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Vitamin B12-induced spermatogenesis recovery in cimetidine-treated rats： effect on the spermatogonia number and sperm concentration

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Asian Journal of Andrology 2017年第5期19卷 567-572页

作者： Flavia L Beltrame Estela Sasso-Cerri Department of morphology and Genetics Federal University of Sao Paulo (UNIFESP/EPM) Sao Paulo Brazil Department of morphology Laboratory f Histology and Embryology Dental School - Sao Paulo State University (UNESP/FOAr) Araraquara Sao Paulo Brazil

The H2-receptor antagonist cimetidine is an antiulcer drug also used for the treatment of cancer due to its antiangiogenic effect. However, this drug has caused structural changes in the seminiferous tubules. Vitamin B12 has been used as a therapeutic agent for the treatment of male infertility. The supplementation of rats with vitamin B12 during cimetidine treatment has recovered the damaged seminiferous tubules, but how this vitamin restores the seminiferous epithelium has not been clarified. In this study, we evaluated whether vitamin B12 improves the number of spermatogonia, spermatocytes, and sperm concentration in cimetidine-treated rats. Adult male rats were treated for 50 days as follows： cimetidine group received 100 mg kg^-1 b.w. of cimetidine, cimetidine-B12 group received cimetidine and 3 μg of vitamin B12-hydroxocobalamin, B12 group received only 3 μg of vitamin, and control group received saline. Sperm concentration was calculated and historesin-embedded testes sections were used for the quantitative analyses of spermatogonia （A; In/B） and spermatocytes. TUNEL method and PCNA immunofluorescence were performed. Cimetidine caused a significant reduction in sperm concentration. TUNEL-positive spermatogonia and spermatocytes were correlated to a significant reduction in the number of these cells. In cimetidine-B12 group, sperm concentration was higher than cimetidine group and a significant increase in the number of spermatogonia （stages Ⅱ-Ⅵ） was correlated to a high incidence of PCNA-immunolabeled spermatogonia and spermatocytes. The results show that the supplementation of rats with vitamin B12 during cimetidine treatment increases sperm concentration and exerts a potential effect in the recovery of spermatogonia and spermatocytes.

关键词： cimetidine fertility spermatogenesis testis vitamin B12

Electron probe microanalysis оf experimentally stimulated osteoarthrosis in dogs

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World Journal of Orthopedics 2017年第9期8卷 681-687页

作者： Tatyana Stupina Michael Shchudlo Michael Stepanov Laboratory of morphology FSBI Russian Ilizarov Scientific Center "Restorative Traumatology and Orthopaedics"

AIM To develop methods of articular cartilage preparation for X-ray-electron probe microanalysis and to study its elements content in experimental *** Twenty dogs aged 2-8 years were divided in research(aged 2 years, induction of osteoarthrosis-IOA) and intact group. Intact group included three subgroups(aged 2, 5 and 8 years). Samples of cartilage after araldite saturation and pouring were partially cut into semithin sections stained with methylene blue and with methylene blue-basic fuchsin. Their smooth surfaces were investigated by X-ray-electron probe microanalysis. Spatial distribution of sulfur, calcium and phosphorus and their concentrations(weight %) were *** X-ray electron probe microanalysis revealed non-uniformsulfur distribution in cartilage of intact animals: Its content increases from superficial zone to deep one, this regularity was preserved in animals with IOA. Differences of IOA with spontaneous chondropathy were revealed. Spontaneous aging was characterized by calcium and phosphorus storage in deep and calcified zones and compensatory increase of sulfated glycosaminoglycans in intermediate and deep cartilage zones as evidenced by the metachromatic reaction and microanalysis data. Unlike spontaneous chondropathy connected with aging in experimentally stimulated osteoarthrosis more intensive storage of calcium but minor phosphorus in intermediate zone were marked. In IOA the calcified cartilage thinning and osteoclastic resorption are apparent with few changes of elements composition; the only difference from control is minority phosphorus *** The obtained results demonstrate specific tricks of X-ray electron probe microanalysis and its possibility in the research of mechanisms of articular cartilage alterations in osteoarthrosis.

