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21.
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   
22.
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   
23.
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   
24.
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   
25.
Thymic carcinoma is a rare tumor. The most common histological subtype is squamous cell carcinoma, and only a few cases of thymic adenocarcinoma have been reported. A case of papillary adenocarcinoma of thymic origin that coexisted with type AB thymoma as a separate nodule is presented herein. The patient was found to have an abnormal mediastinal shadow on chest X-ray. A computed tomography scan revealed a round, 6.5-cm-diameter mass in the right anterior mediastinum. The preoperative diagnosis was thymoma, and thymothymectomy was performed. On pathological examination, two tumors, which were diagnosed as papillary adenocarcinoma and type AB thymoma, respectively, were present in the thymus without any connection with each other. The patient has been alive without any signs of recurrence for 11 years after surgery. We diagnosed the adenocarcinoma in this case was a primary thymic carcinoma.  相似文献   
26.
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   
27.
BACKGROUND: Sepsis is an arginine-deficient state and is associated with overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). It has been indicated that low plasma levels of arginine are related to high mortality rates in sepsis. Arginine, however, is also known to be a precursor of NO. Therefore, administration of arginine in septic patients remains controversial. We examined the effects of co-administration of arginine and aminoguanidine, a selective iNOS inhibitor, on sepsis, using rat models. METHOD: Sepsis was induced in rats by cecal ligation and puncture (CLP). Effects of separate and combined administration of arginine and aminoguanidine were investigated by comparing plasma levels of arginine, expressions of heme oxygenase (HO)-1 and HO-2 in liver and lung, and nitrite + nitrate (NOx) excretion in urine, as well as neuroendocrine responses in urine in the early phase of sepsis. Seven-day survival rates were also examined. RESULTS: A combination of arginine and aminoguanidine recovered the plasma level of arginine at 6 h post-CLP, decreased expression of HO-1 in liver and lung at 24 h post-CLP, decreased urinary excretion of epinephrine, norepinephrine, dopamine, and 17-hydroxycorticosteroid in the first 24 h post-CLP, and increased 7-d survival. CONCLUSION: It is demonstrated that administration of arginine together with the selective iNOS inhibitor in the early phase of sepsis restores plasma arginine, reduces oxidative stress by probably maintaining NO derived from constitutive NOS, and attenuates neuroendocrine stress responses. This co-administration may be a beneficial treatment approach against sepsis.  相似文献   
28.
Background Radiofrequency (RF) ablation for the treatment of the section line prior to liver resection has been proposed as a way to reduce blood loss during hepatectomy. Our group compared hepatectomy with and without RF ablation to determine whether this technique actually reduces blood loss during liver resection and whether it affects the perioperative outcome. Method Of 151 patients who underwent a hepatectomy between January 2002 and October 2005 at the Division of Gastrointestinal Surgery in the Department of Surgery of Saitama Medical University, 48 who had a partial hepatectomy or resection of a portion of liver smaller than a single Couinaud segment were included in the study. Twenty patients who had RF-assisted hepatectomy [RF (+) group] and 28 patients who had hepatectomy without ablation [RF (-) group] were studied to compare the rates of intraoperative blood loss and the effects of RF ablation on the perioperative outcome. Results Intraoperative blood loss was significantly reduced in the RF (+) group. In contrast, the alanine aminotransferase activity in the RF (+) group was significantly elevated immediately after the operation. There was no significant difference in the incidence of postoperative complications between the groups, although bile leakage did occur in three RF (+) patients. Conclusions Our results demonstrate that the RF ablation technique can be a useful way to reduce surgical blood loss. In view of its association with severe postoperative liver damage, the technique must be applied with caution. The danger may be especially relevant to patients with chronic liver disease and decreased liver reserve.  相似文献   
29.
BACKGROUND: In our institution, spinal anesthesia is the first choice for cesarean section. After the introduction of bupivacaine in 2000 in Japan, the intrathecal anesthetic agent shifted from tetracaine to bupivacaine. We analyzed the anesthesia for cesarean section in recent 7 years and compared the anesthetic quality of tetracaine with that of bupivacaine. METHODS: The anesthetic records were reviewed in the patients who had received cesarean section between January 1998 and December 2004 at our institution. RESULTS:There were 10456 deliveries during the study period with a cesarean section rate of 28.2% (2947 cases). Ninety-one percent of cesarean section was performed under spinal anesthesia. Spinal anesthetic agent shifted from tetracaine to bupivacaine in 2000-2001, both of which was prepared as a hyperbaric solution and supplemented with 0.1 mg of morphine hydrocloride. Of the 2711 patients in whom a cesarean section was started under spinal anesthesia, 20 (0.7%) required conversion to general anesthesia. Three hundred eighteen patients (11.7%) required some analgesic supplementation. The incidence of intra-operative analgesic supplementation was greater in the patients anesthetized with hyperbaric tetracaine and morphine than in those anesthetized with hyperbaric bupivacaine and morphine (22.96% vs 4.20% ; P<0.01). The conversion rate from spinal to general anesthesia for cesarean section was 0.7%. CONCLUSIONS: Comparing these two intrathecal anesthetic agents, the rate of analgesic supplementation in those anesthetized with bupivacaine was lower than in those anesthetized with tetracaine. This suggests that bupivacaine provides the more profound blockade of the visceral pain than tetracaine, and is superior as a local anesthetic.  相似文献   
30.
BACKGROUND: Renal urinary concentration is associated with enhanced expression of rBSC1, a rat sodium cotransporter, in the thick ascending limb of Henle. Increased expression of rBSC1 was reported recently in nephrogenic diabetes insipidus induced by lithium chloride (Li nephropathy). However, the pathophysiological implication of altered rBSC1 expression has not yet been investigated. METHODS: Li nephropathy was induced in rats by an oral administration of 40 mmol lithium/kg dry food. In rats with reduced urinary osmolality to less than 300 mOsm/kg H2O, we examined the expression of rBSC1 mRNA and protein, plasma arginine vasopressin (AVP) and RNA expression of kidney-specific water channel, aquaporin-2 (AQP2), of collecting ducts. Rats with Li nephropathy were treated with furosemide (3 mg/kg body weight), which blocks the activity of rBSC1, and changes in urine concentration, plasma AVP, medullary accumulation of Li ions, and apical AQP2 expression were determined. RESULTS: Rats with Li nephropathy showed increased rBSC1 RNA and protein expression and reduced AQP2 RNA. In these rats, furosemide, which induces dilution of urine and polyuria in normal rats, resulted in a progressive and significant rise in urine osmolality from 167 +/- 11 (mean +/- SD) at baseline to 450 +/- 45 mOsm/kg H2O at three hours after administration, and significant oliguria. In the same rats, plasma AVP decreased significantly from 5.7 to 3.0 pg/mL. In addition, recovery of apical AQP2 expression was noted in a proportion of epithelial cells of the collecting ducts. Although Li+ in the renal medulla was slightly lower in rats with Li nephropathy treated with furosemide, statistical significance was not achieved. CONCLUSIONS: Our results suggest that dehydration or high plasma AVP results in an enhanced rBSC1 expression in Li nephropathy, and that rBSC1 expression is closely associated with the adverse effects of Li ions on collecting duct function.  相似文献   
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