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A Martínez Seeber S B Vila O L Catanzaro 《Archives internationales de physiologie et de biochimie》1985,93(2):83-88
The purpose of this study was to investigate the effect of norepinephrine and vasopressin on urinary kallikrein excretion in the rat. Two studies were undertaken: (a) acute experiments in which the rats were infused with 30% dextrose in water with the addition of norepinephrine or vasopressin, (b) chronic experiments in which the drugs were infused during seven days through an osmotic minipump. In acute experiments, urinary kallikrein excretion increased without modification in urinary flow and glomerular filtration rate. In chronic experiments, urinary kallikrein excretion was not modified in norepinephrine-treated rats and decreased in vasopressin-infused animals. This decrease followed the modifications of the urine flow. In chronic experiments the dextrose infusion increased urinary kallikrein excretion. In all the groups studied a positive correlation between urine flow and urinary kallikrein excretion was observed. It is concluded that norepinephrine and vasopressin are important stimulators of the urinary kallikrein excretion only in those circumstances where it is necessary to eliminate an excess of water. 相似文献
95.
Clemens Alexander Boecker Mara A. Olenick Elizabeth R. Gallagher Michael E. Ward Erika L. F. Holzbaur 《Traffic (Copenhagen, Denmark)》2020,21(1):138-155
Induced pluripotent stem cells (iPSCs) hold promise to revolutionize studies of intracellular transport in live human neurons and to shed new light on the role of dysfunctional transport in neurodegenerative disorders. Here, we describe an approach for live imaging of axonal and dendritic transport in iPSC‐derived cortical neurons. We use transfection and transient expression of genetically‐encoded fluorescent markers to characterize the motility of Rab‐positive vesicles, including early, late and recycling endosomes, as well as autophagosomes and mitochondria in iPSC‐derived neurons. Comparing transport parameters of these organelles with data from primary rat hippocampal neurons, we uncover remarkable similarities. In addition, we generated lysosomal‐associated membrane protein 1 (LAMP1)‐enhanced green fluorescent protein (EGFP) knock‐in iPSCs and show that knock‐in neurons can be used to study the transport of endogenously labeled vesicles, as a parallel approach to the transient overexpression of fluorescently labeled organelle markers. 相似文献
96.
Gemma Aragonès Kalavathi Dasuri Opeoluwa Olukorede Sarah G. Francisco Carol Renneburg Caroline Kumsta Malene Hansen Shun Kageyama Masaaki Komatsu Sheldon Rowan Jonathan Volkin Michael Workman Wenxin Yang Paula Daza Diego Ruano Helena Dominguez‐Martín José Antonio Rodríguez‐Navarro Xue‐Liang Du Michael A. Brownlee Eloy Bejarano Allen Taylor 《Aging cell》2020,19(11)
97.
98.
Natàlia de Martín Garrido Michael A. Crone Kailash Ramlaul Paul A. Simpson Paul S. Freemont Christopher H. S. Aylett 《Molecular microbiology》2020,113(1):143-152
Bacteriophage MS2 is a positive-sense, single-stranded RNA virus encapsulated in an asymmetric T = 3 pseudo-icosahedral capsid. It infects Escherichia coli through the F-pilus, in which it binds through a maturation protein incorporated into its capsid. Cryogenic electron microscopy has previously shown that its genome is highly ordered within virions, and that it regulates the assembly process of the capsid. In this study, we have assembled recombinant MS2 capsids with non-genomic RNA containing the capsid incorporation sequence, and investigated the structures formed, revealing that T = 3, T = 4 and mixed capsids between these two triangulation numbers are generated, and resolving structures of T = 3 and T = 4 capsids to 4 Å and 6 Å respectively. We conclude that the basic MS2 capsid can form a mix of T = 3 and T = 4 structures, supporting a role for the ordered genome in favouring the formation of functional T = 3 virions. 相似文献
99.
Sáenz-de la O Diana Cedillo-Jimenez Christopher Alexis García-Ortega Luis F. Martínez-Reséndiz Mariela Arné-Robles Diego Cruz-Hernandez Andrés Guevara-Gonzalez Ramón Gerardo 《Physiology and Molecular Biology of Plants》2020,26(1):3-13
Physiology and Molecular Biology of Plants - Transgenic tobacco (N. tabacum cv. Xanthi nc) expressing Capsicum chinense CchGLP gene that encodes an Mn-SOD, constitutively produces hydrogen... 相似文献
100.
Yasmin Vázquez-Santos Yuriana Martínez-Orea Javier Álvarez-Sánchez Noé Manuel Montaño Sara Lucía Camargo-Ricalde Silvia Castillo-Argüero 《Phyton》2021,90(2):605-619
The aim of this study was to analyze the performance of Acaena elongata colonized by arbuscular mycorrhizal
fungi (AMF) to different phosphorus (P) concentrations, as a measure of AMF dependency. A. elongata, is a species from soils where P availability is limited, such as temperate forests. Our research questions were: 1) How do
different P concentrations affect the AMF association in Acaena elongata, and 2) How does the AMF association
influence A. elongata’s growth under different P concentrations? A. elongata’s growth, P content in plant tissue,
AMF colonization and dependency were measured under four P concentrations: control (0 g P kg−1
), low
(0.05 g P kg−1
), intermediate (0.2 g P kg−1
) and high (2 g P kg−1
) in different harvests. A complete randomized
block design was applied. A. elongata’s growth was higher under -AMF in intermediate and high P concentrations, and the lowest growth corresponded to +AMF in the low and intermediate P concentration. We observed
a negative effect on the root biomass under +AMF in intermediate P concentration, while the P concentration had
a positive effect on the leaf area ratio. The AMF colonization in A. elongata decreased in the highest P concentration and it was favored under intermediate P concentration; while the low and the high concentrations generated a cost-benefit imbalance. Our results suggest that the performance of some plant species in soils with
low P availability may not be favored by their association with AMF, but a synergy between AMF and intermediate P concentrations might drive A. elongata’s growth. 相似文献