevalence, characteristics and antimicrobial resistance of Listeria spp. isolated from bovine clinical mastitis in Iran. Listeria spp. were detected in 21/207 bovine mastitic milk samples from dairy farms in Iran, comprising L. monocytogenes (n=17), L. innocua (n=3) and L. ivanovii (n=1). L. monocytogenes isolates were grouped into serogroups '4b, 4d, 4e', '1/2a, 3a', '1/2b, 3b, 7' and '1/2c, 3c'; all harboured inlA, inlC and inlJ virulence genes. Listeria spp. were most frequently resistant to penicillin G (14/21 isolates, 66.7%) and tetracyclines (11/21 isolates, 52.4%).

  9. High frequencies of antibiotic resistance genes in infants’ meconium and early fecal samples

    DEFF Research Database (Denmark)

    Gosalbes, M. J.; Vallès, Y.; Jiménez-Hernández, N.

    2016-01-01

    The gastrointestinal tract (GIT) microbiota has been identified as an important reservoir of antibiotic resistance genes (ARGs) that can be horizontally transferred to pathogenic species. Maternal GIT microbes can be transmitted to the offspring, and recent work indicates that such transfer starts...... before birth. We have used culture-independent genetic screenings to explore whether ARGs are already present in the meconium accumulated in the GIT during fetal life and in feces of 1-week-old infants. We have analyzed resistance to β-lactam antibiotics (BLr) and tetracycline (Tcr), screening...... fecal samples and colostrum. Our results reveal a high prevalence of BLr and Tcr in both meconium and early fecal samples, implying that the GIT resistance reservoir starts to accumulate even before birth. We show that ARGs present in the mother may reach the meconium and colostrum and establish...

  10. Observation of radiation-specific damage in cells exposed to depleted uranium: hprt gene mutation frequency

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Alexandra C. [Science Research Departments, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)], E-mail: millera@afrri.usuhs.mil; Stewart, Michael; Rivas, Rafael [Science Research Departments, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States); Marino, Steve; Randers-Pehrson, Gerhard [Center for Radiological Research, Columbia University, 630 W. 168th St. VC11-215, New York, NY 10032 (United States); Shi Lin [Science Research Departments, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)

    2007-07-15

    Depleted uranium (DU) is a dense heavy metal used primarily in military applications. Published data from our laboratory have demonstrated that DU exposure in vitro to immortalized human osteoblast cells (HOS) is both neoplastically transforming and genotoxic. Recent animal studies have also shown that DU is leukemogenic and genotoxic. DU possesses both a radiological (alpha particle) and chemical (metal) component. Since DU has a low specific activity in comparison to natural uranium, it is not considered to be a significant radiological hazard. The potential contribution of radiation to DU-induced biological effects is unknown, and the involvement of radiation in DU-induced biological effects could have significant implications for current risk estimates for internalized DU exposure. The purpose of the current study was to measure the induction of mutagenic damage in V79 cells and to determine if radiation plays a role in the induction of that damage. Mutagenicity at the hypoxanthine (guanine) phosphoribosyltransferase (hprt) locus was measured by selection with 6-thioguanine. There was a dose-dependent increase in mutagenic response following DU exposure (10-50{mu}m); the average increase in mutagenicity above background ranged from 2.54{+-}1.19 to 8.75{+-}1.8(P<0.05). Using the same concentration (25{mu}M) of two uranyl nitrate compounds that have different uranium isotopic concentrations and, therefore, different specific activities, we examined the effect on hprt mutant frequency in vitro. V79 cells were exposed to either {sup 238}U-uranyl nitrate, specific activity 0.33{mu}Ci/g, or DU-uranyl nitrate, specific activity 0.44{mu}Ci/g, delivered at a concentration of 25{mu}M for 24 h. Results showed, that at equal uranium concentration, a 1.33-fold increase in specific activity resulted in a 1.27{+-}0.11-fold (P<0.05) increase in hprt mutant frequency. Taken together these data support earlier results showing that radiation can play a role in DU

  11. Protective Low-Frequency Variants for Preeclampsia in the Fms Related Tyrosine Kinase 1 Gene in the Finnish Population.

    Science.gov (United States)

    Lokki, A Inkeri; Daly, Emma; Triebwasser, Michael; Kurki, Mitja I; Roberson, Elisha D O; Häppölä, Paavo; Auro, Kirsi; Perola, Markus; Heinonen, Seppo; Kajantie, Eero; Kere, Juha; Kivinen, Katja; Pouta, Anneli; Salmon, Jane E; Meri, Seppo; Daly, Mark; Atkinson, John P; Laivuori, Hannele

    2017-08-01

    Preeclampsia is a common pregnancy-specific vascular disorder characterized by new-onset hypertension and proteinuria during the second half of pregnancy. Predisposition to preeclampsia is in part heritable. It is associated with an increased risk of cardiovascular disease later in life. We have sequenced 124 candidate genes implicated in preeclampsia to pinpoint genetic variants contributing to predisposition to or protection from preeclampsia. First, targeted exomic sequencing was performed in 500 preeclamptic women and 190 controls from the FINNPEC cohort (Finnish Genetics of Preeclampsia Consortium). Then 122 women with a history of preeclampsia and 1905 parous women with no such history from the National FINRISK Study (a large Finnish population survey on risk factors of chronic, noncommunicable diseases) were included in the analyses. We tested 146 rare and low-frequency variants and found an excess (observed 13 versus expected 7.3) nominally associated with preeclampsia (Ppreeclampsia. © 2017 American Heart Association, Inc.

  12. Distribution and genotype frequency of the C1431T and pro12ala polymorphisms of the peroxisome proliferator activator receptor gamma gene in an Iranian population.

    Science.gov (United States)

    Rooki, Hassan; Haerian, Monir-Sadat; Azimzadeh, Pedram; Ebrahimi, Mahmoud; Mirhafez, Reza; Ferns, Gordon; Ghayour-Mobarhan, Majid; Zali, Mohammad-Reza

    2013-10-01

    Peroxisome proliferator activator receptor gamma (PPARγ) is a nuclear transcription factor regulating multiple genes involved in cell growth, differentiation, carbohydrate and lipid metabolism and energy production. Several genetic variations in the PPARγ gene have been identified to be associated with diabetes, obesity, dyslipidemia, insulin resistance, metabolic syndrome and coronary artery disease. The present study was designed to explore the distribution of two common single nucleotide polymorphisms of the PPARγ gene (C1431T and Pro12Ala) in an Iranian population. Genotype frequencies for these two polymorphisms were compared for 160 healthy Iranian individuals with reports from other populations. The Genotyping was performed using real-time polymerase chain reaction. The genotype distribution of the C1431T PPARγ polymorphism was 0.869 for the CC genotype, 0.119 for the CT genotype and 0.013 for uncommon TT genotype. Allelic frequencies were 0.93 for C and 0.07 for T allele respectively. For the Pro12Ala polymorphism of PPARγ gene, genotypic distributions and allelic frequencies were, 0.813 for CC, 0.181 for CG and 0.06 for GG and 0.903 for C and 0.097 for G respectively. Allelic and genotypic frequencies for both polymorphisms of PPARγ gene were in Hardy-Weinberg equilibrium. Iran is a country with an ethnically diverse population and a comparison of allelic and genotypic frequencies of PPARγ C1431T and Pro12Ala polymorphisms between our population and others showed significant differences.

  13. Plasminogen Activator Inhibitor-1 (PAI-1) gene 4G/5G alleles frequency distribution in the Lebanese population.

    Science.gov (United States)

    Shammaa, Dina M R; Sabbagh, Amira S; Taher, Ali T; Zaatari, Ghazi S; Mahfouz, Rami A R

    2008-09-01

    Plasminogen activator inhibitor-1 (PAI-1) is an inhibitor of fibrinolysis. Increased plasma PAI-1 levels play an essential role in the pathogenesis of cardiovascular risk and other diseases associated with thrombosis. The 4G/5G polymorphism of the PAI-1 promoter region has been extensively studied in different populations. We studied 160 healthy unrelated Lebanese individuals using a reverse hybridization PCR assay to detect the 5G/5G, 4G/5G and, 4G/4G genotypes of the PAI-1 gene and the frequencies of the 4G and 5G alleles. We found that 4G/5G genotype was the most prevalent (45.6%) followed by 5G/5G (36.9%) and 4G/4G (17.5%). The frequencies of the 4G and 5G alleles were calculated to be 0.403 and 0.597, respectively. Compared to other ethnic communities, the Lebanese population was found to harbour a relatively high prevalence of the rare 4G allele. This, in turn, may predispose this population to develop cardiovascular diseases and other thrombotic clinical conditions. This study aids to enhance our understanding of the genetic features of the Lebanese population.

  14. DETECTION OF MENDELIAN AND GENOTYPE FREQUENCY OF GROWTH HORMONE GENE IN ONGOLE CROSSBRED CATTLE MATED BY THE ARTIFICIAL INSEMINATION TECHNIQUE

    Directory of Open Access Journals (Sweden)

    U. Paputungan

    2012-06-01

    Full Text Available The objectives of this study were to detect the Mendelian mode inheritance of growth hormone (GH and to establish genotype frequency of GH gene in Ongole-crossbred cattle mated by the artificial insemination (AI technique. Total of 76 blood samples were collected from Ongole-crossbred cows and bulls (G0, and their progenies (G1 at the Tumaratas AI service center in North Sulawesi province, Indonesia. All blood samples were screened for the presence of GH locus using a PCR-RFLP method involving restricted enzyme Msp1 on 1.2 % of agarose gel. Data were analyzed using statistical program function in Excel XP. The results showed that GH locus using alleles of Msp1+ and Msp1- enzyme restriction in Ongole-crossbred cows and bulls was inherited to their Ongole-crossbred progenies following the Mendelian mode inheritance. This Mendelian inheritance generated by AI technique was not under genetic equilibrium for the Msp1 genotype frequencies in groups of G0 and G1. The breeding program using genotypes of bulls and cows (G0 for generating the genotype of GH Msp1 enzyme restriction by AI technique should be maintained to increase these various allele dispersion rates for breeding under genetic equilibrium of the Ongole-crossbred cattle population.

  15. Total alpha-globin gene cluster deletion has high frequency in Filipinos

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, J.A.; Haruyama, A.Z.; Chu, B.M. [Kapiolani Medical Center, Honolulu, HI (United States)] [and others

    1994-09-01

    Most {alpha}-thalassemias [Thal] are due to large deletions. In Southeast Asians, the (--{sup SEA}) double {alpha}-globin gene deletion is common, 3 (--{sup Tot}) total {alpha}-globin cluster deletions are known: Filipino (--{sup Fil}), Thai (--{sup Thai}), and Chinese (--{sup Chin}). In a Hawaii Thal project, provisional diagnosis of {alpha}-Thal-1 heterozygotes was based on microcytosis, normal isoelectric focusing, and no iron deficiency. One in 10 unselected Filipinos was an {alpha}-Thal-1 heterozygote, 2/3 of these had a (--{sup Tot}) deletion: a {var_sigma}-cDNA probe consistently showed fainter intensity of the constant 5.5 kb {var_sigma}{sub 2} BamHI band, with no heterzygosity for {var_sigma}-globin region polymorphisms; {alpha}-cDNA or {var_sigma}-cDNA probes showed no BamHI or BglII bands diagnostic of the (--{sup SEA}) deletion; bands for the (-{alpha}) {alpha}-Thal-2 single {alpha}-globin deletions were only seen in Hb H cases. A reliable monoclonal anti-{var_sigma}-peptide antibody test for the (--{sup SEA}) deletion was always negative in (--{sup Tot}) samples. Southern digests with the Lo probe, a gift from D. Higgs of Oxford Univ., confirmed that 49 of 50 (--{sup Tot}) chromosomes in Filipinos were (--{sup Fil}). Of 20 {alpha}-Thal-1 hydrops born to Filipinos, 11 were (--{sup Fil}/--{sup SEA}) compound heterozygotes; 9 were (--{sup SEA}/--{sup SEA}) homozygotes, but none was a (--{sup Fil}/--{sup Fil}).

  16. A Population Based Study of the Genetic Association between Catecholamine Gene Variants and Spontaneous Low-Frequency Fluctuations in Reaction Time.

    Directory of Open Access Journals (Sweden)

    Jojanneke A Bastiaansen

    Full Text Available The catecholamines dopamine and noradrenaline have been implicated in spontaneous low-frequency fluctuations in reaction time, which are associated with attention deficit hyperactivity disorder (ADHD and subclinical attentional problems. The molecular genetic substrates of these behavioral phenotypes, which reflect frequency ranges of intrinsic neuronal oscillations (Slow-4: 0.027-0.073 Hz; Slow-5: 0.010-0.027 Hz, have not yet been investigated. In this study, we performed regression analyses with an additive model to examine associations between low-frequency fluctuations in reaction time during a sustained attention task and genetic markers across 23 autosomal catecholamine genes in a large young adult population cohort (n = 964, which yielded greater than 80% power to detect a small effect size (f(2 = 0.02 and 100% power to detect a small/medium effect size (f(2 = 0.15. At significance levels corrected for multiple comparisons, none of the gene variants were associated with the magnitude of low-frequency fluctuations. Given the study's strong statistical power and dense coverage of the catecholamine genes, this either indicates that associations between low-frequency fluctuation measures and catecholamine gene variants are absent or that they are of very small effect size. Nominally significant associations were observed between variations in the alpha-2A adrenergic receptor gene (ADRA2A and the Slow-5 band. This is in line with previous reports of an association between ADRA2A gene variants and general reaction time variability during response selection tasks, but the specific association of these gene variants and low-frequency fluctuations requires further confirmation. Pharmacological challenge studies could in the future provide convergent evidence for the noradrenergic modulation of both general and time sensitive measures of intra-individual variability in reaction time.

  17. Allele and genotype frequency of a genetic variant in ataxia telangiectasia mutated gene affecting glycemic response to metformin in South Indian population

    Directory of Open Access Journals (Sweden)

    Saranya Vilvanathan

    2014-01-01

    Full Text Available Allele and genotype frequency of a genetic variant in ATM gene affecting glycemic response to metformin in South Indian population . Context: The novel polymorphism in ATM gene (rs11212617, which is implicated to have association with metformin response, exhibits inter-ethnic variability in the allele and genotype frequency distribution . Aims and Design: The objective of the present study is to establish the allele and genotype frequency of rs11212617 single nucleotide polymorphism in ATM gene, in South Indian population and to find if this variant has any role in the etiology of type 2 diabetes mellitus . Materials and Methods: The study was performed in 2 cohorts of populations, 112 healthy volunteers and 118 type 2 diabetes mellitus patients. Genomic deoxyribonucleic acid (DNA was extracted from peripheral blood leucocytes by phenol-chloroform method and genotyping was performed by real-time polymerase chain reaction using TaqMan assay. Results: In South Indian population, the frequency of major A allele was 0.65 and the minor C allele was 0.35. AA and CC are the homozygous genotypes with frequency of 0.39 and 0.09 respectively. The frequency of heterozygous genotype AC (0.52 was found to be higher than the homozygotes. There was no significant difference in the frequency distribution in the diabetic population, which implies that this variant does not have any causative role in the disease etiology. The frequency distributions were found to be significantly different from the distributions in other ethnic populations such as Caucasians, Chinese, Japanese and Africans. But there was no significant difference when compared with the Gujarati Indians of Houston. Conclusion: The frequency distribution of this novel variant in South Indian population forms a framework for further gene disease association studies to establish the association of this variant with metformin response. Our study could not find any association of this variant with

  18. High-frequency stimulation induces gradual immediate early gene expression in maturing adult-generated hippocampal granule cells.

    Science.gov (United States)

    Jungenitz, Tassilo; Radic, Tijana; Jedlicka, Peter; Schwarzacher, Stephan W

    2014-07-01

    Increasing evidence shows that adult neurogenesis of hippocampal granule cells is advantageous for learning and memory. We examined at which stage of structural maturation and age new granule cells can be activated by strong synaptic stimulation. High-frequency stimulation of the perforant pathway in urethane-anesthetized rats elicited expression of the immediate early genes c-fos, Arc, zif268 and pCREB133 in almost 100% of mature, calbindin-positive granule cells. In contrast, it failed to induce immediate early gene expression in immature doublecortin-positive granule cells. Furthermore, doublecortin-positive neurons did not react with c-fos or Arc expression to mild theta-burst stimulation or novel environment exposure. Endogenous expression of pCREB133 was increasingly present in young cells with more elaborated dendrites, revealing a close correlation to structural maturation. Labeling with bromodeoxyuridine revealed cell age dependence of stimulation-induced c-fos, Arc and zif268 expression, with only a few cells reacting at 21 days, but with up to 75% of cells activated at 35-77 days of cell age. Our results indicate an increasing synaptic integration of maturing granule cells, starting at 21 days of cell age, but suggest a lack of ability to respond to activation with synaptic potentiation on the transcriptional level as long as immature cells express doublecortin. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. In silico analysis highlights the frequency and diversity of type 1 lantibiotic gene clusters in genome sequenced bacteria

    LENUS (Irish Health Repository)

    Marsh, Alan J

    2010-11-30

    Abstract Background Lantibiotics are lanthionine-containing, post-translationally modified antimicrobial peptides. These peptides have significant, but largely untapped, potential as preservatives and chemotherapeutic agents. Type 1 lantibiotics are those in which lanthionine residues are introduced into the structural peptide (LanA) through the activity of separate lanthionine dehydratase (LanB) and lanthionine synthetase (LanC) enzymes. Here we take advantage of the conserved nature of LanC enzymes to devise an in silico approach to identify potential lantibiotic-encoding gene clusters in genome sequenced bacteria. Results In total 49 novel type 1 lantibiotic clusters were identified which unexpectedly were associated with species, genera and even phyla of bacteria which have not previously been associated with lantibiotic production. Conclusions Multiple type 1 lantibiotic gene clusters were identified at a frequency that suggests that these antimicrobials are much more widespread than previously thought. These clusters represent a rich repository which can yield a large number of valuable novel antimicrobials and biosynthetic enzymes.

  20. GJB2 and mitochondrial A1555G gene mutations in nonsyndromic profound hearing loss and carrier frequencies in healthy individuals

    Indian Academy of Sciences (India)

    Elif Baysal; Yildirim A. Bayazit; Serdar Ceylaner; Necat Alatas; Buket Donmez; Gulay Ceylaner; Imran San; Baki Korkmaz; Akin Yilmaz; Adnan Menevse; Senay Altunyay; Bulent Gunduz; Nebil Goksu; Ahmet Arslan; Abdullah Ekmekci

    2008-04-01

    This study aimed to assess mutations in GJB2 gene (connexin 26), as well as A1555G mitochondrial mutation in both the patients with profound genetic nonsyndromic hearing loss and healthy controls. Ninety-five patients with profound hearing loss (>90 dB) and 67 healthy controls were included. All patients had genetic nonsyndromic hearing loss. Molecular analyses were performed for connexin 26 (35delG, M34T, L90P, R184P, delE120, 167delT, 235delC and IVS1+1 A → G) mutations, and for mitochondrial A1555G mutation. Twenty-two connexin 26 mutations were found in 14.7% of the patients, which were 35delG, R184P, del120E and IVS1+1 A → G. Mitochondrial A1555G mutation was not encountered. The most common GJB2 gene mutation was 35delG, which was followed by del120E, IVS1+1 A → G and R184P, and 14.3% of the patients segregated with DFNB1. In consanguineous marriages, the most common mutation was 35delG. The carrier frequency for 35delG mutation was 1.4% in the controls. 35delG and del120E populations, seems the most common connexin 26 mutations that cause genetic nonsyndromic hearing loss in this country. Nonsyndromic hearing loss mostly shows DFNB1 form of segregation.

  1. Mutation frequencies of X-linked mental retardation genes in families from the EuroMRX consortium.

    Science.gov (United States)

    de Brouwer, Arjan P M; Yntema, Helger G; Kleefstra, Tjitske; Lugtenberg, Dorien; Oudakker, Astrid R; de Vries, Bert B A; van Bokhoven, Hans; Van Esch, Hilde; Frints, Suzanne G M; Froyen, Guy; Fryns, Jean-Pierre; Raynaud, Martine; Moizard, Marie-Pierre; Ronce, Nathalie; Bensalem, Anissa; Moraine, Claude; Poirier, Karine; Castelnau, Laetitia; Saillour, Yoann; Bienvenu, Thierry; Beldjord, Chérif; des Portes, Vincent; Chelly, Jamel; Turner, Gillian; Fullston, Tod; Gecz, Jozef; Kuss, Andreas W; Tzschach, Andreas; Jensen, Lars Riff; Lenzner, Steffen; Kalscheuer, Vera M; Ropers, Hans-Hilger; Hamel, Ben C J

    2007-02-01

    The EuroMRX family cohort consists of about 400 families with non-syndromic and 200 families with syndromic X-linked mental retardation (XLMR). After exclusion of Fragile X (Fra X) syndrome, probands from these families were tested for mutations in the coding sequence of 90 known and candidate XLMR genes. In total, 73 causative mutations were identified in 21 genes. For 42% of the families with obligate female carriers, the mental retardation phenotype could be explained by a mutation. There was no difference between families with (lod score >2) or without (lod score <2) significant linkage to the X chromosome. For families with two to five affected brothers (brother pair=BP families) only 17% of the MR could be explained. This is significantly lower (P=0.0067) than in families with obligate carrier females and indicates that the MR in about 40% (17/42) of the BP families is due to a single genetic defect on the X chromosome. The mutation frequency of XLMR genes in BP families is lower than can be expected on basis of the male to female ratio of patients with MR or observed recurrence risks. This might be explained by genetic risk factors on the X chromosome, resulting in a more complex etiology in a substantial portion of XLMR patients. The EuroMRX effort is the first attempt to unravel the molecular basis of cognitive dysfunction by large-scale approaches in a large patient cohort. Our results show that it is now possible to identify 42% of the genetic defects in non-syndromic and syndromic XLMR families with obligate female carriers.

  2. Molecular genetics of X chromosome-linked color vision among populations of African and Japanese ancestry: High frequency of a shortened red pigment gene among Afro-Americans

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, A.L.; Deeb, S.S.; Motulsky, A.G. (Univ. of Washington, Seattle (USA))

    1990-09-01

    Red-green color vision in humans is mediated by the X chromosome-linked highly homologous red and green pigment genes. Color vision defects are caused by deletions and fusions involving these genes. However, the authors found the frequency of molecular abnormalities among Caucasians to be twice as high as that of phenotypic color vision defects. Among Japanese the frequency of phenotypic and molecular color vision defects was similar. Among Afro-Americans, molecular defects were at least five times more frequent than phenotypic color vision defects. In addition, 35% of Afro-Americans, 2% of Japanese, and <1% of Caucasians had a shortened red pigment gene not associated with phenotpyic color vision defects. This gene lacked 1.9 kilobases in its first intron and had the identical size as the green pigment gene from which it presumably originated by gene conversion in an ancestral African population. This gene and the closely linked glucose-6-phosphate dehydrogenase A{sup +} variant were in linkage equilibrium. A model for the evolutionary origin of the color vision pigment genes in higher primates is portrayed.

  3. Adamantane-Resistant Influenza A Viruses in the World (1902–2013): Frequency and Distribution of M2 Gene Mutations

    Science.gov (United States)

    Dong, Guoying; Peng, Chao; Luo, Jing; Wang, Chengmin; Han, Le; Wu, Bin; Ji, Guangju; He, Hongxuan

    2015-01-01

    Adamantanes (amantadine and rimantadine) have been used to prevent and treat influenza A virus infections for many years; however, resistance to these drugs has been widely reported in the world. To investigate the frequency and distribution of M2 gene mutations in adamantane-resistant influenza variants circulated in the world between 1902 and 2013, 31251 available M2 protein sequences from different HA-subtype influenza A viruses (H1–H17) were analyzed and adamantane resistance-associated mutations were compared (L26F, V27A, A30T, A30V, S31N, G34E, and L38F). We find that 45.2% (n = 14132) of influenza A (H1–H17) viruses circulating globally were resistant to adamantanes, and the vast majority of resistant viruses (95%) bear S31N mutations. Whereas, only about 1% have V27A mutations and other mutations (L26F, A30T, G34E, and L38F) were extremely rare (their prevalence appeared to be resistance to adamantanes. In contrast, the appearance of adamantane-resistant mutants in H2, H4, H6, H10, and H11 subtypes was rare. However, no adamantane resistance viruses were identified among other HA subtypes (H8, H12–H16). Our findings indicate that the frequency and distribution of adamantane-resistant influenza variants varied among different HA subtypes, host species, years of isolation, and geographical areas. This comprehensive study raises concerns about the increasing prevalence of adamantane-resistant influenza A viruses and highlights the importance of monitoring the emergence and worldwide spread of adamantane-resistant variants. PMID:25768797

  4. Frequency- and state-dependent blockade of human ether-a-go-go-related gene K+ channel by arecoline hydrobromide.

    Science.gov (United States)

    Zhao, Xu-yan; Liu, Yu-qi; Fu, Yi-cheng; Xu, Bin; Gao, Jin-liao; Zheng, Xiao-qin; Lin, Min; Chen, Mei-yan; Li, Yang

    2012-03-01

    The rapidly activating delayed rectifier potassium current (I(Kr)), whose pore-forming alpha subunit is encoded by the human ether-a-go-go-related gene (hERG), is a key contributor to the third phase of action potential repolarization. The aim of this study was to investigate the effect and mechanism of arecoline hydrobromide induced inhibition of hERG K(+) current (I(hERG)). Transient transfection of hERG channel cDNA plasmid pcDNA3.1 into the cultured HEK293 cells was performed using Lipofectamine. A standard whole-cell patch-clamp technique was used to record the I(hERG) before and after the exposure to arecoline. Arecoline decreased the amplitude and the density of the I(hERG) in a concentration-dependent manner (IC(50) = 9.55 mmol/L). At test potential of +60 mV, the magnitude of I(hERG) tail at test pulse of -40 mV was reduced from (151.7 ± 6.2) pA/pF to (84.4 ± 7.6) pA/pF (P arecoline in the open and inactivated state was significant in a state-dependent manner. The maximal blockade was achieved in the inactivated state. Studies of gating mechanism showed that the steady-state activation curve of I(hERG) was significantly negatively shifted by arecoline. Time constants of activation were shortened. Steady-state inactivation curve and time constants of fast inactivation were not significantly affected by arecoline. Furthermore, the inhibition of I(hERG) by arecoline was characterized markedly by a frequency-dependent manner from 0.03 to 1.00 Hz pulse. Arecoline could potently block I(hERG) in both frequency and state-dependent manner.

  5. Molecular spectrum of KRAS, BRAF, and PIK3CA gene mutation: determination of frequency, distribution pattern in Indian colorectal carcinoma.

    Science.gov (United States)

    Bisht, Swati; Ahmad, Firoz; Sawaimoon, Satyakam; Bhatia, Simi; Das, Bibhu Ranjan

    2014-09-01

    Molecular evaluation of KRAS, BRAF, and PIK3CA mutation has become an important part in colorectal carcinoma evaluation, and their alterations may determine the therapeutic response to anti-EGFR therapy. The current study demonstrates the evaluation of KRAS, BRAF, and PIK3CA mutation using direct sequencing in 204 samples. The frequency of KRAS, BRAF, and PIK3CA mutations was 23.5, 9.8, and 5.9 %, respectively. Five different substitution mutations at KRAS codon 12 (G12S, G12D, G12A, G12V, and G12C) and one substitution type at codon 13 (G13D) were observed. KRAS mutations were significantly higher in patients who were >50 years, and were associated with moderate/poorly differentiated tumors and adenocarcinomas. All mutations in BRAF gene were of V600E type, which were frequent in patients who were ≤ 50 years. Unlike KRAS mutations, BRAF mutations were more frequent in well-differentiated tumors and right-sided tumors. PIK3CA-E545K was the most recurrent mutation while other mutations detected were T544I, Q546R, H1047R, G1049S, and D1056N. No significant association of PIK3CA mutation with age, tumor differentiation, location, and other parameters was noted. No concomitant mutation of KRAS and BRAF mutations was observed, while, interestingly, five cases showed concurrent mutation of KRAS and PIK3CA mutations. In conclusion, to our knowledge, this is the first study to evaluate the PIK3CA mutation in Indian CRC patients. The frequency of KRAS, BRAF, and PIK3CA was similar to worldwide reports. Furthermore, identification of molecular markers has unique strengths, and can provide insights into the pathogenic process and help optimize personalized prevention and therapy.

  6. Triglyceride associated polymorphisms of the APOA5 gene have very different allele frequencies in Pune, India compared to Europeans

    Directory of Open Access Journals (Sweden)

    Chandak Giriraj R

    2006-10-01

    Full Text Available Abstract Background The APOA5 gene variants, -1131T>C and S19W, are associated with altered triglyceride concentrations in studies of subjects of Caucasian and East Asian descent. There are few studies of these variants in South Asians. We investigated whether the two APOA5 variants also show similar association with various lipid parameters in Indian population as in the UK white subjects. Methods We genotyped 557 Indian adults from Pune, India, and 237 UK white adults for -1131T>C and S19W variants in the APOA5 gene, compared their allelic and genotype frequency and determined their association with fasting serum triglycerides, total cholesterol, HDL and LDL cholesterol levels using univariate general linear analysis. APOC3 SstI polymorphism was also analyzed in 175 Pune Indian subjects for analysis of linkage disequilibrium with the APOA5 variants. Results The APOA5 -1131C allele was more prevalent in Indians from Pune (Pune Indians compared to UK white subjects (allele frequency 20% vs. 4%, p = 0.00001, whereas the 19W allele was less prevalent (3% vs. 6% p = 0.0015. Patterns of linkage disequilibrium between the two variants were similar between the two populations and confirmed that they occur on two different haplotypes. In Pune Indians, the presence of -1131C allele and the 19W allele was associated with a 19% and 15% increase respectively in triglyceride concentrations although only -1131C was significant (p = 0.0003. This effect size was similar to that seen in the UK white subjects. Analysis of the APOC3 SstI polymorphism in 175 Pune Indian subjects showed that this variant is not in appreciable linkage disequilibrium with the APOA5 -1131T>C variant (r2 = 0.07. Conclusion This is the first study to look at the role of APOA5 in Asian Indian subjects that reside in India. The -1131C allele is more prevalent and the 19W allele is less prevalent in Pune Indians compared to UK Caucasians. We confirm that the APOA5 variants are associated

  7. Frequency of 677C -> T and 1298A -> C polymorphisms in the 5,10-methylenetetrahydrofolate reductase (MTHFR gene in Turner syndrome individuals

    Directory of Open Access Journals (Sweden)

    Kelly Santos

    2006-01-01

    Full Text Available Turner syndrome (TS is an interesting model for investigating the association between methylenetetrahydrofolate reductase (MTHFR gene polymorphisms and non-disjunction because of the high frequency of chromosomal mosaicism among patients with this syndrome. We determined the frequencies of MTHFR 677C -> T and 1298A -> C polymorphic mutations in 49 patients with TS and 200 control individuals. The frequency of the 677C -> T allele was 0.39 for patients and 0.29 for controls while that of the 1298A -> C allele was 0.28 for patients and 0.25 for controls. Genotype frequencies were shown to be different in patients and controls (chi2 = 12.143; p = 0.033, and this was attributable to the higher frequency of the C677C -> T /677C -> T genotype among TS patients. In homozygotes, this mutation might have an effect on somatic chromosome disjunction by decreasing MTHFR activity.

  8. Extremely low-frequency electromagnetic fields affect transcript levels of neuronal differentiation-related genes in embryonic neural stem cells.

    Directory of Open Access Journals (Sweden)

    Qinlong Ma

    Full Text Available Previous studies have reported that extremely low-frequency electromagnetic fields (ELF-EMF can affect the processes of brain development, but the underlying mechanism is largely unknown. The proliferation and differentiation of embryonic neural stem cells (eNSCs is essential for brain development during the gestation period. To date, there is no report about the effects of ELF-EMF on eNSCs. In this paper, we studied the effects of ELF-EMF on the proliferation and differentiation of eNSCs. Primary cultured eNSCs were treated with 50 Hz ELF-EMF; various magnetic intensities and exposure times were applied. Our data showed that there was no significant change in cell proliferation, which was evaluated by cell viability (CCK-8 assay, DNA synthesis (Edu incorporation, average diameter of neurospheres, cell cycle distribution (flow cytometry and transcript levels of cell cycle related genes (P53, P21 and GADD45 detected by real-time PCR. When eNSCs were induced to differentiation, real-time PCR results showed a down-regulation of Sox2 and up-regulation of Math1, Math3, Ngn1 and Tuj1 mRNA levels after 50 Hz ELF-EMF exposure (2 mT for 3 days, but the percentages of neurons (Tuj1 positive cells and astrocytes (GFAP positive cells were not altered when detected by immunofluorescence assay. Although cell proliferation and the percentages of neurons and astrocytes differentiated from eNSCs were not affected by 50 Hz ELF-EMF, the expression of genes regulating neuronal differentiation was altered. In conclusion, our results support that 50 Hz ELF-EMF induce molecular changes during eNSCs differentiation, which might be compensated by post-transcriptional mechanisms to support cellular homeostasis.

  9. Low frequency pulsed electromagnetic field affects proliferation, tissue-specific gene expression, and cytokines release of human tendon cells.

    Science.gov (United States)

    de Girolamo, L; Stanco, D; Galliera, E; Viganò, M; Colombini, A; Setti, S; Vianello, E; Corsi Romanelli, M M; Sansone, V

    2013-07-01

    Low frequency pulsed electromagnetic field (PEMF) has proven to be effective in the modulation of bone and cartilage tissue functional responsiveness, but its effect on tendon tissue and tendon cells (TCs) is still underinvestigated. PEMF treatment (1.5 mT, 75 Hz) was assessed on primary TCs, harvested from semitendinosus and gracilis tendons of eight patients, under different experimental conditions (4, 8, 12 h). Quantitative PCR analyses were conducted to identify the possible effect of PEMF on tendon-specific gene transcription (scleraxis, SCX and type I collagen, COL1A1); the release of pro- and anti-inflammatory cytokines and of vascular endothelial growth factor (VEGF) was also assessed. Our findings show that PEMF exposure is not cytotoxic and is able to stimulate TCs' proliferation. The increase of SCX and COL1A1 in PEMF-treated cells was positively correlated to the treatment length. The release of anti-inflammatory cytokines in TCs treated with PEMF for 8 and 12 h was significantly higher in comparison with untreated cells, while the production of pro-inflammatory cytokines was not affected. A dramatically higher increase of VEGF-A mRNA transcription and of its related protein was observed after PEMF exposure. Our data demonstrated that PEMF positively influence, in a dose-dependent manner, the proliferation, tendon-specific marker expression, and release of anti-inflammatory cytokines and angiogenic factor in a healthy human TCs culture model.

  10. Frequency of Thrombophilic Gene Mutations in Patients with Deep Vein Thrombosis and in Women with Recurrent Pregnancy Loss

    Directory of Open Access Journals (Sweden)

    Elgari Mahmoud Mohamed

    2017-05-01

    Full Text Available Thrombophilia may be anticipated by single or combined hereditary defects in encoding genes factor V, Prothrombin, and MTHFR. The aim of this study was to determine the prevalence and associated risks of V Leiden (G1691A, Prothrombin (G20210A, and MTHFR (C677T mutations in Saudi women with Deep Vein Thrombosis (DVT and women with recurrent pregnancy loss (RPL. Protein C and protein S activity were measured to determine combined effects, if any. We examined 60 women with a history of DVT and 60 with RPL, extracted DNA from EDTA blood and determined three mutations by using multiplex PCR reactions followed by Strip Assay KIT. Pro C Global assay was used to determine the cutoff value [PCATNR = 0.80]. Protein C/S chromogenic assay was used to estimate protein C and S percentages. Frequency of Factor V Leiden G/A genotype in patients with DVT 7 (11.6% had a significant association for DVT χ2 (OR = 5.1, P = 0.03. In women with RPL the three mutations did not show any significant association, levels of Protein C, protein S and PCAT-NR in patient groups not different from controls (P > 0.05. In conclusion, we recommend expanding on these data to provide larger-scale studies.

  11. The Relative Contribution of Genes and Environment to Alcohol Use in Early Adolescents : Are Similar Factors Related to Initiation of Alcohol Use and Frequency of Drinking?

    NARCIS (Netherlands)

    Poelen, E.A.P.; Derks, E.M.; Engels, R.C.M.E.; Scholte, R.H.J.; Willemsen, A.H.M.; Boomsma, D.I.

    2008-01-01

    Background: The present study assessed the relative contribution of genes and environment to individual differences in initiation of alcohol use and frequency of drinking among early adolescents and examined the extent to which the same genetic and environmental factors influence both individual dif

  12. Low frequency of the scrapile resistance-associated allele and presence of lysine-171 allele of the prion protein gene in Italian Biellese ovine breed

    NARCIS (Netherlands)

    Acutis, P.L.; Sbaiz, L.; Verburg, F.J.; Riina, M.V.; Ru, G.; Moda, G.; Caramelli, M.; Bossers, A.

    2004-01-01

    Frequencies of polymorphisms at codons 136, 154 and 171 of the prion protein (PrP) gene were studied in 1207 pure-bred and cross-bred Italian Biellese rams, a small ovine breed of about 65 000 head in Italy. Aside from the five most common alleles (VRQ, ARQ, ARR, AHQ and ARH), the rare ARK allele wa

  13. Low frequency of the scrapile resistance-associated allele and presence of lysine-171 allele of the prion protein gene in Italian Biellese ovine breed

    NARCIS (Netherlands)

    Acutis, P.L.; Sbaiz, L.; Verburg, F.J.; Riina, M.V.; Ru, G.; Moda, G.; Caramelli, M.; Bossers, A.

    2004-01-01

    Frequencies of polymorphisms at codons 136, 154 and 171 of the prion protein (PrP) gene were studied in 1207 pure-bred and cross-bred Italian Biellese rams, a small ovine breed of about 65 000 head in Italy. Aside from the five most common alleles (VRQ, ARQ, ARR, AHQ and ARH), the rare ARK allele

  14. The position of DNA cleavage by TALENs and cell synchronization influences the frequency of gene editing directed by single-stranded oligonucleotides.

    Directory of Open Access Journals (Sweden)

    Natalia Rivera-Torres

    Full Text Available With recent technological advances that enable DNA cleavage at specific sites in the human genome, it may now be possible to reverse inborn errors, thereby correcting a mutation, at levels that could have an impact in a clinical setting. We have been developing gene editing, using single-stranded DNA oligonucleotides (ssODNs, as a tool to direct site specific single base changes. Successful application of this technique has been demonstrated in many systems ranging from bacteria to human (ES and somatic cells. While the frequency of gene editing can vary widely, it is often at a level that does not enable clinical application. As such, a number of stimulatory factors such as double-stranded breaks are known to elevate the frequency significantly. The majority of these results have been discovered using a validated HCT116 mammalian cell model system where credible genetic and biochemical readouts are available. Here, we couple TAL-Effector Nucleases (TALENs that execute specific ds DNA breaks with ssODNs, designed specifically to repair a missense mutation, in an integrated single copy eGFP gene. We find that proximal cleavage, relative to the mutant base, is key for enabling high frequencies of editing. A directionality of correction is also observed with TALEN activity upstream from the target base being more effective in promoting gene editing than activity downstream. We also find that cells progressing through S phase are more amenable to combinatorial gene editing activity. Thus, we identify novel aspects of gene editing that will help in the design of more effective protocols for genome modification and gene therapy in natural genes.

  15. [The CYP1B1 and CYP2F1 genes polymorphisms frequency in three ethnic groups of Bashkortostan and chronic obstructive pulmonary disease patients].

    Science.gov (United States)

    Korytina, G F; Akhmadishina, L Z; Viktorova, T V

    2010-01-01

    Chronic obstructive pulmonary disease is a multifactorial respiratory disorder. Members of the cytochrome P450 family catalyze the oxidative metabolism of exogenous chemicals and activate their substrates into reactive intermediates that may initiate lung injury. The aim of this study was to learn interethnic variation in frequency distribution patterns of CYP1B1 and CYP2F1 genes polymorphic markers and to analyse its association withchronic obstructive pulmonary disease. The polymorphic markers Leu432Val(CYP1B1) and c.14_15insC(CYP2F1) were studied at chronic obstructive pulmonary disease patients (Russian (N=169), Tatar (N=137)) and cases of healthy individuals (Russian (N=191), Tatar (N=198) and Bashkir (N=78)), residents of Bashkortostan by PCR-RFLP method. It was shown that the CYP2F1 gene genotype frequency distribution patterns differed between three ethnic groups (chi2 = 21.29, df=4, P = 0.0001), because of high frequency of c.14_15insC/c.14_15insC genotype in Tatars (6.38%). On the other hand, high frequency (39.74%) of normal/ c.14_15insC genotype was appeared in Bashkirs. Association analysis of CYP2F1 geneinsertion variant with chronic obstructive pulmonary disease have shown high frequency (87.5%) of normal allele in Tatars patients with very severe stage and manifestation of chronic obstructive pulmonary disease after 55 years (chi2 = 3.964, df=1, P = 0.046; OR = = 2.268). It was shown that allele and genotype frequency distribution of Leu432ValCYP1B1 gene not differed between Russian, Tatar and Bashkir ethnic groups. We did not find any association of Leu432Val CYP1B1 gene with chronic obstructive pulmonary disease.

  16. Low frequency of CD4+CD25+ Treg in SLE patients: a heritable trait associated with CTLA4 and TGFβ gene variants

    Directory of Open Access Journals (Sweden)

    Viana João F

    2009-01-01

    Full Text Available Abstract Background CD4+CD25+ regulatory T cells play an essential role in maintaining immune homeostasis and preventing autoimmunity. Therefore, defects in Treg development, maintenance or function have been associated with several human autoimmune diseases including Systemic Lupus Erythematosus (SLE, a systemic autoimmune disease characterized by loss of tolerance to nuclear components and significantly more frequent in females. Results To investigate the involvement of Treg in SLE pathogenesis, we determined the frequency of CD4+CD25+CD45RO+ T cells, which encompass the majority of Treg activity, in the PBMC of 148 SLE patients (76 patients were part of 54 families, 166 relatives and 117 controls. SLE patients and their relatives were recruited in several Portuguese hospitals and through the Portuguese Lupus Association. Control individuals were blood donors recruited from several regional blood donor centers. Treg frequency was significantly lower in SLE patients than healthy controls (z = -6.161, P P bona fide FOXP3+CD4+CD25+ Treg. Treg frequency was negatively correlated with SLE activity index (SLEDAI and titers of serum anti-dsDNA antibodies. Both Treg frequency and disease activity were modulated by IVIg treatment in a documented SLE case. The segregation of Treg frequency within the SLE families was indicative of a genetic trait. Candidate gene analysis revealed that specific variants of CTLA4 and TGFβ were associated with the decreased frequency of Treg in PBMC, while FOXP3 gene variants were associated with affection status, but not with Treg frequency. Conclusion SLE patients have impaired Treg production or maintenance, a trait strongly associated with SLE disease activity and autoantibody titers, and possibly resulting from the inability to convert FOXP3+CD25- into FOXP3+CD25+ T cells. Treg frequency is highly heritable within SLE families, with specific variants of the CTLA4 and TGFβ genes contributing to this trait, while FOXP

  17. Frequency of rs731236 (Taql), rs2228570 (Fok1) of Vitamin-D Receptor (VDR) gene in Emirati healthy population.

    Science.gov (United States)

    Osman, Enas; Al Anouti, Fatme; El Ghazali, Gehad; Haq, Afrozul; Mirgani, Rajaa; Al Safar, Habiba

    2015-12-01

    Vitamin D is getting more attention everyday due to its importance in maintaining bone and calcium homeostasis, cellular proliferation, differentiation and immune response. Vitamin D is derived from diet or elicited in the skin by the activation of 7-dehydrocholesterol, which is an inert molecule that must be activated by ultraviolet light to form pre-vitamin D3. Recent studies connected the gene encoding for vitamin D (VDR) to the genetic control of bone mass and other diseases. As VDR SNPs have been associated with several disorders and diseases, it's important to investigate the allelic and genotypic distribution among populations. The aim of this study is to determine the frequency of rs731236 (Taq1) and rs2228570 (Fok1) variants in healthy Emirati individuals and compare their genotype and allele distribution with other populations. In this study 282 (female, 187; male, 95) unrelated healthy UAE nationals were involved. Two hundreds and eight two DNA samples been collected to genotype rs731236 (Taq1) and rs2228570 (Fok1) VDR SNPs. Our results indicate that the distribution of the alleles and genotypes of rs731236 (Taq1) and rs2228570 (Fok1) vary considerably in different populations. In the Emirati population the distribution of rs731236 (Taq1) and rs2228570 (Fok1) were AA 38%, AG 42%, GG 20% and AA 27%, AG 42%, GG 31% respectively. The Emirati population genotype and allele distribution of rs731236 (Taq1) and rs2228570 (Fok1) had no difference with Caucasians from USA and France. However, there was significant difference with Asian populations.

  18. High frequency of additional gene mutations in acute myeloid leukemia with MLL partial tandem duplication: DNMT3A mutation is associated with poor prognosis.

    Science.gov (United States)

    Kao, Hsiao-Wen; Liang, D Cherng; Kuo, Ming-Chung; Wu, Jin-Hou; Dunn, Po; Wang, Po-Nan; Lin, Tung-Liang; Shih, Yu-Shu; Liang, Sung-Tzu; Lin, Tung-Huei; Lai, Chen-Yu; Lin, Chun-Hui; Shih, Lee-Yung

    2015-10-20

    The mutational profiles of acute myeloid leukemia (AML) with partial tandem duplication of mixed-lineage leukemia gene (MLL-PTD) have not been comprehensively studied. We studied 19 gene mutations for 98 patients with MLL-PTD AML to determine the mutation frequency and clinical correlations. MLL-PTD was screened by reverse-transcriptase PCR and confirmed by real-time quantitative PCR. The mutational analyses were performed with PCR-based assays followed by direct sequencing. Gene mutations of signaling pathways occurred in 63.3% of patients, with FLT3-ITD (44.9%) and FLT3-TKD (13.3%) being the most frequent. 66% of patients had gene mutations involving epigenetic regulation, and DNMT3A (32.7%), IDH2 (18.4%), TET2 (18.4%), and IDH1 (10.2%) mutations were most common. Genes of transcription pathways and tumor suppressors accounted for 23.5% and 10.2% of patients. RUNX1 mutation occurred in 23.5% of patients, while none had NPM1 or double CEBPA mutation. 90.8% of MLL-PTD AML patients had at least one additional gene mutation. Of 55 MLL-PTD AML patients who received standard chemotherapy, age older than 50 years and DNMT3A mutation were associated with inferior outcome. In conclusion, gene mutations involving DNA methylation and activated signaling pathway were common co-existed gene mutations. DNMT3A mutation was a poor prognostic factor in MLL-PTD AML.

  19. Rainfall-driven sex-ratio genes in African buffalo suggested by correlations between Y-chromosomal haplotype frequencies and foetal sex ratio

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    Greyling Barend J

    2010-04-01

    Full Text Available Abstract Background The Y-chromosomal diversity in the African buffalo (Syncerus caffer population of Kruger National Park (KNP is characterized by rainfall-driven haplotype frequency shifts between year cohorts. Stable Y-chromosomal polymorphism is difficult to reconcile with haplotype frequency variations without assuming frequency-dependent selection or specific interactions in the population dynamics of X- and Y-chromosomal genes, since otherwise the fittest haplotype would inevitably sweep to fixation. Stable Y-chromosomal polymorphism due one of these factors only seems possible when there are Y-chromosomal distorters of an equal sex ratio, which act by negatively affecting X-gametes, or Y-chromosomal suppressors of a female-biased sex ratio. These sex-ratio (SR genes modify (suppress gamete transmission in their own favour at a fitness cost, allowing for stable polymorphism. Results Here we show temporal correlations between Y-chromosomal haplotype frequencies and foetal sex ratios in the KNP buffalo population, suggesting SR genes. Frequencies varied by a factor of five; too high to be alternatively explained by Y-chromosomal effects on pregnancy loss. Sex ratios were male-biased during wet and female-biased during dry periods (male proportion: 0.47-0.53, seasonally and annually. Both wet and dry periods were associated with a specific haplotype indicating a SR distorter and SR suppressor, respectively. Conclusions The distinctive properties suggested for explaining Y-chromosomal polymorphism in African buffalo may not be restricted to this species alone. SR genes may play a broader and largely overlooked role in mammalian sex-ratio variation.

  20. Asian population frequencies and haplotype distribution of killer cell immunoglobulin-like receptor (KIR) genes among Chinese, Malay, and Indian in Singapore.

    Science.gov (United States)

    Lee, Yi Chuan; Chan, Soh Ha; Ren, Ee Chee

    2008-11-01

    Killer cell immunoglobulin-like receptors (KIR) gene frequencies have been shown to be distinctly different between populations and contribute to functional variation in the immune response. We have investigated KIR gene frequencies in 370 individuals representing three Asian populations in Singapore and report here the distribution of 14 KIR genes (2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 3DL1, 3DL2, 3DL3, 3DS1) with two pseudogenes (2DP1, 3DP1) among Singapore Chinese (n = 210); Singapore Malay (n = 80), and Singapore Indian (n = 80). Four framework genes (KIR3DL3, 3DP1, 2DL4, 3DL2) and a nonframework pseudogene 2DP1 were detected in all samples while KIR2DS2, 2DL2, 2DL5, and 2DS5 had the greatest significant variation across the three populations. Fifteen significant linkage patterns, consistent with associations between genes of A and B haplotypes, were observed. Eighty-four distinct KIR profiles were determined in our populations, 38 of which had not been described in other populations. KIR haplotype studies were performed using nine Singapore Chinese families comprising 34 individuals. All genotypes could be resolved into corresponding pairs of existing haplotypes with eight distinct KIR genotypes and eight different haplotypes. The haplotype A2 with frequency of 63.9% was dominant in Singapore Chinese, comparable to that reported in Korean and Chinese Han. The A haplotypes predominate in Singapore Chinese, with ratio of A to B haplotypes of approximately 3:1. Comparison with KIR frequencies in other populations showed that Singapore Chinese shared similar distributions with Chinese Han, Japanese, and Korean; Singapore Indian was found to be comparable with North Indian Hindus while Singapore Malay resembled the Thai.

  1. Induced change of formative processes in pepper (Capsicum annuum L. ). I. Effect of mutagenic treatment on the crossingover frequency of the linked and recombination of unlinked marker genes

    Energy Technology Data Exchange (ETDEWEB)

    Samovol, A.P.

    1986-05-01

    The effect of mutagenic treatment of the F/sub 1/ seeds of pepper on the crossingover frequency in the al/sub 2/-b segment, monohybrid and dihybrid segregation for the unlinked marker genes al/sub 2/ and pi was studied. It has been demonstrated that treatment leads to a significant reduction in the crossover frequency in the al/sub 2/-b zone. Highly significant differences between the control and individual treatment of the hybrid seeds indicated reduction in recombinations due to the mutagens used. A case of induced deviation in independent segregation of al/sub 2/ and pi, i.e., quasilinkage has been recorded.

  2. [Analysis of the meiotic recombination frequency in transgenic tomato hybrids expressing recA and NLS-recA-licBM3 genes].

