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61.
Conjugated linoleic acid supplementation reduces adipose tissue by apoptosis and develops lipodystrophy in mice 总被引:47,自引:0,他引:47
Tsuboyama-Kasaoka N Takahashi M Tanemura K Kim HJ Tange T Okuyama H Kasai M Ikemoto S Ezaki O 《Diabetes》2000,49(9):1534-1542
Conjugated linoleic acid (CLA) is a naturally occurring group of dienoic derivatives of linoleic acid found in beef and dairy products. CLA has been reported to reduce body fat. To examine the mechanism(s) of CLA reduction of fat mass, female C57BL/6J mice were fed standard semipurified diets (10% fat of total energy) with or without CLA (1% wt/wt). Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick endlabeling (TUNEL) and DNA fragmentation analysis revealed that fat-mass decrease by CLA was mainly due to apoptosis. Tumor necrosis factor (TNF)-alpha and uncoupling protein (UCP)-2 mRNA levels increased 12- and 6-fold, respectively, in isolated adipocytes from CLA-fed mice compared with control mice. Because it is known that TNF-alpha induces apoptosis of adipocytes and upregulates UCP2 mRNA, a marked increase of TNF-alpha mRNA with an increase of UCP2 in adipocytes caused CLA-induced apoptosis. However, with a decrease of fat mass, CLA supplementation resulted in a state resembling lipoatrophic diabetes: ablation of brown adipose tissue, a marked reduction of white adipose tissue, marked hepatomegaly, and marked insulin resistance. CLA supplementation decreased blood leptin levels, but continuous leptin infusion reversed hyperinsulinemia, indicating that leptin depletion contributes to the development of insulin resistance. These results demonstrate that intake of CLA reduces adipose tissue by apoptosis and results in lipodystrophy, but hyperinsulinemia by CLA can be normalized by leptin administration. 相似文献
62.
Suzuki Kohta Kasai Tsuyoshi Suzuki Mariko Miyake Maki Fujie Michiko Mizuno Kaoruko Hirata Shuji Hoshi Kazuhiko 《Reproductive Medicine and Biology》2004,3(1):27-31
Background : In the summer of 2002, standard guidelines for the application of assisted reproductive technology were reported by a research group of the Ministry of Health, Labor and Welfare. The present study aimed to examine the relationship between the number of cycles of artificial insemination and the cumulative pregnancy rates according to the cause of infertility.
Methods : Patients who experienced their first cycle of artificial insemination during the period of January 1999–December 2002 were included in the study and were divided into a male factor infertility group and an idiopathic infertility group. Cumulative pregnancy rates resulting from artificial insemination with the husband's semen were calculated by the life-table approach.
Results : During the study period, 139 couples entered the assisted reproduction program and underwent 581 cycles. Significant differences were observed in cumulative pregnancy rates between the two groups.
Conclusion : It is recommended that couples with male factor infertility and who fail to conceive within six or seven cycles of intrauterine insemination, consider a modification of treatment strategy such as in vitro fertilization, because cumulative pregnancy rates of this group were reached at a plateau within six or seven cycles. In contrast, patients with idiopathic infertility, the cumulative pregnancy rates appeared to increase constantly with each subsequent cycle. It is important to consider modifications of treatment strategy in the light of the cause of infertility. (Reprod Med Biol 2004; 3 : 27–31) 相似文献
Methods : Patients who experienced their first cycle of artificial insemination during the period of January 1999–December 2002 were included in the study and were divided into a male factor infertility group and an idiopathic infertility group. Cumulative pregnancy rates resulting from artificial insemination with the husband's semen were calculated by the life-table approach.
Results : During the study period, 139 couples entered the assisted reproduction program and underwent 581 cycles. Significant differences were observed in cumulative pregnancy rates between the two groups.
Conclusion : It is recommended that couples with male factor infertility and who fail to conceive within six or seven cycles of intrauterine insemination, consider a modification of treatment strategy such as in vitro fertilization, because cumulative pregnancy rates of this group were reached at a plateau within six or seven cycles. In contrast, patients with idiopathic infertility, the cumulative pregnancy rates appeared to increase constantly with each subsequent cycle. It is important to consider modifications of treatment strategy in the light of the cause of infertility. (Reprod Med Biol 2004; 3 : 27–31) 相似文献
63.
