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大鼠内源性糖皮质激素对间质细胞功能的影响

男性学杂志 1997年第2期11卷 65-70页

作者：高惠宝 GE Renshan m.p.hardy 上海第二医科大学生殖生物学实验室人口委员会生物医学研究中心（美国）

本文旨在评价大鼠体内糖皮质激素（大鼠体内是皮质酮）对间质细胞中睾酮合成和１１－β羟类固醇脱氢酶（１１β－ＨＳＤ）活性的影响。为观察内源性皮质酮对间质细胞中睾酮合成的影响，本文测定了切除肾上腺雄性大鼠（４５天龄）血清皮... 详细信息

本文旨在评价大鼠体内糖皮质激素（大鼠体内是皮质酮）对间质细胞中睾酮合成和１１－β羟类固醇脱氢酶（１１β－ＨＳＤ）活性的影响。为观察内源性皮质酮对间质细胞中睾酮合成的影响，本文测定了切除肾上腺雄性大鼠（４５天龄）血清皮质酮、睾酮，ＬＨ含量和经ＬＨ刺激的纯化间质细胞中睾酮生成量及纯化间质细胞中１１β－ＨＳＤ活性水平。结果表明，切除肾上腺后大鼠血清睾酮水平高于手术对照组及切除后补充皮质酮大鼠。切除肾上腺后大鼠和切除后补充皮质酮大鼠血清ＬＨ水平均无明显变化，表明在上述二实验组中，由于内源性皮质酮变化而导致的间质细胞中睾酮生成的变化不依赖ＬＨ的存在。切除肾上腺后大鼠其纯化的间质细胞睾酮生成量比对照组增加一倍。但经补充皮质酮后睾酮生成量被抑制到对照组水平以下，表明给切除肾上腺后大鼠补充皮质酮能明显地抑制睾酮生成。切除肾上腺后大鼠间质细胞中１１β－ＨＳＤ活性降低，并且这一降低可经补充皮质酮得到恢复。上述结果表明生理性浓度皮质酮对间质细胞中睾酮合成行使直接的负性控制，同时诱导细胞内１１β－ＨＳＤ活性，由此保护间质细胞中睾酮合成免于受到糖皮质激素的过度抑制。

关键词：糖皮质激素间质细胞睾酮合成 11β-HSD

molecular Dynamics Simulation of mgSiO_(3) perovskite

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Chinese physics Letters 1998年第6期15卷 444-446页

作者： ZHOU Lin-xiang J.R.hardy XU Xin Department of physics Xiamen UniversityXiamen 361005 Department of physics and Center for Electro-Optics University of Nebraska-LincolnNE 68588-0111U.S.A State Key Laboratory for physical Chemistry of Solid Surfaces Department of ChemistryXiamen UniversityXiamen 361005

Using molecular dynamics to simulate mgSiO_(3) perovskite is performed to investigate its phase transitions and *** simulations has used parameter-free Gordon-Kim potentials and a novel technique to monitor the motion of ions which clearly demonstrates the sublattice melting of ions O^(2-) and the rotations of SiO_(6) ***_(3) has to undergo a few of phase transitions,then enter into the cubic *** particular,there is a transitional phase between orthorhombic phase and cubic *** are a superionc phase and the cubic phase in magnesium-rich silicate *** superionic phase occurs after the onset of cubic phase before the melting *** onset temperature T_(c) for superionicity is about 200-700K below the melting point T_(m),T_(c)/T_(m)~0.92.

关键词： cubic perovskite transitions

Arrested proliferation of progenitor and Immature Leydig Cells Accounting For the Reduced Leydig Cell Number in Igf-I Null mice

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Arrested Proliferation of Progenitor and Immature Leydig Cel...

2006年浙江省病理学术会议暨第三届中国国际淋巴造血系...

