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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

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

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

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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

Advancements in personalized stem cell models for aging-related neurodegenerative disorders

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Neural regeneration research 2024年第11期19卷 2333-2334页

作者： Mingxi Weng ralf Jauch School of Biomedical Sciences Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Center for Translational Stem Cell Biology Hong Kong Special Administrative RegionChina

Neurodegenerative diseases(NDDs)are a class of disorders characterized by the gradual loss or malfunction of specific cell populations in the nervous system,which can be triggered by genetic or environmental *** a result,patients often experience a decline in mobility,sensation,memory,and cognition,which can ultimately lead to a fatal *** global incidence of NDDs,including Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,amyotrophic lateral sclerosis(ALS),and multiple sclerosis,is increasing.

关键词： degenerative Huntington sensation

Unraveling the gut-brain axis:the impact of steroid hormones and nutrition on Parkinson's disease

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Neural regeneration research 2024年第10期19卷 2219-2228页

作者： Paula Maria Neufeld ralf A.Nettersheim Veronika Matschke Matthias Vorgerd Sarah Stahlke Carsten Theiss Department of Cytology Institute of AnatomyMedical FacultyRuhr-University BochumBochumGermany Department of Visceral Surgery University Hospital BergmannsheilRuhr-University BochumBochumGermany Department of Neurology Heimer Institute for Muscle ResearchUniversity Hospital BergmannsheilRuhr-University BochumBochumGermany

This comprehensive review explores the intricate relationship between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the context of the gut-brain *** gut-brain axis plays a pivotal role in neurodegenerative diseases like Parkinson's disease,encompassing diverse components such as the gut microbiota,immune system,metabolism,and neural *** gut microbiome,profoundly influenced by dietary factors,emerges as a key *** during the first 1000 days of life shapes the gut microbiota composition,influencing immune responses and impacting both child development and adult ***-fat,high-sugar diets can disrupt this delicate balance,contributing to inflammation and immune *** nutritional strategies,the Mediterranean diet's anti-inflammatory and antioxidant properties show promise in reducing Parkinson's disease ***-targeted dietary approaches and the ketogenic diet hold the potential in improving brain *** nutrition,emerging research uncovers potential interactions between steroid hormones,nutrition,and Parkinson's ***,with its anti-inflammatory properties and presence in the nervous system,offers a novel option for Parkinson's disease *** ability to enhance neuroprotection within the enteric nervous system presents exciting *** review addresses the hypothesis thatα-synuclein aggregates originate from the gut and may enter the brain via the vagus *** symptoms preceding motor symptoms support this *** gut-brain signaling during gut dysbiosis contributes to inflammation and neurotransmitter imbalances,emphasizing the potential of microbiota-based *** summary,this review uncovers the complex web of interactions between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the gut-brain axis *** these connections not only offers novel therapeutic insi

关键词： diet gut-brain axis microbiome neurodegenerative diseases nutrition Parkinson's disease progesterone steroid hormones

Novel C_(sf)/SiBCN composites prepared by densifying C_(sf)/MA-SiBCN with the PIP process:Oxidation behavior and damage mechanism

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Journal of Advanced Ceramics 2024年第5期13卷 666-678页

作者： Wenhao Dou Daxin Li Bingzhu Wang Zhihua Yang Jun Chen Dechang Jia ralf riedel Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Structural-Functional Integration Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China Chongqing research Institute of HIT Chongqing 401135China Beijing Institute of Control Engineering Beijing 100094China Institut für Materialwissenschaft Technische Universität DarmstadtDarmstadt D-64287Germany School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

To improve the oxidation resistance of short carbon fiber(C_(sf))-reinforced mechanically alloyed SiBCN(MA-SiBCN)(C_(sf)/MA-SiBCN)composites,dense amorphous C_(sf)/SiBCN composites containing both MA-SiBCN and polymer-derived ceramics SiBCN(PDCs-SiBCN)were prepared by repeated polymer infiltration and pyrolysis(PIP)of layered C_(sf)/MA-SiBCN composites at 1100℃,and the oxidation behavior and damage mechanism of the as-prepared C_(sf)/SiBCN at 1300–1600℃ were compared and discussed with those of C_(sf)/*** C_(sf)/MA-SiBCN composites resist oxidation attack up to 1400℃ but fail at 1500℃ due to the collapse of the porous framework,while the PIP-densified C_(sf)/SiBCN composites are resistant to static air up to 1600℃.During oxidation,oxygen diffuses through preexisting pores and the pores left by oxidation of carbon fibers and pyrolytic carbon(PyC)to the interior of the *** to the oxidative coupling effect of the MA-SiBCN and PDCs-SiBCN matrices,a relatively continuous and dense oxide layer is formed on the sample surface,and the interfacial region between the oxide layer and the matrix of the as-prepared composite contains an amorphous glassy structure mainly consisting of Si and O and an incompletely oxidized but partially crystallized matrix,which is primarily responsible for improving the oxidation resistance.

关键词： mechanically alloyed SiBCN(MA-SiBCN) polymer-derived ceramics SiBCN(PDCs-SiBCN) short carbon fiber-reinforced SiBCN(C_(sf)/SiBCN)composites polymer infiltration and pyrolysis(PIP) oxidation damage mechanism

The new kid on the block in insect pest management:sprayable rNAi goes commercial

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Science China(Life Sciences) 2024年第8期67卷 1766-1768页

作者： Junjie Yan ralf Nauen Stuart reitz Andrei Alyokhin Jiang Zhang David Mota-Sanchez Yonggyun Kim Subba reddy Palli Silvia I.rondon Brian A.Nault Juan Luis Jurat-Fuentes Michael S.Crossley William E.Snyder Angharad M.r.Gatehouse Myron P.Zalucki Bruce E.Tabashnik Yulin Gao State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China Bayer AG Crop Science DivisionR&DPest ControlMonheim 40789Germany Department of Crop and Soil Science Oregon State UniversityOntario 97914USA School of Biology and Ecology University of MaineOrono 04469USA Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureKey Laboratory of Synthetic BiologyMinistry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518000China Department of Entomology Michigan State UniversityEast Lansing 48864USA Department of Plant Medicals Andong National UniversityAndong 36729Republic of Korea Department of Entomology University of KentuckyLexington 40503USA Oregon State University Oregon Integrated Pest Management CenterCorvallis 97838USA Department of Entomology Cornell UniversityCornell AgriTechGeneva 14456USA Department of Entomology and Plant Pathology University of TennesseeKnoxville 37996USA Department of Entomology and Wildlife Ecology University of DelawareNewark 19716USA Department of Entomology University of GeorgiaAthensGeorgia 30602USA School of Natural and Environmental Sciences Newcastle UniversityNewcastle upon TyneNE17RUUK School of the Environment University of QueenslandBrisbane 4072Australia Shandong Engineering research Center for Environment-Friendly Agricultural Pest Management College of Plant Health and MedicineQingdao Agricultural UniversityQingdao 266109China Department of Entomology University of ArizonaTucson 85721USA National Center of Excellence for Tuber and root Crop research Chinese Academy of Agricultural SciencesBeijing 100081China

Insect pest damage to crops is a threat to global food security(Tilman et al.,2011).Climate change,the evolution of insecticide resistance,and the phasing out of insecticides due to environmental and safety concerns exacerbate this *** urgently need safe and effective crop protection tools to sustainably generate yields that meet ever-increasing global demand.

关键词： crops damage pest

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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

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