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111.
Visceral fat adiposity plays an important role in the development of metabolic syndrome. We reported previously the impact of human visceral fat adiposity on gene expression profile of peripheral blood cells. Genes related to circadian rhythm were highly associated with visceral fat area and period homolog 1 (PER1) showed the most significant negative correlation with visceral fat area. However, regulation of adipose Per1 remains poorly understood. The present study was designed to understand the regulation of Per1 in adipose tissues. Adipose Per1 mRNA levels of ob/ob mice were markedly low at 25 and 35 weeks of age. The levels of other core clock genes of white adipose tissues were also low in ob/ob mice at 25 and 35 weeks of age. Per1 mRNA was mainly expressed in the mature adipocyte fraction (MAF) and it was significantly low in MAF of ob/ob mice. To examine the possible mechanisms, 3T3-L1 adipocytes were treated with H2O2, tumor necrosis factor-α (TNF-α), S100A8, and lipopolysaccharide (LPS). However, no significant changes in Per1 mRNA level were observed by these agents. Exposure of cultured 3T3-L1 adipocytes to low temperature (33°C) decreased Per1 and catalase, and increased monocyte chemoattractant protein-1 (Mcp-1) mRNA levels. Hypothermia also worsened insulin-mediated Akt phosphorylation in 3T3-L1 adipocytes. Finally, telemetric analysis showed low temperature of adipose tissues in ob/ob mice. In obesity, adipose hypothermia seems to accelerate adipocyte dysfunction.  相似文献   
112.
Several new methylenedioxyphenyl (MDP) ethers were synthesised from sesamol and methoxy substituted sesamols and screened as pyrethrum synergists. In general, the synergistic activity increased with the methoxyl substituents and decreased in the corresponding alkenyl analogs. The synergistic activity of alkyl ethers was found to vary with the alkyl chain, n-propyl ethers showing the maximum. In the case of alkenyl ethers, the activity followed the order γ,γ-dimethyl allyl>β-methallyl > allyl and showed no correlation between Rm and synergistic activity.  相似文献   
113.
We report an adolescent patient with Prader-Willi syndrome accompanying suppressible hypergonadotropism. The subject is an 18-year-old female. She was obese (body mass index: 35.7) and hypomyotonic with mental retardation. On endocrinological examination, a high serum LH concentration and hyperresponsiveness of luteinizing hormone (LH) to intravenously administered LH-Releasing Hormone (LH-RH) were observed, while the basal follicle stimulating hormone level was within the normal range. In addition, serum dehydroxyepiandrosterone sulfate (DHEA-S) was also increased. Following 2 mg dexamethasone administration for 7 days, serum LH and DHEA-S were almost normalized and hyperresponse of LH to LH-RH completely disappeared. The present study provides evidence that altered responsiveness to adrenal steroid may be involved in the establishment of hypergonadotropinism in an adolescent patient with Prader-Willi syndrome.  相似文献   
114.
Albumin preparations from four kinds of wheat flour (Durum, Manitoba No. 2, Western White and Norin No. 26) were analyzed by Immunoelectrophoresis. Seven to eleven components were detected for each preparation. They were classified and designated on the basis of the electrophoretic mobility (R) and the character of precipitin lines formed by antigen-antibody reactions.  相似文献   
115.
116.
The literature concerning the tissue culture of Taxus sp. as an alternative source for taxoid production is reviewed. The aim of this review is to summarize and discuss the progress achieved with the approaches and methods used for the establishment of various Taxus culture systems, the methods used for the evaluation of taxoid production, the multiple factors which control taxoid production and the feasibility of the in vitro production of taxoids on a commercial scale.  相似文献   
117.
To investigate soluble IL-2 receptor (sIL-2R) levels in nasal allergy, the sera and nasal secretions from patients with nasal allergy and from healthy subjects were subjected to a double-epitope enzyme-linked immunosorbent assay. Significant elevation of sIL-2R concentrations in the sera and nasal secretions was observed in the allergy patients (n = 26) compared with those of healthy subjects (n = 9). IL-2R-positive (CD25(+)) cells were observed in the crust formed in an allergic nasal mucosa. The concentration of sIL-2R in the sera correlated neither with the eosinophil count of the peripheral blood count nor with clinical severity. The concentration of sIL-2R in the nasal secretions was significantly higher compared with that in the sera from allergic patients (p < 0.01), whereas no significant difference was observed between sIL-2R levels in the sera and nasal sections from normal subjects. These findings indicate that sIL-2R plays an essential role in allergic processes by regulating IL-2R-positive cells recruited into the nasal mucosa.  相似文献   
118.
