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991.
992.
Prenatal diagnosis in two successive pregnancies revealed the karyotype 46,XX,15p+ (pat). Using the Y heterochromatic probe pHY3.4 and fluorescence in situ hybridisation, the variant 15 was identified as a t(Y;15)(q12;p11). Interphase scanning alone would have given a false result in both prenatal assessments and in the phenotypically normal father. 相似文献
993.
Robson Ferreira Cavalcante de Almeida Marcos Valério Garcia Rodrigo Casquero Cunha Jaqueline Matias Elaine Araújo e Silva Maria de Fatima Cepa Matos Renato Andreotti 《Experimental & applied acarology》2013,60(1):63-72
Ticks from 148 dogs from the urban area of the municipality of Campo Grande, state of Mato Grosso do Sul, Brazil, were collected, classified and analyzed using polymerase chain reaction (PCR) for the identification of Rickettsia spp., Trypanosoma cruzi and Leishmania spp. A total of 2015 ticks were collected. The species Rhipicephalus sanguineus (98.9 %) and Amblyomma cajennense (1.1 %) were identified. Molecular analysis revealed that no tick samples were infected by T. cruzi. Regarding Leishmania spp., tick samples from 36 dogs spread across all regions of the municipality were positive for L. chagasi. One tick sample was positive for Rickettsia spp. (gltA gene) in the PCR reaction. This sample was submitted to further PCR based on the ompA gene and the amplicon was sequenced. Identity of 100 % was found with homologous sequences of R. rickettsii available in GenBank. This paper is the first to report the natural infection of R. sanguineus by R. rickettsii in the municipality of Campo Grande, state of Mato Grosso do Sul, mid-western Brazil. 相似文献
994.
Rebeca Caldeira Machado Berger Paula Frizera Vassallo Renato de Oliveira Crajoinas Marilene Luzia Oliveira Flávia Letícia Martins Breno Valentim Nogueira Daisy Motta-Santos Isabella Binotti Araújo Ludimila Forechi Adriana Castello Costa Girardi Robson Augusto Souza Santos José Geraldo Mill 《PloS one》2015,10(10)
Several evidences have shown that salt excess is an important determinant of cardiovascular and renal derangement in hypertension. The present study aimed to investigate the renal effects of chronic high or low salt intake in the context of hypertension and to elucidate the molecular mechanisms underlying such effects. To this end, newly weaned male SHR were fed with diets only differing in NaCl content: normal salt (NS: 0.3%), low salt (LS: 0.03%), and high salt diet (HS: 3%) until 7 months of age. Analysis of renal function, morphology, and evaluation of the expression of the main molecular components involved in the renal handling of albumin, including podocyte slit-diaphragm proteins and proximal tubule endocytic receptors were performed. The relationship between diets and the balance of the renal angiotensin-converting enzyme (ACE) and ACE2 enzymes was also examined. HS produced glomerular hypertrophy and decreased ACE2 and nephrin expressions, loss of morphological integrity of the podocyte processes, and increased proteinuria, characterized by loss of albumin and high molecular weight proteins. Conversely, severe hypertension was attenuated and renal dysfunction was prevented by LS since proteinuria was much lower than in the NS SHRs. This was associated with a decrease in kidney ACE/ACE2 protein and activity ratio and increased cubilin renal expression. Taken together, these results suggest that LS attenuates hypertension progression in SHRs and preserves renal function. The mechanisms partially explaining these findings include modulation of the intrarenal ACE/ACE2 balance and the increased cubilin expression. Importantly, HS worsens hypertensive kidney injury and decreases the expression nephrin, a key component of the slit diaphragm. 相似文献
995.
996.
J. M. Bennett A. S. Kutt C. N. Johnson S. K. A. Robson 《Biodiversity and Conservation》2009,18(13):3407-3419
We examined the spatial fidelity in the pattern in species richness, abundance and composition of ants, birds, mammals and
reptiles in a Eucalyptus vegetation type in Australian tropical savanna woodland. We sampled 32 sites representing intact (uncleared) vegetation,
and three treatments of different clearing age (2, 12 and 18 years). We investigated whether each fauna taxon could act a
surrogate for pattern in the other, and whether they responded in parallel to time since clearing. Reptiles and mammals were
combined into a single group. The correlation between taxa was low for abundance (the best being between rept/mamm and ant
abundance R = 0.34) and moderate for species richness (varied from 0.36 to 0.44). Mantel tests identified a moderately strong relationship
between bird and rept/mamm composition (R = 0.48). Recent clearing (2–12 years) depleted both abundance and species richness of the vertebrate fauna, whereas ant abundance
spiked. Ant species richness was consistent over time since clearing. ANOSIM revealed that clearing age was a strong a priori
predictor of birds and rept/mamm composition (Global R = 0.48, 0.65, respectively), whereas it was not for ants (Global R = 0.20). Pair-wise comparisons suggested that for birds, rept/mamm, there was consistent changes in composition from intact
woodlands to different aged clearing. This was not the case for ants; most distinct variation in composition occurred between
treatments of increasing in clearing age (2–18 years R = 0.69, 12–18 years R = 0.65). The results of this study do not support the use of ants as a surrogate of vertebrates at a local scale in a cleared
and intact vegetation mosaic. We acknowledge that identification of universal surrogates and indicators are difficult to find,
but funding and political expediency that demand rapid solutions to conservation planning necessitate continued investigation
of the merits of using surrogate species. 相似文献
997.
