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The rate of seven meiotic stages (zygotene-pachytene, diplotene-diakinesis, metaphase I, anaphase I, metaphase II, anaphase II, and quartet) was studied in the jerboas Jaculus jaculus jaculus, Jaculus orientalis, and Allactaga tetradactyla, chiasma frequency and terminalization being examined only in J. jaculus and J. orientalis, and compared with the previous data concerning A. tetradactyla. Significant differences in the rate of meiosis, frequency of bivalent types, and frequency of interstitial and distal or terminal chiasmata per genome length were observed between A. tetradactyla and the two congeneric species J. jaculus and J. orientalis. Differences of these parameters among individuals within each species are also discussed in detail. 相似文献
73.
Caksen H Tuncer O Ataş B Demirok A Unal O Ikbal M Odabaş D 《Genetic counseling (Geneva, Switzerland)》2003,14(3):343-348
The patient is a 12-year-old boy with a history of learning disability, growth retardation, and strabismus. Weight, height and head circumference were below the 3rd percentile. A café-au-lait spot, 1x1 cm a diameter, on the back region and pectus excavatum deformity were diagnosed. He had facial asymmetry, a broad nose, sparse eyebrows and eyelashes, a rudimentary frontal sinus, deviation of the nasal septum, and bilateral small maxillary bones. The left orbital fossa was also mildly rudimentary. On eye examination the movements of the left globe to the upward and lateral side were limited and internal strabismus was noted at this side. Visual acuity was 1/10, bilaterally. Bilateral choroid coloboma, glaucoma, vertical and horizontal nystagmus were diagnosed. Fundoscopic examination revealed bilateral optic atrophy and macular and paramacular granulation tissues on the left side. Intelligence quotient was 46. Electroencephalography revealed bilateral frontal slow-wave activity. Visual evoked potential revealed prolonged p100 wave latencies bilaterally. Magnetic resonance imaging of the brain demonstrated corpus callosum dysgenesis, bilateral subcortical heterotopia in the frontal lobes and subependymal heterotopia in the posterior horn of the left ventricle. Chromosomal analysis revealed a normal male karyotype, 46, XY. Although several cases of heterotopia in association with mental retardation, craniofacial dysmorphism, cerebral, and eye abnormalities have been described the combination of abnormalities diagnosed in our case has not previously been reported. We hypothesize that the combination of subcortical/subependymal heterotopia, corpus callosum dysgenesis, craniofacial dysmorphism, severe eye abnormalities, and growth-mental retardation may be a new syndrome. 相似文献
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Ana Sofia Duque Susana de Sousa Araújo Matilde Ataíde Cordeiro Dulce Maria Santos Manuel Pedro Fevereiro 《Plant Cell, Tissue and Organ Culture》2007,90(3):325-330
We developed an alternative methodology for in vitro selection of transgenic Medicago truncatula cv. Jemalong plants using a bifunctional construct in which the coding sequences for the green fluorescent protein (GFP)
and the β-glucuronidase protein (GUS) are fused. An Agrobacterium-mediated transformation protocol was used followed by regeneration via somatic embryogenesis in the dark, to avoid the synthesis and the consequent autofluorescence of chlorophyll. This method
is a clear advantage over antibiotic and herbicide selection in which survival of non-transformed tissue is commonly reported,
with the reassurance that all the somatic embryos selected as GFP positive are transformed. This was subsequently corroborated
by the detection of GUS activity in leaves, stems and roots of the regenerated plants. Without antibiotic selection, and performing
the embryo induction in the dark, it was possible to attest the advantage of using GFP as an in vivo detectable reporter for
early embryo selection. The fusion with the GUS coding sequence provided additional evidence for the transformation of the
previously selected embryos. 相似文献
76.
