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Estimate of oxygen consumption and intracellular zinc concentration of human spermatozoa in relation to motility

Asian Journal of Andrology 2003年第1期5卷 3-8页

作者： ralf r.henkel Kerstin Defosse Hans-Wilhelm Koyro Norbert Weissmann Wolf-Bernhard Schill Center for Dermatology and Andrology University D-35385 Giessen GermanyCenter for Dermatology and Andrology University D-35385 Giessen GermanyInstitute for Plant Ecology University D-35385 Giessen GermanyCenter for Internal Medicine Justus Liebig University D-35385 Giessen GermanyCenter for Dermatology and Andrology University D-35385 Giessen Germany

Aim: To investigate the human sperm oxygen/energy consumption and zinc content in relation to motility. Methods: In washed spermatozoa from 67 ejaculates, the oxygen consumption was determined. Following calculation o... 详细信息

ract>Aim: To investigate the human sperm oxygen/energy consumption and zinc content in relation to motility. Methods: In washed spermatozoa from 67 ejaculates, the oxygen consumption was determined. Following calculation of the total oxygen consumed by the Ideal Gas Law, the energy consumption of spermatozoa was calculated. In addition, the zinc content of the sperm was determined using an atomic absorption spectrometer. The resulting data were correlated to the vitality and motility. results: The oxygen consumption averaged 0.24μmol/106 sperm×24 h, 0.28μmol/106 live sperm×24 h and 0.85μmol/106 live & motile sperm×24 h. Further calculations revealed that sperm motility was the most energy consuming process (164.31 mJ/106 motile spermatozoa×24 h), while the oxygen consumption of the total spermatozoa was 46.06 mJ/106 spermatozoa×24 h. The correlation of the oxygen/ energy consumption and zinc content with motility showed significant negative correlations (r= -0.759; Pr=-0.441; Prespectively). However, when correlating sperm energy consumption with the zinc content, a significant positive relation (r=0.323; P=0.01) was observed. Conclusion: Poorly motile sperm are actually wasting the available energy. Moreover, our data clearly support the 'Geometric Clutch Model' of the axoneme function and demonstrate the importance of the outer dense fibers for the generation of sperm motility, especially progressive motility.

关键词： oxygen energy consumption human spermatozoa sperm motility zinc

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Laser-induced plasma formation in water with up to 400 mJ double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion henkel Michelle SIEMENS ralf METHLING Benjamin EMDE Jörg HErMSDOrF Steffen FrANKE Diego GONZALEZ Leibniz Institute for Plasma Science and Technology(INP) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea *** measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can *** emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic *** has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

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Leukocytes and oxidative stress： dilemma for sperm Function and male fertility

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Asian Journal of Andrology 2011年第1期13卷 43-52页

作者： ralf r.henkel Department of Medical Biosciences University of the Western Cape Bellville 7535 South Africa

Spermatozoa are constantly exposed to the interphase between oxidation through high amounts of reactive oxygen species （rOS） and leukocytes, and reduction by means of scavengers and antioxidants. Considering the very special functions as being the only cells with such high polarization and exerting their functions outside the body, even in a different individual, the female genital tract, the membranes of these cells are chemically composed of an extraordinary high amount of polyunsaturated fatty acids. This in turn, renders them very susceptible to oxidative stress, which is defined as an imbalance between oxidation and reduction towards the oxidative status. As a result, rOS deriving from both leukocytes and the male germ cells themselves cause a process called ＇lipid peroxidation＇ and other damages to the sperm cell. On the other hand, a certain limited amount of rOS iS essential in order to trigger vital physiological reactions in cells, including capacitation or the acrosome reaction in sperm. The treatment of patients with antioxidants to compensate the oxidative status caused by oxidative stress is highly debated as uncontrolled antioxidative treatment might derail the system towards the reduced status, which is also unphysiological and can even induce cancer. This paradox is called the ＇antioxidant paradox＇. Therefore, a proper andrological diagnostic work-up, including the evaluation of rOS levels and the antioxidant capacity of the semen, has to he carried out beforehand, aimed at keeping the fine balance between oxidation and scavenging of vital amounts of rOS.

关键词： antioxidants balance beneficial effects detrimental effects leukocytes male infertility reactive oxygen species sperm functions

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Sperm preparation： state-of-the-art--physiological aspects and application of advanced sperm preparation methods

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Asian Journal of Andrology 2012年第2期14卷 260-269页

作者： ralf henkel Department of Medical Biosciences University of the Western Cape Bellville 7535 South Africa