Ohno T Ikebuchi E Henomatsu K Kasai K Nakagome K Iwanami A Hiramatsu K Hata A Fukuda M Honda M Miyauchi M 《Psychiatry research》2000,100(3):155-167
Social skill deficits in schizophrenia profoundly affect patients' life-long outcome, although the profile of the underlying cognitive dysfunction still remains a matter of debate. In the present study, we investigated the relationship between social skills and event-related potentials (ERPs) in an auditory selective attention task, in addition to the neurocognitive indices obtained from the degraded-stimulus continuous performance test (CPT) and clinical indices, such as Brief Psychiatric Rating Scale (BRPS) and global assessment of function (GAF) scores. Social skills were assessed using a Japanese version of the structured role play test. Fourteen persons with schizophrenia participated in the study. Non-verbal skills showed a positive correlation with GAF, the performance level, N1 and N2b amplitude in the ERP task, and hit rate in the CPT, and a negative correlation with reaction time in the CPT. Verbal communication skills showed a positive correlation with GAF, the performance level and N2b amplitude in the ERP task, and hit rate in the CPT, and a negative correlation with reaction time in the CPT. Processing skills showed a positive correlation with the performance level and N1 amplitude in the ERP task and a negative correlation with reaction time in the CPT. These findings suggested that the social skill deficits of persons with schizophrenia were related to the vigilance level and controlled stimulus detection processing. 相似文献
64.
Naito Y Yoshikawa T Matsuyama K Yagi N Kasai K Sugimoto N Masui Y Yoshida N Kondo M 《Alimentary pharmacology & therapeutics》1999,13(4):553-559
BACKGROUND: Neutrophil infiltration and lipid peroxide accumulation are involved in reperfusion-induced gastric mucosal injury in nitric oxide-depleted rats. AIM: To assess the effect of vitamin E on this injury. METHODS: After ischaemia-reperfusion, the total area of erosions, lipid peroxide contents in gastric mucosa, and gastric neutrophil accumulation were compared between nitric oxide-depleted rats with deficient, normal, and increased vitamin E intake over 8 weeks. Thiobarbituric acid-reactive substances and tissue-associated myeloperoxidase activity were measured in gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. RESULTS: The total area of erosions was significantly increased in the vitamin E-deficient group compared with the sufficient-intake and vitamin-supplemented groups. Both thiobarbituric acid-reactive substances and myeloperoxidase activity also were significantly increased in the vitamin E-deficient group compared with others. The total area of erosions closely paralleled the increases in both thiobarbituric acid-reactive substances and myeloperoxidase activity. CONCLUSION: These results indicate that the inhibition of lipid peroxidation and interference with neutrophil infiltration by vitamin E may be responsible for its cytoprotective effect in ischaemia-reperfusion. 相似文献
65.
Takeyama K Ogura M Morishima Y Kasai M Kiyama Y Ohnishi K Mitsuya H Kawano F Masaki Y Sasaki T Chou T Yokozawa T Tobinai K;Lenograstim/Lymphoma Study Group 《Japanese journal of clinical oncology》2003,33(2):78-85
BACKGROUND: Peripheral blood stem cell (PBSC) reinfusion has been widely used for hematopoietic reconstitution after high-dose chemotherapy. However, the optimal dose of granulocyte colony-stimulating factor (G-CSF) for PBSC mobilization in combination with chemotherapy for autograft remains unknown. METHODS: To find the optimal dose of glycosylated G-CSF (lenograstim) for PBSC mobilization in combination with chemotherapy for aggressive non-Hodgkin's lymphoma (NHL), we conducted a dose-finding study on 43 newly diagnosed patients who had unfavorable prognostic factors. They received four to six courses of cyclophosphamide, doxorubicin, vincristine and prednisolone combined with lenograstim every 2 weeks (biweekly CHOP therapy). PBSC apheresis was started after the third course of biweekly CHOP therapy. Lenograstim was given daily from day 3 until the day of the last apheresis. The optimum dose of lenograstim was assessed based on mobilization efficacy and safety profiles at a daily single dose of 2, 5 and 10 microg/kg for eight patients in each level. RESULTS: The collected number of CD34+ cells in the first apheresis products was higher in the 5 microg/kg group than in the 2 microg/kg group (median, 4.22 x 10(6) vs 2.49 x 10(6) CD34+ cells/kg, P = 0.051). The highest dose of 10 microg/kg (median, 2.99 x 10(6) CD34+ cells/kg) failed to show a dose dependence in PBSC mobilization. The efficacy and safety of the 5 microg/kg dose were further confirmed in an additional 19 patients. CONCLUSIONS: The present study suggests that the recommended dose of lenograstim for PBSC mobilization with CHOP therapy in untreated NHL is 5 microg/kg. 相似文献
66.
