1,025 research outputs found

    Origin and evolution of "Mytilus" mussel satellite DNAs

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    [Abstract] A phylogenetic reconstruction based on the amplification of 3 satellite DNAs (stDNAs) was carried out in 1 crustacean species and 15 bivalve species of the subclass Pteriomorphia (10, subfamily Mytilinae; 1, subfamily Litophaginae; 1, subfamily Modiolinae, all belonging to family Mytilidae; 1, family Arcidae; and 2, family Pectinidae). The sequences obtained showed motifs with high similarity to those of A and B boxes of tRNA promoter regions. Dot-blot hybridizations revealed that the 3 stDNAs are present mainly in high copy numbers for each species of the genus Mytilus, whereas for the other species they appear in low copy numbers. Maximum-parsimony trees evidenced a tendency to group Mytilus clones together, and species containing these sequences as a single copy were distributed among the different mytilids. Finally, the possible origin and evolution of these stDNAs is discussed.Xunta de Galicia; 10302B97Comisión Interministerial de Ciencia y Tecnología (I+D); ALI97-043

    Molecular organization and phylogenetic analysis of 5S rDNA in crustaceans of the genus Pollicipes reveal birth-and-death evolution and strong purifying selection

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    <p>Abstract</p> <p>Background</p> <p>The 5S ribosomal DNA (5S rDNA) is organized in tandem arrays with repeat units that consist of a transcribing region (5S) and a variable nontranscribed spacer (NTS), in higher eukaryotes. Until recently the 5S rDNA was thought to be subject to concerted evolution, however, in several taxa, sequence divergence levels between the 5S and the NTS were found higher than expected under this model. So, many studies have shown that birth-and-death processes and selection can drive the evolution of 5S rDNA. In analyses of 5S rDNA evolution is found several 5S rDNA types in the genome, with low levels of nucleotide variation in the 5S and a spacer region highly divergent. Molecular organization and nucleotide sequence of the 5S ribosomal DNA multigene family (5S rDNA) were investigated in three <it>Pollicipes </it>species in an evolutionary context.</p> <p>Results</p> <p>The nucleotide sequence variation revealed that several 5S rDNA variants occur in <it>Pollicipes </it>genomes. They are clustered in up to seven different types based on differences in their nontranscribed spacers (NTS). Five different units of 5S rDNA were characterized in <it>P. pollicipes </it>and two different units in <it>P. elegans </it>and <it>P. polymerus</it>. Analysis of these sequences showed that identical types were shared among species and that two pseudogenes were present. We predicted the secondary structure and characterized the upstream and downstream conserved elements. Phylogenetic analysis showed an among-species clustering pattern of 5S rDNA types.</p> <p>Conclusions</p> <p>These results suggest that the evolution of <it>Pollicipes </it>5S rDNA is driven by birth-and-death processes with strong purifying selection.</p

    Violence against women in politics: the case of the Mexico city's constituent assembly

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    The implementation of gender quotas and parity policies led to more women in politics. However, these have been associated to an increase, or at least higher recognition, of violence against them. This phenomenon has been referred tocaso as political violence, political violence against women, gender-based political violence, and political harassment. The lack of consensus on both the name and its conceptualization has entailed legislative gaps and failures in prevention, assistance and sanction mechanisms. This study contributes to this conceptual debate by proposing the term gender-based violence against women in politics and examines the experiences of female representatives in the Constituent Assembly of Mexico City. Females in politics experience a myriad of expressions of violence that are often not recognized as such. Not only male and female peers are responsible of harassing, discriminating and exerting violence, but also constituents, security personnel and employees of the Constituent Assembly. Women display an array of individual and collective resistance strategies. Implications on legislative reforms and policies aimed at preventing and sanctioning gender-based violence are discussed.The implementation of gender quotas and parity policies led to more women in politics. However, these have been associated to an increase, or at least higher recognition, of violence against them. This phenomenon has been referred tocaso as political violence, political violence against women, gender-based political violence, and political harassment. The lack of consensus on both the name and its conceptualization has entailed legislative gaps and failures in prevention, assistance and sanction mechanisms. This study contributes to this conceptual debate by proposing the term gender-based violence against women in politics and examines the experiences of female representatives in the Constituent Assembly of Mexico City. Females in politics experience a myriad of expressions of violence that are often not recognized as such. Not only male and female peers are responsible of harassing, discriminating and exerting violence, but also constituents, security personnel and employees of the Constituent Assembly. Women display an array of individual and collective resistance strategies. Implications on legislative reforms and policies aimed at preventing and sanctioning gender-based violence are discussed