关键词： Osteoarthrosis Articular cartilage Dog X-ray electron probe microanalysis

Benefits of Ilizarov automated bone distraction for nerves and articular cartilage in experimental leg lengthening

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World Journal of Orthopedics 2017年第9期8卷 688-696页

作者： Nathalia Shchudlo Tatyana Varsegova Tatyana Stupina Michael Shchudlo Marat Saifutdinov Andrey Yemanov Laboratory of morphology FSBI Russian Ilizarov Scientific Center "Restorative Traumatology and Orthopaedics"

AIM To determine peculiarities of tissue responses to manual and automated Ilizarov bone distraction in nerves and articular *** Twenty-nine dogs were divided in two experimental groups: group M-leg lengthening with manual distraction(1 mm/d in 4 steps), group A-automated distraction(1 mm/d in 60 steps) and intact group. Animals were euthanized at the end of distraction, at 30 th day of fixation in apparatus and 30 d after the fixator removal. M-responses in gastrocnemius and tibialis anterior muscles were recorded, numerical histology of peronealand tibialis nerves and knee cartilage semi-thin sections, scanning electron microscopy and X-ray electron probe microanalysis were *** Better restoration of M-response amplitudes in leg muscles was noted in A-group. Fibrosis of epineurium with adipocytes loss in peroneal nerve, subperineurial edema and fibrosis of endoneurium in some fascicles of both nerves were noted only in M-group, shares of nerve fibers with atrophic and degenerative changes were bigger in M-group than in A-group. At the end of experiment morphometric parameters of nerve fibers in peroneal nerve were comparable with intact nerve only in A-group. Quantitative parameters of articular cartilage(thickness, volumetric densities of chondrocytes, percentages of isogenic clusters and empty cellular lacunas, contents of sulfur and calcium) were badly changed in M-group and less changed in *** Automated Ilizarov distraction is more safe method of orthopedic leg lengthening than manual distraction in points of nervous fibers survival and articular cartilage arthrotic changes.

关键词： Limb lengthening Articular cartilage Nerve Histomorphometry Dog

Molecular Cloning and Functional Characterization of Porcine MyD88 Essential for TLR Signaling

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Cellular & Molecular Immunology 2007年第5期4卷 369-376页

作者： Masanori Tohno Tomoyuki Shimazu Hisashi Aso Yasushi Kawai Tadao Saito Haruki Kitazawa Food Immunology group Laboratory of Animal Products ChemistryGraduate School of Agricultural ScienceTohoku UniversityAobakuSendai 981-8555Japan Research Fellow of the Japan Society for the Promotion of Science Food Immunology group Laboratory of Animal Products ChemistryGraduate School of Agricultural ScienceTohoku UniversityAobakuSendai 981-8555Japan Laboratory of Functional morphology Graduate School of Agricultural ScienceTohoku UniversityAobakuSendai 981-8555Japan

We isolated cDNA encoding porcine MyD88 （poMyD88） from Peyer＇s patches （Pps） of GALT. The complete open reading frame （ORF） of poMyD88 contains 879 bp encoding a deduced 293 aa residues. The amino acid sequence of poMyD88 was characterized by N-terminal death, intermediate and C-terminal Toll/IL-1 receptor （TIR） domains. The putative poMyD88 protein shares a higher level of homology with its human （87.2% amino acid identity） than with its mouse （77.4% amino acid identity） counterpart. Overexpression of poMyD88 participated in the further enhanced activation of NF-w.B in human embryonic kidney （HEK） 293 cells expressing porcine TLR2 and porcine TLR4/MD-2, but not porcine RP105/MD-1 after stimulation with the corresponding ligands. The expression levels of MyD88 were highest in the spleen and mesenteric lymph nodes （MLNs）, and lower in digestive tissues of newborn swine. In adult swine, the expression levels in the digestive tissues were lower than those in MLNs and the spleen. These results suggest that an MyD88-dependent signaling pathway is present in newborn as well as in adult swine and that it is involved in the innate immune system of these animals.

