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571.
The risk of birth defects in dichorionic twins conceived by assisted reproductive technology. 总被引:1,自引:0,他引:1
Tomoyuki Kuwata Shigeki Matsubara Akihide Ohkuchi Takashi Watanabe Akio Izumi Yoko Honma Yukari Yada Hiroaki Shibahara Mitsuaki Suzuki 《Twin research》2004,7(3):223-227
The purpose of this study was to examine whether dichorionic twins conceived by assisted reproductive technology (ART; intracytoplasmic sperm injection [ICSI], in vitro fertilization [IVF], gamete-intrafallopian tube transfer [GIFT]) have a higher risk of birth defects compared to dichorionic twins conceived naturally. We reviewed the medical records of 406 mothers with dichorionic twin pregnancies, who received continuous antenatal care from < or = 20 weeks of gestation and gave birth to infants after > or = 24 weeks of gestation in our institute. Birth defects were diagnosed at the time of hospital discharge according to the International Classification of Diseases, 10th Revision. Occurrence of birth defects was compared between twins conceived by ART and those conceived naturally using logistic regression analysis. Overall, 51 of 812 infants (51/812 = 6.2%) had birth defects. The incidence of birth defects in ART-conceived twins was significantly higher than that of naturally conceived twins with an odds ratio of 6.9 (95% confidence interval [CI] 2.1, 22.5), 3.7 (95% CI 1.2, 12.0), and 4.3 (95% CI 1.4, 14.3) for ICSI, IVF, and GIFT, respectively. The higher frequency of birth defects in ART-conceived twins was still significant after adjusting for higher maternal age in the ART group, with an adjusted odds ratio of 6.7 (95% CI 2.1, 21.9), 3.6 (95% CI 1.1, 11.5), and 3.7 (95% CI 1.2-11.8) for ICSI, IVF, and GIFT, respectively. Dichorionic twins conceived by ART, compared to dichorionic twins conceived naturally, had a much higher risk for birth defects diagnosed at hospital discharge. 相似文献
572.
Yamasaki M Tachibana H Yamada A Ochi Y Madhyastha H Nishiyama K Yamada K 《In vitro cellular & developmental biology. Animal》2008,44(7):290-294
Our previous study indicated that oleic acid prevented apoptotic cell death induced by trans10, cis12 (t10, c12)-conjugated linoleic acid in rat hepatoma dRLh-84 cells. The intracellular mechanism of action oleic acid is still unknown. Here, we showed that p38 mitogen-activated protein kinase (MAPK) inhibition using its specific inhibitor SB203580 cancelled the ameliorative effect of oleic acid on the cytotoxicity of t10, c12-conjugated linoleic acid. In addition, SubG1 cell population analysis showed that p38 MAPK played an essential role in the prevention of apoptotic cell death by oleic acid. In fact, p38 phosphorylation level was upregulated in cells treated with oleic acid irrespective of t10, c12-conjugated linoleic acid stimulation. Interestingly, t10, c12-conjugated linoleic acid increased intracellular triglyceride accumulation. However, oleic acid completely inhibited this effect. These observations indicated the involvement of blockade of a p38 MAPK pathway in the ameliorative effect of oleic acid on apoptosis induced by t10, c12-conjugated linoleic acid. 相似文献
573.
Root canal antiseptics are topically applied to root canals within the pulpless teeth to treat the root canal and periapical infections. Because the antiseptics that are applied to root canals can penetrate through dentin or leak out through an apical foramen into the periodontium and distribute by the systemic circulation, it is important to study the safety of these antiseptics. In the present study, we examined the ability to induce chromosome aberrations in human dental pulp cells of five root canal antiseptics, namely, carbol camphor (CC), camphorated p-monochlorophenol (CMCP), formocresol (FC), calcium hydroxide, and iodoform which are most commonly used in dental practice. Statistically significant increases in the levels of chromosome aberrations were induced by CC, FC, or iodoform in a concentration-dependent manner. Conversely, CMCP and calcium hydroxide failed to induce chromosome aberrations in the absence or presence of exogenous metabolic activation. The percentages of cells with polyploid or endoreduplication were enhanced by FC or iodoform. Our results indicate that the root canal antiseptics that exhibited a positive response are potentially genotoxic to human cells. 相似文献
574.