    Science.gov (United States)

    Komakhin, R A; Komakhina, V V; Miliukova, N A; Zhuchenko, A A

    2012-01-01

    To study and induce meiotic recombination in plants, we generated and analyzed transgenic tomato hybrids F1-RecA and F1-NLS-recA-LicBM3 expressing, respectively, the recA gene of Escherichia coli and the NLS-recA-licBM3 gene. It was found that the recA and NLS-recA-licBM3 genes are inherited through the maternal and paternal lineages, they have no selective influence on the pollen and are contained in tomato F1-RecA and F1-NLS-RecA-LicBM3 hybrids outside the second chromosome in the hemizygous state. The comparative analysis of the meiotic recombination frequency (rf) in the progenies of the transgenic and nontransgenic hybrids showed that only the expression of the recA gene of E. coli in cells of the F1-RecA plants produced a 1.2-1.5-fold increase in the frequency of recombination between some linked marker genes of the second chromosome of tomato.

  3. Imperfect conformation of experimental and epidemiological data for frequency of RET/РТС gene rearrangements in papillary thyroid carcinoma for the Chernobyl accident

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    Ushenkova L.N.

    2013-12-01

    Full Text Available In an overview and analytical study of the epidemiological data on the frequency of RET/РТС gene rearrangements in sporadic and radiogenic (patients after radiotherapy, residents of contaminated after the Chernobyl disaster areas, victims after the atomic bombings, etc. carcinomas of the thyroid gland were examined. In general, the observed epidemiological laws were confirmed in radiobiology experiments by irradiation of different cultures of thyroid cells and ex vivo with the exception of Chernobyl cohorts. Induction of RET/РТС gene rearrangements by 131l exposure in children carcinomas of Chernobyl residents in mice did not observe too. It is concluded that the situation with the frequency of RET/РТС rearrangements in thyroid carcinoma in Chernobyl cohorts once again confirms the multifactorial nature of the induction and development of these tumors with a contribution of radiation and non-radiation factors (iodine deficiency and different stresses.

  4. Frequency of V1016I and F1534C mutations in the voltage-gated sodium channel gene in Aedes aegypti in Venezuela.

    Science.gov (United States)

    Alvarez, Leslie C; Ponce, Gustavo; Saavedra-Rodriguez, Karla; Lopez, Beatriz; Flores, Adriana E

    2015-06-01

    The V1016I and F1534C mutations in the voltage-gated sodium channel gene have been associated with resistance to pyrethroids and DDT in Aedes aegypti mosquitoes. A study was carried out to determine the frequency of I1016 and C1534 by real-time PCR in five natural populations of Ae. aegypti in Venezuela during 2008, 2010 and 2012, as well as in a strain selected with 0.14 µg of deltamethrin for 15 generations. In natural populations, frequencies of I1016 varied between 0.01 and 0.37, and frequencies of C1534 between 0.35 and 1.0. In the Pampanito strain, the frequency of I1016 increased from 0.02 in F1 up to 0.5 in F15 and from 0.35 up to fixation for C1534 after selection with deltamethrin. The results showed that C1534 frequencies are higher than I1016 frequencies in natural populations of Ae. aegypti in Venezuela, and that deltamethrin selected the C1534 more rapidly than I1016. © 2014 Society of Chemical Industry.

  5. Polymorphisms of the coagulation factor Ⅶ gene and its plasma levels in relation to acute cerebral infarction differences in allelic frequencies between Chinese Han and European populations

    Institute of Scientific and Technical Information of China (English)

    康文英; 王鸿利; 熊立凡; 王学锋; 储海燕; 璩斌; 刘湘帆; 尹俊; 段宝华; 王振义

    2004-01-01

    Background Coagulation factor Ⅶ (F Ⅶ) levels in plasma are usually related to ischemic heart disease (IHD) and cerebral infarction shares many of the risk factors related to IHD. Is there any relationship between factor Ⅶ and cerebral infarction? We investigated the relationship between F Ⅶ and acute cerebral infarction and reported genotype frequencies and allelic frequencies of FⅦ gene polymorphisms in the Chinese Han population.Methods We recruited 62 patients with acute cerebral infarction confirmed by magnetic resonance imaging (MRI) from Ruijin Hospital, and 149 age-matched patients clinically free of vascular disease to act as controls. All of them were unrelated, and were from the Chinese Han population. FⅦ coagulant activity (FⅦc) was determined using an clotting assay, activated FⅦ (FⅦa) and FⅦ Ag were assayed using enzyme immunoassay kits. The FⅦ gene polymorphisms to be detected included-401G/T, -402G/A, 5'F7A1/A2, IVS7 and R353Q. 5'F7 and IVS7 were revealed by means of a PCR and direct agarose gel electrophoresis. The rest were examined by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results The results showed that FⅦc, FⅦAg and FⅦa were higher in the acute cerebral infarction group than in the control group (P<0.01, P<0.05, P<0.05, respectively). There were no significant differences in the genotype frequencies of FⅦ gene polymorphisms between the two groups. The allelic frequencies in the Chinese Han population were as follows: -401G/T (96.64/3.36), -402G/A (52.01/47.99), 5'F7A1/A2(96.64/3.36), IVS7 H5/H6/H7/H8 (0.34/52.35/46.98/0.34) and R353Q (95.64/4.36). There were significant differences (P<0.01, P<0.001, P<0.001, P<0.001, P<0.001, respectively) in these allelic frequencies between the Chinese Han and European populations.Conclusions The results indicate that increased plasma FⅦ levels may contribute to thrombosis in cerebral infarction. And there was no significant difference

  6. The Identification of Chemical and Bacterial Composition and Determination of FimH Gene Frequency of Kidney Stones of Iranian Patients

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    Ali Shojaeian

    2016-06-01

    Full Text Available Background There is rare study on the association between FimH and kidney stone formation in our country. Objectives Here we studied on stones and identified the bacteria in stones isolated from kidney stone disease and/or UTI patients attending to Hashemi-Nejad hospital (Tehran, Iran to find out a possible correlation between stone composition and the diseases. We also measure the frequency of fimH gene and its related protein in Escherichia coli isolated from the patients to clarify the effect of this gene in kidney stone formation. Patients and Methods In This observational-descriptive study, 40 kidney stone samples were gathered and the composition of each sample was determined. The frequency of fimH gene and its related protein was measured using PCR and protein extraction from separated E. coli bacteria. Results The most prevalence of stones belonged to calcium oxalate stones and the most frequent bacterium in kidney stones was E. coli. The frequency of fimH gene in isolated E. coli was 57.14%. Conclusions Our data indicated that almost all chemical types of kidney stones may involve in UTI and kidney stone formation. We also realized that although E. coli is a non-urea splitting bacteria, it is the most causative microorganism found in urine and stones. Finally we recognized that fimH gene is seen in the majority of kidney stone samples so it may have a role in formation of kidney stone, although it should be more clarified in future studies.

  7. Frequencies of 32 base pair deletion of the (Delta 32) allele of the CCR5 HIV-1 co-receptor gene in Caucasians: a comparative analysis.

    Science.gov (United States)

    Lucotte, Gérard

    2002-05-01

    The CCR5 gene encodes for the co-receptor for the major macrophage-tropics strains of human immunodeficiency virus (HIV-1), and a mutant allele of this gene (Delta 32) provide to homozygotes a strong resistance against infection by HIV. The frequency of the Delta 32 allele was investigated in 40 populations of 8842 non-infected subjects coming from Europe, the Middle-East and North Africa. A clear north-south decreasing gradient was evident for Delta 32 frequencies, with a significant correlation coefficient (r=0.83). The main frequency value of Delta 32 for Sweden, Norway, Denmark, Finland and Iceland (0.134) is significantly (chi(2)=63.818, PVikings might have been instrumental in disseminating the Delta 32 allele during the eighth to the tenth centuries during historical times. Possibly variola virus has discriminated the Delta 32 carriers in Europe since the eighth century AD, explaining the high frequency of the Delta 32 allele in Europe today.

  8. High frequency of virulence factor genes tdh, trh, and tlh in Vibrio parahaemolyticus strains isolated from a pristine estuary.

    Science.gov (United States)

    Gutierrez West, Casandra K; Klein, Savannah L; Lovell, Charles R

    2013-04-01

    Virulence factor genes encoding the thermostable direct hemolysin (tdh) and the thermostable direct hemolysin-related hemolysin (trh) are strongly correlated with virulence of the emergent human pathogen Vibrio parahaemolyticus. The gene encoding the thermolabile hemolysin (tlh) is also considered a signature molecular marker for the species. These genes are typically reported in very low percentages (1 to 2%) of nonclinical strains. V. parahaemolyticus strains were isolated from various niches within a pristine estuary (North Inlet, SC) and were screened for these genes using both newly designed PCR primers and more commonly used primers. DNA sequences of tdh and trh were recovered from 48% and 8.3%, respectively, of these North Inlet strains. The recovery of pathogenic V. parahaemolyticus strains in such high proportions from an estuarine ecosystem that is virtually free of anthropogenic influences indicates the potential for additional, perhaps environmental roles of the tdh and trh genes.

  9. Identification of KIF3A as a novel candidate gene for childhood asthma using RNA expression and population allelic frequencies differences.

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    Melinda Butsch Kovacic

    Full Text Available BACKGROUND: Asthma is a chronic inflammatory disease with a strong genetic predisposition. A major challenge for candidate gene association studies in asthma is the selection of biologically relevant genes. METHODOLOGY/PRINCIPAL FINDINGS: Using epithelial RNA expression arrays, HapMap allele frequency variation, and the literature, we identified six possible candidate susceptibility genes for childhood asthma including ADCY2, DNAH5, KIF3A, PDE4B, PLAU, SPRR2B. To evaluate these genes, we compared the genotypes of 194 predominantly tagging SNPs in 790 asthmatic, allergic and non-allergic children. We found that SNPs in all six genes were nominally associated with asthma (p<0.05 in our discovery cohort and in three independent cohorts at either the SNP or gene level (p<0.05. Further, we determined that our selection approach was superior to random selection of genes either differentially expressed in asthmatics compared to controls (p = 0.0049 or selected based on the literature alone (p = 0.0049, substantiating the validity of our gene selection approach. Importantly, we observed that 7 of 9 SNPs in the KIF3A gene more than doubled the odds of asthma (OR = 2.3, p<0.0001 and increased the odds of allergic disease (OR = 1.8, p<0.008. Our data indicate that KIF3A rs7737031 (T-allele has an asthma population attributable risk of 18.5%. The association between KIF3A rs7737031 and asthma was validated in 3 independent populations, further substantiating the validity of our gene selection approach. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates that KIF3A, a member of the kinesin superfamily of microtubule associated motors that are important in the transport of protein complexes within cilia, is a novel candidate gene for childhood asthma. Polymorphisms in KIF3A may in part be responsible for poor mucus and/or allergen clearance from the airways. Furthermore, our study provides a promising framework for the identification and

  10. Frequency of genes encoding erythromycin ribosomal methylases among Staphylococcus aureus clinical isolates with different D-phenotypes in Tehran, Iran

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    Sareh Sadat Hosseini

    2016-10-01

    Full Text Available Background and Objectives: Macrolide, lincosamide and streptogramin type B (MLSB antibiotics are important in the treatment of Staphylococcus aureus infections and existence of isolates with ability to resist against MLSB antibiotics is worrisome.Materials and Methods: In this cross sectional study, 101 S. aureus isolates were collected from patients of five selected hospitals in Tehran over a period of five months. Disk diffusion tests and differentiation between constitutive and inducible resistances were carried out by D-test. The presence of mecA, msrA, ermA and ermC genes were detected using PCR or multiplex PCR.Results: Out of 101 S. aureus isolates, 58 (57.4% were methicillin resistant and 57 (56.4% expressed resistance to erythromycin. The prevalence of constitutive MLSB (cMLSB, inducible MLSB (iMLSB and MS (Negative phenotype in all erythromycin resistant isolates were 71.9, 26.3 and 1.7%, respectively. Out of all the erythromycin resistant isolates, 57.8% harbored both ermA and ermC genes which possessed constitutive resistance. 8.7% of the isolates contained ermA gene alone which possessed inducible resistance with D phenotype and 5.2% of isolates just contained ermC gene which had inducible resistance with D+ phenotype. msrA gene was detected in 3.5% of the erythromycin resistant S. aureus isolates with constitutive resistance. None of the genes were detected among MS phenotypes.Conclusion: In this study, most of S. aureus isolates carried both ermA and ermC genes and there was a significant relationship (P value ≤ 0.05 between different resistance phenotypes and erm genes.Keywords: Staphylococcus aureus, D-test, Erm A, ErmC, MsrA

  11. Bilirubin UDP-Glucuronosyltransferase 1A1 (UGT1A1) Gene Promoter Polymorphisms and HPRT, Glycophorin A, and Micronuclei Mutant Frequencies in Human Blood

    Energy Technology Data Exchange (ETDEWEB)

    Grant, D; Hall, I J; Eastmond, D; Jones, I M; Bell, D A

    2004-10-06

    A dinucleotide repeat polymorphism (5-, 6-, 7-, or 8-TA units) has been identified within the promoter region of UDP-glucuronosyltransferase 1A1 gene (UGT1A1). The 7-TA repeat allele has been associated with elevated serum bilirubin levels that cause a mild hyperbilirubinemia (Gilbert's syndrome). Studies suggest that promoter transcriptional activity of UGT1A1 is inversely related to the number of TA repeats and that unconjugated bilirubin concentration increases directly with the number of TA repeat elements. Because bilirubin is a known antioxidant, we hypothesized that UGT1A1 repeats associated with higher bilirubin may be protective against oxidative damage. We examined the effect of UGT1A1 genotype on somatic mutant frequency in the hypoxanthine-guanine phosphoribosyl-transferase (HPRT) gene in human lymphocytes and the glycophorin A (GPA) gene of red blood cells (both N0, NN mutants), and the frequency of lymphocyte micronuclei (both kinetochore (K) positive or micronuclei K negative) in 101 healthy smoking and nonsmoking individuals. As hypothesized, genotypes containing 7-TA and 8-TA displayed marginally lower GPA{_}NN mutant frequency relative to 5/5, 5/6, 6/6 genotypes (p<0.05). In contrast, our analysis showed that lower expressing UGT1A1 alleles (7-TA and 8-TA) were associated with modestly increased HPRT mutation frequency (p<0.05) while the same low expression genotypes were not significantly associated with micronuclei frequencies (K-positive or K-negative) when compared to high expression genotypes (5-TA and 6-TA). We found weak evidence that UGT1A1 genotypes containing 7-TA and 8-TA were associated with increased GPA{_}N0 mutant frequency relative to 5/5, 5/6, 6/6 genotypes (p<0.05). These data suggest that UGT1A1 genotype may modulate somatic mutation of some types, in some cell lineages, by a mechanism not involving bilirubin antioxidant activity. More detailed studies examining UGT1A1 promoter variation, oxidant/antioxidant balance and

  12. Polymorphism attribution of cSNPs in cancer-related genes located in loss regions with a high frequency of HCC between HBV and health groups

    Institute of Scientific and Technical Information of China (English)

    WANG Juan; NI Hong; CHEN Li; CHEN Chengbin; SONG Wenqin

    2007-01-01

    Cancer-related genes harbored in the loss regions containing a high frequency of hepatocellular carcinoma (HCC) were selected.Related information was gathered and the coding single nucleotide polymorphism (cSNP) sequences were obtained from the single nucleotide polymorphism (SNP) database.The appropriate primers and oligonucleotide probes were then designed in accordance with the SNP sites,and subsequently,the gene chips for detecting SNPs were constructed.Genomic DNA was extracted from blood samples of healthy controls and from patients with HBV infection.The sequences,including the SNPs,were amplified via polymerase chain reaction (PCR) and labeled using digoxigenin deoxyuridine tri-phosphate (Dig-dUTP).The labeled products were then hybridized with the SNP chips.Results confirmed that the differences in allele frequencies of three SNPs EGFL3 (rs947345),Caspase9 (rs2308950),and E2F2 (rs3218171) were distinct between HBV-infected patients and controls,suggesting that these SNPs ocuring in high frequency in HBV-infected individuals may be associated with susceptibility to HCC.

  13. Rare, Low-Frequency, and Common Variants in the Protein-Coding Sequence of Biological Candidate Genes from GWASs Contribute to Risk of Rheumatoid Arthritis

    Science.gov (United States)

    Diogo, Dorothée; Kurreeman, Fina; Stahl, Eli A.; Liao, Katherine P.; Gupta, Namrata; Greenberg, Jeffrey D.; Rivas, Manuel A.; Hickey, Brendan; Flannick, Jason; Thomson, Brian; Guiducci, Candace; Ripke, Stephan; Adzhubey, Ivan; Barton, Anne; Kremer, Joel M.; Alfredsson, Lars; Sunyaev, Shamil; Martin, Javier; Zhernakova, Alexandra; Bowes, John; Eyre, Steve; Siminovitch, Katherine A.; Gregersen, Peter K.; Worthington, Jane; Klareskog, Lars; Padyukov, Leonid; Raychaudhuri, Soumya; Plenge, Robert M.

    2013-01-01

    The extent to which variants in the protein-coding sequence of genes contribute to risk of rheumatoid arthritis (RA) is unknown. In this study, we addressed this issue by deep exon sequencing and large-scale genotyping of 25 biological candidate genes located within RA risk loci discovered by genome-wide association studies (GWASs). First, we assessed the contribution of rare coding variants in the 25 genes to the risk of RA in a pooled sequencing study of 500 RA cases and 650 controls of European ancestry. We observed an accumulation of rare nonsynonymous variants exclusive to RA cases in IL2RA and IL2RB (burden test: p = 0.007 and p = 0.018, respectively). Next, we assessed the aggregate contribution of low-frequency and common coding variants to the risk of RA by dense genotyping of the 25 gene loci in 10,609 RA cases and 35,605 controls. We observed a strong enrichment of coding variants with a nominal signal of association with RA (p A [p.His266Gln]), and a noncoding variant, rs624988, reside on distinct haplotypes and independently contribute to the risk of RA (p = 4.6 × 10−6). Overall, our results indicate that variants (distributed across the allele-frequency spectrum) within the protein-coding portion of a subset of biological candidate genes identified by GWASs contribute to the risk of RA. Further, we have demonstrated that very large sample sizes will be required for comprehensively identifying the independent alleles contributing to the missing heritability of RA. PMID:23261300

  14. Spectrum and frequency of GJB2, GJB6 and SLC26A4 gene mutations among nonsyndromic hearing loss patients in eastern part of India.

    Science.gov (United States)

    Adhikary, Bidisha; Ghosh, Sudakshina; Paul, Silpita; Bankura, Biswabandhu; Pattanayak, Arup Kumar; Biswas, Subhradev; Maity, Biswanath; Das, Madhusudan

    2015-12-01

    Genetically caused nonsyndromic hearing loss is highly heterogeneous. Inspite of this large heterogeneity, mutations in the genes GJB2, GJB6 and SLC26A4 are major contributors. The mutation spectrum of these genes varies among different ethnic groups. Only a handful of studies focused on the altered genetic signature of these genes in different demographic regions of India but never focused on the eastern part of the country. Our study for the first time aimed to characterize the mutation profile of these genes in hearing loss patients of West Bengal state, India. Mutations in GJB2, GJB6 and SLC26A4 genes were screened by bidirectional sequencing from 215 congenital nonsyndromic hearing loss patients. Radiological diagnosis was performed in patients with SLC26A4 mutations by temporal bone CT scan. The study revealed that 4.65% and 6.97% patients had monoallelic and biallelic GJB2 mutations respectively. Six mutations were identified, p.W24X being the most frequent one accounting for 71.05% of the mutated alleles. Mutations in GJB6 including the previously identified deletion mutation (GJB6-D13S1830) were not identified in our study. Further, no patients harbored biallelic mutations in the SLC26A4 gene or the common inner ear malformation Enlarged Vestibular Aqueduct (EVA). The mutation profile of GJB2 in our study is distinct from other parts of India, suggesting that the mutation spectrum of this gene varies with ethnicity and geographical origin. The absence of GJB6 mutations and low frequency of SLC26A4 mutations suggest that additional genetic factors may also contribute to this disease.

  15. Mutation Frequency of the Major Frontotemporal Dementia Genes, MAPT, GRN and C9ORF72 in a Turkish Cohort of Dementia Patients

    Science.gov (United States)

    Guven, Gamze; Lohmann, Ebba; Bras, Jose; Gibbs, J. Raphael; Gurvit, Hakan; Bilgic, Basar; Hanagasi, Hasmet; Rizzu, Patrizia; Heutink, Peter; Emre, Murat; Erginel-Unaltuna, Nihan; Just, Walter; Hardy, John; Singleton, Andrew; Guerreiro, Rita

    2016-01-01

    ‘Microtubule-associated protein tau’ (MAPT), ‘granulin’ (GRN) and ‘chromosome 9 open reading frame72’ (C9ORF72) gene mutations are the major known genetic causes of frontotemporal dementia (FTD). Recent studies suggest that mutations in these genes may also be associated with other forms of dementia. Therefore we investigated whether MAPT, GRN and C9ORF72 gene mutations are major contributors to dementia in a random, unselected Turkish cohort of dementia patients. A combination of whole-exome sequencing, Sanger sequencing and fragment analysis/Southern blot was performed in order to identify pathogenic mutations and novel variants in these genes as well as other FTD-related genes such as the ‘charged multivesicular body protein 2B’ (CHMP2B), the ‘FUS RNA binding protein’ (FUS), the ‘TAR DNA binding protein’ (TARDBP), the ‘sequestosome1’ (SQSTM1), and the ‘valosin containing protein’ (VCP). We determined one pathogenic MAPT mutation (c.1906C>T, p.P636L) and one novel missense variant (c.38A>G, p.D13G). In GRN we identified a probably pathogenic TGAG deletion in the splice donor site of exon 6. Three patients were found to carry the GGGGCC expansions in the non-coding region of the C9ORF72 gene. In summary, a complete screening for mutations in MAPT, GRN and C9ORF72 genes revealed a frequency of 5.4% of pathogenic mutations in a random cohort of 93 Turkish index patients with dementia. PMID:27632209

  16. High frequency of hypermethylation at the 14-3-3 σ locus leads to gene silencing in breast cancer

    Science.gov (United States)

    Ferguson, Anne T.; Evron, Ella; Umbricht, Christopher B.; Pandita, Tej K.; Chan, Timothy A.; Hermeking, Heiko; Marks, Jeffrey R.; Lambers, Anouk R.; Futreal, P. Andrew; Stampfer, Martha R.; Sukumar, Saraswati

    2000-01-01

    Expression of 14-3-3 σ (σ) is induced in response to DNA damage, and causes cells to arrest in G2. By SAGE (serial analysis of gene expression) analysis, we identified σ as a gene whose expression is 7-fold lower in breast carcinoma cells than in normal breast epithelium. We verified this finding by Northern blot analysis. Remarkably, σ mRNA was undetectable in 45 of 48 primary breast carcinomas. Genetic alterations at σ such as loss of heterozygosity were rare (1/20 informative cases), and no mutations were detected (0/34). On the other hand, hypermethylation of CpG islands in the σ gene was detected in 91% (75/82) of breast tumors and was associated with lack of gene expression. Hypermethylation of σ is functionally important, because treatment of σ-non-expressing breast cancer cell lines with the drug 5-aza-2′-deoxycytidine resulted in demethylation of the gene and synthesis of σ mRNA. Breast cancer cells lacking σ expression showed increased number of chromosomal breaks and gaps when exposed to γ-irradiation. Therefore, it is possible that loss of σ expression contributes to malignant transformation by impairing the G2 cell cycle checkpoint function, thus allowing an accumulation of genetic defects. Hypermethylation and loss of σ expression are the most consistent molecular alterations in breast cancer identified so far. PMID:10811911

  17. Frequency of polymorphic variants in CRHR1, GLCCI1 and FCER2 genes in healthy and asthmatic Tamilian population

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    Revathy N.

    2016-10-01

    Conclusions: MAF of rs 242941, rs 28364072 and rs 37972 were 0.51, 0.33 and 0.38, respectively in Tamilian population which were significantly different from various global populations. The frequency distribution found helps to further with ICS response association studies in larger cohorts of asthma patients. [Int J Basic Clin Pharmacol 2016; 5(5.000: 1831-1838

  18. Sensitivity and Frequencies of Dystrophin Gene Mutations in Thai DMD/BMD Patients As Detected by Multiplex PCR

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    Thanyachai Sura

    2008-01-01

    Full Text Available Background: Duchenne muscular dystrophy (DMD, a lethal X-linked disease affecting 1 in 3500 male births, and its more benign variant, Becker muscular dystrophy (BMD, are caused by mutations in the dystrophin gene. Because of its large size, analysing the whole gene is impractical. Methods have been developed to detect the commonest mutations i.e. the deletions of the exons. Although these tests are highly specific, their sensitivity is inherently limited by the prevalence of deletions, which differs among different populations.

  19. Direct estimation of the recombination frequency between the RB1 gene and two closely linked microsatellites using sperm typing.

    Science.gov (United States)

    Girardet, A; Lien, S; Leeflang, E P; Beaufrère, L; Tuffery, S; Munier, F; Arnheim, N; Claustres, M; Pellestor, F

    1999-01-01

    In this study, single sperm typing has been used for high-resolution recombination analysis between the retinoblastoma gene and two closely linked extragenic microsatellites (D13S284 and D13S1307). The analysis of 1198 single sperm from three donors allowed the determination of recombination fractions between RB1.20 and D13S284 and RB1.20 and D13S1307 of 0.022 and 0.033, respectively. These results show that RB1 gene and the two microsatellites are closely linked, which validates their potential use in indirect genetic diagnosis of retinoblastoma.

  20. Simultaneous Analysis of SEPT9 Promoter Methylation Status, Micronuclei Frequency, and Folate-Related Gene Polymorphisms: The Potential for a Novel Blood-Based Colorectal Cancer Biomarker.

    Science.gov (United States)

    Ravegnini, Gloria; Zolezzi Moraga, Juan Manuel; Maffei, Francesca; Musti, Muriel; Zenesini, Corrado; Simeon, Vittorio; Sammarini, Giulia; Festi, Davide; Hrelia, Patrizia; Angelini, Sabrina

    2015-12-01

    One challenge in colorectal cancer (CRC) is identifying novel biomarkers to be introduced in screening programs. The present study investigated the promoter methylation status of the SEPT9 gene in peripheral blood samples of subjects' positive fecal occult blood test (FOBT). In order to add new insights, we investigated the association between SEPT9 promoter methylation and micronuclei frequency, and polymorphisms in the folate-related pathway genes. SEPT9 promoter methylation, micronuclei frequency, and genotypes were evaluated on 74 individuals' FOBT positive. Individuals were subjected to a colonoscopy that provided written informed consent for study participation. SEPT9 promoter methylation status was significantly lower in the CRC group than controls (p = 0.0006). In contrast, the CaCo2 cell-line, analyzed as a tissue specific model of colon adenocarcinoma, showed a significantly higher percentage of SEPT9 promoter methylation compared to the CRC group (p < 0.0001). Linear regression analysis showed an inverse correlation between micronuclei frequency and the decrease in the methylation levels of SEPT9 promoter region among CRC patients (β = -0.926, p = 0.0001). With regard to genotype analysis, we showed the involvement of the DHFR polymorphism (rs70991108) in SEPT9 promoter methylation level in CRC patients only. In particular, the presence of at least one 19 bp del allele significantly correlates with decreased SEPT9 promoter methylation, compared to the 19 bp ins/ins genotype (p = 0.007). While remaining aware of the strengths and limitations of the study, this represents the first evidence of a novel approach for the early detection of CRC, using SEPT9 promoter methylation, micronuclei frequency and genotypes, with the potential to improve CRC risk assessment.

  1. Molecular spectrum of somatic EGFR and KRAS gene mutations in non small cell lung carcinoma: determination of frequency, distribution pattern and identification of novel variations in Indian patients.

    Science.gov (United States)

    Das, Bibhu Ranjan; Bhaumik, Sangeet; Ahmad, Firoz; Mandsaurwala, Aziz; Satam, Heena

    2015-07-01

    Somatic mutations of EGFR and KRAS gene represent the most common alterations currently known in NSCLC patients. This study explored the frequency, distribution pattern of EGFR and KRAS mutations in Indian patients. The frequencies of EGFR and KRAS mutations were 29 % (116/400) and 4.5 % (6/132) respectively. Both EGFR and KRAS mutations were prevalent in females, and a trend towards higher mutation frequency was seen in patients under ≥ 60 years age. The presence of EGFR and KRAS mutations were higher in adenocarcinomas in comparison to other histological subtype. Sequencing analysis of EGFR exon 18 revealed Inframe deletion (G709_T710 > A) and missense mutation (K713R). Among exon 19 positive cases, 49.3 % (37/75) were in-frame deletions, of which E746_A750del was frequent. Similarly, ~47 % (35/75) cases showed complex mutation involving indel. Among mutations in exon 20 (N = 9), 8 were substitutions, one showed duplication, while all exon 21 mutations were of the missense types with L858R as the most recurrent type. Sequencing analysis of KRAS exon 1 revealed three different types codon 12 substitutions resulting in c34G > T (G12C) (n = 4), c.35G > A (G12D) (n = 1), and c.35G > T (G12V) (n = 1). In conclusion, the present study is an example of molecular diversity of EGFR and KRAS gene in Indian patients and further confirms that the frequency of EGFR and KRAS mutations varies considerably globally. To the best of our knowledge, this is the first Indian study to evaluate KRAS mutation. The current study also served to identify novel variations that added new insights into the genetic heterogeneity of NSCLC.

  2. Simultaneous Analysis of SEPT9 Promoter Methylation Status, Micronuclei Frequency, and Folate-Related Gene Polymorphisms: The Potential for a Novel Blood-Based Colorectal Cancer Biomarker

    Directory of Open Access Journals (Sweden)

    Gloria Ravegnini

    2015-12-01

    Full Text Available One challenge in colorectal cancer (CRC is identifying novel biomarkers to be introduced in screening programs. The present study investigated the promoter methylation status of the SEPT9 gene in peripheral blood samples of subjects’ positive fecal occult blood test (FOBT. In order to add new insights, we investigated the association between SEPT9 promoter methylation and micronuclei frequency, and polymorphisms in the folate-related pathway genes. SEPT9 promoter methylation, micronuclei frequency, and genotypes were evaluated on 74 individuals’ FOBT positive. Individuals were subjected to a colonoscopy that provided written informed consent for study participation. SEPT9 promoter methylation status was significantly lower in the CRC group than controls (p = 0.0006. In contrast, the CaCo2 cell-line, analyzed as a tissue specific model of colon adenocarcinoma, showed a significantly higher percentage of SEPT9 promoter methylation compared to the CRC group (p < 0.0001. Linear regression analysis showed an inverse correlation between micronuclei frequency and the decrease in the methylation levels of SEPT9 promoter region among CRC patients (β = −0.926, p = 0.0001. With regard to genotype analysis, we showed the involvement of the DHFR polymorphism (rs70991108 in SEPT9 promoter methylation level in CRC patients only. In particular, the presence of at least one 19 bp del allele significantly correlates with decreased SEPT9 promoter methylation, compared to the 19 bp ins/ins genotype (p = 0.007. While remaining aware of the strengths and limitations of the study, this represents the first evidence of a novel approach for the early detection of CRC, using SEPT9 promoter methylation, micronuclei frequency and genotypes, with the potential to improve CRC risk assessment.

  3. Increased frequency of {gamma}{delta} T cells in cerebrospinal fluid and peripheral blood of patients with multiple sclerosis: Reactivity, cytotoxicity, and T cell receptor V gene rearrangements

    Energy Technology Data Exchange (ETDEWEB)

    Stinissen, P.; Vandevyver, C.; Medaer, R. [Dr. L. Willems Institute, Diepenbeek (Belgium)] [and others

    1995-05-01

    Infiltrating {gamma}{delta} T cells are potentially involved in the central nervous system demyelination in multiple sclerosis (MS). To further study this hypothesis, we analyzed the frequency and functional properties of {gamma}{delta} T cells in peripheral blood (PB) and paired cerebrospinal fluid (CSF) of patients with MS and control subjects, including patients with other neurologic diseases (OND) and healthy individuals. The frequency analysis was performed under limiting dilution condition using rIL-2 and PHA. After PHA stimulation, a significantly increased frequency of {gamma}{delta} T cells was observed in PB and in CSF of MS patients as compared with PB and CSF of patients with OND. The frequency was represented equally in OND patients and normal individuals. Similarly, the IL-2-responsive {gamma}{delta} T cells occurred at a higher frequency in PB of MS than of control subjects. Forty-three percent of the {gamma}{delta} T cell clones isolates from PB and CSF of MS patients responded to heat shock protein (HSP70) but not HSP65, whereas only 2 of 30 control {gamma}{delta} T cell clones reacted to the HSP. The majority of the {gamma}{delta} T cell clones were able to induce non-MHC-restricted cytolysis of Daudi cells. All clones displayed a substantial reactivity to bacterial superantigens staphylococcal enterotoxin B and toxic shock syndrome toxin-1, irrespective of their {gamma}{delta} V gene usage. Furthermore, the {gamma}{delta} T cell clones expressed predominantly TCRDV2 and GV2 genes, whereas the clones derived from CSF of MS patients expressed either DV1 or DV2 genes. The obtained {gamma}{delta} clones, in general, represented rather heterogeneous clonal origins, even though a predominant clonal origin was found in a set of 10 {gamma}{delta} clones derived from one patient with MS. The present study provides new evidence supporting a possible role of {gamma}{delta} T cells in the secondary inflammatory processes in MS. 39 refs., 5 figs., 4 tabs.

  4. Frequency of mitochondrial 12S rRNA gene A1555G and 961 insC mutations among children with sensorineural deafness in China

    Institute of Scientific and Technical Information of China (English)

    Xia Xu; Guangqian Xing; Qinjun Wei; Zhibin Chen; Hongbo Cheng; Xin Cao; Xingkuan Bu

    2006-01-01

    Objective: To investigate the frequency of mitochondrial 12S rRNA gene A1555G and 961 insC mutations among Chinese with sensorineural deafness. Methods: Blood samples from 78 sporadic cases with sensorineural deafness were obtained and DNA was extracted from the leukocytes, then the mitochondrial DNA target fragments were amplified by polymerase chain reaction(PCR). The 1555G mutations were detected by BsmA I restriction endonuclease digestion, every fragment was analyzed by sequencing; All the 961 insC mutation were detected by direct sequencing. Results: The percent age of A1555G mutation and mt961C insertion were 6.4% and 2.6% in the hearing-impaired Chinese subjects respectively. Conclusion: A1555G and 96linsC mutations in mitochondrial DNA 12S rRNA gene regions may play a role in the pathogenesis of hearing loss in the sporadic cases.

  5. Dose- and time-dependent changes of micronucleus frequency and gene expression in the progeny of irradiated cells: Two components in radiation-induced genomic instability?

    Energy Technology Data Exchange (ETDEWEB)

    Huumonen, Katriina [University of Eastern Finland, Department of Environmental Science, P.O. Box 1627, 70211 Kuopio (Finland); Korkalainen, Merja [National Institute for Health and Welfare, Department of Environmental Health, P.O. Box 95, 70701 Kuopio (Finland); Boman, Eeva; Heikkilä, Janne [Kuopio University Hospital, Cancer Center, P.O. Box 1777, 70211 Kuopio (Finland); Höytö, Anne [University of Eastern Finland, Department of Environmental Science, P.O. Box 1627, 70211 Kuopio (Finland); Lahtinen, Tapani [Kuopio University Hospital, Cancer Center, P.O. Box 1777, 70211 Kuopio (Finland); Luukkonen, Jukka [University of Eastern Finland, Department of Environmental Science, P.O. Box 1627, 70211 Kuopio (Finland); Viluksela, Matti [National Institute for Health and Welfare, Department of Environmental Health, P.O. Box 95, 70701 Kuopio (Finland); Naarala, Jonne [University of Eastern Finland, Department of Environmental Science, P.O. Box 1627, 70211 Kuopio (Finland); Juutilainen, Jukka, E-mail: jukka.juutilainen@uef.fi [University of Eastern Finland, Department of Environmental Science, P.O. Box 1627, 70211 Kuopio (Finland)

    2014-07-15

    Highlights: • Development with time of radiation-induced genomic instability (RIGI) was studied. • Dose–response of micronuclei showed marked time-dependent changes. • A new model assuming two components in RIGI was found to fit with the data. • The persisting component of RIGI seems to be independent of dose above a threshold. • Increasing heterogeneity was characteristic to delayed gene expression changes. - Abstract: Murine embryonic C3H/10T½ fibroblasts were exposed to X-rays at doses of 0.2, 0.5, 1, 2 or 5 Gy. To follow the development of radiation-induced genomic instability (RIGI), the frequency of micronuclei was measured with flow cytometry at 2 days after exposure and in the progeny of the irradiated cells at 8 and 15 days after exposure. Gene expression was measured at the same points in time by PCR arrays profiling the expression of 84 cancer-relevant genes. The micronucleus results showed a gradual decrease in the slope of the dose–response curve between days 2 and 15. The data were consistent with a model assuming two components in RIGI. The first component is characterized by dose-dependent increase in micronuclei. It may persist more than ten cell generations depending on dose, but eventually disappears. The second component is more persistent and independent of dose above a threshold higher than 0.2 Gy. Gene expression analysis 2 days after irradiation at 5 Gy showed consistent changes in genes that typically respond to DNA damage. However, the consistency of changes decreased with time, suggesting that non-specificity and increased heterogeneity of gene expression are characteristic to the second, more persistent component of RIGI.

  6. Phylogenomic analyses resolve an ancient trichotomy at the base of Ischyropsalidoidea (Arachnida, Opiliones) despite high levels of gene tree conflict and unequal minority resolution frequencies.

    Science.gov (United States)

    Richart, Casey H; Hayashi, Cheryl Y; Hedin, Marshal

    2016-02-01

    Phylogenetic resolution of ancient rapid radiations has remained problematic despite major advances in statistical approaches and DNA sequencing technologies. Here we report on a combined phylogenetic approach utilizing transcriptome data in conjunction with Sanger sequence data to investigate a tandem of ancient divergences in the harvestmen superfamily Ischyropsalidoidea (Arachnida, Opiliones, Dyspnoi). We rely on Sanger sequences to resolve nodes within and between closely related genera, and use RNA-seq data from a subset of taxa to resolve a short and ancient internal branch. We use several analytical approaches to explore this succession of ancient diversification events, including concatenated and coalescent-based analyses and maximum likelihood gene trees for each locus. We evaluate the robustness of phylogenetic inferences using a randomized locus sub-sampling approach, and find congruence across these methods despite considerable incongruence across gene trees. Incongruent gene trees are not recovered in frequencies expected from a simple multispecies coalescent model, and we reject incomplete lineage sorting as the sole contributor to gene tree conflict. Using these approaches we attain robust support for higher-level phylogenetic relationships within Ischyropsalidoidea.

  7. Frequency of Aminoglycoside-Resistance Genes in Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates from Hospitalized Patients

    Science.gov (United States)

    Mahdiyoun, Seyed Mohsen; Kazemian, Hossein; Ahanjan, Mohammad; Houri, Hamidreza; Goudarzi, Mehdi

    2016-01-01

    Background Staphylococcus aureus is one of the most important causative agents in community- and hospital-acquired infections. Aminoglycosides are powerful bactericidal drugs that are often used in combination with beta-lactams or glycopeptides to treat staphylococcal infections. Objectives The main objective of the present study was to determine the prevalence of aminoglycoside resistance among methicillin-resistant Staphylococcus aureus (MRSA) isolates in hospitalized patients in Sari and Tehran, Iran. Methods In this study, 174 MRSA strains isolated from different clinical samples, such as blood, sputum, tracheal exudates, bronchus, pleura, urine, wounds, and catheters, were collected from hospitalized patients in Tehran and Sari during 2014. Antibiotic susceptibility testing was performed against nine antibiotics with the Kirby-Bauer disk diffusion method according to CLSI guidelines. The MRSA strains were examined with oxacillin and cefoxitin disks. MRSA was then validated by detection of the mecA gene. PCR was used to evaluate the prevalence of the aminoglycoside-resistance genes aac (6’)-Ie/aph (2”), aph (3’)-IIIa, and ant (4’) among the MRSA isolates. Results The results of drug susceptibility testing showed that the highest rate of resistance was against erythromycin in Tehran (84.4%) and gentamicin (71.7%) in Sari. All isolates were sensitive to vancomycin, and all strains harbored the mecA gene. The aac (6’)-Ie/aph (2”), aph (3’)-IIIa, and ant (4’)-Ia genes were detected among 134 (77%), 119 (68.4%), and 122 (70.1%) of the isolates, respectively. Conclusions The present study showed a high prevalence of aminoglycoside-resistance genes among MRSA isolates in two cities in Iran.

  8. [The influence of ITGB3 gene polymorphism on the frequency of arterial hypertension in patients with acute coronary syndrome].

    Science.gov (United States)

    Zotova, T Iu; Miandina, G I; Frolov, V A; Komarova, A G; Zotov, A K

    2013-01-01

    PLA polymorphism of platelet integrin receptor, GpIIIa glycoprotein, (PLA polymorphism of the ITGB3 gene) is associated with the risk of myocardial infarction and CHD especially in young subjects. We analyzed ITGB3 gene polymorphism in patients with acute coronary insufficiency. It was shown that increased AP and altered blood lipid spectrum in the acute period of disease in carriers of the PLA allele (PLA1/PLA2 and PLA2/PLA2 genotypes) can be regarded as manifestations of stress reaction. The data obtained indicate that the PLA2 allele is a predictor of complications of acute coronary insufficiency. This observation is of importance for the choice of adequate therapy for the patients with this disorder.

  9. Blood group and protein polymorphism gene frequencies for the andalusian horse breed: a comparison with four american horse breeds

    OpenAIRE

    Aguilar Sánchez, P.; Rodríguez-Gallardo, P.P.; Andrés Cara, D.F. de; J.L Vega-Pla

    1992-01-01

    Gene frecuencies at seventeen blood group and protein polymorphism loci for the andalusian horse breed are given. Standard methods of starch and polyacrylamide gel electrophoresis were used to identify inherited variants at the following enzyme and other protein loci: albumin (Al), transferrin (Tf), carboxylesterase (Es), A1B glycoprotein (Xk), vitamin D binding protein (Gc), protease inhibitor (Pi), 6-phosphogluconate dehydrogenase (PGD), phosphoglucomutase (PGM) and glucosephosphate isomera...

  10. ama1 Genes of Sympatric Plasmodium vivax and P. falciparum from Venezuela Differ Significantly in Genetic Diversity and Recombination Frequency

    OpenAIRE

    Ord, RL; Tami, A; Sutherland, CJ

    2008-01-01

    BACKGROUND: We present the first population genetic analysis of homologous loci from two sympatric human malaria parasite populations sharing the same human hosts, using full-length sequences of ama1 genes from Plasmodium vivax and P. falciparum collected in the Venezuelan Amazon. METHODOLOGY/PRINCIPAL FINDINGS: Significant differences between the two species were found in genetic diversity at the ama1 locus, with 18 distinct haplotypes identified among the 73 Pvama1 sequences obtained, compa...

  11. Frequency of polymorphism -262 c/t in catalase gene and oxidative damage in Slovak children with bronchial asthma.

    Science.gov (United States)

    Babusikova, Eva; Jesenak, Milos; Evinova, Andrea; Banovcin, Peter; Dobrota, Dusan

    2013-12-01

    Bronchial asthma is a complex disease in which genetic factors, environmental factors and oxidative damage are responsible for the initiation and modulation of disease progression. If antioxidant mechanisms fail, reactive oxygen species damage the biomolecules followed by progression of the disease. Catalase is one of the most important endogenous enzymatic antioxidants. In the present study, we examined the hypothesis that increased oxidative damage and polymorphism in the CAT gene (-262 promoter region, C/T) are associated with childhood bronchial asthma. Genotyping of the polymorphisms in the CAT gene in healthy (249) and asthmatic children (248) was performed using polymerase chain reaction-restriction fragment length polymorphism. Markers of oxidative damage: content of sulfhydryl groups and thiobarbituric acid-reactive substances were determined by spectrophotometry in children. The TT genotype of catalase was more frequent among the asthmatic patients (22.6%) than in healthy children (4.8%) (odds ratio=5.63; 95% confidence interval=2.93-10.81, P<.001). The amount of sulfhydryl groups decreased significantly and conversely, the content of thiobarbituric acid-reactive substances increased significantly in bronchial asthma and in catalase TT genotype compared to other catalase genotypes of this gene. These results suggest that catalase polymorphism might participate in development of bronchial asthma and in enhanced oxidative damage in asthmatic children. Genetic variation of enzymatic antioxidants may modulate disease risk. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

  12. High Frequency of Pulmonary Hypertension-Causing Gene Mutation in Chinese Patients with Chronic Thromboembolic Pulmonary Hypertension.

    Directory of Open Access Journals (Sweden)

    Qunying Xi

    Full Text Available The pathogenesis of chronic thromboembolic pulmonary hypertension (CTEPH is unknown. Histopathologic studies revealed that pulmonary vasculature lesions similar to idiopathic pulmonary arterial hypertension (PAH existed in CTEPH patients as well. It's well-known that genetic predisposition plays an important role in the mechanism of PAH. So we hypothesized that PAH-causing gene mutation might exist in some CTEPH patients and act as a background to facilitate the development of CTEPH. In this study, we analyzed 7 PAH-causing genes including BMPR2, ACVRL1, ENG, SMAD9, CAV1, KCNK3, and CBLN2 in 49 CTEPH patients and 17 patients recovered from pulmonary embolism (PE but without pulmonary hypertension(PH. The results showed that the nonsynonymous mutation rate in CTEPH patients is significantly higher than that in PE without PH patients (25 out of 49 (51% CTEPH patients vs. 3 out of 17 PE without PH patients (18%; p = 0.022. Four CTEPH patients had the same point mutation in ACVRL1 exon 10 (c.1450C>G, a mutation approved to be associated with PH in a previous study. In addition, we identified two CTEPH associated SNPs (rs3739817 and rs55805125. Our results suggest that PAH-causing gene mutation might play an important role in the development of CTEPH.

  13. Polymorphisms and allele frequencies of glutathione S-transferases A1 and P1 genes in the Polish population.

    Science.gov (United States)

    Skrzypczak-Zielinska, M; Zakerska-Banaszak, O; Tamowicz, B; Sobieraj, I; Drweska-Matelska, N; Szalata, M; Slomski, R; Mikstacki, A

    2015-03-31

    Glutathione S-transferases (GST) A1 and P1 are crucial enzymes involved in the biotransformation of drugs, carcinogens, and toxins, and their activity may influence drug response, susceptibility to diseases, and carcinogenesis. The genes encoding these enzymes, GSTA1 and GSTP1, have been examined in many studies because of their genetic variability, which may affect enzymatic activity. The goal of this study was to determine the distribution of the alleles GSTA1*A/*B and GSTP1*A, *B, and *C in the Polish population. A total of 160 subjects from the Polish population were genotyped for 2 polymorphisms (I105V and A114V) in the GSTP1 gene using pyrosequencing. The promoter region of the GSTA1 gene was screened using sequencing. The detected variants were subjected to haplotype analysis. We found that the distribution of the alleles GSTA1*A/*B and GSTP1*A, *B, and *C in the Polish population correspond to the results of studies in Caucasians. Furthermore, we identified additional single nucleotide polymorphisms, excluding 3 well-known changes (G-52A, C-69T, T-567G), which are linked to alleles GSTA1*A/*B, that affect enzyme activity. A total of 4 haplotypes were identified in 160 Polish individuals.

  14. Alpha-1 antitrypsin Pi*Z gene frequency and Pi*ZZ genotype numbers worldwide: an update

    Science.gov (United States)

    Blanco, Ignacio; Bueno, Patricia; Diego, Isidro; Pérez-Holanda, Sergio; Casas-Maldonado, Francisco; Esquinas, Cristina; Miravitlles, Marc

    2017-01-01

    In alpha-1 antitrypsin deficiency (AATD), the Z allele is present in 98% of cases with severe disease, and knowledge of the frequency of this allele is essential from a public health perspective. However, there is a remarkable lack of epidemiological data on AATD worldwide, and many of the data currently used are outdated. Therefore, the objective of this study was to update the knowledge of the frequency of the Z allele to achieve accurate estimates of the prevalence and number of Pi*ZZ genotypes worldwide based on studies performed according to the following criteria: 1) samples representative of the general population, 2) AAT phenotyping characterized by adequate methods, and 3) measurements performed using a coefficient of variation calculated from the sample size and 95% confidence intervals. Studies fulfilling these criteria were used to develop maps with an inverse distance weighted (IDW)-interpolation method, providing numerical and graphical information of Pi*Z distribution worldwide. A total of 224 cohorts from 65 countries were included in the study. With the data provided by these cohorts, a total of 253,404 Pi*ZZ were estimated worldwide: 119,594 in Europe, 91,490 in America and Caribbean, 3,824 in Africa, 32,154 in Asia, 4,126 in Australia, and 2,216 in New Zealand. In addition, the IDW-interpolation maps predicted Pi*Z frequencies throughout the world even in some areas that lack real data. In conclusion, the inclusion of new well-designed studies and the exclusion of the low-quality ones have significantly improved the reliability of results, which may be useful to plan strategies for future research and diagnosis and to rationalize the therapeutic resources available. PMID:28243076

  15. The frequency of pre-core gene mutations in chronic hepatitis B infection: a study of Malaysian subjects.

    Science.gov (United States)

    Yap, S F; Wong, P W; Chen, Y C; Rosmawati, M

    2002-03-01

    A retrospective study was carried out to determine the frequency of the pre-core stop codon mutant virus in a group of chronic hepatitis B carriers: 81 cases were considered [33 hepatits B e antigen (HBe) positive and 48 HBe negative]. All of the HBe positive cases had detectable viral DNA by hybridization analysis; in the case of the HBe negative cases, one third had detectable viral DNA by hybridization analysis and two thirds had HBV DNA detectable by polymerase chain reaction (PCR) amplification. Pre-core stop codon mutant detection was carried out on all specimens using allele-specific oligonucleotide hybridization following PCR amplification of the target sequence. The pre-core mutant was detected in 13/33 (39.4%) of HBe positive cases and in 32/48 (66.7%) of HBe negative cases. Sequence analysis was carried out on 8 of the 16 HBe negative specimens that did not carry the pre-core mutant virus to determine the molecular basis for the HBe minus phenotype in these cases: the 1762/1764 TA paired mutation in the second AT rich region of the core promoter was detected in five cases; a start codon mutation was detected in one case. The predominant mutation resulting in the HBe minus phenotype in our isolates was the 1896A pre-core ("pre-core stop codon") mutation; other mutations responsible for the phenotype included the core promoter paired mutation and pre-core start codon mutation. In view of the high frequency of the pre-core mutant virus, sequence analysis was performed to determine the virus genotype on the basis of the nucleotide sequence of codon 15. The sequences of 21 wild type virus (14 HBe positive and 7 HBe negative cases) were examined: 15 were found to be codon 15 CCT variants (71.4%); the frequency in the HBe positive group was 12/14 (85.7%), while that in the HBe negative group was 3/7 (42.9%). The high frequency of the codon 15 CCT variant in association with the frequent occurrence of the pre-core mutant in our isolates concurs with the results

  16. MHC class I and class II phenotype, gene, and haplotype frequencies in Greeks using molecular typing data.

    Science.gov (United States)

    Papassavas, E C; Spyropoulou-Vlachou, M; Papassavas, A C; Schipper, R F; Doxiadis, I N; Stavropoulos-Giokas, C

    2000-06-01

    In the present study, DNA typing for HLA-A, C, B, DRB1, DRB3, DRB4, DRB5, DQA1, DQB1, and DPB1 was performed for 246 healthy, unrelated Greek volunteers of 20-59 years of age. Phenotype, genotype frequencies, Hardy-Weinberg equilibrium fit, and 3-locus haplotype frequencies for HLA-A, C, B, HLA-A, B, DRB1, HLA-DRB1, DQA1, DQB1, and HLA-DRB1, DQB1, DPB1 were calculated. Furthermore, linkage disequilibrium, deltas, relative deltas and p-values for significance of the deltas were defined. The population studied is in Hardy-Weinberg equilibrium, and many MHC haplotypes are in linkage disequilibrium. The most frequent specificities were HLA-A*02 (phenotype frequency = 44.3%) followed by HLA-A*24 (27.2%), HLA-B*51 (28.5%), HLA-B*18 (26.8%) and HLA-B*35 (26.4%) and HLA-Cw*04 (30.1%) and HLA-Cw*12 (26.8%). The most frequent MHC class II alleles were HLA-DRB1*1104 (34.1%), HLA-DQB1*0301 (54.5%) and HLA-DPB1*0401 with a phenotype frequency of 59.8%. The most prominent HLA-A, C, B haplotypes were HLA-A*24, Cw*04, B*35, and HLA-A*02, Cw*04, B*35, each of them observed in 21/246 individuals. The most frequent HLA-A, B, DRB1 haplotype was HLA-A*02, B*18, DRB1*1104 seen in 20/246 individuals, while the haplotype HLA-DRB1*1104, DQB1*0301, DPB1*0401 was found in 49/246 individuals. Finally, the haplotype DRB1*1104, DQA1*0501, DQB1*0301 was observed in 83/246 individuals. These results can be used for the estimation of the probability of finding a suitable haplotypically identical related or unrelated stem cell donor for patients of Greek ancestry. In addition, they can be used for HLA and disease association studies, genetic distance studies in the Balkan and Mediterranean area, paternity cases, and matching probability calculations for the optimal allocation of kidneys in Greece.

