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T Aono

Publications and source records attributed to T Aono.

At least 37 records · Page 2Linked to original sources
PubMed2001

Transient increase in the levels of T-helper 1 cytokines in postmenopausal women and the effects of hormone replacement therapy.

The aim of this study was to determine, at least in part, T-cell function in postmenopausal women and the effects of hormone replacement therapy (HRT). Levels of T-helper 1 (Th1) cytokines (IL-2 and IFN-gamma) and T-helper 2 (Th2) cytokines (IL-4 and IL-10) produced by phytohemagglutinin-stimulated whole blood cells from 72 untreated and 44 HRT-treated women were measured by ELISA. Thirteen of the 44 HRT-treated women were examined before and during HRT. The production of IL-2 increased gradually with advance of the postmenopausal period. The levels of IL-2 in women in the early (< or =10 years) and mid (>10 and <30 years) postmenopausal stages were significantly higher than those in women in their second, third and fourth decades. The level in women in the late (> or =30 years) postmenopausal stage, however, was significantly lower than those in women in the early and mid postmenopausal stages. The level of IFN-gamma was highest in women in the mid postmenopausal stage. On the other hand, the levels of Th2 cytokines did not change with age or after menopause until the mid postmenopausal period but were significantly lower in women in the late postmenopausal stage. IFN-gamma levels in women on HRT were significantly lower than those in untreated postmenopausal women at all postmenopausal stages. HRT induced a significant decrease in the production of IL-2 and IL-4. In conclusion, production of Th1 cytokines is augmented in women after menopause. HRT prevents this increase, thereby improving the aberration of Th1/Th2 balance that is implicated in an inadequate immune response and pathological conditions.

Adolescent↗
PubMed2001

Expression of ovarian prolactin receptor in relation to hormonal changes during induction of ovulation in the rat.

We examined the relationships between the expression of the short and long forms of the prolactin (PRL) receptor (PRLR) mRNA in the ovary and changes in the levels of serum hormones such as sex steroid hormones and PRL during induction of ovulation in the rat. The expression of both forms of PRLR mRNA in the ovary was examined by Northern blot analysis in immature female rats treated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Ovarian tissues and blood samples were obtained before treatment, 24 and 48 h after PMSG injection and 4, 6, 8, 12, 24 and 48 h after hCG treatment. Serum levels of 17beta-estradiol, progesterone and PRL were determined by radioimmunoassay. Serum levels of 17beta-estradiol rapidly increased to a maximal level 48 h after PMSG injection and then rapidly declined until 4 h after hCG injection. Serum levels of progesterone gradually increased after PMSG treatment, markedly increased to 114.2 nmol/l 8 h after hCG treatment and remained high until 48 h after hCG treatment. The serum level of PRL peaked at 66.2 microg/l (p < 0.01) 48 h after PMSG injection, and a temporary decrease after hCG treatment was followed by a continuously high level from 8 to 48 h. The expression of the long form of PRLR mRNA increased significantly (p < 0.01) to 688% of the control level after PMSG treatment, while that of the short form increased to only 184% of the control level. The expression of the long form of PRLR-mRNA rapidly declined until 6 h and then gradually increased until 48 h after hCG treatment. On the other hand, the expression of the short form of PRLR mRNA decreased to a nadir 12 h after hCG injection and then increased significantly (p < 0.01) to 142% of the control level. Our results showed that the changes in the short and long forms of PRLR mRNA differed in a time-specific manner and that these two forms are involved in different functions in the rat ovary during induction of ovulation. It is thought that the long form of PRLR mRNA is involved in folliculogenesis, while the short form of PRLR mRNA may play an important role in the formation and maintenance of the corpus luteum in the rat ovulatory cycle.

Animals↗
PubMed2001

Efficacy of every-other-day administration of conjugated equine estrogen and medroxyprogesterone acetate on gonadotropin-releasing hormone agonists treatment in women with endometriosis.