作者： Chantal m Sottas matthew p hardy Center for Biomedical Research Population Council and Rockefeller UniversityNew YorkNYUnited States10021 Center for Biomedical Research Population Council and Rockefeller UniversityNew YorkNYUnited States10021

＜Abstract＞Aim Backgound: Normal numbers of adult Leydig cells per testis are is maintained primarily from the normal proliferation of its progenitors. postnatal development of Leydig cells in rodents can be divided into four distinct stages of differentiation: initially fibroblast-like stem Leydig cells （SLC） proliferates by postnatal days （pND） 7 to 14, and then they commit to fibroblast-like progenitors （pLC） by 14-21;subsequently, as immature Leydig cells （ILC） by day 21-35, they acquire steroidogenic organelle structure and enzyme activities but metabolize most of the testosterone they produce;finally, as adult Leydig cells （ALC） by day 90 they actively produce testosterone. Targeted gene deletion of insulin-like growth factor-I （IGF-I） results in diminished numbers of Leydig cells （LCs） and lower circulating testosterone levels in adult males. Aim: The aims of the present study were to determine dynamic proliferating and differentiating profiles of adult Leydig cell population during postnatal period in IGF-I null mice. methods: Testicular cells in mice were labeled by injection of BrDU and testes were collected by pND14, 21, 28, 56 and 90. Leydig cells were immunohistochemically stained using 3β-hydroxysteroid dehydrogenase antibody and analyzed using a imaging analytical software. Results: SLC become proliferative at pND 14 in wild-typed testis with labeling index of 10.8±4.6 （mean±SEm）, LI of SLC greatly decreased through pND 21-56, and LI peaked for pLC at pND 21 and LI for LC peaked at pND 35. LI of SLC did not change in IGF-I null mice （7.4±3.3） compared to wild-type mice, while pLC and ILC did not proliferate through pND 14 to pND90. The Leydig cell number and cell size were significantly reduced in IGF-I mutant adult testis, e.g. at pND90, 980±155 cells/mm2 and 132.6±6.4μm2 compared to 1876±116 cells/mm2 and 280.9±10.6 μm2 in wild-type testis, respectively. The differentiation of SLC into pLC was not affected since the numbers of pLC formed at pND14 was

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Nicotine Acetylcgoline Receptor Expression and Nicotineinduced modulation of Testosterone(T) producton in rat leydig cells

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Nicotine Acetylcgoline Receptor Expression and Nicotineinduc...

2006年浙江省病理学术会议暨第三届中国国际淋巴造血系统疾病诊断及治疗新进展研讨会

作者： Chantal m.Sottas matthew p.hardy population Council Now YorkNew York 10021 USA

It has been reported that neuronal signaling directly controls Leydig cell steroidogenic function. Neuronal pathways to the testis and to the vicinity of Leydig cells have been demonstrated, but neurotransmitter senstitivity in these cells has remained unclear. The objectives of the present study were to determine if acetylcholine receptors (AchRs) are expressed in Leydig cells. progenitor, immature and adult Leydig cells were purified from 21-, 35-and 90-day-old male Sprague Dawley rats, respectively, and AchR messenger RNA levels were measured by DNA macro- arrays. The nicotinic-AchR subunits α1,α2,α3,α4,α5,α6,α7,β1,β2,Δ,γ,and σ,and muscarinic AchR m2 through m5 were all included in the analysis. Subunits α1,α5, α4, α6,β1, β2, and σ were detected above significant signal threshold levels. None of the muscarinic receptor forms were detected. Subunit α4 had the highest signal level: it was undetectable in progenitor Leydig cells and increased sharply during the transitions to immature and adult Leydig cell by up to 100 fold. Transcript levels for the enzyme acetylcholinseterase, which metabolizes Ach, were also abundant. Adult Leydig cells were cytotoxically eliminated from adult testes by administration of the drug ethylene dimethanesulfonate. This induced Leydig cell regeneration, and it was noted that a4 subunit expression was eliminated along with the Leydig cells and reappeared only after 35 days with the restoration of normal serum testosterone concentrations. purified adult Leydig cells were treated with different concentrations of nicotine (10-7 to 10-3m) for 3 hours. Nicotine exerted a biphasic dose response for LH stimulated T production. Lower doses, 10-5m, increased T levels by 20% (control 141±5 vs.171±9ng/106cell·3hr), whereas higher doses,e.g., 10-3m,lowered T production by 50% (71±1ng/106cells·3hr). Therefore, at physiological concentrations of agonist, the AchR pathway is stimulatory. These data suggest that nicotinic AchR signaling may be

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Development of a cryopreservation protocol for leydig cells

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Development of a cryopreservation protocol for leydig cells