  17. Haplotype Frequency of G691S/S904S in the RET Proto-Onco-gene in Patients with Medullary Thyroid Carcinoma.

    Directory of Open Access Journals (Sweden)

    Sara Sheikholeslami

    2014-02-01

    Full Text Available Medullary thyroid carcinoma (MTC occurs in both sporadic (75% and hereditary (25% forms. The missense mutations of the REarranged during Transfection (RET proto-oncogene in MTC development have been well demonstrated. The aim of this study was to investigate frequency of G691S/S904S haplotype in MTC patients and their relatives.In this research 293 participants were studied, including 181 patients (102 female, 79 male and 112 their relatives (58 female, 54 male. Genomic DNA was extracted from peripheral blood leucocytes using the standard Salting Out/Proteinase K method. Nucleotide change detection was performed using PCR and direct DNA sequencing methods.According to DNA sequencing results, 159 individuals (104 patients, 55 relatives had both G691S (rs1799939 missense mutation in exon11 and S904S (rs1800863 synonymous mutation in exon 15 of RET proto-oncogene. The allele frequency of G691S/S904S haplotype was 21.15% in patients and 10.75% in their relatives.The obtained data showed the frequency of G691S/S904S RET gene haplotype among Iranian MTC patients and their relatives. The G691S and S904S nucleotide changes were in complete linkage disequilibrium, so the results were grouped together and referred to as G691S/S904S haplotype. Further analysis is need to demonstrate the association between this haplotype and MTC development.

  18. Frequency of the C34T mutation of the AMPD1 gene in world-class endurance athletes: does this mutation impair performance?

    Science.gov (United States)

    Rubio, Juan C; Martín, Miguel A; Rabadán, Manuel; Gómez-Gallego, Félix; San Juan, Alejandro F; Alonso, Juan M; Chicharro, José L; Pérez, Margarita; Arenas, Joaquín; Lucia, Alejandro

    2005-06-01

    The C34T mutation in the gene encoding for the skeletal muscle-specific isoform of AMP deaminase (AMPD1) is a common mutation among Caucasians (i.e., one of five individuals) that can impair exercise capacity. The purpose of this study was twofold. First, we determined the frequency distribution of the C34T mutation in a group of top-level Caucasian (Spanish) male endurance athletes (cyclists and runners, n = 104). This group was compared with randomly selected Caucasian (Spanish) healthy (asymptomatic) nonathletes (n = 100). The second aim of this study was to compare common laboratory indexes of endurance performance (maximal oxygen uptake or ventilatory thresholds) within the group of athletes depending on their C34T AMPD1 genotype. The frequency of the mutant T allele was lower (P 0.05) between athlete carriers or noncarriers of the C34T mutation (e.g., maximal oxygen uptake 72.3 +/- 4.6 vs. 73.5 +/- 5.9 ml.kg(-1).min(-1), respectively). In conclusion, although the frequency distribution of the mutant T allele of the AMPD1 genotype is lower in Caucasian elite endurance athletes than in controls, the C34T mutation does not significantly impair endurance performance once the elite-level status has been reached in sports.

  19. [Gene frequencies and heterozygosity of the AB0 and RH blood group alleles in the populations of two cities of the Donetsk region, Ukraine].

    Science.gov (United States)

    Mukhin, V N; Chinakh, D G; Avdeev, A V; Kuleba, V V; Afanas'ev, M V

    2003-04-01

    The frequencies of the AB0 and RH blood group alleles and heterozygosity indices were determined for the populations of two large industrial cities of Gorlovka and Mariupol. In the population of Gorlovka the gene frequencies were as follows: AB0*0 = 0.576, AB0*A = 0.266, AB0*B = 0.158, and RH*D = 0.592, in Mariupol the frequencies were AB0*0 = 0.584, AB0*A = 0.265, AB0*B = 0.151, and RH*D = 0.604. In Gorlovka the heterozygosity indices in respect to the AB0 and RH alleles were 0.572 and 0.483, respectively; in Mariupol, 0.566 and 0.478, respectively. There were no statistically significant differences between the two populations in respect to the genetic markers analyzed. However, the heterozygosity values obtained were more similar to the corresponding estimates for some populations of Russia, than for the total population of the Ukraine.

  20. Positive selection of deleterious alleles through interaction with a sex-ratio suppressor gene in African Buffalo: a plausible new mechanism for a high frequency anomaly.

    Science.gov (United States)

    van Hooft, Pim; Greyling, Ben J; Getz, Wayne M; van Helden, Paul D; Zwaan, Bas J; Bastos, Armanda D S

    2014-01-01

    Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer) population of Kruger National Park, through positive selection of these alleles that is ultimately driven by a sex-ratio suppressor. We have previously shown that one in four Kruger buffalo has a Y-chromosome profile that, despite being associated with low body condition, appears to impart a relative reproductive advantage, and which is stably maintained through a sex-ratio suppressor. Apparently, this sex-ratio suppressor prevents fertility reduction that generally accompanies sex-ratio distortion. We hypothesize that this body-condition-associated reproductive advantage increases the fitness of alleles that negatively affect male body condition, causing genome-wide positive selection of these alleles. To investigate this we genotyped 459 buffalo using 17 autosomal microsatellites. By correlating heterozygosity with body condition (heterozygosity-fitness correlations), we found that most microsatellites were associated with one of two gene types: one with elevated frequencies of deleterious alleles that have a negative effect on body condition, irrespective of sex; the other with elevated frequencies of sexually antagonistic alleles that are negative for male body condition but positive for female body condition. Positive selection and a direct association with a Y-chromosomal sex-ratio suppressor are indicated, respectively, by allele clines and by relatively high numbers of homozygous deleterious alleles among sex-ratio suppressor carriers. This study, which employs novel statistical techniques to analyse heterozygosity-fitness correlations, is the first to demonstrate the abundance of sexually-antagonistic genes in a natural mammal population. It also has important

  1. Positive Selection of Deleterious Alleles through Interaction with a Sex-Ratio Suppressor Gene in African Buffalo: A Plausible New Mechanism for a High Frequency Anomaly

    Science.gov (United States)

    van Hooft, Pim; Greyling, Ben J.; Getz, Wayne M.; van Helden, Paul D.; Zwaan, Bas J.; Bastos, Armanda D. S.

    2014-01-01

    Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer) population of Kruger National Park, through positive selection of these alleles that is ultimately driven by a sex-ratio suppressor. We have previously shown that one in four Kruger buffalo has a Y-chromosome profile that, despite being associated with low body condition, appears to impart a relative reproductive advantage, and which is stably maintained through a sex-ratio suppressor. Apparently, this sex-ratio suppressor prevents fertility reduction that generally accompanies sex-ratio distortion. We hypothesize that this body-condition-associated reproductive advantage increases the fitness of alleles that negatively affect male body condition, causing genome-wide positive selection of these alleles. To investigate this we genotyped 459 buffalo using 17 autosomal microsatellites. By correlating heterozygosity with body condition (heterozygosity-fitness correlations), we found that most microsatellites were associated with one of two gene types: one with elevated frequencies of deleterious alleles that have a negative effect on body condition, irrespective of sex; the other with elevated frequencies of sexually antagonistic alleles that are negative for male body condition but positive for female body condition. Positive selection and a direct association with a Y-chromosomal sex-ratio suppressor are indicated, respectively, by allele clines and by relatively high numbers of homozygous deleterious alleles among sex-ratio suppressor carriers. This study, which employs novel statistical techniques to analyse heterozygosity-fitness correlations, is the first to demonstrate the abundance of sexually-antagonistic genes in a natural mammal population. It also has important

  2. Positive selection of deleterious alleles through interaction with a sex-ratio suppressor gene in African Buffalo: a plausible new mechanism for a high frequency anomaly.

    Directory of Open Access Journals (Sweden)

    Pim van Hooft

    Full Text Available Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer population of Kruger National Park, through positive selection of these alleles that is ultimately driven by a sex-ratio suppressor. We have previously shown that one in four Kruger buffalo has a Y-chromosome profile that, despite being associated with low body condition, appears to impart a relative reproductive advantage, and which is stably maintained through a sex-ratio suppressor. Apparently, this sex-ratio suppressor prevents fertility reduction that generally accompanies sex-ratio distortion. We hypothesize that this body-condition-associated reproductive advantage increases the fitness of alleles that negatively affect male body condition, causing genome-wide positive selection of these alleles. To investigate this we genotyped 459 buffalo using 17 autosomal microsatellites. By correlating heterozygosity with body condition (heterozygosity-fitness correlations, we found that most microsatellites were associated with one of two gene types: one with elevated frequencies of deleterious alleles that have a negative effect on body condition, irrespective of sex; the other with elevated frequencies of sexually antagonistic alleles that are negative for male body condition but positive for female body condition. Positive selection and a direct association with a Y-chromosomal sex-ratio suppressor are indicated, respectively, by allele clines and by relatively high numbers of homozygous deleterious alleles among sex-ratio suppressor carriers. This study, which employs novel statistical techniques to analyse heterozygosity-fitness correlations, is the first to demonstrate the abundance of sexually-antagonistic genes in a natural mammal population. It also has

  3. Alpha-1 antitrypsin Pi*Z gene frequency and Pi*ZZ genotype numbers worldwide: an update

    Directory of Open Access Journals (Sweden)

    Blanco I

    2017-02-01

    Full Text Available Ignacio Blanco,1 Patricia Bueno,2 Isidro Diego,3 Sergio Pérez-Holanda,4 Francisco Casas-Maldonado,5 Cristina Esquinas,6 Marc Miravitlles6,7 1Alpha1-Antitrypsin Deficiency Spanish Registry (REDAAT, Fundación Respira, Spanish Society of Pneumology and Thoracic Surgery (SEPAR, Barcelona, 2Internal Medicine Department, County Hospital of Jarrio, 3Materials and Energy Department, School of Mining Engineering, Oviedo University, 4Surgical Department, University Central Hospital of Asturias (HUCA, Oviedo, Principality of Asturias, 5Pneumology Department, Complejo Hospitalario Universitario de Granada, Granada, 6Pneumology Department, Hospital Universitari Vall d’Hebron, 7CIBER de Enfermedades Respiratorias (CIBERES, Barcelona, Spain Abstract: In alpha-1 antitrypsin deficiency (AATD, the Z allele is present in 98% of cases with severe disease, and knowledge of the frequency of this allele is essential from a public health perspective. However, there is a remarkable lack of epidemiological data on AATD worldwide, and many of the data currently used are outdated. Therefore, the objective of this study was to update the knowledge of the frequency of the Z allele to achieve accurate estimates of the prevalence and number of Pi*ZZ genotypes worldwide based on studies performed according to the following criteria: 1 samples representative of the general population, 2 AAT phenotyping characterized by adequate methods, and 3 measurements performed using a coefficient of variation calculated from the sample size and 95% confidence intervals. Studies fulfilling these criteria were used to develop maps with an inverse distance weighted (IDW-interpolation method, providing numerical and graphical information of Pi*Z distribution worldwide. A total of 224 cohorts from 65 countries were included in the study. With the data provided by these cohorts, a total of 253,404 Pi*ZZ were estimated worldwide: 119,594 in Europe, 91,490 in America and Caribbean, 3,824 in

  4. High frequency of mutations in codon 98 of the peripheral myelin protein Po gene in 20 French CMT1 patients

    Energy Technology Data Exchange (ETDEWEB)

    Rougher, H.; LeGuern, E. Gouider, R. [and others

    1996-03-01

    Charcot-Marie-Tooth disease, characterized by distal muscle weakness and amyotrophy, decreased or absent tendon reflexes, and high arched feet, is the most common inherited peripheral neuropathy, with a prevalence of 1 in 2,500. Two types of CMT have been distinguished on the basis of nerve conduction velocities. CMT type 1 is the most frequent, with markedly slowed velocities ({<=}40 m/s) associated with hypertrophic onion bulb changes on nerve biopsy. Autosomal dominant CMT1 is genetically heterogeneous: CMT1A is caused by a 1.5-Mb duplication in 17p11.2 and, more rarely, by a point mutation in tha PMP22 (peripheral myelin protein, 22 kD) gene located in the duplicated region; CMT1B results from mutations in the Po (peripheral myelin protein zero) gene in 1q22-23. Forty-five percent (7/16) of the published mutations associated with CMT1 occur in exon 3 of Po. In order to determine the cause of CMT1 in 20 unrelated patients without 17p11.2 duplications, mutations were sought in exon 3 of Po with three techniques: nonradioactive SSCP, automated sequencing, and PCR enzymatic restriction. 18 refs., 2 figs.

  5. ama1 genes of sympatric Plasmodium vivax and P. falciparum from Venezuela differ significantly in genetic diversity and recombination frequency.

    Directory of Open Access Journals (Sweden)

    Rosalynn L Ord

    Full Text Available BACKGROUND: We present the first population genetic analysis of homologous loci from two sympatric human malaria parasite populations sharing the same human hosts, using full-length sequences of ama1 genes from Plasmodium vivax and P. falciparum collected in the Venezuelan Amazon. METHODOLOGY/PRINCIPAL FINDINGS: Significant differences between the two species were found in genetic diversity at the ama1 locus, with 18 distinct haplotypes identified among the 73 Pvama1 sequences obtained, compared to 6 unique haplotypes from 30 Pfama1 sequences, giving overall diversity estimates of h = 0.9091, and h = 0.538 respectively. Levels of recombination were also found to differ between the species, with P. falciparum exhibiting very little recombination across the 1.77 kb sequence. In contrast, analysis of patterns of nucleotide substitutions provided evidence that polymorphisms in the ama1 gene of both species are maintained by balancing selection, particularly in domain I. The two distinct population structures observed are unlikely to result from different selective forces acting upon the two species, which share both human and mosquito hosts in this setting. Rather, the highly structured P. falciparum population appears to be the result of a population bottleneck, while the much less structured P. vivax population is likely to be derived from an ancient pool of diversity, as reflected in a larger estimate of effective population size for this species. Greatly reduced mosquito transmission in 1997, due to low rainfall prior to the second survey, was associated with far fewer P. falciparum infections, but an increase in P. vivax infections, probably due to hypnozoite activation. CONCLUSIONS/SIGNIFICANCE: The relevance of these findings to putative competitive interactions between these two important human pathogen species is discussed. These results highlight the need for future control interventions to employ strategies targeting each of the parasite

  6. The frequency of A91V in the perforin gene and the effect of tumor necrosis factor-α promoter polymorphism on acquired hemophagocytic lymphohistiocytosis

    Directory of Open Access Journals (Sweden)

    Hamza Okur

    2011-06-01

    Full Text Available Objective: Numerous acquired etiological factors, such as infections, malignancies, and collagen tissue disorders, are involved in the development of acquired hemophagocytic lymphohistiocytosis (AHLH. Not everyone with the same etiological factors developments AHLH, which suggests the role of additional genetic or environmental predisposing factors that remain to be identified. Materials and Methods: Perforin gene A91V missense transition (C>T change at position 272 in exon 2 of the perforin gene and TNF-α gene promoter-1031 T>C nucleotide substitution are 2 candidate genetic predisposing factors due to their potential to alter inflammatory responses. In the present study these changes were investigated in healthy controls and AHLH patients.Results: A91V transition was observed in 7 of the 159 (4.4% controls. Among the 44 AHLH patients, 5 (11.3% were heterozygous and the difference in the frequency of A91V transition, although striking (odds ratio: 2.8, was not statistically significant (p=0.09. All A91V-positive patients had infection. TNF-α-1031 T>C polymorphism was examined in 164 healthy controls and 40 AHLH patients, and the CC risk-elevating genotype was noted in 7 (4.3% of the controls and 1 (2.5% of the AHLH patients. The frequency of C and T alleles was 22.5% (n=18 and 77.5% (n=62 among the AHLH patients, and 22% (n=72 and 78% (n=259 among the controls, respectively. There wasn’t a statistically significant difference between the groups in terms of allele frequencies (p>0.05.Conclusion: The present results indicate that compared to controls, A91V mutation was 2.8-fold more prevalent (according to the odds ratio in the AHLH patients. A91V mutation is not uncommon in the general population and increases the risk of AHLH in patients with an underlying condition, especially those with an underlying infection.

  7. The spectrum and frequency of self-inflicted and host gene mutations produced by the transposon Ac in maize.

    Science.gov (United States)

    Huang, Jun T; Dooner, Hugo K

    2012-10-01

    The autonomous transposon Activator (Ac) is a powerful mutagen. Ac-induced mutations range from small footprints of host sequences to large rearrangements of transposon or host sequences. These mutations arise by different repair mechanisms of the double-strand break produced by Ac excision: footprints by nonhomologous end joining and rearrangements by various mechanisms, including DNA replication repair. Footprints greatly outnumber other mutations, masking them because they usually share a nonfunctional phenotype. To determine the spectrum and frequencies of host and self-mutations generated by Ac, we used an allele harboring Ac in the 5' untranslated region bronze (bz). In this system, simple excisions produce purple revertants, whereas deletions of host or transposon sequences produce stable bronze (bz-s) mutants. Internal and terminal deletions of Ac predominated among the 72 bz-s derivatives. Most internal deletions (52 of 54) behaved as nonautonomous Dissociation (Ds) elements. All nine terminal deletions or fractured Ac (fAc) elements had rearrangements of adjacent host sequences. Most Ds and fAc deletion junctions displayed microhomologies and contained filler DNA from nearby sequences, suggesting an origin by DNA repair synthesis followed by microhomology-mediated end joining. All mutations occurred more frequently in pollen, where one in 200 grains carried new Ds or fAc elements.

  8. High frequency electromagnetic fields (GSM signals) affect gene expression levels in tumor suppressor p53-deficient embryonic stem cells.

    Science.gov (United States)

    Czyz, Jaroslaw; Guan, Kaomei; Zeng, Qinghua; Nikolova, Teodora; Meister, Armin; Schönborn, Frank; Schuderer, Jürgen; Kuster, Niels; Wobus, Anna M

    2004-05-01

    Effects of electromagnetic fields (EMF) simulating exposure to the Global System for Mobile Communications (GSM) signals were studied using pluripotent embryonic stem (ES) cells in vitro. Wild-type ES cells and ES cells deficient for the tumor suppressor p53 were exposed to pulse modulated EMF at 1.71 GHz, lower end of the uplink band of GSM 1800, under standardized and controlled conditions, and transcripts of regulatory genes were analyzed during in vitro differentiation. Two dominant GSM modulation schemes (GSM-217 and GSM-Talk), which generate temporal changes between GSM-Basic (active during talking phases) and GSM-DTX (active during listening phases thus simulating a typical conversation), were applied to the cells at and below the basic safety limits for local exposures as defined for the general public by the International Commission on Nonionizing Radiation Protection (ICNIRP). GSM-217 EMF induced a significant upregulation of mRNA levels of the heat shock protein, hsp70 of p53-deficient ES cells differentiating in vitro, paralleled by a low and transient increase of c-jun, c-myc, and p21 levels in p53-deficient, but not in wild-type cells. No responses were observed in either cell type after EMF exposure to GSM-Talk applied at similar slot-averaged specific absorption rates (SAR), but at lower time-averaged SAR values. Cardiac differentiation and cell cycle characteristics were not affected in embryonic stem and embryonic carcinoma cells after exposure to GSM-217 EMF signals. Our data indicate that the genetic background determines cellular responses to GSM modulated EMF. Bioelectromagnetics 25:296-307, 2004.

  9. Frequency of primary iron overload and HFE gene mutations (C282Y, H63D and S65C) in chronic liver disease patients in north India

    Institute of Scientific and Technical Information of China (English)

    Barjinderjit Kaur Dhillon; Reena Das; Gurjeewan Garewal; Yogesh Chawla; RK Dhiman; Ashim Das; Ajay Duseja; GR Chandak

    2007-01-01

    AIM: To identify the frequency of iron overload and study the three mutations in the HFE gene (C282Y,H63D, and S65C) in patients with chronic liver disorders (CLD) and controls.METHODS: To identify patients with iron overload (transferrin saturation > 45% in females and > 50% in males and serum ferritin > 1000 ng/mL) we evaluated 236 patients with CLD, including 59 with non-alcoholic steatohepatitis (NASH), 22 with alcoholic liver disease (ALD), 19 of cirrhosis due to viruses (HBV, HCV), and 136 with cryptogenic cirrhosis. Mutations of the HFE gene were analyzed by PCR-RE. hundred controls were screened for iron status and the mutations.RESULTS: Seventeen patients with CLD showed evidence of iron overload. Fifteen cases of iron overload had cryptogenic cirrhosis and two had ALD. None of the controls showed iron overload. We did not find any individual with 282Y or 65C either in the cases or in the controls. The prevalence of H63D heterozygosity was 12% in normal individuals, 14.8% in 236 patients (16.9% in NASH, 13.6% in ALD, 26.3% in viral and 12.5% in cryptogenic cirrhosis) and the overall prevalence was 13.98%. Only two of the 17 patients with primary iron overload were heterozygous for H63D. One patient with NASH and one normal individual who were homozygous for H63D showed no iron overload.CONCLUJSION: Primary iron overload in Indians is nonHFE type, which is different from that in Europeans and further molecular studies are required to determine the defect in various iron regulatory genes.

  10. Distribution of FcγR gene polymorphisms among two sympatric populations in Mali: differing allele frequencies, associations with malariometric indices and implications for genetic susceptibility to malaria.

    Science.gov (United States)

    Cherif, Mariama; Amoako-Sakyi, Daniel; Dolo, Amagana; Pearson, Jan-Olov; Gyan, Ben; Obiri-Yeboah, Dorcas; Nebie, Issa; Sirima, Sodiomon B; Doumbo, Ogobara; Troye-Blomberg, Marita; Bakary, Maiga

    2016-01-19

    Genetic polymorphisms in the complex gene cluster encoding human Fc-gamma receptors (FcγRs) may influence malaria susceptibility and pathogenesis. Studying genetic susceptibility to malaria is ideal among sympatric populations because the distribution of polymorphic genes among such populations can help in the identification malaria candidate genes. This study determined the distribution of three FcyRs single nucleotide polymorphisms (SNPs) (FcγRIIB-rs1050519, FcγRIIC-rs3933769 and FcγRIIIA-rs396991) among sympatric Fulani and Dogon children with uncomplicated malaria. The association of these SNPs with clinical, malariometric and immunological indices was also tested. This study involved 242 Fulani and Dogon volunteers from Mali age under 15 years. All SNPs were genotyped with predesigned TaqMan(®) SNP Genotyping Assays. Genotypic and allelic distribution of SNPs was compared across ethnic groups using the Fisher exact test. Variations in clinical, malariometric and immunologic indices between groups were tested with Kruskal-Wallis H, Mann-Whitney U test and Fisher exact test where appropriate. The study confirmed known malariometric and immunologic differences between sympatric Fulani and non-Fulani tribes. Parasite density was lower in the Fulani than the Dogon (p Dogon (p Dogon (p = 0.0043). The difference in the mutant allele frequency of FcγRIIB (rs1050519) between the two ethnic groups was however not statistically significant (p = 0.064). The mutant allele of rs396991 was associated with high malaria-specific IgG1 and IgG3 in the entire study population and Dogon tribe, p = 0.023 and 0.015, respectively. Parasite burden was lower in carriers of the FcγRIIC (rs3933769) mutant allele than non-carriers in the entire study population (p Dogon indirectly suggest that these SNPs may influence malaria susceptibility and pathogenesis in the study population. The high frequency of the FcγRIIC (rs3933769) mutant allele in the Fulani and its

  11. Gene

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes,...

  12. Gilbert's syndrome: High frequency of the (TA)7 TAA allele in India and its interaction with a novel CAT insertion in promoter of the gene for bilirubin UDP-glucuronosyltransferase 1 gene

    Institute of Scientific and Technical Information of China (English)

    Shabana Farheen; Sanghamitra Sengupta; Amal Santra; Suparna Pal; Gopal Krishna Dhali; Meenakshi Chakravorty; Partha P Majumder; Abhijit Chowdhury

    2006-01-01

    AIM: To identify the variants in UDP-glucuronosyltransferase 1 (UGT1A1) gene in Gilbert's syndrome (GS) and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India.METHODS: Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done byin silico analysis and by estimating UGT1A1 promoter activity carried out by luciferase reporter assay of appropriate constructs in Hep G2 cell line.RESULTS: Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide (CAT) insertion in the promoter found in a subset (10%) of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level.CONCLUSION: The genetic epidemiology of GS is variable across ethnic groups and the epistatic interactions among UGT1A1 promoter variants modulate bilirubin glucuronidation.

  13. The influence of genetic polymorphisms in XRCC3 and ADH5 genes on the frequency of genotoxicity biomarkers in workers exposed to formaldehyde.

    Science.gov (United States)

    Ladeira, Carina; Viegas, Susana; Carolino, Elisabete; Gomes, Manuel C; Brito, Miguel

    2013-04-01

    The International Agency for Research on Cancer classified formaldehyde as carcinogenic to humans because there is "sufficient epidemiological evidence that it causes nasopharyngeal cancer in humans". Genes involved in DNA repair and maintenance of genome integrity are critically involved in protecting against mutations that lead to cancer and/or inherited genetic disease. Association studies have recently provided evidence for a link between DNA repair polymorphisms and micronucleus (MN) induction. We used the cytokinesis-block micronucleus (CBMN assay) in peripheral lymphocytes and MN test in buccal cells to investigate the effects of XRCC3 Thr241Met, ADH5 Val309Ile, and Asp353Glu polymorphisms on the frequency of genotoxicity biomarkers in individuals occupationally exposed to formaldehyde (n = 54) and unexposed workers (n = 82). XRCC3 participates in DNA double-strand break/recombination repair, while ADH5 is an important component of cellular metabolism for the elimination of formaldehyde. Exposed workers had significantly higher frequencies (P < 0.01) than controls for all genotoxicity biomarkers evaluated in this study. Moreover, there were significant associations between XRCC3 genotypes and nuclear buds, namely XRCC3 Met/Met (OR = 3.975, CI 1.053-14.998, P = 0.042) and XRCC3 Thr/Met (OR = 5.632, CI 1.673-18.961, P = 0.005) in comparison with XRCC3 Thr/Thr. ADH5 polymorphisms did not show significant effects. This study highlights the importance of integrating genotoxicity biomarkers and genetic polymorphisms in human biomonitoring studies. Copyright © 2013 Wiley Periodicals, Inc.

  14. Genetic variation among the Mapuche Indians from the Patagonian region of Argentina: mitochondrial DNA sequence variation and allele frequencies of several nuclear genes.

    Science.gov (United States)

    Ginther, C; Corach, D; Penacino, G A; Rey, J A; Carnese, F R; Hutz, M H; Anderson, A; Just, J; Salzano, F M; King, M C

    1993-01-01

    DNA samples from 60 Mapuche Indians, representing 39 maternal lineages, were genetically characterized for (1) nucleotide sequences of the mtDNA control region; (2) presence or absence of a nine base duplication in mtDNA region V; (3) HLA loci DRB1 and DQA1; (4) variation at three nuclear genes with short tandem repeats; and (5) variation at the polymorphic marker D2S44. The genetic profile of the Mapuche population was compared to other Amerinds and to worldwide populations. Two highly polymorphic portions of the mtDNA control region, comprising 650 nucleotides, were amplified by the polymerase chain reaction (PCR) and directly sequenced. The 39 maternal lineages were defined by two or three generation families identified by the Mapuches. These 39 lineages included 19 different mtDNA sequences that could be grouped into four classes. The same classes of sequences appear in other Amerinds from North, Central, and South American populations separated by thousands of miles, suggesting that the origin of the mtDNA patterns predates the migration to the Americas. The mtDNA sequence similarity between Amerind populations suggests that the migration throughout the Americas occurred rapidly relative to the mtDNA mutation rate. HLA DRB1 alleles 1602 and 1402 were frequent among the Mapuches. These alleles also occur at high frequency among other Amerinds in North and South America, but not among Spanish, Chinese or African-American populations. The high frequency of these alleles throughout the Americas, and their specificity to the Americas, supports the hypothesis that Mapuches and other Amerind groups are closely related.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. High frequency of loss of allelic integrity at Wilms′ tumor suppressor gene-1 locus in advanced breast tumors associated with aggressiveness of the tumor

    Directory of Open Access Journals (Sweden)

    S Gupta

    2009-01-01

    Full Text Available Background: The product of Wilms′ tumor suppressor gene (WT1, a nuclear transcription factor, regulates the expression of the insulin-like growth factor (IGF and transforming growth factor (TGF systems, both of which are implicated in breast tumorigenesis and are known to facilitate angiogenesis. In the present study, WT1 allelic integrity was examined by Loss of Heterozygosity (LOH studies in infiltrating breast carcinoma (n=60, ductal carcinoma in situ (DCIS (n=10 and benign breast disease (n=5 patients, to determine its possible association with tumor progression. Methods: LOH at the WT1 locus (11p13 as determined by PCR-RFLP for Hinf1 restriction site and was subsequently examined for its association with intratumoral expression of various growth factors i.e. TGF-β1, IGF-II, IGF-1R and angiogenesis (VEGF and Intratumoral micro-vessel density in breast carcinoma. Results: Six of 22 (27.2% genetically heterozygous of infiltrating breast carcinoma and 1 of 4 DCIS cases showed loss of one allele at WT1 locus. Histologically, the tumors with LOH at WT1 were Intraductal carcinoma (IDC and were of grade II and III. There was no correlation in the appearance of LOH at WT1 locus with age, tumor stage, menopausal status, chemotherapy status and lymph node metastasis. The expression of factor IGF-II and its receptor, IGF-1R was significantly higher in carcinoma having LOH at WT1 locus. A positive correlation was observed between the TGF-β1, VEGF expression and IMD scores in infiltrating carcinoma. Conclusions: The current study indicates that the high frequency of loss of allelic integrity at Wilms′ tumor suppressor gene-1 locus in high-graded breast tumors is associated with aggressiveness of the tumor.

  16. Frequency of polymorphisms of genes coding for HIV-1 co-receptors CCR5 and CCR2 in a Brazilian population

    Directory of Open Access Journals (Sweden)

    Munerato Patrícia

    2003-01-01

    Full Text Available Entry of human immunodeficiency type 1 virus (HIV-1 into target cells requires both CD4and one of the chemokine receptors. Viruses predominantly use one, or occasionally both, of the major co-receptors CCR5 and CXCR4, although other receptors, including CCR2B and CCR3, function as minor co-receptors. A 32-nucleotide deletion (delta32 within the beta-chemokine receptor 5 gene (CCR5 has been described in subjects who remain uninfected despite extensive exposition to HIV-1. The heterozygous genotype delays disease progression. This allele is common among Caucasians, but has not been found in people of African or Asian ancestry. A more common transition involving a valine to isoleucine switch in transmembrane domain I of CCR2B (64I, with unknown functional consequences, was found to delay disease progression but not to reduce infection risk. As the Brazilian population consists of a mixture of several ethnic groups, we decided to examine the genotype frequency of these polymorphisms in this country. There were 11.5% CCR5 heterozygotes among the HIV-1 infected population and 12.5% among uninfected individuals, similar to data from North America and Western Europe. The prevalence of CCR2-64I homozygotes and heterozygotes was 0.06 and 15.2%, respectively, also similar to what is known for North America and Western Europe.

  17. Frequency of blaKHM-1, blaIMP-1,2 and blaSPM-1 genes in clinical isolates of metallo β-lactamase producing Pseudomonas aeruginosa in hospitalized burned patients in Ghotbeddin Shirazi Hospital

    National Research Council Canada - National Science Library

    S. RostamPour; AA. Gorzin; Gh. Motamedi

    2015-01-01

    ...: The aim of this study was to evaluate the frequency of blaIMP-1, blaIMP-2, blaSPM-1 and blaKHM-1 genes in clinical isolates of MBL producing Pseudomonas aeruginosa in hospitalized burned patients...

  18. Frequency of the ETV6-RUNX1, BCR-ABL1, TCF3-PBX1, and MLL-AFF1 fusion genes in Guatemalan pediatric acute lymphoblastic leukemia patients and their ethnic associations.

    Science.gov (United States)

    Carranza, Claudia; Granados, Lilian; Morales, Oneida; Jo, Wendy; Villagran, Swuanny; Tinti, Damaris; Villegas, Mauricio; Antillón, Federico; Torselli, Silvana; Silva, Gabriel

    2013-06-01

    Fusion genes involved in acute lymphoblastic leukemia (ALL) occur mostly due to genetic and environmental factors, and only a limited number of studies have reported any ethnic influence. This study assesses whether an ethnic influence has an effect on the frequency of any of the four fusion genes: BCR-ABL1, ETV6-RUNX1, TCF3-PBX1, and MLL-AFF1 found in ALL. To study this ethnic influence, mononuclear cells were obtained from bone marrow samples from 143 patients with ALL. We performed RNA extraction and reverse transcription, then assessed the quality of the cDNA by amplifying the ABL1 control gene, and finally evaluated the presence of the four transcripts by multiplex polymerase chain reaction. We found 10 patients who had the BCR-ABL1 fusion gene (7%); 3 patients (2%) were TCF3-PBX1 positive; and 6 patients (4.5%) were ETV6-RUNX1 positive. The incidence of this last fusion gene is quite low when compared to the values reported in most countries. The low incidence of the ETV6-RUNX1 fusion gene found in Guatemala matches the incidence rates that have been reported in Spain and Indian Romani. Since it is known that an ethnic resemblance exists among these three populations, as shown by ancestral marker studies, the ALL data suggests an ethnic influence on the occurrence and frequency of this particular fusion gene.

  19. Frequency of conjugative transfer of plasmid-encoded ISEcp1 - blaCTX-M-15 and aac(6'-lb-cr genes in Enterobacteriaceae at a tertiary care center in Lebanon - role of transferases

    Directory of Open Access Journals (Sweden)

    Araj George F

    2010-07-01

    Full Text Available Abstract Background The frequency of transfer of genes encoding resistance to antimicrobial agents was determined by conjugation in ESBL-producing and/or fluoroquinolone or aminoglycoside resistant Enterobacteriaceae clinical isolates at a tertiary care center in Lebanon. In addition, the role of tra genes encoding transferases in mediating conjugation was assessed. Methods Conjugation experiments were done on 53 ESBL-producing and/or fluoroquinolone resistant E. coli and K. pneumoniae and ESBL-producing S. sonnei isolates. Antimicrobial susceptibility testing on parent and transconjugant isolates, and PCR amplifications on plasmid extracts of the resistance-encoding genes: blaCTX-M-15 with the ISEcp1 insertion sequence, the aac(6'-lb-cr and qnrS genes, as well as tra encoding transferases genes were done. Random amplified polymorphic DNA (RAPD analysis was performed to demonstrate whether conjugative isolates are clonal and whether they are linked epidemiologically to a particular source. Results Antimicrobial susceptibility testing on transconjugants revealed that 26 out of 53 (49% ESBL-producing Enterobacteriaceae were able to transfer antimicrobial resistance to the recipients. Transfer of high-level resistance to the transconjugants encoded by the blaCTX-M-15 gene downstream the ISEcp1 insertion sequence against 3rd generation cephalosporins, and of low-level resistance against ciprofloxacin, and variable levels of resistance against aminoglycosides encoded by aac(6'-lb-cr gene, were observed in transconjugants. tra encoding transferase genes were detected exclusively in conjugative isolates. Conclusion In conclusion, the frequency of transfer of antimicrobial resistance in non clonal Enterobacteriaceae at the tertiary care center by conjugation was 49%. Conjugation occurred in isolates expressing the tra encoding transferase genes. Multiple conjugative strains harboring the plasmid encoded antimicrobial resistant genes were circulating in

  20. A model of sensitivity: 1,3-butadiene increases mutant frequencies and genomic damage in mice lacking a functional microsomal epoxide hydrolase gene.

    Science.gov (United States)

    Wickliffe, Jeffrey K; Ammenheuser, Marinel M; Salazar, James J; Abdel-Rahman, Sherif Z; Hastings-Smith, Darlene A; Postlethwait, Edward M; Lloyd, R Stephen; Ward, Jonathan B

    2003-01-01

    The specific role that polymorphisms in xenobiotic metabolizing enzymes play in modulating sensitivity to 1,3-butadiene (BD) genotoxicity has been relatively unexplored. The enzyme microsomal epoxide hydrolase (mEH) is important in detoxifying the mutagenic epoxides of BD (butadiene monoepoxide [BDO], butadiene diepoxide [BDO(2)]). Polymorphisms in the human mEH gene appear to affect the function of the enzyme. We exposed mice with normal mEH activity (WT) and knockout mice without mEH activity (KO) to 20 ppm BD (inhalation) or 30 mg/kg BDO(2) (intraperitoneal [IP] injection). We then compared Hprt mutant frequencies (MFs) among these groups. KO mice exposed to BD exhibited a significant (P damage in WT and KO mice (comet tail moment) following IP exposure to 3 mg/kg and 30 mg/kg BDO(2). KO mice exposed to 3 mg/kg exhibited significantly more DNA damage than controls (7.5-12.1-fold increase) and exposed WT mice (3 mg/kg; 4.8-fold increase). KO mice exposed to 30 mg/kg BDO(2) exhibited significantly more DNA damage than all other groups (2.3-27.9-fold increase). Correlation analysis indicated that a significant, positive relationship (r(2) = 0.92) exists between comet-measured damage and Hprt MFs. The lack of mEH activity increases the genetic sensitivity of mice exposed to BD and BDO(2). This model should facilitate a mechanistic understanding of the observed variation in human genetic sensitivity following exposure to BD.

  1. Relative frequencies of deletereo genes in populations of droshopila Melanogaster from Laguna Verde, Veracruz; Frecuencias relativas de genes deletereos en poblaciones de Drosophila melanogaster originarias de Laguna Verde, Veracruz

    Energy Technology Data Exchange (ETDEWEB)

    Salceda, V. M. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: vmss@nuclear.inin.mx

    2008-07-01

    In order to obtain data about the possible changes and/or damages that could cause the operation of the reactors of the nuclear power plant of Laguna Verde to the populations of drosophila Melanogaster that lives in the zone, one carried out one series of biannual collections (summer and winter) during the years 1991-1992 and 1996-1998 to obtain individuals of this species and to subject them to a battery of tests. The flies of this species that it was possible to capture were transported to the Biology Laboratory of the National Institute of Nuclear Research, where they were put under in individual form a series of you cross they allowed that us in the third generation to detect the presence of deletereo genes that following their viability were catalogued like normal, lethal or less lethal according to the methodology of Wallace. This way a total of 933 second chromosomes was analyzed to leave of them the relative frequencies were calculated of each one of the categories, for each sample station. The result of the applied statistical test indicates us that not significant difference exists among the populations and that the differences of having them must only to the environment changes something that usually happen in all the population. For what we can point out that the presence of the reactors does not seem to influence negatively in the behavior of the population that lives in the zone. (Author)

  2. Effects of Korean Red Ginseng and HAART on vif Gene in 10 Long-Term Slow Progressors over 20 Years: High Frequency of Deletions and G-to-A Hypermutation

    Directory of Open Access Journals (Sweden)

    Young Keol Cho

    2013-01-01

    Full Text Available To investigate if Korean red ginseng (KRG affects vif gene, we determined vif gene over 20 years in 10 long-term slowly progressing patients (LTSP who were treated with KRG alone and then KRG plus HAART. We also compared these data with those of 21 control patients who did not receive KRG. Control patient group harbored only one premature stop codon (PSC (0.9%, whereas the 10 LTSP revealed 78 defective genes (18.1% (P<0.001. The frequency of small in-frame deletions was found to be significantly higher in patients who received KRG alone (10.5% than 0% in the pre-KRG or control patients (P<0.01. Regarding HAART, vif genes containing PSCs were more frequently detected in patients receiving KRG plus HAART than patients receiving KRG alone or control patients (P<0.01. In conclusion, our current data suggest that the high frequency of deletions and PSC in the vif gene is associated with KRG intake and HAART, respectively.

  3. Rainfall-driven sex-ratio genes in African buffalo suggested by correlations between Y-chromosomal haplotype frequencies and foetal sex ratio

    NARCIS (Netherlands)

    Hooft, van W.F.; Prins, H.H.T.; Getz, W.M.; Jolles, A.E.; Wieren, van S.E.; Greyling, B.J.; Helden, P.D.; Bastos, A.D.S.

    2010-01-01

    Background - The Y-chromosomal diversity in the African buffalo (Syncerus caffer) population of Kruger National Park (KNP) is characterized by rainfall-driven haplotype frequency shifts between year cohorts. Stable Y-chromosomal polymorphism is difficult to reconcile with haplotype frequency variati

  4. Frequency standards

    CERN Document Server

    Riehle, Fritz

    2006-01-01

    Of all measurement units, frequency is the one that may be determined with the highest degree of accuracy. It equally allows precise measurements of other physical and technical quantities, whenever they can be measured in terms of frequency.This volume covers the central methods and techniques relevant for frequency standards developed in physics, electronics, quantum electronics, and statistics. After a review of the basic principles, the book looks at the realisation of commonly used components. It then continues with the description and characterisation of important frequency standards

  5. Frequency of iss and irp2 genes by PCR method in Escherichia coli isolated from poultry with colibacillosis in comparison with healthy chicken in poultry farms of Zabol, South East of Iran.

    Science.gov (United States)

    Sadeghi Bonjar, M S; Salari, S; Jahantigh, M; Rashki, A

    2017-03-01

    There is no special trait for differentiation of Avian Pathogenic Escherichia coli from Avian Fecal Escherichia coli. This investigation is aimed, as a case control study, to evaluate and compare the frequency of iss and irp2 in 43 AFEC strains and also 40 and 56 E. coli strains isolated from the liver and kidney of chickens with colibacillosis, respectively, farmed in Zabol, as a border region of Iran, by PCR. 86.9% and 37.2% of isolates collected from chickens with colibacillosis and feces samples obtained from healthy chickens were positive for iss gene, respectively (Piss and irp2 genes makes these two genes good markers to differentiate AFEC and APEC strains especially in Sistan region to improve colibacillosis control measurements.

  6. Rare, Low-Frequency, and Common Variants in the Protein-Coding Sequence of Biological Candidate Genes from GWASs Contribute to Risk of Rheumatoid Arthritis

    NARCIS (Netherlands)

    Diogo, Dorothee; Kurreeman, Fina; Stahl, Eli A.; Liao, Katherine P.; Gupta, Namrata; Greenberg, Jeffrey D.; Rivas, Manuel A.; Hickey, Brendan; Flannick, Jason; Thomson, Brian; Guiducci, Candace; Ripke, Stephan; Adzhubey, Ivan; Barton, Anne; Kremer, Joel M.; Alfredsson, Lars; Sunyaev, Shamil; Martin, Javier; Zhernakova, Alexandra; Bowes, John; Eyre, Steve; Siminovitch, Katherine A.; Gregersen, Peter K.; Worthington, Jane; Klareskog, Lars; Padyukov, Leonid; Raychaudhuri, Soumya; Plenge, Robert M.

    2013-01-01

    The extent to which variants in the protein-coding sequence of genes contribute to risk of rheumatoid arthritis (RA) is unknown. In this study, we addressed this issue by deep exon sequencing and large-scale genotyping of 25 biological candidate genes located within RA risk loci discovered by genome

  7. The Frequency of blaVIM, blaIMP, blaKPC and blaNDM Carbapenemase Genes in Clinical Isolates of Klebsiella Pneumoniae in Kermanshah Medical Centers

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    A Zare

    2015-11-01

    Full Text Available Background: Carbapenemase genes have been spread among strains of Klebsiella pneumoniae that make them resistant to carbapenems. Hence, the present study aimed to study the prevalence of carbapenmase genes within K. pneumoniae isolates in Kermanshah medical centers. Methods: Sixty isolates of K. pneumoniae were collected and identified using API kit. Then, antibiotic susceptibility of isolates was determined using a disk diffusion method. The carbapenems-resistant isolates were screened for carbapenemases production using the Modified Hodge Test (MHT. The carbapenemase genes of blaVIM, blaIMP, KPC and blaNDM were detected by PCR test . Results: Out of 60 isolates, 4 isolates were resistant to carbapenem antibiotics, but only one isolate was demonstrated to be positive for carbapenemases by MHT phenotypic testing. The gene of blaVIM was detected in three isolates by PCR, though other genes were not found in the isolates. Within the isolates, 6.67% and 100% were resistant to carbapenem and ampicillin, respectively. Conclusion: The study findings revealed that dissemination rate of carbapenemase genes was not reported to be high among isolates of K. pneumoniae in Kermanshah. Only blaVIM gene was probably more frequent than other tested genes. Since most isolates examined in this study were susceptible to carbapenem antibiotics, these antibiotics are still regarded as effective drugs against infections caused by K. pneumoniae.

  8. Effects of weak, low-frequency pulsed electromagnetic fields (BEMER type) on gene expression of human mesenchymal stem cells and chondrocytes: an in vitro study.

    Science.gov (United States)

    Walther, Markus; Mayer, Florian; Kafka, Wolf; Schütze, Norbert

    2007-01-01

    In vitro effects of electromagnetic fields appear to be related to the type of electromagnetic field applied. Previously, we showed that human osteoblasts display effects of BEMER type electromagnetic field (BTEMF) on gene regulation. Here, we analyze effects of BTEMF on gene expression in human mesenchymal stem cells and chondrocytes. Primary mesenchymal stem cells from bone marrow and the chondrocyte cell line C28I2 were stimulated 5 times at 12-h intervals for 8 min each with BTEMF. RNA from treated and control cells was analyzed for gene expression using the affymetrix chip HG-U133A. A limited number of regulated gene products from both cell types mainly affect cell metabolism and cell matrix structure. There was no increased expression of cancer-related genes. RT-PCR analysis of selected transcripts partly confirmed array data. Results indicate that BTEMF in human mesenchymal stem cells and chondrocytes provide the first indications to understanding therapeutic effects achieved with BTEMF stimulation.

  9. A Population Based Study of the Genetic Association between Catecholamine Gene Variants and Spontaneous Low-Frequency Fluctuations in Reaction Time

    NARCIS (Netherlands)

    Bastiaansen, Jojanneke A.; Cummins, Tarrant D. R.; Riese, Harriette; van Roon, Arie; Nolte, Ilja M.; Oldehinkel, Albertine J.; Bellgrove, Mark A.

    2015-01-01

    The catecholamines dopamine and noradrenaline have been implicated in spontaneous low-frequency fluctuations in reaction time, which are associated with attention deficit hyperactivity disorder (ADHD) and subclinical attentional problems. The molecular genetic substrates of these behavioral phenotyp

  10. Positive Selection of Deleterious Alleles through Interaction with a Sex-Ratio Suppressor Gene in African Buffalo: A Plausible New Mechanism for a High Frequency Anomaly

    NARCIS (Netherlands)

    Hooft, van W.F.; Greyling, B.J.; Getz, W.M.; Helden, P.D.; Zwaan, B.J.; Bastos, A.D.S.

    2015-01-01

    Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer)

  11. Frequency synthesiser

    NARCIS (Netherlands)

    Drago, Salvatore; Sebastiano, Fabio; Leenaerts, Dominicus Martinus Wilhelmus; Breems, Lucien Johannes; Nauta, Bram

    2016-01-01

    A low power frequency synthesiser circuit (30) for a radio transceiver, the synthesiser circuit comprising: a digital controlled oscillator configured to generate an output signal having a frequency controlled by an input digital control word (DCW); a feedback loop connected between an output and an

  12. Determination of the frequency of polymorphisms in genes related to the genome stability maintenance of the population residing at Monte Alegre, PA (Brazil) municipality; Determinacao da frequencia de polimorfismos em genes relacionados a manutencao da estabilidade do genoma na populacao residente no municipio de Monte Alegre, PA

    Energy Technology Data Exchange (ETDEWEB)

    Hozumi, Cristiny Gomes

    2010-07-01

    The human exposure to ionizing radiation coming from natural sources is an inherent feature of human life on earth, for man and all living things have always been exposed to these sources. Ionizing radiation is a known genotoxic agent which can affect the genomic stability and genes related to DNA repair may play a role when they have committed certain polymorphism. This study aimed to analyze the frequency of polymorphisms (SNPs) in genes of DNA repair and cell cycle control: hOGG1 (Ser326Cys), XRCC3 (Thr241 Met) and p53 (Arg72Pro) in saliva samples from a population located Monte Alegre, state of Para were collected in August 2008 and 40 samples of men and 46 samples of women, adding a total of 86 samples. By RFLP was determined the frequency of homozygous genotypes and / or heterozygous for polymorphic genes. The I)OGG1 gene was 5% of the allele 326Cys, XRCC3 gene found about 21 % of the allele 241 Met and p53 gene showed 40.8% of the 72Pro allele. And the genotype frequencies of individuals for the three genes were 91.04%, 88.06% and 59.7% for homozygous wild genotype, 5.97%, 11.94% and 22.39% for heterozygote genotype and 2,99%, zero and 17:91% for homozygous polymorphic hOGG1 genes respectively, XRCC3, p53. These values are similar to those found in previous studies. The influence of these polymorphisms, which are involved in DNA repair and consequent genotoxicity induced by radiation depends on dose and exposure factors such as smoking, which is statistically a factor in public health surveillance in the region. This study gathered information and molecular epidemiology in Monte Alegre, that help to characterization of local population. (author)

  13. Distribution and genotype frequency of the C1431T and pro12ala polymorphisms of the peroxisome proliferator activator receptor gamma gene in an Iranian population

    OpenAIRE

    Hassan Rooki; Monir-Sadat Haerian; Pedram Azimzadeh; Mahmoud Ebrahimi; Reza Mirhafez; Gordon Ferns; Majid Ghayour-Mobarhan; Mohammad-Reza Zali

    2013-01-01

    Background: Peroxisome proliferator activator receptor gamma (PPARγ) is a nuclear transcription factor regulating multiple genes involved in cell growth, differentiation, carbohydrate and lipid metabolism and energy production. Several genetic variations in the PPARγ gene have been identified to be associated with diabetes, obesity, dyslipidemia, insulin resistance, metabolic syndrome and coronary artery disease. The present study was designed to explore the distribution of two common single n...

