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41.
Juliana C. Ferreira Guaraciaba O. Ferrari Katia R. Neves Raquel T. Cavallari Wagner V. Dominguez Luciene M. dos Reis Fabiana G. Graciolli Elizabeth C. Oliveira Shiguang Liu Yves Sabbagh Vanda Jorgetti Susan Schiavi Rosa M. A. Moysés 《PloS one》2013,8(11)
High phosphate intake is known to aggravate renal osteodystrophy along various pathogenetic pathways. Recent studies have raised the possibility that dysregulation of the osteocyte Wnt/β-catenin signaling pathway is also involved in chronic kidney disease (CKD)-related bone disease. We investigated the role of dietary phosphate and its possible interaction with this pathway in an experimental model of adynamic bone disease (ABD) in association with CKD and hypoparathyroidism. Partial nephrectomy (Nx) and total parathyroidectomy (PTx) were performed in male Wistar rats. Control rats with normal kidney and parathyroid function underwent sham operations. Rats were divided into three groups and underwent pair-feeding for 8 weeks with diets containing either 0.6% or 1.2% phosphate: sham 0.6%, Nx+PTx 0.6%, and Nx+PTx 1.2%. In the two Nx+PTx groups, serum creatinine increased and blood ionized calcium decreased compared with sham control group. They also presented hyperphosphatemia and reduced serum parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) levels. Fractional urinary excretion of phosphate increased in Nx+PTx 1.2% rats despite lower PTH and FGF23 levels than in sham group. These biochemical changes were accompanied by a decrease in bone formation rates. The Nx+PTx 1.2% group had lower bone volume (BV/TV), higher osteoblast and osteocyte apoptosis, and higher SOST and Dickkopf-1 gene expression than the Nx+PTx 0.6% group. Nx+PTx 0.6% rat had very low serum sclerostin levels, and Nx+PTx 1.2% had intermediate sclerostin levels compared with sham group. Finally, there was a negative correlation between BV/TV and serum sclerostin. These results suggest that high dietary phosphate intake decreases bone volume in an experimental model of CKD-ABD, possibly via changes in SOST expression through a PTH-independent mechanism. These findings could have relevance for the clinical setting of CKD-ABD in patients who low turnover bone disease might be attenuated by optimal control of phosphate intake and/or absorption. 相似文献
42.
Renato Borges Tesser Pedro Luiz Andrade Scherholz Luciene do Nascimento Sima Godosevicius Katz 《Histochemistry and cell biology》2010,134(1):83-92
The role of differentiated trophoblast glycogen cells (GCs) in the ectoplacental cone (EPC) has not been elucidated yet. Recently,
GC progenitors have been shown to be present from embryonic day 7.5 (E7.5), but glycogen is found in GC only from E10.5. Herein,
we investigated the origin, localization and characterization of mouse GCs in EPC and their relationship with blood cells
and trophoblast giant cells (TGCs) during placentation. Implantation sites (E5.5–E12.5) were processed for histological studies,
histochemical detection (glycogen) and immunohistochemical staining (Ki67). Three-dimensional reconstruction of the EPC was
obtained from suitably oriented embryos at E7.5. Our findings evidence that GCs are present and assembled in clusters from
E6.5 to E12.5, and that they exhibit the classic vacuolated appearance and contain PAS-positive glycogen, which is amylase-sensitive
and acetylation-resistant. In fact, only GCs were stained after acetylation, confirming unequivocally their presence in tissues.
At E6.5, GCs showed numerous mitoses and vacuoles with scattered glycogen particles. At E7.5, GCs showed low numbers of mitoses
and abundant vacuoles full of glycogen. During E7.5–E8.5, GCs were in close proximity to TGCs, and cells were intercalated
by thin maternal blood spaces; placental GCs lost maternal blood contact during E9.5–E12.5. Our results indicate that GCs
are originated and proliferate in the upper portion in the midregion of EPC at E6.5, and that at E7.5–E8.5 they show consistent
glycogen deposits, which are likely metabolized to glucose. This compound may be directly transferred to circulating maternal
blood, and used as a source of energy by GCs and TGCs during placentation. 相似文献
43.
