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1.
Nanomaterials (Basel) ; 12(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35564171

RESUMO

Pd nanoparticles were immobilized on an acrylonitrile-butadiene-styrene copolymer (ABS) substrate using ionizing radiation. The samples were prepared by irradiating plastic zipper packs containing ABS substrates and a Pd(NO3)2 aqueous solution with a high-energy electron beam (4.8 MeV). Pd nanoparticles immobilized on the ABS substrate surfaces were observed using scanning electron microscopy (SEM). The chemical state of Pd was found to be coordinated to a carbonyl group or a metallic state by X-ray photoelectron spectroscopy (XPS) measurements. The peel strength of the Cu film on the Pd/ABS samples was 0.7 N/mm or higher. This result shows that the prepared Pd/ABS samples have high adhesion strength, despite not undergoing treatments such as etching with chromic acid. This method is expected to immobilize metal nanoparticles, not only on plastic plates but also on various other materials.

2.
J Neuroendovasc Ther ; 14(9): 339-344, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-37501671

RESUMO

Objective: To describe our 1-year experience of the practical use of a mobile communication application by our stroke team. Methods: The mobile Join application (Allm Inc., Tokyo, Japan) was introduced into our stroke team for the purpose of immediate sharing of the patient information. We analyzed the usage situation for 1 year after the introduction of Join, particularly its efficacy in improving the door-to-puncture time (D2P) for thrombectomy cases, and reported our inter-hospital collaboration with the use of Join. Results: The total number of events notified by Join was 337, and they included acute stroke potentially leading to reperfusion therapy in 23% (76 events), head trauma in 14%, brain hemorrhage in 12%, other infarction in 10%, subarachnoid hemorrhage in 8%, and the others in 34%. The information of the patients was shared among the team members before arrival to our hospital in 42% of acute stroke cases. Of 31 patients undergoing mechanical thrombectomy, the median interval between arrival and groin puncture for the directly transported patients with/without pre-hospital information was 77.5 min/87 min, respectively, whereas that of the patients transferred from primary hospitals with/without pre-hospital information was 19 min/71 min (p <0.0001), respectively, demonstrating the efficacy of information sharing in advance through Join in improving the timing of endovascular therapy. For inter-hospital collaboration using the telestroke system, we concluded the partnership agreement with three local primary hospitals by communication via Join at a reasonable cost. Conclusion: Active and effective utilization of the mobile Join application for communication by our stroke team was demonstrated, and it is expected to promote inter-hospital collaboration in stroke treatment.

3.
Molecules ; 23(7)2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29997380

RESUMO

The In-mediated allylation of carbonyl compounds can be performed in various types of solvents including ionic liquids. However, we have found that in [bmim][BF4] (where bmim = 1-butyl-3-methylimidazolium), the In-mediated coupling of crotyl bromide with benzaldehyde gives a complex mixture, and some additives, such as halides and amines, are crucial for the successful conversion to the corresponding γ-adduct. Instead, the addition of alcohols or water promotes the formation of the α-adduct. An asymmetric induction with up to 62% enantiomeric excess (ee) was observed employing cinchonidine as an additive in a binary solvent consisting of an ionic liquid and dichloromethane.


Assuntos
Índio/química , Líquidos Iônicos/química , Paládio/química , Sais/química , Benzaldeídos/química , Catálise , Imidazóis/química , Cloreto de Lítio/química
4.
Reprod Med Biol ; 16(2): 133-138, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-29259460

RESUMO

Aim: To examine the potential of bovine follicular fluid (BFF) to attract bull spermatozoa. Methods: The ability of the BFF to attract bull sperm was evaluated by observing changes in sperm migration after being placed in a cross-column chamber. The movement parameters of the heads and flagella of the sperm that were attracted to the BFF were analyzed by using the Computer Assisted Sperm Analysis system. Results: It was observed that 61.6% of the bull sperm migrated toward the BFF when the BFF was used at a concentration of 0.1%, but 67.2% of the sperm did not migrate toward the BFF at a concentration of 10%. Relatively larger numbers of both precapacitated and postcapacitated bull sperm migrated toward the BFF (0.1%). The ability of the 0.1% BFF to attract sperm probably affected both the normal artificial insemination (AI) fertility sperm and the poor AI fertility spermatozoa. The flagellar curvilinear ratio of the sperm winding to the 0.1% BFF was significantly higher than that of the prewinding sperm. Conclusion: These results could suggest that BFF potentially attracts bull sperm at a certain concentration, irrespective of the capacitation status of the sperm. Although the mechanism by which this attraction occurs remains unclear, these data imply that it could be related to BFF-dependent changes in the sperm flagellar curvilinear ratio.