998.
Bhavana Pothuri Mario M. Leitao Douglas A. Levine Agnès Viale Adam B. Olshen Crispinita Arroyo Faina Bogomolniy Narciso Olvera Oscar Lin Robert A. Soslow Mark E. Robson Kenneth Offit Richard R. Barakat Jeff Boyd 《PloS one》2010,5(4)
Background
The high mortality rate associated with epithelial ovarian carcinoma (EOC) reflects diagnosis commonly at an advanced stage, but improved early detection is hindered by uncertainty as to the histologic origin and early natural history of this malignancy.Methodology/Principal Findings
Here we report combined molecular genetic and morphologic analyses of normal human ovarian tissues and early stage cancers, from both BRCA mutation carriers and the general population, indicating that EOCs frequently arise from dysplastic precursor lesions within epithelial inclusion cysts. In pathologically normal ovaries, molecular evidence of oncogenic stress was observed specifically within epithelial inclusion cysts. To further explore potential very early events in ovarian tumorigenesis, ovarian tissues from women not known to be at high risk for ovarian cancer were subjected to laser catapult microdissection and gene expression profiling. These studies revealed a quasi-neoplastic expression signature in benign ovarian cystic inclusion epithelium compared to surface epithelium, specifically with respect to genes affecting signal transduction, cell cycle control, and mitotic spindle formation. Consistent with this gene expression profile, a significantly higher cell proliferation index (increased cell proliferation and decreased apoptosis) was observed in histopathologically normal ovarian cystic compared to surface epithelium. Furthermore, aneuploidy was frequently identified in normal ovarian cystic epithelium but not in surface epithelium.Conclusions/Significance
Together, these data indicate that EOC frequently arises in ovarian cystic inclusions, is preceded by an identifiable dysplastic precursor lesion, and that increased cell proliferation, decreased apoptosis, and aneuploidy are likely to represent very early aberrations in ovarian tumorigenesis. 相似文献999.
Structural and thermodynamic analysis of thrombin:suramin interaction in solution and crystal phases
Luis Maurício T.R. Lima Camila Franco Becker Guilherme Menegon Giesel Adriana Fonseca Marques Maria Thereza Cargnelutti Mario de Oliveira Neto Robson Queiroz Monteiro Hugo Verli Igor Polikarpov 《Biochimica et Biophysica Acta - Proteins and Proteomics》2009,1794(6):873-881
Suramin is a hexasulfonated naphthylurea which has been recently characterized as a non-competitive inhibitor of human alpha-thrombin activity over fibrinogen, although its binding site and mode of interaction with the enzyme remain elusive. Here, we determined two X-ray structure of the thrombin:suramin complex, refined at 2.4 Å resolution. While a single thrombin:suramin complex was found in the asymmetric unit cell of the crystal, some of the crystallographic contacts with symmetrically related molecules are mediated by both the enzyme and the ligand. Molecular dynamics simulations with the 1:1 complex demonstrate a large rearrangement of suramin in the complex, but with the protein scaffold and the more extensive protein–ligand regions keep unchanged. Small-angle X-ray scattering measurements at high micromolar concentration demonstrate a suramin-induced dimerization of the enzyme. These data indicating a dissimilar binding mode in the monomeric and oligomeric states, with a monomeric, 1:1 complex to be more likely to exist at the thrombin physiological, nanomolar concentration range. Collectively, close understanding on the structural basis for interaction is given which might establish a basis for design of suramin analogues targeting thrombin. 相似文献
1000.
Although CD8+ T lymphocytes are present in human decidua throughout pregnancy, albeit as a minor population in early pregnancy, their role in normal pregnancy is largely unknown. The present study aimed to characterize their effector phenotype, including cytolytic activity, cytokine profile, and capacity to affect placental invasion. CD8+ lymphocytes were positively selected from normal early pregnancy decidua (7-14 wks gestational age). Decidual CD8+ T lymphocytes were studied using standard and redirected chromium release assays to investigate natural killer cell-sensitive cytotoxicity and cytotoxicity that requires T-cell receptor signal transduction respectively, multiplex cytokine analysis to analyze cytokine production, and a placental explant invasion model to assess the effect of soluble products of decidual CD8+ T lymphocytes on trophoblast invasion. Decidual CD8+ T lymphocytes exhibited cytolytic ability against P815 target cells (mean % Specific Chromium Release at effector:target ratio of 32:1 [SCR(32)] of 32.7 +/- 5.8) and against K562 target cells (mean SCR(32) of 20.3 +/- 0.5). Phytohemagglutinin-P (PHA-P)-stimulated decidual CD8(+) T lymphocytes produced high levels of both interferon gamma and interleukin (IL) 8, and low levels of granulocyte-macrophage colony-stimulating factor (CSF2), IL1B, IL2, IL6, IL10, IL12, and tumor necrosis factor; these did not vary with gestational age. IL4 was undetectable. Decidual CD8+ T lymphocyte supernatants increased the capacity of extravillous trophoblast cells to invade through Matrigel compared with the PHA-P control. These findings suggest that decidual CD8+ T cells can display cytolytic activity, do not evoke a predominant local intrauterine Th2 type cytokine environment, and may act to regulate invasion of extravillous trophoblast cells into the uterus, a crucial process for normal uteroplacental development. 相似文献