For group-living animals, discriminating among individuals and chasing unfamiliar strangers away from the home range are important to protect their territory. Previously, we reported that the familiar individual information conveyed by urine results in less aggressive behavior by resident male mice toward intruders. A resident male is aggressive toward an intruding unfamiliar castrated C57BL/6J mouse (unfamiliar castrated male [UFC]), whereas there is less aggression by the resident male when the UFC is swabbed with urine collected from the resident's cage mate. Urine is affected by various factors, including the environment. In this study, we investigated the effect of 2 living environments, the early developmental environment and the adult diet, on individual information conveyed in urine. Aggressive behavior toward UFCs was lower when UFCs were swabbed with cage mate urine or urine from a cage mate's littermate that was not living with the resident male (UFCL). Litters were cross-fostered, and we examined whether the pre- or postnatal period was important for formation of individual urine odor. The resident male displayed attack bites toward UFCs that were his cage mate's littermates but were fostered by another C57BL/6J dam. In addition, a castrated male that was reared with a cage mate (sharing the same postnatal environment) but that was not his littermate was also attacked by the resident male, suggesting that littermates that share the same pre- and postnatal environments provide similar (or identical) information, which inhibits aggression. In adulthood, even after dietary changes, the resident male showed less aggression toward UFCs when the UFCs were swabbed with the cage mate's urine, which was collected before a dietary change, indicating that individual information was not affected by dietary conditions in adulthood. In a habituation-dishabituation test, resident mice could discriminate among all pairs of mouse urine from each group. These results suggest that olfactory cues containing individual information are shared among littermates, and both the pre- and postnatal environments are important for formation of the information that inhibits aggressive behavior. This individual information might differ from the odor that is used for discriminating in the habituation-dishabituation test. 相似文献
575.
Ito S Satoh A Nagatomi Y Hirata Y Suzuki G Kimura T Satow A Maehara S Hikichi H Hata M Kawamoto H Ohta H 《Bioorganic & medicinal chemistry》2008,16(22):9817-9829
We describe here the discovery and the structure-activity relationship (SAR) of a series of 4-(1-Aryltriazol-4-yl)-tetrahydropyridines as novel mGluR1 antagonists. Our extensive chemical modification of lead compound 2 successfully led to fluoropyridine analogs 7j and 1 with improved in vivo antagonistic activities. Among the evaluated compounds, chemically stable urea analog 1 showed oral antagonistic activity at dose ranges of 10-30mg/kg in an animal model. 相似文献
576.
Wada A Matsuura N Mizuguchi Y Nakagawa K Ito M Okano T 《Bioorganic & medicinal chemistry》2008,16(18):8471-8481
Various 5-substituted retinoic acids were prepared by a palladium-catalyzed cross coupling reactions of vinyl nonaflates and E- or Z-3-tributylstannyl-2-beten-1-ol as a key reaction. These coupling products were then converted to the corresponding all-E- and 9Z-retinoic acid analogs via Horner-Emmons reaction and subsequent basic hydrolysis, and their biological activities were evaluated. The all-E-derivatives, 5-butyl and isobutyl analogs exhibited stronger effects for anti-proliferative and differentiation-inducing activities in HL-60 cells. In contrast, in 9Z-derivatives, none of the analogs showed any activity. 相似文献
577.
Komano T Egashira Y Sanada H 《Biochemical and biophysical research communications》2008,372(4):688-690
d-Galactosamine (GalN) induces acute hepatitis in experimental animals and this hepatitis has been shown to be suppressed by preceding ingestion of amino acids such as Gly, l-Ser, and l-Gln. However, little is known about the mechanism of its action. The present study shows for the first time that IL-18 reduction is involved in the suppressive actions of l-Gln and l-Ser on GalN-induced hepatitis. Elevation of IL-18 mRNA expression in liver and its concentration in serum in GalN-treated rats were found to be suppressed by preceding ingestion of 10% l-Gln- or 10% l-Ser diets, and resulted in the attenuation of the increase in serum transaminase (ALT and AST) activities, indexes of hepatic injury. These results suggest that suppressive effects of some dietary amino acids on the GalN-induced hepatitis are mediated by IL-18 reduction. 相似文献
578.