Felipe Souto Araújo Luciene Melo Coelho Lívia do Carmo Silva Benedito Rodrigues da Silva Neto Juliana Alves Parente-Rocha Alexandre Melo Bail?o Cecília Maria Alves de Oliveira Gabriel da Rocha Fernandes Orville Hernández Juan Guillermo McEwen Ochoa Célia Maria de Almeida Soares Maristela Pereira 《PLoS neglected tropical diseases》2016,10(1)
44.
dos Santos AP Fracasso CM Luciene dos Santos M Romero R Sazima M Oliveira PE 《Annals of botany》2012,110(3):667-679
Background and Aims
Floral variation, pollination biology and mating patterns were investigated in sunbird-pollinated Babiana (Iridaceae) species endemic to the Western Cape of South Africa. The group includes several taxa with specialized bird perches and it has been proposed that these function to promote cross-pollination.Methods
Pollinator observations were conducted in 12 populations of five taxa (B. ringens subspp. ringens, australis, B. hirsuta, B. avicularis, B. carminea) and geographic variation in morphological traits investigated in the widespread B. ringens. Experimental pollinations were used to determine the compatibility status, facility for autonomous self-pollination and intensity of pollen limitation in six populations of four taxa. Allozyme markers were employed to investigate mating patterns in four populations of three species.Key Results
Sunbirds were the primary pollinators of the five Babiana taxa investigated. Correlated geographical variation in perch size, flower size and stigma–anther separation was evident among B. ringens populations. Experimental pollinations demonstrated that B. ringens and B. avicularis were self-compatible with variation in levels of autonomous self-pollination and weak or no pollen limitation of seed set. In contrast, B. hirsuta was self-incompatible and chronically pollen limited. Estimates of outcrossing rate indicated mixed mating with substantial self-fertilization in all species investigated.Conclusions
Despite the possession of specialized bird perches in B. ringens and B. avicularis, these structures do not prevent considerable selfing from occurring, probably as a result of autonomous self-pollination. In eastern populations of B. ringens, smaller flowers and reduced herkogamy appear to be associated with a shift to predominant selfing. Relaxed selection on perch function due to increased selfing may explain the increased incidence of apical flowers in some populations. 相似文献45.
Cancela AL Santos RD Titan SM Goldenstein PT Rochitte CE Lemos PA dos Reis LM Graciolli FG Jorgetti V Moysés RM 《PloS one》2012,7(5):e36883
High serum phosphorus levels have been associated with mortality and cardiovascular events in patients with chronic kidney disease and in the general population. In addition, high phosphorus levels have been shown to induce vascular calcification and endothelial dysfunction in vitro. The aim of this study was to evaluate the relation of phosphorus and coronary calcification and atherosclerosis in the setting of normal renal function. This was a cross-sectional study involving 290 patients with suspected coronary artery disease and undergoing elective coronary angiography, with a creatinine clearance >60 ml/min/1.73 m(2). Coronary artery obstruction was assessed by the Friesinger score and coronary artery calcification by multislice computed tomography. Serum phosphorus was higher in patients with an Agatston score >10 than in those with an Agatston score ≤ 10 (3.63 ± 0.55 versus 3.49 ± 0.52 mg/dl; p = 0.02). In the patients with Friesinger scores >4, serum phosphorus was higher (3.6 ± 0.5 versus 3.5 ± 0.6 mg/dl, p = 0.04) and median intact fibroblast growth factor 23 was lower (40.3 pg/ml versus 45.7 pg/ml, p = 0.01). Each 0.1-mg/dl higher serum phosphate was associated with a 7.4% higher odds of having a Friesinger score >4 (p = 0.03) and a 6.1% greater risk of having an Agatston score >10 (p = 0.01). Fibroblast growth factor 23 was a negative predictor of Friesinger score (p = 0.002). In conclusion, phosphorus is positively associated with coronary artery calcification and obstruction in patients with suspected coronary artery disease and preserved renal function. 相似文献
46.
Didelphis albiventris is a well-known and common marsupial. Due to its high adaptability, this very widespread generalist species occurs under various environmental conditions, this even including protected regions and disturbed urban areas. We studied a 653 bp fragment of cytochrome oxidase c (COI) from 93 biological samples from seven Brazilian localities, with linear distances ranging between 58 and about 1800 km to analyze the effects of geographic distances on variability and genetic differentiation. The haplotype network presented nine haplotypes and two genetic clusters compatible with the two most distant geographic areas of the states of Minas Gerais, in the southeast, and Rio Grande do Sul, in the extreme south. As each cluster was characterized by low nucleotide and high haplotype diversities, their populations were obviously composed of closely related haplotypes. Surprisingly, moderate to high F(ST) differentiation values and a very weak phylogeographic signal characterizes interpopulation comparisons within Minas Gerais interdemes, these being correlated with the presence of privative haplotypes. On a large rgeographic scale, a comparison between demes from Minas Gerais and Rio Grande do Sul presented high F(ST) values and a robust phylogeographic pattern. This unexpected scenario implies that mtDNA gene flow was insufficient to maintain population cohesion, reflected by the observed high differentiation. 相似文献
47.