Ohara M Shimizu Y Satoh H Kasai T Takano S Fujiwara R Furusawa Y Kameda S Matsumura T Narimatsu H Kusumi E Kodama Y Kami M Murashige N Suzuki M 《The journal of obstetrics and gynaecology research》2008,34(2):189-194
AIM: Japan has a shortage of tertiary medical care facilities for maternal and fetal medicine. Establishment of efficient medical transport systems is needed for pregnant women and fetuses with severe complications. Maternal transport by helicopters is expected to shorten transportation time to advanced facilities, although its feasibility has not yet been evaluated. The aim of the present study was to investigate the status of maternal helicopter transport, and conditions of the pregnant patients and children transferred by helicopter to Kameda Medical Center (KMC). METHODS: Between August 2005 and July 2006, 26 pregnant women were transported by helicopters to KMC. RESULTS: The median net flight time was 24 min (range 15-29 min), and the median of estimation of ground transportation time was 125 min (range 90-180 min). The causes for transfers were preterm labor in eight, preterm premature rupture of the membrane in five, cervical incompetence in five, pre-eclampsia in three and other medical reasons in five. Five of the 26 patients were discharged with restored stability of pregnancy. The remaining 21 patients underwent delivery at KMC. The median gestational age was 26 weeks (range 22-33 weeks) at the time of transfer and 31 weeks (range 22-37 weeks) at delivery. Four of 26 neonates who were born at KMC died after birth due to severe premature or congenital anomaly. Seventeen of the remaining 22 neonates, including 10 twins, received treatment in the neonatal intensive care unit. All of the 22 neonates and all the mothers were discharged in good condition. No patients developed any complications requiring treatment during flights. CONCLUSION: Helicopter transfer is feasible for pregnant patients with severe complications. 相似文献
67.
Yinghan Zhu Hironori Nakatani Walid Yassin Norihide Maikusa Naohiro Okada Akira Kunimatsu Osamu Abe Hitoshi Kuwabara Hidenori Yamasue Kiyoto Kasai Kazuo Okanoya Shinsuke Koike 《Schizophrenia bulletin》2022,48(3):563
Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier. 相似文献
68.
Hiroaki Sato Kentaro Kasai Toshiko Tanaka Toshiro Kita Noriyuki Tanaka 《Medical science monitor》2008,14(5):BR79-BR87
BACKGROUND: Hemorrhagic shock occasionally causes a fatal outcome following an outbreak of lung dysfunction, but the precise mechanism has not been clearly elucidated. Several studies have indicated that hemorrhagic shock causes a delayed vascular inflammatory decompensation and leads to inflammation-related organ dysfunction. Tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta are known as major proinflammatory cytokines that play an important role in excessive autolytic inflammation, finally inducing organ dysfunctions. In this study, the role of TNF-alpha and IL-1beta on lung dysfunction following hemorrhagic shock was examined by using FR167653, a potent inhibitor of TNF-alpha and IL-1beta production that acts by suppressing p38 mitogen-activated protein kinase (MAPK). MATERIAL/METHODS: Hemorrhagic shock was induced in anesthetized male rats by bleeding via a common carotid catheter for 20 minutes to 25% of total body blood volume without fluid resuscitation. Mean blood pressure, heart rate and arterial blood gas components were recorded up to 5 hours after the bleeding. The levels of TNF-alpha, IL-1beta and lactic dehydrogenase (LDH)-3 isozyme were measured in the serum of pulmonary venous blood. The lung tissue was excised for the assay of mRNA and for histopathological study. RESULTS: The expressions of mRNA for TNF-alpha and IL-1beta in the lung tissue and the concentrations of both cytokines in pulmonary serum increased after a hemorrhage. Inflammation-related injuries and function deterioration were observed in the lung following hemorrhagic shock. These hemorrhagic changes were inhibited by pretreatment with FR167653. CONCLUSIONS: TNF-alpha and IL-1beta play a key role in the development of inflammation-related lung dysfunction following hemorrhagic shock. Our model should be useful to explain the pathogenesis of lung dysfunction following hemorrhagic shock. 相似文献
69.
Target site insensitivity because of mutations in the voltage‐sensitive sodium channel gene (Vssc) is a major mechanism of resistance to pyrethroid insecticides in the house fly, Musca domestica. There are three known Vssc alleles that confer resistance to pyrethroids in the house fly: knock down resistance (kdr; L1014F), super‐kdr (M918T + L1014F) and kdr‐his (L1014H), but there has been no side‐by‐side comparison of the resistance levels that they confer. We compared the levels of resistance conferred by the three Vssc alleles in congenic strains to 19 structurally diverse pyrethroids, and compared the full‐length Vssc cDNA sequences from each strain. Generally, the levels of resistance conferred were kdr‐his < kdr < super‐kdr. However, there was significant variation in this pattern, especially for super‐kdr, for which both high and low resistance ratios were observed for several pyrethroids. We also examined the levels of resistance in heterozygotes. Resistance in each of the hybrids was generally inherited as an incompletely recessive trait, except for the kdr‐his/kdr hybrids, which showed incompletely to completely dominant resistance (ie had resistance levels comparable to kdr homozygotes). The importance of these results to understanding the frequencies of these resistance alleles in natural populations, the evolution of insecticide resistance and resistance management strategies are discussed. 相似文献
70.