5.
J Reprod Dev ; 63(2): 143-148, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28049872

RESUMO

Thermotaxis that sperm migrate to higher temperature area has been confirmed in rabbit and human. In this study, we examined the migration ability of bull sperm in a temperature gradient to confirm thermotaxis and elucidate the involvement of calcium in such thermotaxis, as well as the relation between sperm capacitation and bull fertility. Thermotaxis was evaluated in a temperature gradient of 34-42ºC using a cross-type column 22-mm long, 40-mm wide, and 100-µm deep. Significantly more sperm migrated to the high-temperature area of 39ºC in a 2ºC temperature gradient, and to 40ºC in a 1ºC temperature gradient. In calcium-free, BAPTA containing medium, and EGTA containing medium, the migrated sperm ratio in the two temperature areas was almost the same. In media containing lanthanum, ruthenium red, and 2APB, we could not confirm thermotaxis. Pre- and post-capacitated sperm migrated to the high-temperature area, expressing thermotaxis. The sperm from high-fertility bulls showed clear thermotaxis. Based on these results, thermotaxis of bull sperm was confirmed and the involvement of both calcium channels and intracellular stored calcium in thermotaxis was suggested. Although the sample size of bulls was quite small, the difference in thermotaxis may have been associated with bull fertility. Sperm thermotaxis evaluation has potential as a predictor of bull fertility.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Espermatozoides/metabolismo , Resposta Táctica/fisiologia , Animais , Bovinos , Masculino , Capacitação Espermática/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/citologia , Temperatura
6.
J Reprod Dev ; 62(4): 415-22, 2016 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-27180924

RESUMO

Transient Receptor Potential Vanilloid (TRPV) 4 is one of the temperature-sensitive ion channels involved in temperature receptors, and it is known to be activated from 35 to 40ºC. Here we analyzed sperm motility function of Trpv4 knockout (KO) mouse in temperature-gradient conditions to elucidate the thermotaxis of mouse sperm and the involvement of TRPV4 in thermotaxis. The sperm were introduced at the vertical column end of a T-shaped chamber filled with medium in a plastic dish, and we measured the number of sperm that arrived at both ends of the wide column where we had established a temperature gradient of approx. 2ºC, and we evaluated the sperm's thermotaxis. Large numbers of wild-type (WT) mouse sperm migrated into the high level of the temperature gradient that was set in the wide column, and thermotaxis was confirmed. The ratio of migrated sperm at the high temperature level of the T-shaped chamber was decreased in the KO sperm and Ruthenium red (a TRPV antagonist) treated sperm compared with the WT sperm. The thermotaxis of the mouse sperm was confirmed, and the involvement of TRPV4 in this thermotaxis was suggested.


Assuntos
Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Canais de Cátion TRPV/metabolismo , Resposta Táctica/fisiologia , Animais , Masculino , Camundongos , Camundongos Knockout , Canais de Cátion TRPV/genética
7.
Sci Rep ; 6: 20436, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26853703

RESUMO

We show a simple and effective way to improve the vortex irreversibility line up to very high magnetic fields (60T) by increasing the density of second phase BaZrO3 nanoparticles. (Y0.77,Gd0.23)Ba2Cu3Oy films were grown on metal substrates with different concentration of BaZrO3 nanoparticles by the metal organic deposition method. We find that upon increase of the BaZrO3 concentration, the nanoparticle size remains constant but the twin-boundary density increases. Up to the highest nanoparticle concentration (n ~ 1.3 × 10(22)/m(3)), the irreversibility field (Hirr) continues to increase with no sign of saturation up to 60 T, although the vortices vastly outnumber pinning centers. We find extremely high Hirr, namely Hirr = 30 T (H||45°) and 24 T (H||c) at 65 K and 58 T (H||45°) and 45 T (H||c) at 50K. The difference in pinning landscape shifts the vortex solid-liquid transition upwards, increasing the vortex region useful for power applications, while keeping the upper critical field, critical temperature and electronic mass anisotropy unchanged.