Sasaki Y Sone T Yahata K Kishine H Hotta J Chesnut JD Honda T Imamoto F 《Journal of biotechnology》2008,136(3-4):103-112
Two types of eukaryotic operon-type Expression clones were constructed using the Multisite Gateway system employing six types of att signals. These clones harbored a DNA cassette containing two heterologous ORFs (cDNAs) or three heterologous ORFs in tandem downstream of a single promoter. The most promoter-proximal ORF was translated via a Kozak signal and the downstream one or two ORF(s) were translated as directed by internal ribosome entry site(s) (IRES). These clones were observed to produce two or three different proteins at levels that depended on the activities of the translational initiation signals used. With the intention of modulating the expression level of the first ORF, the translational initiation signals including a Kozak sequence and 11 different IRESs were investigated for their efficiency using a single ORF. The translational activity of these signals varied within a 10-fold magnitude. Using these results, expression at pre-described relative levels was achieved from the optional IRES of the respective ORFs in the cassette. Controllable expression at desired levels of two different ORFs directed by optional IRESs on a bicistronic construct, transcribed from a single promoter, was demonstrated. 相似文献
579.
Ichiro Yasuhi Tomoko Soda Hiroshi Yamashita Atsuko Urakawa Mihoko Izumi Yukari Kugishima Yasushi Umezaki 《International breastfeeding journal》2017,12(1):32
Background
Although breastfeeding is expected to reduce the incidence of diabetes in women with gestational diabetes, the effect has not been clearly confirmed. We examined whether or not high-intensity breastfeeding reduces the incidence of abnormal glucose tolerance and investigated the effect of high-intensity breastfeeding on insulin resistance during the first year postpartum in Japanese women with current gestational diabetes.Methods
In this retrospective study, we included women with gestational diabetes who underwent postpartum 75 g oral glucose tolerance test during the first year (12-14 months) postpartum from 2009 to 2011 at a single tertiary perinatal care center in Japan. High-intensity breastfeeding was defined as the condition in which infants were fed by breastfeeding alone or 80% or more of the volume. We investigated the effect of high-intensity breastfeeding on the prevalence of postpartum abnormal glucose tolerance and the postpartum homeostasis model of assessment of insulin resistance (HOMA-IR), after controlling for confounders, including prepregnancy obesity and weight changes during pregnancy and postpartum.Results
Among 88 women with gestational diabetes, 46 (52%) had abnormal glucose tolerance during the postpartum period. High-intensity breastfeeding women (n?=?70) were significantly less likely to have abnormal glucose tolerance than non-high-intensity breastfeeding women (n?=?18) (46% vs. 78%, p?=?0.015). High-intensity breastfeeding was also associated with a lower HOMA-IR at 12-14 months postpartum than non-high-intensity breastfeeding (1.41?±?1.02 vs. 2.28?±?1.05, p?=?0.035). Those associations remained significant after controlling for confounders. At least six months of high-intensity breastfeeding had a significant effect on lowering both the abnormal glucose tolerance prevalence and HOMA-IR compared with non-high-intensity breastfeeding.Conclusions
In Japanese women with gestational diabetes, high-intensity breastfeeding ≥6 months had a protective effect against the development of abnormal glucose tolerance during the first year postpartum through improving insulin resistance, independent of obesity and postpartum weight change.580.
Hatada Y Takeda N Hirasawa K Ohta Y Usami R Yoshida Y Grant WD Ito S Horikoshi K 《Extremophiles : life under extreme conditions》2005,9(6):497-500
A novel alkaline mannanase Man26A has been found in the culture of an alkaliphilic Bacillus sp. strain JAMB-750 and the optimal pH for the mannanase activity of the enzyme was around pH 10 (J Biol Macromol 4: 67–74, 2004). This optimal pH is the highest among those of the mannanases reported to date. The gene man26A coding the enzyme was cloned from the genomic DNA of strain JAMB-750 and sequenced. It encodes a protein of 997 amino acids including a signal peptide. The N-terminal half (Glu27–Val486) of the enzyme exhibited moderate similarities to other mannanases belonging to glycoside hydrolase family 26, such as the enzymes from Cellvibrio japonicus (37% identity), Cellulomonas fimi (33% identity), and Bacillus sp. strain AM-001 (28% identity). The C-terminal half was found to contain four domains. The first, second, third, and fourth domains exhibited similarities to the carbohydrate-binding module, the mannan-binding module, the Homo sapiens collagen type IX alpha I chain, and the membrane anchor region of Gram-positive surface proteins, respectively. Its recombinant mannanase was produced extracellularly using Bacillus subtilis as the host. The optimal pH for the mannanase activity of the recombinant enzyme was around pH 10. The enzyme was very resistant to surfactants, for example, SDS up to 2.0% (w/v). 相似文献