2006年浙江省病理学术会议暨第三届中国国际淋巴造血系统疾病诊断及治疗新进展研讨会

作者： Chatal m.Sottas matthew p.hardy population Council New YorkNew York 10021USA

Lmplantation of Leydig cells either in suspension or encapsulated in alginatepoly-Llysine microspheres has been proposed as a possible treatment of hypogonadism. A protocol for effective cryopreservation of these cells pror to implantation has been developed. progenitor(pLC), immature(lLc)and adult rat Leydig cells (ALC)were purified from 21-35-and 90-dayold rats by percoll separation. The cells were re-suspended in a culture medium supplemented with 1% bovine serum albumin (S-DmEm/F12)in a final concentration of 2×106 cells/mL, and the effects of varying concentrations of dimethylsulfoxide(DmSO,10,15or20%)were assessed after freezing at -70℃ and then liquid nitrogen After 12 months of frozen storage, these cells were thawed rapidly at 37℃ and trypan blue exclusion staining and attachment to culture dishes were assessed as measures of viability. The viabilities for pLC,ILC, and ALC were over85% in the presence of 15% DmSO. Increasing the concentration of fetal calf serum (FCS)in the DmSO-based medium to 20% had no effect on survival after freezing and thawing. In consideration of possible effects of FCS components on steroidogenic function, a serum-free cryopreservative medium was adopted. S-DmEm/F12+15%DmSO. After 12 months in this medium at liquid nitrogen, the Leydig cell steroidogenic capacity in response to maximal challenge doses of luteinizing hormone(LH, 100ng/mL) was unchanged compared to freshly isolated control cells (e.g.,ILC freshly isolated 27.36±4.74 vs. frozen 30.14±1.43ng/106cell ·3hr). Furthermore, the steady state messenger RNA levels for Leydig cell specific transcripts including LH receptor, steroidoenic acute regulatory protein(StAR), cytochrome p450 side chain cleavage enzyme, 17α-hydroxylase/20-lysase,3β-hydroxysteroid dehydrogenase 1 and 2 and 17β-hydroxysteroid dehydrogenase 3, were maintained. This study demonstrated that purified rat progenitor, immature and adult Leydig cells can be frozen and that the cryopreserved cells retai

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Access to smart devices and utilization of online health resources among older cardiac rehabilitation participants

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World Journal of Cardiology 2020年第5期12卷 203-209页

作者： Abdulghani Saadi Arun Kanmanthareddy mahesh Anantha-Narayanan Karen hardy mark Williams Venkata m Alla Division of Cardiology Creighton University School of MedicineOmahaNE 68124United States CHI Creighton University Medical CenterOmahaNE 68124United States Section of Cardiovascular medicine Yale New Haven HospitalNew HavenCT 06510United States

BACKGROUND Newer models of cardiac rehabilitation(CR)delivery are promising but depend upon patient participation and ability to use technological media including Internet and smart *** To explore the availability of smart devices,current utilization and proficiency of use among older CR program *** Study participants were enrolled from four CR programs in Omaha,Nebraska United States and completed a questionnaire of 28 *** Of 376 participants approached,169 responded(45%).mean age was 71.1(SD±10)*** were 73.5%males,89.7%Caucasians,52%with college degree and 56.9%,with income of 40 K$or *** device ownership was84.5%;desktop computer was the most preferred *** Internet use was 1.9 h/d(SD±1.7);54.3%of participants indicating for general usage but only18.4%pursued health-related *** of other health information modalities was low,29.8%used mobile health applications and 12.5%used wearable *** all participants,72%reported no barriers to using *** and income were associated positively with measures of utilization and with less perceived *** an older group of subjects attending CR,most have access to smart devices and do not perceive significant barriers to Internet ***,there was low utilization of health-related resources suggesting a need for targeted education in this patient population.

关键词： Cardiac rehabilitation Smart devices Internet perceived barriers

Biophysics inspired artificial intelligence for colorectal cancer characterization

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Artificial Intelligence in Gastroenterology 2021年第3期2卷 77-84页

作者： Niall p hardy Jeffrey Dalli pól mac Aonghusa peter m Neary Ronan A Cahill UCD Centre for precision Surgery Dublin 7 D07 Y9AWIreland IBm Research IBM Research IrelandDublin 15 D15 HN66Ireland Department of Surgery University Hospital WaterfordUniversity College CorkWaterford X91 ER8EIreland Department of Surgery Mater Misericordiae University Hospital(MMUH)Dublin 7Ireland

