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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

New exotic charmonium states

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Chinese Physics C 2010年第9期34卷 1157-1162页

作者： M.Nielsen Instituto de Física Universidade de So Paulo

In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the stru... 详细信息

关键词： non-perturbative methods heavy mesons spectroscopy exotic mesons

Helicobacter pylori and EBV in gastric carcinomas:Methylation status and microsatellite instability

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World Journal of Gastroenterology 2010年第3期16卷 312-319页

作者： Adriana Camargo Ferrasi Nídia Alice Pinheiro Silvia Helena Barem Rabenhorst Otávia Luisa Caballero Maria Aparecida Marchesan Rodrigues Fabrício de Carvalho Celso Vieira de Souza Leite Marcia Valéria Pitombeira Ferreira Marcos Aurélio Pessoa Barros Maria Inês de Moura Campos Pardini Blood Transfusion Center Botucatu Medical SchoolUNESP-Sao Paulo State University Department of Pathology-Federal University of Ceara Ludwig Institute of Cancer Research Department of Pathology Medical SchoolUNESP-Sao Paulo State University Department of Gastroenterology Surgery Medical SchoolUNESP-Sao Paulo State University

AIM:To verify the methylation status of CDH1, DAPK, COX2, hMLH1 and CDKN2A genes and to evaluate their association with Helicobacter pylori (H. pylori)-cagA+ and Epstein Barr virus (EBV) infections in gastric ***: Methylation-specific PCR (MSP) assay was performed in 89 primary gastric carcinomas (intestinal and diffuse types). Microsatellite instability (MSI) analysis was performed using the BAT26 primer set and PCR products were analyzed with the ABI PRISM 3100 Genetic Analyzer using Genescan 3.7 software (Applied Biosystems). Detection of H. pylori and genotyping were performed by PCR, using specifi c primers for ureaseC and cagA genes. The presence of EBV was assessed by in situ hybridization. Statistical analyses were performed using the χ2 or Fisher's exact ***: The most frequent hypermethylated gene was COX-2 (63.5%) followed by DAPK (55.7%), CDH1 (51%), CDKN2A (36%) and hMLH1 (30.3%). Intestinal and diffuse adenocarcinomas showed different methylation profiles and there was an association between methylation of E-CDH1 and H. pylori-cagA+ in the intestinal adenocarcinoma type. MSI was correlated with hMLH1 methylation. There was an inverse correlation between DAPK hypermethylation and ***: We found a strong association between CDH1 methylation and H. pylori-cagA+ in intestinal-type gastric cancer, association of MSI and better prognosis and an heterogeneous COX-2 overexpression.

关键词： Gastric cancer Methylation Microsatellite instability Helicobacter pylori Epstein Barr virus

Growth mechanism of octahedron-like BaMoO_4 microcrystals processed in microwave-hydrothermal:Experimental observations and computational modeling

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Particuology 2009年第5期7卷 353-362页

作者： Laécio Santos Cavalcante Júlio César Sczancoski Rircado Luis Tranquilin José Arana Varela Elson Longo Marcelo Ornaghi Orlandi Departamento de Química UFSCarP.O. Box 67613565-905So CarlosSPBrazil Instituto de Química-UNESP P.O. Box 35514801-907AraraquaraSPBrazil

Octahedron-like BaMoO4 microcrystals were synthesized by the co-precipitation method at room temperature and processed in microwave-hydrothermal at 413 K for different times （from 30 min to 5 h）. These microcrystals were analyzed by X-ray diffraction （XRD）, field-emission gun scanning electron microscopy （FEG-SEM） and transmission electron microscopy （TEM）. XRD patterns showed that this material presents a tetragonal structure without the presence of deleterious phases. FEG-SEM and TEM micrographs revealed that the BaMoO4 microcrystals present an octahedron-like morphology with agglomerate nature and polydisperse particle size distribution. These micrographs also indicated that the microcrystals grow along the [0 01 ] direction. The observed crystallographic planes in these structures were modeled computationally and a crystal growth model was proposed in order to explain the morphological changes as a function of processing time.