  14. Molecular Analysis of Gene Frequencies of TEM, CTX-M and SHV in Beta-Lactam Antibiotic-Resistant Strains of E. Coli Isolated from Urinary Tract Infections in Yasuj Hospitals

    Directory of Open Access Journals (Sweden)

    R Mortezavi

    2014-06-01

    Full Text Available Background & aim: Urinary tract infections is one of the most common infectious diseases which many factors are involved, but bacteria such as E.coli is the most important agent of urinary tract infections. Antibiotic resistance as a major problem in the treatment and control of these infections is considered. The aim of this study was to determine the genes that cause resistance to beta-lactam family of antibiotics on E.coli isolated from urinary tract infections in Yasuj city. Methods: In the present Cross-sectional study which was conducted over a period of seven months in 2013, 123 samples of E.coli were collected from Yasuj hospitals for molecular analysis of TEM, SHV CTX-M genes, causing antibiotic resistance by (PCR method.Data were analyzed using SPSS statistical test. Results: PCR showed that the gene frequency of TEM (50.94%, SHV (47.16%, CTX-M-9 (35.84%, and CTX-M-10, (32.07% and the highest and lowest prevalent of genes were related to TEM and CTX-M10 in E.coli isolated from urinary tract infections respectively. Conclusion: According to the high prevalence of resistance to beta-lactam antibiotics, the current study showed that the noted genes play an important role in facilitating the spread of antimicrobial resistance in this region.

  15. Allele frequency of a 24 bp duplication in exon 10 of the CHIT1 gene in the general Korean population and in Korean patients with Gaucher disease.

    Science.gov (United States)

    Woo, Kyu Ha; Lee, Beom Hee; Heo, Sun Hee; Kim, Jae-Min; Kim, Gu-Hwan; Kim, Yoo-Mi; Kim, Ja Hye; Choi, In-Hee; Yang, Song Hyun; Yoo, Han-Wook

    2014-05-01

    Plasma chitotriosidase activity is used for diagnosis and monitoring of Gaucher disease. However, homozygous duplication of a 24 bp region in exon 10 of the chitotriosidase gene (CHIT1) abolishes enzyme activity, limiting its use as a biomarker in Gaucher disease. This study investigates the allele frequency of the 24 bp duplication, in both the general Korean population and in patients with Gaucher disease. Fifteen Korean patients with Gaucher disease and 231 Korean normal individuals were enrolled. Genotyping was performed to identify the 24 bp duplication in exon 10 of CHIT1 using DNA extracted from peripheral leukocytes or dried blood spots. Two patients with Gaucher disease (13.3%) had normal plasma chitotriosidase activity, and carried a homozygous 24 bp duplication of exon 10 of the CHIT1 gene. Nine patients were heterozygote carriers (60.0%). Of the normal 231 Korean individuals, heterozygous duplication was detected in 109 individuals (47.2%) and homozygous duplication in 75 (32.5%). The allele frequency was 56.1% (95% confidence interval, 49.4-62.7%). The frequency of the 24 bp duplication was remarkably high in both Korean patients with Gaucher disease and in the normal population, limiting the efficacy of chitotriosidase as a biomarker in Gaucher disease in Korea. New biomarkers are required that consider the genetic characteristics of different populations.

  16. Quantitative resistance affects the speed of frequency increase but not the diversity of the virulence alleles overcoming a major resistance gene to Leptosphaeria maculans in oilseed rape.

    Science.gov (United States)

    Delourme, R; Bousset, L; Ermel, M; Duffé, P; Besnard, A L; Marquer, B; Fudal, I; Linglin, J; Chadœuf, J; Brun, H

    2014-10-01

    Quantitative resistance mediated by multiple genetic factors has been shown to increase the potential for durability of major resistance genes. This was demonstrated in the Leptosphaeria maculans/Brassica napus pathosystem in a 5year recurrent selection field experiment on lines harboring the qualitative resistance gene Rlm6 combined or not with quantitative resistance. The quantitative resistance limited the size of the virulent isolate population. In this study we continued this recurrent selection experiment in the same way to examine whether the pathogen population could adapt and render the major gene ineffective in the longer term. The cultivars Eurol, with a susceptible background, and Darmor, with quantitative resistance, were used. We confirmed that the combination of qualitative and quantitative resistance is an effective approach for controlling the pathogen epidemics over time. This combination did not prevent isolates virulent against the major gene from amplifying in the long term but the quantitative resistance significantly delayed for 5years the loss of effectiveness of the qualitative resistance and disease severity was maintained at a low level on the genotype with both types of resistance after the fungus population had adapted to the major gene. We also showed that diversity of AvrLm6 virulence alleles was comparable in isolates recovered after the recurrent selection on lines carrying either the major gene alone or in combination with quantitative resistance: a single repeat-induced point mutation and deletion events were observed in both situations. Breeding varieties which combine qualitative and quantitative resistance can effectively contribute to disease control by increasing the potential for durability of major resistance genes.

  17. Low-frequency electromagnetic fields do not alter responses of inflammatory genes and proteins in human monocytes and immune cell lines

    NARCIS (Netherlands)

    Bouwens, M.; Kleijn, de S.; Cuppen, J.J.M.; Savelkoul, H.F.J.; Verburg-van Kemenade, B.M.L.

    2012-01-01

    The effects of low frequency electromagnetic fields (LF EMF) on human health are the subject of on-going research and serious public concern. These fields potentially elicit small effects that have been proposed to have consequences, either positive or negative, for biological systems. To reveal pot

  18. Positive Selection of Deleterious Alleles through Interaction with a Sex-Ratio Suppressor Gene in African Buffalo: A Plausible New Mechanism for a High Frequency Anomaly

    NARCIS (Netherlands)

    Hooft, van W.F.; Greyling, B.J.; Getz, W.M.; Helden, P.D.; Zwaan, B.J.; Bastos, A.D.S.

    2015-01-01

    Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer) populati

  19. Positive Selection of Deleterious Alleles through Interaction with a Sex-Ratio Suppressor Gene in African Buffalo: A Plausible New Mechanism for a High Frequency Anomaly

    NARCIS (Netherlands)

    Hooft, van W.F.; Greyling, B.J.; Getz, W.M.; Helden, van P.D.; Zwaan, B.J.; Bastos, A.D.S.

    2014-01-01

    Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer) populati

  20. Frequency of the toxic shock syndrome toxin-1 gene in methicillin-susceptible and -resistant Staphylococcus aureus isolates from teaching hospitals in Shiraz, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Motamedifar

    2015-02-01

    Full Text Available INTRODUCTION: Staphylococcus aureus produces a range of virulence factors such as toxic shock syndrome toxin-1. METHODS: In this cross-sectional study of 345 clinical S. aureus isolates, the presence of the tst gene was assessed by polymerase chain reaction (PCR. RESULTS: The study revealed 53/345 (15.4% isolates were positive for the tst gene. The tst gene was present in 18.1% of methicillin-susceptible S. aureus (MSSA isolates and 11.6% of methicillin-resistant S. aureus (MRSA isolates (p = 0.136. CONCLUSIONS: These results reveal the remarkable risk of S. aureus infections in hospitals, regardless of methicillin-resistance status.

  1. INFLUENCE OF ROOT EXUDATES AND BACTERIAL METABOLIC ACTIVITY ON APPARENT CONJUGAL GENE TRANSFER FREQUENCIES IN THE RHIZOSPHERE OF WATER GRASS (ECHINOCLORA CRUSGALLI)

    Science.gov (United States)

    The premise that genetic exchange is primarily localized in niches characterized by dense bacterial populations and high availability of growth substrates was tested by relating conjugal gene transfer of an RP4 derivative to availability of root exudates and bacterial metabolic a...

  2. Frequency of biocide-resistant genes and susceptibility to chlorhexidine in high-level mupirocin-resistant, methicillin-resistant Staphylococcus aureus (MuH MRSA).

    Science.gov (United States)

    Liu, Qingzhong; Zhao, Huanqiang; Han, Lizhong; Shu, Wen; Wu, Qiong; Ni, Yuxing

    2015-08-01

    The aim of this study was to determine the prevalence of biocide-resistant determinants and the susceptibility to chlorhexidine in high-level mupirocin-resistant, methicillin-resistant Staphylococcus aureus (MuH MRSA). Fifty-three MuH MRSA isolates were analyzed for plasmid-borne genes (qacA/B, smr, qacG, qacH, and qacJ) by polymerase chain reaction (PCR); for chromosome-mediated genes (norA, norB, norC, mepA, mdeA, sepA, and sdrM) by PCR and quantitative reverse transcription-PCR (qRT-PCR); and for susceptibility to chlorhexidine by MIC and minimum bactericidal concentration (MBC). Furthermore, disinfectant efficacy was tested in the presence of 3.0% bovine serum albumin (BSA) in MBC detection. The plasmid-borne genes qacA/B (83.0%) and smr (77.4%) and overexpressions of chromosome-mediated genes norA (49.0%) and norB (28.8%) were predominantly found in isolates studied, and 90.6% of the isolates revealed tolerance to chlorhexidine. In the presence of BSA, the average MBC of chlorhexidine for these isolates rose to 256 μg/mL. Altogether, our results suggest that surveillance of sensitivity to biocides among MuH MRSA isolates is essential for hospital infection control.

  3. Extremely low frequency electromagnetic field in combination with β-Lapachone up-regulates the genes of non-homologous end joining

    Directory of Open Access Journals (Sweden)

    Fatemeh Sanie-Jahromi

    2017-10-01

    Conclusion: In overall, combination of β-Lap, Mor and EMF leads to increased expression of NHEJ related gene expression. This effect may lead to decreased sensitivity of SH-SY5Y cells against β-Lap and can improve its neuroprotective property which might be hopeful for its clinical applications.

  4. Mutations in Genes Encoding Cardiac Ion Channels Previously Associated With Sudden Infant Death Syndrome (SIDS) Are Present With High Frequency in New Exome Data

    DEFF Research Database (Denmark)

    Andreasen, Charlotte Hartig; Refsgaard, Lena; Nielsen, Jonas B

    2013-01-01

    Sudden infant death syndrome (SIDS) is the leading cause of death in the first 6 months after birth in the industrialized world. The genetic contribution to SIDS has been investigated intensively and to date, 14 cardiac channelopathy genes have been associated with SIDS. Newly published data from...

  5. Evaluation of exotoxin A gene and frequency of polymerase chain reaction sensitivity in detection of pseudomonas aeruginosa isolated from burn patients

    Directory of Open Access Journals (Sweden)

    Rasoul Yousefi Mashouf

    2014-06-01

    Conclusion: Our results showed that sensitivity of PCR mediated ETA gene in detection of pseudomonas aeruginosa strains is considerable and this factor can be used as a good factor identifying of pseudomonas aeruginosa. It seems more studies with larger sample size is necessary in this area.

  6. Frequency of blaKHM-1, blaIMP-1,2 and blaSPM-1 genes in clinical isolates of metallo β-lactamase producing Pseudomonas aeruginosa in hospitalized burned patients in Ghotbeddin Shirazi Hospital

    Directory of Open Access Journals (Sweden)

    S. RostamPour

    2015-06-01

    Full Text Available Background: Metallo-β-lactamase (MBL producing Pseudomonas aeruginosa is an important gram negative opportunistic bacterium in hospitals which its increasing number is of clinicians’ concerns. Objective: The aim of this study was to evaluate the frequency of blaIMP-1, blaIMP-2, blaSPM-1 and blaKHM-1 genes in clinical isolates of MBL producing Pseudomonas aeruginosa in hospitalized burned patients in Ghotbeddin Shirazi Center. Methods: This cross-sectional study was conducted in 210 burn wound samples from 2012 to 2013. Sensitivity of confirmed Pseudomonas aeruginosa was examined for standard antimicrobial agents using disk diffusion method. Detection of MBL producing isolates was performed by the double disk synergy test (DDST and the desired genes were detected by PCR. Data were analyzed using Chi-square test. Findings: By the phenotypic methods, 42 isolates (20% were identified as Pseudomonas aeruginosa that were resistant to the most studied antibiotics including Carbapenem (100% and were only sensitive to Colicitin (100%. 26 isolates (61.9% were identified as MBL producing Pseudomonas aeruginosa. 9 isolates (34.61% carried the blaIMP-2 and blaKHM-1 genes. The blaIMP-1 and blaSPM-1 genes were not found in any of the isolates. Conclusion: With regards to the results, it is suggested to periodically study the reasons for antibiotic resistance in each center.

  7. Low-frequency nonsynonymous variants in FKBPL and ARPC1B genes are associated with breast cancer risk in Chinese women.

    Science.gov (United States)

    Zhou, Wen; Jiang, Yue; Zhu, Meng; Hang, Dong; Chen, Jiaping; Zhou, Jing; Dai, Juncheng; Ma, Hongxia; Hu, Zhibin; Jin, Guangfu; Sha, Jiahao; Shen, Hongbing

    2017-02-01

    Genome-wide association studies have reported more than 100 independent common loci associated with breast cancer risk. The contribution of low-frequency or rare variants to breast cancer susceptibility has not been well explored. Thus, we applied exome chip to genotype >200 000 low-frequency and rare variants in 1064 breast cancer cases and 1125 cancer-free controls and subsequently validated promising associations in another 1040 breast cancer cases and 1240 controls. We identified two low-frequency nonsynonymous variants at FKBPL (rs200847762, OR = 0.34, 95% CI = 0.20-0.57, P = 4.31 × 10(-5) ) and ARPC1B (rs1045012, OR = 0.56, 95% CI = 0.43-0.74, P = 4.30 × 10(-5) ) associated with breast cancer risk. In stratification analyses, we found that the protective effect of rs200847762 was stronger in ER-positive breast cancer (OR = 0.18, 95% CI = 0.06-0.42) than that in ER-negative one (OR = 0.59, 95% CI = 0.31-1.05). Our findings indicate that low-frequency variants may also contribute to breast cancer susceptibility and genetic variants in 6p21.33 and 7q22.1 are important in breast carcinogenesis. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Frequencies of two functionally significant SNPs and their haplotypes of organic anion transporting polypeptide 1B1 SLCO1B1 gene in six ethnic groups of Pakistani population

    Directory of Open Access Journals (Sweden)

    Tausif Ahmed Rajput

    2014-06-01

    Full Text Available Objective(s:Organic anion transporter polypeptide 1B1 (OATP1B1 encoded by solute carrier organic transporter 1B1 (SLCO1B1 gene; a transporter involved in the uptake of drugs and endogenous compounds is present in hepatocyte sinusoidal membrane. Aim of this study was to investigate the frequencies of functionally significant SNPs (388A>G and 521T>C and their haplotypes in 6 ethnic groups of Pakistani population through the development of rapid and efficient Tetra amplification refractory mutation system (T. ARMS genotyping assay. Materials and Methods: Frequencies of alleles, genotype, and haplotypes of two functionally significant Single nucleotide polymorphism in 180 healthy Pakistani subjects and distributions in six ethnic groups by using a single step T. ARMS genotyping assay. Results: The allelic frequency for 388A>G SNP was 50% in total Pakistani population with distributions of 9.7%, 15.1%, 19.4%, 16.1%, 18.3%, and 21.5% in Punjabi, Sindhi, Balouchi, Pathan, Kashmiri and Hazara/Baltistan groups respectively; and for 521T>C SNP it was 23.9% in total Pakistani population with distributions of 11.1%, 8.9%, 15.6%, 11.1%, 31.1% and 22.2% in Punjabi, Sindhi, Balouchi, Pathan, Kashmiri, and Hazara/Baltistan groups. Both functionally significant SNPs occurred in four major haplotypes with a frequency of 35.5% for 388A/521T (*1A, 40.5% for 388G/521T (*1B, 14.4% for 388A/521C (*5, and 9.4% for 388G/521C (*15 with varying distributions among six ethnic groups. Conclusion: The 388A>G and 521T>C genotypes and corresponding haplotypes are present at varying frequencies in various ethnic groups of Pakistani population. Pharmacokinetic and pharmacodynamic

  9. Acute promyelocytic leukaemia in patients originating in Latin America is associated with an increased frequency of the bcr1 subtype of the PML/RARalpha fusion gene.

    Science.gov (United States)

    Douer, Dan; Santillana, Sergio; Ramezani, Laleh; Samanez, Cesar; Slovak, Marilyn L; Lee, Ming S; Watkins, Kristy; Williams, Tony; Vallejos, Carlos

    2003-08-01

    The PML/RARalpha fusion gene in acute promyelocytic leukaemia (APL) has three subtypes based on the breakpoint site of the PML gene: long (bcr1), short (bcr3) and variable (bcr2) subtypes. The PML/RARalpha fusion protein is involved in the pathogenesis of APL and the breakpoint site of the PML gene might be associated with aetiological factor(s). Because APL is over-represented in patients that originate in Latin America (Latinos), we evaluated whether the distribution of the PML/RARalpha fusion mRNA in this population is different to that reported in non-Latinos. Among 52 APL patients (28 from Mexico and Central America diagnosed in Los Angeles and 24 from Peru, South America), bcr1, bcr2 and bcr3 expression was 75%, 10% and 15% respectively. However, bcr1 breakpoints were significantly higher compared with non-Latino patients (340/654, 52%) reported in four studies. Often bcr1 and bcr2 are reported together; 862 (60%) of 1429 non-Latino APL patients reported in nine studies were either bcr1 or bcr2, compared with 44 (85%) in our 52 Latino patients. This difference was also statistically significant when our patients were compared to each of the individual studies from USA and Europe, but not for a small series from China and Japan. These results suggest that the overrepresentation of APL among Latin American patients can be accounted for by an increase of a single subtype--bcr1, and the breakage sites in the PML gene may not be random but possibly influenced by genetic and/or environmental factor(s).

  10. A balanced t(5;17 (p15;q22-23 in chondroblastoma: frequency of the re-arrangement and analysis of the candidate genes

    Directory of Open Access Journals (Sweden)

    Wijers-Koster Pauline

    2009-11-01

    Full Text Available Abstract Background Chondroblastoma is a benign cartilaginous tumour of bone that predominantly affects the epiphysis of long bones in young males. No recurrent chromosomal re-arrangements have so far been observed. Methods: We identified an index case with a balanced translocation by Combined Binary Ratio-Fluorescent in situ Hybridisation (COBRA-FISH karyotyping followed by breakpoint FISH mapping and array-Comparative Genomic Hybridisation (aCGH. Candidate region re-arrangement and candidate gene expression were subsequently investigated by interphase FISH and immunohistochemistry in another 14 cases. Results A balanced t(5;17(p15;q22-23 was identified. In the index case, interphase FISH showed that the translocation was present only in mononucleated cells and was absent in the characteristic multinucleated giant cells. The t(5;17 translocation was not observed in the other cases studied. The breakpoint in 5p15 occurred close to the steroid reductase 5α1 (SRD5A1 gene. Expression of the protein was found in all cases tested. Similar expression was found for the sex steroid signalling-related molecules oestrogen receptor alpha and aromatase, while androgen receptors were only found in isolated cells in a few cases. The breakpoint in 17q22-23 was upstream of the carbonic anhydrase × (CA10 gene region and possibly involved gene-regulatory elements, which was indicated by the lack of CA10 protein expression in the index case. All other cases showed variable levels of CA10 expression, with low expression in three cases. Conclusion We report a novel t(5;17(p15;q22-23 translocation in chondroblastoma without involvement of any of the two chromosomal regions in other cases studied. Our results indicate that the characteristic multinucleated giant cells in chondroblastoma do not have the same clonal origin as the mononuclear population, as they do not harbour the same translocation. We therefore hypothesise that they might be either reactive or

  11. 基于小波高频系数基因芯片数据的特征提取%Wavelet high- frequency coefficients for feature extraction of gene microarray data

    Institute of Scientific and Technical Information of China (English)

    刘玉杰; 刘毅慧

    2011-01-01

    结合小波分析理论与支持向量机理论,构造分类器模型,将前列腺癌基因芯片数据分成癌症和正常两种.本文着重研究小波高频系数基因芯片数据的特征提取,并通过实验对比小波高频系数和低频系数特征提取对分类器性能的影响.其中haar小波3层分解提取高频系数,送入分类器分类后,得到的正确分类率为93.31%.db1小波4层分解提取低频系数,送入分类器分类后,得到的正确分类率为93.53%.小波低频系数特征提取分类效果总体上好于高频系数,分类器性能稳定.%In the paper, we use the wavelet analysis theory and the support vector machine theory to build a model which can classify the prostate cancer microarray data into cancer and normal classes. We mainly research the wavelet high - frequency coefficients for feature extraction of prostate cancer gene microarray data in contrast to the low coefficients. We extract haar wavelet high - frequency coefficients at level 3 and feed the high - frequency coefficients to the classification. The correct classification' rate is 93. 31%. We extract dbl wavelet low - frequency coefficients at level 4 and feed the low - frequency coefficients to the classification. The correct classification rate is 93. 53%. The wavelet low - frequency coefficients for feature extraction are better than high - frequency coefficients. The classification modle is very stable.

  12. Allele and genotype frequencies of the polymorphic cytochrome P450 genes (CYP1A1, CYP3A4, CYP3A5, CYP2C9 and CYP2C19) in the Jordanian population.

    Science.gov (United States)

    Yousef, Al-Motassem; Bulatova, Nailya R; Newman, William; Hakooz, Nancy; Ismail, Said; Qusa, Hisham; Zahran, Farah; Anwar Ababneh, Nidaa; Hasan, Farah; Zaloom, Imad; Khayat, Ghada; Al-Zmili, Rawan; Naffa, Randa; Al-Diab, Ola

    2012-10-01

    Drug metabolizing enzymes participate in the neutralizing of xenobiotics and biotransformation of drugs. Human cytochrome P450, particularly CYP1A1, CYP2C9, CYP2C19, CYP3A4 and CYP3A5, play an important role in drug metabolism. The genes encoding the CYP enzymes are polymorphic, and extensive data have shown that certain alleles confer reduced enzymatic function. The goal of this study was to determine the frequencies of important allelic variants of CYP1A1, CYP2C9, CYP2C19, CYP3A4 and CYP3A5 in the Jordanian population and compare them with the frequency in other ethnic groups. Genotyping of CYP1A1(m1 and m2), CYP2C9 (2 and 3), CYP2C19 (2 and 3), CYP3A4 5, CYP3A5 (3 and 6), was carried out on Jordanian subjects. Different variants allele were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). CYP1A1 allele frequencies in 290 subjects were 0.764 for CYP1A1 1, 0.165 for CYP1A1 2A and 0.071 for CYP1A1 2C. CYP2C9 allele frequencies in 263 subjects were 0.797 for CYP2C9 1, 0.135 for CYP2C9 2 and 0.068 for CYP2C9 3. For CYP2C19, the frequencies of the wild type (CYP2C19 1) and the nonfunctional (2 and 3) alleles were 0.877, 0.123 and 0, respectively. Five subjects (3.16 %) were homozygous for 2/2. Regarding CYP3A4 1B, only 12 subjects out of 173 subjects (6.9 %) were heterozygote with none were mutant for this polymorphism. With respect to CYP3A5, 229 were analyzed, frequencies of CYP3A5 1, 3 and 6 were 0.071, 0.925 and 0.0022, respectively. Comparing our data with that obtained in several Caucasian, African-American and Asian populations, Jordanians are most similar to Caucasians with regard to allelic frequencies of the tested variants of CYP1A1, CYP2C9, CYP2C19, CYP3A4 and CYP3A5.

  13. Vestibular function is associated with residual low-frequency hearing loss in patients with bi-allelic mutations in the SLC26A4 gene.

    Science.gov (United States)

    Jung, Jinsei; Seo, Young Wook; Choi, Jae Young; Kim, Sung Huhn

    2016-05-01

    DFNB4 is non-syndromic, autosomal recessive type of hearing loss with an enlarged vestibular aqueduct (EVA) caused by mutations in SLC26A4/pendrin. Although the characteristics of hearing loss are well known in DFNB4, vestibular function remains inconclusive. We evaluated the vestibular function of 31 patients with bi-allelic mutations in SLC26A4/pendrin and analyzed genetic, radiological, and audiological correlations with vestibular function. In a caloric test, unilateral and bilateral vestibulopathies were detected in 45.2% and 6.4% of patients, respectively; however, only 22.6% had subjective vertigo symptoms. While vestibular phenotype was not significantly associated with specific mutations in genetic alleles or the sizes of the endolymphatic sac and vestibular aqueduct, a residual hearing threshold at a low frequency (500 Hz) was definitely correlated with vestibular function in DFNB4 (p = 0.005). These findings may indicate that vestibular function in DFNB4 deteriorates unilaterally in ears when hearing loss occurs. In conclusion, DFNB4 shows vestibular dysfunction, which is strongly linked to hearing loss at low frequencies without any allelic or anatomical predisposing factor.

  14. [Dose-Response Dependences for Frequency of RET/PTC Gene Rearrangements in Papillary Thyroid Carcinoma after Irradiation. Simple Pooling Analysis of Molecular Epidemiological Data].

    Science.gov (United States)

    Koterov, A N; Ushenkova, L N; Biryukov, A P

    2016-01-01

    On the basis of all possible publications on the theme included in the previously formed base of sources on molecular epidemiology of RET/PTC rearrangements in thyroid papillary carcinoma a pooled analysis ("simple pooling data") on determination of the dose-effect dependences for RET/PTC frequency in radiogenic carcinomas of various irradiated groups was performed. (They are groups subjected to radiotherapeutic exposure, residents near the Chernobyl nuclear power plant (CNPP) and victims of nuclear bombing). The tendency to Pearson linear correlation (r = 0.746; p = 0.148) between the frequency of RET/PTC and the estimated dose on thyroid in the regions affected by the CNPP accident was revealed. But this tendency was recognized to be random owing to abnormally low values of the indicator for the most contaminated Gomel region. The method tentatively called "case-control" showed reliable differences in thyroid dose values for carcinomas with RET/PTC and without those. The versatility of changes was found: the lack of RET/PTC for radiotherapeutic impacts was associated with higher doses, whereas in case of the CNPP accident and for nuclear bombing victims it was the opposite. Probably, in the first case the "cellular cleaning" phenomenon after exposure to very high doses took place. Search of direct Pearson correlations between average/median thyroid doses on groups and RET/PTC frequency in carcinomas of these groups showed a high reliability for the dose-effect dependences- at the continuous dose scale (for RET/PTC in total and RET/PTC1 respectively: r = 0.830; p = 0.002 and r = 0.906; p = 0.0003); while there was no significant correlation received for RET/PTC3. When using the weighting least square regression analysis (proceeding from the number of carcinomas in samples), the specified regularities remained. Attempts to influence the strength of correlation by exception ofthe data of all the samples connected with the accident on the CNPP did not significantly

  15. Characterization of Rotavirus Strains in a Danish Population: High Frequency of Mixed Infections and Diversity within the VP4 Gene of P[8] Strains

    DEFF Research Database (Denmark)

    Fischer, Torge; Eugen-Olsen, J; Pedersen, Anne Grethe Julius

    2005-01-01

    more than 20 different G-P combinations were identified, only 52% represented the globally most common types G1P[8], G2P[4], and G4P[8]. The G9 genotype, which is emerging worldwide, was identified in 12% of all samples. Twenty-one percent of the samples were of mixed genotypic origin, which...... is the highest frequency reported in any European population. The standard reverse transcription-PCR methods initially failed to identify a considerable fraction of the rotavirus P strains due to mutations at the VP4 primer-binding sites of P[8] strains. The application of a degenerate P[8] primer resulted...... for rotavirus vaccine implementation in a European population and underscore the importance of extensive strain surveillance prior to, during, and after introduction of any vaccine candidate....

  16. 广州地区汉族人群血小板抗原基因多态性及频率分布%Gene frequencies and genetic polymorphism of human platelet antigen in Guangzhou Han population

    Institute of Scientific and Technical Information of China (English)

    陈扬凯; 叶欣; 夏文杰; 丁浩强; 徐秀章; 邓晶; 邵媛; 王嘉励; 付涌水

    2015-01-01

    Objective To investigate the gene frequencies of human platelet antigen (HPA)-7Hita and HPA-12,-18,-19,-20,-21 in Guangzhou Han population.Methods A total of 95 blood donors were randomly selected into this study from voluntary blood donors in Guangzhou from September 2010 to September 2011,via systematic random sampling method.All these blood donors were health and qualified.Blood samples of the 95 blood donors were collected.Polymerase chain reaction-sequence specific primer (PCR-SSP) and multiple polymerase chain reaction-sequence specific primer (multi-PCR-SSP) were used to detected genotypes of HPA-7Hita,-12,-18,-19,-20,-21.Gene frequencies of HPA-7Hita and HPA-12bw、-18bw、-19bw、-20bw、-21bw were compared among different countries and areas.Results ① For these 95 blood donors in Guangzhou Han population,gene frequencies of HPA-7a、-12a、-18a、-19a、-20a、-21a were all 100%.No HPA-7Hita and HPA-12bw、-18bw、-19bw、-20bw、-21bw allele were found.②Further investigation revealed that gene frequency of HPA-7Hita in Guangzhou Han population was significantly lower than that in Japan population(P<0.05).Gene frequency of HPA-12bw was also significantly lower than that in German population(P<0.05).Gene frequencies of HPA-18bw,-19bw,-20bw,-21bw were the same as these in France,Brazil,China and Japan.Conclusions This study gained preliminary datas on gene frequencies of HPA-7Hita and HPA-12,-18,-19,-20,-21 in Guangzhou Han population,and provide experimental data and detection method for diagnosis,treatment and prognosis of clinical related diseases.%目的 探讨广州地区汉族人群人类血小板抗原(HPA)-7Hita及HPA-12,-18,-19,-20,-21等位基因多态性及其频率分布情况.方法 选取2010年9月至2011年9月于广州血液中心参与志愿无偿献血,且符合《献血者健康要求(GB18467-2001)》的广州地区汉族献血者中,采用系统随机抽样方法随机选择95例献血者作为研

  17. Tripartite ATP-independent periplasmic transporters: application of a relational database for genome-wide analysis of transporter gene frequency and organization.

    Science.gov (United States)

    Mulligan, Christopher; Kelly, David J; Thomas, Gavin H

    2007-01-01

    Tripartite ATP-independent periplasmic (TRAP) transporters are a family of extracytoplasmic solute receptor-dependent secondary transporters that are widespread in the prokaryotic world but which have not been extensively studied. Here, we present results of a genome-wide analysis of TRAP sequences and genome organization from application of TRAPDb, a relational database created for the collection, curation and analysis of TRAP sequences. This has revealed a specific enrichment in the number of TRAP transporters in several bacteria which is consistent with increased use of TRAP transporters in saline environments. Additionally, we report a number of new organizations of TRAP transporter genes and proteins which suggest the recruitment of TRAP transporter components for use in other biological contexts.

  18. A novel allelic variant of the human TSG-6 gene encoding an amino acid difference in the CUB module. Chromosomal localization, frequency analysis, modeling, and expression.

    Science.gov (United States)

    Nentwich, Hilke A; Mustafa, Zehra; Rugg, Marilyn S; Marsden, Brian D; Cordell, Martin R; Mahoney, David J; Jenkins, Suzanne C; Dowling, Barbara; Fries, Erik; Milner, Caroline M; Loughlin, John; Day, Anthony J

    2002-05-03

    Tumor necrosis factor-stimulated gene-6 (TSG-6) encodes a 35-kDa protein, which is comprised of contiguous Link and CUB modules. TSG-6 protein has been detected in the articular joints of osteoarthritis (OA) patients, with little or no constitutive expression in normal adult tissues. It interacts with components of cartilage matrix (e.g. hyaluronan and aggrecan) and thus may be involved in extracellular remodeling during joint disease. In addition, TSG-6 has been found to have anti-inflammatory properties in models of acute and chronic inflammation. Here we have mapped the human TSG-6 gene to 2q23.3, a region of chromosome 2 linked with OA. A single nucleotide polymorphism was identified that involves a non-synonymous G --> A transition at nucleotide 431 of the TSG-6 coding sequence, resulting in an Arg to Gln alteration in the CUB module (at residue 144 in the preprotein). Molecular modeling of the CUB domain indicated that this amino acid change might lead to functional differences. Typing of 400 OA cases and 400 controls revealed that the A(431) variant identified here is the major TSG-6 allele in Caucasians (with over 75% being A(431) homozygotes) but that this polymorphism is not a marker for OA susceptibility in the patients we have studied. Expression of the Arg(144) and Gln(144) allotypes in Drosophila Schneider 2 cells, and functional characterization, showed that there were no significant differences in the ability of these full-length proteins to bind hyaluronan or form a stable complex with inter-alpha-inhibitor.

  19. Molecular profiling of gene copy number abnormalities in key regulatory genes in high-risk B-lineage acute lymphoblastic leukemia: frequency and their association with clinicopathological findings in Indian patients.

    Science.gov (United States)

    Bhandari, Prerana; Ahmad, Firoz; Das, Bibhu Ranjan

    2017-05-01

    Genes related to key cellular pathways are frequently altered in B cell ALL and are associated with poor survival especially in high-risk (HR) subgroups. We examined gene copy number abnormalities (CNA) in 101 Indian HR B cell ALL patients and their correlation with clinicopathological features by multiplex ligation-dependent probe amplification. Overall, CNA were detected in 59 (59%) cases, with 26, 10 and 23% of cases harboring 1, 2 or +3 CNA. CNA were more prevalent in BCR-ABL1 (60%), pediatric (64%) and high WCC (WBC count) (63%) patients. Frequent genes deletions included CDNK2A/B (26%), IKZF1 (25%), PAX5 (14%), JAK2 (7%), BTG1 (6%), RB1 (5%), EBF1 (4%), ETV6 (4%), while PAR1 region genes were predominantly duplicated (20%). EBF1 deletions selectively associated with adults, IKZF1 deletions occurred frequently in high WCC and BCR-ABL1 cases, while PAR1 region gains significantly associated with MLL-AF4 cases. IKZF1 haploinsufficiency group was predominant, especially in adults (65%), high WCC (60%) patients and BCR-ABL1-negative (78%) patients. Most cases harbored multiple concurrent CNA, with IKZF1 concomitantly occurring with CDNK2A/B, PAX5 and BTG1, while JAK2 occurred with CDNK2A/B and PAX5. Mutually exclusive CNA included ETV6 and IKZF1/RB1, and EBF1 and JAK2. Our results corroborate with global reports, aggregating molecular markers in Indian HR B-ALL cases. Integration of CNA data from rapid methods like MLPA, onto background of existing gold-standard methods detecting significant chromosomal abnormalities, provides a comprehensive genetic profile in B-ALL.

  20. High frequency of the c.3207CA (p.H1069Q) mutation in A TP7B gene of Lithuanian patients with hepatic presentation of Wilson's disease

    Institute of Scientific and Technical Information of China (English)

    Laimutis Kucinskas; Jolanta Jeroch; Astra Vitkauskiene; Raimundas Sakalauskas; Vitalija Petrenkiene; Vaidutis Kucinskas; Rima Naginiene; Hartmut Schmidt; Limas Kupcinskas

    2008-01-01

    AIM: To investigate the prevalence of the ATP7B gene mutation in patients with hepatic presentation of Wilson's disease (WD) in Lithuania.METHODS: Eleven unrelated Lithuanian families, including 13 WD patients were tested. Clinically WD diagnosis was established in accordance to the Leipzig scoring system. Genomic DNA was extracted from whole venous blood using a salt precipitation method. Firstly, the semi-nested polymerase chain reaction (PCR) technique was used to detect the c.3207CA (p.H1069Q) mutation. Patients not homozygous for the c.3207CA (p.H1069Q) mutation were further analyzed. The 21 exons of the WD gene were amplified in a thermal cycler (Biometra T3 Thermocycler, G6ttingen, Germany). Direct sequencing of the amplified PCR products was performed by cycle sequencing using fluorescent dye terminators in an automatic sequencer (Applied Biosystems, Darmstadt, Germany).RESULTS: Total of 13 WD patients (mean age 26.4 years; range 17-40; male/female 3/10) presented with hepatic disorders and 16 their first degree relatives (including 12 siblings) were studied. Some of WD patients, in addition to hepatic symptoms, have had extrahepatic disorders (hemolytic anemia 3; Fanconi syndrome 1; neurophsychiatric and behavioural disorder 2). Liver biopsy specimens were available in all of 13 WD patients (8 had cirrhosis; 1-chronic hepatitis; 3-acute liver failure, l-liver steatosis). Twelve of 13 (92.3%) WD patients had the c.3207CA (p.H1069Q) mutation, 6 of them in both chromosomes, 6 were presented as compound heterozygotes with additional c.3472-82delGGTTTAACCAT, c.3402delC, c.3121CT (p.R1041W) or unknown mutations. For one patient with liver cirrhosis and psychiatric disorder (Leipzig score 6), no mutations were found. Out of 16 first degree WD relatives, 11 (68.7%) were heterozygous for the c.3207CA (p.H1069Q) mutation. Two patients with fulminant WD died from acute liver failure and 11 are in full remission under penicillamine or zinc acetate treatment. Three

  1. Vacuolar invertase gene silencing in potato (Solanum tuberosum L.) improves processing quality by decreasing the frequency of sugar-end defects.

    Science.gov (United States)

    Zhu, Xiaobiao; Richael, Craig; Chamberlain, Patrick; Busse, James S; Bussan, Alvin J; Jiang, Jiming; Bethke, Paul C

    2014-01-01

    Sugar-end defect is a tuber quality disorder and persistent problem for the French fry processing industry that causes unacceptable darkening of one end of French fries. This defect appears when environmental stress during tuber growth increases post-harvest vacuolar acid invertase activity at one end of the tuber. Reducing sugars produced by invertase form dark-colored Maillard reaction products during frying. Acrylamide is another Maillard reaction product formed from reducing sugars and acrylamide consumption has raised health concerns worldwide. Vacuolar invertase gene (VInv) expression was suppressed in cultivars Russet Burbank and Ranger Russet using RNA interference to determine if this approach could control sugar-end defect formation. Acid invertase activity and reducing sugar content decreased at both ends of tubers. Sugar-end defects and acrylamide in fried potato strips were strongly reduced in multiple transgenic potato lines. Thus vacuolar invertase silencing can minimize a long-standing French fry quality problem while providing consumers with attractive products that reduce health concerns related to dietary acrylamide.

  2. Vacuolar invertase gene silencing in potato (Solanum tuberosum L. improves processing quality by decreasing the frequency of sugar-end defects.

    Directory of Open Access Journals (Sweden)

    Xiaobiao Zhu

    Full Text Available Sugar-end defect is a tuber quality disorder and persistent problem for the French fry processing industry that causes unacceptable darkening of one end of French fries. This defect appears when environmental stress during tuber growth increases post-harvest vacuolar acid invertase activity at one end of the tuber. Reducing sugars produced by invertase form dark-colored Maillard reaction products during frying. Acrylamide is another Maillard reaction product formed from reducing sugars and acrylamide consumption has raised health concerns worldwide. Vacuolar invertase gene (VInv expression was suppressed in cultivars Russet Burbank and Ranger Russet using RNA interference to determine if this approach could control sugar-end defect formation. Acid invertase activity and reducing sugar content decreased at both ends of tubers. Sugar-end defects and acrylamide in fried potato strips were strongly reduced in multiple transgenic potato lines. Thus vacuolar invertase silencing can minimize a long-standing French fry quality problem while providing consumers with attractive products that reduce health concerns related to dietary acrylamide.

  3. Correlation of Frequency of Pseudomonas Aeruginosa and Exos & Exou Genes and Their Antibiotic Sensitivity Pattern in Specimen Isolated from ICU Ward

    Directory of Open Access Journals (Sweden)

    Mahsa Joodzadeh

    2016-06-01

    Full Text Available Pseudomonas aeruginosa is a cause of nosocomial infections that can be destroyer by antibiotic-resistant strains. This study conducted to determine the antibiotic susceptibility pattern and distribution of exoU and exoS among clinical isolates of P. aeruginosa. Fifty three specimens of tracheal tube were collected from patients who were hospitalized in ICU wards and P. aeruginosa were isolated and identified by phenotypic and molecular methods. Antibiotic resistance performs by disk diffusion and analyzed their virulence factors genes by PCR method. Susceptibility pattern of 53 isolates of P. aeruginosa showed that majority and minority of resistance belong to cefepime (55.4%,and Meropenem (50% Respectively. Twenty four (45.2% isolates were not susceptible to three or more different groups of antibiotics. Forty (71.4% of isolated have had exoSand1(1.8% exoU, 8(15%both of exoS and exoU and the rest being negative for exoS or exoU. Distribution of MDR(resistance to three or more group of antibiotics exoenzymes were shown: exoU(7.5%and exoS(90.5%. According to statistically analysis there were not significant relationship between presence of exo SandexoU and antibiotic resistance.

  4. DNA fusion-gene vaccination in patients with prostate cancer induces high-frequency CD8(+) T-cell responses and increases PSA doubling time.

    Science.gov (United States)

    Chudley, Lindsey; McCann, Katy; Mander, Ann; Tjelle, Torunn; Campos-Perez, Juan; Godeseth, Rosemary; Creak, Antonia; Dobbyn, James; Johnson, Bernadette; Bass, Paul; Heath, Catherine; Kerr, Paul; Mathiesen, Iacob; Dearnaley, David; Stevenson, Freda; Ottensmeier, Christian

    2012-11-01

    We report on the immunogenicity and clinical effects in a phase I/II dose escalation trial of a DNA fusion vaccine in patients with prostate cancer. The vaccine encodes a domain (DOM) from fragment C of tetanus toxin linked to an HLA-A2-binding epitope from prostate-specific membrane antigen (PSMA), PSMA(27-35). We evaluated the effect of intramuscular vaccination without or with electroporation (EP) on vaccine potency. Thirty-two HLA-A2(+) patients were vaccinated and monitored for immune and clinical responses for a follow-up period of 72 weeks. At week 24, cross-over to the immunologically more effective delivery modality was permitted; this was shown to be with EP based on early antibody data, and subsequently, 13/15 patients crossed to the +EP arm. Thirty-two HLA-A2(-) control patients were assessed for time to next treatment and overall survival. Vaccination was safe and well tolerated. The vaccine induced DOM-specific CD4(+) and PSMA(27)-specific CD8(+) T cells, which were detectable at significant levels above baseline at the end of the study (p = 0.0223 and p = 0.00248, respectively). Of 30 patients, 29 had a measurable CD4(+) T-cell response and PSMA(27)-specific CD8(+) T cells were detected in 16/30 patients, with or without EP. At week 24, before cross-over, both delivery methods led to increased CD4(+) and CD8(+) vaccine-specific T cells with a trend to a greater effect with EP. PSA doubling time increased significantly from 11.97 months pre-treatment to 16.82 months over the 72-week follow-up (p = 0.0417), with no clear differential effect of EP. The high frequency of immunological responses to DOM-PSMA(27) vaccination and the clinical effects are sufficiently promising to warrant further, randomized testing.

  5. 基于小波低频系数基因芯片数据的特征提取%Wavelet low-frequency Coefficients for Feature Extraction of Gene Microarray data

    Institute of Scientific and Technical Information of China (English)

    刘玉杰; 刘毅慧

    2011-01-01

    Feature extraction and classification are the key issues in the pattern recognition field. In the paper, we use the wavelet analysis theory and the support vector machine theory to build a classifier which can distinguish cancer tissue from prostate cancer gene microarray data. We extract wavelet low - frequency coefficients to characterize the features of prostate cancer gene microarray data, then feed the coefficients to the classifier. In these experiments, we extract dbl wavelet low -frequency coefficients at level 4 and the correct classification rate is 93. 53% . The correct classification rate of the haar wave is 92.94%. There is little difference using different wavelets.%特征提取和分类是模式识别中的关键问题.结合小波分析理论和支持向量机理论,构造分类器模型,将前列腺癌基因芯片数据分成癌症和正常两种.提取小波低频系数表征原始数据并送入支持向量机分类器分类,实验证明:提取db1小波4层分解下的低频系数,送入分类器分类后正确分类率达到93.53%.Haar小波的正确率是92.94%.可见提取不同小波低频系数,得到的分类效果相差不大.

  6. Hereditary fructose intolerance: frequency and spectrum mutations of the aldolase B gene in a large patients cohort from France--identification of eight new mutations.

    Science.gov (United States)

    Davit-Spraul, Anne; Costa, Catherine; Zater, Mokhtar; Habes, Dalila; Berthelot, Jacques; Broué, Pierre; Feillet, François; Bernard, Olivier; Labrune, Philippe; Baussan, Christiane

    2008-08-01

    We investigated the molecular basis of hereditary fructose intolerance (HFI) in 160 patients from 92 families by means of a PCR-based mutation screening strategy, consisting of restriction enzyme digestion and direct sequencing. Sixteen different mutations of the aldolase B (ALDOB) gene were identified in HFI patients. As in previous studies, p.A150P (64%), p.A175D (16%) and p.N335K (5%) were the most common mutated alleles, followed by p.R60X, p.A338V, c.360_363delCAAA (p.N120KfsX30), c.324G>A (p.K108K) and c.625-1G>A. Eight novel mutations were also identified in 10 families with HFI: a one-base deletion (c.146delT (p.V49GfsX27)), a small deletion (c.953del42bp), a small insertion (c.689ins TGCTAA (p.K230MfsX136)), one splice site mutation (c.112+1G>A), one nonsense mutation (c.444G>A (p.W148X)), and three missense mutations (c.170G>C (p.R57P), c.839C>A (p.A280P) and c.932T>C (p.L311P)). Our strategy allows to diagnose 75% of HFI patients using restriction enzymatic analysis and to enlarge the diagnosis to 97% of HFI patients when associated with direct sequencing.

  7. Frequency and origin of haplotypes associated with the beta-globin gene cluster in individuals with trait and sickle cell anemia in the Atlantic and Pacific coastal regions of Colombia.

    Science.gov (United States)

    Fong, Cristian; Lizarralde-Iragorri, María Alejandra; Rojas-Gallardo, Diana; Barreto, Guillermo

    2013-12-01

    Sickle cell anemia is a genetic disease with high prevalence in people of African descent. There are five typical haplotypes associated with this disease and the haplotypes associated with the beta-globin gene cluster have been used to establish the origin of African-descendant people in America. In this work, we determined the frequency and the origin of haplotypes associated with hemoglobin S in a sample of individuals with sickle cell anemia (HbSS) and sickle cell hemoglobin trait (HbAS) in coastal regions of Colombia. Blood samples from 71 HbAS and 79 HbSS individuals were obtained. Haplotypes were determined based on the presence of variable restriction sites within the β-globin gene cluster. On the Pacific coast of Colombia the most frequent haplotype was Benin, while on the Atlantic coast Bantu was marginally higher than Benin. Eight atypical haplotypes were observed on both coasts, being more diverse in the Atlantic than in the Pacific region. These results suggest a differential settlement of the coasts, dependent on where slaves were brought from, either from the Gulf of Guinea or from Angola, where the haplotype distributions are similar. Atypical haplotypes probably originated from point mutations that lost or gained a restriction site and/or by recombination events.

  8. Frequency and origin of haplotypes associated with the beta-globin gene cluster in individuals with trait and sickle cell anemia in the Atlantic and Pacific coastal regions of Colombia

    Directory of Open Access Journals (Sweden)

    Cristian Fong

    2013-01-01

    Full Text Available Sickle cell anemia is a genetic disease with high prevalence in people of African descent. There are five typical haplotypes associated with this disease and the haplotypes associated with the beta-globin gene cluster have been used to establish the origin of African-descendant people in America. In this work, we determined the frequency and the origin of haplotypes associated with hemoglobin S in a sample of individuals with sickle cell anemia (HbSS and sickle cell hemoglobin trait (HbAS in coastal regions of Colombia. Blood samples from 71 HbAS and 79 HbSS individuals were obtained. Haplotypes were determined based on the presence of variable restriction sites within the β-globin gene cluster. On the Pacific coast of Colombia the most frequent haplotype was Benin, while on the Atlantic coast Bantu was marginally higher than Benin. Eight atypical haplotypes were observed on both coasts, being more diverse in the Atlantic than in the Pacific region. These results suggest a differential settlement of the coasts, dependent on where slaves were brought from, either from the Gulf of Guinea or from Angola, where the haplotype distributions are similar. Atypical haplotypes probably originated from point mutations that lost or gained a restriction site and/or by recombination events.

  9. Natural Killer Cells from Patients with Recombinase-Activating Gene and Non-Homologous End Joining Gene Defects Comprise a Higher Frequency of CD56bright NKG2A+++ Cells, and Yet Display Increased Degranulation and Higher Perforin Content

    Directory of Open Access Journals (Sweden)

    Kerry Dobbs

    2017-07-01

    Full Text Available Mutations of the recombinase-activating genes 1 and 2 (RAG1 and RAG2 in humans are associated with a broad range of phenotypes. For patients with severe clinical presentation, hematopoietic stem cell transplantation (HSCT represents the only curative treatment; however, high rates of graft failure and incomplete immune reconstitution have been observed, especially after unconditioned haploidentical transplantation. Studies in mice have shown that Rag−/− natural killer (NK cells have a mature phenotype, reduced fitness, and increased cytotoxicity. We aimed to analyze NK cell phenotype and function in patients with mutations in RAG and in non-homologous end joining (NHEJ genes. Here, we provide evidence that NK cells from these patients have an immature phenotype, with significant expansion of CD56bright CD16−/int CD57− cells, yet increased degranulation and high perforin content. Correlation was observed between in vitro recombinase activity of the mutant proteins, NK cell abnormalities, and in vivo clinical phenotype. Addition of serotherapy in the conditioning regimen, with the aim of depleting the autologous NK cell compartment, may be important to facilitate engraftment and immune reconstitution in patients with RAG and NHEJ defects treated by HSCT.

  10. 电激转化GFP基因在小麦合子和早期原胚中的高频表达%High Frequency of GFP Gene Transient Expression in Electroporated Zygotes and Early Proembryos of Wheat

    Institute of Scientific and Technical Information of China (English)

    王丽萍; 赵洁

    2003-01-01

    用电激法将GFP基因成功转入分离的小麦(Triticum aestivum L.)合子及早期原胚中.在电场强度150 V/cm、电容25 μF、线性DNA浓度200 μg/mL、电激缓冲液pH 7.2的条件下,得到GFP基因在早期原胚中的高频瞬间表达(46.7%).与开花后5 d胚胎的最适电场强度相比,合子和早期原胚因较幼嫩而最适电场强度较低.电激后的一些早期原胚可以在KM8p培养基中培养并继续分裂,分裂后的细胞中也能观察到GFP基因的表达.此外,电激后的合子及2细胞、4细胞和8细胞原胚中没有看到基因表达的嵌合现象.%Green fluorescent protein (GFP) gene was successfully transferred into the isolated zygotes and early proembryos of wheat (Triticum aestivum L.) by electroporation. A frequency, as high as 46.7% of GFP gene transient expression in early proembryos, was achieved under 150 V/cm electric field strength, 25 μF capacitor, 200 μg/mL of linear plasmid DNA and an electroporation buffer at pH 7.2. Compared with five-day-old proembryos, the zygotes and early proembryos needed lower optimum strength of electric field. After culturing in KM8p medium, the electroporated early proembryos divided and GFP gene expression was observed in daughter cells and subsequent divisions. There was no mosaicism of gene expression in the zygotes and 2-, 4- and 8-celled proembryos.

