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1.
Materials (Basel) ; 14(14)2021 Jul 07.
Article in English | MEDLINE | ID: mdl-34300718

ABSTRACT

The effect of the addition volume of Ni on the microstructures and tensile and fatigue properties of Sn-6.4Sb-3.9Ag (mass%) was investigated using micro-size specimens. The addition of Ni into Sn-6.4Sb-3.9Ag tends to increase the number of grains formed in the solidification process and produce a high-angle grain boundary. An amount of 0.1% proof stress of Sn-6.4Sb-3.9Ag decreases with an increase in the Ni addition volume at a strain rate of 2.0 × 10-1 s-1. The effect of the addition of Ni into Sn-6.4Sb-3.9Ag on tensile strength is negligible at both 25 °C and 175 °C. The elongation of Sn-6.4Sb-3.9Ag decreases with an increase in the Ni addition volume at 25 °C according to the fracture mode change from ductile chisel point fracture to shear fracture. The effect of the addition of Ni into Sn-6.4Sb-3.9Ag on the elongation is negligible at 175 °C. The low cycle fatigue test result shows that the fatigue life does not degrade even at 175 °C in all alloys investigated. The fatigue life of Sn-6.4Sb-3.9Ag-0.4Ni (mass%) is superior to those of Sn-6.4Sb-3.9Ag and Sn-6.4Sb-3.9Ag-0.03Ni (mass%) in the high cycle fatigue area. The electron back scattering diffraction (EBSD) analysis result shows that fine recrystallized grains are generated at the cracked area in Sn-6.4Sb-3.9Ag-0.4Ni in the fatigue test at 175 °C, and the crack progresses in a complex manner at the grain boundaries.

2.
Reprod Med Biol ; 15(3): 187-189, 2016 07.
Article in English | MEDLINE | ID: mdl-29259436

ABSTRACT

Climacteric women are able to become pregnant using oocytes donated earlier in life. However, adverse effects on such donated oocytes have been identified. We report a case of a successful dichorionic diamniotic twin pregnancy achieved using autologous fertilized cryopreserved oocytes in a climacteric woman. A 51-year-old woman became pregnant using autologous fertilized oocytes that had been frozen for 15 years. On her first visit, multiple leiomyoma of the uterus and gestational diabetes mellitus were diagnosed, and proteinuria began to appear at 30 weeks. In spite of our concerns these complications did not exacerbate and the clinical course for both mother and neonates was favorable. This is the first report of a live twin birth achieved using autologous cryopreserved oocytes in a climacteric woman. This case report may be of value to women who desire postponement of their infertility treatment and the professional assisted reproduction community.

3.
J Pharmacol Exp Ther ; 350(2): 403-11, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24917544

ABSTRACT

Previous studies have demonstrated that methylphenidate, MDMA (3,4-methylenedioxymethamphetamine), and other psychostimulants exert stimulant-like subjective effects in humans. Furthermore, MDMA and methylphenidate substitute for the discriminative stimulus effects of psychostimulants, such as amphetamine and cocaine, in animals, which suggests that MDMA and methylphenidate may produce similar discriminative stimulus effects in rats. However, there is no evidence regarding the similarities between the discriminative stimulus effects of MDMA and methylphenidate. To explore this issue, cross-substitution, substitution, and combination tests were conducted in rats that had been trained to discriminate between MDMA (2.5 mg/kg) or methylphenidate (5.0 mg/kg) and saline. In the cross-substitution tests, MDMA and methylphenidate did not cross-substitute for each other. In the substitution test, methamphetamine substituted for the discriminative stimulus effects of methylphenidate, but not for those of MDMA. Furthermore, ephedrine and bupropion, which activate dopaminergic and noradrenergic systems, substituted for the discriminative stimulus effects of methylphenidate. On the other hand, serotonin (5-HT) receptor agonists 5-HT1A and 5-HT2 fully substituted for the discriminative stimulus effects of MDMA. These results suggest that activation of the noradrenergic and dopaminergic systems is important for the discriminative stimulus effects of methylphenidate, whereas activation of the serotonergic system is crucial for the discriminative stimulus effects of MDMA. Even though MDMA, like psychostimulants, exerts stimulant-like effects, our findings clearly indicate that the discriminative stimulus effects of MDMA are distinctly different from those of other psychostimulants in rats.