We performed a randomized controlled study to determine the efficacy of add-backed therapy by every-other-day administration of 0.625 mg conjugated equine estrogen (CEE) and 2.5 mg medroxyprogesterone acetate (MPA) on GnRH agonists (GnRH-a) treatment in Japanese women with symptomatic endometriosis. At the end of treatment, serum estrone and estradiol levels in the add-back group (n = 11) were significantly higher than those in the control group (n = 10). The assessment of Beecham classification by bimanual examination, serum CA-125 levels, and the frequency of genital bleeding revealed no significant differences between the two groups. The add-back group showed reduced Kupperman indices relative to those of the control group, and could prevent the loss of bone density. These findings led to a conclusion that GnRH-a therapy added back by every-other-day administration of 0.625 mg CEE and 2.5 mg MPA was a safe and effective treatment for Japanese women with endometriosis.

Adult↗
PubMed2001

Effects of leptin on secretion of LH and FSH from primary cultured female rat pituitary cells.

BACKGROUND: Leptin, which is the product of the obese gene, is believed to play important roles in pubertal development and reproductive function in females. In a study using adult male rats, it was found that leptin stimulated secretion of gonadotropin from the pituitary in a dose-related manner. However, there has been no such study in female rats. OBJECTIVE: To investigate the effects of leptin on the production of LH and FSH from the pituitary in female rats, using primary cultured pituitary cells. METHODS: In this study, we determined body weight, serum leptin concentration and serum estradiol (E(2)) concentration in female Wistar rats at 3, 5, 6, 7, 9 and 11 weeks of age, and cultured pituitary cells from 6-week-old female Wistar rats with leptin (0--10(-7) mol/l) and GnRH (0 or 10(-8) mol/l). Then basal and GnRH-stimulated extra- and intracellular LH and FSH were assayed by RIA. RESULTS: Serum leptin concentration increased with increases in body weight and E(2) concentration. The pubertal serum leptin concentration was about 10(-10) mol/l. At a lower or moderate concentration, leptin produced dose-related increases in both basal and GnRH-stimulated extra- and intracellular LH and FSH in pituitary cells. At a concentration of 10 mol/l, leptin significantly (P<0.05) stimulated both basal and GnRH-stimulated extra- and intracellular LH and FSH. However, at greater concentrations, these effects diminished. CONCLUSIONS: These results indicated that leptin induced pituitary cells to produce and secrete both LH and FSH, with or without GnRH. The concentration of leptin that induced the greatest production of gonadotropins by pituitary cells was 10(-10) mol/l, which was the same as the physiological pubertal concentration. Leptin may be involved in the onset of puberty. It is also conceivable that leptin may be a cause of ovulatory failure, not only in weight loss but also in weight gain.

Animals↗
PubMed2001

Penetrating capacity of human spermatozoa cool preserved in electrolyte-free solution.

OBJECTIVE: To evaluate whether human spermatozoa preserved in electrolyte-free (EF) solution at 4 degrees C possess normal penetrating capacity. STUDY DESIGN: The acrosomal status of human spermatozoa cool preserved in EF solution was evaluated before preservation and before and after reinitiation by using chlortetracycline staining. The zona-free hamster egg sperm penetration test was performed using spermatozoa cool preserved in EF solution. RESULTS: The percentages of capacitated and acrosome-reacted spermatozoa cool preserved in EF solution before reinitiation were similar to those of fresh spermatozoa, but they significantly increased after reinitiation. The penetration rate and fertility index of spermatozoa cool preserved in EF solution were comparable to those of fresh spermatozoa (48.3% vs. 50.8% and 1.37 +/- 0.15 vs. 1.29 +/- 0.10, respectively). CONCLUSION: Human spermatozoa cool preserved in EF solution for one week can possess as much penetrating capacity as fresh spermatozoa.

Acrosome↗
PubMed2000

Hormonal control of mRNA expression of immunoglobulin binding factor in uterine cervix.