  11. 北京汉族和约鲁巴人群ROR2基因单核苷酸多态性的比较研究%Comparison of minor allele frequencies and haplotype frequencies for single nucleotide polymorphisms in ROR2 gene using HapMap data for Chinese Hans in Beijing and Yoruban in Ibadan in Nigeria

    Institute of Scientific and Technical Information of China (English)

    王红; 赵凯平

    2011-01-01

    Objective:To provide basis for single nucleotide polymorphisms (SNPs) determination and analysis for R0R2 genes related etiologic studies in Chinese Hans in Beijing (CHB) and Yoruban in Iba-dan in Nigeria ( YRI) populations. Methods: SNPs in R0R2 gene were analyzed and compared for minor allele frequencies (MAFs) , haplotype frequencies, linkage disequilibrium patterns, and tag SNPs using CHB and YRI data from HapMap by Haploview 4. 2 program. SNPs were screened for eligibility using quality control criteria of genotyping call rate >80% , Hardy-Weinberg equilibrium test P >0.01, gender difference P>0. 05 and MAF >0. 01. Tag SNPs were determined under the criteria for r2≥0. 8 and logarithm of the odds radio ≥3 in pairwise eligible SNPs and compared between the CHB and YRI samples. Common Tag SNPs for CHB and YRI were reported by Haploview program directly or identified a-mong SNPs which were higly related to Haploview program directly reported tag SNPs by SPSS 13. 0. Results: Among the 404 and 403 SNPs genotyped in ROR2 genes in the CHB and YRI samples released by HapMap project, there were five SNPs located at exon 6 or 9 where changes of alleles for rs 1076112 and rs 10820900 caused missense mutation. Among the 394 SNPs genotyped in both the populations, a total number of 101 (25. 6% ) SNPs were monotonic among which 66 (65. 3% ) SNPs were common in both CHB and YRI. The rs 1135150 and rs2230577 which were monotonic in YRI and eligible in CHB located at exon 9. Nine ungenotyped SNPs in CHB were all eligible in YRI, and 6 out of 10 ungenotyped SNPs in YRI were eligible in CHB. The proportion of common SNPs (214) were 81.4% and 73. 3% in eligible CHB (263) and YRI (292) SNPs where 177 (82. 7% ) had the same minor alleles and 30 SNPs also had MAF difference ratios<20% that represented 11.4% and 10.3% of the total number of eligible SNPs in CHB and YRI respectively. Among the 18 and 26 haplotype blocks formed in 214 common eligible SNPs, two independent

  12. Frequency noise in frequency swept fiber laser

    DEFF Research Database (Denmark)

    Pedersen, Anders Tegtmeier; Rottwitt, Karsten

    2013-01-01

    This Letter presents a measurement of the spectral content of frequency shifted pulses generated by a lightwave synthesized frequency sweeper. We found that each pulse is shifted in frequency with very high accuracy. We also discovered that noise originating from light leaking through the acousto...

  13. Frequency noise in frequency swept fiber laser.

    Science.gov (United States)

    Pedersen, Anders Tegtmeier; Rottwitt, Karsten

    2013-04-01

    This Letter presents a measurement of the spectral content of frequency shifted pulses generated by a lightwave synthesized frequency sweeper. We found that each pulse is shifted in frequency with very high accuracy. We also discovered that noise originating from light leaking through the acousto- optical modulators and forward propagating Brillouin scattering appear in the spectrum.

  14. Evaluation of the frequency of polymorphisms in XRCC1 (Arg399Gln) and XPD (Lys751Gln) genes related to the genome stability maintenance in individuals of the resident population from Monte Alegre, PA/Brazil municipality; Avaliacao da frequencia de polimorfismos nos genes XRCC1 (Arg399Gln) e XPD (Lys751Gln) relacionados a manutencao da estabilidade do genoma em individuos da populacao residente no municipio de Monte Alegre, PA

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Isabelle Magliano

    2010-07-01

    The human exposure to ionizing radiation coming from natural sources is an inherent feature of human life on Earth. Ionizing radiation is a known genotoxic agent, which can affect biological molecules, causing DNA damage and genomic instability. The cellular system of DNA repair plays an important role in maintaining genomic stability by repairing DNA damage caused by genotoxic agents. However, genes related to DNA repair may have their role committed when presenting a certain polymorphism. This study intended to analyze the frequency of single nucleotide polymorphisms (SNPs) in genes of DNA repair XRCC1 (Arg39-9Gln) and XPD (Lys751Gln) in a: population of the city of Monte Alegre, that resides in an area of high exposure to natural radioactivity. Samples of saliva were collected from individuals of the population of Monte Alegre, in which 40 samples were of male and 46 female. Through the use of RFLP (length polymorphism restriction fragment) the frequency of homozygous genotypes and / or heterozygous was determined for polymorphic genes. The XRCC1 gene had 65.4% of the presence of the allele 399Gln and XPD gene had 32.9% of the 751Gln allele. These values are similar to those found in previous studies for the XPD gene, whereas XRCC1 showed a frequency much higher than described in the literature. The. influence of these polymorphisms, which are involved in DNA repair and consequent genotoxicity induced by radiation depends on dose and exposure factors such as smoking, statistically a factor in public health surveillance in the region. This study gathered information and molecular epidemiology for risk assessment of cancer in the population of Monte Alegre. (author)

  15. Genes and Gene Therapy

    Science.gov (United States)

    ... correctly, a child can have a genetic disorder. Gene therapy is an experimental technique that uses genes to ... or prevent disease. The most common form of gene therapy involves inserting a normal gene to replace an ...

  16. Multi-frequency excitation

    KAUST Repository

    Younis, Mohammad I.

    2016-03-10

    Embodiments of multi-frequency excitation are described. In various embodiments, a natural frequency of a device may be determined. In turn, a first voltage amplitude and first fixed frequency of a first source of excitation can be selected for the device based on the natural frequency. Additionally, a second voltage amplitude of a second source of excitation can be selected for the device, and the first and second sources of excitation can be applied to the device. After applying the first and second sources of excitation, a frequency of the second source of excitation can be swept. Using the methods of multi- frequency excitation described herein, new operating frequencies, operating frequency ranges, resonance frequencies, resonance frequency ranges, and/or resonance responses can be achieved for devices and systems.

  17. 甘肃人群人类血小板抗原HPA-15多态性调查%Investigation on gene frequency of human platelet antigen-15 system in Gansu

    Institute of Scientific and Technical Information of China (English)

    唐朝晖; 李国英; 刘圆圆; 薛双林; 王明禄; 李元荣

    2013-01-01

    Objective:To study the polymorphism of human platelet antigen HPA-15 system in Gansu population,and evaluate its role in matching platelet transfusion.Methods:The blood samples were collected from 201 healthy unrelated platelet donors in Gansu blood center for HPA-15 system genotyping using PCR-SSP assay.Results:Gene frequencies of HPA-15a and 15b were 0.6194 and 0.3806.In comparison to other 9 ethnic groups,there were 7 ethnic groups showing significant differences in HPA-15 distribution.The incompatibility ratios in random platelet transfusion were 0.1239 and 0.2365 for HPA-15a and-15b antigens,total of 0.3604.Conclusion:The distribution of HPA-15 system in Gansu population were investigated for the first time.The present data indicate that the ratio of HPA-15 antigen incompatibility in random platelet transfusion is up to 36.04%,providing a basis for further study on matched platelet transfusion.%目的:研究甘肃人群人类血小板抗原HPA-15系统多态性,评估其在血小板配型输注中的作用.方法:采用PCR-SSP技术对201名健康无血缘关系的血小板捐献者进行HPA-15系统基因分型.结果:HPA-15a和15b基因频率分别为0.6194和0.3806;同国内其它9个地区人群的HPA-15分布相比较,与7个地区人群有显著性差异.在随机输血中HPA-15a和15b抗原不配合的机会分别为0.1239和0.2365,a、b抗原不配合率合计为0.3604.结论:本调查数据表明,随机输血中供受者HPA-15抗原不配合比例在甘肃人群中高达36.04%,这对研究血小板同种免疫性疾病和开展相合血小板输注具有指导意义.

  18. The investigation of gene frequency of human platelet antigen-3 system in Gansu%甘肃人群人类血小板抗原HPA-3多态性调查

    Institute of Scientific and Technical Information of China (English)

    李国英; 刘圆圆; 薛双林; 王明禄; 李元荣; 张海红; 方丽华; 唐朝晖

    2013-01-01

    目的:研究甘肃人群人类血小板抗原HPA-3系统多态性,评估其在血小板配型输注中的作用.方法:采用PCR-SSP技术对201名健康无血缘关系的血小板捐献者进行HPA-3系统基因分型.结果:HPA-3a和3b基因频率分别为0.6368和0.3632;同国内其它9个地区人群的HPA-3分布相比较,与5个地区人群有显著性差异.在随机输血中HPA-3a和3b抗原不配合的机会分别为0.1145和0.2411,a、b抗原不配合率合计为0.3556.结论:调查数据表明,随机输血中供受者HPA-3抗原不配合比例在甘肃人群中高达35.56%,这对研究血小板同种免疫性疾病和开展相合血小板输注具有指导意义.%Objective:To study the polymorphism of the human platelet antigen (HPA - 3) system in Gansu population, and evaluate its role in matched platelet transfusion. Methods: Two hundred and one blood samples selected from 201 unrelated platelet donors of Gansu blood center were genotyped for HPA - 3 system using PCR - SSP assay. Results; The distribution of the HPA - 3 alleles were genetic polymorphisms. Gene frequency of 3a and 3b were 0.6368 and 0. 3632. In comparison to other 9 ethnic groups, significant differences were observed in the distribution of HPA - 3 in 5 groups. The chances of incompatibility in random platelet transfusion were 0.1145 and 0.2411 for HPA -3a and -3b antigens, total 3a and 3b was 0. 3556. Conclusion; The distribution of HPA - 3 systems in Gansu population were investigated for the first time. The present data indicate that the chance of HPA -3 antigen incompatibility in random platelet transfusion is up to 35. 56%. This study provides a basis for further stud-y on matched transfusion of platelet.

  19. Frequency selectivity at very low centre frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Pedersen, Christian Sejer; Marquardt, Torsten

    2010-01-01

    A significant factor in the decrease of sensitivity to low-frequency sound is the helicotrema shunt effect. In humans, it causes a slope increase of the middle-ear transfer function (METF) from 6 dB/oct to 12 dB/oct below approximately 50 Hz [Marquardt et al., J.Acoust. Soc. Am. 121, 3628......-3638 (2007)]. Recent experiments showed that the exact frequency varies from individual to individual. Besides, the helicotrema region in the METF has been found to highly influence frequency selectivity for centre frequencies (CFs) below 80 Hz (Jurado and Moore in prep). By using individual METF...... in the shape of the METFs, thought to be affected by the helicotrema impedance. Preliminary analysis indicates that individual differences in the METFs might underlay the observed individual differences in frequency selectivity. Main effects predicted by the calculations are a pronounced flattening off...

  20. Hyperfine phononic frequency comb

    CERN Document Server

    Ganesan, Adarsh; Seshia, Ashwin A

    2016-01-01

    Optical frequency combs [1-8] have resulted in significant advances in optical frequency metrology and found wide application to precise physical measurements [1-4, 9] and molecular fingerprinting [8]. A direct analogue of frequency combs in the phononic or acoustic domain has not been reported to date. In this letter, we report the first clear experimental evidence for a phononic frequency comb. In contrast to the Kerr nonlinearity [10] in optical frequency comb formation, the phononic frequency comb is generated through the intrinsic coupling of a driven phonon mode with an auto-parametrically excited sub-harmonic mode [16]. Through systematic experiments at different drive frequencies and amplitudes, we portray the well-connected process of phononic frequency comb formation and define attributes to control the features [17-18] associated with comb formation in such a system. Further, the interplay between these nonlinear resonances and the well-known Duffing phenomenon [12-14] is also observed. The present...

  1. Static electromagnetic frequency changers

    CERN Document Server

    Rozhanskii, L L

    1963-01-01

    Static Electromagnetic Frequency Changers is about the theory, design, construction, and applications of static electromagnetic frequency changers, devices that used for multiplication or division of alternating current frequency. It is originally published in the Russian language. This book is organized into five chapters. The first three chapters introduce the readers to the principles of operation, the construction, and the potential applications of static electromagnetic frequency changers and to the principles of their design. The two concluding chapters use some hitherto unpublished work

  2. Modeling Frequency Comb Sources

    Directory of Open Access Journals (Sweden)

    Li Feng

    2016-06-01

    Full Text Available Frequency comb sources have revolutionized metrology and spectroscopy and found applications in many fields. Stable, low-cost, high-quality frequency comb sources are important to these applications. Modeling of the frequency comb sources will help the understanding of the operation mechanism and optimization of the design of such sources. In this paper,we review the theoretical models used and recent progress of the modeling of frequency comb sources.

  3. Eastern Frequency Response Study

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N.W.; Shao, M.; Pajic, S.; D' Aquila, R.

    2013-05-01

    This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

  4. ALLELE FREQUENCIES IN MULTIGENE FAMILIES

    Directory of Open Access Journals (Sweden)

    S. Padmadisastra

    2010-11-01

    Full Text Available Results on allelle frequencies in three chromosomes, drawn at randomfrom a diploid population, evolving in equilibrium, at a particular generation, arepresented in this paper. The genes on each chromosome are subject to unbiased andreciprocal gene conversion and mutation. Using the coalescent approach we find theprobability distribution of the allelic configurations in the three chromosomes, andthe moments of the allelic numbers that exist in one of the three chromosomes orin a pair of chromosomes. We also consider the identity coefficients of two genesdrawn at random, one from each of two chromosomes, and the probability that allgenes in the three chromosomes are monomorphic. Numerical examples are alsogiven together with simulation results, and they agree well.

  5. Frequency selective infrared sensors

    Science.gov (United States)

    Davids, Paul; Peters, David W

    2013-05-28

    A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

  6. Freqüência de mutação no códon 12 do gene K-ras no carcinoma ductal invasivo de mama Frequency of mutations at codon 12 of the K--ras gene in invasive ductal breast cancer

    Directory of Open Access Journals (Sweden)

    Sônia Maria Rolim Rosa Lima

    1999-04-01

    Full Text Available Objetivo: pesquisar a freqüência de mutação pontual no códon 12 do gene K-ras, em espécimes cirúrgicos de pacientes portadoras de carcinoma ductal invasivo de mama. Material e Métodos: foram utilizados cortes de 50 espécimes cirúrgicos incluídos em blocos de parafina, de pacientes portadoras de carcinoma ductal invasivo de mama, com graus histológicos II e III. Os cortes destinados ao estudo foram desparafinizados e submetidos a extração do DNA, por meio do emprego da proteinase K. Para a amplificação do fragmento a ser analisado, utilizou-se a reação em cadeia da polimerase, seguida por clivagem com o emprego de enzima de restrição de comprimento variável (RFLP. A verificação da presença de mutação nas amostras foi feita com o emprego de eletroforese em gel de agarose, com marcador de peso molecular "Ladder 123" (GIBCO-BRL, e a documentação dos resultados, mediante fotografia, utilizando-se luz ultravioleta transmitida. Resultados: em cinco dos 50 carcinomas ductais invasivos de mama estudados (10% constatou-se a presença de mutação no códon 12 do gene K-ras, sendo todas elas polimórficas para esse caráter. As afetadas pelos tumores, que apresentavam a referida mutação, encontravam-se na pós-menopausa. Em quatro dos cinco casos em que se constatou a mutação, o grau histológico dos tumores era II e no caso restante III.Purpose: the frequency of point mutation at codon 12 of the K¾ras gene was determined in paraffin blocks of surgical specimens from patients who had ductal invasive breast cancer. Material and Methods: Fifty surgical specimens blocked in paraffin from patients with ductal invasive breast cancer, with histological degree II and III, were used. The polymerase chain reaction (PCR was used for amplification of DNA fragments studied. The material cleavage was obtained with restriction fragment length polymorphisms (RFLP. The electrophoresis in agarose gel, with Ladder 123 (GIBCO-BRL marker, was

  7. Radio frequency detection assembly and method for detecting radio frequencies

    Science.gov (United States)

    Cown, Steven H.; Derr, Kurt Warren

    2010-03-16

    A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

  8. Waveform frequency notching

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W.; Andrews, John

    2017-05-09

    The various technologies presented herein relate to incorporating one or more notches into a radar spectrum, whereby the notches relate to one or more frequencies for which no radar transmission is to occur. An instantaneous frequency is monitored and if the frequency is determined to be of a restricted frequency, then a radar signal can be modified. Modification can include replacing the signal with a signal having a different instantaneous amplitude, a different instantaneous phase, etc. The modification can occur in a WFS prior to a DAC, as well as prior to a sin ROM component and/or a cos ROM component. Further, the notch can be dithered to enable formation of a deep notch. The notch can also undergo signal transitioning to enable formation of a deep notch. The restricted frequencies can be stored in a LUT against which an instantaneous frequency can be compared.

  9. Universal Optical Frequency Comb

    CERN Document Server

    Savchenkov, A A; Liang, W; Ilchenko, V S; Seidel, D; Maleki, L

    2010-01-01

    We demonstrate that whispering gallery mode resonators can be utilized to generate optical frequency combs based on four wave mixing process at virtually any frequency that lies in the transparency window of the resonator host material. We show theoretically how the morphology of the resonator can be engineered to produce a family of spectrally equidistant modes with anomalous group velocity dispersion appropriate for the comb generation. We present experimental results for a frequency comb centered at 794 nm to support our theoretical findings.

  10. Probability and Relative Frequency

    Science.gov (United States)

    Drieschner, Michael

    2016-01-01

    The concept of probability seems to have been inexplicable since its invention in the seventeenth century. In its use in science, probability is closely related with relative frequency. So the task seems to be interpreting that relation. In this paper, we start with predicted relative frequency and show that its structure is the same as that of probability. I propose to call that the `prediction interpretation' of probability. The consequences of that definition are discussed. The "ladder"-structure of the probability calculus is analyzed. The expectation of the relative frequency is shown to be equal to the predicted relative frequency. Probability is shown to be the most general empirically testable prediction.

  11. Frequency Response Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    Etingov, Pavel V.; Kosterev, Dmitry; Dai, T.

    2014-12-31

    Frequency response has received a lot of attention in recent years at the national level, which culminated in the development and approval of North American Electricity Reliability Corporation (NERC) BAL-003-1 Frequency Response and Frequency Bias Setting Reliability Standard. This report is prepared to describe the details of the work conducted by Pacific Northwest National Laboratory (PNNL) in collaboration with the Bonneville Power Administration and Western Electricity Coordinating Council (WECC) Joint Synchronized Information Subcommittee (JSIS) to develop a frequency response analysis tool (FRAT). The document provides the details on the methodology and main features of the FRAT. The tool manages the database of under-frequency events and calculates the frequency response baseline. Frequency response calculations are consistent with frequency response measure (FRM) in NERC BAL-003-1 for an interconnection and balancing authority. The FRAT can use both phasor measurement unit (PMU) data, where available, and supervisory control and data acquisition (SCADA) data. The tool is also capable of automatically generating NERC Frequency Response Survey (FRS) forms required by BAL-003-1 Standard.

  12. Frequency Response Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    Etingov, Pavel V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kosterev, Dmitry [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dai, T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-12-01

    Frequency response has received a lot of attention in recent years at the national level, which culminated in the development and approval of North American Electricity Reliability Corporation (NERC) BAL-003-1 Frequency Response and Frequency Bias Setting Reliability Standard. This report is prepared to describe the details of the work conducted by Pacific Northwest National Laboratory (PNNL) in collaboration with the Bonneville Power Administration and Western Electricity Coordinating Council (WECC) Joint Synchronized Information Subcommittee (JSIS) to develop a frequency response analysis tool (FRAT). The document provides the details on the methodology and main features of the FRAT. The tool manages the database of under-frequency events and calculates the frequency response baseline. Frequency response calculations are consistent with frequency response measure (FRM) in NERC BAL-003-1 for an interconnection and balancing authority. The FRAT can use both phasor measurement unit (PMU) data, where available, and supervisory control and data acquisition (SCADA) data. The tool is also capable of automatically generating NERC Frequency Response Survey (FRS) forms required by BAL-003-1 Standard.

  13. Optimization of frequency quantization

    CERN Document Server

    Tibabishev, V N

    2011-01-01

    We obtain the functional defining the price and quality of sample readings of the generalized velocities. It is shown that the optimal sampling frequency, in the sense of minimizing the functional quality and price depends on the sampling of the upper cutoff frequency of the analog signal of the order of the generalized velocities measured by the generalized coordinates, the frequency properties of the analog input filter and a maximum sampling rate for analog-digital converter (ADC). An example of calculating the frequency quantization for two-tier ADC with an input RC filter.

  14. Frecuencia del polimorfismo Gly1057Asp del gen IRS-2 en un grupo de la población cubana, y su relación con la diabetes mellitus 2 y el sobrepeso Frequency of Gly105Asp polymorphism of the IRS-2 gene in a group of the Cuban population: its relation to Type 2 diabetes mellitus and the overweight

    Directory of Open Access Journals (Sweden)

    Aimée Álvarez Álvarez

    2008-12-01

    Full Text Available INTRODUCCIÓN: la diabetes mellitus tipo 2 es una de las epidemias de mayor impacto a nivel mundial. La susceptibilidad genética constituye un importante factor de riesgo en ella, que se adiciona al efecto de los factores ambientales y al modo de vida. OBJETIVO: explorar el papel del polimorfismo Gly1057Asp del gen IRS-2 en la susceptibilidad genética para la diabetes mellitus tipo 2. MÉTODOS: se estudió la frecuencia del polimorfismo Gly1057Asp del IRS-2 en 499 ciudadanos cubanos, con IMC³22 y INTRODUCTION: Type 2 diabetes mellitus is one of the more hard-bitting pandemic at world level. Genetic susceptibility is an important risk factor of it, as well as the effect of environmental factors, and lifestyles. OBJETIVE: to explore role of Gly1057Asp polymorphism of IRS-2 gene in genetic oversensitivity for Type 2 diabetes mellitus. METHODS: frequency of Gly1057Asp polymorphism of IRS-2 gene in was studied in 499 Cuban citizens, with IMC³22 and <30, aged from 40 to 70, of them, 272 (54,5 % were diabetic people and 277 (45,5 % were non-diabetic. For comparison of frequency of this polymorphism in both groups, we used ²Chi test (p<0,05, and to quantify associations, we used crossed-products ratio. RESULTS: frequency of Asp1057 allele of Gly1057Asp polymorphism of IRS-2 gene was of 49,8 % in diabetic patient group, and of 58,8 % in the group on non-diabetic one (p<0,05, suggesting that this allele confers protection against diabetes. However, this pattern of frequency distribution changes in persons overweighed, in which presence of Asp1057 allele becomes associated with hyperinsulinism. In subjects with family backgrounds of Type 2 diabetes mellitus, protection of Asp1057 allele is not expressed. CONCLUSION: in group of study Cuban population, Asp1057 allele of IRS-2 gene confers protection against Type 2 diabetes mellitus. Overweight and family backgrounds modify this protective action

  15. Carrier frequency of a nonsense mutation in the adenosine deaminase (ADA) gene implies a high incidence of ADA-deficient severe combined immunodeficiency (SCID) in Somalia and a single, common haplotype indicates common ancestry.

    Science.gov (United States)

    Sanchez, Juan J; Monaghan, Gemma; Børsting, Claus; Norbury, Gail; Morling, Niels; Gaspar, H Bobby

    2007-05-01

    Inherited adenosine deaminase (ADA) deficiency is a rare metabolic disorder that causes immunodeficiency, varying from severe combined immunodeficiency (SCID) in the majority of cases to a less severe form in a small minority of patients. Five patients of Somali origin from four unrelated families, with severe ADA-SCID, were registered in the Greater London area. Patients and their parents were investigated for the nonsense mutation Q3X (ADA c7C>T), two missense mutations K80R (ADA c239A>G) and R142Q (ADA c425G>A), and a TAAA repeat located at the 3' end of an Alu element (AluVpA) positioned 1.1 kb upstream of the ADA transcription start site. All patients were homozygous for the haplotype ADA-7T/ADA-239G/ADA-425G/AluVpA7. Among 207 Somali immigrants to Denmark, the frequency of ADA c7C>T and the maximum likelihood estimate of the frequency of the haplotype ADA-7T/ADA-239G/ADA-425G/AluVpA7 were both 0.012 (carrier frequency 2.4%). Based on the analysis of AluVpA alleles, the ADA c7C/T mutation was estimated to be approximately 7,100 years old. Approximately 1 out of 5 - 10000 Somali children will be born with ADA deficiency due to an ADA c7C/T mutation, although within certain clans the frequency may be significantly higher. ADA-SCID may be a frequent immunodeficiency disorder in Somalia, but will be underdiagnosed due to the prevailing socioeconomic and nutritional deprivation.

  16. FET frequency discriminator

    Science.gov (United States)

    Mawhinney, F. D.

    1982-03-01

    The FET Frequency Discriminator is an experimental microwave frequency discriminator developed for use in a specialized set-on VCO frequency memory system. Additional development and evaluation work has been done during this program to more fully determine the applicability of the FET frequency discriminator as a low-cost, expendable receiver front-end for both surveillance and ECM systems. Various methods for adjusting the frequency-to-voltage characteristic of the discriminator as well as the effects of detector characteristics and ambient temperature changes were evaluated. A number of discriminators for use in the 7- to 11-GHz and the 11to 18-GHz bands were fabricated and tested. Interim breadboard and final packaged models were either delivered or installed in developmental frequency systems. The major limitations and deficiencies of the FET frequency discriminator that were reviewed during the program include the effects of temperature, input power level variations, nonlinearity, and component repeatability. Additional effort will be required to advance the developmental status of the FET frequency discriminator to the level necessary for inclusion in low-cost receiver systems, but the basic simplicity of the approach continues to show much promise.

  17. Microfabricated ion frequency standard

    Science.gov (United States)

    Schwindt, Peter; Biedermann, Grant; Blain, Matthew G.; Stick, Daniel L.; Serkland, Darwin K.; Olsson, III, Roy H.

    2010-12-28

    A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.

  18. Breakfast frequency among adolescents

    DEFF Research Database (Denmark)

    Pedersen, Trine Pagh; Holstein, Bjørn E; Damsgaard, Mogens Trab

    2016-01-01

    , quality of family communication and family support. Further, analyses suggested that the associations were more pronounced among girls, immigrants and adolescents from other family structure than traditional. The study highlights the importance of the family setting in promoting regular breakfast......OBJECTIVE: To investigate (i) associations between adolescents' frequency of breakfast and family functioning (close relations to parents, quality of family communication and family support) and (ii) if any observed associations between breakfast frequency and family functioning vary...... (n 3054) from a random sample of forty-one schools. RESULTS: Nearly one-quarter of the adolescents had low breakfast frequency. Low breakfast frequency was associated with low family functioning measured by three dimensions. The OR (95 % CI) of low breakfast frequency was 1·81 (1·40, 2...

  19. Frequency comb swept lasers.

    Science.gov (United States)

    Tsai, Tsung-Han; Zhou, Chao; Adler, Desmond C; Fujimoto, James G

    2009-11-09

    We demonstrate a frequency comb (FC) swept laser and a frequency comb Fourier domain mode locked (FC-FDML) laser for applications in optical coherence tomography (OCT). The fiber-based FC swept lasers operate at a sweep rate of 1kHz and 120kHz, respectively over a 135nm tuning range centered at 1310nm with average output powers of 50mW. A 25GHz free spectral range frequency comb filter in the swept lasers causes the lasers to generate a series of well defined frequency steps. The narrow bandwidth (0.015nm) of the frequency comb filter enables a approximately -1.2dB sensitivity roll off over approximately 3mm range, compared to conventional swept source and FDML lasers which have -10dB and -5dB roll offs, respectively. Measurements at very long ranges are possible with minimal sensitivity loss, however reflections from outside the principal measurement range of 0-3mm appear aliased back into the principal range. In addition, the frequency comb output from the lasers are equally spaced in frequency (linear in k-space). The filtered laser output can be used to self-clock the OCT interference signal sampling, enabling direct fast Fourier transformation of the fringe signals, without the need for fringe recalibration procedures. The design and operation principles of FC swept lasers are discussed and designs for short cavity lasers for OCT and interferometric measurement applications are proposed.

  20. Broadband frequency conversion

    DEFF Research Database (Denmark)

    Sanders, Nicolai Højer; Jensen, Ole Bjarlin; Dam, Jeppe Seidelin;

    that ensures phase matching over a broad spectral range in the BBO crystal. Since the tuning mechanism relies on all-passive components with extremely short response times the proposed method is well suited for short pulse, broad bandwidth laser sources like mode-locked lasers or super-continuum sources......We demonstrate a method for frequency conversion of broadly tunable or broad bandwidth light in a static, passive setup. Using simple optical components like lenses, mirrors and gratings and a BiBO crystal as the nonlinear material, we are able to frequency double a single-frequency, tunable...

  1. Quantum frequency downconversion experiment

    CERN Document Server

    Takesue, Hiroki

    2010-01-01

    We report the first quantum frequency downconversion experiment. Using the difference frequency generation process in a periodically poled lithium niobate waveguide, we successfully observed the phase-preserved frequency downconversion of a coherent pulse train with an average photon number per pulse of $<$1, from the 0.7-$\\mu$m visible wavelength band to the 1.3-$\\mu$m telecom band. We expect this technology to become an important tool for flexible photonic quantum networking, including the realization of quantum repeater systems over optical fiber using atom-photon entanglement sources for the visible wavelength bands.

  2. Pragmatic circuits frequency domain

    CERN Document Server

    Eccles, William

    2006-01-01

    Pragmatic Circuits: Frequency Domain goes through the Laplace transform to get from the time domain to topics that include the s-plane, Bode diagrams, and the sinusoidal steady state. This second of three volumes ends with a-c power, which, although it is just a special case of the sinusoidal steady state, is an important topic with unique techniques and terminology. Pragmatic Circuits: Frequency Domain is focused on the frequency domain. In other words, time will no longer be the independent variable in our analysis. The two other volumes in the Pragmatic Circuits series include titles on DC

  3. Analysis of the CCR5 gene coding region diversity in five South American populations reveals two new non-synonymous alleles in Amerindians and high CCR5*D32 frequency in Euro-Brazilians

    Directory of Open Access Journals (Sweden)

    Angelica B.W. Boldt

    2009-01-01

    Full Text Available The CC chemokine receptor 5 (CCR5 molecule is an important co-receptor for HIV. The effect of the CCR5*D32 allele in susceptibility to HIV infection and AIDS disease is well known. Other alleles than CCR5*D32 have not been analysed before, neither in Amerindians nor in the majority of the populations all over the world. We investigated the distribution of the CCR5 coding region alleles in South Brazil and noticed a high CCR5*D32 frequency in the Euro-Brazilian population of the Paraná State (9.3%, which is the highest thus far reported for Latin America. The D32 frequency is even higher among the Euro-Brazilian Mennonites (14.2%. This allele is uncommon in Afro-Brazilians (2.0%, rare in the Guarani Amerindians (0.4% and absent in the Kaingang Amerindians and the Oriental-Brazilians. R223Q is common in the Oriental-Brazilians (7.7% and R60S in the Afro-Brazilians (5.0%. A29S and L55Q present an impaired response to b-chemokines and occurred in Afro- and Euro-Brazilians with cumulative frequencies of 4.4% and 2.7%, respectively. Two new non-synonymous alleles were found in Amerindians: C323F (g.3729G > T in Guarani (1.4% and Y68C (g.2964A > G in Kaingang (10.3%. The functional characteristics of these alleles should be defined and considered in epidemiological investigations about HIV-1 infection and AIDS incidence in Amerindian populations.

  4. Single frequency semiconductor lasers

    CERN Document Server

    Fang, Zujie; Chen, Gaoting; Qu, Ronghui

    2017-01-01

    This book systematically introduces the single frequency semiconductor laser, which is widely used in many vital advanced technologies, such as the laser cooling of atoms and atomic clock, high-precision measurements and spectroscopy, coherent optical communications, and advanced optical sensors. It presents both the fundamentals and characteristics of semiconductor lasers, including basic F-P structure and monolithic integrated structures; interprets laser noises and their measurements; and explains mechanisms and technologies relating to the main aspects of single frequency lasers, including external cavity lasers, frequency stabilization technologies, frequency sweeping, optical phase locked loops, and so on. It paints a clear, physical picture of related technologies and reviews new developments in the field as well. It will be a useful reference to graduate students, researchers, and engineers in the field.

  5. Microwave Radiometer - high frequency

    Data.gov (United States)

    Oak Ridge National Laboratory — The Microwave Radiometer-High Frequency (MWRHF) provides time-series measurements of brightness temperatures from two channels centered at 90 and 150 GHz. These two...

  6. FINDbase: A worldwide database for genetic variation allele frequencies updated

    NARCIS (Netherlands)

    M. Georgitsi (Marianthi); E. Viennas (Emmanouil); D.I. Antoniou (Dimitris I.); V. Gkantouna (Vassiliki); S. van Baal (Sjozef); E.F. Petricoin (Emanuel F.); K. Poulas (Konstantinos); G. Tzimas (Giannis); G.P. Patrinos (George)

    2011-01-01

    textabstractFrequency of INherited Disorders database (FIND base; http://www.findbase. org) records frequencies of causative genetic variations worldwide. Database records include the population and ethnic group or geographical region, the disorder name and the related gene, accompanied by links to

  7. Effects of low-frequency electromagnetic fields on skin wound healing after the transplantation of gene modified epidermal stem cells%低频电磁场在基因修饰表皮干细胞移植修复创面中的作用**★

    Institute of Scientific and Technical Information of China (English)

    梁玲; 张鸣生; 李新平; 白文芳; 白利明; 朱洪翔; 许伟成; 冯玉; 王鑫; 陈艺

    2013-01-01

    and keratinocyte growth factor for ful-thickness wound repair is a promising approach. Low-frequency electromagnetic fields which are a non-invasive physical stimulation therapy have been recognized as a good method to enhance wound healing. OBJECTIVE:To develop a new strategy to accelerate wound healing by transplanting transfected epidermal stem cel s and keratinocyte growth factor and treating with low-frequency electromagnetic fields in a mouse model. METHODS:Epidermal stem cel s from Sprague-Dawley neonatal rats were isolated and cultured in vitro, then the cel s were labeled with 5-bromo-2-deoxyuridine and transfected by Ad-KGF, a recombinant adenovirus carrying the keratinocyte growth factor. Mice were given to create ful thickness skin wound on the dorsum and randomly assigned to four groups:control group, transplantation of epidermal stem cel s group, transplantation of keratinocyte growth factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group. RESULTS AND CONCLUSION:The best healing pattern was observed in the keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group (P<0.05) at days 9 and 16. 5-Bromo-2-deoxyuridine labeled cel s existed in the wound in the treated groups at day 9. A significantly increased expression of endogenous keratinocyte growth factor was detected in the transplantation of Keratinocyte Growth Factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at day 16. A wel-advanced epithelialization was observed in transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at days 16 and 30. These results suggest that low-frequency

  8. Term frequency inverse document frequency (TF-IDF) technique and ...

    African Journals Online (AJOL)

    Term frequency inverse document frequency (TF-IDF) technique and artificial neural ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL ... Electronic mail contents are extracted and Term Frequency Inverse ...

  9. Frequency Standards and Metrology

    Science.gov (United States)

    Maleki, Lute

    2009-04-01

    Preface / Lute Maleki -- Symposium history / Jacques Vanier -- Symposium photos -- pt. I. Fundamental physics. Variation of fundamental constants from the big bang to atomic clocks: theory and observations (Invited) / V. V. Flambaum and J. C. Berengut. Alpha-dot or not: comparison of two single atom optical clocks (Invited) / T. Rosenband ... [et al.]. Variation of the fine-structure constant and laser cooling of atomic dysprosium (Invited) / N. A. Leefer ... [et al.]. Measurement of short range forces using cold atoms (Invited) / F. Pereira Dos Santos ... [et al.]. Atom interferometry experiments in fundamental physics (Invited) / S. W. Chiow ... [et al.]. Space science applications of frequency standards and metrology (Invited) / M. Tinto -- pt. II. Frequency & metrology. Quantum metrology with lattice-confined ultracold Sr atoms (Invited) / A. D. Ludlow ... [et al.]. LNE-SYRTE clock ensemble: new [symbol]Rb hyperfine frequency measurement - spectroscopy of [symbol]Hg optical clock transition (Invited) / M. Petersen ... [et al.]. Precise measurements of S-wave scattering phase shifts with a juggling atomic clock (Invited) / S. Gensemer ... [et al.]. Absolute frequency measurement of the [symbol] clock transition (Invited) / M. Chwalla ... [et al.]. The semiclassical stochastic-field/atom interaction problem (Invited) / J. Camparo. Phase and frequency noise metrology (Invited) / E. Rubiola ... [et al.]. Optical spectroscopy of atomic hydrogen for an improved determination of the Rydberg constant / J. L. Flowers ... [et al.] -- pt. III. Clock applications in space. Recent progress on the ACES mission (Invited) / L. Cacciapuoti and C. Salomon. The SAGAS mission (Invited) / P. Wolf. Small mercury microwave ion clock for navigation and radioScience (Invited) / J. D. Prestage ... [et al.]. Astro-comb: revolutionizing precision spectroscopy in astrophysics (Invited) / C. E. Kramer ... [et al.]. High frequency very long baseline interferometry: frequency standards and

  10. Studying Genes

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Studying Genes Studying Genes Tagline (Optional) Middle/Main Content Area Other Fact Sheets What are genes? Genes are segments of DNA that contain instructions ...

  11. Single frequency intracavity SRO

    DEFF Research Database (Denmark)

    Abitan, Haim; Buchhave, Preben

    2000-01-01

    Summary form only given. A single resonance optical parametric oscillator (SRO) is inserted intracavity to a CW high power, single frequency, and ring Nd:YVO4 laser. We obtain a stable single frequency CW SRO with output at 1.7-1.9 μm (idler) and a resonating signal at 2.3-2.6 μm. The behavior...... of the two coupled resonators is simulated and the output power from the SRO is described as a function of the diode pumping power supplied to the Nd:YVO4 laser....

  12. Mid-frequency readers

    OpenAIRE

    Nation, Ian Stephen Paul; Anthony, Laurence

    2013-01-01

    This article describes a new free extensive reading resource for learning the mid-frequency words of English and for reading well known texts with minor vocabulary adaptation. A gap exists between the end of graded readers at around 3,000 word families and the vocabulary size needed to read unsimplified texts at around 8,000 word families. Mid-frequency readers are designed to fill this gap. They consist of texts from Project Gutenberg adapted for learners with a vocabulary size of 4,000 word...

  13. Molecular analysis of a 444 bp fragment of the bovine leukaemia virus gp51 env gene reveals a high frequency of non-silent point mutations and suggests the presence of two subgroups of BLV in Chile.

    Science.gov (United States)

    Felmer, R; Muñoz, G; Zúñiga, J; Recabal, M

    2005-06-15

    With the aim of achieve a better understanding of the epidemiology and distribution of bovine leukaemia virus (BLV) infection in Chile, we assessed the suitability of using DNA isolated from the leukocyte fraction of bulk milk samples to carry out PCR-RFLP and DNA sequence analysis. The env fragment of BLV was successfully amplified from 33 serologically positive bulk milk samples collected from different geographical areas in the south of Chile. Restriction analysis allowed to classify 17 isolates within the Australian subgroup and 16 within the Belgium subgroup. DNA sequence and multiple alignment analysis of eight Chilean isolates showed a significantly higher frequency of single and double nucleotide substitutions. Most of these mutations were non-silent, resulting in changes at the protein level in several important epitopes of gp51. The Chilean sequences and 59 BLV env sequences available at GenBank, were subjected to a phylogenetic analysis, resulting in four different clusters. The groups identified were not related to those previously defined by restriction analysis. Chilean isolates were included in two different clusters and were genetically not related to isolates collected from neighbouring countries. Considering our results we can conclude: (i) bulk milk samples are suitable to identify the presence of BLV allowing epidemiological and genetic studies to be conducted on large geographical areas; (ii) at least four different genetic groups of BLV were identified by phylogenetic analysis, with Chilean isolates included in two different sub clusters.

  14. Multiband frequency selective surface

    Science.gov (United States)

    Wu, Te-Kao

    1998-10-01

    This paper addresses the similarity of microwave/millimeter wave frequency selective surfaces (FSS) to optical filters. Specifically, the design approaches of the 4-band FSSs developed for NASA's CASSINI high gain antenna are described in detail. Representative RF test results are given to demonstrate the validity of these designs. These design approaches are very general and can be applied to multiband optical filters.

  15. High frequency electromagnetic dosimetry

    CERN Document Server

    Sánchez-Hernández, David A

    2009-01-01

    Along with the growth of RF and microwave technology applications, there is a mounting concern about the possible adverse effects over human health from electromagnetic radiation. Addressing this issue and putting it into perspective, this groundbreaking resource provides critical details on the latest advances in high frequency electromagnetic dosimetry.

  16. Frequency scanning microstrip antennas

    DEFF Research Database (Denmark)

    Danielsen, Magnus; Jørgensen, Rolf

    1979-01-01

    The principles of using radiating microstrip resonators as elements in a frequency scanning antenna array are described. The resonators are cascade-coupled. This gives a scan of the main lobe due to the phase-shift in the resonator in addition to that created by the transmission line phase...

  17. Frequency of orthodontic extraction

    Directory of Open Access Journals (Sweden)

    Camila de S. Dardengo

    2016-02-01

    Full Text Available Introduction: The option of dental extraction for orthodontic purposes has been debated for more than 100 years, including periods when it was widely used in treatment, including the present, during which other methods are used to avoid dental extractions. The objective was to analyze the frequency of tooth extraction treatment performed between 1980 and 2011 at the Orthodontic Clinic of Universidade Estadual do Rio de Janeiro (UERJ. Material and Methods: The clinical records of 1484 patients undergoing orthodontic treatment were evaluated. The frequency of extractions was evaluated with regard to sex, Angle's classification, the different combinations of extractions and the period when orthodontic treatment began. Chi-square test was used to determine correlations between variables, while the chi-square test for trends was used to assess the frequency of extractions over the years. Results: There was a reduction of approximately 20% in the frequency of cases treated with tooth extraction over the last 32 years. The most frequently extracted teeth were first premolars. Patients with Class I malocclusion showed fewer extractions, while Class II patients underwent a higher number of extraction treatment. There were no statistically significant differences with regard to sex. Conclusion: New features introduced into the orthodontic clinic and new esthetic concepts contributed to reducing the number of cases treated with dental extractions. However, dental extractions for orthodontic purposes are still well indicated in certain cases.

  18. All-frequency reflectionlessness

    CERN Document Server

    Philbin, T G

    2016-01-01

    We derive planar permittivity profiles that do not reflect perpendicularly exiting radiation of any frequency. The materials obey the Kramers-Kronig relations and have no regions of gain. Reduction of the Casimir force by means of such materials is also discussed.

  19. Multiple Frequency Parametric Sonar

    Science.gov (United States)

    2015-09-28

    300003 1 MULTIPLE FREQUENCY PARAMETRIC SONAR STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and...beams. However, the multiple nonlinear interactions are not taken advantage of in order to generate additional efficiencies, bandwidth, and SNR...array. [0050] It will be understood that many additional changes in details, materials , steps, and arrangements of parts which have been described

  20. HIGHER FREQUENCY ULTRASONIC LIGHT MODULATORS.

    Science.gov (United States)

    LIGHT), (* MODULATORS , (*ULTRASONIC RADIATION, MODULATORS ), OPTICAL COMMUNICATIONS, BANDWIDTH, TRANSDUCERS, HIGH FREQUENCY, VERY HIGH FREQUENCY, ATTENUATION, DATA PROCESSING, OPTICAL EQUIPMENT, ANALOG COMPUTERS, THEORY.

  1. A novel donor splice site in intron 11 of the CFTR gene, created by mutation 1811 + 1.6kbA {yields} G, produces a new exon: High frequency in spanish cystic fibrosis chromosomes and association with severe phenotype

    Energy Technology Data Exchange (ETDEWEB)

    Chillon, M.; Casals, T.; Gimenez, J.; Ramos, D.; Nunes, V.; Estivill, X. [Cancer Research Institute, Barcelona (Spain); Doerk, T.; Will, K. [Medizinische Hochschule Hannover (Germany); Fonknechten, N. [Institut Cochin de Genetique Moleculaire, Paris (France)

    1995-03-01

    mRNA analysis of the cystic fibrosis transmembrane regulator (CFTR) gene in tissues of cystic fibrosis (CF) patients has allowed us to detect a cryptic exon. The new exon involves 49 base pairs between exons 11 and 12 and is due to a point mutation (1811+1.6bA{yields}G) that creates a new donor splice site in intron 11. Semiquantitative mRNA analysis showed that 1811+1.6kbA{r_arrow}G-mRNA was 5-10-fold less abundant than {triangle}F508 mRNA. Mutations 1811+1.6kbA{yields}G was found in 21 Spanish and 1 German CF chromosome(s), making it the fourth-most-frequent mutation (2%) in the Spanish population. Individuals with genotype {triangle}F508/1811+1.6kbA{yields}G have only 1%-3% of normal CFTR mRNA. This loss of 97% of normal CFTR mRNA must be responsible for the pancreatic insufficiency and for the severe CF phenotype in these patients. 30 refs., 3 figs., 2 tabs.

  2. Microwave Frequency Multiplier

    Science.gov (United States)

    Velazco, J. E.

    2017-02-01

    High-power microwave radiation is used in the Deep Space Network (DSN) and Goldstone Solar System Radar (GSSR) for uplink communications with spacecraft and for monitoring asteroids and space debris, respectively. Intense X-band (7.1 to 8.6 GHz) microwave signals are produced for these applications via klystron and traveling-wave microwave vacuum tubes. In order to achieve higher data rate communications with spacecraft, the DSN is planning to gradually furnish several of its deep space stations with uplink systems that employ Ka-band (34-GHz) radiation. Also, the next generation of planetary radar, such as Ka-Band Objects Observation and Monitoring (KaBOOM), is considering frequencies in the Ka-band range (34 to 36 GHz) in order to achieve higher target resolution. Current commercial Ka-band sources are limited to power levels that range from hundreds of watts up to a kilowatt and, at the high-power end, tend to suffer from poor reliability. In either case, there is a clear need for stable Ka-band sources that can produce kilowatts of power with high reliability. In this article, we present a new concept for high-power, high-frequency generation (including Ka-band) that we refer to as the microwave frequency multiplier (MFM). The MFM is a two-cavity vacuum tube concept where low-frequency (2 to 8 GHz) power is fed into the input cavity to modulate and accelerate an electron beam. In the second cavity, the modulated electron beam excites and amplifies high-power microwaves at a frequency that is a multiple integer of the input cavity's frequency. Frequency multiplication factors in the 4 to 10 range are being considered for the current application, although higher multiplication factors are feasible. This novel beam-wave interaction allows the MFM to produce high-power, high-frequency radiation with high efficiency. A key feature of the MFM is that it uses significantly larger cavities than its klystron counterparts, thus greatly reducing power density and arcing

  3. [Frequency dependance of compliance].

    Science.gov (United States)

    Gayrard, P

    1975-01-01

    Resistance of peripheral or "small" airways is only a small part of the total pulmonary resistance (Raw). Even considerable obstruction in these airways will have little effect on total resistance. Conversely this will lead to inequality in the time constants of units in parallel, and dynamic lung compliance (C dyn) shall fall as respiratory frequence increases. C dyn is measured from simultaneous recordings of transpulmonary pressure (esophageal balloon) and volume obtained from a volume displacement plethysmograph. If Raw and static compliance are found to be normal, the frequency dependance of compliance will result from peripheral airway obstruction only. Early stages of chronic airway obstruction can be established by this method. However this appear not suitable for wide-scale studies.

  4. Radio frequency ion source

    CERN Document Server

    Shen Guan Ren; Gao Fu; LiuNaiYi

    2001-01-01

    The study on Radio Frequency Ion Source is mainly introduced, which is used for CIAE 600kV ns Pulse Neutron Generator; and obtained result is also presented. The RF ion source consists of a diameter phi 25 mm, length 200 mm, coefficient of expansion =3.5 mA, beam current on target >=1.5 mA, beam spot =100 h.

  5. Frequency steerable acoustic transducers

    Science.gov (United States)

    Senesi, Matteo

    Structural health monitoring (SHM) is an active research area devoted to the assessment of the structural integrity of critical components of aerospace, civil and mechanical systems. Guided wave methods have been proposed for SHM of plate-like structures using permanently attached piezoelectric transducers, which generate and sense waves to evaluate the presence of damage. Effective interrogation of structural health is often facilitated by sensors and actuators with the ability to perform electronic, i.e. phased array, scanning. The objective of this research is to design an innovative directional piezoelectric transducer to be employed for the localization of broadband acoustic events, or for the generation of Lamb waves for active interrogation of structural health. The proposed Frequency Steerable Acoustic Transducers (FSATs) are characterized by a spatial arrangement of active material which leads to directional characteristics varying with frequency. Thus FSATs can be employed both for directional sensing and generation of guided waves without relying on phasing and control of a large number of channels. The analytical expression of the shape of the FSATs is obtained through a theoretical formulation for continuously distributed active material as part of a shaped piezoelectric device. The FSAT configurations analyzed in this work are a quadrilateral array and a geometry which corresponds to a spiral in the wavenumber domain. The quadrilateral array is experimentally validated, confirming the concept of frequency-dependent directionality. Its limited directivity is improved by the Wavenumber Spiral FSAT (WS-FSAT), which, instead, is characterized by a continuous frequency dependent directionality. Preliminary validations of the WS-FSAT, using a laser doppler vibrometer, are followed by the implementation of the WS-FSAT as a properly shaped piezo transducer. The prototype is first used for localization of acoustic broadband sources. Signal processing

  6. Immunoglobulin genes

    Energy Technology Data Exchange (ETDEWEB)

    Honjo, T. (Kyoto Univ. (Japan)); Alt, F.W. (Columbia Univ., Dobbs Ferry, NY (USA). Hudson Labs.); Rabbitts, T.H. (Medical Research Council, Cambridge (UK))

    1989-01-01

    This book reports on the structure, function, and expression of the genes encoding antibodies in normal and neoplastic cells. Topics covered are: B Cells; Organization and rearrangement of immunoglobin genes; Immunoglobin genes in disease; Immunoglobin gene expression; and Immunoglobin-related genes.

  7. Orthogonal Frequency Division Multiplexing System with Frequency Offset Estimation

    Directory of Open Access Journals (Sweden)

    Meghashree D.Nimje

    2013-03-01

    Full Text Available Orthogonal Frequency Division Multiplexing (OFDM system, use a large number of parallel narrowband subcarriers instead of a single wide-band carrier to transport information. Orthogonal frequency division multiplexing is the modulation technique use in digital communication systems . Carrier frequency offset occurs due to Doppler effect or noise. Carrier frequency offsets (CFOs is the Offset between the transmitter and the receiver oscillators .CFO damages the orthogonality of the carries ,resulting in degradation of the systems performance. Carrier frequency offset estimation method is discussed in this paper. In this paper one complex training sequence use, which can effectively estimate carrier frequency offset in the time domain and frequency domain. Here fine and coarse frequency is estimated to improve the improve the system performance. This paper shows the estimation range for frequency offset can be improve to large extent..

