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First mushroom-shaped adhesive microstructure:A review

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Theoretical & Applied Mechanics Letters 2012年第1期2卷 40-43页

作者： L.Heepe A.E.Kovalev M.Varenberg J.Tuma S.N.Gorb Department of Functional morphology and Biomechanics Zoological Institute of the University of Kiel Department of Mechanical Engineering Technion-IIT Gottlieb Binder GmbH Bahnhofstrasse 19 Holzgerlingen 71088Germany

This letter reviews the adhesive and frictional properties of the first mushroom-shaped adhesive microstructure （MSAMS）, which has come a long way from inspiration by the attachment devices evolved in beetles to a large-scale industrial production. It was shown to have an that about twice higher pull-off force compared to a smooth control made from the same material measured on smooth substrates. Pull-off forces measured underwater are even higher than those in air. Moreover, it retained adhesive performance over thousands of attachment cycles and initial adhesive capability could be recovered by washing after being contaminated. In shearing, MSAMS exhibits reduced and stabilized friction in comparison with a smooth control, which demonstrated pronounced stick-slip motion, and shows zero pull-off force in a sheared state, allowing the adhesion to be switched on and off. The presence of a fluid in the contact zone showed adhesion enhancement on both smooth and rough substrates. All these features lead us to conclude that MSAMS may have practical potential in a variety of applications.

关键词： adhesion friction gecko bio-inspired biomimetics polymer contact mechanics

Expression and Localization of NANOS1 in Spermatogenic Cells during Spermatogenesis in Rat

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CellBio 2013年第1期2卷 1-10页

作者： Sadaki Yokota Yuko Onohara Section of Functional morphology Faculty of Pharmaceutical Sciences Nagasaki International University Nagasaki Japan

Expression and localization of NANOS1 in the spermatogenic cells of rat testis were studied by immunofluorescence and immunoelectron microscopy. Using immunofluorescence techniques, NANOS1 was localized in the cytoplasm and discrete granules of spermatocytes and spermatids. The staining intensity of NANOS1 signal varied depending upon the stage of the cycle of seminiferous epithelium. Double immunofluorescence staining with antibodies against NANOS1 and DDX4 showed that several DDX4-positive compartments of nuage were also stained for NONOS1. Immunoelectron microscopy revealed that the major subcellular localization sites for NANOS1 were the chromatoid body (CB) and satellite body (SB), and the minor sites were the rest of the nuage compartments, including the irregularly-shaped perinuclear granules (ISPG), and intermitochondrial cement (IMC). Non-nuage structures such as mitochondria-associated granules (MAG), granulated body (GB), and reticulated body (RB) were also labeled by theNANOS1 antibody. In addition, NANOS1 was found in the outer dense fibers of flagella of spermatids at steps 12-19, and in the head cap of late spermatids after step 15. These results suggest that NANOS1 is one of the nuage proteins and functions mainly in the CBs as well as in the cytoplasm. NANOS1 may also have additional functions in non-nuage structures such as MAGs, GBs and RBs.

关键词： NANOS1 Nuage Chromatoid Body Satellite Body Non-Nuage Compartments Immunocytochemistry

Seminal concentrations of trace elements in various animalsand their correlations

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Asian Journal of Andrology 2003年第2期5卷 101-104页

作者： P.Massányi J.Trandzik P.Nad R.Toman M.Skalická B.Koréneková Department of Animal morphology Slovak University of Agriculture SK-94976 Nitra Slovak Republic State Breeding Institute SK-94992 Nitra Slovak Republic Research Institute of Veterinary Medicine University of Veterinary Medicine SK-040 01 Kosice Slovak Republic

