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Stem cell therapy for the treatment of Leydig cell dysfunction in primary hypogonadism

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World journal of Stem Cells 2016年第10期8卷 306-315页

作者： taylor C Peak Nora M Haney William Wang Kenneth j DeLay Wayne j Hellstrom Department of Urology School of MedicineTulane University

The production of testosterone occurs within the Leydig cells of the testes. When production fails at this level from either congenital, acquired, or systemic disorders,the result is primary hypogonadism. While numerous testosterone formulations have been developed, none are yet fully capable of replicating the physiological patterns of testosterone secretion. Multiple stem cell therapies to restore androgenic function of the testes are under investigation. Leydig cells derived from bone marrow, adipose tissue, umbilical cord, and the testes have shown promise for future therapy for primary hypogonadism. In particular, the discovery and utilization of a group of progenitor stem cells within the testes, known as stem Leydig cells(SLCs), has led not only to a better understanding of testicular development, but of treatment as well. When combining this with an understanding of the mechanisms that lead to Leydig cell dysfunction, researchers and physicians will be able to develop stem cell therapies that target the specific step in the steroidogenic process that is deficient. The current preclinical studies highlight the complex nature of regenerating this steroidogenic process and the problems remain unresolved. In summary, there appears to be two current directions for stem cell therapy in male primary hypogonadism. The first method involves differentiating adult Leydig cells from stem cells of various origins from bone marrow, adipose, or embryonic sources. The second method involves isolating, identifying, and transplanting stem Leydig cells into testicular tissue. Theoretically, in-vivo re-activation of SLCs in men with primary hypogonadism due to age would be another alternative method to treat hypogonadism while eliminating the need for transplantation.

关键词： Stem cell therapy Leydig cells Primary hypogonadism Stem Leydig cells Testosterone Bone marrow-derived stem cells Adipose-derived mesenchymal stem cells

Trans-Gulf of Mexico loop migration of tree swallows revealed by solar geolocation

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Current Zoology 2014年第5期60卷 653-659页

作者： David W. BRADLEY Robert G. CLARK Peter O. DUNN andrew j. LAUGHLIN Caz M. taylor Carol VLECK Linda A. WHITTINGHAM David W. WINKLER D. Ryan NORRIS Department of Integrative Biology University of Guelph Guelph Ontario N1G 2W 1 Canada Bird Studies Canada Port Rowan Ontario N0E 1M0 Canada Environment Canada. Saskatoon. Saskatchewan S7N 0X4. Canada Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin Milwaukee Wisconsin 53201 USA Department of Ecology and Evolutionary Biology Tulane University New Orleans Louisiana 70118 USA Department of Ecology Evolution and Organismal Biology Iowa State University Ames IA 50011-1020 USA Department of Ecology and Evolutionary Biology Museum of Vertebrates and Lab of Ornithology Comell University Ithaca New York 14853 USA

One of the greatest feats of avian migration is the non-stop crossing of extensive areas of inhospitable habitat such as deserts and seas. Differences in spring and autumn migration routes have been reported in species that cross such barriers, and are thought to have evolved in response to seasonal variation in prevailing wind direction. We tested the hypothesis that migration routes vary seasonally with respect to the Gulf of Mexico in the tree swallow Tachycineta bicolor using solar geolocators attached and retrieved at 4 breeding sites in central North America. We found that 100 % of birds （n = 10） made a trans-Gulf flight of 〉850 km from Louisiana south to their wintering grounds in the Yucatan Peninsula in 12-36 hours, achieving minimum ground speeds as high as 32 m/s. Although most days during autumn migration were characterized by unfavorable headwinds blowing to the northwest, migration over the Gulf mostly occurred on days with strong winds blowing to the south. In contrast, in 8 of 9 （88 %） birds on spring migration returned from the wintering grounds towards Louisiana following a clockwise loop pat- tern flying over land to the west around the Gulf. During this spring period there were few days with prevailing winds from the south to assist northward migration. Results suggest that, despite being up to three times further （ca. 2,700 kin）, a coastal circum-Gulf spring migration represents the less risky route when wind conditions are not favorable. These findings also help to resolve a long-standing dispute in the literature concerning migration patterns between the US Gulf coast and Mexico, and provide insight into the factors shaping migration strategies of small songbirds migrating across large bodies of water [Current Zoology 60（5）： 653-559, 2014].