For assisted reproduction technologies （ArT）, numerous techniques were developed to isolate spermatozoa capable of fertilizing oocytes. While early methodologies only focused on isolating viable, motile spermatozoa, with progress of ArT, particularly intracytoplasmic sperm injection （ICSI）, it became clear that these parameters are insufficient for the identification of the most suitable spermatozoon for fertilization. Conventional sperm preparation techniques, namely, swim-up, density gradient centrifugation and glass wool filtration, are not efficient enough to produce sperm populations free of DNA damage, because these techniques are not physiological and not modeled on the stringent sperm selection processes taking place in the female genital tract. These processes only allow one male germ cell out of tens of millions to fuse with the oocyte. Sites of sperm selection in the female genital tract are the cervix, uterus, uterotubal junction, oviduct, cumulus oophorus and the zona pellucida. Newer strategies of sperm preparation are founded oni （i） morphological assessment by means of＇motile sperm organelle morphological examination （MSOM E）＇; （ii） electrical charge; and （ili） molecular binding characteristics of the sperm cell. Whereas separation methods based on electrical charge take advantage of the sperm＇s adherence to a test tube surface or separate in an electrophoresis, molecular binding techniques use Annexin V or hyaluronic acid （HA） as substrates. Techniques in this category are magnet-activated cell sorting, Annexin V-activated glass wool filtration, flow cytometry and picked spermatozoa for ICSI （PICSI） from HA-coated dishes and HA-containing media. Future developments may include raman microspectrometry, confocal light absorption and scattering spectroscopic microscopy and polarization microscopy.

关键词： advanced sperm selection biomimetics conventional sperm selection female genital tract physiological sperm selection

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Sperm cell biology： current perspectives and future prospects

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Asian Journal of Andrology 2011年第1期13卷 3-5页

作者： r John Aitken ralf r.henkel Discipline of Biological Sciences University of Newcastle Newcastle NSW 2308 Australia Department of Medical Biosdences University of the Western Cape Bellville 7535 South Africa

Major advances in biomolecular techniques as well as in the sensitivity and accuracy of mass spectrometers are transforming the scientific landscape by fueling unprecedented advances in analytical biochemistry--the ＇... 详细信息

关键词： Sperm cell biology perspectives

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Critical evaluation of two models of flow cytometers for the assessment of sperm DNA fragmentation:an appeal for performance verification

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Asian Journal of Andrology 2019年第5期21卷 438-444页

作者： rakesh Sharma Sajal Gupta ralf henkel Ashok Agarwal American Center for reproductive Medicine Cleveland ClinicClevelandOH 44195USA Department of Medical Bioscience University of the Western CapeBellville 7535South Africa

Lack of standardized,reproducible protocols and referencO values is among the challenges faced when using new or upgraded versions of instruments in reproductive laboratories and flow *** deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)assay combined with flow cytometry routinely used for diagnostic measurement of sperm DNA fragmentation(SDF)is a unique *** change in the setting of the standard instrument,including upgrades of hardware or software,can lead to different results and may affect clinicians'decision for ***,we compared TUNEL results of SDF obtained from a standard(C6)flow cytometer with a newer version of the same instrument(C6 Plus)and examined the cutoff,sensitivity,and specificity without calibration(adjustment)and after *** sperm preparation and matched acquisition settings were used to examine the performance of two flow *** strength of agreement of the results between the two observers was also *** adjustment of the settings,overall concordance became high and the two cytometers showed 100%positive and negative predictive value with 100%area under the *** overall correlation coefficient observed between C6 and C6 Plus was highly significant(Pr=0.992;95%confidence interval[Cl]:0.982-0.997).After adjustment,the two cytometers showed very high precisi on of 98%and accuracy of>99%.The in terobserver agreeme nt on C6 flow cytometer for the two observers was 0.801±0.062 and 0.746±0.044 for C6 *** demonstrated a strong agreement between the samples tested on the two flow cytometers after calibration and established the robustness of both instruments.

关键词： DNA fragmentation flow cytometer oxidative stress sperm TUNEL assay

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The new 6^(th) edition of the WHO Laboratory Manualfor the Examination and Processing of HumanSemen: is it a step toward better standard operatingprocedure?

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Asian Journal of Andrology 2022年第2期24卷 123-124页

作者： Eric Chung Mohamed Arafa Florence Boitrelle Hussein Kandil ralf henkel ramadan Saleh rupin Shah Paraskevi Vogiatzi Armand Zini Ashok Agarwal AndroUrology Centre BrisbaneQLD 4000Australia University of Queensland Princess Alexandra HospitalBrisbaneQLD 4000Australia American Center for reproductive Medicine Cleveland ClinicClevelandOH 44195USA Department of Andrology Cairo UniversityCairo 12613Egypt Department of Urology Hamad Medical CorporationDoha 122104Qatar reproductive Biology Fertility PreservationAndrologyCECOSPoissy HospitalPoissyParis 78300France Saclay University UVSQINRAEBREEDJouy-en-Josas 78350France Fakih IVF Fertility Center Abu Dhabi 51133UAE Department of Metabolism Digestion and ReproductionImperial College LondonLondon SW72AZUK Department of Medical Biosciences University of the Western CapeBellville 7530South Africa LogixX Pharma ThealeBerkshire GU154DUUK Department of Dermatology Venereology and AndrologyFaculty of MedicineSohag UniversitySohag 82518Egypt Department of Urology Lilavati Hospital and Research CentreMumbaiMaharashtra 400001India Andromed Health and reproduction Fertility Diagnostics LaboratoryMaroussiAthens 10431Greece Department of Surgery McGill UniversityMontrealQC H3A 0G4Canada

Semen analysis(SA)remains the cornerstone of male infertility evaluation and should ideally be performed by an accredited andrology laboratory or in vitro fertilization(IVF)clinics based on the standards defined by the World Health Organization(WHO)for the Examination and Processing of Human Semen and in accordance with the International Organization for Standardization’s Basic Semen Examination on Specification and Test Methods.