  8. Influence of different frequency impulse electromagnetic fields on osteoprotegerin gene knockout mice with osteoporosis%不同频率脉冲电磁场对骨保护素基因敲除小鼠骨质疏松影响

    Institute of Scientific and Technical Information of China (English)

    刘亚林; 魏丽; 贺晓晔; 张新玉

    2011-01-01

    Objective To study the optimal treatment frequency of pulsed electromagnetic fields for osteoporosis by intervening osteoprotegerin gene knockout osteoporosis mice with different frequency impulse electromagnetic fields.Methods Thirty osteoprotegerin knockout mice aged 8 weeks old were randomly divided into three groups, 10 each.Group A did not receive pulsed electromagnetic fields treatment.Group B received pulsed electromagnetic fields treatment at 8 Hz frequency with 4.0 mT intensity, 20 minutes daily, totally for 30 days.Group C received pulsed electromagnetic fields treatment at 32 Hz frequency with 4.0 mT intensity, 20 minutes daily, totally for 30 days.Each group was measured bone density by dual energy X-ray absorptiometry before and after treatment.Results After treatment, the bone density in group B and C was different from that in group A(P<0.05), and there was no significant difference between group B and group C(P>0.05).Conclusion The pulsed electromagnetic fields treatment is effective for osteoprotegerin gene knockout osteoporosis mice, and the frequencies from 8 Hz to 32 Hz can get the same therapeutic effect.%目的:采用不同频率的脉冲电磁场干预骨保护素基因敲除小鼠骨质疏松模型,探讨脉冲电磁场治疗骨质疏松的适宜频率.方法:8周龄雌雄各半骨保护素基因敲除小鼠30只,随机分为A,B,C组,每组各10只,A组为对照组,不进行干预;B组小鼠每天在强度为4 mT,频率为8 Hz的磁场中照射治疗20 min,共30 d;C组小鼠每天在强度为4mT,频率为32 Hz的磁场中照射治疗20 min,共30 d.各组小鼠在治疗前及治疗30 d后用双能X线检测骨密度值.结果:治疗后B,C组骨密度值与A组比较差异有统计学意义(P0.05).结论:脉冲电磁场对骨保护素基因敲除小鼠骨质疏松有治疗效果,频率为8~32 Hz的磁场治疗疗效相同.

  9. 精神分裂症患者5-羟色胺2A受体基因T102C基因型频率的地区差异%Regional differences of genotype frequency of 5-hydroxytryptamine 2A receptor gene T102C of schizophrenics patients

    Institute of Scientific and Technical Information of China (English)

    汪广剑; 王云征; 仲爱芳; 张理义; 王焕林; 赵汉清; 余海鹰; 瞿发林; 苏宗荣; 胡传荣

    2005-01-01

    背景:由于分子遗传学技术的发展,关于精神疾病与分子遗传的研究日趋增多,但结论不尽一致,对5-羟色胺2A受体基因T102C基因型频率分布是否有地区、种族差异尚需要更多证实.目的:分析精神分裂症患者5-羟色胺2A受体基因T102C基因型频率在地理上的分布设计:以精神分裂症患者为脱察对象的抽样调查.单位:常州和平医院精神科.对象:实验于 1999-01/2003-08在解放军第102医院完成.选取符合中国精神疾病分类和诊断标准第三版关于精神分裂症诊断标准的患者177例,来自不同省区汉族军人,年龄18~45岁,病程1个月~20年.方法:采集117例精神分裂症患者的血样进行聚合酶链反应检测,并比较不同省区区正常对照人群5-羟色胺2A受体基因型频率的分布有何差异.应用常规苯酚氯仿法抽提DNA,目的DNA的聚合酶链反应扩增及电泳检测,5-羟色胺2A受体基因T102C基因片断扩增的引物序列:5'-TCT GCT ACA AGT TCT GGC TT-3'.5'-CTG CAG CTY TTT CTC TAGGG-3';采用50 μL反应体系,DNA 0.5 μg,引物50 pmol,TagDNA酶2U加dNTP至终浓度200μmol/L.主要观察指标:精神分裂症患者DNA电泳检测及5-羟色胺2A受体基因型频率分布.结果:5-羟色胺2A受体各基因型频率分布为:A1A1,0.07~0.33;A1A2,0.50~0.72;A2A2,0.17~0.29.基因型频率在不同地区的相关分析:A1A1,x2=4.44,P=0.617 1,P>0.05;A1A2,x2=1.14,P=0.942 2,P>0.05;A2A2,x2=0.93,P=0.985 7,P>0.05.结论:117例精神分裂症患者5-羟色胺2A受体基因T102C基因型频率的地理分布比较均一.%BACKGROUND:Now researches on psychiatric disease and molecular heredity are becoming more and more gradually because of the development of molecular genetics,but conclusions are controversial,and for the time being there are no reports about whether there are regional differences and ethnical differences in the distribution of genotype frequency of 5-hydroxytryptamine 2A receptor gene T

  10. DEMODULATION OF FREQUENCY OR SPACE MODULATED LIGHT.

    Science.gov (United States)

    LIGHT , DEMODULATION), (*OPTICAL COMMUNICATIONS, FREQUENCY MODULATION), (*FREQUENCY MODULATION, LIGHT ), OPTICAL TRACKING, BEAMS(ELECTROMAGNETIC), DEFLECTION, MICROWAVE FREQUENCY, ELECTRON BEAMS, PHOTOCATHODES

  11. Resonance frequency analysis

    Directory of Open Access Journals (Sweden)

    Rajiv K Gupta

    2011-01-01

    Full Text Available Initial stability at the placement and development of osseointegration are two major issues for implant survival. Implant stability is a mechanical phenomenon which is related to the local bone quality and quantity, type of implant, and placement technique used. The application of a simple, clinically applicable, non-invasive test to assess implant stability and osseointegration is considered highly desirable. Resonance frequency analysis (RFA is one of such techniques which is most frequently used now days. The aim of this paper was to review and analyze critically the current available literature in the field of RFA, and to also discuss based on scientific evidence, the prognostic value of RFA to detect implants at risk of failure. A search was made using the PubMed database to find all the literature published on "Resonance frequency analysis for implant stability" till date. Articles discussed in vivo or in vitro studies comparing RFA with other methods of implant stability measurement and articles discussing its reliability were thoroughly reviewed and discussed. A limited number of clinical reports were found. Various studies have demonstrated the feasibility and predictability of the technique. However, most of these articles are based on retrospective data or uncontrolled cases. Randomized, prospective, parallel-armed longitudinal human trials are based on short-term results and long-term follow up are still scarce in this field. Nonetheless, from available literature, it may be concluded that RFA technique evaluates implant stability as a function of stiffness of the implant bone interface and is influenced by factors such as bone type, exposed implant height above the alveolar crest. Resonance frequency analysis could serve as a non-invasive diagnostic tool for detecting the implant stability of dental implants during the healing stages and in subsequent routine follow up care after treatment. Future studies, preferably randomized

  12. Microwave Frequency Polarizers

    Science.gov (United States)

    Ha, Vien The; Mirel, Paul; Kogut, Alan J.

    2013-01-01

    This article describes the fabrication and analysis of microwave frequency polarizing grids. The grids are designed to measure polarization from the cosmic microwave background. It is effective in the range of 500 to 1500 micron wavelength. It is cryogenic compatible and highly robust to high load impacts. Each grid is fabricated using an array of different assembly processes which vary in the types of tension mechanisms to the shape and size of the grids. We provide a comprehensive study on the analysis of the grids' wire heights, diameters, and spacing.

  13. Frequency Dependent Attenuation Revisited

    CERN Document Server

    Richard, Kowar; Xavier, Bonnefond

    2009-01-01

    The work is inspired by thermo-and photoacoustic imaging, where recent efforts are devoted to take into account attenuation and varying wave speed parameters. In this paper we study causal equations describing propagation of attenuated pressure waves. We review standard models like frequency power laws and and the thermo-viscous equation. The lack of causality of standard models in the parameter range relevant for photoacoustic imaging requires to derive novel equations. The main ingredients for deriving causal equations are the Kramers-Kronig relation and the mathematical concept of linear system theory. The theoretical results of this work are underpined by numerical experiments.

  14. High frequency electromagnetic tomography

    Energy Technology Data Exchange (ETDEWEB)

    Daily, W.; Ramirez, A.; Ueng, T.; Latorre, R.

    1989-09-01

    An experiment was conducted in G Tunnel at the Nevada Test Site to evaluate high frequency electromagnetic tomography as a candidate for in situ monitoring of hydrology in the near field of a heater placed in densely welded tuff. Tomographs of 200 MHz electromagnetic permittivity were made for several planes between boreholes. Data were taken before the heater was turned on, during heating and during cooldown of the rockmass. This data is interpreted to yield maps of changes in water content of the rockmass as a function of time. This interpretation is based on laboratory measurement of electromagnetic permittivity as a function of water content for densely welded tuff. 8 refs., 6 figs.

  15. Lunch frequency among adolescents

    DEFF Research Database (Denmark)

    Pedersen, Trine Pagh; Holstein, Bjørn E; Krølner, Rikke

    2016-01-01

    frequency was most common among students who were boys, 13- and 15-year-olds, from medium and low family social class, descendants of immigrants, living in a single-parent family and in a reconstructed family. School-level analyses suggested that having access to a canteen at school was associated with low...... students appears to be largely influenced by sociodemographic factors. Additionally, the presence of an adult during lunch breaks promotes frequent lunch consumption while availability of a canteen may discourage frequent lunch consumption. These findings vary between older and younger students....

  16. Radio Frequency Identification

    Indian Academy of Sciences (India)

    V Rajaraman

    2017-06-01

    Radio Frequency Identification (RFID) has been around sinceearly 2000. Its use has currently become commonplace as thecost of RFID tags has rapidly decreased. RFID tags have alsobecome more ‘intelligent’ with the incorporation of processorsand sensors in them. They are widely used now in manyinnovative ways. RFIDs are an integral part of Internet ofThings (IOT) and IT systems of smart cities. In this article,we introduce the technology used by RFID systems, illustratetheir use in several applications, and discuss problems of privacyand security when they are used.

  17. Mutation frequency analysis of mitochondrial ND1 gene associated with Leber hereditary optic neuropathy in Chinese population%中国人群Leber遗传性视神经病变线粒体ND1基因突变频谱分析

    Institute of Scientific and Technical Information of China (English)

    赵福新; 周翔天; 张娟娟; 瞿佳; 冀延春; 章豫; 周晖晖; 戴显宁; 管敏鑫

    2012-01-01

    frequency of mitochondrial NDI gene associated with LHON in Chinese population. Methods The proposal of the study was approved by Ethic Committee of Wenzhou Medical College.Written informed consent was obtained from each subject initial of this trial.Eight hundred and ninety-four LHON patients and 134 normal subjects were collected.Genomic DNA was extracted from peripheral blood leukocytes of the all participants.Polymerase chain reaction (PCR) was used to amplify and sequence analysis of the mitochondrial ND1 gene was performed and aligned with revised Cambridge Reference Sequence(rCRS) of mitochondrial DNA.Then mutated gene frequency was screened and analyzed. Results Mutational analysis of mitochondrial ND1 gene in 894 LHON patients revealed the presence of G3316A,T3394C,G3460A,C3497T,G3635A,G3733A,and T4216C.11.19% LHON patients (100/894 ) were found to be associated with the gene mutations mentioned above,and 3.24% patients (29/894) showed the co-occurrence of three primary mutations.Mutation frequencies in LHON patients were 2.57%,2.23%,1.45%,3.80%,0.67%,0.11%,0.34%,respectively,and G3316A,T3394C,C3497T and T4216C also were detected in 134 normal controls with the mutation frequencies of 4.48%,2.99%,4.48% and 1.49%,respectively.Mutation frequency analysis showed an insignificant difference in the mutations of G3316A,T3394C,C3497T and T4216C between LHON patients and normal controls (x2 =0.926,P=0.336;x2 =0.052,P=0.820; x2 =0.142,P=0.707;P=0.129).G3376A,G3496T,G3700A,A4136G,T4160C and C4171A were absent in Chinese LHON patients. Conclusions Mitoehondrial ND1 gene in LHON is a mutational hotspot in Chinese population,11.19% (100/894)associated with LHON was caused by ND1 gene mutation.G3635A,G3733A may be rare pathological mutation in Chinese population.However,G3316A,T3394C,C3497T and T4216C are insufficient to produce the clinical phenotype,but they may play a synergic role for penetrance and phenotypic manifestation in LHON.

  18. The Genetic Landscape of Hematopoietic Stem Cell Frequency in Mice

    Directory of Open Access Journals (Sweden)

    Xiaoying Zhou

    2015-07-01

    Full Text Available Prior efforts to identify regulators of hematopoietic stem cell physiology have relied mainly on candidate gene approaches with genetically modified mice. Here we used a genome-wide association study (GWAS strategy with the hybrid mouse diversity panel to identify the genetic determinants of hematopoietic stem/progenitor cell (HSPC frequency. Among 108 strains, we observed ∼120- to 300-fold variation in three HSPC populations. A GWAS analysis identified several loci that were significantly associated with HSPC frequency, including a locus on chromosome 5 harboring the homeodomain-only protein gene (Hopx. Hopx previously had been implicated in cardiac development but was not known to influence HSPC biology. Analysis of the HSPC pool in Hopx−/− mice demonstrated significantly reduced cell frequencies and impaired engraftment in competitive repopulation assays, thus providing functional validation of this positional candidate gene. These results demonstrate the power of GWAS in mice to identify genetic determinants of the hematopoietic system.

  19. Multiple frequency atmospheric radar techniques

    Science.gov (United States)

    Stitt, Gary Richard

    The use of multiple frequency coding to improve the vertical resolution of pulsed-Doppler very high frequency atmospheric radars, especially with regards to the two-frequency techniques known as frequency domain interferometry (FDI), is presented. This technique consists of transmitting alternate pulses on two distinct carrier frequencies. The two resulting time series are used to evaluate the normalized cross-correlation function, whose magnitude and phase are related to the thickness and position of a scattering layer. These same time series are also used to evaluate cross-spectra, which yield magnitude and phase values for each Doppler frequency component of the return signal.

  20. Frequency Population Growth Rate

    Directory of Open Access Journals (Sweden)

    Nouralah Salehi Asfiji

    2012-10-01

    Full Text Available The Solow growth model assumes that labor force grows exponentially. That is not a realistic assumption. In generalized logistic equations that describes more accurately population growth. Economic growth is not a smooth process. Real GDP has fluctuations in the growth rate. We call these fluctuations business cycles. Business cycle theory came about from the failures of classical economics in being able to illuminate on the causes of the Great Depression. The logistic growth model to explain changes in population growth rates are not. In this paper a new analysis of the population growth rate in the frequency space is described with mathematical logic and economic reasoning, so that, firstly, to a higher level of capital per capita, or at least equal to the Solow growth model reaches Second, the limits of saturation (Carrying-Capacity is not, and ultimately, population growth rates have an impact on long-term per capita amounts. The initial classic assumption is changed in this article based on the available frequencies in the population growth equation.

  1. Malaria haplotype frequency estimation.

    Science.gov (United States)

    Wigger, Leonore; Vogt, Julia E; Roth, Volker

    2013-09-20

    We present a Bayesian approach for estimating the relative frequencies of multi-single nucleotide polymorphism (SNP) haplotypes in populations of the malaria parasite Plasmodium falciparum by using microarray SNP data from human blood samples. Each sample comes from a malaria patient and contains one or several parasite clones that may genetically differ. Samples containing multiple parasite clones with different genetic markers pose a special challenge. The situation is comparable with a polyploid organism. The data from each blood sample indicates whether the parasites in the blood carry a mutant or a wildtype allele at various selected genomic positions. If both mutant and wildtype alleles are detected at a given position in a multiply infected sample, the data indicates the presence of both alleles, but the ratio is unknown. Thus, the data only partially reveals which specific combinations of genetic markers (i.e. haplotypes across the examined SNPs) occur in distinct parasite clones. In addition, SNP data may contain errors at non-negligible rates. We use a multinomial mixture model with partially missing observations to represent this data and a Markov chain Monte Carlo method to estimate the haplotype frequencies in a population. Our approach addresses both challenges, multiple infections and data errors.

  2. High-frequency ECG

    Science.gov (United States)

    Tragardh, Elin; Schlegel, Todd T.

    2006-01-01

    The standard ECG is by convention limited to 0.05-150 Hz, but higher frequencies are also present in the ECG signal. With high-resolution technology, it is possible to record and analyze these higher frequencies. The highest amplitudes of the high-frequency components are found within the QRS complex. In past years, the term "high frequency", "high fidelity", and "wideband electrocardiography" have been used by several investigators to refer to the process of recording ECGs with an extended bandwidth of up to 1000 Hz. Several investigators have tried to analyze HF-QRS with the hope that additional features seen in the QRS complex would provide information enhancing the diagnostic value of the ECG. The development of computerized ECG-recording devices that made it possible to record ECG signals with high resolution in both time and amplitude, as well as better possibilities to store and process the signals digitally, offered new methods for analysis. Different techniques to extract the HF-QRS have been described. Several bandwidths and filter types have been applied for the extraction as well as different signal-averaging techniques for noise reduction. There is no standard method for acquiring and quantifying HF-QRS. The physiological mechanisms underlying HF-QRS are still not fully understood. One theory is that HF-QRS are related to the conduction velocity and the fragmentation of the depolarization wave in the myocardium. In a three-dimensional model of the ventricles with a fractal conduction system it was shown that high numbers of splitting branches are associated with HF-QRS. In this experiment, it was also shown that the changes seen in HF-QRS in patients with myocardial ischemia might be due to the slowing of the conduction velocity in the region of ischemia. This mechanism has been tested by Watanabe et al by infusing sodium channel blockers into the left anterior descending artery in dogs. In their study, 60 unipolar ECGs were recorded from the entire

  3. The frequency of an IL-18-associated haplotype in Africans.

    Science.gov (United States)

    Thompson, Simon R; Humphries, Steve E; Thomas, Mark G; Ekong, Rosemary; Tarekegn, Ayele; Bekele, Endeshaw; Creemer, Olivia; Bradman, Neil; Veeramah, Krishna R

    2013-04-01

    Variation within the gene for the proinflammatory cytokine interleukin (IL)-18 has been associated with inter-individual differences in levels of free protein and disease risk. We investigated the frequency of function-associated IL18 gene haplotypes in an extensive sample (n=2357) of African populations from across the continent. A previously identified five tagging SNP (single-nucleotide polymorphism) haplotype (here designated hGTATA), known to be associated with lower levels of IL-18, was observed at a frequency of 27% in a British population of recent European ancestry, but was found at low frequency (African populations. Potentially protective variants may, as a consequence, be found at low frequency in African individuals and may confer a difference in disease risk.

  4. Arbitrary optical frequency synthesis traced to an optical frequency comb

    Science.gov (United States)

    Cai, Zihang; Zhang, Weipeng; Yang, Honglei; Li, Yan; Wei, Haoyun

    2016-11-01

    An arbitrary optical frequency synthesizer with a broad tuning range and high frequency accuracy is presented. The system includes an external cavity diode laser (ECDL) as the output laser, an Erbium-doped optical frequency comb being a frequency reference, and a control module. The optical frequency from the synthesizer can be continuously tuned by the large-scale trans-tooth switch and the fine intra-tooth adjustment. Robust feedback control by regulating the current and PZT voltage enables the ECDL to phase-lock to the Erbium-doped optical frequency comb, therefore to keep stable frequency output. In the meanwhile, the absolute frequency of the synthesizer is determined by the repetition rate, the offset frequency and the beat frequency. All the phase lock loops in the system are traced back to a Rubidium clock. A powerful and friendly software is developed to make the operation convenient by integrating the functions of frequency setting, tuning, tracing, locking and measuring into a LabVIEW interface. The output frequency tuning span and the uncertainty of the system are evaluated as >6 THz and Ring-Down Spectroscopy.

  5. 北京汉族和西北欧洲后裔人群ROR2基因单核苷酸多态性比较研究%Comparison of MAFs and haplotype frequencies for SNPs in the ROR2 gene of CHB and CEU

    Institute of Scientific and Technical Information of China (English)

    赵凯平; 王红

    2011-01-01

    Objective To provide scientific basis of single nucleotide polymorphism (SNPs) determination for ROR2 gene related etiologic studies in Han Chinese in Beijing (CHB) and Utah residents with Northern and Western European ancestry from the CEPH collection (CEU) populations. Methods SNPs in the ROR2 gene of CHB and CEU were analyzed and compared for minor allele frequencies (MAF), hap-lotype blocks and haplotype frequencies by Haploview program. SNPs were screened for eligibility with the quality control criteria of genotyping call rate>80% , HWE test P>0. 01, gender difference P>0. 05 and MAF>0. 01. Tag SNPs were determined with the criteria of r2 ≥0. 8 and LOD≥3 for pairwised eligible SNPs. Common Tag SNPs in the populations of CHB and CEU were either directly analyzed by Haploview program or calculated by SPSS13. 0 for those highly related independent tag SNPs. Results Among 396 genotyped SNPs in CHB and CEU, 102 (25. 8%) were monotonic and common in both populations. The proportions of common eligible SNPs were 78. 3% (206/263) and 75. 2% (206/274) for the populations of CHB and CEU, respectively. Most common eligible SNPs had common minor alleles (189/206, 91. 7%) and of which, 39. 2% had MAF ratio difference<20%. Among 18 and 14 haplotype blocks identified in 206 common eligible SNPs for CHB and CEU, one haplotype block each was independent, three haplotype blocks were common and the remaining 14 haplotype blocks in CHB were overlapped with the 10 haplotype blocks in CEU. A total of 31 common tag SNPs were determined for the populations of CHB (40.3%, 31/77) and CEU (44.9%, 31/69). Conclusion SNPs in ROR2 gene had common and unique features in terms of allele, MAF, haplotype blocks and haplotype frequencies for CHB and CEU populations.%目的 分析比较北京汉族(CHB)和西北欧洲后裔人群(CEU) ROR2基因单核苷酸多态性(SNPs)和单体域的特征,为两人群病因学研究SNPs的确定和分析提供依据.方法

  6. Negative Feedback Governs Gonadotrope Frequency-Decoding of Gonadotropin Releasing Hormone Pulse-Frequency

    OpenAIRE

    2009-01-01

    The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH) from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta) and follicle-stimulating hormone beta-subunit (FSHbeta). Three mitogen-activated protein kinases, (MAPKs), ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this...

  7. Microwave transistor oscillator frequency tripling

    OpenAIRE

    B. A. Kotserzhynskyi

    2010-01-01

    The frequency tripler state of the art is consided. The oscillator-frequency tripler design is now at the state of scientific research. Microwave companies release the devices of the such structure: oscillator, buffer, amplifier-tripler.

  8. Microwave transistor oscillator frequency tripling

    Directory of Open Access Journals (Sweden)

    B. A. Kotserzhynskyi

    2010-01-01

    Full Text Available The frequency tripler state of the art is consided. The oscillator-frequency tripler design is now at the state of scientific research. Microwave companies release the devices of the such structure: oscillator, buffer, amplifier-tripler.

  9. [Gene pool and gene geography of the USSR population].

    Science.gov (United States)

    Rychkov, Iu G; Balanovskaia, E V

    1992-01-01

    Gene pool and gene geography are discussed from the point of view of their conceptual history beginning from the original concept of A.S. Serebrovskiĭ (1928). Difference between the present-day gene geography and gene geography of gene pool is accentuated: the former only represents a portion of the latter. Historical and territorial integrity of the USSR population gene pool, in conjunction with its huge diversity, is the main problem being analysed by various means of computerized genetic cartography. Coupled with the gene frequency mapping, following methods were also used: mapping of average heterozygosity, of interpopulation differentiation, of principal component scores and mapping of geographical trend for each mapped genetic parameter. The work is based on 100 allelic genes and haplotypes from 30 independent loci studied on the average in 225 local populations. Statistical analysis of gene geographical maps is based on 3975 nodes of regular cartographic net for the USSR territory. The wind rose of systematic changes in the USSR gene pool has three main geographic orientations: W-E, SW-NE and S-N. At the same time, there are only two main systematic forces of gene pool evolution: the force of social history with predominant W-E orientation and the force of natural history with predominant S-N orientation of their actions. The heterozygosity level of gene pool declines strictly in accordance with the resultant in the SW-NE direction.

  10. Frequency doubling crystals

    Science.gov (United States)

    Wang, Francis; Velsko, Stephan P.

    1989-01-01

    A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

  11. Matsubara Frequency Sums

    CERN Document Server

    Kumar, Alok

    2010-01-01

    We cannot use directly the results of zero-temperature at finite temperature, for at finite temperature the average is to be carried over all highly degenerate excited states unlike zero-temperature average is only on unique ground state. One of the formal way to take into account the finite temperature into quantum field theory is due to Matsubara, to replace temporal component of eigenvalues $k_{4}$ by $\\omega_{n}=\\frac{2\\pi n}{\\beta}$ $(\\frac{2\\pi (n+{1/2})}{\\beta})$ with summation over all integer values of $n$. The summation is done with the infinite series expansion of $\\coth (\\pi y)$. With the chemical potential $\\mu$, $\\omega_{n}$ will be replaced by $\\omega_{n} - \\mu$ in the eigenvalues and the summation over $n$ cannot be done easily. Various methods exist to evaluate it. We use the infinite series expansion of $\\coth (\\pi y)$ to work operationally for such Matsubara frequency sums.

  12. Frequency mixing crystal

    Science.gov (United States)

    Ebbers, Christopher A.; Davis, Laura E.; Webb, Mark

    1992-01-01

    In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

  13. High Frequency Oscillatory Ventilation

    Directory of Open Access Journals (Sweden)

    AC Bryan

    1996-01-01

    Full Text Available High frequency oscillatory (HFO ventilation using low tidal volume and peak airway pressures is extremely efficient at eliminating carbon dioxide and raising pH in the newborn infant with acute respiratory failure. Improvement in oxygenation requires a strategy of sustained or repetitive inflations to 25 to 30 cm H2O in order to place the lung on the deflation limb of the pressure-volume curve. This strategy has also been shown to decrease the amount of secondary lung injury in animal models. Experience of the use of HFO ventilation as a rescue therapy as well as several published controlled trials have shown improved outcomes and a decrease in the use of extracorporeal membrane oxygenation when it has been used in newborns.

  14. High frequency nanotube oscillator

    Science.gov (United States)

    Peng, Haibing [Houston, TX; Zettl, Alexander K [Kensington, TX

    2012-02-21

    A tunable nanostructure such as a nanotube is used to make an electromechanical oscillator. The mechanically oscillating nanotube can be provided with inertial clamps in the form of metal beads. The metal beads serve to clamp the nanotube so that the fundamental resonance frequency is in the microwave range, i.e., greater than at least 1 GHz, and up to 4 GHz and beyond. An electric current can be run through the nanotube to cause the metal beads to move along the nanotube and changing the length of the intervening nanotube segments. The oscillator can operate at ambient temperature and in air without significant loss of resonance quality. The nanotube is can be fabricated in a semiconductor style process and the device can be provided with source, drain, and gate electrodes, which may be connected to appropriate circuitry for driving and measuring the oscillation. Novel driving and measuring circuits are also disclosed.

  15. Instantaneous Frequency Attribute Comparison

    Science.gov (United States)

    Yedlin, M. J.; Margrave, G. F.; Ben Horin, Y.

    2013-12-01

    The instantaneous seismic data attribute provides a different means of seismic interpretation, for all types of seismic data. It first came to the fore in exploration seismology in the classic paper of Taner et al (1979), entitled " Complex seismic trace analysis". Subsequently a vast literature has been accumulated on the subject, which has been given an excellent review by Barnes (1992). In this research we will compare two different methods of computation of the instantaneous frequency. The first method is based on the original idea of Taner et al (1979) and utilizes the derivative of the instantaneous phase of the analytic signal. The second method is based on the computation of the power centroid of the time-frequency spectrum, obtained using either the Gabor Transform as computed by Margrave et al (2011) or the Stockwell Transform as described by Stockwell et al (1996). We will apply both methods to exploration seismic data and the DPRK events recorded in 2006 and 2013. In applying the classical analytic signal technique, which is known to be unstable, due to the division of the square of the envelope, we will incorporate the stabilization and smoothing method proposed in the two paper of Fomel (2007). This method employs linear inverse theory regularization coupled with the application of an appropriate data smoother. The centroid method application is straightforward and is based on the very complete theoretical analysis provided in elegant fashion by Cohen (1995). While the results of the two methods are very similar, noticeable differences are seen at the data edges. This is most likely due to the edge effects of the smoothing operator in the Fomel method, which is more computationally intensive, when an optimal search of the regularization parameter is done. An advantage of the centroid method is the intrinsic smoothing of the data, which is inherent in the sliding window application used in all Short-Time Fourier Transform methods. The Fomel technique

  16. Robust power system frequency control

    CERN Document Server

    Bevrani, Hassan

    2014-01-01

    This updated edition of the industry standard reference on power system frequency control provides practical, systematic and flexible algorithms for regulating load frequency, offering new solutions to the technical challenges introduced by the escalating role of distributed generation and renewable energy sources in smart electric grids. The author emphasizes the physical constraints and practical engineering issues related to frequency in a deregulated environment, while fostering a conceptual understanding of frequency regulation and robust control techniques. The resulting control strategi

  17. Frequency mixer having ferromagnetic film

    Energy Technology Data Exchange (ETDEWEB)

    Khitun, Alexander; Roshchin, Igor V.; Galatsis, Kosmas; Bao, Mingqiang; Wang, Kang L.

    2016-03-29

    A frequency conversion device, which may include a radiofrequency (RF) mixer device, includes a substrate and a ferromagnetic film disposed over a surface of the substrate. An insulator is disposed over the ferromagnetic film and at least one microstrip antenna is disposed over the insulator. The ferromagnetic film provides a non-linear response to the frequency conversion device. The frequency conversion device may be used for signal mixing and amplification. The frequency conversion device may also be used in data encryption applications.

  18. Robust power system frequency control

    CERN Document Server

    Bevrani, Hassan

    2008-01-01

    Emphasizes the physical and engineering aspects of the power system frequency control design problem while providing a conceptual understanding of frequency regulation and application of robust control techniques. This book summarizes the author's research outcomes, contributions and experiences with power system frequency regulation.

  19. Haemochromatosis gene frequency in a control and diabetic Irish population.

    LENUS (Irish Health Repository)

    Kirk, L

    2009-03-01

    Hereditary haemochromatosis is inherited in an autosomal recessive manner. Two major mutations have been identified and the condition is emerging as one of the most common recessive mutations among subjects of Northern European descendants.

  20. A population frequency analysis of the FABP2 gene polymorphism ...

    African Journals Online (AJOL)

    salah

    Background: Intestinal fatty acid-binding protein (IFAPB) is expressed only in intestinal ... DNA was extracted from blood samples for genotype analysis. ... in turn affect the lipid metabolism and/ ..... fat oxidation and insulin resistance. J. Clin.

  1. Assignment of circadian function for the Neurospora clock gene frequency

    NARCIS (Netherlands)

    Merrow, Martha; Brunner, Michael; Roenneberg, Till

    1999-01-01

    Circadian clocks consist of three elements: entrainment pathways (inputs), the mechanism generating the rhythmicity (oscillator), and the output pathways that control the circadian rhythms. It is difficult to assign molecular clock components to any one of these elements. Experiments show that input

  2. Research of Frequency Discriminator on Frequency Lock Loops

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Frequency lock loops (FLL) discriminating algorithms for direct-sequence spread-spectrum are discussed. The existing algorithms can't solve the problem of data bit reversal during one pre-detection integral period. And when the initial frequency offset is large, the frequency discriminator can't work normally. To solve these problems, a new FLL discriminating algorithm is introduced. The least-squares discriminator is used in this new algorithm. As the least-squares discriminator has a short process unit period, the corresponding frequency discriminating range is large. And the data bit reversal just influence one process unit period, so the least-squares discriminated result will not be affected. Compared with traditional frequency discriminator, the least-squares algorithm can effectively solve the problem of data bit reversal and can endure larger initial frequency offset.

  3. High spectral purity Kerr frequency comb radio frequency photonic oscillator.

    Science.gov (United States)

    Liang, W; Eliyahu, D; Ilchenko, V S; Savchenkov, A A; Matsko, A B; Seidel, D; Maleki, L

    2015-08-11

    Femtosecond laser-based generation of radio frequency signals has produced astonishing improvements in achievable spectral purity, one of the basic features characterizing the performance of an radio frequency oscillator. Kerr frequency combs hold promise for transforming these lab-scale oscillators to chip-scale level. In this work we demonstrate a miniature 10 GHz radio frequency photonic oscillator characterized with phase noise better than -60 dBc Hz(-1) at 10 Hz, -90 dBc Hz(-1) at 100 Hz and -170 dBc Hz(-1) at 10 MHz. The frequency stability of this device, as represented by Allan deviation measurements, is at the level of 10(-10) at 1-100 s integration time-orders of magnitude better than existing radio frequency photonic devices of similar size, weight and power consumption.

  4. The frequency of β-globin gene haplotypes, α-thalassemia and genetic polymorphisms of methylenetetrahydrofolate reductase, factor V Leiden and prothrombin genes in children with sickle cell disease in Rio de Janeiro, Brazil Frequência dos haplótipos da globina beta, da talassemia alfa e dos polimorfismos genéticos dos genes da metilenotetrahidrofolato redutase, do fator V Leiden e da protrombina em crianças com doença falciforme no Rio de Janeiro, Brasil

    Directory of Open Access Journals (Sweden)

    Isaac L. Silva Filho

    2010-02-01

    Full Text Available A freqüência dos haplótipos beta S e beta C do gene da globina e a prevalência de talassemia alfa e de mutações nos genes da metilenotetrahidrofolato redutase (MTHFR-C677T, do fator V de Leiden e da protrombina (G20210A foi estudada em crianças com doença falciforme do Rio de Janeiro. O haplótipo Bantu foi o mais freqüente (65,9%, 21,2% das crianças (18% heterozigotas e 3% homozigotas apresentam talassemia com mutação alfa 3.7kb, ao contrário da mutação alfa 4.2kb que não foi encontrada. Os alelos 677CT e 677TT da MTHFR foram observados em 20,2% e 4,8%, respectivamente. Os haplótipos Camarões, Árabe-Indiano e Senegal não foram detectados na amostra estudada, bem como mutações no gene do fator V de Leiden e da protrombina. Somente o haplótipo beta C CI foi observado. Esse é o primeiro estudo realizado em uma amostra proveniente do Programa de Triagem Neonatal para Hemoglobinopatias do estado do Rio de Janeiro. Apesar do Rio de Janeiro ser a segunda maior cidade brasileira e seus habitantes expressarem o elevado grau de miscigenação ocorrida no país, nossos resultados ainda coincidem com os registros históricos dos fluxos migratórios do gene beta S para o Brasil, bem como refletem a forte influência de indivíduos de origem africana na população do Rio de Janeiro.

  5. Gene targeting with retroviral vectors

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J.; Bernstein, A. (Toronto Univ., ON (Canada))

    1989-04-01

    The authors have designed and constructed integration-defective retroviral vectors to explore their potential for gene targeting in mammalian cells. Two nonoverlapping deletion mutants of the bacterial neomycin resistance (neo) gene were used to detect homologous recombination events between viral and chromosomal sequences. Stable neo gene correction events were selected at a frequency of approximately 1 G418/sup r/ cell per 3 x 10/sup 6/ infected cells. Analysis of the functional neo gene in independent targeted cell clones indicated that unintegrated retroviral linear DNA recombined with the target by gene conversion for variable distances into regions of nonhomology. In addition, transient neo gene correction events which were associated with the complete loss of the chromosomal target sequences were observed. These results demonstrated that retroviral vectors can recombine with homologous chromosomal sequences in rodent and human cells.

  6. Resonance frequency in ferromagnetic superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Qiu Rongke; Huang Andong [School of Science, Shenyang University of Technology, Shenyang 110870 (China); Li Da; Zhang Zhidong, E-mail: rkqiu@163.com [Shenyang National Laboratory for Materials Science, Institute of Metal Research and International Centre for Materials Physics, Chinese Academy of Sciences, Shenyang 110016 (China)

    2011-10-19

    The resonance frequency in two-layer and three-layer ferromagnetic superlattices is studied, using the Callen's Green function method, the Tyablikov decoupling approximation and the Anderson-Callen decoupling approximation. The effects of interlayer exchange coupling, anisotropy, external magnetic field and temperature on the resonance frequency are investigated. It is found that the resonance frequencies increase with increasing external magnetic field. In a parameter region of the asymmetric system, each sublayer corresponds to its own resonance frequency. The anisotropy of a sublayer affects only the resonance frequency corresponding to this sublayer. The stronger the anisotropy, the higher is the resonance frequency. The interlayer exchange coupling affects only the resonance frequencies belonging to the sublayers connected by it. The stronger the interlayer exchange coupling, the higher are the resonance frequencies. All the resonance frequencies decrease as the reduced temperature increases. The results direct the method to enhance and adjust the resonance frequency of magnetic multilayered materials with a wide band.

  7. Digital frequency control of satellite frequency standards. [Defense Navigation Satellites

    Science.gov (United States)

    Nichols, S. A.

    1973-01-01

    In the Frequency and Time Standard Development Program of the TIMATION System, a new miniaturized rubidium vapor frequency standard has been tested and analyzed for possible use on the TIMATION 3A launch, as part of the Defense Navigation Satellite Development Program. The design and construction of a digital frequency control was required to remotely control this rubidium vapor frequency standard as well as the quartz oscillator in current use. This control must be capable of accepting commands from a satellite telemetry system, verify that the correct commands have been sent and control the frequency to the requirements of the system. Several modifications must be performed to the rubidium vapor frequency standard to allow it to be compatible with the digital frequency control. These include the addition of a varactor to voltage tune the coarse range of the flywheel oscillator, and a modification to supply the C field current externally. The digital frequency control for the rubidium vapor frequency standard has been successfully tested in prototype form.

  8. Allelic frequency of G380A polymorphism of tumor necrosis factor alpha gene and relation with cardiovascular risk factors and adipocytokines in obese patients Frecuencia alélica del polimorfismo G380A del factor de necrosis tumoral alpha y relación con factores de riesgo cardiovascular y adipocitoquinas en pacientes obesos

    Directory of Open Access Journals (Sweden)

    D. A. De Luis

    2011-08-01

    Full Text Available Background: The aim of our study was to investigate the allelic frequency of the G308A polymorphism in the TNF alpha gene and the influence of G308A this polymorphism on cardiovascular risk factors and adipokine levels in obese patients. Design: A population of 834 obesity patients was analyzed. A nutritional evaluation and a blood analysis were performed. The statistical analysis was performed for the combined G308A and A308A as mutant group and type G308G as wild group. Results: A total of 630 patients (181 males/449 females (75.5% had the genotype G308/G308 (wild genotype group with an average age of 43.5 ± 14.8 years, 188 patients (61 males/127 females (22.5% had the genotype G308/A308 (mutant genotype group-heterozygote and 16 patients (5 males/11 females (1.9% with an average age of 44.5 ± 14.2 years had the genotype A308/A308 (mutant group-homorozygote with an average age of 44.3 ± 11.4 years, without statistical differences in the mean age or sex distribution. Genotypes G308/A308 and A308/A308 was designed (mutant genotype group as a dominant model. Allelic frequency of the A substitucion -308 was 13.19%. Anthropometric, adipokines, insulin resistance, lipid levels ad dietary intake were similar in both genotypes. Conclusion: In conclusion, allelic frequency of G308A polymorphism is is in accordance with allelic frequencies observed in other populations. Carries of A308 allele have the same anthropometric and metabolic profile than wild type carriers.Antecedentes: El objetivo de nuestro estudio fue investigar la frecuencia alélica del polimorfismo G308A del gen TNF alfa y su influencia en los factores de riesgo cardiovascular y los niveles de adipocinas en pacientes obesos. Diseño: Se estudió una población de 834 pacientes obesos. Se realizaron una evaluación nutricional y un análisis de sangre. El análisis estadístico se realizó para el genotipo combinado G308A y A308A como grupo de mutantes y G308G tipo de grupo salvaje

  9. 低频超声联合微泡促进脂质体介导的人前列腺癌细胞野生型 P53基因转染的实验研究%Low frequency ultrasound combined with microbubbles to promote the transfection of wild-type P53 gene in human prostate cancer cells mediated by liposome

    Institute of Scientific and Technical Information of China (English)

    白文坤; 张蔚; 胡兵

    2015-01-01

    目的:研究低频超声联合微泡在促进脂质体介导的人前列腺癌细胞野生型 P53基因转染中的作用。方法选用频率为21 kHz,功率为46 mW/cm2的低频超声,占空比2∶8(开2 s,停8 s),辐照人前列腺癌 PC-3细胞5 min。PC-3细胞制成细胞悬液,调整细胞浓度为1×105个/ml,细胞分为8组:对照组、单独微泡组、单独超声组、超声联合微泡组、单独脂质体组、脂质体联合微泡组、脂质体联合超声组、脂质体联合超声及微泡组。每微泡组加入常规配置的声诺维200μl,每组均加入野生型 P53质粒,质粒与脂质体比为1∶2。辐照后继续培养24 h,荧光定量及 western-blot 检测基因转染效率,CCK-8检测细胞 OD值,计算细胞存活率,流式细胞仪检测细胞凋亡。结果转染后脂质体联合超声及微泡组较单独脂质体组及对照组能够明显提高人野生型 P53基因及蛋白的表达,差异均有统计学意义(P <0.001)。转染后脂质体联合超声及微泡组较单独脂质体组及对照组明显提高人前列腺癌 PC-3细胞凋亡率,差异均有统计学意义(P <0.001),并且转染后脂质体联合超声、微泡组较单独脂质体组及对照组细胞存活明显受抑制,差异均有统计学意义(P <0.001)。结论低频低能量超声联合微泡能够促进脂质体介导的人野生型 P53基因的转染。%Objective To study low frequency ultrasound combined with microbubbles to promote the transfection of P53 gene in human prostate cancer cells mediated by liposome.Methods Ultrasound equipment was used with a frequency of 21 kHz and intensity was 46 mW/cm2 and the working time was controlled at 20% (i.e.,2 s “on”time and 8 s “off”time)lasting 5 minutes.The human prostate cancer cell line PC-3 suspension was prepared,the cell concentration was adjusted to 1 × 10 5 cell/ ml,and cells were divided into 8 groups:control group,single microbubbles group,single ultrasound group

  10. Counting Frequencies from Zotero Items

    Directory of Open Access Journals (Sweden)

    Spencer Roberts

    2013-04-01

    Full Text Available In Counting Frequencies you learned how to count the frequency of specific words in a list using python. In this lesson, we will expand on that topic by showing you how to get information from Zotero HTML items, save the content from those items, and count the frequencies of words. It may be beneficial to look over the previous lesson before we begin.

  11. Counting Word Frequencies with Python

    Directory of Open Access Journals (Sweden)

    William J. Turkel

    2012-07-01

    Full Text Available Your list is now clean enough that you can begin analyzing its contents in meaningful ways. Counting the frequency of specific words in the list can provide illustrative data. Python has an easy way to count frequencies, but it requires the use of a new type of variable: the dictionary. Before you begin working with a dictionary, consider the processes used to calculate frequencies in a list.

  12. Frequency Resonance in Stochastic Systems

    Institute of Scientific and Technical Information of China (English)

    钱敏; 张雪娟

    2003-01-01

    The phenomenon of frequency resonance, which is usually related to deterministic systems, is investigated in stochastic systems. We show that for those autonomous systems driven only by white noise, if the output power spectrum exhibits a nonzero peak frequency, then applying a periodic signel just on this noise-induced central frequency can also induce a resonance phenomenon, which we call the frequency stochastic resonance. The effect of such a resonance in a coupled stochastic system is shown to be much better than that in a single-oscillator system.

  13. Mixed Frequency Ultrasound Phased Array

    Institute of Scientific and Technical Information of China (English)

    香勇; 霍健; 施克仁; 陈以方

    2004-01-01

    A mixed frequency ultrasonic phased array (MPA) was developed to improve the focus, in which the element excitation frequencies are not all the same as in a normal constant frequency phased array. A theoretical model of the mixed frequency phased array based on the interference principle was used to simulate the array's sound distribution. The pressure intensity in the array focal area was enhanced and the scanning area having effective contrast resolution was enlarged. The system is especially useful for high intensity focused ultrasound (HIFU) with more powerful energy and ultrasound imaging diagnostics with improved signal to noise ratios, improved beam forming and more uniform imaging quality.

  14. Radio Frequency Anechoic Chamber Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Supports the design, manufacture, and test of antenna systems. The facility is also used as an electromagnetic compatibility/radio frequency interference...

  15. Lexical frequency and voice assimilation.

    Science.gov (United States)

    Ernestus, Mirjam; Lahey, Mybeth; Verhees, Femke; Baayen, R Harald

    2006-08-01

    Acoustic duration and degree of vowel reduction are known to correlate with a word's frequency of occurrence. The present study broadens the research on the role of frequency in speech production to voice assimilation. The test case was regressive voice assimilation in Dutch. Clusters from a corpus of read speech were more often perceived as unassimilated in lower-frequency words and as either completely voiced (regressive assimilation) or, unexpectedly, as completely voiceless (progressive assimilation) in higher-frequency words. Frequency did not predict the voice classifications over and above important acoustic cues to voicing, suggesting that the frequency effects on the classifications were carried exclusively by the acoustic signal. The duration of the cluster and the period of glottal vibration during the cluster decreased while the duration of the release noises increased with frequency. This indicates that speakers reduce articulatory effort for higher-frequency words, with some acoustic cues signaling more voicing and others less voicing. A higher frequency leads not only to acoustic reduction but also to more assimilation.

  16. Broadband antenna with frequency scanning

    Directory of Open Access Journals (Sweden)

    A. A. Shekaturin

    2014-06-01

    Full Text Available Relevance of this study. The main advantage of frequency scanning is simplicity of implementation. At this point, multifunctional usage of microwave modules is an urgent task, as well as their maximum simpler and cheaper. Antenna design and operation. The study is aimed at providing electric antenna with frequency scanning. It was based on the log-periodic antenna due to its wideband and negotiation capability over the entire operating frequency range. For this distribution line is bent in an arc of a circle in a plane blade while vibrators are arranged along the radius. Computer modeling of antennas with frequency scanning. Modeled with a non-mechanical motion antenna beam emitters representing system for receiving a radio frequency signal on mobile objects calculated for 1.8 GHz ... 4.2 GHz. The simulation was performed in a software environment for numerical modeling of electromagnetic «Feko 5.5». Analysis of the interaction of radiation is based on the method of moments. Findings. The result of this work is to propose a new design of the antenna with a frequency scanning method as agreed in a wide frequency range. In the studied technical solution provided by the rotation of NAM in the frequency range, and the matching of the antenna to the feed line is maintained. Application of this type of antennas on the proposed technical solution in communication systems will improve the communication reliability by maintaining coordination in the frequency range

  17. Frequency hopping millimeter wave reflectometer

    Science.gov (United States)

    Cupido, L.; Sánchez, J.; Estrada, T.

    2004-10-01

    Reflectometry techniques are employed to study density fluctuations in fusion plasmas either using one channel or two channels with slightly different frequencies, to probe simultaneously closely spaced plasma layers (for radial correlation studies). The present article describes a novel system with increasing measuring capability utilizing only one single frequency that can be hopped during the discharge. This broadband fast hopping mm-wave reflectometer (BFHR) has been developed for both ASDEX upgrade (Max Plank Institute-Garching-Germany) and TJ-II stellarator (CIEMAT-Spain). The BFHR incorporates frequency synthesizers at microwave frequencies multiplied into the millimeter-wave range and uses heterodyne detection for sensitive phase and amplitude measurements.

  18. Automatic oscillator frequency control system

    Science.gov (United States)

    Smith, S. F. (Inventor)

    1985-01-01

    A frequency control system makes an initial correction of the frequency of its own timing circuit after comparison against a frequency of known accuracy and then sequentially checks and corrects the frequencies of several voltage controlled local oscillator circuits. The timing circuit initiates the machine cycles of a central processing unit which applies a frequency index to an input register in a modulo-sum frequency divider stage and enables a multiplexer to clock an accumulator register in the divider stage with a cyclical signal derived from the oscillator circuit being checked. Upon expiration of the interval, the processing unit compares the remainder held as the contents of the accumulator against a stored zero error constant and applies an appropriate correction word to a correction stage to shift the frequency of the oscillator being checked. A signal from the accumulator register may be used to drive a phase plane ROM and, with periodic shifts in the applied frequency index, to provide frequency shift keying of the resultant output signal. Interposition of a phase adder between the accumulator register and phase plane ROM permits phase shift keying of the output signal by periodic variation in the value of a phase index applied to one input of the phase adder.

  19. Numeracy, frequency, and Bayesian reasoning

    Directory of Open Access Journals (Sweden)

    Gretchen B. Chapman

    2009-02-01

    Full Text Available Previous research has demonstrated that Bayesian reasoning performance is improved if uncertainty information is presented as natural frequencies rather than single-event probabilities. A questionnaire study of 342 college students replicated this effect but also found that the performance-boosting benefits of the natural frequency presentation occurred primarily for participants who scored high in numeracy. This finding suggests that even comprehension and manipulation of natural frequencies requires a certain threshold of numeracy abilities, and that the beneficial effects of natural frequency presentation may not be as general as previously believed.

  20. A graphene based frequency quadrupler

    Science.gov (United States)

    Cheng, Chuantong; Huang, Beiju; Mao, Xurui; Zhang, Zanyun; Zhang, Zan; Geng, Zhaoxin; Xue, Ping; Chen, Hongda

    2017-04-01

    Benefit from exceptional electrical transport properties, graphene receives worldwide attentions, especially in the domain of high frequency electronics. Due to absence of effective bandgap causing off-state the device, graphene material is extraordinarily suitable for analog circuits rather than digital applications. With this unique ambipolar behavior, graphene can be exploited and utilized to achieve high performance for frequency multipliers. Here, dual-gated graphene field-effect transistors have been firstly used to achieve frequency quadrupling. Two Dirac points in the transfer curves of the designed GFETs can be observed by tuning top-gate voltages, which is essential to generate the fourth harmonic. By applying 200 kHz sinusoid input, arround 50% of the output signal radio frequency power is concentrated at the desired frequency of 800 kHz. Additionally, in suitable operation areas, our devices can work as high performance frequency doublers and frequency triplers. Considered both simple device structure and potential superhigh carrier mobility of graphene material, graphene-based frequency quadruplers may have lots of superiorities in regards to ultrahigh frequency electronic applications in near future. Moreover, versatility of carbon material system is far-reaching for realization of complementary metal-oxide-semiconductor compatible electrically active devices.

  1. Frequency dependent polarization analysis of high-frequency seismograms

    Science.gov (United States)

    Park, Jeffrey; Vernon, Frank L., III; Lindberg, Craig R.