关键词： MyD88 TLR2 TLR4/MD-2 RP105/MD-1 cDNA cloning swine

Toxin variation among salamander populations:discussing potential causes and future directions

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Integrative Zoology 2021年第3期16卷 336-353页

作者： Gilles DE MEESTER EminaŠUNJE Els PRINSEN Erik VERBRUGGEN Raoul VANDAMME Department of Biology Functional Morphology GroupUniversity of AntwerpWilrijkBelgium Department of Biology Faculty of Natural SciencesUniversity of SarajevoSarajevoBosnia-Hercegovina Herpetological Association in Bosnia and Herzegovina:BHHU:ATRA SarajevoBosnia-Hercegovina Department of Biology ImpressUniversity of AntwerpWilrijkBelgium Department of Biology Plant and EcosystemsUniversity of AntwerpWilrijkBelgium

Amphibians produce defensive chemicals which provide protection against both predators and *** species,populations can differ considerably in the composition and amount of these chemical *** intraspecific variation in toxins and linking it to environmental variables may help us to identify the selective drivers of toxin evolution,such as predation pressure and infection ***,there has been a renewed interest in the unique toxins produced by salamanders from the genus Salamandra:the *** this attention,intraspecific variation has largely been ignored within *** aim of this study was to investigate whether geographic variation in profiles of samandarines exists,by sampling 4 populations of Salamandra atra over its range in the Dinaric *** addition,we preliminary explored whether potential variation could be explained by predation(counting the number of snake species)and infection risk(cultivation and genomic analyses of collected soil samples).Salamanders from the 4 populations differed in toxin composition and in the size of their poison glands,although not in overall toxin *** predation nor infection risk could explain this variation,as populations barely differed in these *** over a much broader geographic range,using better estimators for predation and infection risk,will contribute to an improved understanding of how environment may shape variation in chemical ***,as the 4 populations of *** did differ in their toxin profiles,we propose that this species provides an interesting opportunity for further ecological and evolutionary studies on amphibian toxins.

关键词： amphibian toxins geographic variation poison glands Salamandra atra samandarines

Genome differentiation in Magonoliaceae as revealed from meiotic pairing in interspecific and intergeneric hybrids

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Journal of Systematics and Evolution 2011年第6期49卷 518-527页

作者： Erland EJDER University of Lund and Swedish Magnolia group

The cross compatibility within and between Yulania Spach and Michelia L.(Magnoliaceae) is relatively good and various such hybrids,obtained by conventional artificial hybridization,are *** aim of the present study was to determine the extent of genome differentiation between the species involved in these crosses through the observation of chromosome pairing during meiosis in pollen mother cells(PMCs) of the *** pairing behavior was studied in five species(2n = 38) and two interspecific hybrids of Michelia,eight species(2n = 38,76 and 114) and 10 interspecific hybrids of Yulania,and three intergeneric hybrids between Michelia and *** results showed that chromosome pairing was normal with bivalent formation in diploid parental species and in interspecific *** addition to bivalents,multivalents were encountered in polyploid parental species and polyploid interspecific *** the intergeneric hybrids between a tetraploid Yulania and two diploid Michelia,19 chromosomes,most likely originating from Michelia,were unable to synapse from zygotene to metaphase *** chromosome pairing indicated a high degree of homology between species within Michelia and Yulania and less homology between the genomes of these two *** differentiation of morphological characters and the distinctness of natural distribution also support the conclusion that these two genera are likely independent monophyletic *** suggests that the two genera were split at early evolution of Magnoliaceae and the overlapping characteristics in external morphology and internal structures of the two genera may be the result of parallel evolution or ancient common ancestry.

关键词： intergeneric hybrids interspecific hybrids Magnoliaceae meiotic behavior Michelia Yulania.