Uterine cervical mucus contains an immunoglobulin binding factor (IgBF). It may play a role in preventing antibody production against sperm in the female reproductive tract. To elucidate the mechanism involved in the production of activated IgBF, we determined the effects of hormones on the expression of mRNAs of IgBF and of protein disulfide isomerase (PDI), activating enzyme, in uterine cervix by quantitative RT-PCR. The uterine cervices of female rats were excised at preovulatory, ovulatory, and postovulatory phases. The human uterine cervical adenocarcinoma cells (TCO-2) were cultured for 24 h in serum-free medium containing 17beta-estradiol or progesterone. Expression of IgBF and PDI mRNAs was significantly highest during the ovulatory phase. 17beta-estradiol stimulated the expression of both mRNAs in TCO-2; whereas progesterone was ineffective. In conclusion, estrogen regulates the production of IgBF by the endocervix and PDI in vivo, thereby increasing the level of activated IgBF in the female reproductive tract during the ovulatory phase, allowing sperm to enter the uterine cavity.

Animals↗
PubMed2000

Effect of a novel vasoconstrictor endothelin-1 (1-31) on human umbilical artery.

To clarify the action of a novel endothelin-1 with 31 amino acids, ET-1 (1-31), on fetal circulation, its vasoconstrictive activity on human umbilical and uterine arteries was investigated in comparison with that of a conventional ET-1 (1-21). UFER micro-easy magnus was used for determination of vasoconstriction. The contraction of umbilical artery by KCl was significantly weaker than that of the uterine artery. In ETs, constriction by KCl was set as control, and the rate of constriction of uterine and umbilical arteries was used for comparison. The constriction of human uterine artery induced by ET-1 (1-31) was also significantly weaker than that by ET-1 (1-21). On the contrary, ET-1 (1-31) was a potent constrictor on the umbilical artery equally to ET-1 (1-21). The present study is the first to demonstrate that ET-1 (1-31) has a contractile activity on human vessels. Furthermore, the regulatory mechanism on constriction of umbilical artery is different from that observed in a systemic vessel, indicating a particularly important role of ET-1 (1-31) in fetal circulation.

Adult↗
PubMed2000

Insertion/deletion polymorphism in the angiotensin-converting enzyme gene affects heart weight.

BACKGROUND: Angiotensin (Ang) II, a major regulatory factor for left ventricular mass, is generated from Ang I by ACE. ACE levels are associated with an insertion/deletion (I/D) polymorphism in the ACE gene. The ACE polymorphism should result in varied Ang II concentrations and hence affect left ventricular mass. We therefore investigated whether ACE genotype is a predictor of heart weight. METHODS AND RESULTS: From 693 consecutive patients autopsied between 1994 and 1998 in our hospital, patients with valvular disease, myocardial infarction, or cardiomyopathy were excluded. The remaining 443 autopsy patients were the subjects of our study. The heart weight at autopsy was corrected for body surface area. Genomic DNA was purified from the kidney, and ACE genotype was determined by polymerase chain reaction. Heart weight in the DD genotype (249. 9+/-49.9 g/m(2)) was significantly higher than that in the ID (230. 0+/-51.2 g/m(2); P<0.05) and II (226.8+/-49.8 g/m(2); P<0.01) genotypes. Heart weight was also positively related to age (r=0.145, P<0.0001) and coronary stenosis index (r=0.147, P=0.0019). Multiple regression analysis showed that a history of hypertension (P<0.0001), age (P=0.0001), and DD genotype (P=0.0154) were independent predictors of heart weight. CONCLUSIONS: ACE genotype predicts cardiac mass; however, it was less effective than epigenetic factors such as hypertension or age.

Aged↗
PubMed2000

Microsatellite instability is a late event in the carcinogenesis of uterine cervical cancer.

