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991.
Nitric Oxide Plays a Role in Stem Cell Niche Homeostasis through Its Interaction with Auxin 总被引:1,自引:0,他引:1
992.
The knowledge of reference ranges for hematologic, biochemical, and blood gas parameters in the different species and the influence of breed and age on them is a fundamental tool for the clinician. For this reason, the aim of this study was to evaluate the age-related changes of hematologic and biochemical parameters in Martina Franca donkey foals during the first 3 weeks of life and of blood gases during the first 24 hours of age. Fifteen healthy donkey foals were enrolled; blood samples were collected from each foal at 10 minutes after birth, 1 hour after the first and second suckles, 12 and 24 hours after birth, daily from Day 2 to 7, and at Days 10, 14, and 21 of life. Erythrocytes, leukocytes, and platelets counts were assessed; also metabolic (alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, creatinphospokinase, lactate dehydrogenase, alkaline phosphatase, glucose, blood urea nitrogen, creatinine, total proteins, albumins, cholesterol, and total bilirubin) and electrolytic parameters (Ca, P, Mg, Na, K, and Cl) were evaluated. Finally, blood gases and metabolic parameters (pH, pCO2, pO2, sO2, TCO2, HCO3, lactate, and base excess) on venous blood were assessed with a portable analyzer. A statistical analysis to evaluate the influence of age and sex was performed. Several differences were found between sampling times, demonstrating that age influences these parameters. Moreover differences were found compared with data reported in literature for donkey foals of another species, horse foals, and adult donkeys. Although a great interindividual variation for some parameters exists, this study demonstrated that interval references should be addressed not only to different species, but also to specific breeds and to the neonatal period. 相似文献
993.
Marcy R. Auerbach Donghong Yan Rajesh Vij Jo-Anne Hongo Gerald Nakamura Jean-Michel Vernes Y. Gloria Meng Samantha Lein Pamela Chan Jed Ross Richard Carano Rong Deng Nicholas Lewin-Koh Min Xu Becket Feierbach 《PLoS pathogens》2014,10(4)
Human cytomegalovirus (HCMV) is the most common cause of congenital virus infection. Congenital HCMV infection occurs in 0.2–1% of all births, and causes birth defects and developmental abnormalities, including sensorineural hearing loss and developmental delay. Several key studies have established the guinea pig as a tractable model for the study of congenital HCMV infection and have shown that polyclonal antibodies can be protective [1]–[3]. In this study, we demonstrate that an anti-guinea pig CMV (GPCMV) glycoprotein H/glycoprotein L neutralizing monoclonal antibody protects against fetal infection and loss in the guinea pig. Furthermore, we have delineated the kinetics of GPCMV congenital infection, from maternal infection (salivary glands, seroconversion, placenta) to fetal infection (fetus and amniotic fluid). Our studies support the hypothesis that a neutralizing monoclonal antibody targeting an envelope GPCMV glycoprotein can protect the fetus from infection and may shed light on the therapeutic intervention of HCMV congenital infection in humans. 相似文献
994.
López GV Batthyány C Blanco F Botti H Trostchansky A Migliaro E Radi R González M Cerecetto H Rubbo H 《Bioorganic & medicinal chemistry》2005,13(20):5787-5796
Synthesis and biological characterization of a series of alpha-tocopherol analogs with NO-releasing capacity are reported. The selected NO-donor moieties were nitrooxy and furoxan. All products were tested for their in vitro NO-releasing capacities, vasodilating properties, and antiplatelet activity. They were also capable of preventing LDL oxidation. 相似文献
995.
Amanda F. S. Mendes Chunxian Chen Fred G. Gmitter Gloria A. Moore Marcio G. C. Costa 《Physiologia plantarum》2011,141(1):1-10
Two new lycopene β‐cyclases (LCYBs) were cloned and characterized from grapefruit (Citrus paradisi Macf.). During fruit ripening, CpLCYB1 expression did not show significant differences between ‘Flame’ (red flesh) and ‘Marsh’ (white flesh), and was much lower than CpLCYB2 and nearly constant; however, CpLCYB2 expression dramatically changed in a similar tendency in the pulp of both grapefruit cultivars, but the relative abundance of mRNA in ‘Flame’ was significantly lower than in ‘Marsh’. Phylogenetically and structurally, CpLCYB1 was a chloroplast‐specific member and CpLCYB2 a chromoplast‐specific member, the two subfamilies of all the LCYB genes. An intron was found in the 5′‐untranslated region of CpLCYB1 and in two other Citrus LCYB1 genes (CcLCYB1 and CsLCYB1‐2), resulting in an extra 20 amino acids, compared with all the other LCYB1s. It suggested that a different genomic event, in addition to gene duplication, has contributed to the evolution of these LCYB genes, and likewise, the change of their functions. 相似文献
996.
