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31.
Ai Tsuji Yuka Ikeda Mutsumi Murakami Yasuko Kitagishi Satoru Matsuda 《Nutrition Research And Practice》2022,16(3):314
BACKGROUND/OBJECTIVESOocyte lipid droplets play a crucial role in meiosis and embryo development. Biotin is associated with fatty acid synthesis and is the coenzyme for acetyl-CoA carboxylase (ACC). The effects of a biotin deficiency on the oocyte lipid metabolism remain unknown. This study examined the effects of a biotin deficiency and its replenishment on murine 1) oocyte lipid droplet levels, 2) ovary lipid metabolism, and 3) oocyte meiosis.MATERIALS/METHODSMice were divided into 3 groups: control, biotin deficient (BD), and recovery groups. The control and BD groups were fed a control diet or BD diet (0.004 or 0 g biotin/kg), respectively. The recovery group mice were fed a BD diet until day 21, and were then fed the control diet from days 22 to 64. This study then quantified the oocyte lipid droplet levels, assessed the oocyte mitochondrial function, and examined the ability of oocytes to undergo meiosis. Ovarian phosphorylated ACC (p-ACC), lipogenesis, β-oxidation, and ATP production-related genes were evaluated.RESULTSThe BD group showed a decrease in lipid droplets and mitochondrial membrane potential and increased p-ACC levels. In the recovery group, the hepatic biotin concentration, ovarian p-ACC levels, and mitochondrial membrane potential were restored to the control group levels. On the other hand, the quantity of lipid droplets in the recovery group was not restored to the control levels. Furthermore, the percentage of oocytes with meiotic abnormalities was higher in the recovery group than in the control group.CONCLUSIONSA biotin deficiency reduced the oocyte lipid droplet levels by downregulating lipogenesis. The decreased lipid droplets and increased oocyte meiosis failure were not fully restored, even though the biotin nutrition status and gene expression of lipid metabolism was resumed. These results suggest that a biotin deficiency remains robust and can be long-lasting. Biotin might play a crucial role in maintaining the oocyte quality. 相似文献
32.
As part of a Hastings Center Report series of six articles on reproductive technologies around the world, three Japanese scholars report on the situation in their country. At present, artificial insemination and in vitro fertilization are offered to infertile married couples, and research is performed on early embryos up to 14 days after fertilization. Neither surrogate mothers nor donated gametes are used in Japan. Bai, Shirai, and Ishii identify several issues that they believe merit further public debate, among them the legal status of AID children, the experimental nature of in vitro fertilization, genetic manipulation of embryos, and gender selection. They summarize the findings of four opinion surveys that show a lack of consensus among the Japanese on the acceptability of reproductive technologies, which in the words of the authors "create a tension and a link between traditional belief and contemporary practice." 相似文献
33.
Shigeharu Ohyu Mitsuhiro Tozaki Michiro Sasaki Hisae Chiba Qilin Xiao Yasuko Fujisawa Yoshiaki Sagara 《Magnetic resonance in medical sciences》2022,21(3):485
Purpose: We evaluated the diagnostic performance of the texture features of dynamic contrast-enhanced (DCE) MRI for breast cancer diagnosis in which the discriminator was optimized, so that the specificity was maximized via the restriction of the negative predictive value (NPV) to greater than 98%.Methods: Histologically proven benign and malignant mass lesions of DCE MRI were enrolled retrospectively. Training and testing sets consist of 166 masses (49 benign, 117 malignant) and 50 masses (15 benign, 35 malignant), respectively. Lesions were classified via MRI review by a radiologist into 4 shape types: smooth (S-type, 34 masses in training set and 8 masses in testing set), irregular without rim-enhancement (I-type, 60 in training and 14 in testing), irregular with rim-enhancement (R-type, 56 in training and 22 in testing), and spicula (16 in training and 6 in testing). Spicula were immediately classified as malignant. For the remaining masses, 298 texture features were calculated using a parametric map of DCE MRI in 3D mass regions. Masses were classified into malignant or benign using two thresholds on a feature pair. On the training set, several feature pairs and their thresholds were selected and optimized for each mass shape type to maximize specificity with the restriction of NPV > 98%. NPV and specificity were computed using the testing set by comparison with histopathologic results and averaged on the selected feature pairs.Results: In the training set, 27, 12, and 15 texture feature pairs are selected for S-type, I-type, and R-type masses, respectively, and thresholds are determined. In the testing set, average NPV and specificity using the selected texture features were 99.0% and 45.2%, respectively, compared to the NPV (85.7%) and specificity (40.0%) in visually assessed MRI category-based diagnosis.Conclusion: We, therefore, suggest that the NPV of our texture-based features method described performs similarly to or greater than the NPV of the MRI category-based diagnosis. 相似文献
34.
Murata T Miyase T Muregi FW Naoshima-Ishibashi Y Umehara K Warashina T Kanou S Mkoji GM Terada M Ishih A 《Journal of natural products》2008,71(2):167-174
From the stem bark of Ekebergia capensis, 10 new triterpenoid compounds, ekeberins A (1), B (2), C1 (3), C2 (4), C3 (5), D1 (6), D2 (7), D3 (8), D4 (9), and D5 (10), were isolated together with 17 known compounds. The structures of these new compounds were elucidated on the basis of the results of spectroscopic analysis, and the absolute configuration of compounds 6-10 were determined by partial synthesis from known compounds and using the Mosher ester method. Several of these compounds were screened in vitro against both chloroquine (CQ)-sensitive and -resistant Plasmodium falciparum isolates and were found to exhibit moderate antiplasmodial activity, with compounds 20 (7-deacetoxy-7-oxogedunin) and 27 (2-hydroxymethyl-2,3,22,23-tetrahydroxy-2,6,10,15,19,23-hexamethyl-6,10,14,18-tetracosatetraene) showing IC50 values of 6 and 7 microM, respectively. Compound 27 at a dose of 500 mg/kg showed moderate parasitemia suppression of 52.9% against P. berghei NK 65 in a mouse model. 相似文献
35.