Subject(s)
Central Nervous System Stimulants/pharmacology , Discrimination Learning/drug effects , Methylphenidate/pharmacology , N-Methyl-3,4-methylenedioxyamphetamine/pharmacology , Animals , Benzazepines/pharmacology , Dose-Response Relationship, Drug , Male , Rats , Rats, Inbred F344 , Receptor, Serotonin, 5-HT1A/physiology , Receptors, Serotonin, 5-HT2/physiology , Receptors, sigma/physiology , Sigma-1 Receptor
4.
Fertil Steril ; 98(2): 471-9.e1, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22633650

ABSTRACT

OBJECTIVE: To study the expression and function of adiponectin and its receptors in mouse and human follicle cells and in early embryo development. DESIGN: Whole ovaries, granulosa cells, and cumulus-oocyte complexes isolated from immature mice before and during hormone-induced ovulation were used to analyze the expression of adiponectin, its receptors, and ovulation-related genes; human cumulus cells and granulosa cells were isolated from patients undergoing in vitro fertilization (IVF) procedures. SETTING: Multicenter. PATIENT(S): Women in IVF programs in Japan and the United States. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Expression of adiponectin receptors and fertility. RESULT(S): Adiponectin expression is absent/low in mouse and human granulosa cells and cumulus cells. Adiponectin receptors are hormonally regulated in mouse granulosa and cumulus cells in vivo and in culture. Adiponectin differentially alters the expression of Adipor1/Adipor2 as well as genes related to steroidogenesis, ovulation, and apoptosis in cumulus cells versus granulosa cells. Adiponectin enhances oocyte maturation and early embryo development in mouse and human IVF procedures. CONCLUSION(S): Adiponectin can modulate not only follicle growth but also embryo development in mice and humans.


Subject(s)
Adiponectin/physiology , Cumulus Cells/metabolism , Embryonic Development/physiology , Fertility/physiology , Granulosa Cells/metabolism , Receptors, Adiponectin/physiology , Adiponectin/metabolism , Animals , Cells, Cultured , Cumulus Cells/physiology , Female , Granulosa Cells/physiology , Humans , Mice , Mice, Inbred C57BL , Oocyte Retrieval/methods
5.
Reprod Biomed Online ; 18(5): 635-43, 2009 May.
Article in English | MEDLINE | ID: mdl-19549441

ABSTRACT

Despite polycystic ovaries (PCO) being a common morphology in women with polycystic ovary syndrome and regular menstruation, the regulatory principles in the morphogenesis of antral follicles have not yet been elucidated. In recognition of the complementary interaction between androgen-induced expression of the FSH receptor and FSH-augmented expression of the androgen receptor in granulose cells of antral follicles, a possible correlation of antral follicle count (AFC) and pituitary-ovarian androgenic function was investigated in 180 infertile women over days 3-5 of the menstrual cycle. Six discrete types of PCO with decreasing pituitary-ovarian androgenic function were identified: Type I (classical Stein-Leventhal syndrome), Type II (hyperandrogenemism), Type III (singular hyper-LH), Type IV (cryptic hyperandrogenism), Type V (relative LH dominancy) and Type VI (relative FSH dominancy), in parallel to a diminishing number of AFC from Type I to Type VI. Because during the early follicular phase of the cycle until the selection of the dominant follicle, antral follicles are composed of newly emerged healthy follicles plus atretic antral follicles that remain non-ovulated from previous cycles, it is proposed that the six types of PCO may represent the folliculogenetic spectra along which PCO morphogenesis proceeds.


Subject(s)
Morphogenesis/physiology , Ovary/growth & development , Polycystic Ovary Syndrome/classification , Polycystic Ovary Syndrome/pathology , Adult , Female , Gonadotropins, Pituitary/blood , Humans , Immunoassay , Infertility, Female/etiology , Ovary/pathology , Polycystic Ovary Syndrome/complications , Statistics, Nonparametric , Testosterone/blood
6.
Am J Reprod Immunol ; 58(4): 383-7, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17845209