关键词： Basic Human corners

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The impact of male overweight on semen quality and outcome of assisted reproduction

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Asian Journal of Andrology 2014年第5期16卷 787-787页

作者： Kristian Leisegang ralf henkel School of Natural Medicine Faculty of Community and Health Sciences University of the Western Cape Bellville South Africa Department of Medical Bioscience Faculty of Science University of the Western Cape Bellville South Africa

The impact of obesity on male reproductive health remains a contested topic as evidence is inconclusive and inconsistent.1,2 Even more debatable is the effect of male obesity in assisted reproduction. In the manuscript, ＂the impact of male overweight on semen quality and outcome of assisted reproduction＂ published in Asian Journal ofAndrology, Thomsen et al.3 investigated the effect of male obesity on fertilization outcomes in intrauterine insemination, in vitro fertilization （IVF） and intracytoplasmic sperm injection （ICSI） programs further contributes to the increasing body of evidence in this field.

关键词： The impact male overweight

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完美自动化实现节能增效

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自动化博览 2009年第7期26卷 42-43页

作者： ralf henkel 贝加莱德国分公司

2007年，贝加莱向全球的机器和设备制造商提供了超过65000个伺服驱动器，而且有迅速增加的趋势。它为什么取得这样的成功？成功来自集成了节能解决方案的驱动技术。那么，谁将从这个方案中获益？谁又能持续从“插座”中获得动力？一份... 详细信息

2007年，贝加莱向全球的机器和设备制造商提供了超过65000个伺服驱动器，而且有迅速增加的趋势。它为什么取得这样的成功？成功来自集成了节能解决方案的驱动技术。那么，谁将从这个方案中获益？谁又能持续从“插座”中获得动力？一份详尽的效益分析报告也许能够提供一些答案。

关键词：节能增效自动化伺服驱动器设备制造商驱动技术效益分析

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Bibliometrics： tracking research impact by selecting Lhe appropriate metrics

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Asian Journal of Andrology 2016年第2期18卷 296-309,J0008页

作者： Ashok Agarwal Damayanthi Durairajanayagam Sindhuja Tatagari Sandro C Esteves Avi Harlev ralf henkel Shubhadeep roychoudhury Sheryl Homa Nicolas Garrido Puchalt ranjith ramasamy Ahmad Majzoub Kim Dao Ly Eva Tvrda Mourad Assidi Kavindra Kesai reecha Sharma Saleem Banihani Edmund Ko Muhammad Abu-Elmagd Jaime Gosalvez Asher Bashiri American Center for reproductive Medicine Cleveland Clinic Cleveland OH USA Faculty of Medicine Universiti Teknologi MARA Selangor Malaysia Case Western reserve University Cleveland OH USA Androfert Andrology and Human Reproduction Clinic Campinas Brazil Department of Obstetrics and Gynecology Soroka University Medical Center Ben Gurion University of the Negev Beersheba Israel Department of Medical Bioscience University of the Western Cape Bellville South Africa Department of Life Science and Bioinformatics Assam University Silchar Assam India Andrology Solutions London UK IVF Laboratory Instituto Universitario IVI Valencia Valencia Spain Department of Urology Unwersity of Miami Miller School of Medicine Miami Florida USA Texas A and M Health Science Center College of Medicine Bryan Texas USA Department of Animal Physiology Slovak University of Agricuiture Nitra Siovakia Center of Excellence in Genomic Medicine research King Abdulaziz University Jeddah KSA School of Life Sciences Jaipur National UnJversity Jaipur Rajasthan India Department of Health Services Saint Joseph's University Philadelphia PA USA Department of Medical Laboratory Sciences Jordan university of science and Technology Irbid Jordan Department of Urology Loma Linda University School of Medicine Loma Linda California USA Department of Biology Genetics Unit Autonomous University of Madrid MadridSpain Maternal-Fetal Medicine and Ultrasound Soroka University Medical Center Ben-Gurion University of the NegevBeersheba Israel.

Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a specific researcher, is assessed through the use of various metrics. While researchers may be acquainted with such matrices, many do not know how to use them to enhance their careers. In addition to these metrics, a number of other factors should be taken into consideration to objectively evaluate a scientist＇s profile as a researcher and academician. Moreover, each metric has its own limitations that need to be considered when selecting an appropriate metric for evaluation. This paper provides a broad overview of the wide array of metrics currently in use in academia and research. Popular metrics are discussed and defined, including traditional metrics and article-level metrics, some of which are applied to researchers for a greater understanding of a particular concept, including varicocete that is the thematic area of this Special Issue of Asian Journal of Andrology. We recommend the combined use of quantitative and qualitative evaluation using judiciously selected metrics for a more objective assessment of scholarly output and research impact.

关键词： article-level metrics bibliometrics citation counts h-index impact factor research databases research impact research productivity traditional metrics

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