Aim: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and analyzed by means of the atomic absorption spectrophotometer. Data were analyzed statistically with the Student's t-test and Scheffe's test using PC programs SAS and Excel. Results: The seminal copper concentration was significantly higher in ram [(2.49±0.18) mg/kg] and fox [(2.16±0.53) mg/kg] than that in bull [(1.64±0.21) mg/kg], boar [(1.64±0.28) mg/kg] and stallion (0.86 mg/kg). In boar a significantly higher seminal zinc concentration (171.74±65.72) mg/kg] was found in comparison with stallion [(86.20±45.88) mg/kg], bull [(83.15±61.61) mg/kg], ram [( 60.46±35.37) mg/kg] and fox (13.09±5.22) mg/kg]. The iron concentration in semen was significantly higher in ram [(40.32±10.81) mg/kg), bull [(38.04±22.07) mg/kg] and fox [(33.16±24.36) mg/kg] than that in boar [(16.14±10.35) mg/kg] and stallion (12.68 mg/kg). The seminal cadmium concentration was relatively low [(0.05-0.12) mg/kg] in all studied species. The seminal lead concentration was the highest in ram [(0.35±0.68) mg/kg], which was much higher than in fox [(0.08±0.06) mg/kg], bull [(0.06±0.04) mg/kg], stallion [(0.05±0.05) mg/kg] and boar [0.02±0.03) mg/kg]. The level of seminal nickel was significantly higher in fox [(0.35±0.24) mg/kg] and ram [(0.31±0.19) mg/ kg] in comparison with bull [(0.12±0.07) mg/kg] and boar [(0.06±0.08) mg/kg]. The concentration of nickel in the semen of stallion was (0.20±0.24) mg/kg. There was a high positive correlation between seminal iron and zinc in bull (r=0.723) and stallion (r=0.723), between cadmium and lead in ram (r=0.976) and boar (r=0.973) and between iron and cadmium (r=0.783) and iron and lead (r=0.791) in boar. A high negative correlation between seminal nickel and copper in ram (r=-0.709) and between seminal copper and lead in fox (r=-0.854) was found

关键词： semen copper zinc iron cadmium lead nickel

The Role of Vanes in the Damping of Bird Feathers

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Journal of Bionic Engineering 2023年第4期20卷 1646-1655页

作者： Kai Deng Hamed Rajabi Alexander Kovalev Clemens F.Schaber Zhendong Dai Stanislav N.Gorb Functional morphology and Biomechanics Institute of ZoologyKiel University24098KielGermany School of Engineering London South Bank UniversityLondonSE10AAUK Institute of Bioinspired Structure and Surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing210026People’s Republic of China

Bird feathers sustain bending and vibrations during *** unwanted vibrations could potentially cause noise and flight *** could alter the system response,resulting in improving quiet flight,stability,and *** of feathers are known to be indispensable for supporting the aerodynamic function of the *** relationship between the hierarchical structures of vanes and the mechanical properties of the feather has been previously ***,still little is known about their relationship with feathers’damping ***,the role of vanes in feathers’damping properties was *** vibrations of the feathers with vanes and the bare shaft without vanes after step deflections in the plane of the vanes and perpendicular to it were measured using high-speed video *** presence of several main natural vibration modes was observed in the feathers with *** trimming vanes,more vibration modes were observed,the fundamental frequencies increased by 51-70%,and the damping ratio decreased by 38-60%.Therefore,we suggest that vanes largely increase feather damping *** mechanisms based on the morphology of feather vanes are *** aerodynamic damping is connected with the planar vane surface,the structural damping is related to the interlocking between barbules and barbs,and the material damping is caused by the foamy medulla inside barbs.

关键词： Bird Feather Vibrations Damping Bionic

Precise tissue bioengineering and niches of mesenchymal stem cells:Their size and hierarchy matter

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BIOCELL 2022年第6期46卷 1365-1373页

作者： IGOR A.KHLUSOV LARISA S.LITVINOVA KRISTINA A.YUROVA MARINA Y.KHLUSOVA Department of morphology and General Pathology Siberian State Medical UniversityTomsk634050Russia Center for Immunology and Cell Biotechnology Immanuel Kant Baltic Federal UniversityKaliningrad236029Russia Department of Pathophysiology Siberian State Medical UniversityTomsk634050Russia

Stem cell microterritories(niches),as a specialized part of the extracellular matrix(ECM),are considered an important target and tool for the development of new materials,medical implants,and ***,tissue bioengineering products that have stem cell niches of known size on the surface or in the bulk structure of artificial materials are practically *** brief review attempts to draw attention to the problematic aspects of niches as specific parts of the ECM,such as their hierarchy and size for mesenchymal stromal/stem cells(MSCs).These parameters arise directly from numerous definitions of stem cell niches as specialized morphological microterritories found in various *** authors of this review analyze the known information on the hierarchy of MSC microterritories by analogy with that of hematopoietic stem *** reports on the size of artificial MSC niches compared to natural niche candidates are summarized.A consensus on a hierarchy and optimal range of niche sizes for MSCs and other stem cells is needed to accelerate the development of prototyping technologies and additive manufacturing in applications to precise tissue bioengineering and regenerative medicine.