Pratt-Riccio LR Bianco C Totino PR Perce-Da-Silva Dde S Silva LA Riccio EK Ennes-Vidal V Neves-Ferreira AG Perales J Da Rocha SL Dias-Da-Silva F Ferreira-da-Cruz Mde F Daniel-Ribeiro CT De Oliveira-Ferreira J Theisen M Carvalho LJ Banic DM 《Memórias do Instituto Oswaldo Cruz》2011,106(Z1):34-43
The glutamate-rich protein (GLURP) is an exoantigen expressed in all stages of the Plasmodium falciparum life cycle in humans. Anti-GLURP antibodies can inhibit parasite growth in the presence of monocytes via antibody-dependent cellular inhibition (ADCI), and a major parasite-inhibitory region has been found in the N-terminal R0 region of the protein. Herein, we describe the antiplasmodial activity of anti-GLURP antibodies present in the sera from individuals naturally exposed to malaria in a Brazilian malaria-endemic area. The anti-R0 antibodies showed a potent inhibitory effect on the growth of P. falciparum in vitro, both in the presence (ADCI) and absence (GI) of monocytes. The inhibitory effect on parasite growth was comparable to the effect of IgGs purified from pooled sera from hyperimmune African individuals. Interestingly, in the ADCI test, higher levels of tumour necrosis factor alpha (TNF-α) were observed in the supernatant from cultures with higher parasitemias. Our data suggest that the antibody response induced by GLURP-R0 in naturally exposed individuals may have an important role in controlling parasitemia because these antibodies are able to inhibit the in vitro growth of P. falciparum with or without the cooperation from monocytes. Our results also indicate that TNF-α may not be relevant for the inhibitory effect on P. falciparum in vitro growth. 相似文献
48.
49.
Luciana R. Garzoni Maria Isabel D. Rossi Virgínia Guarani Luciene B.L. Balottin Daniel Adesse Pedro Paulo Manso Maria de Nazareth Meirelles 《Experimental cell research》2009,315(19):3406-17
In embryogenesis, coronary blood vessels are formed by vasculogenesis from epicardium-derived progenitors. Subsequently, growing or regenerating myocardium increases its vasculature by angiogenesis, forming new vessels from the pre-existing ones. Recently, cell therapies for myocardium ischemia that used different protocols have given promising results, using either extra-cardiac blood vessel cell progenitors or stimulating the cardiac angiogenesis. We have questioned whether cardiomyocytes could sustain both vasculogenesis and angiogenesis. We used a 3D culture model of tissue-like spheroids in co-cultures of cardiomyocytes supplemented either with endothelial cells or with bone marrow-derived mesenchymal stroma cells. Murine foetal cardiomyocytes introduced into non-adherent U-wells formed 3D contractile structures. They were coupled by gap junctions. Cardiomyocytes segregated inside the 3D structure into clumps separated by connective tissue septa, rich in fibronectin. Three vascular endothelial growth factor isoforms were produced (VEGF 120, 164 and 188). When co-cultured with human umbilical cord endothelial cells, vascular structures were produced in fibronectin-rich external layer and in radial septa, followed by angiogenic sprouting into the cardiomyocyte microtissue. Presence of vascular structures led to the maintenance of long-term survival and contractile capacity of cardiac microtissues. Conversely, bone marrow mesenchymal cells formed isolated cell aggregates, which progressively expressed the endothelial markers von Willebrand's antigen and CD31. They proceeded to typical vasculogenesis forming new blood vessels organised in radial pattern. Our results indicate that the in vitro 3D model of cardiomyocyte spheroids provides the two basic elements for formation of new blood vessels: fibronectin and VEGF. Within the myocardial environment, endothelial and mesenchymal cells can proceed to formation of new blood vessels either through angiogenesis or vasculogenesis, respectively. 相似文献
50.
André Luís Branco de Barros Luciene das Graças Mota Carolina de Aguiar Ferreira Mônica Cristina de Oliveira Alfredo Miranda de Góes Valbert Nascimento Cardoso 《Bioorganic & medicinal chemistry letters》2010,20(21):6182-6184
A bombesin derivative was successfully radiolabeled in high labeling yield. Biodistribution studies and scintigraphic images in Ehrlich tumor-bearing mice were performed. This compound showed high accumulation in tumor tissue with high tumor-to-muscle and tumor-to-blood ratios. Thus, 99mTc-HYNIC-Bombesin(7–14) could be used as an agent for tumor diagnosis. 相似文献