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41.
42.
Reinertson RC Nelson VA Aunon SM Schlegel TT Lindgren KN Kerstman EL Arya M Paloski WH 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2007,14(1):P9-13
The NASA artificial gravity-bed rest pilot study (AGPS) was designed to investigate the efficacy of daily exposure to a +Gz acceleration gradient for counteracting the physiologic decrements induced by prolonged bed rest. Test subjects were continuously monitored by a physician for signs and symptoms of pre-syncope, motion sickness, and arrhythmias while on the centrifuge. In this article, we have summarized the medical monitoring observations that were made during the AGPS and included an assessment of the relative usefulness of the information provided by the various monitoring tools in making a decision to terminate a centrifuge spin. 相似文献
43.
Gholipour Parsa Komaki Alireza Parsa Hesam Ramezani Mahdi 《Neurochemical research》2022,47(7):2090-2108
Neurochemical Research - Hippocampal oxidative stress has a vital role in the pathophysiology of Alzheimer’s disease (AD)-associated behavioral deficits. Ecdysterone (Ecdy), a natural product... 相似文献
44.
Aymer Andrés Vásquez-Ordó?ez Nicolas A. Hazzi David Escobar-Prieto Dario Paz-Jojoa Soroush Parsa 《ZooKeys》2015,(545):75-87
Whiteflies (Hemiptera, Aleyrodidae) are represented by more than 1,500 herbivorous species around the world. Some of them are notorious pests of cassava (Manihot
esculenta), a primary food crop in the tropics. Particularly destructive is a complex of Neotropical cassava whiteflies whose distribution remains restricted to their native range. Despite their importance, neither their distribution, nor that of their associated parasitoids, is well documented. This paper therefore reports observational and specimen-based occurrence records of Neotropical cassava whiteflies and their associated parasitoids and hyperparasitoids. The dataset consists of 1,311 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT’s Arthropod Reference Collection (CIATARC, Cali, Colombia). Eleven species of whiteflies, 14 species of parasitoids and one species of hyperparasitoids are reported. Approximately 66% of the whitefly records belong to Aleurotrachelus
socialis and 16% to Bemisia
tuberculata. The parasitoids with most records are Encarsia
hispida, Amitus
macgowni and Encarsia
bellottii for Aleurotrachelus
socialis; and Encarsia
sophia for Bemisia
tuberculata. The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF). 相似文献
45.
Syed Azfar Hussain Shiv O. Prasher Martin Chenier Gitanjali Arya 《World journal of microbiology & biotechnology》2011,27(9):2061-2069
Nitrate-N-removing bacterial strains were isolated from a constructed wetland soil treated with three ionophoric antibiotics:
monensin, salinomycin and narasin. Five isolates were selected after initial screening for nitrogen removing potential. Nucleotide
sequence analysis of the 16S rRNA gene showed that these isolates were highly similar to Bacillus, and Pseudomonas species. The isolates were assessed for their ability to grow in the presence of ionophoric antibiotics. All strains were
found to withstand these pharmaceuticals. In particular, Bacillus subtilis strain BRAZ2B was found to thrive in the drug-exposed wetland environment, showing higher nitrate removal rate than the uninoculated
control. The strains were also assessed for nitrogen removal potential under three different C/N ratios: 4, 8 and 12; optimum
removal efficiency was observed at C/N 8 for most isolates. 相似文献
46.
47.
Chin CD Laksanasopin T Cheung YK Steinmiller D Linder V Parsa H Wang J Moore H Rouse R Umviligihozo G Karita E Mwambarangwe L Braunstein SL van de Wijgert J Sahabo R Justman JE El-Sadr W Sia SK 《Nature medicine》2011,17(8):1015-1019
One of the great challenges in science and engineering today is to develop technologies to improve the health of people in the poorest regions of the world. Here we integrated new procedures for manufacturing, fluid handling and signal detection in microfluidics into a single, easy-to-use point-of-care (POC) assay that faithfully replicates all steps of ELISA, at a lower total material cost. We performed this 'mChip' assay in Rwanda on hundreds of locally collected human samples. The chip had excellent performance in the diagnosis of HIV using only 1 μl of unprocessed whole blood and an ability to simultaneously diagnose HIV and syphilis with sensitivities and specificities that rival those of reference benchtop assays. Unlike most current rapid tests, the mChip test does not require user interpretation of the signal. Overall, we demonstrate an integrated strategy for miniaturizing complex laboratory assays using microfluidics and nanoparticles to enable POC diagnostics and early detection of infectious diseases in remote settings. 相似文献
48.