关键词： Mesenchymal stromal/stem cells Natural and artificial niches Classification Dimension Matrix features Usefulness

Serum levels of angiotensin converting enzyme as a biomarker of liver fibrosis

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World Journal of Gastroenterology 2017年第48期23卷 8439-8442页

作者： Aline Silva Miranda Ana Cristina Sim?es e Silva In-terdisciplinary Laboratory of Medical Investigation Faculty of MedicineFederal University of Minas Gerais Laboratory of Neurobiology Department of MorphologyInstitute of Biological SciencesFederal University of Minas Gerais Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais

The renin angiotensin system(RAS) is classically conceived as a circulating hormonal system involved in blood pressure control and hydroelectrolyte balance. The discovery that RAS components are locally expressed in a wide range of organs and tissues,including the liver,pointed to a role for this system in the pathogenesis of several conditions including hepatic fibrosis and cirrhosis. It has been widely reported that the classical RAS axis composed by the angiotensin converting enzyme(ACE)-angiotensin(Ang) Ⅱ-Ang type 1(AT1) receptor mediates pro-inflammatory,pro-thrombotic,and pro-fibrotic processes. On the other hand,the alternative axis comprising ACE2-Ang-(1-7)-Mas receptor seems to play a protective role by frequently opposing Ang Ⅱ action. Chronic hepatitis B(CHB) is one of the leading causes of liver fibrosis,accounting for the death of nearly one million people worldwide. Liver fibrosis is a key factor to determine therapeutic interventions for patients with CHB. However,the establishment of non-invasive and accurate methods to detect reversible stages of liver fibrosis is still a challenge. In an elegant study published in the 36 th issue of the World Journal of Gastroenterology,Noguchi et al showed the predictive value of serum ACE levels in detecting not only advanced stages of liver fibrosis but also initial and intermediate fibrotic stages. The serum levels of ACE might represent an accurate,non-invasive,widely available,and easy method to evaluate fibrosis related to CHB. Moreover,therapies involving the inhibition of the classical RAS axis components might be promising in the control of CHB-related liver fibrosis.

关键词： Renin angiotensin system Angiotensin converting enzyme Angiotensin Ⅱ Angiotensin-(1-7) Chronic hepatitis B hepatic cirrhosis Liver fibrosis

Post-coital death in chronic sildenafil abuser

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Journal of Geriatric Cardiology 2020年第3期17卷 169-172页

作者： Stefano D'Errico Diana Bonuccelli Margherita Neri Department of Medicine Surgery and HealthUniversity of TriesteItaly Department of Legal Medicine Azienda USL Toscana NordovestLuccaItaly Department of morphology Experimental Medicine and SurgerySection of Legal Medicine and LTTA CentreUniversity of FerraraFerraraItaly

Sex-related cardiovascular arrest is a rare event occurring typically among middle-aged men with cardiovascular risk.[1,2]The main etiologies of sex-related sudden cardiovascular arrest are acute coronary syndrome and subarachnoid hemorrhage and,to a lesser extent,chronic coronary artery disease and structural non-ischemic heart disease.[3]Coital angina that occurs during the minutes or hours after sexual activity represents<5%of all anginal attacks and it is rare in patients who do not have angina during strenous physical exertion.[4]Moreover,sexual activity is the cause of<1%of all acute myocardial infarctions.[5]Sudden death during sexual intercourse is reported with an incidence of 0.6%–1.7%.[6–8]The investigation of sudden death related to sexual activity may be difficult as it may be regarded as shameful or disgraceful to the family members and,especially to the remaining *** of rarity of epidemiological data,considerable bias in the investigation of sudden death related to sexual activity has to be expected.[9–11]Extramarital sexual activity with younger partner and unfamiliar setting seems to represent risk factor as well as excessive food and alcohol consumption.[7]

关键词： Cardiovascular events Sex Sildenafil Sudden death

Tamarix chinensis Lour inhibits chronic ethanol-induced liver injury in mice

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World Journal of Gastroenterology 2020年第12期26卷 1286-1297页

作者： Zhi-Dan Wang Yu Zhang Yi-Dan Dai Ke Ren Chen Han Heng-Xiao Wang Shuang-Qin Yi Laboratory of Functional morphology Graduate School of Human Health SciencesTokyo Metropolitan UniversityTokyo 116-8551Japan Institute of Basic Medicine Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250062Shandong ProvinceChina