Breech presentation occurs at term in approximately 3% to 4% of singleton gestations. This presentation is associated with a variety of maternal and fetal conditions including preterm labor, abnormal amniotic fluid volume, hydrocephaly, anencephaly, mullerian anomalies, abnormal placentation, and multifetal gestation. Cesarean delivery has been associated with increased risk of subsequent accreta, placenta previa, hemorrhage, and hysterectomy. The Term Breech Trial initially suggested that planned vaginal breech delivery is associated with increased neonatal morbidity and mortality compared with planned cesarean delivery. Long-term follow-up of these vaginally delivered infants contradict the initial findings. Current debate surrounds the dilemma of whether the untoward complications of cesarean delivery are warranted given uncertain minimal increases in neonatal survival and improvement in neurologic outcome with planned cesarean. 相似文献
36.
Tsuchiya Y Ubara Y Suwabe T Hoshino J Sumida K Hiramatsu R Hasegawa E Yamanouchi M Hayami N Marui Y Sawa N Takemoto F Takaichi K 《Clinical and experimental nephrology》2011,15(3):434-437
Acute promyelocytic leukemia (APL) has the best prognosis among acute leukemias, but there is little data about APL in patients on hemodialysis. A 64-year-old hemodialysis patient was successfully treated for APL by induction therapy with all-trans retinoic acid (ATRA), three courses of consolidation therapy with Ara-C, mitomycin?C (MIT), daunorubicin (DNR), and idarubicin (IDR), and maintenance therapy with ATRA. Complete remission has been maintained for 42?months in this patient. With dose modification, ATRA and chemotherapy may be safely given to patients on hemodialysis. 相似文献
37.
Baicalein, a component of Scutellaria radix from Huang-Lian-Jie-Du-Tang (HLJDT), leads to suppression of proliferation and induction of apoptosis in human myeloma cells 总被引:6,自引:0,他引:6 下载免费PDF全文
Ma Z Otsuyama K Liu S Abroun S Ishikawa H Tsuyama N Obata M Li FJ Zheng X Maki Y Miyamoto K Kawano MM 《Blood》2005,105(8):3312-3318
In the search for a more effective adjuvant therapy to treat multiple myeloma (MM), we investigated the effects of the traditional Chinese herbal medicines Huang-Lian-Jie-Du-Tang (HLJDT), Gui-Zhi-Fu-Ling-Wan (GZFLW), and Huang-Lian-Tang (HLT) on the proliferation and apoptosis of myeloma cells. HLJDT inhibited the proliferation of myeloma cell lines and the survival of primary myeloma cells, especially MPC-1- immature myeloma cells, and induced apoptosis in myeloma cell lines via a mitochondria-mediated pathway by reducing mitochondrial membrane potential and activating caspase-9 and caspase-3. Further experiments confirmed that Scutellaria radix was responsible for the suppressive effect of HLJDT on myeloma cell proliferation, and the baicalein in Scutellaria radix showed strong growth inhibition and induction of apoptosis in comparison with baicalin or wogonin. Baicalein as well as baicalin suppressed the survival in vitro of MPC-1- immature myeloma cells rather than MPC-1+ myeloma cells from myeloma patients. Baicalein inhibited the phosphorylation of IkB-alpha, which was followed by decreased expression of the IL-6 and XIAP genes and activation of caspase-9 and caspase-3. Therefore, HLJDT and Scutellaria radix have an antiproliferative effect on myeloma cells, especially MPC-1- immature myeloma cells, and baicalein may be responsible for the suppressive effect of Scutellaria radix by blocking IkB-alpha degradation. 相似文献
38.
Nakao M Horiike S Fukushima-Nakase Y Nishimura M Fujita Y Taniwaki M Okuda T 《British journal of haematology》2004,125(6):709-719
39.
40.
Pseudohypoparathyroidism type Ia (PHP-Ia), one of 4 types of PHP, is a genetic disease characterized by clinical hypoparathyroidism caused by parathyroid hormone (PTH) resistance. In addition, patients with PHP-Ia show resistance to other hormones as well as Albright's hereditary osteodystrophy (AHO), a constellation of features including short stature, obesity, brachydactyly, ectopic ossifications, and/or mental retardation. Hypocalcemia is one of the hallmarks of PHP-Ia, but several PHP-Ia patients have been described to have normocalcemia. We encountered a 10-year-old girl with typical Albright's hereditary osteodystrophy with round face, short stature, brachydactyly, and obesity. Biochemical examination showed normocalcemia and increased PTH levels. Ellsworth-Howard test did not show any responses of urinary cAMP and phosphate. Based on these findings, she was diagnosed as having PHP-Ia with normocalcemia. Sequencing analysis of the GNAS gene identified a heterozygous missense mutation in exon 13 (R385H), which was previously reported in a PHP-Ia patient. The exact reason for her normocalcemia is not determined, but we must recognize heterogeneous biochemical findings even in PHP-Ia. 相似文献