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	Provedor de dados Biol. Res. (11) Genet. Mol. Biol. (1) Autor Valenzuela,Carlos Y (12) Araya,Irene (1) Cisternas,Javier (1) Flores,Sergio V (1) Pincheira,Juana (1) Rodríguez,Natalie (1) Sazunic,Ivo (1) Zemelman,Viviana B (1) de la Torre,Consuelo (1) Mais... Palavra-chave Neutral evolution (3) Bose-Einstein distribution (2) Chile (2) DNA periodicity (2) Socioeconomic strata (2) ABO (1) Age at menarche (1) Annual rhythm (1) Anti-tumoral genotoxic drugs (1) Birth order (1) Circa-vacation-study-expectancy rhythm (1) DNA damage and repair (1) DNA organization (1) Dinucleotide analysis (1) Dinucleotides (1) England (1) Fetomoternal tolerance (1) Fiesta expectancy (1) Fixation (1) Fxations (1) Mais... Tipo do documento Journal article (11) Info:eu-repo/semantics/article (1) Ano 2014 (2) 2013 (3) 2012 (1) 2011 (2) 2010 (3) 2009 (1) Mais... País Chile (11) Brazil (1) Idioma Inglês (12)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 12 Primeira ... 1 ... Última Internucleotide correlations and nucleotide periodicity in Drosophila mtDNA: New evidence for panselective evolution Biol. Res. Valenzuela,Carlos Y. Analysis for the homogeneity of the distribution of the second base of dinucleotides in relation to the first, whose bases are separated by 0, 1, 2,... 21 nucleotide sites, was performed with the VIH-1 genome (cDNA), the Drosophila mtDNA, the Drosophila Torso gene and the human p-globin gene. These four DNA segments showed highly significant heterogeneities of base distributions that cannot be accounted for by neutral or nearly neutral evolution or by the "neighbor influence" of nucleotides on mutation rates. High correlations are found in the bases of dinucleotides separated by 0, 1 and more number of sites. A periodicity of three consecutive significance values (measured by the x²9) was found only in Drosophila mtDNA. This periodicity may be due to an... Tipo: Journal article Palavras-chave: Nucleotide heterogeneity; DNA periodicity; Dinucleotide analysis; Neutral evolution; Panselective evolution. Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000400014 Heterogeneous periodicity of drosophila mtDNA: new refutations of neutral and nearly neutral evolution Biol. Res. Valenzuela,Carlos Y. We found a consistent 3-site periodicity of the X²9 values for the heterogeneity of the distribution of the second base in relation to the first base of dinucleotides separated by 0 (contiguous), 1, 2, 3 ... 17 (K) nucleotide sites in Drosophila mtDNA. Triplets of X²9 values were found where the first was over 300 and the second and third ranged between 37 and 114 (previous studies). In this study, the periodicity was significant until separation of 2011K, and a structure of deviations from randomness among dinucleotides was found. The most deviant dinucleotides were G-G, G-C and C-G for the first, second and third element of the triplet, respectively. In these three cases there were more dinucleotides observed than expected. This inter-bases correlation... Tipo: Journal article Palavras-chave: DNA organization; Non-protein-coding evolution; Ordered nucleotide sequences; Inter-base associations; Refutation of neutralism. Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000300010 The monthly rhythm of incidence and age at menarche: thirty five years of research: The circa-vacation-study expectancy rhythm of incidence and age at menarche Biol. Res. Valenzuela,Carlos Y. The hypothesis that the vacation-study-expectancy scholar regime produces most of the monthly rhythm of the age at menarche (AaM) was tested. Studies on monthly menarche incidence (MI) refuted climatic factors as a main factor in this rhythm, and indicated that the main factor of this rhythm is the succession of expectancies of study (Stu-months) or vacation (Vac-months) months within a year. Thus the hypothesis of seasonal circa-annual rhythm should be modified to the circa-[vacation (fiesta)]-[study (non-fiesta)]-expectancies rhythm for the MI and age at menarche annual rhythms. In several countries Vac-months had higher MI than Stu-months. The high MI of Vac-months was followed by a large decrease when girls started their studies and a MI increase... Tipo: Journal article Palavras-chave: Age at menarche; Annual rhythm; Circa-vacation-study-expectancy rhythm; Fiesta expectancy; Menarche incidence. Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000100003 Sexual orientation, handedness, sex ratio and fetomaternal tolerance-rejection Biol. Res. Valenzuela,Carlos Y. Fraternal birth order (FBO) appears as a prenatal cause of 15% of homosexual males (gays) through mnemonic maternal anti-male factors. Non-right-handed men seem to be protected from homosexuality. Four hypotheses are proposed: (1) androgenic factors of non-right-handedness neutralize anti-male factors; (2) non-right-handedness and homosexuality are lethal or produce mental impairment; (3) non-right-handed male embryos are insensitive to anti-male factors; (4) mothers of non-right-handed fetuses do not produce anti-male factors. Studies of the sex ratio (SR) of older and younger siblings show: (1) a significant heterogeneity in the SR of siblings of right or non-right handed heterosexual men and women; (2) lesbians are born among siblings with high SR; (3)... Tipo: Journal article Palavras-chave: Homosexuality; Handedness; Sex ratio; Birth order; Fetomoternal tolerance; Genetic distortions. Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000300012 Response of the G2-prophase checkpoint to genotoxic drugs in lymphocytes from healthy individuals Biol. Res. Pincheira,Juana; de la Torre,Consuelo; Rodríguez,Natalie; Valenzuela,Carlos Y. We analyzed the in vitro effects of the anti-tumoral drugs doxorubicin, cytosine arabinoside and hydroxyurea on the G2-prophase checkpoint in lymphocytes from healthy individuals. At biologically equivalent concentrations, the induced DNA damage activated the corresponding checkpoint. Thus: i) there was a concentration-dependent delay of G2 time and an increase of both the total DNA lesions produced and repaired before metaphase and; ii) G2-checkpoint adaptation took place as chromosome aberrations (CAs) started to appear in the metaphase, indicating the presence of unrepaired double-strand breaks (DSBs) in the previous G2. The checkpoint ATM/ATR kinases are involved in DSB repair, since the recorded frequency of CAs increased when both kinases were... Tipo: Journal article Palavras-chave: DNA damage and repair; G2-prophase checkpoint adaptation; Premitotic DSBs and chromosomal aberrations; Anti-tumoral genotoxic drugs. Ano: 2012 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602012000200010 The structure of selective dinucleotide interactions and periodicities in D melanogaster mtDNA Biol. Res. Valenzuela,Carlos Y. BACKGROUND: We found a strong selective 3-sites periodicity of deviations from randomness of the dinucleotide (DN) distribution, where both bases of DN were separated by 1, 2, K sites in prokaryotes and mtDNA. Three main aspects are studied. I) the specific 3 K-sites periodic structure of the 16 DN. II) to discard the possibility that the periodicity was produced by the highly nonrandom interactive association of contiguous bases, by studying the interaction of non-contiguous bases, the first one chosen each I sites and the second chosen J sites downstream. III) the difference between this selective periodicity of association (distance to randomness) of the four bases with the described fixed periodicities of base sequences. RESULTS: I) The 16 pairs... Tipo: Journal article Palavras-chave: Dinucleotides; DNA periodicity; Periodicity structure; Selective interactions; Theories of evolution. Ano: 2014 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602014000100018 Foundational errors in the Neutral and Nearly-Neutral theories of evolution in relation to the Synthetic Theory: Is a new evolutionary paradigm necessary? Biol. Res. Valenzuela,Carlos Y. The Neutral Theory of Evolution (NTE) proposes mutation and random genetic drift as the most important evolutionary factors. The most conspicuous feature of evolution is the genomic stability during paleontological eras and lack of variation among taxa; 98% or more of nucleotide sites are monomorphic within a species. NTE explains this homology by random fixation of neutral bases and negative selection (purifying selection) that does not contribute either to evolution or polymorphisms. Purifying selection is insufficient to account for this evolutionary feature and the Nearly-Neutral Theory of Evolution (N-NTE) included negative selection with coefficients as low as mutation rate. These NTE and N-NTE propositions are thermodynamically (tendency to random... Tipo: Journal article Palavras-chave: Fixation; Loss; Neutral evolution; Polymorphism; Randomness; Selectiveness. Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000200001 Fixations of the HIV-1 env gene refute neutralism: New evidence for pan-selective evolution Biol. Res. Valenzuela,Carlos Y; Flores,Sergio V; Cisternas,Javier. We examined 103 nucleotide sequences of the HIV-1 env gene, sampled from 35 countries and tested: I) the random (neutral) distribution of the number of nucleotide changes; II) the proportion of bases at molecular equilibrium; III) the neutral expected homogeneity of the distribution of new fxated bases; IV) the hypothesis of the neighbor infuence on the mutation rates in a site. The expected random number of fxations per site was estimated by Bose-Einstein statistics, and the expected frequencies of bases by matrices of mutation-fxation rates. The homogeneity of new fxations was analyzed using &#967;2 and trinomial tests for homogeneity. Fixations of the central base in trinucleotides were used to test the neighbor infuence on base substitutions.... Tipo: Journal article Palavras-chave: Bose-Einstein distribution; Fxations; HIV-1 env gene; Neutral evolution; Pan-selective evolution. Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000200002 Letters to Editor / Erratum Biol. Res. Valenzuela,Carlos Y. Tipo: Journal article Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000300015 Malignant melanoma in Chile: different site distribution between private and state patients Biol. Res. Zemelman,Viviana B; Valenzuela,Carlos Y; Sazunic,Ivo; Araya,Irene. BACKGROUND: The body site location of primary Malignant Melanoma (MM) has been correlated with prognosis and survival. Ethnic, genetics, sun exposure factors are related to the anatomical distribution of MM. Low and high socioeconomic strata in Chile differ in ethnic, genetic and cultural conditions. The purpose of this study was to analyze the anatomical MM distribution in the Chilean population in both strata searching for differences due to their ethno-genetic-cultural differences. Records of 1148 MM, 575cases from state hospitals (Low Socioeconomic Strata, LSS) and 573 cases from private clinics (High Socioeconomic Strata, HSS) were analyzed by body site. RESULTS: Females from LSS showed a higher number of MM in soles, cheeks, and around the eye area.... Tipo: Journal article Palavras-chave: Chile; Malignant melanoma; Site distribution; Socioeconomic strata. Ano: 2014 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602014000100034 Human Sociogenetics Biol. Res. Valenzuela,Carlos Y. In three cities of Chile (Santiago, Valparaiso, Valdivia) the A allele and phenotype (ABO blood group) are more frequent in the higher socioeconomic strata (SES) and the O allele and phenotype are in the lower ones. This constitutes a structured sociogenetic cline (SGC). The B allele and phenotypes (B+AB) present a rather erratic or contradictory distribution among SES. This SGC was also found in England. The standard interpretation of the origin and maintenance of this SGC in Chile is founded on socio-ethno-historic-cultural and drift factors followed by socioeconomic assortative mating that has occurred since the origin of Chileans by the admixture of Europeans and Amerindians. This interpretation is insufficient to explain the coincidence of the cline... Tipo: Journal article Palavras-chave: ABO; Chile; England; Rh; Socioeconomic strata; Sociogenetics. Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000400012 Non-random pre-transcriptional evolution in HIV-1: a refutation of the foundational conditions for neutral evolution Genet. Mol. Biol. Valenzuela,Carlos Y. The complete base sequence of HIV-1 virus and GP120 ENV gene were analyzed to establish their distance to the expected neutral random sequence. An especial methodology was devised to achieve this aim. Analyses included: a) proportion of dinucleotides (signatures); b) homogeneity in the distribution of dinucleotides and bases (isochores) by dividing both segments in ten and three sub-segments, respectively; c) probability of runs of bases and No-bases according to the Bose-Einstein distribution. The analyses showed a huge deviation from the random distribution expected from neutral evolution and neutral-neighbor influence of nucleotide sites. The most significant result is the tremendous lack of CG dinucleotides (p < 10-50), a selective trait of... Tipo: Info:eu-repo/semantics/article Palavras-chave: Non-random evolution; HIV-1; Bose-Einstein distribution; Pre-transcriptional evolution; Non-random sequences. Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000100025 Registros recuperados: 12 Primeira ... 1 ... Última

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