Coutinho AM Sousa I Martins M Correia C Morgadinho T Bento C Marques C Ataíde A Miguel TS Moore JH Oliveira G Vicente AM 《Human genetics》2007,121(2):243-256
Autism is a neurodevelopmental disorder of unclear etiology. The consistent finding of platelet hyperserotonemia in a proportion
of patients and its heritability within affected families suggest that genes involved in the serotonin system play a role
in this disorder. The role in autism etiology of seven candidate genes in the serotonin metabolic and neurotransmission pathways
and mapping to autism linkage regions (SLC6A4, HTR1A, HTR1D, HTR2A, HTR5A, TPH1 and ITGB3) was analyzed in a sample of 186 nuclear families. The impact of interactions among these genes in autism was assessed using
the multifactor-dimensionality reduction (MDR) method in 186 patients and 181 controls. We further evaluated whether the effect
of specific gene variants or gene interactions associated with autism etiology might be mediated by their influence on serotonin
levels, using the quantitative transmission disequilibrium test (QTDT) and the restricted partition method (RPM), in a sample
of 109 autistic children. We report a significant main effect of the HTR5A gene in autism (P = 0.0088), and a significant three-locus model comprising a synergistic interaction between the ITGB3 and SLC6A4 genes with an additive effect of HTR5A (P < 0.0010). In addition to the previously reported contribution of SLC6A4, we found significant associations of ITGB3 haplotypes with serotonin level distribution (P = 0.0163). The most significant models contributing to serotonin distribution were found for interactions between TPH1 rs4537731 and SLC6A4 haplotypes (P = 0.002) and between HTR1D rs6300 and SLC6A4 haplotypes (P = 0.013). In addition to the significant independent effects, evidence for interaction between SLC6A4 and ITGB3 markers was also found. The overall results implicate SLC6A4 and ITGB3 gene interactions in autism etiology and in serotonin level determination, providing evidence for a common underlying genetic
mechanism and a molecular explanation for the association of platelet hyperserotonemia with autism.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Gomes AB Soares KA Bueno EC Espindola NM Iha AH Maia AA Peralta RH Vaz AJ 《Memórias do Instituto Oswaldo Cruz》2007,102(6):725-731
Seven swine were experimentally infected with Taenia solium eggs and blood samples from each animal were periodically collected. At the end of the experiment (t140) the animals did not show clinical aspects of cysticercosis or parasites in tongue inspection. All animals were slaughtered and cut into thin slices in searching for cysts. The number of cysts found in each animal varied from 1 to 85. Enzyme-linked immunosorbent assay (ELISA) tests for antibody (Ab) detection and for antigen (Ag) detection were performed, which presented respectively 71 and 57% of positivity. By immunoblot (IB), using 18/14(T. crassiceps Ag) or lentil-lectin-purified glycoproteins from T. solium Ag (LLGP) as Ag, five (71%) and six (86%) animals were positive, respectively. The association between Ag-ELISA with any IB (18/14 or LLGP) allowed the detection of all animals at 140 days post-experimental infection (days p.e.i.). The use of IB 18/14 combined to the Ag-ELISA allowed the detection of all animals since 70 days p.e.i., and the association between IB LLGP and Ag-ELISA allowed the detection of all animals since 112 days p.e.i. While all animals could be considered healthy by conventional screening tests, the use of immunoassays for detecting Ab and Ag showed better accuracy; therefore it would be more useful than usual clinical examination for screening cysticercosis in slightly infected pigs. 相似文献
80.
Ricardo Ataíde Oscar Murillo Jamille G. Dombrowski Rodrigo M. Souza Flávia A. Lima Giselle F. M. C. Lima Angélica D. Hristov Suiane C. N. Valle Silvia M. Di Santi Sabrina Epiphanio Claudio R. F. Marinho 《PLoS neglected tropical diseases》2015,9(6)
Malaria in pregnancy remains a substantial public health problem in malaria-endemic areas with detrimental outcomes for both the mother and the foetus. The placental changes that lead to some of these detrimental outcomes have been studied, but the mechanisms that lead to these changes are still not fully elucidated. There is some indication that imbalances in cytokine cascades, complement activation and angiogenic dysregulation might be involved in the placental changes observed. Nevertheless, the majority of studies on malaria in pregnancy (MiP) have come from areas where malaria transmission is high and usually restricted to Plasmodium falciparum, the most pathogenic of the malaria parasite species. We conducted a cross-sectional study in Cruzeiro do Sul, Acre state, Brazil, an area of low transmission and where both P. vivax and P. falciparum circulate. We collected peripheral and placental blood and placental biopsies, at delivery from 137 primigravid women and measured levels of the angiogenic factors angiopoietin (Ang)-1, Ang-2, their receptor Tie-2, and several cytokines and chemokines. We measured 4 placental parameters (placental weight, syncytial knots, placental barrier thickness and mononuclear cells) and associated these with the levels of angiogenic factors and cytokines. In this study, MiP was not associated with severe outcomes. An increased ratio of peripheral Tie-2:Ang-1 was associated with the occurrence of MiP. Both Ang-1 and Ang-2 had similar magnitudes but inverse associations with placental barrier thickness. Malaria in pregnancy is an effect modifier of the association between Ang-1 and placental barrier thickness. 相似文献