    1987-11-01

    We present a multitaper algorithm to estimate the polarization of particle motion as a function of frequency from three-component seismic data. This algorithm is based on a singular value decomposition of a matrix of eigenspectra at a given frequency. The right complex eigenvector zˆ corresonding to the largest singular value of the matrix has the same direction as the dominant polarization of seismic motion at that frequency. The elements of the polarization vector zˆ specify the relative amplitudes and phases of motion measured along the recorded components within a chosen frequency band. The width of this frequency band is determined by the time-bandwidth product of the prolate spheroidal tapers used in the analysis. We manipulate the components of zˆ to determine the apparent azimuth and angle of incidence of seismic motion as a function of frequency. The orthogonality of the eigentapers allows one to calculate easily uncertainties in the estimated azimuth and angle of incidence. We apply this algorithm to data from the Anza Seismic Telemetered Array in the frequency band 0 ≤ ƒ ≤ 30 Hz. The polarization is not always a smooth function of frequency and can exhibit sharp jumps, suggesting the existence of scattered modes within the crustal waveguide and/or receiver site resonances.

  2. Absolute frequency measurement of unstable lasers with optical frequency combs

    Science.gov (United States)

    Beverini, N.; Poli, N.; Sutyrin, D.; Wang, F.-Y.; Schioppo, M.; Tarallo, M. G.; Tino, G. M.

    2010-09-01

    Here we report on absolute frequency measurements of a commercial high power CW diode-pumped solid-state laser (Coherent Verdi-V5). This kind of lasers usually presents large frequency jitter (up to 50 MHz) both in the short term (1 ms time scale) and in the long term (>10 s time scale). A precise measurement of absolute frequency deviations in both temporal scales should require a set of different devices (optical cavities, optical wave-meters), each suited for measurements only at a specific integration time. Here we demonstrate how a frequency comb can be used to overcome this difficulty, allowing in a single step a full characterization of both short ( 103 s) absolute frequency jitter with a resolution better than 1 MHz. We demonstrate in this way the flexibility of optical frequency combs for absolute frequency measurements not only of ultra-stable lasers but also of relatively unstable lasers. The absolute frequency calibration of the Verdi laser that we have obtained have been used in order to improve the accuracy of the measurements of the local gravitational acceleration value with 88Sr atoms trapped in 1D vertical lattices.

  3. Behavioral estimates of human frequency selectivity at low frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado

    A fundamental property of our hearing organ is its ability to break down sound into different spectral components, allowing us to make use of the richness in natural sound phenomena. Auditory filters, which conceptualize this property of the ear, however, have not been appropriately described...... at low sound frequencies. As a consequence of our lack of knowledge, we cannot accurately model our perception of complex low-frequency sound (such as that emitted by wind turbines or industrial processes, which can easily produce annoyance) nor make meaningful predictions of our perception based...... on physical sound measurements. In this PhD thesis a detailed description of frequency selectivity at low frequencies is given. Different experiments have been performed to determine the properties of human auditory filters. Besides, loudness perception of low-frequency sinusoidal signals has been evaluated...

  4. Low-frequency-noise complaints

    DEFF Research Database (Denmark)

    Pedersen, Christian Sejer; Møller, Henrik; Persson-Waye, Kerstin

    2008-01-01

    From 203 cases of low-frequency complaints a random selection of twenty-one cases were investigated. The main aim of the investigation was to answer the question whether the annoyance is caused by an external physical sound or by a physically non-existing sound, i.e. low-frequency tinnitus. Noise...... of the complainants are annoyed by a physical sound (20-180 Hz), while others suffer from low-frequency tinnitus (perceived frequency 40-100 Hz). Physical sound at frequencies below 20 Hz (infrasound) is not responsible for the annoyance - or at all audible - in any of the investigated cases, and none...... of the complainants has extraordinary hearing sensitivity at low frequencies. For comparable cases of low-frequency noise complaints in general, it is anticipated that physical sound is responsible in a substantial part of the cases, while low-frequency tinnitus is responsible in another substantial part of the cases....

  5. Gaming Frequency and Academic Performance

    Science.gov (United States)

    Ip, Barry; Jacobs, Gabriel; Watkins, Alan

    2008-01-01

    There are numerous claims that playing computer and video games may be educationally beneficial, but there has been little formal investigation into whether or not the frequency of exposure to such games actually affects academic performance. This paper explores the issue by analysing the relationships between gaming frequency--measured as the…

  6. Frequency conversion of structured light.

    Science.gov (United States)

    Steinlechner, Fabian; Hermosa, Nathaniel; Pruneri, Valerio; Torres, Juan P

    2016-02-15

    Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.

  7. Frequency Sensitivity in Nervous Systems

    Institute of Scientific and Technical Information of China (English)

    LIU Feng; WANG Wei

    2001-01-01

    We first demonstrate how to quantify the information conveyed in temporal firing patterns of neurons. We then show that neurons are more sensitive to signals with frequencies within the range of 20 - 70 Hz in weak signal detection. Such frequency sensitivity is characterized by both the output signal-to-noise ratio and the information measures.

  8. A variable frequency semiconductor laser

    Energy Technology Data Exchange (ETDEWEB)

    Tosikhiro, F.; Khiromoto, S.

    1984-03-27

    A variable frequency, power stabilized semiconductor laser is patented. This laser includes, in addition to an active layer, a photoconducting channel layer and a layer made from a material manifesting a Pockels effect. A voltage is injected between these two layers to vary the emission frequency. The laser pumping voltage is stabilized.

  9. Lexical Frequency in Sign Languages

    Science.gov (United States)

    Johnston, Trevor

    2012-01-01

    Measures of lexical frequency presuppose the existence of corpora, but true machine-readable corpora of sign languages (SLs) are only now being created. Lexical frequency ratings for SLs are needed because there has been a heavy reliance on the interpretation of results of psycholinguistic and neurolinguistic experiments in the SL research…

  10. Frequency-controlled voltage regulator

    Science.gov (United States)

    Mclyman, W. T.

    1980-01-01

    Converting input ac to higher frequency reduce size and weight and makes possible unique kind of regulation. Since conversion frequency is above range of human hearing, supply generated on audible noise. It also exploits highfrequency conversion features to regulate its output voltage in novel way. Circuit is inherently short-circuit proof.

  11. Low-frequency ac electroporation shows strong frequency dependence and yields comparable transfection results to dc electroporation.

    Science.gov (United States)

    Zhan, Yihong; Cao, Zhenning; Bao, Ning; Li, Jianbo; Wang, Jun; Geng, Tao; Lin, Hao; Lu, Chang

    2012-06-28

    Conventional electroporation has been conducted by employing short direct current (dc) pulses for delivery of macromolecules such as DNA into cells. The use of alternating current (ac) field for electroporation has mostly been explored in the frequency range of 10kHz-1MHz. Based on Schwan equation, it was thought that with low ac frequencies (10Hz-10kHz), the transmembrane potential does not vary with the frequency. In this report, we utilized a flow-through electroporation technique that employed continuous 10Hz-10kHz ac field (based on either sine waves or square waves) for electroporation of cells with defined duration and intensity. Our results reveal that electropermeabilization becomes weaker with increased frequency in this range. In contrast, transfection efficiency with DNA reaches its maximum at medium frequencies (100-1000Hz) in the range. We postulate that the relationship between the transfection efficiency and the ac frequency is determined by combined effects from electrophoretic movement of DNA in the ac field, dependence of the DNA/membrane interaction on the ac frequency, and variation of transfection under different electropermeabilization intensities. The fact that ac electroporation in this frequency range yields high efficiency for transfection (up to ~71% for Chinese hamster ovary cells) and permeabilization suggests its potential for gene delivery.

  12. Laser Spectroscopy and Frequency Combs

    Science.gov (United States)

    Hänsch, Theodor W.; Picqué, Nathalie

    2013-12-01

    The spectrum of a frequency comb, commonly generated by a mode-locked femtosecond laser consists of several hundred thousand precisely evenly spaced spectral lines. Such laser frequency combs have revolutionized the art measuring the frequency of light, and they provide the long-missing clockwork for optical atomic clocks. The invention of the frequency comb technique has been motivated by precision laser spectroscopy of the simple hydrogen atom. The availability of commercial instruments is facilitating the evolution of new applications far beyond the original purpose. Laser combs are becoming powerful instruments for broadband molecular spectroscopy by dramatically improving the resolution and recording speed of Fourier spectrometers and by creating new opportunities for highly multiplexed nonlinear spectroscopy, such as two-photon spectroscopy or coherent Raman spectroscopy. Other emerging applications of frequency combs range from fundamental research in astronomy, chemistry, or attosecond science to telecommunications and satellite navigation.

  13. Frequency conversion of structured light

    CERN Document Server

    Steinlechner, Fabian; Pruneri, Valerio; Torres, Juan P

    2015-01-01

    We demonstrate the coherent frequency conversion of structured light, optical beams in which the phase varies in each point of the transverse plane, from the near infrared (803nm) to the visible (527nm). The frequency conversion process makes use of sum-frequency generation in a periodically poled lithium niobate (ppLN) crystal with the help of a 1540-nm Gaussian pump beam. We perform far-field intensity measurements of the frequency-converted field, and verify the sought-after transformation of the characteristic intensity and phase profiles for various input modes. The coherence of the frequency-conversion process is confirmed using a mode-projection technique with a phase mask and a single-mode fiber. The presented results could be of great relevance to novel applications in high-resolution microscopy and quantum information processing.

  14. 高频超声心动图评估Bax基因转染对大鼠异位移植心脏存活的影响%Assessment of Bax gene transfer influence on survival of heterotopic cardiac allograft in rats by high-frequency echocardiography

    Institute of Scientific and Technical Information of China (English)

    金佳美; 张宇辉; 陈明; 朱烨; 曹浩

    2013-01-01

    目的 探讨高频超声心动图在评估Bax基因转染对大鼠异位移植心脏存活影响中的价值.方法 建立30只腹腔同种异体心脏移植大鼠模型,分为3组,每组10只:A组,单纯移植组;B组,供心移植+抗排异反应药物组;C组,供心移植+ Bax-shRNA+超声微泡组.大鼠分别于心脏移植手术后第1、3、6d,采用高频超声心动图测量大鼠左室舒张末期内径(LVIDd)、左室收缩末期内径(LVIDs)、左室射血分数(LVEF)、左室心肌厚度(LVT)、左室心肌增厚率(LVTR)等参数,于术后第6d超声测量完毕后处死5只大鼠取心肌组织行病理检查,其余5只大鼠用于观察移植心脏存活时间.结果 ①高频超声心动图能清晰显示大鼠移植心脏常规切面;②C组移植心脏存活时间为(16.21±5.01)d,明显长于B组[(11.14±1.72)d,P<0.05]及A组[(7.26±1.57)d,P<0.01].③移植术后,三组大鼠左室心肌厚度逐渐增加;术后第6d,A组LVEF明显低于B组及C组(P<0.05),而B组与C组间差异无统计学意义(P>0.05);术后第3、6d,A组及B组LVT高于C组(P<0.05),LVTR低于C组(P<0.05).结论 高频超声心动图能准确评价Bax基因转染对大鼠移植心脏存活的影响,判断移植心脏结构和功能,其中LVT及LVTR较LVEF更为敏感,可作为早期评估指标.%Objective To evaluate the value of high-frequency echocardiography in assessing Bax gene transfer influence on survival of heterotopic cardiac allograft in rats.Methods Thirty rat models of heterotopic heart transplantation were established.Group A received heart transplantation only; Group B received cyclosporin (CsA) after operatiom Group C received ultrasound targeted microbubble destruction (UTMD) combined with Bax-shRNA.All rats were tested by high-frequency echocardiography at day 1,3,6 after transplantation.The ultrasound parameters included left ventricular internal dimension diastole (LVIDd),left ventricular internal dimension systole(LVIDs),left ventricular

  15. Intermittency and transient chaos from simple frequency-dependent selection.

    Science.gov (United States)

    Gavrilets, S; Hastings, A

    1995-08-22

    Frequency-dependent selection is an important determinant of the evolution of gametophytic self-incompatibility systems in plants, aposematic (warning) and cryptic coloration, systems of mimicry, competitive interactions among members of a population, mating preferences, predator-prey and host-parasite interactions, aggression and other behavioural traits. Past theoretical studies of frequency-dependent selection have shown it to be a plausible mechanism for the maintenance of genetic variability in natural populations. Here, through an analysis of a simple deterministic model for frequency-dependent selection, we demonstrate that complex dynamic behaviour is possible under a broad range of parameter values. In particular we show that the model exhibits not only cycles and chaos but also, for a more restricted set of parameters, transient chaos and intermittency: alterations between an apparently deterministic behaviour and apparently chaotic fluctuations. This behaviour, which has not been stressed within the population genetics literature, provides an explanation for erratic dynamics of gene frequencies.

  16. CHEK2 1100DELC germline mutation: a frequency study in hereditary breast and colon cancer Brazilian families Mutação germinativa 1100delC no gene CHEK2: estudo da frequência em famílias brasileiras com câncer de mama e cólon hereditários

    Directory of Open Access Journals (Sweden)

    Jamile Abud

    2012-12-01

    Full Text Available CONTEXT: CHEK2 encodes a cell cycle checkpoint kinase that plays an important role in the DNA damage repair pathway, activated mainly by ATM (Ataxia Telangiectasia Mutated in response to double-stranded DNA breaks. A germline mutation in CHEK2, 1100delC, has been described as a low penetrance allele in a significant number of families with breast and colorectal cancer in certain countries and is also associated with increased risk of contralateral breast cancer in women previously affected by the disease. About 5%-10% of all breast and colorectal cancers are associated with hereditary predisposition and its recognition is of great importance for genetic counseling and cancer risk management. OBJECTIVES: Here, we have assessed the frequency of the CHEK2 1100delC mutation in the germline of 59 unrelated Brazilian individuals with clinical criteria for the hereditary breast and colorectal cancer syndrome. METHODS: A long-range PCR strategy followed by gene sequencing was used. RESULTS: The 1100delC mutation was encountered in the germline of one (1.7% individual in this high risk cohort. This indicates that the CHEK2 1100delC is not commonly encountered in Brazilian families with multiple diagnoses of breast and colorectal cancer. CONCLUSION: These results should be confirmed in a larger series of families and further testing should be undertaken to investigate the molecular mechanisms underlying the hereditary breast and colorectal cancer phenotype.INTRODUÇÃO: CHEK2 codifica uma proteína quinase envolvida em um ponto de checagem do ciclo celular que desempenha um papel importante na via de reparação do DNA, danos ativados principalmente por ATM (Ataxia Telangiectasia Mutado em resposta a danos na dupla hélice do DNA. A mutação germinativa 1100delC no gene CHEK2 tem sido descrita como um alelo de baixa penetrância em um número significativo de famílias com câncer de mama e cólon em certos países e também está associada com risco

  17. Acoustic resonance frequency locked photoacoustic spectrometer

    Science.gov (United States)

    Pilgrim, Jeffrey S.; Bomse, David S.; Silver, Joel A.

    2003-09-09

    A photoacoustic spectroscopy method and apparatus for maintaining an acoustic source frequency on a sample cell resonance frequency comprising: providing an acoustic source to the sample cell, the acoustic source having a source frequency; repeatedly and continuously sweeping the source frequency across the resonance frequency at a sweep rate; and employing an odd-harmonic of the source frequency sweep rate to maintain the source frequency sweep centered on the resonance frequency.

  18. Frequency-Locking in Coupled Chaotic Systems

    Institute of Scientific and Technical Information of China (English)

    HU Bam-Bi; LIU Zong-Hua; ZHENG Zhi-Gang

    2001-01-01

    A novel approach is presented for measuring the phase synchronization (frequency-locking) of coupled N nonidentical oscillators, which can characterize frequency-locking for chaotic systems without well-defined phase by measuring the mean frequency. Numerical simulations confirm the existence of frequency-locking. The relations between the mean frequency and the coupling strength and the frequency mismatch are given. For the coupled hyperchaotic systems, the frequency-locking can be better characterized by more than one mean frequency curves.

  19. The relationship among gene expression, the evolution of gene dosage, and the rate of protein evolution.

    Directory of Open Access Journals (Sweden)

    Jean-François Gout

    2010-05-01

    Full Text Available The understanding of selective constraints affecting genes is a major issue in biology. It is well established that gene expression level is a major determinant of the rate of protein evolution, but the reasons for this relationship remain highly debated. Here we demonstrate that gene expression is also a major determinant of the evolution of gene dosage: the rate of gene losses after whole genome duplications in the Paramecium lineage is negatively correlated to the level of gene expression, and this relationship is not a byproduct of other factors known to affect the fate of gene duplicates. This indicates that changes in gene dosage are generally more deleterious for highly expressed genes. This rule also holds for other taxa: in yeast, we find a clear relationship between gene expression level and the fitness impact of reduction in gene dosage. To explain these observations, we propose a model based on the fact that the optimal expression level of a gene corresponds to a trade-off between the benefit and cost of its expression. This COSTEX model predicts that selective pressure against mutations changing gene expression level or affecting the encoded protein should on average be stronger in highly expressed genes and hence that both the frequency of gene loss and the rate of protein evolution should correlate negatively with gene expression. Thus, the COSTEX model provides a simple and common explanation for the general relationship observed between the level of gene expression and the different facets of gene evolution.

  20. Negative feedback governs gonadotrope frequency-decoding of gonadotropin releasing hormone pulse-frequency.

    Directory of Open Access Journals (Sweden)

    Stefan Lim

    Full Text Available The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta and follicle-stimulating hormone beta-subunit (FSHbeta. Three mitogen-activated protein kinases, (MAPKs, ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R. Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.

  1. Negative feedback governs gonadotrope frequency-decoding of gonadotropin releasing hormone pulse-frequency.

    Science.gov (United States)

    Lim, Stefan; Pnueli, Lilach; Tan, Jing Hui; Naor, Zvi; Rajagopal, Gunaretnam; Melamed, Philippa

    2009-09-29

    The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH) from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta) and follicle-stimulating hormone beta-subunit (FSHbeta). Three mitogen-activated protein kinases, (MAPKs), ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R). Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.

  2. Frequency domain processing of on-chip biphoton frequency comb

    CERN Document Server

    Jaramillo-Villegas, Jose A; Odele, Ogaga D; Leaird, Daniel E; Ou, Zhe-Yu; Qi, Minghao; Weiner, Andrew M

    2016-01-01

    Quantum information processing (QIP) promises to improve the security of our communications as well as to solve some algorithms with exponential complexity in polynomial time. Biphotons have been demonstrated as one of the most promising platforms for real implementations of QIP systems. In particular, time-bin entangled photons have been used for implementations of quantum gates which require highly stable interferometers. On the other hand, frequency-bin entanglement has been proposed to avoid the use of interferometers and the complexity of their stabilization, which potentially makes the implementation of quantum gates highly scalable. Through Fourier transform pulse shaping and electro-optic modulation, there has been a wide range of experiments that show control of entangled photons in the frequency domain. In addition, biphoton frequency combs (BFC) have also been generated using bulk optics and frequency filtering of broadband continuous biphoton spectra. However, on-chip entangled photon pair generat...

  3. Monolithically integrated absolute frequency comb laser system

    Energy Technology Data Exchange (ETDEWEB)

    Wanke, Michael C.

    2016-07-12

    Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.

  4. Gene therapy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    2005147 CNHK200-hA-a gene-viral therapeutic system and its antitumor effect on lung cancer. WANG Wei-guo(王伟国),et al. Viral & Gene Ther Center, Eastern Hepatobilli Surg Instit 2nd Milit Univ, Shanghai 200438. Chin J Oncol,2005:27(2):69-72. Objective: To develop a novel vector system, which combines the advantages of the gene therapy,

  5. High-frequency magnetic components

    CERN Document Server

    Kazimierczuk, Marian K

    2009-01-01

    If you are looking for a complete study of the fundamental concepts in magnetic theory, read this book. No other textbook covers magnetic components of inductors and transformers for high-frequency applications in detail. This unique text examines design techniques of the major types of inductors and transformers used for a wide variety of high-frequency applications including switching-mode power supplies (SMPS) and resonant circuits. It describes skin effect and proximity effect in detail to provide you with a sound understanding of high-frequency phenomena. As well as this, you will disco

  6. Frequency synthesizers concept to product

    CERN Document Server

    Chenakin, Alexander

    2011-01-01

    A frequency synthesizer is an electronic system for generating any of a range of frequencies from a single fixed oscillator. They are found in modern devices like radio receivers, mobile phones, and GPS systems. This comprehensive resource offers RF and microwave engineers a thorough overview of both well-established and recently developed frequency synthesizer design techniques. Professionals find expert guidance on all design aspects, including main architectures, key building blocks, and practical circuit implementation. Engineers learn the development process and gain a solid understanding

  7. High carrier frequency of 21-hydroxylase deficiency in Cyprus.

    Science.gov (United States)

    Phedonos, A A P; Shammas, C; Skordis, N; Kyriakides, T C; Neocleous, V; Phylactou, L A

    2013-12-01

    Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is a common autosomal recessive disorder caused by mutations in the CYP21A2 gene. The carrier frequency of CYP21A2 mutations has been estimated to be 1:25 to 1:10 on the basis of newborn screening. The main objective of this study was to determine the carrier frequency in the Cypriot population of mutations in the CYP21A2 gene. Three hundred unrelated subjects (150 males and 150 females) from the general population of Cyprus were screened for mutations in the CYP21A2 gene and its promoter. The CYP21A2 genotype analysis identified six different mutants and revealed a carrier frequency of 9.83% with the mild p.Val281Leu being the most frequent (4.3%), followed by p.Qln318stop (2.5%), p.Pro453Ser (1.33%), p.Val304Met (0.83%), p.Pro482Ser (0.67%) and p.Met283Val (0.17%). The notable high CYP21A2 carrier frequency of the Cypriot population is one of the highest reported so far by genotype analysis. Knowledge of the mutational spectrum of CYP21A2 will enable to optimize mutation detection strategy for genetic diagnosis of 21-OHD not only in Cyprus, but also the greater Mediterranean region.

  8. High-frequency seafloor acoustics

    National Research Council Canada - National Science Library

    Jackson, D. R; Richardson, M. D

    2007-01-01

    This title provides access to experimental data, theory, and models relevant to high-frequency seafloor acoustics and will be of interest to sonar engineers and researchers working in underwater acoustics...

  9. Frequency Steered Acoustic Transducer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase II project is to fabricate, characterize, and verify performance of a new type of frequency steered acoustic transducer...

  10. Harvesting Low-Frequency (Nanogenerator.

    Science.gov (United States)

    Zi, Yunlong; Guo, Hengyu; Wen, Zhen; Yeh, Min-Hsin; Hu, Chenguo; Wang, Zhong Lin

    2016-04-26

    Electromagnetic generators (EMGs) and triboelectric nanogenerators (TENGs) are the two most powerful approaches for harvesting ambient mechanical energy, but the effectiveness of each depends on the triggering frequency. Here, after systematically comparing the performances of EMGs and TENGs under low-frequency motion (10-100 V) and independent of frequency so that most of the generated power can be effectively used to power the devices. Furthermore, a TENG also has advantages of light weight, low cost, and easy scale up through advanced structure designs. All these merits verify the possible killer application of a TENG for harvesting energy at low frequency from motions such as human motions for powering small electronics and possibly ocean waves for large-scale blue energy.

  11. Optical frequency combs generated mechanically

    CERN Document Server

    Sumetsky, M

    2016-01-01

    It is shown that a highly equidistant optical frequency comb can be generated by the parametric excitation of an optical bottle microresonator with nanoscale effective radius variation by its natural mechanical vibrations.

  12. Frequency Steered Acoustic Transducer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project is to develop, fabricate, and characterize a novel frequency steered acoustic transducer (FSAT) for the...

  13. Geographies of High Frequency Trading

    DEFF Research Database (Denmark)

    Grindsted, Thomas Skou

    2016-01-01

    This paper investigates the geographies of high frequency trading. Today shares shift hands within micro seconds, giving rise to a form of financial geographies termed algorithmic capitalism. This notion refers to the different spatio-temporalities produced by high frequency trading, under...... the valuation of time. As high frequency trading accelerates financial markets, the paper examines the spatio-temporalities of automated trading by the ways in which the speed of knowledge exploitation in financial markets is not only of interest, but also the expansion between different temporalities....... The paper demonstrates how the intensification of time-space compression produces radical new dynamics in the financial market and develops information rent in HFT as convertible to a time rent and a spatio-temporal rent. The final section discusses whether high frequency trading only responds to crises...

  14. Parametric effects of word frequency effect in memory for mixed frequency lists

    OpenAIRE

    Lohnas, Lynn J.; Kahana, Michael J.

    2013-01-01

    The word frequency paradox refers to the finding that low frequency words are better recognized than high frequency words yet high frequency words are better recalled than low frequency words. Rather than comparing separate groups of low and high frequency words, we sought to quantify the functional relation between word frequency and memory performance across the broad range of frequencies typically used in episodic memory experiments. Here we report that both low frequency and high frequenc...

  15. The spontaneous chlorophyll mutation frequency in barley

    DEFF Research Database (Denmark)

    Jørgensen, Jørgen Helms; Jensen, Hans Peter

    1986-01-01

    A total of 1866 barley plants were progeny tested in the greenhouse. Twenty-five plants segregated for newly arisen, spontaneous chlorophyll mutant genes. Among the total of 470,129 seedlings screened there were 79 mutants (1.7 .+-. 0.6 .times. 10-4). The data are added to data from three similar...... materials and the resulting estimate of the chlorophyll mutant frequency is 1.6 .times. 10-4 in about 1.43 million seedlings. The estimate of the chlorophyll mutation rate per generation is close to 67.3 .times. 10-4 per diploid genome or in the order of 6 .times. 10-7 per locus and haploid genome....

  16. Primary Frequency Standards at NIST

    Science.gov (United States)

    2001-11-01

    Mode-Locked Laser, ” Physical Review Letters , 82,3568-337 I. J. Reicher, M. Niering, R. Holzwarth, M. Weitz, T. Udem, and T. W. Hansch, 2000, “Phase...Coherent Vacuum- Ultraviolet to Radio Frequency Comparison with a Mode-Locked Laser, ’’ Physical Review Letters , 84,3232-3235. M. Niering, R...Measurement of the Hydrogen IS- 2s Transition Frequency by Phase Coherent Comparison with a Microwave Cesium Fountain Clock,” Physical Review Letters , 84

  17. Microresonator Frequency Comb Optical Clock

    Science.gov (United States)

    2014-07-22

    Number Microresonator frequency comb optical clock Block 13: Supplementary Note © 2014 . Published in Optica , Vol. Ed. 0 1, (1) (2014), (, (1). DoD...Oscillators. http://dx.doi.org/10.1364/ OPTICA .1.000010 1. INTRODUCTION Optical frequency combs enable extraordinary measurement precision and accuracy...1, No. 1 / July 2014 / Optica 10 deviation for 1 s averaging is completely dominated by the Rb reference, and the microcomb contribution is only ɚ

  18. The Dynamic Frequency Assignment Problem

    OpenAIRE

    Dupont, Audrey; Linhares, Andréa,; Artigues, Christian; Feillet, Dominique; Michelon, Philippe; Vasquez, Michel

    2008-01-01

    21 pages; International audience; In this paper, we consider a frequency assignment problem occurring in a military context. The main originality of the problem pertains to its dynamic dimension: new communications requiring frequency assignments need to be established throughout a deployment. The problem decomposes in three phases: assignment of an initial kernel of communications, dynamic assignment of new communication links and reparation when no assignment is possible. Different solution...

  19. Trichoderma genes

    Science.gov (United States)

    Foreman, Pamela [Los Altos, CA; Goedegebuur, Frits [Vlaardingen, NL; Van Solingen, Pieter [Naaldwijk, NL; Ward, Michael [San Francisco, CA

    2012-06-19

    Described herein are novel gene sequences isolated from Trichoderma reesei. Two genes encoding proteins comprising a cellulose binding domain, one encoding an arabionfuranosidase and one encoding an acetylxylanesterase are described. The sequences, CIP1 and CIP2, contain a cellulose binding domain. These proteins are especially useful in the textile and detergent industry and in pulp and paper industry.

  20. Frequency selectivity for frequencies below 100 Hz: comparisons with mid-frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Moore, Brian C.J.

    2010-01-01

    Auditory filter shapes were derived for signal frequencies (fs) between 50 and 1000 Hz, using the notched-noise method. The masker spectrum level (N0) was 50 dB (re 20 μPa). For fs = 63 and 50 Hz, measurements were also made with N0 = 62 dB for the lower band. The data were fitted using a rounded...... of the helicotrema for frequencies below 50 Hz, increasingly influenced the low-frequency skirt of the filters as fs decreased; (6) Detection efficiency worsened with decreasing fs for fs between 100 and 500 Hz, but improved slightly below that....

  1. Latitudinal clines in Drosophila melanogaster: body size, allozyme frequencies, inversion frequencies, and the insulin-signalling pathway

    Indian Academy of Sciences (India)

    Gerdien De Jong; Zoltán Bochdanovits

    2003-12-01

    Many latitudinal clines exist in Drosophila melanogaster: in adult body size, in allele frequency at allozyme loci, and in frequencies of common cosmopolitan inversions. The question is raised whether these latitudinal clines are causally related. This review aims to connect data from two very different fields of study, evolutionary biology and cell biology, in explaining such natural genetic variation in D. melanogaster body size and development time. It is argued that adult body size clines, inversion frequency clines, and clines in allele frequency at loci involved in glycolysis and glycogen storage are part of the same adaptive strategy. Selection pressure is expected to differ at opposite ends of the clines. At high latitudes, selection on D. melanogaster would favour high larval growth rate at low temperatures, and resource storage in adults to survive winter. At low latitudes selection would favour lower larval critical size to survive crowding, and increased male activity leading to high male reproductive success. Studies of the insulin-signalling pathway in D. melanogaster point to the involvement of this pathway in metabolism and adult body size. The genes involved in the insulin-signalling pathway are associated with common cosmopolitan inversions that show latitudinal clines. Each chromosome region connected with a large common cosmopolitan inversion possesses a gene of the insulin transmembrane complex, a gene of the intermediate pathway and a gene of the TOR branch. The hypothesis is presented that temperate D. melanogaster populations have a higher frequency of a ‘thrifty’ genotype corresponding to high insulin level or high signal level, while tropical populations possess a more ‘spendthrift’ genotype corresponding to low insulin or low signal level.

  2. PRRT2 gene mutations

    Science.gov (United States)

    Gardiner, Alice R.; Bhatia, Kailash P.; Stamelou, Maria; Dale, Russell C.; Kurian, Manju A.; Schneider, Susanne A.; Wali, G.M.; Counihan, Tim; Schapira, Anthony H.; Spacey, Sian D.; Valente, Enza-Maria; Silveira-Moriyama, Laura; Teive, Hélio A.G.; Raskin, Salmo; Sander, Josemir W.; Lees, Andrew; Warner, Tom; Kullmann, Dimitri M.; Wood, Nicholas W.; Hanna, Michael

    2012-01-01

    ABSTRACT Objective: The proline-rich transmembrane protein (PRRT2) gene was recently identified using exome sequencing as the cause of autosomal dominant paroxysmal kinesigenic dyskinesia (PKD) with or without infantile convulsions (IC) (PKD/IC syndrome). Episodic neurologic disorders, such as epilepsy, migraine, and paroxysmal movement disorders, often coexist and are thought to have a shared channel-related etiology. To investigate further the frequency, spectrum, and phenotype of PRRT2 mutations, we analyzed this gene in 3 large series of episodic neurologic disorders with PKD/IC, episodic ataxia (EA), and hemiplegic migraine (HM). Methods: The PRRT2 gene was sequenced in 58 family probands/sporadic individuals with PKD/IC, 182 with EA, 128 with HM, and 475 UK and 96 Asian controls. Results: PRRT2 genetic mutations were identified in 28 out of 58 individuals with PKD/IC (48%), 1/182 individuals with EA, and 1/128 individuals with HM. A number of loss-of-function and coding missense mutations were identified; the most common mutation found was the p.R217Pfs*8 insertion. Males were more frequently affected than females (ratio 52:32). There was a high proportion of PRRT2 mutations found in families and sporadic cases with PKD associated with migraine or HM (10 out of 28). One family had EA with HM and another large family had typical HM alone. Conclusions: This work expands the phenotype of mutations in the PRRT2 gene to include the frequent occurrence of migraine and HM with PKD/IC, and the association of mutations with EA and HM and with familial HM alone. We have also extended the PRRT2 mutation type and frequency in PKD and other episodic neurologic disorders. PMID:23077024

  3. Polyploidization increases meiotic recombination frequency in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Rehmsmeier Marc

    2011-04-01

    Full Text Available Abstract Background Polyploidization is the multiplication of the whole chromosome complement and has occurred frequently in vascular plants. Maintenance of stable polyploid state over generations requires special mechanisms to control pairing and distribution of more than two homologous chromosomes during meiosis. Since a minimal number of crossover events is essential for correct chromosome segregation, we investigated whether polyploidy has an influence on the frequency of meiotic recombination. Results Using two genetically linked transgenes providing seed-specific fluorescence, we compared a high number of progeny from diploid and tetraploid Arabidopsis plants. We show that rates of meiotic recombination in reciprocal crosses of genetically identical diploid and autotetraploid Arabidopsis plants were significantly higher in tetraploids compared to diploids. Although male and female gametogenesis differ substantially in meiotic recombination frequency, both rates were equally increased in tetraploids. To investigate whether multivalent formation in autotetraploids was responsible for the increased recombination rates, we also performed corresponding experiments with allotetraploid plants showing strict bivalent pairing. We found similarly increased rates in auto- and allotetraploids, suggesting that the ploidy effect is independent of chromosome pairing configurations. Conclusions The evolutionary success of polyploid plants in nature and under domestication has been attributed to buffering of mutations and sub- and neo-functionalization of duplicated genes. Should the data described here be representative for polyploid plants, enhanced meiotic recombination, and the resulting rapid creation of genetic diversity, could have also contributed to their prevalence.

  4. Polymorphism Trp64Arg of beta 3 adrenoreceptor gene: allelic frequencies and influence on insulin resistance in a multicenter study of Castilla-León Polimorfismo TRP64ARG del gen receptor beta 3: frecuencia alélica e influencia en la resistencia a la insulina en un estudio multicéntrico de Castilla y León

    Directory of Open Access Journals (Sweden)

    D. A. de Luis

    2010-04-01

    Full Text Available Background and objective: The genetic variant (Trp64Arg is a missense mutation located within the beta3 adrenoreceptor (Beta3AR. The aim of our study was to investigate the influence of Trp64Arg polymorphism in the Beta3AR gene on insulin resistance in obese patients and the allelic distribution of this polymorphismin a geographic area of Spain. Design: A population of 264 obese patients was analyzed. A bioimpedance, blood pressure, an assessment of nutritional intake, and biochemical parameters were measured. The beta 3 adrenoreceptor gene polymorphism(Trp64Arg was genotyped. Results: Two hundred and twenty six patients (77 males/149 females (85.6% had the genotype Trp64/Trp64 (wild type group with and average age of 41.12 ± 13.1 years and 38 patients (16 males/22 females Trp64/Arg64 (14.4% (mutant type group with an average age of 40.5 ± 12.7 years. High frequencies of Arg64 allele were observed in Salamanca and Valladolid. In the mutant type group, HOMA (3.75 ± 2.77 vs 5.27 ± 5.4; p Introducción y objetivos: La variante genética (Trp64Arg es una mutación localizada en el adrenoreceptor Beta 3 (Beta3AR. El objetivo de nuestro trabajo es evaluar la influencia de el polimorfismo Trp64Arg del gen de Beta3AR sobre la resistencia a la insulina en pacientes obesos, así como la distribución alélica de este polimorfismo en un área geográfica de España. Diseño: Una muestra de 264 pacientes obesos fue analizada. Se realizó una bioimpedancia, evaluación nutricional y análisis bioquímico. Se genotiparon a los pacientes en función delpolimorfismos Tr64Arg del gen adrenoreceptor-beta 3. Resultados: Un total de 227 pacientes (77 varones/149 mujeres (85,6% presentaron el genotipo Trp64/Trp64 (grupo genotipo salvaje, con una media de edad de 41,12 ± 13,1 años y un total de 38 pacientes (16 varones/22 mujeres Trp64/Arg64 (14,4% (grupo genotipo mutante con una edad media de 40,5 ± 12,7 años. Se detectó una alta frecuencia alélica (Arg64

  5. Components of cross-frequency modulation in health and disease

    Directory of Open Access Journals (Sweden)

    Elena A Allen

    2011-07-01

    Full Text Available The cognitive deficits associated with schizophrenia are commonly believed to arise from the abnormal temporal integration of information, however a quantitative approach to assess network coordination is lacking. Here, we propose to use cross-frequency modulation, the dependence of local high-frequency activity on the phase of widespread low-frequency oscillations, as an indicator of network coordination and functional integration. In an exploratory analysis based on pre-existing data, we measured cross-frequency modulation from multi-channel EEG recordings acquired while schizophrenia patients (n = 47 and healthy controls (n = 130 performed an auditory oddball task. Novel application of independent component analysis (ICA to modulation data delineated components with specific spatial and spectral profiles, the weights of which showed co-variation with diagnosis. Global cross-frequency modulation was significantly greater in healthy controls (F1,175=9.25, P<0.005, while modulation at fronto-temporal electrodes was greater in patients (F1,175 =17.5, P<0.0001. We further found that the weights of schizophrenia-relevant components were associated with genetic polymorphisms at previously identified risk loci. Global cross-frequency modulation decreased with copies of 957C allele in the gene for the dopamine D2 receptor (r = −0.20, P < 0.01 across all subjects. Additionally, greater ‘aberrant’ fronto-temporal modulation in schizophrenia patients was correlated with several polymorphisms in the gene for the α2-subunit of the GABAA receptor (GABRA2 as well as the total number of risk alleles in GABRA2 (r = 0.45, P < 0.01. Overall, our results indicate great promise for this approach in establishing patterns of cross-frequency modulation in health and disease and elucidating the roles of oscillatory interactions in functional connectivity.

  6. Medea genes, handedness and other traits

    Science.gov (United States)

    Hatfield, Jeffrey

    2015-01-01

    Medea factors or genes are maternal-effects mechanisms, found in many species, in which the mother's body selectively kills embryos of a certain genotype.Humans have a similar genetic mechanism, the gene RHD which produces Rh-factor involved in blood type.Recently I proposed that RHD acts as a maternal-effects gene that determines handedness (i.e., right handed or non-right handed) in individuals of our species. Here, I argue that RHD functions as a Medea gene as well.The handedness gene (and also RHD itself in some cases) has been implicated in autism spectrum disorders (ASD), bipolar disorder, cerebral laterality (i.e., right-brained or left-brained speech laterality), hair-whorl rotation, schizophrenia, sexual orientation, and speech dyslexia.Identifying the gene or genes that determine handedness or cerebral laterality may help uncover the mechanisms underlying these behavioral phenotypes in our species.A relatively simple test of the handedness hypothesis has been proposed:In a sample of humans for whom handedness has been evaluated, we would need to genotype for RHD by determining whether Rh+ individuals have one or two copies of the dominant allele. If RHD and perhaps also an interaction with RHCE are involved in sexual orientation, it explains how selection could favor a gene or genes which cause some people to become non-heterosexual.The literature on Medea genes provides the explanation:A Medea allele must increase in frequency, sometimes to fixation (i.e., 100% frequency) even if it reduces fecundity (e.g., birth rate).In addition, treatment for RHD maternal-fetal genotype incompatibility, which allows more fetuses to survive to term now, may be one explanation for why ASD appears to be increasing in frequency in some populations, if RHD is indeed the handedness gene, although many other mechanisms have also been suggested. One wonders if bipolar disorder and the other alternative phenotypes are also increasing in frequency.

  7. Demand as frequency controlled reserve

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Togeby, M.; OEstergaard, J.

    2008-09-15

    Using demand as frequency controlled reserve (DFR) is an emerging technology which allow demand to participate actively in maintaining the system operation without reducing the energy service delivered to the customer and without need of user interaction. The basic premise is that traditional frequency controlled reserves from power plants and interconnections with neighbouring systems can be costly, slow and not fulfil the need for future power grids with a high share of wind power and fewer central power plants, and an intention to perform flexible operation such as is landing. Electricity demands, on the other hand, have advantages as frequency reserve including fast activation speed, smooth linear activation, low expected costs, and well-dispersed in the distribution grid. The main challenge of DFR is new methods for monitoring the available capacity. This project has investigated the technology of using electricity demands for providing frequency reserve to power systems. Within the project the potential and economy of DFR compatible loads in Denmark has been investigated, control logic has been designed, power system impact has been investigated, potential business models has been evaluated and an implementation strategy has been suggested. The tasks and goals of the project have been successfully accomplished based on which the conclusion and future recommendation are made. This project has developed the DFR technology that enables electricity demands to autonomously disconnect or reconnect to the grid in response to system frequency variations. The developed DFR technology is proved to be a promising technology from several perspectives. Technically, using DFR is feasible to provide reserves and enhance power system frequency control, while fulfilling technical requirements such as linear activation (or reconnection) according to frequency (or time). Environmentally, the DFR technology is pollution free in contrast to traditional reserves from generation

  8. Study on gene sensor based on primer extension

    Institute of Scientific and Technical Information of China (English)

    陈誉华; 宋今丹; 李大为

    1997-01-01

    Based on the fact that the resonant frequency of a piezoelectric crystal is the function of its surface deposit, and that the primer extends after it hybridizes with the template, the primer extension gene sensor technique was developed. The prominent feature of the technique is that fast and sensitive frequency signals are used as the monitoring system of gene hybridization and primer strand extension. Results show that this technique may be used in homologous analysis of nucleic acid, trace DNA detection, and determining the integration of DNA. It may also be used for isolation of target gene, gene mutation analysis, and predicting the location of a gene in its genome.

  9. Robust identification of local adaptation from allele frequencies.

    Science.gov (United States)

    Günther, Torsten; Coop, Graham

    2013-09-01

    Comparing allele frequencies among populations that differ in environment has long been a tool for detecting loci involved in local adaptation. However, such analyses are complicated by an imperfect knowledge of population allele frequencies and neutral correlations of allele frequencies among populations due to shared population history and gene flow. Here we develop a set of methods to robustly test for unusual allele frequency patterns and correlations between environmental variables and allele frequencies while accounting for these complications based on a Bayesian model previously implemented in the software Bayenv. Using this model, we calculate a set of "standardized allele frequencies" that allows investigators to apply tests of their choice to multiple populations while accounting for sampling and covariance due to population history. We illustrate this first by showing that these standardized frequencies can be used to detect nonparametric correlations with environmental variables; these correlations are also less prone to spurious results due to outlier populations. We then demonstrate how these standardized allele frequencies can be used to construct a test to detect SNPs that deviate strongly from neutral population structure. This test is conceptually related to FST and is shown to be more powerful, as we account for population history. We also extend the model to next-generation sequencing of population pools-a cost-efficient way to estimate population allele frequencies, but one that introduces an additional level of sampling noise. The utility of these methods is demonstrated in simulations and by reanalyzing human SNP data from the Human Genome Diversity Panel populations and pooled next-generation sequencing data from Atlantic herring. An implementation of our method is available from http://gcbias.org.

  10. Ecological genetics of the Bromus tectorum (Poaceae) - Ustilago Bullata (Ustilaginaceae): A role for frequency dependent selection?

    Science.gov (United States)

    Susan E. Meyer; David L. Nelson; Suzette Clement; Alisa Ramakrishnan

    2010-01-01

    Evolutionary processes that maintain genetic diversity in plants are likely to include selection imposed by pathogens. Negative frequency-dependent selection is a mechanism for maintenance of resistance polymorphism in plant - pathogen interactions. We explored whether such selection operates in the Bromus tectorum - Ustilago bullata pathosystem. Gene-for-gene...

  11. C282Y and H63D Mutation Frequencies in a Population from Central Spain

    Directory of Open Access Journals (Sweden)

    S. Alvarez

    2001-01-01

    Full Text Available Objectives: To determine the frequency of hereditary hemochromatosis gene mutations, C282Y and H63D, from 125 autochthonous blood donors originating from a Central region of Spain, to provide epidemiological data about HFE gene in the Iberian Peninsula.

  12. Charcot-Marie-Tooth disease: frequency of genetic subtypes and guidelines for genetic testing.

    LENUS (Irish Health Repository)

    Murphy, Sinead M

    2012-07-01

    Charcot-Marie-Tooth disease (CMT) is a clinically and genetically heterogeneous group of diseases with approximately 45 different causative genes described. The aims of this study were to determine the frequency of different genes in a large cohort of patients with CMT and devise guidelines for genetic testing in practice.

  13. [Promotion of transformation frequency of soybean (Glycine max L.) protoplasts using poly-L-ornithine].

    Science.gov (United States)

    Nan, X R; Wei, Z M

    1999-12-01

    The foreign Bt gene was transferred into protoplasts of soybean using PEG and PLO methods, respectively. The result indicated that the transformation frequency of PLO method was about 0.1% higher than PEG method. The PCR and Southern blotting analysis of the regeneration plants confirmed the integration of foreign gene into the genome of soybean.

  14. Gene Therapy.

    Science.gov (United States)

    Thorne, Barb; Takeya, Ryan; Vitelli, Francesca; Swanson, Xin

    2017-03-14

    Gene therapy refers to a rapidly growing field of medicine in which genes are introduced into the body to treat or prevent diseases. Although a variety of methods can be used to deliver the genetic materials into the target cells and tissues, modified viral vectors represent one of the more common delivery routes because of its transduction efficiency for therapeutic genes. Since the introduction of gene therapy concept in the 1970s, the field has advanced considerably with notable clinical successes being demonstrated in many clinical indications in which no standard treatment options are currently available. It is anticipated that the clinical success the field observed in recent years can drive requirements for more scalable, robust, cost effective, and regulatory-compliant manufacturing processes. This review provides a brief overview of the current manufacturing technologies for viral vectors production, drawing attention to the common upstream and downstream production process platform that is applicable across various classes of viral vectors and their unique manufacturing challenges as compared to other biologics. In addition, a case study of an industry-scale cGMP production of an AAV-based gene therapy product performed at 2,000 L-scale is presented. The experience and lessons learned from this largest viral gene therapy vector production run conducted to date as discussed and highlighted in this review should contribute to future development of commercial viable scalable processes for vial gene therapies.

  15. Parametric Effects of Word Frequency in Memory for Mixed Frequency Lists

    Science.gov (United States)

    Lohnas, Lynn J.; Kahana, Michael J.

    2013-01-01

    The "word frequency paradox" refers to the finding that low frequency words are better recognized than high frequency words yet high frequency words are better recalled than low frequency words. Rather than comparing separate groups of low and high frequency words, we sought to quantify the functional relation between word frequency and…

  16. Quantum Cascade Laser Frequency Combs

    CERN Document Server

    Faist, Jérôme; Scalari, Giacomo; Rösch, Markus; Bonzon, Christopher; Hugi, Andreas; Beck, Mattias

    2015-01-01

    It was recently demonstrated that broadband quantum cascade lasers can operate as frequency combs. As such, they operate under direct electrical pumping at both mid-infrared and THz frequencies, making them very attractive for dual-comb spectroscopy. Performance levels are continuously improving, with average powers over 100 mW and frequency coverage of 100 cm$^{-1}$ in the mid-infrared. In the THz range, 10 mW of average power and 600 GHz of frequency coverage are reported. As a result of the very short upper state lifetime of the gain medium, the mode proliferation in these sources arises from four wave mixing rather than saturable absorption. As a result, their optical output is characterized by the tendency of small intensity modulation of the output power, and the relative phases of the modes to be similar to the ones of a frequency modulated laser. Recent results include the proof of comb operation down to a metrological level, the observation of a Schawlow-Townes broadened linewidth, as well as the fir...

  17. Quantum Cascade Laser Frequency Combs

    Directory of Open Access Journals (Sweden)

    Faist Jérôme

    2016-06-01

    Full Text Available It was recently demonstrated that broadband quantum cascade lasers can operate as frequency combs. As such, they operate under direct electrical pumping at both mid-infrared and THz frequencies, making them very attractive for dual-comb spectroscopy. Performance levels are continuously improving, with average powers over 100mW and frequency coverage of 100 cm-1 in the mid-infrared region. In the THz range, 10mW of average power and 600 GHz of frequency coverage are reported. As a result of the very short upper state lifetime of the gain medium, the mode proliferation in these sources arises from four-wave mixing rather than saturable absorption. As a result, their optical output is characterized by the tendency of small intensity modulation of the output power, and the relative phases of the modes to be similar to the ones of a frequency modulated laser. Recent results include the proof of comb operation down to a metrological level, the observation of a Schawlow-Townes broadened linewidth, as well as the first dual-comb spectroscopy measurements. The capability of the structure to integrate monothically nonlinear optical elements as well as to operate as a detector shows great promise for future chip integration of dual-comb systems.

  18. Active Faraday optical frequency standard.

    Science.gov (United States)

    Zhuang, Wei; Chen, Jingbiao

    2014-11-01

    We propose the mechanism of an active Faraday optical clock, and experimentally demonstrate an active Faraday optical frequency standard based on narrow bandwidth Faraday atomic filter by the method of velocity-selective optical pumping of cesium vapor. The center frequency of the active Faraday optical frequency standard is determined by the cesium 6 (2)S(1/2) F=4 to 6 (2)P(3/2) F'=4 and 5 crossover transition line. The optical heterodyne beat between two similar independent setups shows that the frequency linewidth reaches 281(23) Hz, which is 1.9×10(4) times smaller than the natural linewidth of the cesium 852-nm transition line. The maximum emitted light power reaches 75 μW. The active Faraday optical frequency standard reported here has advantages of narrow linewidth and reduced cavity pulling, which can readily be extended to other atomic transition lines of alkali and alkaline-earth metal atoms trapped in optical lattices at magic wavelengths, making it useful for new generation of optical atomic clocks.

  19. Association studies of low-frequency coding variants in nonsyndromic cleft lip with or without cleft palate

    DEFF Research Database (Denmark)

    Leslie, Elizabeth J; Carlson, Jenna C; Shaffer, John R

    2017-01-01

    Test (SKAT) and Combined Multivariate and Collapsing (CMC) method using two minor allele frequency cutoffs (1% and 5%). We found that a burden of low-frequency coding variants in N4BP2, CDSN, PRTG, and AHRR were associated with increased risk of NSCL/P. Low-frequency variants in other genes were...... associated with decreased risk of NSCL/P. These results demonstrate that low-frequency variants contribute to the genetic etiology of NSCL/P....

  20. 47 CFR 80.1077 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 80.1077 Section 80.1077... Frequencies. The following table describes the frequencies used in the Global Maritime Distress and Safety... frequency 9 GHz radar transponders 9200-9500 MHz. 1 Frequency 156.525 MHz can be used for...

  1. 47 CFR 74.464 - Frequency tolerance.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Frequency tolerance. 74.464 Section 74.464....464 Frequency tolerance. For operations on frequencies above 25 MHz using authorized bandwidths up to... frequency of each station in compliance with the frequency tolerance requirements of § 90.213 of...

  2. 47 CFR 78.111 - Frequency tolerance.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Frequency tolerance. 78.111 Section 78.111... SERVICE Technical Regulations § 78.111 Frequency tolerance. Stations in this service shall maintain the... frequency. Frequency band (MHz) Frequency tolerance Fixed (percent) Mobile (percent) 1,990 to 2,110 0.005...