ABSTRACT

PROBLEM: Recurrent spontaneous abortion (RSA) is defined by at least three consecutive abortions in otherwise healthy couples. Paternal lymphocyte alloimmunization therapy (PLAT) is an effective therapy for RSA in some cases, but there are no predictive markers about the effectiveness of PLAT. METHOD OF STUDY: Forty-two consecutive cases with primary RSA treated by PLAT and 23 controls were the subjects. Polymorphisms of human leukocyte antigen (HLA)-E, HLA-G, HLA-A, HLA-B, HLA-C and HLA-DRB1 were investigated by sequenced based typing. Promoter polymorphism and a 14 bp ins/del polymorphism in exon 8 were also investigated for HLA-G. RESULTS: Thirty-eight RSA wives became pregnant within 1 year after PLAT. Among them, 27 obtained babies (succeeded PLAT cases), while 11 again aborted with no detectable chromosomal abnormalities in the aborted fetuses (aborted PLAT cases). The frequencies of HLA-G*010401, A*2402, B*5201, and DRB1*1502 were significantly increased in the aborted cases than those in the succeeded cases or controls. Of note, HLA-G*010401 was found in all aborted cases whereas it was found in 51.9% of succeeded cases (odds ratio = 21.4, P = 0.006, P(c) = 0.03), and the presence of HLA-G*010401 could predict the abortion after PLAT with sensitivity and specificity of 100% and 48.1%, respectively. CONCLUSION: Human leukocyte antigen testing may be useful for predicting effectiveness of PLAT in RSA.


Subject(s)
Abortion, Habitual/therapy , HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Lymphocyte Transfusion , Polymorphism, Genetic , Abortion, Habitual/genetics , Abortion, Habitual/immunology , Female , Gene Frequency , Genetic Predisposition to Disease , HLA-A Antigens/genetics , HLA-B Antigens/genetics , HLA-C Antigens/genetics , HLA-DR Antigens/genetics , HLA-DRB1 Chains , HLA-G Antigens , Haplotypes , Humans , Live Birth , Patient Selection , Pregnancy , Treatment Outcome
7.
Reprod Biomed Online ; 14(1): 49-56, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17207331

ABSTRACT

The predictive value of the morphology of the cumulus--oocyte complex (COC) has not yet been explored as a possible factor contributing to the success of human in-vitro maturation (IVM). In the present study, development-supporting competency of oocytes encircled in a large ( > or = 5) (grade A), moderate (3 approximately 4) (grade B) or small ( < or = 2) (grade C) number of cumulus cell layers was assessed, together with changes in hormonal profile following a truncated course of 150 IU pure FSH administration for 3 days prior to aspiration on laparoscopy indicated for endometriosis. FSH priming increased the number of COC aspirated without changing the proportion of the three morphological types of COC, which were then subjected to IVM in the presence of 200 mIU/ml FSH plus 1000 mIU/ml human chorionic gonadotrophin, followed by intracytoplasmic sperm injection. The highest development-supporting competence was observed not with oocytes in grade A COC harvested from natural cycles, but with oocytes in grade B COC from FSH-primed cycles. Hormonal profiles in patients bearing grade B COC were characterized by moderate response in oestradiol and progesterone production following FSH, with LH/FSH ratio being below 1.0. It is concluded that an optimal window of hormonal profile(s) may exist for follicle aspiration to obtain grade B COC in FSH-stimulated human IVM cycles.


Subject(s)
Estrogens/blood , Follicle Stimulating Hormone/blood , Luteinizing Hormone/blood , Oocytes/cytology , Progesterone/blood , Cell Culture Techniques , Female , Follicle Stimulating Hormone/pharmacology , Humans , Oocytes/drug effects , Oocytes/growth & development
8.
Reprod Biomed Online ; 12(5): 622-9, 2006 May.
Article in English | MEDLINE | ID: mdl-16790109

ABSTRACT

Asynchrony between embryo development and endometrial differentiation is the limiting step of successful pregnancy in assisted reproduction. The aim of this study was to investigate whether or not post-thaw synchronization culture of day 5-6 frozen embryos, prior to transfer, with endometrial differentiation resulted in pregnancy. A total of 142 cycles of 134 patients were transferred in three protocols. Blastocysts with cavities larger than half of the entire blastocyst volume were transferred without synchronizing culture on day 5 or 6 of progesterone commencement (P5/6) in hormone replacement treatment cycles (protocol 1). Blastocysts with cavitation below half of the entire blastocyst were cultured for 1 or 2 days after thawing prior to transfer on P5 or P6 (protocol 2). Morulae and very early stage blastocysts were thawed on the days corresponding to P5 and P6, and only the embryos that reached expanded or hatching blastocysts were transferred on P7 without synchronizing culture (protocol 3). Pregnancy rate in protocol 2 (32.0%) was comparable with that of protocol 1 (35.0%). It is concluded that developmentally retarded frozen embryos can be rescued with synchronizing culture prior to transfer by evading asynchrony.