BACKGROUND Tamarix chinensis Lour(TCL)is a shrub that usually grows in arid or semiarid desert areas and saline-alkali *** is a traditional Chinese herbal medicine with hepatoprotective,antioxidant,antibacterial,and antitumor *** To investigate the possible protective effects of TCL against liver injury induced by chronic ethanol *** C57BL/6J male mice were fed a Lieber-DeCarli lipid diet containing alcohol and received(by gavage)a water-alcohol extract(80%)of TCL(100 and 200 mg/kg BW)or distilled water for 4 *** euthanasia,liver tissues were observed histologically with hematoxylin and eosin staining and Oil red O staining,and the levels of alanine aminotransferase,aspartate transaminase,hepatic lipids,reactive oxygen species,malondialdehyde,and superoxide dismutase were *** addition,expression of the NOD-like receptor family,pyrin domain-containing 3(NLRP3)inflammasome and downstream proinflammatory cytokines were *** Compared with the ethanol group,mice in the TCL-treated group(200 mg/kg)had significantly lower serum levels of alanine aminotransferase(mean,34.1 IU/L vs 45.3 IU/L,P<0.01)and aspartate transaminase(mean,89.6 IU/L vs 115.7 IU/L,P<0.01),as well as marked reduction of hepatic tissue reactive oxygen species(decreased by 27.5%,P<0.01)and malondialdehyde(decreased by 76.6%,P<0.01)levels,with a significant increase of superoxide dismutase(Increased by 73.2%,P<0.01).Expression of the NLRP3 inflammasome and its downstream cytokines[interleukin(IL)-1β,tumor necrosis factor-α,and IL-6],and recruitment of natural killer T cells to the liver,were reduced in the TCLtreated incubation with a Lieber-DeCaril ethanol lipid diet *** These findings suggest that a TCL extract(200 mg/kg)protects against chronic ethanol-induced liver injury,probably by inhibiting the NLRP3-caspase-1-IL-1βsignaling pathway and suppressing oxidative stress.

关键词： Tamarix chinensis Lour Alcoholic liver disease Ethanol-induced liver injury NLRP3 inflammasome Oxidative stress Natural killer T cells

Sub-chronic effects of a Phthirusa pyrifolia aqueous extract on reproductive function and comparative hormone levels in male rats

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Asian Pacific Journal of Tropical Biomedicine 2016年第3期6卷 202-210页

作者： Romero Marcos Pedrosa Brandao-Costa Vivianne Ferreira Araujo Elizabeth Neves Maria Tereza Santos Correia Ana Lucia Figueiredo Porto Maria das Gracas Carneiro-da-Cunha Department of Biochemistry Center of Biological Sciences Federal University of Pernambuco Keizo Asami Laboratory of Imunopathology LIKA/UFPE Department of Anatomy Federal University of Pernambuco Department of Animal morphology and Physiology Federal Rural University of Pernambuco Keizo Asami Laboratory of Imunopathology LIKA/UFPE

Objective: To explore the effects of aqueous extract from Phthirusa pyrifolia leaves(67 mg/kg body weight for 12 days) on the reproductive function of male Wistar rats through oral ***: Animals(n = 30), aged 13 weeks and weighing(378.5 ± 5.0) g, were housed in a vivarium under controlled environmental conditions [photoperiod of 12 h light/dark,temperature of(23 ± 1)C] and were fed standard rations ad libitum. The experiment ran for 12 days, wherein animals were divided into three groups: negative control(n = 6)received water, positive control(n = 12) with finasteride at a concentration of 1.0 mg/kg;and a test group(n = 12) submitted to aqueous extract. At the end of the experiment, the animals were sacrificed and submitted to ***: The morphological results of the testes showed that the aqueous extract induced significant changes in the diameter and cross-sectional area of the seminiferous tubules as well as the thickness of the seminiferous epithelium. Furthermore, the extract was able to abruptly decrease testosterone concentrations by about 81.88% in the treated group when compared with the negative control,(47.0 ± 4.8) ng/d L and(255.0 ± 2.0) ng/d L,respectively, and 76.8%,(211.0 ± 8.7) ng/d L, when compared with finasteride. However,the extract causes neither liver damage nor impairment of renal ***: These results suggest that the high amounts of flavonoids shown to be in the extract may be responsible for its hepato-protective effects and suggest a possible decrease in the libido and reproduction of rats.

关键词： Reproductive function Phytochemical Testosterone Finasteride Phthirusa pyrifolia