The seeds of a Japanese terrestrial orchid (Bletilla striata Rchb.f.) were germinated and cultured on solidified new Dogashima (ND) medium for 10 days. These embryos were then precultured on ND medium supplemented with 0.3 m sucrose for 3 days at 25°C in continuous dark. The embryos were then overlaid with a mixture of 2 m glycerol and 0.4 m sucrose for 15 min at 25°C and finally dehydrated with highly concentrated vitrification solution (PVS2) for 3 h at 0°C prior to immersion into liquid nitrogen for 30 min. After rapid warming, the embryos were washed with liquid ND medium supplemented with 1.2 m sucrose for 20 min and then plated on ND medium. Successfully vitrified and warmed embryos developed into normal plantlets. The rate of plant regeneration amounted to about 60%. This vitrification method appears to be a promising technique for cryopreservation of orchids. Received: 19 September 1996 / Revision received: 3 January 1997 / Accepted: 24 February 1997  相似文献   
119.
We examined the nuclear lamina in the quickly frozen anterior pituitary cells by electron microscopic techniques combined with freeze substitution, deep etching, and immunocytochemistry and compared it with that in the chemically fixed cells. By quick-freeze freeze-substitution electron microscopy, an electron-lucent layer, as thick as 20 nm, was revealed just inside the inner nuclear membrane, whereas in the conventionally glutaraldehyde-fixed cells the layer was not seen. By quick-freeze deep-etch electron microscopy, we could not distinguish definitively the layer corresponding to the nuclear lamina in either fresh unfixed or glutaraldehyde-fixed cells. Immunofluorescence microscopy showed that lamin A/C in the nucleus was detected in the acetone-fixed cells and briefly in paraformaldehyde-fixed cells but not in the cells with prolonged paraformaldehyde fixation. Nuclear localization of lamin A/C was revealed by immunogold electron microscopy also in the quickly frozen and freeze-substituted cells, but not in the paraformaldehyde-fixed cells. Lamin A/C was localized mainly in the peripheral nucleoplasm within 60 nm from the inner nuclear membrane, which corresponded to the nuclear lamina. These results suggest that the nuclear lamina can be preserved both ultrastructurally and immunocytochemically by quick-freezing fixation, rather than by conventional chemical fixation.  相似文献   
120.
Fucosylation is an important type of glycosylation involved in cancer, and fucosylated proteins could be employed as cancer biomarkers. Previously, we reported that fucosylated N-glycans on haptoglobin in the sera of patients with pancreatic cancer were increased by lectin-ELISA and mass spectrometry analyses. However, an increase in fucosylated haptoglobin has been reported in various types of cancer. To ascertain if characteristic fucosylation is observed in each cancer type, we undertook site-specific analyses of N-glycans on haptoglobin in the sera of patients with five types of operable gastroenterological cancer (esophageal, gastric, colon, gallbladder, pancreatic), a non-gastroenterological cancer (prostate cancer) and normal controls using ODS column LC-ESI MS. Haptoglobin has four potential glycosylation sites (Asn184, Asn207, Asn211, Asn241). In all cancer samples, monofucosylated N-glycans were significantly increased at all glycosylation sites. Moreover, difucosylated N-glycans were detected at Asn 184, Asn207 and Asn241 only in cancer samples. Remarkable differences in N-glycan structure among cancer types were not observed. We next analyzed N-glycan alditols released from haptoglobin using graphitized carbon column LC-ESI MS to identify the linkage of fucosylation. Lewis-type and core-type fucosylated N-glycans were increased in gastroenterological cancer samples, but only core-type fucosylated N-glycan was relatively increased in prostate cancer samples. In metastatic prostate cancer, Lewis-type fucosylated N-glycan was also increased. These data suggest that the original tissue/cell producing fucosylated haptoglobin is different in each cancer type and linkage of fucosylation might be a clue of primary lesion, thereby enabling a differential diagnosis between gastroenterological cancers and non-gastroenterological cancers.  相似文献   
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