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61.
Saccharomyces cerevisiae CGR1 encodes a 120-amino acid protein with a predominant nucleolar localization. In this study we report the identification and
cloning of the ortholog, cgrA, from Aspergillus nidulans. The cgrA gene is comprised of three exons on A. nidulans Chromosome 7. The cDNA contains a single open reading frame (ORF) that would encode a protein of 114 amino acids with 44%
sequence identity to yeast Cgr1p. A plasmid expressing cgrA complemented the impaired growth phenotype of a yeast strain that can be inducibly depleted of CGR1, and a green fluorescent protein (GFP)-tagged CgrA protein had the same nucleolar localization as the corresponding yeast
protein. These results identify cgrA as the A. nidulans ortholog of yeast CGR1 and suggest evolutionary conservation of nucleolar localization mechanisms used by these proteins.
Received: 14 September 2000 / Accepted: 13 November 2000 相似文献
62.
We formulate a non-linear system of differential equations that models the dynamics of transmission of dengue fever. We consider vertical and mechanical transmission in the vector population, and study the effects that they have on the dynamics of the disease. A qualitative analysis as well as some numerical examples are given for the model. 相似文献
63.
Nancy Argüelles Eugenia Sánchez-Sandoval Aarón Mendieta Lourdes Villa-Tanaca Leticia Garduño-Siciliano Fabiola Jiménez María del Carmen Cruz José L. Medina-Franco Germán Chamorro-Cevallos Joaquín Tamariz 《Bioorganic & medicinal chemistry》2010,18(12):4238-4248
A series of α-asarone-based analogues was designed by conducting docking experiments with published crystal structures of human HMG-CoA reductase. Indeed, synthesis and evaluation of this series showed a highly hypocholesterolemic in vivo activity in a murine model, as predicted by previous docking studies. In agreement with this model, the polar groups attached to the benzene ring could play a key role in the enzyme binding and probably also in its biological activity, mimicking the HMG-moiety of the natural substrate. The hypolipidemic action mechanism of these compounds was investigated by developing a simple, efficient, and novel model for determining HMG-CoA reductase inhibition. The partial purification of the enzyme from Schizosaccharomyces pombe allowed for testing of α-asarone- and fibrate-based analogues, resulting in positive and significant inhibitory activity. 相似文献
64.
José A. López-Sáez Lourdes López-Merino Miguel Á. Mateo Óscar Serrano Sebastián Pérez-Díaz Laura Serrano 《Palaeogeography, Palaeoclimatology, Palaeoecology》2009,271(3-4):215-224
A high-resolution sedimentary sequence sampled from the Portlligat Bay (NE Iberian Peninsula) has been studied in order to assess its palaeoecological potential. This sedimentary sequence is considered a very particular one, as it is a peat-like deposit derived from the accumulation of the belowground dead parts of the marine phanerogam Posidonia oceanica through the last 1600 years. This study represents the first attempt to explore the palaeoecological potential of such deposits from a palynological point of view, and has allowed the reconstruction of the vegetation dynamics and changes, human impact and the palaeoclimatic characteristics, demonstrating the value of these sedimentary records in palaeopalynological studies. 相似文献
65.
An empirically based alternative to DSM-5's disruptive mood dysregulation disorder for ICD-11 下载免费PDF全文
66.
67.