Over the last ten years artificial intelligence(AI)methods have begun to pervade even the most common everyday tasks such as email filtering and mobile *** the necessary quality and safety standards may have understandably slowed the introduction of AI to healthcare when compared with other industries,we are now beginning to see AI methods becoming more available to the clinician in select *** this paper we discuss current AI methods as they pertain to gastrointestinal procedures including both gastroenterology and gastrointestinal *** current state of the art for polyp detection in gastroenterology is explored with a particular focus on deep leaning,its strengths,as well as some of the factors that may limit its application to the field of *** use of biophysics(utilizing physics to study and explain biological phenomena)in combination with more traditional machine learning is also discussed and proposed as an alternative approach that may solve some of the challenges associated with deep *** and present uses of biophysics inspired AI methods,such as the use of fluorescence guided surgery to aid in the characterization of colorectal lesions,are used to illustrate the role biophysicsinspired AI can play in the exciting future of the gastrointestinal proceduralist.

关键词： Gastroenterology Artificial intelligence Gastrointestinal surgery Deep learning Biophysics machine learning

Zinc Redistribution in a Soil Developed from Limestone During pedogenesis

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pedosphere 2009年第3期19卷 292-304页

作者： C. LAVEUF S. CORNU D. BAIZE m. hardy O. JOSIERE S. DROUIN A. BRUAND F. JUILLOT INRA UR0272 Science du Sol Centre de recherche d'Orlans 45075 Orlans cedex 2 (France) ISTO UMR 6113 CNRS Universit d'Orlans 45071 Orlans cedex 2 (France) ISTO UMR 6113 CNRS Universitd'Orlans 45071 Orlans cedex 2 (France) ImpmC UMR CNRS 7590 Universit Paris 6 et 7 IPGC 75252 Paris cedex 05 (France)

The long-term redistribution of Zn in a naturally Zn-enriched soil during pedogenesis was quantified based on mass balance calculations. According to their fate, parent limestones comprised three Zn pools: bound to calcite and pyritesphalerite grains, bound to phyllosilicates and bound to goethite in the inherited phosphate nodules. Four pedological processes, i.e., carbonate dissolution, two stages of redox processes and eluviation, redistributed Zn during pedogenesis. The carbonate dissolution of limestones released Zn bound to calcite into soil solution. Due to residual enrichment, Zn concentrations in the soil are higher than those in parent limestones. Birnessite, ferrihydrite and goethite dispersed in soil horizon trapped high quantities of Zn during their formation. Afterwards, primary redox conditions induced the release of Zn and Fe into soil solution, and the subsequent individualization of Fe and mn into Zn-rich concretions. Both processes and subsequent aging of the concretions formed induced significant exportation of Zn through the bottom water table. Secondary redox conditions promoted the weathering of Fe and mn oxides in cements and concretions. This process caused other losses of Zn through lateral exportation in an upper water table. Concomitantly, eluviation occurred at the top of the solum. The lateral exportation of eluviated minerals through the upper water table limited illuviation. Eluviation was also responsible for Zn loss, but this Zn bound to phyllosilicates was not bioavailable.

关键词： carbonate dissolution eluviation long-term redox speciation

Fatigue Response of Cold-Rolled Type-304 Stainless Steel Foil

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Journal of minerals and materials Characterization and Engineering 2021年第1期9卷 90-99页

作者： Thomas p. Kieffer James I. hardy micro-measurements Vishay Precision Group Wendell USA

This study presents the fatigue response of 304 stainless steel foil, cold-rolled to a thickness of 3.2 μm with 87 percent cold work at orientations of 0, 45, and 90 degrees to the direction of rolling. Fatigue specimens were fabricated by laminating a supportive layer of 20-μm polyimide film to one side of the foil and patterning 242 crack initiation features by photolithographic process. progression of fatigue damage was determined through electrical resistance measurement. The fatigue response was demonstrated to be largely affected by anisotropy existing between the rolling direction and the off-axis orientations. Fatigue cracks that traveled in a direction parallel to the elongated grains (cyclic loads applied at 90-degree orientation to foil rolling direction) had the most fatigue response (undesirable characteristic). The construction of the specimens with thin foil supported by a film backing contributed to high fatigue threshold.

关键词： Fatigue Cold-Rolled Foil Type-304 Stainless Steel Resistive-Sensing Anisotropy