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In vivo oxidative stress alters thiol redox status of peroxiredoxin 1 and 6 and impairs rat sperm quality

Asian Journal of Andrology 2017年第1期19卷 73-79页

作者： Yannan Liu cristian O'Flaherty The Research Institute of the McGill University Health Centre Montreal QC H4A 3J1 Canada Department of Surgery (Urology Division) McGill University Montreal QC H4A 3J1 Canada Department of Obstetrics and Gynecology McGill University Montreal QC H4A 3J1 Canada Department of Pharmacology and Therapeutics McGill University Montreal QC H3G 1Y6 Canada

Oxidative stress, the imbalance between the production of reactive oxygen species （ROS） and antioxidant activity is a major culprit of male infertility. Peroxiredoxins （PRDXs） are major antioxidant enzymes of mammalian spermatozoa and are thiol oxidized and inactivated by ROS in a dose-dependent manner. Their deficiency and/or inactivation have been associated with men infertility. The aim of this study was to elucidate the impact of oxidative stress, generated by the in vivo tert-butyl hydroperoxide （tert-BHP） treatment on rat epididymal spermatozoa during their maturation process. Adult Sprague-Dawley males were treated with 300 -moles tert-BHP/kg or saline （control） per day intraperitoneal for 15 days. Lipid peroxidation （2-thibarbituric acid reactive substances assay）, total amount and thiol oxidation of PRDXs along with the total amount of superoxide dismutase （SOD）, motility and DNA oxidation （8-hydroxy-deoxyguanosine） were determined in epididymal spermatozoa. Total amount of PRDXs and catalase and thiol oxidation of PRDXs were determined in caput and cauda epididymis. While animals were not affected by treatment, their epididymal spermatozoa have decreased motility, increased levels of DNA oxidation and lipid peroxidation along with increased PRDXs （and not SOD） amounts. Moreover, sperm PRDXs were highly thiol oxidized. There was a differential regulation in the expression of PRDX1 and PRDX6 in the epididymis that suggests a segment-specific role for PRDXs. In conclusion, PRDXs are increased in epididymal spermatozoa in an attempt to fight against the oxidative stress generated by tert-BHP in the epididymis. These findings highlight the role of PRDXs in the protection of sperm function and DNA integrity during epididymal maturation.

关键词： antioxidant enzymes DNA oxidation epididymis reactive oxygen species spermatozoa thiol oxidation

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The glutamate metabotropic receptor 5(GRM5)gene is associated with beef cattle home range and movement tortuosity

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Journal of Animal Science and Biotechnology 2023年第1期14卷 72-87页

作者： cristian A.Moreno Garcia Huitong Zhou David Altimira Robyn Dynes Pablo Gregorini Sadeepa Jayathunga Thomas M.R.Maxwell Jonathan Hickford Department of Agricultural Sciences Faculty of Agriculture and Life SciencesLincoln UniversityPO Box 85084Lincoln 7647New Zealand. Exertion Games Lab 8 Scenic BoulevardClaytonVictoria 3800Australia. AgResearch Limited Lincoln Research CentreCnr Springs Road and Gerald StreetLincoln 7674New Zealand. Scion Tītokorangi Drive(formerly Long Mile Rd)Rotorua 3010New Zealand.

Background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating *** this study,we investigated for first time the genetic variation within a candidate‘grazing gene',the glutamate metabotropic receptor 5 gene(GRM5),and tested associations between variation in that gene and variation in grazing personality behaviours(GP-behaviours)displayed by free-ranging cows during winter grazing in the steep and rugged rangelands of New *** beef cows(n=303,from 3 to 10 years of age)were tracked with global positioning system(GPS)and,with 5-minutes(min)relocation frequency,various GP-behaviours were *** included horizontal and vertical distances travelled,mean elevation,elevation range,elevation gain,slope,home range and movement tortuosity,variously calculated using daily relocation trajectories with repeated measurements(i.e.,7 to 24 days(d))and satellite-derived digital elevation models(DEM).The different GP-behaviours were fitted into mixed models to ascertain their associations with variant sequences and genotypes of ***:We discovered three GRM5 variants(A,B and C)and identified the six possible genotypes in the cattle *** mixed models revealed that A was significantly associated with elevation range,home range and movement ***,GRM5 genotypes were associated(P<0.05)to home range and movement tortuosity,while trends suggesting association(P<0.1)were also revealed for elevation range and horizontal distance *** GP-behaviour models were improved by correcting for cow age-class as a fixed *** analysis of GP-behaviours averaged per cow age-class suggests that grazing personality is fully established as beef cows reached 4 years of *** range and movement tortuosity were not only associated with GRM5 variation,but also negatively correlated with each other(r=-0.27,P<0.001).Conclusions:There se