8.
Reprod Med Biol ; 9(2): 73-81, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29699332

RESUMO

PURPOSE: Selenium (Se) and vitamin E (Vit-E), as an integral part of antioxidant systems, play an important role in the motility and acrosome reaction (AR) of mammalian spermatozoa. The purpose of this study was to investigate the effect of Se and Vit-E on motility, viability, AR and accumulation of ammonia in the culture medium during different incubation periods in porcine sperm. METHODS: Sperm samples were washed, swum-up and incubated at 37°C for 1 and 3 h in Sp-TALP medium supplemented with sodium selenite (SS), seleon l-methionine (SeMet) and Vit-E in the presence or absence of ammonia. Sperm motility was determined on the basis of movement quality examined by phase microscopy. Viability and AR of spermatozoa were assessed by Hoechst 33258 and chlortetracycline (CTC) staining technique, and accumulation of ammonia was measured by the indophenol method. The incorporation of 14C(U)-glucose was assessed with a liquid scintillation counter. RESULTS: In experiment 1, the sperm motility, viability, AR and incorporation of 14C(U)-glucose increased significantly (P < 0.05) in SS, SeMet and Vit-E (5, 5 µg/l and 1.0 mM, respectively) compared with the control. In experiment 2, treatment of the sperm with SeMet and SeMet + Vit-E in the presence of 300 µM ammonia also resulted in a significant increase (P < 0.05) in the rate of motility, viability, AR and incorporation of 14C(U)-glucose. In contrast, the accumulation of ammonia was reduced by SeMet and SeMet + Vit-E compared with the other treatments. CONCLUSIONS: These findings indicate that SeMet and SeMet + Vit-E may play an important role in reducing the accumulation of ammonia and subsequently in increasing the rate of AR and the utilization of glucose in porcine spermatozoa.

9.
J Reprod Dev ; 56(2): 279-84, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20035109

RESUMO

The efficiency of a porcine embryo vitrification method that uses water-soluble films of pullulan, a naturally-occurring polysaccharide polymer, was compared with two other types of vitrification methods using different devices and solutions for vitrification and warming. Blastocysts collected in vivo and vitrified by the conventional straw (ST), Cryotop((R)) (MVC) or pullulan film vitrification (PFV) methods were stored in liquid nitrogen for a certain period of time, after which the cryoprotective agents were removed by stepwise dilution. Fresh embryos were used as controls for the non-vitrification group. The vitrified-warmed embryos were incubated in TCM199 with 0.1 mM beta-mercaptoethanol and 20% fetal bovine serum for 24 h at 38.5 C in humidified air with 5% CO(2) to evaluate their viability. The survival rate of embryos in the ST group (48.3%) was significantly lower than that of those in the MVC (70.7%), PFV (79.0%) and non-vitrification (94.4%) groups. The oxygen consumption rate after vitrification was significantly lower than that before vitrification in the ST group, but was not significantly different in the MVC and PFV groups. Both the oxygen consumption rates of embryos after warming and the live cell numbers in the ST group were lower than those in the MVC group, while they did not differ significantly between the PFV and MVC groups. There was a correlation between the oxygen consumption rate and the number of live cells in vitrified embryos after warming. Our results demonstrated that in vivo-derived porcine embryos could be vitrified using pullulan films.


Assuntos
Criopreservação/métodos , Criopreservação/veterinária , Desenvolvimento Embrionário/fisiologia , Glucanos , Suínos/embriologia , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Técnicas de Cultura Embrionária/veterinária , Feminino , Consumo de Oxigênio/fisiologia , Gravidez , Solubilidade , Temperatura , Água
10.
Reprod Fertil Dev ; 21(5): 696-708, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19486607

RESUMO

Gonocytes are progenitor-type germ cells that arise from primordial germ cells and differentiate further into spermatogonia, thereby initiating spermatogenesis. In the present study, freshly isolated gonocytes were found to have either weak or no expression of pluripotency determining transcription factors, such as POU5F1, SOX2 and C-MYC. Interestingly, the expression of these transcription factors, as well as other vital transcription factors, such as NANOG, KLF4 and DAZL, were markedly upregulated in cultured cells. Cells in primary cultures expressed specific germ cell and pluripotency markers, such as lectin Dolichos biflorus agglutinin (DBA), KIT, ZBTB16, stage-specific embryonic antigen (SSEA-1), NANOG and POU5F1. Using a monoclonal antibody to specifically identify porcine germ cells, the stem cell potential of fresh and cultured cells was determined with a testis xenotransplantation assay. Colonised porcine germ cells were detected only in mouse testes that were either transplanted with fresh testicular cells or with cells from primary cultures. Interestingly, testes transplanted with cells from primary cultures showed colonisation of germ cells in the interstitial space, reflecting their tumourigenic nature. The formation of teratomas with tissues originating from the three germinal layers following the subcutaneous injection of cells into nude mice from primary cultures confirmed their multipotency. The results of the present study may provide useful information for the establishment of multipotent germ stem cell lines from neonatal pig testis.