OBJECTIVE: The purpose of this study was to elucidate the role of genetic instability and LOH in the progression of cervical cancer and also to analyze for correlations between these genetic abnormalities and the clinicopathological characteristics of cervical cancers. METHODS: Seventy-two DNA samples were obtained from 29 carcinoma in situ, 8 microinvasive carcinoma, and 35 invasive cancers. Seven highly polymorphic microsatellite markers representing the chromosome 3p, 6p, and 6q arms were examined by PCR amplification. RESULTS: Microsatellite instability was detected in 8 of 35 (22.9%) invasive cancers and in 1 of 37 (2.7%) early stage cancers (microinvasive cancer and carcinoma in situ). The incidence of MI was statistically higher in invasive cancers (P < 0.02). On the other hand, loss of heterozygosity (LOH) of chromosome 3p was identified in 6/41 (14.6%) invasive cancers and in 3/27 (11.1%) carcinomas in situ. There was no statistical difference between the two groups. There were no significant correlations between the presence of MI or 3p LOH and clinicopathological characteristics including the histological type, FIGO stage, depth of myometrial invasion, lymphovascular involvement, lymph node metastasis, and recurrence. CONCLUSION: Our results indicate that genomic instability is a late event during the carcinogenesis of cervical cancer and is associated with the conversion of cervical intraepithelial neoplasia to an invasive phenotype. To the contrary, LOH of chromosome 3p plays an early role in the development of cervical intraepithelial neoplasia. No significant correlation was observed between the presence of MI or LOH and clinicopathological characteristics.

Adult↗
PubMed2000

Effect of hormone replacement therapy on post-menopausal changes of lymphocytes and T cell subsets.

Immunosenescence is associated with the occurrence of lethal diseases, such as infection and malignancy. Since endocrinosenescence occurs simultaneously with immunosenescence, we determined whether or not lymphocytes and T cell subsets were altered in post-menopausal women. The ability of hormone replacement therapy (HRT) to reverse or modify the aberrations of the cell populations observed in elderly women was also examined. Thirty-nine untreated post-menopausal women and 39 women on HRT were studied. The proportions of lymphocytes and T cell subsets (helper, cytotoxic and immature T cells, and naive and memory/activated T cells) were determined by two color flow cytometry. Thirteen women were examined before and during HRT. At late post-menopause (> or = 30 years post-menopausal period), the proportion of peripheral blood lymphocytes showed a tendency to decline (p=0.06) compared with that at early (< or = 10 years) post-menopause. Significant (p<0.05) decrease in naive T cells and an increase in memory/activated T cells occurred at late post-menopause compared to those at early post-menopause. The percentage of lymphocytes in women on HRT was significantly (p<0.05) higher than that in untreated women at late post-menopausal stage. Furthermore, in a prospective study, HRT induced a significant (p<0.02) increase in the percentage of lymphocytes but showed no effect on the aberrations of naive and memory/activated T cells. HRT prevents the decline in the lymphocytes observed in post-menopausal women. However, HRT appears not to influence the observed alteration in T cell subsets.

Aged↗
PubMed2000

Effective activation method with A23187 and puromycin to produce haploid parthenogenones from freshly ovulated mouse oocytes.

Freshly ovulated mouse oocytes exposed to 5 mM calcium ionophore A23187 for 5 min and controls (not exposed) were cultured in TYH medium with 10 microg/ml puromycin (the puromycin group) or 2 mM 6-dimethylaminopurine (DMAP; the DMAP group) for 4 h. Among the controls, few oocytes were activated even if they were treated with DMAP or puromycin. In the oocytes exposed to A23187, in contrast, the activation rate, i.e. the rate of oocytes showing at least one pronucleus (PN) after the treatment, was 46.2% (48/104) in the DMAP group and 90.0% (118/131) in the puromycin group. Activation rate in the puromycin group was significantly higher than in the DMAP and control groups (p < 0.0001, respectively). Furthermore, 82.4% (108/131) of the activated oocytes in the puromycin group showed one PN with extrusion of the second polar body (PB). In the puromycin group, the DNA content of the PN of parthenogenones with 1PN2PB was half that of a set of metaphase II chromosomes. Chromosomal analysis was possible in 14 parthenogenones with 1PN2PB in the puromycin group. The parthenogenones possessed a normal set (n = 20) of haploid chromosomes. The combination of A23187 and puromycin proved to be an effective method of producing haploid parthenogenones.