Subject(s)
Blastocyst/physiology , Embryo Culture Techniques , Embryo Transfer , Embryonic Development , Adult , Blastocyst/drug effects , Blastocyst/pathology , Cryopreservation , Embryo Implantation , Female , Humans , Pregnancy , Pregnancy Rate , Progesterone/pharmacology , Tissue Preservation/methods
9.
Biochim Biophys Acta ; 1763(3): 290-5, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16569452

ABSTRACT

Mild hypothermia shows protective effects on patients with brain damage and cardiac arrest. To elucidate the molecular mechanisms underlying these effects, we analyzed the effects of low culture temperature (32 degrees C) and cold-inducible RNA-binding protein (Cirp) expression on apoptosis in vitro. In BALB/3T3 cells treated with tumor necrosis factor (TNF)-alpha and cycloheximide, the down-shift in temperature from 37 degrees C to 32 degrees C increased the expression of Cirp and suppressed the apoptosis. Activation of caspase-8 was suppressed, and the level of phosphorylated extracellular signal-regulated kinase (ERK) was increased. Transduction of Cirp into the Cirp-deficient mouse fibroblasts increased the level of phosphorylated ERK and suppressed the TNF-alpha-induced apoptosis both at 37 degrees C and 32 degrees C. The ERK-specific inhibitor PD98059 decreased the cytoprotective effect of Cirp as well as that of low culture temperature. These data suggest that mild hypothermia protects cells from TNF-alpha-induced apoptosis, at least partly, via induction of Cirp, and that Cirp protects cells by activating the ERK pathway.


Subject(s)
Apoptosis/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , RNA-Binding Proteins/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Animals , Cell Survival , Cells, Cultured , Cold Temperature , Enzyme Activation/drug effects , Fibroblasts/cytology , Humans , Mice , Mice, Inbred BALB C , Mice, Knockout
10.
Mol Hum Reprod ; 11(7): 471-6, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16123073

ABSTRACT

Decidualization of the endometrial stromal cells (ESC), considered to be stimulated by progesterone and/or cAMP, is crucial for embryo implantation and placentation. In this study, we isolated a novel clone encoding decidual protein induced by progesterone (Depp) from a human ESC cDNA library enriched with progesterone-inducible genes. Depp mRNA was expressed in various human tissues including placenta, ovary and kidney. Increased expression of Depp was observed in endometria during mid- and late-secretory phases and 1st trimester deciduas. In vitro, Depp mRNA was induced in ESC within 30 min of progesterone treatment, which was inhibited by the antiprogestin RU486. Androgen alone also induced Depp expression. Depp increased the level of phosphorylated Erk and activated the Elk-1 transcription factor in human embryonal kidney 293 cells, suggesting that Depp modulates the effects of progesterone during decidualization and in the decidua by affecting gene expression. Elucidation of the biological function of Depp in the endometrium will facilitate our understanding of the molecular mechanisms of decidualization and placental development.


Subject(s)
Endometrium/metabolism , Progesterone/physiology , Proteins/genetics , ets-Domain Protein Elk-1/metabolism , Amino Acid Sequence , Cell Line , Cells, Cultured , DNA, Complementary , Decidua/cytology , Decidua/metabolism , Endometrium/cytology , Female , Gene Expression Regulation/physiology , Gene Library , Humans , Intracellular Signaling Peptides and Proteins , Proteins/physiology , RNA, Messenger/metabolism , Signal Transduction/physiology , Stromal Cells/metabolism , ets-Domain Protein Elk-1/genetics
11.
J Assist Reprod Genet ; 19(9): 420-5, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12408536

ABSTRACT

Gender selection is a matter of great concern to a cohort of parents. To what extent the methods available are ethically acceptable at present differs depending upon the society and times the couples live in. In the present communication, the current situation in Japan in use for gender selection by empirical methods without sperm separation, conventional methods with sperm separation and preimplantation genetic diagnosis of human embryos has been provided and considered in the light of human dignity as well as human right.


Subject(s)
Sex Preselection/ethics , Economics , Family Characteristics , Humans , Japan/ethnology , Preimplantation Diagnosis/ethics , Preimplantation Diagnosis/methods , Sex Preselection/methods , Women's Rights
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