关键词： Animal personality Breeding programmes Genetic associations Grazing distribution Grazing patterns Steep and rugged terrain

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Role of copper nanoparticles in wound healing for chronic wounds:literature review

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Burns & Trauma 2022年第1期10卷 805-813页

作者： Jessica Salvo cristian Sandoval Escuela de Enfermería Facultad de CienciasUniversidad MayorChile Programa de Doctorado en Ciencias Morfológicas Facultad de MedicinaUniversidad de la FronteraAv.Francisco Salazar 011454811230TemucoChile Escuela de Tecnología Médica Facultad de SaludUniversidad Santo TomásLos Carreras 7535310431OsornoChile Departamento de Ciencias Preclínicas Facultad de MedicinaUniversidad de la FronteraAv.Francisco Salazar 011454811230TemucoChile

Chronic wounds are defined as wounds that fail to proceed through the normal phases of wound healing in an orderly and timely *** most common and inevitable impairment to wound healing is the installation of an infection,usually in the case of chronic ***,the objective of the present review was to identify the importance of copper nanoparticles in dressings for wound *** such as silver,gold and copper combat infectious processes through the inhibition of protein synthesis,peroxidation of the cell membrane and destroying the nucleic acids of bacteria and *** bioactive nanoparticles,copper plays a complex role in various cells,it modulates several cytokines and growth factor mechanisms of action and is essentially involved in all stages of the wound healing *** importantly,copper plays a key role in skin regeneration and angiogenesis and accelerates the healing process through induction of vascular endothelial growth factor(VEGF)and angiogenesis by hypoxia-induced factor-1-alpha(HIF-1α)action where copper enhances HIF-1αexpression and HIF-1αbinding to the critical motifs in the promoter and putative enhancer regions of HIF-1-regulated genes.

关键词： Angiogenesis Antimicrobial Nanoparticles Regeneration Wound healing Chronic wound VEGF HIF-1α

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Global Trends of Usage of Chlorophyll Fluorescence and Projections for the Next Decade

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Plant Phenomics 2020年第1期2卷 409-418页

作者： Alonso Zavafer Leen Labeeuw cristian Mancilla Research School of Biology The Australian National UniversityCanberraACTAustralia University of Technology Sydney Climate Change ClusterFaculty of ScienceSydneyNSW 2007Australia Independent Researcher La FloridaChile

Chlorophyll fluorescence is the most widely used set of techniques to probe photosynthesis and plant *** great versatility has given rise to different routine methods to study plants and *** three main technical platforms are pulse amplitude modulation(PAM),fast rise of chlorophyll fluorescence,and fast repetition ***-induced fluorescence(SIF)has also gained interest in the last few *** have compared their advantages and their underlying theory,with many arguments advanced as to which method is the most accurate and *** date,no data has assessed the exact magnitude of popularity and influence for each *** this work,we have taken the bibliometrics of the past decade for each of the four platforms,have evaluated the public scientific opinion toward each method,and possibly identified a geographical *** used various metrics to assess influence and popularity for the four routine platforms compared in this study and found that,overall,PAM currently has the highest values,although the more recent SIF has increased in popularity rapidly during the last *** indicates that PAM is currently one of the fundamental tools in chlorophyll fluorescence.

关键词： algae routine Fluorescence

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Sperm quality in mice acutely treated with parathion

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Asian Journal of Andrology 2000年第2期2卷 147-150页

作者： cristian Sobarzo Eduardo Bustos-Obregon Faculty of Basic Sciences Catholic University of Temuco and Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile. Santiage 7 Chile.Faculty of Basic Sciences Catholic University of Temuco and Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile. Santiage 7 Chile.