Animals↗
PubMed2000

Effects of preservation of mouse spermatozoa in electrolyte-free solution at 4 degrees C on the outcome of mouse in vitro fertilization.

PURPOSE: The aim was to assess the fertilizing capacity of spermatozoa cool-preserved in electrolyte-free (EF) solution. METHODS: Mouse spermatozoa were cool-preserved in EF solution and the acrosomal status of the spermatozoa was compared before and after preservation using chlortetracycline stain. Mouse oocytes were inseminated by spermatozoa cool-preserved in EF solution for 2, 4, or 7 days and fertilization and blastocyst rates were evaluated. RESULTS: Acrosomal status of spermatozoa cool-preserved in EF solution was not different from spermatozoa before preservation, but the capacitated and acrosome-reacted spermatozoa significantly increased after reinitiation. Cool-preservation in EF solution for up to 4 days did not affect fertilization rate. Blastocyst rate of embryos derived from spermatozoa cool-preserved for 4 or 7 days in EF solution was significantly lower than that of embryos derived from fresh spermatozoa. CONCLUSIONS: Mouse spermatozoa cool-preserved in EF solution possesses as much fertilizing capacity as fresh spermatozoa. However, prolonged preservation affects the embryonic development.

Acrosome Reaction↗
PubMed2000

Production and regulation of cytokine-induced neutrophil chemoattractant in rat ovulation.

A cytokine-induced neutrophil chemoattractant (CINC/gro), which belongs to the interleukin (IL)-8 family, acts as a functional chemoattractant for neutrophils in rats. In the present study, we examined whether CINC/gro contributes to the ovulation process in the rat ovulation system. In rat ovaries, CINC/gro was immunohistochemically recognized in the theca layer of the antral follicle but not in the granulosa cells. To clarify the role of CINC/gro in the ovulation process, CINC/gro protein and mRNA were examined during pregnant mare serum gonadotropin (PMSG)-hCG treatment. CINC/gro protein did not increase as a result of PMSG injection. However, it increased rapidly after hCG injection and peaked at 6 h after hCG. CINC/gro mRNA was also strongly expressed after hCG injection. The increase of CINC/gro protein followed increases in IL-1beta and tumor necrosis factor alpha (TNFalpha). In the whole ovarian dispersate culture, FSH, hCG, IL-1beta, and TNFalpha stimulated the production of CINC/gro protein in a dose-dependent manner. In particular, the stimulatory effects of IL-1beta and TNFalpha were stronger than those of gonadotropins. These results suggest that CINC/gro plays an important role in the rat ovulation process by attracting neutrophils. CINC/gro increased just prior to ovulation, and it may be regulated directly by cytokines such as IL-1beta and TNFalpha and indirectly by gonadotropins.

Animals↗
PubMed2000

Dimeric inhibin A as a fourth marker for Down's syndrome maternal serum screening in native Japanese women.

OBJECTIVE: This study was conducted to assess the usefulness of dimeric inhibin A as a fourth marker for Down's syndrome screening in addition to AFP, hCG and uE3 markers for native Japanese women. METHODS: Serum specimens from 367 native Japanese women in the second trimester were assayed for dimeric inhibin A levels. Day specific dimeric inhibin A medians were established for gestational ages 15.0-21.9. Weekly median values for the native Japanese were compared with those of a U.S. population. Selected Japanese specimens from 15 diagnosed Down's syndrome and 3 trisomy 18 cases were also assayed for dimeric inhibin A. RESULTS: Dimeric inhibin A levels did not vary greatly over the gestational age range as expected. Median value comparison showed that native Japanese dimeric inhibin A medians are higher than the U.S. population medians by an average of 7.95%. Native Japanese dimeric inhibin A median values in this study are 1.77 times higher in Down's syndrome cases than in unaffected pregnancies. Trisomy 18 dimeric inhibin A levels show no significant difference from the unaffected pregnancies. CONCLUSIONS: This report shows for the first time that dimeric inhibin A can be informative as a fourth marker for Down's syndrome screening in native Japanese women. We expect the addition of dimeric inhibin A to a triple marker protocol will increase the accuracy of predicted risk for all pregnancies screened and increase the detection rate of Down's syndrome affected pregnancies.