Assuntos
Animais Recém-Nascidos/metabolismo , Células-Tronco Multipotentes/metabolismo , Espermatozoides/metabolismo , Fatores de Transcrição/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Fator 4 Semelhante a Kruppel , Masculino , Camundongos , Camundongos Nus , Células-Tronco Multipotentes/citologia , Espermatogênese/fisiologia , Espermatozoides/citologia , Transplante de Células-Tronco/efeitos adversos , Suínos , Teratoma/etiologia , Neoplasias Testiculares/etiologia , Testículo/citologia , Testículo/transplante , Fatores de Transcrição/imunologia , Transplante Heterólogo
11.
Reprod Med Biol ; 7(1): 29-36, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29699285

RESUMO

Aim: Relaxin and insulin-like growth factor (IGF)-I have pronounced effects on the male and female reproductive tracts. The aim of this study was to investigate the effects of relaxin and IGF-I on the motility, capacitation, acrosome reaction, cholesterol efflux and utilization of glucose in porcine spermatozoa. Methods: Swim-up separated spermatozoa that had been washed twice were incubated at 37°C for 1 or 4 h in modified Tyrode's albumin lactate pyruvate (mTALP) medium supplemented without (control) or with relaxin (20 ng/mL) or IGF-I (20 ng/mL) or both (10 + 10 ng/mL). Results: Progressive motility and the induction rate of capacitation and acrosome reaction were increased (P < 0.05) by relaxin and IGF-I alone or in combination, especially after 4 h of incubation. Relaxin alone or combined with IGF-I enhanced (P < 0.05) the cholesterol efflux after 4 h, whereas IGF-I alone did not show any significant effect on the cholesterol efflux compared with the control at any time point. The utilization rates of labeled and unlabeled glucose increased (P < 0.05) in spermatozoa incubated with relaxin or IGF-I alone or in combination compared with the control. Conclusion: Thus, supplementation of relaxin alone or combined with IGF-I into the medium possibly plays a beneficial role in porcine spermatozoal prefertilization events in vitro. (Reprod Med Biol 2008; 7: 29-36).

12.
Mol Cell Biochem ; 276(1-2): 133-41, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16132694

RESUMO

Until now, the various proteins highly expressed in adipose tissues have been identified and characterized by traditional gene cloning techniques. However, methods of computer analysis have been developed to compare the levels of expression among various tissues, and genes whose expression levels differ significantly between tissues have been found. Among these genes, we report on the possible function of a new adipose-specific gene, showed higher expression in adipose tissue through 'Search Expression' on Genome Institute of Norvartis Research Foundation (GNF) SymAtlas v0.8.0. This database has generated and analyzed gene expression of each gene in diverse samples of normal tissues, organs, and cell lines. This newly discovered gene product was named adipogenin because of its role in stimulating adipocyte differentiation and development. Adipogenin mRNA was highly expressed in four different fat depots, and exclusively expressed in adipocytes isolated from adipose tissues. The level of adipogenin mRNA was up-regulated in the subcutaneous and visceral adipose tissues of mice fed a high-fat diet compared to those on the control diet. The expression of adipogenin mRNA is dramatically elevated during adipocyte differentiation of 3T3-L1 cells. Troglitazone, which up-regulated peroxisome proliferators-activated receptor gamma2 (PPAR-gamma2) expression, increased adipogenin mRNA expression, although this gene was down-regulated by retinoic acid. Confocal image analyses of green-fluorescent protein-adipogenin (pEGFP-adipogenin) transiently expressed in 3T3-L1 adipocytes showed that adipogenin was strictly localized to membranes and was absent from the cytosol. Moreover, small interfering RNA (siRNA) mediated a reduction of adipogenin mRNA in 3T3-L1 cells and blocked the process of adipocyte differentiation. These results indicate that adipogenin, an adipocyte-specific membrane protein, may be involved with adipogenesis, as one of the regulators of adipose tissue development.


Assuntos
Adipócitos/metabolismo , Adipogenia , Citoplasma/química , Proteínas de Membrana/metabolismo , Regulação para Cima , Células 3T3-L1 , Adipócitos/química , Adipócitos/citologia , Tecido Adiposo/metabolismo , Animais , Diferenciação Celular , Bases de Dados Genéticas , Dieta Aterogênica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
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