关键词： BaMoO4 Growth process Microwave-hydrotherma Supersaturated solution

Supergiant Barocaloric Effects in Acetoxy Silicone Rubber over a Wide Temperature Range:Great Potential for Solid-state Cooling

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Chinese Journal of Polymer Science 2020年第9期38卷 999-1005,I0008页

作者： William Imamura Erik Oda Usuda Lucas Soares Paixao Nicolau Molina Bom Angelo Marcio Gomes Alexandre Magnus Gomes Carvalho Faculdade de Engenharia Mec(a)nica UNICAMPCEP 13083-860CampinasSPBrazil Universidade Federal de Sāo Paulo UNIFESPCEP 09913-030DiademaSPBrazil Instituto de Física Gleb Wataghin UNICAMPCEP 13083-859CampinasSPBrazil Catalan Institute of Nanoscience and Nanotechnology ICN208860 BelaterraBarcelonaSpain The Institute of Photonic Sciences ICFO08193 CastelldefelsBarcelonaSpain Instituto de Física UFRJCEP 21941-972Rio de JaneiroRJBrazil Departamento de Engenharia Mec(a)nica UEMCEP 87020-900MaringáPRBrazil

Solid-state cooling based on caloric effects is considered a viable alternative to replace the conventional vapor-compression refrigeration *** barocaloric materials,recent results show that elastomers are promising candidates for cooling applications around *** the present paper,we report supergiant barocaloric effects observed in acetoxy silicone rubber—a very popular,low-cost and environmentally friendly *** values of adiabatic temperature change and reversible isothermal entropy change were obtained upon moderate applied pressures and relatively low *** huge barocaloric changes are associated both to the polymer chain rearrangements induced by confined compression and to the first-order structural *** results are comparable to the best barocaloric materials reported so far,opening encouraging prospects for the application of elastomers in near future solid-state cooling devices.

关键词： Solid-state cooling Barocaloric effect Elastomer Silicone rubber Crystalline-amorphous transition

Evidence of endometrial amino acid metabolism and transport modulation by peri-ovulatory endocrine profiles driving uterine receptivity

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Journal of Animal Science and Biotechnology 2017年第4期8卷 852-865页

作者： Moana Rodrigues Franca Maressa Izabel Santos da Silva Guilherme Pugliesi Veerle Van Hoeck Mario Binelli Department of Animal Reproduction School of Veterinary Medicine and Animal ScienceUniversity of Sao Paulo225Duque de Caxias Norte Ave.Jd.Elite13635-900 PirassunungaSPBrazil Gamete Research Centre University of AntwerpAntwerpBelgium

Background: In beef cattle, changes in the periovulatory endocrine milieu are associated with fertility and conceptus growth. A large preovulatory follicle(POF) and the resulting elevated concentrations of progesterone(P4) during diestrus positively affect pregnancy rates. Amino acids(AA) are important components of maternally derived secretions that are crucial for embryonic survival before implantation. The hypothesis is that the size of the POF and the concentration of P4 in early diestrus modulate the endometrial abundance of SLC transcripts related to AA transport and metabolism and subsequently impact luminal concentrations of AA. The follicle growth of Nelore cows was manipulated to produce two experimental groups: large POF and CL(LF-LCL group) and small POF and CL(SF-SCL group). On Day 4(D4; Experiment 1) and Day 7(D7; Experiment 2) after Gn RH-induced ovulation(Gn RH treatment = D0), the animals were slaughtered and uterine tissues and uterine washings were collected. q RT-PCR was used to evaluate the expression levels of AA transporters in D4 and D7 endometrial *** concentrations of AA were quantified in D4 and D7 uterine washings by ***: Transcript results show that, on D4, SLC6 A6, SLC7 A4, SLC17 A5, SLC38 A1, SLC38 A7 and SCLY and on D7 SLC1 A4, SLC6 A1, SLC6 A14, SLC7 A4, SLC7 A7, SLC7 A8, SLC17 A5, SLC38 A1, SLC38 A7, SLC43 A2 and DDO were more abundant in the endometria of cows from the LF-LCL group(P < 0.05). In addition, concentrations of AA in the uterine lumen were influenced by the endocrine profiles of the mother. In this context, D4 uterine washings revealed that greater concentrations of taurine, alanine and α-aminobutyric acid were present in SF-SCL(P < 0.05).In contrast, lower concentrations of valine and cystathionine were quantified on D7 uterine washings from SF-SCL cows(P < 0.05).Conclusion: The present study revealed an association between the abundance of transcripts related to AA transport and metabolism in the endo