    Interaction between IGF1 and IGFBPs in bovine cystic ovarian disease

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    Cystic ovarian disease (COD) is one of the main factors responsible for reproductive disorders in cattle. Although the pathogenesis and mechanism of cyst formation are not fully understood, it has been proposed that the IGF system could play an essential role, as it is a key intraovarian regulator. The aim of the present study was to determine whether the altered levels in IGF1 detected in bovines with COD are associated with changes at mRNA level or with differential modulation by IGFBPs. The mRNA levels of the IGF components studied were analyzed by real time PCR and in situ hybridization, and IGFBP expression and activity were assayed by immunohistochemistry and ligand blot, respectively. Results showed a decreased IGF1 mRNA level due to a lower granulosa cell gene expression in cystic follicles (P menor 0.05). Results also showed variations in IGFBP expression in the intraovarian cellular compartment and concentration in follicular fluid, and suggest that IGFBP3 is a key regulator of intrafollicular IGF1 in animals with COD.Fil: Rodríguez, Fernanda Mariel. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfologicas. Laboratorio de Biologia Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Salvetti, Natalia Raquel. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfologicas. Laboratorio de Biologia Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Colombero, M.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfologicas. Laboratorio de Biologia Celular y Molecular; ArgentinaFil: Stangaferro, M.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Barbeito, Claudio Gustavo. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Ortega, Hugo Hector. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfologicas. Laboratorio de Biologia Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Rey, Florencia. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfologicas. Laboratorio de Biologia Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentin

    Interaction between IGF1 and IGFBPs in bovine cystic ovarian disease

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    Cystic ovarian disease (COD) is one of the main factors responsible for reproductive disorders in cattle. Although the pathogenesis and mechanism of cyst formation are not fully understood, it has been proposed that the IGF system could play an essential role, as it is a key intraovarian regulator. The aim of the present study was to determine whether the altered levels in IGF1 detected in bovines with COD are associated with changes at mRNA level or with differential modulation by IGFBPs. The mRNA levels of the IGF components studied were analyzed by real time PCR and in situ hybridization, and IGFBP expression and activity were assayed by immunohistochemistry and ligand blot, respectively. Results showed a decreased IGF1 mRNA level due to a lower granulosa cell gene expression in cystic follicles (P menor 0.05). Results also showed variations in IGFBP expression in the intraovarian cellular compartment and concentration in follicular fluid, and suggest that IGFBP3 is a key regulator of intrafollicular IGF1 in animals with COD.Facultad de Ciencias Veterinaria

    Comparative analysis of different satellite DNAs in four Mytilus species

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    [Abstract:] We report the characterization of three satellite DNAs in four species of mussel: Mytilus edulis, Mytilus galloprovincialis, Mytilus trossulus, and Mytilus californianus. The monomers of the Apa I satellite DNAs were 173, 161, and 166 bp long. These satellite monomers were used to construct phylogenetic trees to infer relationships among these species. The topologies obtained clearly indicate that M. californianus is the most divergent species with respect to the other three. Furthermore, localization of satellite DNAs on metaphase chromosomes was performed using fluorescent in situ hybridization (FISH). Fluorescent signals revealed a different organization and distribution of these three satellite DNAs.Ministerio de Ciencia y Tecnología; 1FD97-1295España. Dirección General de Enseñanza Superior; PB97-1136Catalunya. Direcció General de Recerca; SGR99-18

    Molecular evolutionary characterization of the mussel "Mytilus" histone multigene family: first record of a tandemly repeated unit of five histone genes containing an H1 subtype with orphon features

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    [Abstract] The present work represents the first characterization of a clustered histone repetitive unit containing an H1 gene in a bivalve mollusk. To complete the knowledge on the evolutionary history of the histone multigene family in invertebrates, we undertake its characterization in five mussel Mytilus species, as an extension of our previous work on the H1 gene family. We report the quintet H4–H2B–H2A–H3–H1 as the major organization unit in the genome of Mytilus galloprovincialis with two 5S rRNA genes with interspersed nontranscribed spacer segments linked to the unit, which is not justified by their cotranscription with histone genes. Surprisingly, 3′ UTR regions of histone genes show two different mRNA termination signals, a stem-loop and a polyadenylation signal, both related to the evolution of histone gene expression patterns throughout the cell cycle. The clustered H1 histones characterized share essential features with “orphon” H1 genes, suggesting a common evolutionary origin for both histone subtypes which is supported by the reconstructed phylogeny for H1 genes. The characterization of histone genes in four additional Mytilus species revealed the presence of strong purifying selection acting among the members of the family. The chromosomal location of most of the core histone genes studied was identified by FISH close to telomeric regions in M. galloprovincialis. Further analysis on nucleotide variation would be necessary to assess if H1 proteins evolve according to the birth-and-death model of evolution and if the effect of the strong purifying selection maintaining protein homogeneity could account for the homologies detected between clustered and “orphon” variants.Xunta de Galicia; 10PX110304P