Biomarkers↗
PubMed2000

Triple marker screening for trisomy 21, trisomy 18 and open neural tube defects in singleton pregnancies of native Japanese pregnant women.

OBJECTIVE: To report the results of prenatal triple marker screening on a population of Japanese pregnant women. METHODS: From April 1994 through March 1999, a total of 32,925 native Japanese women with singleton pregnancies requested a triple marker-screening test. Multiples of the median values for 3 markers and individual risks for each patient were calculated following adjustment for the Japanese weight correction factor. The risk cut-off values used for Down syndrome (T21), open spina bifida (OSB) and trisomy 18 (T18) were 1: 295, 1: 290, and 1: 100, respectively. Follow-up information was collected postpartum and statistically analyzed. RESULTS: Detection rates (DR) of T21 for women less than 35 years, over 35 years and overall were 58, 94, and 83%, respectively. DR of T18 for women less than 35 years, over 35 years and overall were 75, 79, and 79%, respectively. DR of open neural tube defects (ONTD) was 100%. CONCLUSIONS: The first cumulative data of an intervention program and prospective follow-up studies in Japan have proven to be similar to other published reports. Individual risk values were calculated for each pregnancy for T21, T18 and ONTD. This screening program is more effective than age-dependent screening for detecting T21, T18 and ONTD pregnancies.

Adult↗
PubMed2000

Serum leptin profiles in the normal menstrual cycles and gonadotropin treatment cycles.

Circulating levels of leptin, estradiol (E(2)) and progesterone (P(4)) throughout normal menstrual cycles (n = 13), and controlled, stimulated cycles (n = 33) were examined using sensitive specific radioimmunoassays in order to investigate the relationships between sex hormones (E(2), P(4)). Serum leptin levels during the normal menstrual cycle remained constant. However, in the ovulation induction cycle, E(2) levels and circulating leptin levels increased in parallel with the process of stimulation. In addition, leptin/body mass index ratios for all samples were significantly correlated with log(10)E(2). We conclude that particularly high levels of E(2) may have an effect on the secretion of leptin from adipose tissue.

Adult↗
PubMed2000

Activation of Ca2+-activated K+ channels in human myometrium by nitric oxide.

To investigate the mechanism of human uterine smooth muscle relaxation, the activation of Ca2+-activated K+ channels in cultured myometrial cells obtained from human pregnant myometrium at term by nitric oxide was evaluated at the single cell level using the patch-clamp technique. The open probability of the K+ channel after the addition of 3 x 10(-3) M isosorbide dinitrate, a nitric oxide donor (0.116 +/- 0.048) was significantly higher than that before the addition (0.059 +/- 0.032; n = 9, p < 0.01). In myometrial cells pretreated with lipopolysaccharide, activation of K+ channels was also noted after the addition of L-arginine (10(-4) M; open probability increased from 0.179 +/- 0.076 to 0.380 +/- 0.105, n = 9, p < 0.01: 10(-3) M; open probability increased from 0.073 +/- 0.050 to 0.242 +/- 0.098, n = 12, p < 0.01). Either 10(-3) M N-nitro-L-arginine-methyl-ester, an inhibitor of nitric oxide synthase, or 10(-6) M methylene blue, an inhibitor of guanylate cyclase, abolished activation of the K+ channel by 10(-3) M L-arginine in pretreated myometrial cells with lipopolysaccharide. Application of 10(-3) M L-arginine to the intracellular surface of an excised inside-out patch in the myometrial cells pretreated with lipopolysaccharide failed to increase Ca2+-activated K+ channel activity, suggesting that the activation was mediated by intracellular messengers. These results indicate that nitric oxide should control human myometrial relaxation during pregnancy via activation of Ca2+-activated K+ channels.

Arginine↗