Blain HA Bailon S Cuenca-Bescós G Arsuaga JL Bermúdez de Castro JM Carbonell E 《Journal of human evolution》2009,56(1):55-37
The Gran Dolina cave site is famous for having delivered some of the oldest hominin remains of Western Europe (Homo antecessor, ca. 960 ka). Moreover, the evidence of lithic industries throughout the long vertical section suggests occupation on the part of hominins from the latest early Pleistocene (levels TD3/4, TD5, and TD6) to the late middle Pleistocene (level TD10). The Gran Dolina Sondeo Sur (TDS) has furnished a great number of small-vertebrate remains; among them some 40,000 bones are attributed to amphibians and squamates. Although they do not differ specifically from the extant herpetofauna of the Iberian Peninsula, the overlap of their current distribution areas (= mutual climatic range method) in Spain can provide mean annual temperatures (MAT), the mean temperatures of the coldest (MTC) and warmest (MTW) months, and mean annual precipitation (MAP) estimations for each sub-level, and their change can be studied throughout the sequence. Results from the squamate and amphibian study indicate that during hominin occupation the MAT (10-13 °C) was always slightly warmer than at present in the vicinity of the Gran Dolina Cave, and the MAP (800-1000 mm) was greater than today in the Burgos area. Climatic differences between “glacial” and “interglacial” phases are poorly marked. Summer temperatures (MTW) show stronger oscillations than winter temperatures (MTC), but seasonality remains almost unchanged throughout the sequence. These results are compared with those for large mammals, small mammals, and pollen analysis, giving a scenario for the palaeoclimatic conditions that occurred during the early to middle Pleistocene in Atapuerca, and hence a scenario for the hominins that once lived in the Sierra de Atapuerca. 相似文献
997.
Guang-dan Zhu Gloria Salazar Stephanie A. Zlatic Babar Fiza Michele M. Doucette Craig J. Heilman Allan I. Levey Victor Faundez Steven W. L'Hernault 《Molecular biology of the cell》2009,20(4):1223-1240
Yeast and animal homotypic fusion and vacuole protein sorting (HOPS) complexes contain conserved subunits, but HOPS-mediated traffic in animals might require additional proteins. Here, we demonstrate that SPE-39 homologues, which are found only in animals, are present in RAB5-, RAB7-, and RAB11-positive endosomes where they play a conserved role in lysosomal delivery and probably function via their interaction with the core HOPS complex. Although Caenorhabditis elegans spe-39 mutants were initially identified as having abnormal vesicular biogenesis during spermatogenesis, we show that these mutants also have disrupted processing of endocytosed proteins in oocytes and coelomocytes. C. elegans SPE-39 interacts in vitro with both VPS33A and VPS33B, whereas RNA interference of VPS33B causes spe-39–like spermatogenesis defects. The human SPE-39 orthologue C14orf133 also interacts with VPS33 homologues and both coimmunoprecipitates and cosediments with other HOPS subunits. SPE-39 knockdown in cultured human cells altered the morphology of syntaxin 7-, syntaxin 8-, and syntaxin 13-positive endosomes. These effects occurred concomitantly with delayed mannose 6-phosphate receptor-mediated cathepsin D delivery and degradation of internalized epidermal growth factor receptors. Our findings establish that SPE-39 proteins are a previously unrecognized regulator of lysosomal delivery and that C. elegans spermatogenesis is an experimental system useful for identifying conserved regulators of metazoan lysosomal biogenesis. 相似文献
998.
999.
Stephanie A. Zlatic Pearl V. Ryder Gloria Salazar Victor Faundez 《Journal of visualized experiments : JoVE》2010,(37)
The dynamic nature of cellular machineries is frequently built on transient and/or weak protein associations. These low affinity interactions preclude stringent methods for the isolation and identification of protein networks around a protein of interest. The use of chemical crosslinkers allows the selective stabilization of labile interactions, thus bypassing biochemical limitations for purification. Here we present a protocol amenable for cells in culture that uses a homobifunctional crosslinker with a spacer arm of 12 Å, dithiobis-(succinimidyl proprionate) (DSP). DSP is cleaved by reduction of a disulphide bond present in the molecule. Cross-linking combined with immunoaffinity chromatography of proteins of interest with magnetic beads allows the isolation of protein complexes that otherwise would not withstand purification. This protocol is compatible with regular western blot techniques and it can be scaled up for protein identification by mass spectrometry1.Stephanie A. Zlatic and Pearl V. Ryder contributed equally to this work.Open in a separate windowClick here to view.(62M, flv) 相似文献
1000.