关键词： Amino acids Beef cattle Sex steroids Uterus

Multi-planet extrasolar systems-detection and dynamics

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Research in Astronomy and Astrophysics 2012年第8期12卷 1044-1080页

作者： Cristian Beaug Sylvio Ferraz-Mello Tatiana A.Michtchenko Instituto de Astronomía Teóricay Experimental Observatório Astronómico de CórdobaUniversidad de CórdobaArgentina Instituto de Astronomia Geofísica e Cie ncias AtmosfricasUniversidade de So PauloBrasil

20 years after the discovery of the first planets outside our solar system, the current exoplanetary population includes more than 700 confirmed planets around main sequence stars. Approximately 50% belong to multiple-planet systems in very diverse dynamical configurations, from two-planet hierarchical systems to multiple resonances that could only have been attained as the consequence of a smooth large- scale orbital migration. The first part of this paper reviews the main detection tech- niques employed for the detection and orbital characterization of multiple-planet sys- tems, from the （now） classical radial velocity （RV） method to the use of transit time variations （TTV） for the identification of additional planetary bodies orbiting the same star. In the second part we discuss the dynamical evolution of multi-planet systems due to their mutual gravitational interactions. We analyze possible modes of motion for hi- erarchical, secular or resonant configurations, and what stability criteria can be defined in each case. In some cases, the dynamics can be well approximated by simple ana- lytical expressions for the Hamiltonian function, while other configurations can only be studied with semi-analytical or numerical tools. In particular, we show how mean- motion resonances can generate complex structures in the phase space where different libration islands and circulation domains are separated by chaotic layers. In all cases we use real exoplanetary systems as working examples.

关键词： planetary systems -- planetary systems: formation

A Weierstrass Representation Formula for Minimal Surfaces in H_3 and H^2×R

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1603-1612页

作者： Francesco MERCURI StefanoMONTALDO PaolaPIU Departamento de Matematica.C.P.6065 IMECCUNICAMP UniversitàdegliStudi di Cagliari Dipartimento di Matematica

We give a general setting for constructing a Weierstrass representation formula for simply connected minimal surfaces in a Riemannian manifold. Then, we construct examples of minimal surfaces in the three dimensional ... 详细信息

关键词： Minimal immersions Weierstrass representation Heisenberg group Hyperbolic space

Multidimensional Projections for Visual Analysis of Social Networks

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Journal of Computer Science & Technology 2012年第4期27卷 791-810页

作者： Rafael Messias Martins Gabriel Faria Andery Henry Heberle Fernando Vieira Paulovich Alneu de Andrade Lopes Helio Pedrini Rosane Minghim Institute of Mathematics and Computer Science University of Sao PauloSao Carlos 13566-590Brazil CPM Braxis Capgemini Sao Paulo 04543-900Brazil Institute of Computing University of CampinasCampinas-SP 13083-852Brazil

Visual analysis of social networks is usually based on graph drawing algorithms and tools. However, social networks are a special kind of graph in the sense that interpretation of displayed relationships is heavily dependent on context. Context, in its turn, is given by attributes associated with graph elements, such as individual nodes, edges, and groups of edges, as well as by the nature of the connections between individuals. In most systems, attributes of individuals and communities are not taken into consideration during graph layout, except to derive weights for force-based placement strategies. This paper proposes a set of novel tools for displaying and exploring social networks based on attribute and connectivity mappings. These properties are employed to layout nodes on the plane via multidimensional projection techniques. For the attribute mapping, we show that node proximity in the layout corresponds to similarity in atgribute, leading to easiness in locating similar groups of nodes. The projection based on connectivity yields an initial placement that forgoes force-based or graph analysis algorithm, reaching a meaningful layout in one pass. When a force algorithm is then applied to this initial mapping, the final layout presents better properties than conventional force-based approaches. Numerical evaluations show a number of advantages of pre-mapping points via projections. User evaluation demonstrates that these tools promote ease of manipulation as well as fast identification of concepts and associations which cannot be easily expressed by conventional graph visualization alone. In order to allow better space usage for complex networks, a graph mapping on the surface of a sphere is also implemented.

关键词： social network visual exploration multidimensional visualization