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961.
Pedroso DC Tellechea A Moura L Fidalgo-Carvalho I Duarte J Carvalho E Ferreira L 《PloS one》2011,6(1):e16114
In this study, we developed a methodology to improve the survival, vascular differentiation and regenerative potential of umbilical cord blood (UCB)-derived hematopoietic stem cells (CD34(+) cells), by co-culturing the stem cells in a 3D fibrin gel with CD34(+)-derived endothelial cells (ECs). ECs differentiated from CD34(+) cells appear to have superior angiogenic properties to fully differentiated ECs, such as human umbilical vein endothelial cells (HUVECs). Our results indicate that the pro-survival effect of CD34(+)-derived ECs on CD34(+) cells is mediated, at least in part, by bioactive factors released from ECs. This effect likely involves the secretion of novel cytokines, including interleukin-17 (IL-17) and interleukin-10 (IL-10), and the activation of the ERK 1/2 pathway in CD34(+) cells. We also show that the endothelial differentiation of CD34(+) cells in co-culture with CD34(+)-derived ECs is mediated by a combination of soluble and insoluble factors. The regenerative potential of this co-culture system was demonstrated in a chronic wound diabetic animal model. The co-transplantation of CD34(+) cells with CD34(+)-derived ECs improved the wound healing relatively to controls, by decreasing the inflammatory reaction and increasing the neovascularization of the wound. 相似文献
962.
Solange D. Sousa Luigi Lucini Paolo Ajmone‐Marsan Maurício F. van Tilburg Arlindo A. Moura 《Molecular reproduction and development》2020,87(4):409-418
The present study was conducted to characterize the metabolome of accessory gland fluid (AGF) of locally adapted Morada Nova rams, raised in the Brazilian Northeast. AGF was collected by an artificial vagina from five vasectomized rams. Metabolites were identified by gas chromatography‐mass spectrometry (GC/MS) and high‐performance liquid chromatography‐mass spectrometry (LC/MS), with the support of Human Metabolome Database, PubChem, LIPID Metabolites, Pathways Strategy databases, and MetaboAnalyst platforms. There were 182 and 190 metabolites detected by GC/MS and LC/MS, respectively, with an overlap of one molecule. Lipids and lipid‐like molecules were the most abundant class of metabolites in the ram AGF (127 compounds), followed by amino acids, peptides, and analogs(103 metabolites). Considering all GC/MS and LC/MS, fructose, glycerol, citric acid, d ‐mannitol, d ‐glucose, and l ‐(+)‐lactic acid were the most abundant single metabolites present in the ram AGF. Meaningful pathways associated with AGF metabolites included glycine, serine and threonine metabolism; pantothenate and CoA biosynthesis; galactose metabolism; glutamate metabolism and phenylalanine metabolism, and so forth. In conclusion, the combined use of LC/MS and GC/MS was essential for getting a holistic view of the compounds embedded in the ram AGF. Chemical analysis of the accessory sex gland secretion is relevant for understanding sperm function and fertilization. 相似文献
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Etienne Paubelle Florence Zylbersztejn Sawsaneh Alkhaeir Felipe Suarez Céline Callens Micha?l Dussiot Fran?oise Isnard Marie-Thérèse Rubio Gandhi Damaj Norbert-Claude Gorin Jean-Pierre Marolleau Renato C. Monteiro Ivan C. Moura Olivier Hermine 《PloS one》2013,8(6)
The prognosis of acute myeloid leukemia (AML) in elderly (≥65 years) patients is poor and treatment remains non-consensual especially for those who are not eligible for intensive therapies. Our group has shown that in vitro the iron chelator deferasirox (DFX) synergizes with vitamin D (VD) to promote monocyte differentiation in primary AML cells. Herein, we present results from a retrospective case-control study in which the association of DFX (1–2 g/d) and 25-hydroxycholecalciferol (100,000 IU/week) (DFX/VD) was proposed to patients following demethylating agents failure. Median survival of patients treated with DFX/VD combination (n = 17) was significantly increased in comparison with matched patients receiving best supportive care (BSC) alone (n = 13) (10.4 versus 4 months respectively). In addition, the only factor associated to an increased overall survival in DFX/VD-treated patients was serum VD levels. We conclude that DFX/VD treatment correlated with increased overall survival of AML patients in this retrospective cohort of elderly patients. 相似文献
966.
Ana Carolina Callegario Pereira Nelson Moura Brasil do Amaral Sobrinho Alfredo Tolón-Becerra Marcio Osvaldo Lima Magalhães Nelson Mazur Xavier Lastra-Bravo 《Soil & Sediment Contamination》2013,22(4):376-389
The objective of this study was to evaluate the phytostabilization of two substrates contaminated with heavy metals from excavations of the ore courtyard at the port of Itaguai, Brazil. Initially, an inventory of tree species located near the study area was performed to select species for phytostabilization. The species Cordia africana exhibited deeper roots, a larger diameter at chest height (DCH) and crown diameter, as well as higher concentrations of Zn, Cd, and Pb in the trunk, bark, and roots compared to the other investigated species. The tolerance of the selected species to the metals Zn, Cd, and Pb was subsequently assessed through a greenhouse test. The substrates used in the experiment also obtained from excavations at the ore courtyard and showed different levels of heavy metals, indicating either low contamination (Substrate 1) or high contamination (Substrate 2). Alkaline industrial waste steel slag (SS) was used as an amendment to reduce the solubility of heavy metals. Application of the amendment agent to the substrates reduced the bioavailability of heavy metals, favoring the growth of C. africana. This species presents potential for use in phytostabilization programs due to its tolerance for heavy metals and the observed higher accumulation of these metals in the roots and especially the trunk of this species compared to other vegetal parts. 相似文献
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Asopines are predators of insects, with several species with potential as biocontrol agents of a number of pests. Metrogaleruca obscura (Degeer), a neotropical species of Galerucini, was introduced in Malaysia, Asia, and Mauritius, Africa, to control the spread of Cordia curassavica (Boraginaceae), a native plant of the neotropics. The occurrence of Podisus nigrispinus (Dallas) preying on M. obscura is recorded, and Cordia verbenacea (Boraginaceae) is mentioned as a host plant for M. obscura. A list of Chrysomelidae attacked by asopines in the neotropical region is also presented. 相似文献
970.
Genetic code alterations discovered over the last 40 years in bacteria and eukaryotes invalidate the hypothesis that the code is universal and frozen. Mitochondria of various yeast species translate the UGA stop codon as tryptophan (Trp) and leucine (Leu) CUN codons (N = any nucleotide) as threonine (Thr) and fungal CTG clade species reassigned Leu CUG codons to serine and translate them ambiguously in their cytoplasms. This unique sense-to-sense genetic code alteration is mediated by a Ser-tRNA containing a Leu 5'-CAG-3'anticodon (ser-tRNA(CAG)), which is recognized and charged with Ser (~97%) by the seryl-tRNA synthetase (SerRS) and with Leu (~3%) by the leucyl-tRNA synthetase (LeuRS). This unusual tRNA appeared 272 ± 25 million years ago and had a profound impact on the evolution of the CTG clade species. Here, we review the most recent results and concepts arising from the study of this codon reassignment and we highlight how its study is changing our views of the evolution of the genetic code. 相似文献