Aim: To investigate the toxic effect of a single injection of the organophosphorous agropesticide, parathion, on sper-matogenesis in immature male mice. Methods: Seven-day old mice received a single injection of parathion intraperi-toneally at a dose of 1/3 LD_50. The epididymal sperm count, sperm morphology and chromatin thermal stability wereanalyzed 28 and 50 days after injection. Results: Sperm counts were decreased and teratozoospermia and thermal de-naturation of DNA increased after parathion injection. Sperm parameters were changed to a greater extent in younger an-imals, denoting a higher lability of spermatogenic process at its beginning. The damages could recover a long time afterparathion administration. Conclusion: Organophosphorous agropesticides are testicular toxicants, eliciting reversiblecytotoxic and cytogenetic alterations in germ cells.

关键词： epididymis spermatozoa organophosphorous compounds agropesticides spermatogenesis

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Bi-normalized response spectra and seismic intensity in Bucharest for 1986 and 1990 Vrancea seismic events

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 125-135页

作者： Florin Pavel Radu Vacareanu cristian Neagu Andrei Pricopie Department of Reinforced Concrete Structures Technical University of Civil Engineering BucharestRomania Department of Strength of Materials Bridges and TunnelsTechnical University of Civil Engineering BucharestRomania

The Vrancea subcrustal earthquakes of August 30,1986 and May 30,1990 are the two most recent seismic events that have occurred in Romania with moment magnitudes M W ≥ *** spectral analysis of the strong ground motions recorded in Bucharest reveals that despite small differences in magnitude between the 1986 and 1990 earthquakes,their frequency contents are very different,sometimes even *** main focus of this study is to conduct a comparative analysis of the response spectra in terms of the bi-normalized response spectra(BNRS) proposed by Xu and Xie(2004 and 2007) for strong ground motions recorded in Bucharest during these two seismic *** mean absolute acceleration and relative velocity response spectra for the two earthquakes are discussed and ***,the mean bi-normalized absolute acceleration and normalized relative velocity response spectra with respect to the control period T C are computed for the ground motions recorded in Bucharest in 1986 and *** predominant period T P is also used in this study for the normalization of the spectral period ***,the methodology proposed by Martinez-Perreira and Bommer(1998) is applied in order to estimate the seismic intensity of the two *** results are discussed and several conclusions regarding the possibility of using the bi-normalized response spectra(BNRS) are given.

关键词： response spectra bi-normalized response spectra dynamic amplifi cation factor control period damage potential parameters

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Morphology, flight performance, and water crossing tendencies of Afro-Palearctic raptors during migration

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Current Zoology 2015年第6期61卷 951-958页

作者： Nicolantonio AGOSTINI Michele PANUCCIO cristian PASQUARETTA MEDRAPTORS (Mediterranean Raptor Migration Network) Via Mario Fioretti 18 00152 Rome Italy University of Pavia Department of Earth and Environmental Sciences Via Ferrata 9 27100 Pavia (PV) Italy Universit6 de Strasbourg IPHC 23 rue Becquerel 67087 Strasbourg France CNRS UMR7178 67037 Strasbourg France

Raptors primarily use soaring-gliding flight which exploits thermals and ridge lifts over land to reduce energetic costs. However during migration, these birds often have to cross water surfaces where thermal currents are weak; during these times, birds mainly use flapping (powered) flight which increases energy consumption and mortality risk. As a result, some species have evolved strategies to reduce the amount of time spent over water by taking extensive detours over land. In this paper, we conducted a meta-analysis of water-crossing tendencies in Afro-Palearctic migrating raptors in relation to their morphology, their flight performance, and their phylogenetic relationships. In particular, we considered the aspect ratio (calculated as the wing span squared divided by wing area), the energetic cost of powered flight, and the maximum water crossing length regularly performed by adult birds. Our results suggest that energy consumption during powered flight predominately affects the ability of raptors to fly over water surfaces.