Luiza Helena Urso Pitassi Pedro Paulo Vissotto de Paiva Diniz Diana Gerardi Scorpio Marina Rovani Drummond Bruno Grosselli Lania Maria Lourdes Barjas-Castro Rovilson Gilioli Silvia Colombo Stanley Sowy Edward B. Breitschwerdt William L. Nicholson Paulo Eduardo Neves Ferreira Velho 《PLoS neglected tropical diseases》2015,9(1)
Bartonella species are blood-borne, re-emerging organisms, capable of causing prolonged infection with diverse disease manifestations, from asymptomatic bacteremia to chronic debilitating disease and death. This pathogen can survive for over a month in stored blood. However, its prevalence among blood donors is unknown, and screening of blood supplies for this pathogen is not routinely performed. We investigated Bartonella spp. prevalence in 500 blood donors from Campinas, Brazil, based on a cross-sectional design. Blood samples were inoculated into an enrichment liquid growth medium and sub-inoculated onto blood agar. Liquid culture samples and Gram-negative isolates were tested using a genus specific ITS PCR with amplicons sequenced for species identification. Bartonella henselae and Bartonella quintana antibodies were assayed by indirect immunofluorescence. B. henselae was isolated from six donors (1.2%). Sixteen donors (3.2%) were Bartonella-PCR positive after culture in liquid or on solid media, with 15 donors infected with B. henselae and one donor infected with Bartonella clarridgeiae. Antibodies against B. henselae or B. quintana were found in 16% and 32% of 500 blood donors, respectively. Serology was not associated with infection, with only three of 16 Bartonella-infected subjects seropositive for B. henselae or B. quintana. Bartonella DNA was present in the bloodstream of approximately one out of 30 donors from a major blood bank in South America. Negative serology does not rule out Bartonella spp. infection in healthy subjects. Using a combination of liquid and solid cultures, PCR, and DNA sequencing, this study documents for the first time that Bartonella spp. bacteremia occurs in asymptomatic blood donors. Our findings support further evaluation of Bartonella spp. transmission which can occur through blood transfusions. 相似文献
68.
There is a need to know whether callous-unemotional (CU) traits identify a more severe group of oppositional defiant children (ODD). The aim of this study is to ascertain cross-sectionally and longitudinally the specific contribution of CU levels and the presence of ODD in the psychological state of preschool children from the general population. A total of 622 children were assessed longitudinally at ages 3 and 5 with a semi-structured diagnostic interview and questionnaires filled out by parents and teachers. In multivariate models simultaneously including ODD diagnosis and CU levels, controlling by socioeconomic status, ethnicity, sex, severity of conduct disorder symptoms and other comorbidity, high CU scores were related to higher levels of aggression, withdrawn, externalizing and global symptomatology, functional impairment and higher probability of comorbid disorders and use of services. The contribution of CU traits on children’s psychological state was not moderated by the presence/absence of ODD. Stability for CU traits and number of ODD-symptoms between ages 3 and 5 was statistically significant but moderate-low (intra-class correlation under .40). Assessment and identification of CU traits from preschool might help to identify a subset of children who could have socialization problems, not only among those with ODD but also among those without a diagnosis of conduct problems. 相似文献
69.
Sílvia Saumell Francesc Solé Leonor Arenillas Julia Montoro David Valcárcel Carme Pedro Carmen Sanzo Elisa Lu?o Teresa Giménez Montserrat Arnan Helena Pomares Raquel De Paz Beatriz Arrizabalaga Andrés Jerez Ana B. Martínez Judith Sánchez-Castro Juan D. Rodríguez-Gambarte José M. Raya Eduardo Ríos María Rodríguez-Rivera Blanca Espinet Lourdes Florensa 《PloS one》2015,10(6)
Isolated trisomy 8 is not considered presumptive evidence of myelodysplastic syndrome (MDS) in cases without minimal morphological criteria. One reason given is that trisomy 8 (+8) can be found as a constitutional mosaicism (cT8M). We tried to clarify the incidence of cT8M in myeloid neoplasms, specifically in MDS, and the diagnostic value of isolated +8 in MDS. Twenty-two MDS and 10 other myeloid neoplasms carrying +8 were studied. Trisomy 8 was determined in peripheral blood by conventional cytogenetics (CC) and on granulocytes, CD3+ lymphocytes and oral mucosa cells by fluorescence in situ hybridization (FISH). In peripheral blood CC, +8 was seen in 4/32 patients. By FISH, only one patient with chronic myelomonocytic leukemia showed +8 in all cell samples and was interpreted as a cT8M. In our series +8 was acquired in all MDS. Probably, once discarded cT8M by FISH from CD3+ lymphocytes and non-hematological cells, +8 should be considered with enough evidence to MDS. 相似文献
70.
Jose Manuel Trujillo Gómez Laura Díaz-Gete Carlos Martín-Cantera Mireia Fábregas Escurriola Maribel Lozano Moreno Raquel Burón Leandro Ana María Gomez Quintero Jose Luis Ballve María Lourdes Clemente Jiménez Elisa Puigdomènech Puig Ramón Casas More Beatriz Garcia Rueda Marc Casajuana Marga Méndez-Aguirre David Garcia Bonias Soraya Fernández Maestre Jessica Sánchez Fondevila 《PloS one》2015,10(9)