  3. Partnership concurrency and coital frequency.

    Science.gov (United States)

    Gaydosh, Lauren; Reniers, Georges; Helleringer, Stéphane

    2013-09-01

    National HIV prevalence estimates across sub-Saharan Africa range from less than 1 percent to over 25 percent. Recent research proposes several explanations for the observed variation, including prevalence of male circumcision, levels of condom use, presence of other sexually transmitted infections, and practice of multiple concurrent partnerships. However, the importance of partnership concurrency for HIV transmission may depend on how it affects coital frequency with each partner. The coital dilution hypothesis suggests that coital frequency within a partnership declines with the addition of concurrent partners. Using sexual behavior data from rural Malawi and urban Kenya, we investigate the relationship between partnership concurrency and coital frequency, and find partial support for the coital dilution hypothesis. We conclude the paper with a discussion of our findings in light of the current literature on concurrency.

  4. High-frequency Trader Subjectivity

    DEFF Research Database (Denmark)

    Borch, Christian; Lange, Ann-Christina

    2017-01-01

    In this article, we examine the recent shift in financial markets toward high-frequency trading (HFT). This turn is being legitimized with reference to how algorithms are allegedly more rational and efficient than human traders, and less prone to emotionally motivated decisions. We argue...... that although HFT does not render humans irrelevant, it is leading to a reconfiguration of both the ideal trading subject and the human–machine relations. Drawing on interviews with and ethnographic observations of high-frequency traders, as well as HFT ‘how to’ books, we analyze the subjectivity and self......-techniques of the ideal high-frequency trader. We demonstrate that these traders face the challenge of avoiding emotional interference in their algorithms and that they deploy a set of disciplinary self-techniques to curb the importance of emotional attachment....

  5. The instantaneous frequency rate spectrogram

    Science.gov (United States)

    Czarnecki, Krzysztof

    2016-01-01

    An accelerogram of the instantaneous phase of signal components referred to as an instantaneous frequency rate spectrogram (IFRS) is presented as a joint time-frequency distribution. The distribution is directly obtained by processing the short-time Fourier transform (STFT) locally. A novel approach to amplitude demodulation based upon the reassignment method is introduced as a useful by-product. Additionally, an estimator of energy density versus the instantaneous frequency rate (IFR) is proposed and referred to as the IFR profile. The energy density is estimated based upon both the classical energy spectrogram and the IFRS smoothened by the median filter. Moreover, the impact of an analyzing window width, additive white Gaussian noise and observation time is tested. Finally, the introduced method is used for the analysis of the acoustic emission of an automotive engine. The recording of the engine of a Lamborghini Gallardo is analyzed as an example.

  6. Swept Frequency Laser Metrology System

    Science.gov (United States)

    Zhao, Feng (Inventor)

    2010-01-01

    A swept frequency laser ranging system having sub-micron accuracy that employs multiple common-path heterodyne interferometers, one coupled to a calibrated delay-line for use as an absolute reference for the ranging system. An exemplary embodiment uses two laser heterodyne interferometers to create two laser beams at two different frequencies to measure distance and motions of target(s). Heterodyne fringes generated from reflections off a reference fiducial X(sub R) and measurement (or target) fiducial X(sub M) are reflected back and are then detected by photodiodes. The measured phase changes Delta phi(sub R) and Delta phi (sub m) resulting from the laser frequency swept gives target position. The reference delay-line is the only absolute reference needed in the metrology system and this provides an ultra-stable reference and simple/economical system.

  7. Gene Therapy

    Science.gov (United States)

    ... or improve your body's ability to fight disease. Gene therapy holds promise for treating a wide range of diseases, such as cancer, cystic fibrosis, heart disease, diabetes, hemophilia and AIDS. Researchers are still studying how and ...

  8. Surface Acoustic Wave Frequency Comb

    CERN Document Server

    Savchenkov, A A; Ilchenko, V S; Seidel, D; Maleki, L

    2011-01-01

    We report on realization of an efficient triply-resonant coupling between two long lived optical modes and a high frequency surface acoustic wave (SAW) mode of the same monolithic crystalline whispering gallery mode resonator. The coupling results in an opto-mechanical oscillation and generation of a monochromatic SAW. A strong nonlinear interaction of this mechanical mode with other equidistant SAW modes leads to mechanical hyper-parametric oscillation and generation of a SAW pulse train and associated frequency comb in the resonator. We visualized the comb observing the modulation of the modulated light escaping the resonator.

  9. DOA estimation exploiting coprime frequencies

    Science.gov (United States)

    Qin, Si; Zhang, Yimin D.; Amin, Moeness G.

    2014-05-01

    Coprime array, which utilizes a coprime pair of uniform linear subarrays, is an attractive structure to achieve sparse array configurations. Alternatively, effective coprime array configurations can be implemented using a uniform linear array with two coprime sensing frequencies. This enables the integration of the coprime array and filter concepts to achieve high capabilities in meeting system performance and complexity constraints. This paper examines its performance for direction-of-arrival estimations. In particular, we analyze the number of detectable signals and the estimation accuracy as related to the array configurations and sensing frequencies.

  10. High-frequency complex pitch

    DEFF Research Database (Denmark)

    Santurette, Sébastien; Dau, Torsten

    2012-01-01

    Harmonics in a complex tone are typically considered unresolved when they interact with neighboring harmonics in the cochlea and cannot be heard out separately. Recent studies have suggested that the low pitch evoked by unresolved high-frequency harmonics may be coded via temporal fine-structure ......Harmonics in a complex tone are typically considered unresolved when they interact with neighboring harmonics in the cochlea and cannot be heard out separately. Recent studies have suggested that the low pitch evoked by unresolved high-frequency harmonics may be coded via temporal fine...

  11. Frequency of self-oscillations

    CERN Document Server

    Groszkowski, Janusz

    2013-01-01

    Frequency of Self-Oscillations covers the realm of electric oscillations that plays an important role both in the scientific and technical aspects. This book is composed of nine chapters, and begins with the introduction to the alternating currents and oscillation. The succeeding chapters deal with the free oscillations in linear isolated systems. These topics are followed by discussions on self-oscillations in linear systems. Other chapters describe the self-oscillations in non-linear systems, the influence of linear elements on frequency of oscillations, and the electro mechanical oscillato

  12. Genes V.

    Energy Technology Data Exchange (ETDEWEB)

    Lewin, B.

    1994-12-31

    This fifth edition book encompasses a wide range of topics covering 1,272 pages. The book is arranged into nine parts with a total of 36 chapters. These nine parts include Introduction; DNA as a Store of Information; Translation; Constructing Cells; Control of Prokaryotypic Gene Expression; Perpetuation of DNA; Organization of the Eukaryotypic Genome; Eukaryotypic Transcription and RNA Processing; The Dynamic Genome; and Genes in Development.

  13. Control of meiotic recombination frequency in plant genomes.

    Science.gov (United States)

    Henderson, Ian R

    2012-11-01

    Sexual eukaryotes reproduce via the meiotic cell division, where ploidy is halved and homologous chromosomes undergo reciprocal genetic exchange, termed crossover (CO). CO frequency has a profound effect on patterns of genetic variation and species evolution. Relative CO rates vary extensively both within and between plant genomes. Plant genome size varies by over 1000-fold, largely due to differential expansion of repetitive sequences, and increased genome size is associated with reduced CO frequency. Gene versus repeat sequences associate with distinct chromatin modifications, and evidence from plant genomes indicates that this epigenetic information influences CO patterns. This is consistent with data from diverse eukaryotes that demonstrate the importance of chromatin structure for control of meiotic recombination. In this review I will discuss CO frequency patterns in plant genomes and recent advances in understanding recombination distributions.

  14. The Frequency of Some Thrombophilic Mutations in Eastern Turkey.

    Science.gov (United States)

    Ozturk, Nurinnisa; Bakan, Ebubekir; Gul, Mehmet Ali; Bakan, Nuri; Sebin, Engin; Kiziltunc, Ahmet

    2016-02-01

    Factor V / Factor II / Methylenetetrahydrofolate reductase, gene polymorphisms are closely associated with thrombophilia. Regional frequencies of these mutations may show a characteristic state. The aim of our study was to evaluate the frequency of commonly seen Factor V / Factor II / Methylenetetrahydrofolate reductase gene polymorphisms in Eastern Turkey. In 433 patients sent to the laboratory with the suspicion of thrombophilia, using whole blood samples, an automated Nucleic Acid Test was used for mutation determinations in Verigene System. The kit module was designed to detect the Factor V G1691A / Factor II G20210A / Methylenetetrahydrofolate reductase gene C677T single nucleotide polymorphisms. In 433 patients, 8.7% for Factor V G1691A polymorphisms were heterozygous genotype, 3.9% for Factor II G20210A polymorphisms were heterozygous genotype, and 43.9% for methylenetetrahydrofolate reductase 677C>T polymorphisms were heterozygous genotype and 3.0% homozygous mutation genotype. Detection of these commonly seen Factor V / Factor II / Methylenetetrahydrofolate reductase single nucleotide polymorphisms can help to identify patients in high risk group and to evaluate the interaction of genetic and acquired risk factors. Our findings suggest that commonly seen thrombophilic allele mutation frequency in our region is the same as the data reported in the literature.

  15. Low Frequency Radio Experiment (LORE)

    Science.gov (United States)

    Manoharan, P. K.; Naidu, Arun; Joshi, B. C.; Roy, Jayashree; Kate, G.; Pethe, Kaiwalya; Galande, Shridhar; Jamadar, Sachin; Mahajan, S. P.; Patil, R. A.

    2016-03-01

    In this paper, we present a case study of Low Frequency Radio Experiment (LORE) payload to probe the corona and the solar disturbances at solar offsets greater than 2 solar radii, i.e., at frequencies below 30 MHz. The LORE can be complimentary to the planned Indian solar mission, “Aditya-L1” and its other payloads as well as synergistic to ground-based interplanetary scintillation (IPS) observations, which are routinely carried out by the Ooty Radio Telescope. We discuss the baseline design and technical details of the proposed LORE and its particular suitability for providing measurements on the detailed time and frequency structure of fast drifting type-III and slow drifting type-II radio bursts with unprecedented time and frequency resolutions. We also brief the gonio-polarimetry, which is possible with better-designed antennas and state-of-the-art electronics, employing FPGAs and an intelligent data management system. These would enable us to make a wide range of studies, such as nonlinear plasma processes in the Sun-Earth distance, in-situ radio emission from coronal mass ejections (CMEs), interplanetary CME driven shocks, nature of ICMEs driving decelerating IP shocks and space weather effects of solar wind interaction regions.

  16. Radio frequency propagation made easy

    CERN Document Server

    Faruque, Saleh

    2015-01-01

    This book introduces Radio Frequency Propagation to a broad audience.  The author blends theory and practice to bring readers up-to-date in key concepts, underlying principles and practical applications of wireless communications.  The presentation is designed to be easily accessible, minimizing mathematics and maximizing visuals.

  17. Radio Frequency Solid State Amplifiers

    CERN Document Server

    Jacob, J

    2015-01-01

    Solid state amplifiers are being increasingly used instead of electronic vacuum tubes to feed accelerating cavities with radio frequency power in the 100 kW range. Power is obtained from the combination of hundreds of transistor amplifier modules. This paper summarizes a one hour lecture on solid state amplifiers for accelerator applications.

  18. LEP radio-frequency cavity

    CERN Multimedia

    1991-01-01

    One of the copper radio-frequency accelerating cavities installed for the first phase of LEP (1989-1995). Bunches of electrons and positrons circulated in LEP in opposite directions and were accelerated in eight different sets of 16 cavities (situated on either side of the four experiments), gaining 400 million volts of accelerating power per turn.

  19. Frequency-Domain Optical Mammogram

    Science.gov (United States)

    2002-10-01

    the tumor. * Combination of the above two points into a composite false-color breast image containing structural information (from the second...Antonangeli, A. Savoia, T. Parasassi, and N. Rosato, " Plastique : a synchrotron radiation beamline for time resolved fluorescence in the frequency domain

  20. Low-frequency noise complaints

    DEFF Research Database (Denmark)

    Pedersen, Christian Sejer; Møller, Henrik; Persson-Waye, Kerstin

    2006-01-01

    In Denmark and in other industrialized countries there are cases where people complain about annoying low-frequency or infrasonic noise in their homes. Besides noise annoyance people often report other adverse effects such as insomnia, headache, lack of concentration etc. In many cases the noise...

  1. Radio frequency modulation made easy

    CERN Document Server

    Faruque, Saleh

    2017-01-01

    This book introduces Radio Frequency Modulation to a broad audience. The author blends theory and practice to bring readers up-to-date in key concepts, underlying principles and practical applications of wireless communications. The presentation is designed to be easily accessible, minimizing mathematics and maximizing visuals.

  2. Demand as Frequency Controlled Reserve

    DEFF Research Database (Denmark)

    Xu, Zhao; Østergaard, Jacob; Togeby, Mikael

    2011-01-01

    Relying on generation side alone is deemed insufficient to fulfill the system balancing needs for future Danish power system, where a 50% wind penetration is outlined by the government for year 2025. This paper investigates using the electricity demand as frequency controlled reserve (DFR) as a new...

  3. High Resolution Frequency Swept Imaging.

    Science.gov (United States)

    1980-02-14

    centers on practical targets. (iv) Greater immunity to phase fluctuations arising from turbulance and inhomogenieties in the propagation medium because...frequency swept illumination. Since the impulse reponse of a time invariant linear system can also be deduced from white noise excitation and

  4. Spatial frequency domain error budget

    Energy Technology Data Exchange (ETDEWEB)

    Hauschildt, H; Krulewich, D

    1998-08-27

    The aim of this paper is to describe a methodology for designing and characterizing machines used to manufacture or inspect parts with spatial-frequency-based specifications. At Lawrence Livermore National Laboratory, one of our responsibilities is to design or select the appropriate machine tools to produce advanced optical and weapons systems. Recently, many of the component tolerances for these systems have been specified in terms of the spatial frequency content of residual errors on the surface. We typically use an error budget as a sensitivity analysis tool to ensure that the parts manufactured by a machine will meet the specified component tolerances. Error budgets provide the formalism whereby we account for all sources of uncertainty in a process, and sum them to arrive at a net prediction of how "precisely" a manufactured component can meet a target specification. Using the error budget, we are able to minimize risk during initial stages by ensuring that the machine will produce components that meet specifications before the machine is actually built or purchased. However, the current error budgeting procedure provides no formal mechanism for designing machines that can produce parts with spatial-frequency-based specifications. The output from the current error budgeting procedure is a single number estimating the net worst case or RMS error on the work piece. This procedure has limited ability to differentiate between low spatial frequency form errors versus high frequency surface finish errors. Therefore the current error budgeting procedure can lead us to reject a machine that is adequate or accept a machine that is inadequate. This paper will describe a new error budgeting methodology to aid in the design and characterization of machines used to manufacture or inspect parts with spatial-frequency-based specifications. The output from this new procedure is the continuous spatial frequency content of errors that result on a machined part. If the machine

  5. Tagging Blast Resistance Gene Pi 1 in Rice (Oryza sativa) Using Candidate Resistance Genes

    Institute of Scientific and Technical Information of China (English)

    LI Ai-hong; WU Jian-li; XU Xin-ping; Menchu BERNADO; DAI Zheng-yuan; ZHUANG Jie-yun; CHEN Zong-xiang; ZHENG Kang-le; LI Bao-jian; Hei LEUNG; ZHANG Hong-xi; PAN Xue-biao

    2004-01-01

    An F3 population derived from C101LAC/CO39 containing 90 lines was analyzed for blast resistance with 48 candidate genes developed from resistance gene analogs (RGA) and suppression subtractive library. Genetic analysis confirmed that blast resistance of the population was controlled by a single gene Pi 1. One of the candidate genes, R10 was identified as associated with the blast resistance gene on the long arm of chromosome 11 and mapped using a DH population derived from Azucena/IR64.A pair of PCR based primers was designed based on the sequence of R10 for marker-aided selection of the blast resistance gene.The recombination frequency between Pi 1 and the marker was estimated as 1.28%. It suggested that strategy of employing candidate genes is useful for gene identification and mapping. A new RFLP marker and the corresponding PCR marker for tagging of Pi 1 were provided.

  6. 47 CFR 25.202 - Frequencies, frequency tolerance and emission limitations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Frequencies, frequency tolerance and emission... CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.202 Frequencies, frequency tolerance and emission limitations. (a)(1) Frequency band. The following frequencies are available for use...

  7. Frequency discrimination of brief tonal steps as a function of frequency in the lesser bulldog bat.

    Science.gov (United States)

    Roverud, R C

    1999-09-01

    In a two-alternative, forced-choice task lesser bulldog bats were trained to distinguish between a pure tone pulse and a pulse composed of a series of brief tonal steps oscillating between two different frequencies. The tone-step pulse gradually approximates the pure tone pulse as the frequency difference between the steps becomes progressively smaller. Frequency difference limens for the brief tonal frequency steps were determined for a broad range of ultrasonic frequencies. The variation in tone-step difference limens with frequency appears to be correlated to the frequency structure of the bat's short-constant-frequency/frequency-modulated echolocation sound. There was a marked decline in the value of the relative frequency difference limens (Weber ratio) over a fairly narrow range of frequencies above the constant frequency and a sharp increase in threshold above this range. The relative thresholds for frequency discrimination were small and uniform over the frequency range of the frequency-modulated sweep and increased for frequencies below the frequency-modulated sweep. Thus, the most accurate frequency-discrimination abilities occur over a narrow frequency range around the frequency of the constant-frequency component of returning echoes. Frequency discrimination over the range of frequencies of the frequency-modulated component is relatively good.

  8. Amplified and homozygously deleted genes in glioblastoma: impact on gene expression levels.

    Directory of Open Access Journals (Sweden)

    Inês Crespo

    Full Text Available BACKGROUND: Glioblastoma multiforme (GBM displays multiple amplicons and homozygous deletions that involve relevant pathogenic genes and other genes whose role remains unknown. METHODOLOGY: Single-nucleotide polymorphism (SNP-arrays were used to determine the frequency of recurrent amplicons and homozygous deletions in GBM (n = 46, and to evaluate the impact of copy number alterations (CNA on mRNA levels of the genes involved. PRINCIPAL FINDINGS: Recurrent amplicons were detected for chromosomes 7 (50%, 12 (22%, 1 (11%, 4 (9%, 11 (4%, and 17 (4%, whereas homozygous deletions involved chromosomes 9p21 (52% and 10q (22%. Most genes that displayed a high correlation between DNA CNA and mRNA levels were coded in the amplified chromosomes. For some amplicons the impact of DNA CNA on mRNA expression was restricted to a single gene (e.g., EGFR at 7p11.2, while for others it involved multiple genes (e.g., 11 and 5 genes at 12q14.1-q15 and 4q12, respectively. Despite homozygous del(9p21 and del(10q23.31 included multiple genes, association between these DNA CNA and RNA expression was restricted to the MTAP gene. CONCLUSIONS: Overall, our results showed a high frequency of amplicons and homozygous deletions in GBM with variable impact on the expression of the genes involved, and they contributed to the identification of other potentially relevant genes.

  9. Natural frequency of regular basins

    Science.gov (United States)

    Tjandra, Sugih S.; Pudjaprasetya, S. R.

    2014-03-01

    Similar to the vibration of a guitar string or an elastic membrane, water waves in an enclosed basin undergo standing oscillatory waves, also known as seiches. The resonant (eigen) periods of seiches are determined by water depth and geometry of the basin. For regular basins, explicit formulas are available. Resonance occurs when the dominant frequency of external force matches the eigen frequency of the basin. In this paper, we implement the conservative finite volume scheme to 2D shallow water equation to simulate resonance in closed basins. Further, we would like to use this scheme and utilizing energy spectra of the recorded signal to extract resonant periods of arbitrary basins. But here we first test the procedure for getting resonant periods of a square closed basin. The numerical resonant periods that we obtain are comparable with those from analytical formulas.

  10. Frequency scaling for angle gathers

    KAUST Repository

    Zuberi, M. A H

    2014-01-01

    Angle gathers provide an extra dimension to analyze the velocity after migration. Space-shift and time shift-imaging conditions are two methods used to obtain angle gathers, but both are reasonably expensive. By scaling the time-lag axis of the time-shifted images, the computational cost of the time shift imaging condition can be considerably reduced. In imaging and more so Full waveform inversion, frequencydomain Helmholtz solvers are used more often to solve for the wavefields than conventional time domain extrapolators. In such cases, we do not need to extend the image, instead we scale the frequency axis of the frequency domain image to obtain the angle gathers more efficiently. Application on synthetic data demonstrate such features.

  11. The radio-frequency quadrupole

    CERN Document Server

    Vretenar, Maurizio

    2013-01-01

    Radio-frequency quadrupole (RFQ) linear accelerators appeared on the accelerator scene in the late 1970s and have since revolutionized the domain of low-energy proton and ion acceleration. The RFQ makes the reliable production of unprecedented ion beam intensities possible within a compact radio-frequency (RF) resonator which concentrates the three main functions of the low-energy linac section: focusing, bunching and accelerating. Its sophisticated electrode structure and strict beam dynamics and RF requirements, however, impose severe constraints on the mechanical and RF layout, making the construction of RFQs particularly challenging. This lecture will introduce the main beam optics, RF and mechanical features of a RFQ emphasizing how these three aspects are interrelated and how they contribute to the final performance of the RFQ.

  12. High-Frequency Seafloor Acoustics

    CERN Document Server

    Jackson, Darrell R

    2007-01-01

    High-Frequency Seafloor Acoustics is the first book in a new series sponsored by the Office of Naval Research on the latest research in underwater acoustics. This exciting new title provides ready access to experimental data, theory, and models relevant to high-frequency seafloor acoustics and will be of interest to sonar engineers and researchers working in underwater acoustics. The physical characteristics of the seafloor affecting acoustic propagation and scattering are covered, including physical and geoacoustic properties and surface roughness. Current theories for acoustic propagation in sediments are presented along with corresponding models for reflection, scattering, and seafloor penetration. The main text is backed up by an extensive bibliography and technical appendices.

  13. Dermatomycosis Frequency and Localization Sites

    OpenAIRE

    Koçinaj, Allma Ferizi; Kotori, Merita Grajqevci; Koraqi, Andi; Fida, Monika

    2015-01-01

    Introduction: Since the prevalence of skin mycotic infections is changing and is area depended we aimed to analyze the frequency of the skin myocotic infections and the appearance sites. Material and Methods: There were involved 560 patients referred to the Dermatology Clinic of University Clinical Center of Kosova during a period of one year. Results: The mean age of our study group was around thirties with a predominance of female and rural patients. Although most of cases presented with si...

  14. LEP Radio Frequency Copper Cavity

    CERN Multimedia

    The pulse of a particle accelerator. 128 of these radio frequency cavities were positioned around CERN's 27-kilometre LEP ring to accelerate electrons and positrons. The acceleration was produced by microwave electric oscillations at 352 MHz. The electrons and positrons were grouped into bunches, like beads on a string, and the copper sphere at the top stored the microwave energy between the passage of individual bunches. This made for valuable energy savings as it reduced the heat generated in the cavity.

  15. High frequency trading and fragility

    OpenAIRE

    Cespa, Giovanni; Vives, Xavier

    2017-01-01

    We show that limited dealer participation in the market, coupled with an informational friction resulting from high frequency trading, can induce demand for liquidity to be upward sloping and strategic complementarities in traders’ liquidity consumption decisions: traders demand more liquidity when the market becomes less liquid, which in turn makes the market more illiquid, fostering the initial demand hike. This can generate market instability, where an initial dearth of liquidity degenerat...

  16. Polymorphic Mutation Frequencies of Clinical and Environmental Stenotrophomonas maltophilia Populations▿

    Science.gov (United States)

    Turrientes, María Carmen; Baquero, María Rosario; Sánchez, María Blanca; Valdezate, Sylvia; Escudero, Esther; Berg, Gabrielle; Cantón, Rafael; Baquero, Fernando; Galán, Juan Carlos; Martínez, José Luis

    2010-01-01

    Mutation frequencies were studied in 174 Stenotrophomonas maltophilia isolates from clinical and nonclinical environments by detecting spontaneous rifampin-resistant mutants in otherwise-susceptible populations. The distribution of mutation frequencies followed a pattern similar to that found for other bacterial species, with a modal value of 1 × 10−8. Nevertheless, the proportion of isolates showing mutation frequencies below the modal value (hypomutators) was significantly higher for S. maltophilia than those so far reported in other organisms. Low mutation frequencies were particularly frequent among environmental S. maltophilia strains (58.3%), whereas strong mutators were found only among isolates with a clinical origin. These results indicate that clinical environments might select bacterial populations with high mutation frequencies, likely by second-order selection processes. In several of the strong-mutator isolates, functional-complementation assays with a wild-type allele of the mutS gene demonstrated that the mutator phenotype was due to the impairment of MutS activity. In silico analysis of the amino acid changes present in the MutS proteins of these hypermutator strains in comparison with the normomutator isolates suggests that the cause of the defect in MutS might be a H683P amino acid change. PMID:20097818

  17. 47 CFR 74.802 - Frequency assignment.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Frequency assignment. 74.802 Section 74.802... Frequency assignment. (a) Frequencies within the following bands may be assigned for use by low power... exceed 200 kHz. (d) Low power auxiliary licensees will not be granted exclusive frequency assignments. (e...

  18. Automation of measurement frequency SVCh kolebany

    Directory of Open Access Journals (Sweden)

    A. A. Parfenov

    1987-12-01

    Full Text Available The functional diagram of the frequency meter, comprising a microprocessor controller and commercially available devices. An algorithm for calculating the frequency of the microprocessor used in determining the frequency SVChgeneratora. In the range of 52-79 GHz frequency provides direct reading with an absolute error of less than 2 MHz.

  19. 47 CFR 101.803 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 101.803 Section 101.803... SERVICES Local Television Transmission Service § 101.803 Frequencies. (a) Frequencies in the following...,300 MHz. (7) Notes (1) This frequency band is shared with fixed and mobile stations licensed...

  20. 47 CFR 87.303 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.303 Section 87.303... Flight Test Stations § 87.303 Frequencies. (a) These frequencies are available for assignment to flight....375 3 123.450 3 (b) These additional frequencies are available for assignment only to flight...

  1. 47 CFR 80.45 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 80.45 Section 80.45... MARITIME SERVICES Applications and Licenses § 80.45 Frequencies. For applications other than ship stations, the applicant must propose frequencies and ensure that those requested frequencies are consistent...

  2. 47 CFR 18.301 - Operating frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operating frequencies. 18.301 Section 18.301... Standards § 18.301 Operating frequencies. ISM equipment may be operated on any frequency above 9 kHz except as indicated in § 18.303. The following frequency bands, in accordance with § 2.106 of the rules,...

  3. 47 CFR 87.195 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.195 Section 87.195... Aircraft Stations Emergency Locator Transmitters § 87.195 Frequencies. (a) ELTs transmit on the frequency 121.500 MHz, using A3E, A3X or NON emission. ELTs that transmit on the frequency 406.0-406.1 MHz...

  4. 47 CFR 24.129 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Frequencies. 24.129 Section 24.129... SERVICES Narrowband PCS § 24.129 Frequencies. The following frequencies are available for narrowband PCS: (a) Eighteen frequencies are available for assignment on a nationwide basis as follows: (1) Seven...

  5. 47 CFR 87.349 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.349 Section 87.349... Aeronautical Utility Mobile Stations § 87.349 Frequencies. (a) The frequency assigned to an aeronautical... frequency used by the control tower for ground traffic control or by the flight service station...

  6. 47 CFR 87.475 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.475 Section 87.475... Stations in the Radiodetermination Service § 87.475 Frequencies. (a) Frequency coordination. The Commission will assign frequencies to radionavigation land stations and radionavigation land test stations...

  7. 47 CFR 95.1401 - Frequency.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequency. 95.1401 Section 95.1401... SERVICES Personal Locator Beacons (PLB). § 95.1401 Frequency. The frequency band 406.0-406.1 MHz is an emergency and distress frequency band available for use by Personal Locator Beacons (PLBs). Personal...

  8. 47 CFR 87.449 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.449 Section 87.449... Operational Fixed Stations § 87.449 Frequencies. The following frequencies in the 72-76 MHz band are... TV reception on Channels 4 and 5. These frequencies are shared with the Land Mobile and the...

  9. 47 CFR 80.375 - Radiodetermination frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Radiodetermination frequencies. 80.375 Section... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Radiodetermination § 80.375 Radiodetermination frequencies. This section describes the carrier frequencies assignable to radiodetermination stations....

  10. 47 CFR 87.217 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.217 Section 87.217... Aeronautical Advisory Stations (Unicoms) § 87.217 Frequencies. (a) Only one unicom frequency will be assigned at any one airport. Applicants must request a particular frequency, which will be taken...

  11. 47 CFR 87.187 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.187 Section 87.187... Aircraft Stations § 87.187 Frequencies. (a) Frequencies used for air-ground Communications are listed in subpart E. Aircraft stations may use frequencies assigned to Government or non-Government...

  12. 47 CFR 74.561 - Frequency tolerance.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Frequency tolerance. 74.561 Section 74.561... § 74.561 Frequency tolerance. In the bands above 944 MHz, the operating frequency of the transmitter shall be maintained in accordance with the following table: Frequency band (MHz) Tolerance as...

  13. Hyperbolic equations and frequency interactions

    CERN Document Server

    Caffarelli, Luis

    1998-01-01

    The research topic for this IAS/PCMI Summer Session was nonlinear wave phenomena. Mathematicians from the more theoretical areas of PDEs were brought together with those involved in applications. The goal was to share ideas, knowledge, and perspectives. How waves, or "frequencies", interact in nonlinear phenomena has been a central issue in many of the recent developments in pure and applied analysis. It is believed that wavelet theory-with its simultaneous localization in both physical and frequency space and its lacunarity-is and will be a fundamental new tool in the treatment of the phenomena. Included in this volume are write-ups of the "general methods and tools" courses held by Jeff Rauch and Ingrid Daubechies. Rauch's article discusses geometric optics as an asymptotic limit of high-frequency phenomena. He shows how nonlinear effects are reflected in the asymptotic theory. In the article "Harmonic Analysis, Wavelets and Applications" by Daubechies and Gilbert the main structure of the wavelet theory is...

  14. Auditory filters at low-frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Pedersen, Christian Sejer; Møller, Henrik

    2009-01-01

    Prediction and assessment of low-frequency noise problems requires information about the auditory filter characteristics at low-frequencies. Unfortunately, data at low-frequencies is scarce and practically no results have been published for frequencies below 100 Hz. Extrapolation of ERB results......-ear transfer function), the asymmetry of the auditory filter changed from steeper high-frequency slopes at 1000 Hz to steeper low-frequency slopes below 100 Hz. Increasing steepness at low-frequencies of the middle-ear high-pass filter is thought to cause this effect. The dynamic range of the auditory filter...

  15. High-frequency Oligonucleotides in Watermelon Expressed Sequenced Tag-unigenes Are Useful in Producing Polymorphic Polymerase Chain Reaction Markers among Watermelon Genotypes

    Science.gov (United States)

    In this study, we report a simple procedure for developing gene targeted primers, named high-frequency gene sequence (HFGS) primers, based on oligonucleotides that exist in high frequency in watermelon expressed sequence tag (EST)-unigenes. These HFGS primers were constructed by first screening for...

  16. DREB genes

    African Journals Online (AJOL)

    Unipar

    2015-03-12

    Mar 12, 2015 ... to AP2/ERF family, dehydration-responsive element-binding protein (DREB) genes, (CitsERF01 to ... Protein sequences of DREB subfamilies belonging to group I, .... position 37, and it was present in consensus in all protein.

  17. Fast frequency divider circuit using combinational logic

    Science.gov (United States)

    Helinski, Ryan

    2017-05-30

    The various technologies presented herein relate to performing on-chip frequency division of an operating frequency of a ring oscillator (RO). Per the various embodiments herein, a conflict between RO size versus operational frequency can be addressed by dividing the output frequency of the RO to a frequency that can be measured on-chip. A frequency divider circuit (comprising NOR gates and latches, for example) can be utilized in conjunction with the RO on the chip. In an embodiment, the frequency divider circuit can include a pair of latches coupled to the RO to facilitate dividing the oscillating frequency of the RO by 2. In another embodiment, the frequency divider circuit can include four latches (operating in pairs) coupled to the RO to facilitate dividing the oscillating frequency of the RO by 4. A plurality of ROs can be MUXed to the plurality of ROs by a single oscillation-counting circuit.

  18. New Mixer Used in Direct Frequency Synthesizer

    Directory of Open Access Journals (Sweden)

    Milan Stork

    2008-01-01

    Full Text Available Frequency synthesizers are an essential part of any modern transceiver system. They generate clock and oscillator signals needed for up and down conversion. Today’s communication standards demand both high frequency accuracy and fast frequency settling. The fine frequency resolution, low spurious signals, accuracy and stability are most important for these devices. In this paper, the new frequency synthesizer architecture based on direct synthesis and coincidence mixer is presented. The simulation results are also shown.

  19. Recognizing frequency characteristics of gas sensor array

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel method based on independent component analyzing (ICA) in frequency domain to distinguish the frequency characteristics of multi-sensor system is presented. The conditions of this type of ICA are considered and each step of resolving the problem is discussed. For a two gas sensor array, the frequency characteristics including amplitude-frequency and phase-frequency are recognized by this method, and cross-sensitivity between them is also eliminated. From the principle of similarity, the recognition m...

  20. Gene expression in colorectal cancer

    DEFF Research Database (Denmark)

    Birkenkamp-Demtroder, Karin; Christensen, Lise Lotte; Olesen, Sanne Harder

    2002-01-01

    Understanding molecular alterations in colorectal cancer (CRC) is needed to define new biomarkers and treatment targets. We used oligonucleotide microarrays to monitor gene expression of about 6,800 known genes and 35,000 expressed sequence tags (ESTs) on five pools (four to six samples in each p...... with a high frequency of loss of heterozygosity. The genes and ESTs presented in this study encode new potential tumor markers as well as potential novel therapeutic targets for prevention or therapy of CRC.......Understanding molecular alterations in colorectal cancer (CRC) is needed to define new biomarkers and treatment targets. We used oligonucleotide microarrays to monitor gene expression of about 6,800 known genes and 35,000 expressed sequence tags (ESTs) on five pools (four to six samples in each...... pool) of total RNA from left-sided sporadic colorectal carcinomas. We compared normal tissue to carcinoma tissue from Dukes' stages A-D (noninvasive to distant metastasis) and identified 908 known genes and 4,155 ESTs that changed remarkably from normal to tumor tissue. Based on intensive filtering 226...

  1. Gene Polymorphisms in Chronic Periodontitis

    Directory of Open Access Journals (Sweden)

    Marja L. Laine

    2010-01-01

    Full Text Available We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP.

  2. Semantic particularity measure for functional characterization of gene sets using gene ontology.

    Science.gov (United States)

    Bettembourg, Charles; Diot, Christian; Dameron, Olivier

    2014-01-01

    Genetic and genomic data analyses are outputting large sets of genes. Functional comparison of these gene sets is a key part of the analysis, as it identifies their shared functions, and the functions that distinguish each set. The Gene Ontology (GO) initiative provides a unified reference for analyzing the genes molecular functions, biological processes and cellular components. Numerous semantic similarity measures have been developed to systematically quantify the weight of the GO terms shared by two genes. We studied how gene set comparisons can be improved by considering gene set particularity in addition to gene set similarity. We propose a new approach to compute gene set particularities based on the information conveyed by GO terms. A GO term informativeness can be computed using either its information content based on the term frequency in a corpus, or a function of the term's distance to the root. We defined the semantic particularity of a set of GO terms Sg1 compared to another set of GO terms Sg2. We combined our particularity measure with a similarity measure to compare gene sets. We demonstrated that the combination of semantic similarity and semantic particularity measures was able to identify genes with particular functions from among similar genes. This differentiation was not recognized using only a semantic similarity measure. Semantic particularity should be used in conjunction with semantic similarity to perform functional analysis of GO-annotated gene sets. The principle is generalizable to other ontologies.

  3. Metagenome Fragment Classification Using -Mer Frequency Profiles

    Directory of Open Access Journals (Sweden)

    Gail Rosen

    2008-01-01

    Full Text Available A vast amount of microbial sequencing data is being generated through large-scale projects in ecology, agriculture, and human health. Efficient high-throughput methods are needed to analyze the mass amounts of metagenomic data, all DNA present in an environmental sample. A major obstacle in metagenomics is the inability to obtain accuracy using technology that yields short reads. We construct the unique -mer frequency profiles of 635 microbial genomes publicly available as of February 2008. These profiles are used to train a naive Bayes classifier (NBC that can be used to identify the genome of any fragment. We show that our method is comparable to BLAST for small 25 bp fragments but does not have the ambiguity of BLAST's tied top scores. We demonstrate that this approach is scalable to identify any fragment from hundreds of genomes. It also performs quite well at the strain, species, and genera levels and achieves strain resolution despite classifying ubiquitous genomic fragments (gene and nongene regions. Cross-validation analysis demonstrates that species-accuracy achieves 90% for highly-represented species containing an average of 8 strains. We demonstrate that such a tool can be used on the Sargasso Sea dataset, and our analysis shows that NBC can be further enhanced.

  4. Plant Responses to High Frequency Electromagnetic Fields

    Directory of Open Access Journals (Sweden)

    Alain Vian

    2016-01-01

    Full Text Available High frequency nonionizing electromagnetic fields (HF-EMF that are increasingly present in the environment constitute a genuine environmental stimulus able to evoke specific responses in plants that share many similarities with those observed after a stressful treatment. Plants constitute an outstanding model to study such interactions since their architecture (high surface area to volume ratio optimizes their interaction with the environment. In the present review, after identifying the main exposure devices (transverse and gigahertz electromagnetic cells, wave guide, and mode stirred reverberating chamber and general physics laws that govern EMF interactions with plants, we illustrate some of the observed responses after exposure to HF-EMF at the cellular, molecular, and whole plant scale. Indeed, numerous metabolic activities (reactive oxygen species metabolism, α- and β-amylase, Krebs cycle, pentose phosphate pathway, chlorophyll content, terpene emission, etc. are modified, gene expression altered (calmodulin, calcium-dependent protein kinase, and proteinase inhibitor, and growth reduced (stem elongation and dry weight after low power (i.e., nonthermal HF-EMF exposure. These changes occur not only in the tissues directly exposed but also systemically in distant tissues. While the long-term impact of these metabolic changes remains largely unknown, we propose to consider nonionizing HF-EMF radiation as a noninjurious, genuine environmental factor that readily evokes changes in plant metabolism.

  5. Gene Flow and the Measurement of Dispersal in Plant Populations.

    Science.gov (United States)

    Nicholls, Marc S.

    1986-01-01

    Reviews methods of estimating pollen and seed dispersals and discusses the extent and frequency of gene exchange within and between populations. Offers suggestions for designing exercises suitable for estimating dispersal distances in natural plant populations. (ML)

  6. High-frequency submicrosecond electroporator

    Directory of Open Access Journals (Sweden)

    Vitalij Novickij

    2016-05-01

    Full Text Available In this work, we present a novel electroporator which is capable of generating single and bursts of high power (3 kV, 60 A square wave pulses of variable duration (100 ns to 1 ms with predefined repetition frequency (1 Hz to 3.5 MHz. The proposed synchronized crowbar implementation ensures a constant pulse rise and fall times, which are independent from the load, thus highly relevant in electroporation. The electroporator was successfully tested for the inactivation of the human pathogen Candida albicans. The device is compatible with standard commercial electroporation cuvettes.

  7. High-frequency magnetic components

    CERN Document Server

    Kazimierczuk, Marian K

    2013-01-01

    A unique text on the theory and design fundaments of inductors and transformers, updated with more coverage on the optimization of magnetic devices and many new design examples The first edition is popular among a very broad audience of readers in different areas of engineering and science. This book covers the theory and design techniques of the major types of high-frequency power inductors and transformers for a variety of applications, including switching-mode power supplies (SMPS) and resonant dc-to-ac power inverters and dc-to-dc power converters. It describes eddy-current phenomena (su

  8. Graphene for radio frequency electronics

    Directory of Open Access Journals (Sweden)

    Lei Liao

    2012-07-01

    Full Text Available Graphene is emerging as an attractive electronic material for future electronics. With the highest carrier mobility, high saturation velocity, high critical current densities, and single atomic thickness, graphene has great potential for ultra-high speed transistors, with the highest projected cut-off frequency exceeding 1 THz. However, the fabrication of high speed graphene transistors is of significant challenge, since conventional electronic fabrication processes often introduce undesirable defects into graphene lattices. Significant efforts have made to mitigate these challenges. Here we review the opportunities, challenges, as well as the recent advances in the development of high speed graphene transistors and circuits.

  9. Radio frequency integrated circuit design

    CERN Document Server

    Rogers, John W M

    2010-01-01

    This newly revised and expanded edition of the 2003 Artech House classic, Radio Frequency Integrated Circuit Design, serves as an up-to-date, practical reference for complete RFIC know-how. The second edition includes numerous updates, including greater coverage of CMOS PA design, RFIC design with on-chip components, and more worked examples with simulation results. By emphasizing working designs, this book practically transports you into the authors' own RFIC lab so you can fully understand the function of each design detailed in this book. Among the RFIC designs examined are RF integrated LC

  10. Angiogenin gene polymorphism

    Institute of Scientific and Technical Information of China (English)

    Hongli Wang; Dongsheng Fan; Yingshuang Zhang

    2013-01-01

    Angiogenin is associated with the pathogenesis of diabetic peripheral neuropathy. Here, we se-quenced the coding region of the angiogenin gene in genomic DNA from 207 patients with type 2 diabetes mel itus (129 diabetic peripheral neuropathy patients and 78 diabetic non-neuropathy pa-tients) and 268 healthy controls. Al subjects were from the Han population of northern China. No mutations were found. We then compared the genotype and allele frequencies of the angiogenin synonymous single nucleotide polymorphism rs11701 between the diabetic peripheral neuropathy patients and controls, and between the diabetic neuropathy and non-neuropathy patients, using a case-control design. We detected no statistical y significant genetic associations. Angiogenin may not be associated with genetic susceptibility to diabetic peripheral neuropathy in the Han population of northern China.

  11. Endothelial Genes

    Science.gov (United States)

    2005-06-01

    8217Department of Surgery, Division of Oncology , and 2Department of BRCA-l and BRCA-2 (breast cancer susceptibility genes), Pathology, University of...Suppression subtractive hybridization re- Cancer: principles and practice of oncology . Philadelphia: Lippincott- vealed an RNA sequence (GenBank accession...Lippman ME. Cancer of the breast: molecular biology angiogenesis in sarcomas and carcinomas. Clin Cancer Res 1999;5: of breast cancer. In: DeVita VT

  12. Gene Ontology

    Directory of Open Access Journals (Sweden)

    Gaston K. Mazandu

    2012-01-01

    Full Text Available The wide coverage and biological relevance of the Gene Ontology (GO, confirmed through its successful use in protein function prediction, have led to the growth in its popularity. In order to exploit the extent of biological knowledge that GO offers in describing genes or groups of genes, there is a need for an efficient, scalable similarity measure for GO terms and GO-annotated proteins. While several GO similarity measures exist, none adequately addresses all issues surrounding the design and usage of the ontology. We introduce a new metric for measuring the distance between two GO terms using the intrinsic topology of the GO-DAG, thus enabling the measurement of functional similarities between proteins based on their GO annotations. We assess the performance of this metric using a ROC analysis on human protein-protein interaction datasets and correlation coefficient analysis on the selected set of protein pairs from the CESSM online tool. This metric achieves good performance compared to the existing annotation-based GO measures. We used this new metric to assess functional similarity between orthologues, and show that it is effective at determining whether orthologues are annotated with similar functions and identifying cases where annotation is inconsistent between orthologues.

  13. Alpha-thalassemia in northern Thailand. Frequency of deletional types characterized at the DNA level.

    Science.gov (United States)

    Hundrieser, J; Sanguansermsri, T; Papp, T; Flatz, G

    1988-01-01

    The frequency of alpha-thalassemias in northern Thailand was estimated using DNA techniques. Among 106 healthy adult Thais from the Chiangmai area, 28 were shown to carry alpha-globin gene anomalies. There were 19 heterozygotes and 1 homozygote for alpha-thalassemia-2. One of the alpha-thalassemia-2 deletions was of the -alpha 4.2 type and the remaining 20 of the -alpha 3.7 type (subtype I). Deletions of both alpha-globin genes on one chromosome (alpha-thalassemia-1) of the Southeast Asian type were observed in 5 cases, and 3 alpha-globin gene triplications were identified. Compared with a previous report on alpha-thalassemia in northern Thailand which was based on the determination of hemoglobin Bart's in cord blood, the present DNA study reveals a similar frequency of alpha-thalassemia-2 but a considerably lower frequency of alpha-thalassemia-1.

  14. 78 FR 45479 - Frequency Response and Frequency Bias Setting Reliability Standard

    Science.gov (United States)

    2013-07-29

    ... Energy Regulatory Commission 18 CFR Part 40 Frequency Response and Frequency Bias Setting Reliability...: The Commission proposes to approve Reliability Standard BAL- 003-1 (Frequency Response and Frequency... of frequency response needed for reliable operations for each Balancing Authority within...

  15. A Novel Frequency Measurement Method Suitable for a Large Frequency Ratio Condition

    Institute of Scientific and Technical Information of China (English)

    ZHOU Wei; XUAN Zong-Qiang; YU Jian-Guo; WANG Hai; ZHOU Hui; LI Zhi-Qi

    2004-01-01

    @@ As for the obstacles to direct comparison between superhigh and lower frequencies, we accomplish the accurate comparison between low and microwave frequencies with the 105 ratios of the operating frequencies on the basis of phase comparison between the signals whose frequencies are related by an arbitrary integer. This method is simple and accurate, and will be widely used as a special frequency comparison approach.

  16. Multi-frequency imaging in VLBI

    CERN Document Server

    Likhachev, S

    2004-01-01

    The new technique, multi-frequency imaging (MFI) is developed. In VLBI, Multi-Frequency Imaging (MFI) consists of multi-frequency synthesis (MFS) and multi-frequency analysis (MFA) of the VLBI data obtained from observations on various frequencies. A set of linear deconvolution MFI algorithms is described. The algorithms make it possible to obtain high quality images interpolated on any given frequency inside any given bandwidth, and to derive reliable estimates of spectral indexes for radio sources with continuum spectrum. Thus MFI approach makes it is possible not only to improve the quality and fidelity of the images and also essentially to derive the morphology of the observed radio sources.

  17. Establishment and verification of dose effect relation curves between T cell receptor gene mutation frequency and ionizing radiation dose%电离辐射与T细胞突变频率的剂量效应关系曲线的建立与验证

    Institute of Scientific and Technical Information of China (English)

    马娅; 侯殿俊; 刘伟; 李洁清; 周桂珍; 乔建维; 封丽

    2011-01-01

    Objective To establish the dose-effect curve between TCR MF and ionizing radiation.Methods Peripheral lymphocytes were collected from 8 healthy adults(4 males and 4 females) and cultured in vitro with 12 well culture plates.They were stimulated by PHA-P and IL-2 after exposed to different doses of irradiation (0.00 -8.00 Gy) and cultured for 7 d.The dose-effect curve was established after measuring TCR MF using flow cytometry.Also,using the same method,we separated and cultured the peripheral lymphocytes collected from 16 radiotherapy cancer patients,whose radiation styles and doses were different,and then measured TCR MF to estimate the whole equivalent dose of radiotherapy patients through the dose-effect curve.Peripheral blood was collected and cultured,chromosome aberration (dicentric and ring) was determined under microscope to estimate irradiation dose.Results The relationship of dose-effect between the TCR MF and ionizing radiation (0.00 -8.00 Gy) was well,the curve of large dose group (2.00 -8.00 Gy),low dose group(0.00 - 1.00 Gy) and 0.00 -8.00 Gy dose group were met with the quadratic polynomial model,the equation was TCR MF =-32.8579 + 20.5436D + 0.6341D2,TCR MF =1.796 + 0.017D + 5.155D2 and TCR MF =- 0.6229 + 6.305D + 0.6919D2,respectively.D was the radiation dose ( Gy ).Using the established curve and the chromosome aberration method to estimate the systemic exposure dosage,the average relative deviation was 16.8%.Conclusion The curve established by the TCR gene mutation analysis technology can be applied to exposure dose eatimation of victims in ionization radiation accidents.%目的 建立T细胞受体基因突变频率(T cell receptor mutation frequency,TCR MF)与电离辐射剂量效应关系曲线.方法 招募8名健康成年人,4男4女.采集其外周血,分离淋巴细胞,分装到12孔培养板中,不同剂量(0.00~8.00 Gy)照射后,用植物血凝素蛋白(PHA-P)刺激,加人重组白介素-2(IL-2)培育7d,以流式细胞仪测量TCR MF

  18. High frequency of RPL22 mutations in microsatellite-unstable colorectal and endometrial tumors.

    Science.gov (United States)

    Ferreira, Ana M; Tuominen, Iina; van Dijk-Bos, Krista; Sanjabi, Bahram; van der Sluis, Tineke; van der Zee, Ate G; Hollema, Harry; Zazula, Monika; Sijmons, Rolf H; Aaltonen, Lauri A; Westers, Helga; Hofstra, Robert M W

    2014-12-01

    Ribosomal Protein L22 (RPL22) encodes a protein that is a component of the 60S subunit of the ribosome. Variants in this gene have recently been linked to cancer development. Mutations in an A8 repeat in exon 2 were found in a recent study in 52% of microsatellite-unstable endometrial tumors. These tumors are particularly prone to mutations in repeats due to mismatch repair deficiency. We screened this coding repeat in our collection of microsatellite-unstable endometrial tumors (EC) and colorectal tumors (CRC). We found 50% mutation frequency for EC and 77% mutation frequency for CRC. These results confirm the previous study on the involvement of RPL22 in EC and, more importantly, reports for the first time such high mutation frequency in this gene in colorectal cancer. Furthermore, considering the high mutation frequency found, our data point toward an important role for RPL22 in microsatellite instability carcinogenesis.

  19. Gene doping: gene delivery for olympic victory

    OpenAIRE

    2012-01-01

    With one recently recommended gene therapy in Europe and a number of other gene therapy treatments now proving effective in clinical trials it is feasible that the same technologies will soon be adopted in the world of sport by unscrupulous athletes and their trainers in so called ‘gene doping’. In this article an overview of the successful gene therapy clinical trials is provided and the potential targets for gene doping are highlighted. Depending on whether a doping gene product is secreted...

  20. Analysis of Polymorphism of Angiotensin System Genes (ACE, AGTR1, and AGT) and Gene ITGB3 in Patients with Arterial Hypertension in Combination with Metabolic Syndrome.

    Science.gov (United States)

    Zotova, T Yu; Kubanova, A P; Azova, M M; Aissa, A Ait; Gigani, O O; Frolov, V A

    2016-07-01

    Changes in the frequencies of genotypes and mutant alleles of ACE, AGTR1, AGT, and ITGB3 genes were analyzed in patients with arterial hypertension coupled with metabolic syndrome (N=15) and compared with population data and corresponding parameters in patients with isolated hypertension (N=15). Increased frequency of genotype ID of ACE gene (hypertension predictor) was confirmed for both groups. In case of isolated hypertension, M235M genotype (gene AGT) was more frequent, in case of hypertension combined with metabolic syndrome, the frequency of genotypes A1166C and C1166C of the gene AGTR1 was higher in comparison with population data. Comparison of mutant allele frequencies in the two groups showed that at the 90% significance level allele T of the AGT gene was more frequent in hypertension coupled with metabolic syndrome (OR=1.26) and genotype A1166A of the AGTR1 gene was more frequent in the group with isolated hypertension.