Platelet-rich plasma for regeneration of neural feedback pathways around dental implants: a concise review and outlook on future possibilities

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International Journal of Oral Science 2017年第1期9卷 1-9页

作者： Yan Huang Michael M Bornstein Ivo Lambrichts Hai-Yang Yu Constantinus Politis Reinhilde Jacobs OMFS IMPATH Research group Department of Imaging and PathologyFaculty of MedicineKU Leuven and Oral and Maxillofacial SurgeryUniversity Hospitals Leuven State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan University Section of Dental Radiology and Stomatology Department of Oral Surgery and StomatologyUniversity of Bern Applied Oral Sciences Faculty of DentistryThe University of Hong KongPrince Philip Dental Hospital group of morphology Biomedical Research InstituteHasselt University

Along with the development of new materials, advanced medical imaging and surgical techniques, osseointegrated dental implants are considered a successful and constantly evolving treatment modality for the replacement of missing teeth in patients with complete or partial edentulism. The importance of restoring the peripheral neural feedback pathway and thus repairing the lack of periodontal rnechanoreceptors after tooth extraction has been highlighted in the literature. Nevertheless, regenerating the nerve fibers and reconstructing the neural feedback pathways around osseointegrated implants remain a challenge. Recent studies have provided evidence that platelet-rich plasma （PRP） therapy is a promising treatment for musculoskeletal injuries. Because of its high biological safety, convenience and usability, PRP therapy has gradually gained popularity in the clinical field Although much remains to be learned, the growth factors from PRP might play key roles in peripheral nerve repair mechanisms. This review presents known growth factors contributing to the biological efficacy of PRP and illustrates basic and （pre-）clinical evidence regarding the use of PRP and its relevant products in peripheral nerve regeneration. In addition, the potential of local application of PRP for structural and functional recovery of iniured peripheral nerves around dental implants is discussed.

关键词： neural regeneration osseoperception peripheral nerve degeneration peri-implant sensory feedback platelet-rich plasma

A Comparative Study on the Corrosion Behaviour of Hard Anodic Coatings on AA 6061 Obtained Using DC and Pulsed DC Power Sources

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 647-656页

作者： Franco M. Hari Krishna T. Anju M.Pillai A.Rajendra A.K.Sharma Thermal Systems group ISRO Satellite Centre

The corrosion behaviour of the hard anodic coatings prepared by three different methods viz., conventional hard anodizing （C-HA）, pulse hard anodizing （P-HA） and low voltage room temperature pulse hard anodizing （LVP- HA） on AA 6061 was compared using electrochemical impedance spectroscopy （EIS） and linear polarisation. Scanning electron microscope （SEM） was used to study the surface morphology before and after corrosion. EIS data revealed that no significant difference in corrosion resistance was observed among three types. Rp, Icorr and Ecorr were found to be highly stable over the exposure period up to 72 h which confirms the excellent corrosion resistance. The studies indicate that the corrosion resistance of LVP-HA and P-HA, which are processed at lower voltage and at relatively higher temperatures, are comparable to that of C-HA which is processed at sub-zero temperatures and high operating voltages. The corrosion resistance of all coatings was found to be improved after hydrothermal sealing.

关键词： Aluminium Anodic films EIS Polarisation SEM

Wear and Friction Properties of Electrodeposited Ni-Based Coatings Subject to Nano-enhanced Lubricant and Composite Coating

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 902-910页

作者： Rizwan Bajwa Zulfiqar Khan H.Nazir Vivek Chacko Adil Saeed NanoCorr Energy and Modelling Research GroupBournemouth University

This paper presents research findings on the tribological performance of electrodeposited coatings subject to nano-lubricants with the addition of nano-Al2O3 and graphene and Ni/nano-Al2O3 composite coatings. Electrodeposited coatings were produced by using a pulse electrodeposition method. Tribological experiments were conducted by using a linear reciprocating ball on fiat sliding tribometer. Experimental results confirmed that the wear and friction resistance properties were significantly enhanced by doping of nano-effects in the lubricating oil and composite coating. The addition of Al2O3 nanoparticles in the lubricating oil showed the best tribological properties, followed by Ni-Al2O3 composite coatings and nano-oil with graphene. The surface morphology and microstructure of electrodeposited coatings were examined by scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction. The wear mechanisms of these coatings subjected to tribological testing were investigated by post-test surface analyses. This research provides a novel approach to design durable nano-coatings for tribological applications in various industries such as automotive, aerospace, locomotive and renewable energy technologies.

关键词： Tribology Nanoparticles Graphene Nano-additives Nano-coatings