关键词：飞行性能迁移过程形态分析过水能量消耗滑翔飞行进化策略亲缘关系

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Jet CAT P80 Thermal Analyses and Performance Assessment Using Different Fuels Types

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Journal of Thermal Science 2018年第4期27卷 389-393页

作者： Grigore CICAN Adina TOMA cristian PUSCASU Razvan CATANA Politehnica University of Bucharest Faculty of Aerospace Engineering 1-7 Polizu Street 011061 Bucharest 1 Romania National Research and Development Institute for Gas Turbines - COMOTI 220D Iuliu Maniu Ave Bucharest 6 Romania

The micro gas turbine propulsion systems represent a good choice for the unmanned aerial vehicles(UAVs). The present work monitors the engine parameters, correlating them with other important engine instrumentation data. The aim of this research was to study the operation of the Jet CAT using various types of fuels under various operating conditions: normal acceleration and sudden acceleration. The measured parameters were monitored under different conditions:(A) Engine operation at two different ambient temperatures – outdoor at 0oC and inside at 19oC; and(B) Using 4 fuel types: kerosene, diesel fuel, kerosene with 5% gasoline and kerosene with 10% gasoline. The relevance of this work is given by the fact that a detailed analysis is performed for the idle regime. The paper will present the detailed test plan used and the most relevant charts with the obtained results for: start time, force, temperature before turbine, fuel flow, depending on micro turbo engine speed.

关键词：燃料喷气打字 P80 热分析评价表演操作条件

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Multi-planet extrasolar systems-detection and dynamics

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Research in Astronomy and Astrophysics 2012年第8期12卷 1044-1080页

作者： cristian Beaug Sylvio Ferraz-Mello Tatiana A.Michtchenko Instituto de Astronomía Teóricay Experimental Observatório Astronómico de CórdobaUniversidad de CórdobaArgentina Instituto de Astronomia Geofísica e Cie ncias AtmosfricasUniversidade de So PauloBrasil

20 years after the discovery of the first planets outside our solar system, the current exoplanetary population includes more than 700 confirmed planets around main sequence stars. Approximately 50% belong to multiple-planet systems in very diverse dynamical configurations, from two-planet hierarchical systems to multiple resonances that could only have been attained as the consequence of a smooth large- scale orbital migration. The first part of this paper reviews the main detection tech- niques employed for the detection and orbital characterization of multiple-planet sys- tems, from the （now） classical radial velocity （RV） method to the use of transit time variations （TTV） for the identification of additional planetary bodies orbiting the same star. In the second part we discuss the dynamical evolution of multi-planet systems due to their mutual gravitational interactions. We analyze possible modes of motion for hi- erarchical, secular or resonant configurations, and what stability criteria can be defined in each case. In some cases, the dynamics can be well approximated by simple ana- lytical expressions for the Hamiltonian function, while other configurations can only be studied with semi-analytical or numerical tools. In particular, we show how mean- motion resonances can generate complex structures in the phase space where different libration islands and circulation domains are separated by chaotic layers. In all cases we use real exoplanetary systems as working examples.

关键词： planetary systems -- planetary systems: formation

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A Comparative Study on the Truck Frame Stiffness with Solid and Beam Element FEA Models

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Modern Mechanical Engineering 2023年第3期13卷 55-61页

作者： Shengyong Zhang Zack Gertzen Adam Manering cristian Jongkind Department of Mechanical and Civil Engineering College of Engineering and Sciences Purdue University Northwest Westville USA

Truck frames should be designed and fabricated with enough rigidity to avoid excessive deflections. Finite element analysis (FEA) plays an important role in all stages of frame designs. While being accurate, 3D solid element FEA models are built upon frame configuration details which are not feasible in the preliminary design stage, partially because of limited available design data of frames and heavy computation costs. This research develops 1D beam element FEA models for simulating frame structures. In this paper, the CAD model of a truck frame is first created. The solid element FEA analysis, which is adopted as the baseline in this study, is subsequently conducted for the stiffness of the frame, Next, beam element FEA analysis is performed for validating the feasibility of the beam element FEA model by comparing the results from the solid and beam element FEA models. It is found that the beam element FEA model can predict the frame stiffness with acceptable accuracy and reduce the computation cost significantly.

关键词： FEA Truck Frame Structural Stiffness 3D Solid Element 1D Beam Element

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