关键词： Ecological Barrier Geolocation Gulf of Mexico Tachycineta bicolor Tree swallow Migration

Compositionally restricted attention-based network for materials property predictions

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npj Computational Materials 2021年第1期7卷 684-693页

作者： Anthony Yu-Tung Wang Steven K.Kauwe Ryan j.Murdock taylor D.Sparks Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials Technische Universität BerlinBerlinGermany Department of Materials Science&Engineering University of UtahSalt Lake CityUTUSA

In this paper,we demonstrate an application of the Transformer self-attention mechanism in the context of materials *** network,the Compositionally Restricted Attention-Based network(CrabNet),explores the area of structure-agnostic materials property predictions when only a chemical formula is *** results show that CrabNet’s performance matches or exceeds current best-practice methods on nearly all of 28 total benchmark *** also demonstrate how CrabNet’s architecture lends itself towards model interpretability by showing different visualization approaches that are made possible by its *** feel confident that CrabNet and its attention-based framework will be of keen interest to future materials informatics researchers.

关键词： network property restricted

Impact of rewilding,species introductions and climate change on the structure and function of the Yukon boreal forest ecosystem

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Integrative Zoology 2018年第2期13卷 123-138页

作者： Rudy BOONSTRA Stan BOUTIN Thomas S.jUNG Charles j.KREBS Shawn taylor Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada Department of Biological Sciences University of AlbertaEdmontonAlbertaCanada Department of Environment Government of YukonWhitehorseYukonCanada Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada

Community and ecosystem changes are happening in the pristine boreal forest ecosystem of the Yukon for 2 ***,climate change is affecting the abiotic environment(temperature,rainfall and growing season)and driving changes in plant productivity and predator-prey ***,simultaneously change is occurring because of mammal species reintroductions and *** key ecological question is the impact these faunal changes will have on trophic *** productivity in the boreal forest is increasing because of climatic warming,but plant species composition is unlikely to change significantly during the next 50-100 *** 9-10-year population cycle of snowshoe hares will persist but could be reduced in amplitude if winter weather increases predator hunting *** rodents have increased in abundance because of increased vegetation *** ground squirrels have disappeared from the forest because of increased predator hunting efficiency associated with shrub *** have occurred for 2 reasons:human reintroductions of large ungulates and natural recolonization of mammals and birds extending their geographic *** deliberate rewilding of wood bison(Bison bison)and elk(Cervus canadensis)has changed the trophic structure of this boreal ecosystem very *** natural range expansion of mountain lions(Puma concolor),mule deer(Odocoileus hemionus)and American marten(Martes americana)should have few ecosystem *** potential changes will require long-term monitoring studies and experiments on a scale we rarely deem *** affected by climate change,species reintroductions and human alteration of habitats cannot remain stable and changes will be critically dependent on food web interactions.

关键词： community stability introduced species population cycles trophic dynamics

Study on the early surface films formed on Mg-Y molten alloy in different atmospheres

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journal of Magnesium and Alloys 2015年第3期3卷 173-179页

作者： A.R.Mirak C.j.Davidson j.A.taylor CAST CRC School of Mechanical and Mining EngineeringThe University of QueenslandBrisbaneQLD 4072Australia CAST CRC CSIRO Materials Science and EngineeringP.O.Box 883KenmoreQLD 4069Australia

In the present study,the non-isothermal early stages of surface oxidation of liquid Mg-1%Y alloy during casting were studied under UPH argon,dry air,and air mixed with protective fluorine-bearing *** chemistry and morphology of the surface films were characterized by SEM and EDX *** results indicate a layer of smooth and tightly coherent oxidation film composed of MgO and Y_(2)O_(3) formed on the molten Mg-Y alloy surface with 40-60 nm thickness under dry air.A dendritic/cellular microstructure is clearly visible with Y-rich second phases gathered in surface of the melt and precipitated along the grain/cell boundaries under all gas *** fluorine-bearing gas mixtures,the surface film was a mixed oxide and fluoride and more even;a flat and folded morphology can be seen under SF6 with oxide as dominated phase and under 1,1,1,2-tetra-fluoroethane,a smooth and compact surface film uniformly covering the inner surface of the bubble with equal oxide and fluoride thickness,which results in a film without any major ***_(2) phase appears to be the key characteristic of a good protective film.

关键词： Mg-Y alloy SEM EDX Early surface film Oxidation Fluoridation

Behavioral and neural auditory thresholds in a frog

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Current Zoology 2019年第3期65卷 333-341页

作者： Ryan C.taylor Karin AKRE Walter WILCZYNSKI Michael j.RYAN Department of Integrative Biology University of Texas at Austin Austin TX USA Department of Biological Sciences Salisbury University Salisbury MD USA Smithsonian Tropical Research Institute Balboa Republic of Panama Neuroscience Institute and Center for Behavioral Neuroscience Georgia State University Atlanta GA USA