Leukotriene B4 (LTB4) is secreted by chemotactic neutrophils, forming a secondary gradient that amplifies the reach of primary chemoattractants. This strategy increases the recruitment range for neutrophils and is important during inflammation. Here, we show that LTB4 and its synthesizing enzymes localize to intracellular multivesicular bodies, which, upon stimulation, release their content as exosomes. Purified exosomes can activate resting neutrophils and elicit chemotactic activity in an LTB4 receptor-dependent manner. Inhibition of exosome release leads to loss of directional motility with concomitant loss of LTB4 release. Our findings establish that the exosomal pool of LTB4 acts in an autocrine fashion to sensitize neutrophils towards the primary chemoattractant, and in a paracrine fashion to mediate the recruitment of neighboring neutrophils in trans. We envision that this mechanism is used by other signals to foster communication between cells in harsh extracellular environments. 相似文献
49.
Cardioprotective effects of erythropoietin in the reperfused ischemic heart: a potential role for cardiac fibroblasts 总被引:23,自引:0,他引:23
Parsa CJ Kim J Riel RU Pascal LS Thompson RB Petrofski JA Matsumoto A Stamler JS Koch WJ 《The Journal of biological chemistry》2004,279(20):20655-20662
Erythropoietin has recently been shown to have effects beyond hematopoiesis such as prevention of neuronal and cardiac apoptosis secondary to ischemia. In this study, we evaluated the in vivo protective potential of erythropoietin in the reperfused rabbit heart following ventricular ischemia. We show that "preconditioning" with erythropoietin activates cell survival pathways in myocardial tissue in vivo and adult rabbit cardiac fibroblasts in vitro. These pathways, activated by erythropoietin in both whole hearts and cardiac fibroblasts, are also activated acutely by ischemia/reperfusion injury. Moreover, in vivo studies indicate that erythropoietin treatment either prior to or during ischemia significantly enhances cardiac function and recovery, including left ventricular contractility, following myocardial ischemia/reperfusion. Our data indicate that a contributing in vivo cellular mechanism of this protection is mitigation of myocardial cell apoptosis. This results in decreased infarct size as evidenced by area at risk studies following in vivo ischemia/reperfusion injury, translating into more viable myocardium and less ventricular dysfunction. Therefore, erythropoietin treatment may offer novel protection against ischemic heart disease and may act, at least in part, by direct action on cardiac fibroblasts and myocytes to alter survival and ventricular remodeling. 相似文献
50.
Muscle ring finger protein-1 inhibits PKC{epsilon} activation and prevents cardiomyocyte hypertrophy 总被引:2,自引:0,他引:2
Arya R Kedar V Hwang JR McDonough H Li HH Taylor J Patterson C 《The Journal of cell biology》2004,167(6):1147-1159
Much effort has focused on characterizing the signal transduction cascades that are associated with cardiac hypertrophy. In spite of this, we still know little about the mechanisms that inhibit hypertrophic growth. We define a novel anti-hypertrophic signaling pathway regulated by muscle ring finger protein-1 (MURF1) that inhibits the agonist-stimulated PKC-mediated signaling response in neonatal rat ventricular myocytes. MURF1 interacts with receptor for activated protein kinase C (RACK1) and colocalizes with RACK1 after activation with phenylephrine or PMA. Coincident with this agonist-stimulated interaction, MURF1 blocks PKCepsilon translocation to focal adhesions, which is a critical event in the hypertrophic signaling cascade. MURF1 inhibits focal adhesion formation, and the activity of downstream effector ERK1/2 is also inhibited in the presence of MURF1. MURF1 inhibits phenylephrine-induced (but not IGF-1-induced) increases in cell size. These findings establish that MURF1 is a key regulator of the PKC-dependent hypertrophic response and can blunt cardiomyocyte hypertrophy, which may have important implications in the pathophysiology of clinical cardiac hypertrophy. 相似文献