    Impact of neurodegenerative diseases on human adult hippocampal neurogenesis

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    Disrupted hippocampal performance underlies psychiatric comorbidities and cognitive impairments in patients with neurodegenerative disorders. To understand the contribution of adult hippocampal neurogenesis (AHN) to amyotrophic lateral sclerosis, Huntington's disease, Parkinson's disease, dementia with Lewy bodies, and frontotemporal dementia, we studied postmortem human samples. We found that adult-born dentate granule cells showed abnormal morphological development and changes in the expression of differentiation markers. The ratio of quiescent to proliferating hippocampal neural stem cells shifted, and the homeostasis of the neurogenic niche was altered. Aging and neurodegenerative diseases reduced the phagocytic capacity of microglia, triggered astrogliosis, and altered the microvasculature of the dentate gyrus. Thus, enhanced vulnerability of AHN to neurodegeneration might underlie hippocampal dysfunction during physiological and pathological aging in humans.Fil: Terreros Roncal, J.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Moreno Jiménez, E.P.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Flor García, M.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Rodríguez Moreno, C.B.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Trinchero, Mariela Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Cafini, F.. Universidad Europea de Madrid; EspañaFil: Rábano, A.. No especifíca;Fil: Llorens Martín, M.. Universidad Autónoma de Madrid; Españ

    Common evolutionary origin and birth-and-death process in the replication-independent histone H1 isoforms from vertebrate and invertebrate genomes

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    [Abstract]The H1 histone multigene family shows the greatest diversity of isoforms among the five histone gene families, including replication-dependent (RD) and replication-independent (RI) genes, according to their expression patterns along the cell cycle and their genomic organization. Although the molecular characterization of the RI isoforms has been well documented in vertebrates, similar information is lacking in invertebrates. In this work we provide evidence for a polyadenylation signature in the Mytilus “orphon” H1 genes similar to the polyadenylation characteristic of RI H1 genes. These mussel genes, together with the sea urchin H1δ genes, are part of a lineage of invertebrate “orphon” H1 genes that share several control elements with vertebrate RI H1 genes. These control elements include the UCE element, H1-box and H4-box. We provide evidence for a functional evolution of vertebrate and invertebrate RI H1 genes, which exhibit a clustering pattern by type instead of by species, with a marked difference from the somatic variants. In addition, these genes display an extensive silent divergence at the nucleotide level which is always significantly larger than the nonsilent. It thus appears that RI and RD H1 isoforms display similar long-term evolutionary patterns, best described by the birth-and-death model of evolution. Notably, this observation is in contrast with the theoretical belief that clustered RD H1 genes evolve in a concerted manner. The split of the RI group from the main RD group must therefore have occurred before the divergence between vertebrates and invertebrates about 815 million years ago. This was the result of the transposition of H1 genes to solitary locations in the genome.Xunta de Galicia; 10PX110304Canadá. Canadian Institutes of Health Research; MOP-5771

    Low-level laser therapy in patients with Burning Mouth Syndrome : a double-blind, randomized, controlled clinical trial

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    Evaluate the effect of LLLT in the treatment of burning mouth syndrome (BMS). Twenty-one BMS patients were randomly assigned to two groups: 12 in the laser group (LG) and 9 in the control group (CG). Patients in the LG underwent 2-week sessions of LLLT for 4 weeks. The spot tip area of this tool is 0.088cm2, semi-conductor GaAlAs, with a wavelength of 808nm ±5nm (infrared), 200 mW output power, 1.97W/cm2 of power density, 3 J energy per point and application time 15 seconds per point. LLLT was applied punctually, in continuous emissions, on each of the sites where there was a symptom. Symptoms were evaluated with a visual analogue scale (VAS) and patient psychological profiles were assessed using the Hospital Anxiety-Depression Scale. No side effects were recorded. Statistical analysis was carried out via ANOVA and logistic regression analysis. The initial VAS score mean was 8.9 for the LG and 8.3 for the CG (p >0.05). After the eighth session the VAS score was 5.5 and 5.8 respectively, and at two months it was 4.7 and 5.1 respectively. Improvement variables were established by dichotomizing the pain scales. We obtained levels of significance for the improvement variable for the LG at the two-month follow-up (p=0.0038) and for the univariate analysis of the treatment. The improvement was marginally significant in the multivariant analysis of: dry mouth, dysgeusia, pain and the treatment (p=0.0538). LLLT may be an alternative treatment for the relief of oral burning in patients with BMS
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