Vocalizations play a critical role in mate recognition and mate choice in a number of taxa, especially, but not limited to, orthopterans, frogs, and birds. But receivers can only recognize and prefer sounds that they can hear. Thus a fundamental question linking neurobiology and sexual selection asks-what is the threshold for detecting acoustic sexual displays? In this study, we use 3 methods to assess such thresholds in tdngara frogs: behavioral responses, auditory brainstem responsesz and multi unit electrophysiological recordi ngs from the *** show that thresholds are lowest for multiunit recordings (ca. 45 dB SPL), and then for behavioral responses (ca. 61 dB SPL), with auditory brainstem responses exhibiting the highest thresholds (ca. 71 dB SPL). We discuss why these estimates differ and why, as with other studies, it is unlikely that they should be the same. Although all of these studies estimate thresholds they are not measuring the same thresholds;behavioral thresholds are based on signal salienee whereas the 2 neural assays estimate physiological thresholds. All 3 estimates, however, make it clear that to have an appreciation for detection and salienee of acoustic signals we must listen to those signals through the ears of the receivers.

关键词： anurans auditory brainstem responses auditory thresholds mate choice Physalaemus pustulosus signal recog nition thresholds sexual selection tungara frogs vocalizations

Chilli anthracnose disease caused by Colletotrichum species

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journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第10期9卷 764-778页

作者： Po Po THAN Haryudian PRIHASTUTI Sitthisack PHOULIVONG Paul W.j.taylor Kevin D.HYDE International Fungal Research and Development Centre the Research Institute of Resources InsectChinese Academy of ForestryKunming 650224ChinaBioMarkaSchool of Agriculture and Food SystemsUniversity of MelbourneVictoria 3010Australia Fungal Research Group School of ScienceMae Fah Luang UniversityTasudChiang Rai 57100ThailandDepartment of BiotechnologyFaculty of AgricultureBrawijaya UniversityMalang 65145Indonesia Fungal Research Group School of ScienceMae Fah Luang UniversityTasudChiang Rai 57100ThailandMushroom Research Centre128 Moo 3 T. Pa PaeA. Mae TaengChiang Mai 50150Thailand6Department of Plant ScienceFaculty of AgricultureNational University of LaosVientianeLao PDR BioMarka School of Agriculture and Food SystemsUniversity of MelbourneVictoria 3010Australia International Fungal Research and Development Centre the Research Institute of Resources InsectChinese Academy of ForestryKunming 650224ChinaFungal Research GroupSchool of ScienceMae Fah Luang UniversityTasudChiang Rai 57100Thailand

Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.

关键词： Capsicum annuum Disease management Identification Taxonomy Pathogenicity

Insights into the role of jasmonic acid-mediated defenses against necrotrophic and biotrophic fungal pathogens

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Frontiers in Biology 2012年第1期7卷 48-56页

作者： Christopher j. ANTICO Chad COLON taylor BANKS Katrina M. RAMONELL Department of Biological Sciences University of Alabama Tuscaloosa AL 35487 USA

jasmonic acid （jA） is a natural hormone regulator involved in development, responses against woundingand pathogen attack. Upon perception of pathogens, jA is synthesized and mediates a signaling cascade initiating various defense responses. Traditionally, necrotrophic fungi have been shown to be the primary activators of jA- dependent defenses through the jA-receptor, COIl. Conversely, plants infected with biotrophic fungi have classically been associated with suppressing jA-mediated responses. However, recent evidence has shown that certain biotrophic fungal species also trigger activation of jA-mediated responses and mutants deficient in jA signaling show an increase in susceptibility to certain biotrophic fungal pathogens. These findings suggest a new role for jA in defense against fungal biotrophs. This review will focus on recent research advancing our knowledge of jA-dependant responses involved in defense against both biotrophic and necrotrophic fungi.

关键词： jasmonic acid (jA) methyl jasmonate (MejA) biotrophic fungi necrotrophic fungi COIl

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整体级联式增压空气冷却器的进气模块

汽车与新动力 2014年第4期46卷 48-52页

作者： j.Stehlig R.Dingelstadt R.Müller j.taylor 范明强

提高涡轮增压发动机的增压压力会造成增压空气温度升高,这不仅会提高增压空气冷却器和进气模块的热负荷,而且,增压空气温度高对燃烧也有不利影响,不仅会使燃油耗升高,还会恶化发动机的扭矩输出和加速响应性能。Mahle公司和Behr公司开发... 详细信息

提高涡轮增压发动机的增压压力会造成增压空气温度升高,这不仅会提高增压空气冷却器和进气模块的热负荷,而且,增压空气温度高对燃烧也有不利影响,不仅会使燃油耗升高,还会恶化发动机的扭矩输出和加速响应性能。Mahle公司和Behr公司开发了一种整体级联式增压空气冷却器,大力推动了整体式间接增压空气冷却器的发展。

关键词：增压空气冷却器增压空气温度汽油机扭矩燃油耗