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81.
82.
Savinin, a lignan from Pterocarpus santalinus inhibits tumor necrosis factor-alpha production and T cell proliferation 总被引:1,自引:0,他引:1
Cho JY Park J Kim PS Yoo ES Baik KU Park MH 《Biological & pharmaceutical bulletin》2001,24(2):167-171
Two lignans were isolated from the heartwood of Pterocarpus santalinus by activity-guided fractionation and investigated for their biological properties and molecular mechanism of action. On the basis of their spectroscopic data, these compounds were identified as savinin (1) and calocedrin (2), dibenzyl butyrolactone-type lignan compounds having an alpha-arylidene gamma-lactone structure. These lignans significantly inhibited tumor necrosis factor (TNF)-a production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and T cell proliferation elicited by concanavalin (Con A), without displaying cytotoxicity. The molecular inhibitory mechanism of compound 1 was confirmed to be mediated by the non-polar butyrolactone ring, according to a structure-relationship study with structurally related and unrelated compounds, such as arctigenin (a dibenzyl butyrolactone type lignan), eudesmin (a furofuran type lignan), isolariciresinol (a dibenzylbutane type lignan), and cynaropicrin (a sesquiterpene lactone). The results suggest that savinin may act as an active principle in the reported biological activities of P. santalinus, such as antiinflammatory effect, by mediation of the butyrolactone ring as a valuable pharmacophore. 相似文献
83.
Nothing is directly known about the bioavailability of vitamin B-12 from dairy products or fortified grain products. We directly studied vitamin B-12 absorption from water, milk and fortified bread in adult subjects using (58)Co-labeled vitamin B-12 and a whole body gamma-ray counter/spectrophotometer. Sixteen healthy men and women over the age of 60 y with normal serum levels of vitamin B-12 and normal basal gastric acid secretion were studied. (58)Co vitamin B-12 (0.25 microg) was administered in water, milk or fortified bread to each subject along with 185 kBq (5.0 microCi) (51)Cr as a stool marker. Whole body counting was performed 30 min after ingestion of the radioactive dose and at 7 and 14 d after dosing. Mean absorptions from water, milk and fortified bread were 55, 65 and 55%, respectively, and did not differ. The high body retention of the extrinsic vitamin B-12 label from milk and bread may warrant a greater use of such fortified products in the elderly to ensure vitamin B-12 adequacy. 相似文献
84.
Shin DH Lee HY Lee KH Kim HJ Lee WJ Hwang DH Baik SH Cho SS 《Neuroscience letters》2000,278(1-2):73-76
In this study, we demonstrated bcl-2 expression in the rabbit brain using in situ hybridization and compared the results with the studies done on the other animals. Although the bcl-2 expressions of the rabbit were generally similar to those of the other animals, some differences were also found; the cells in molecular and Purkinje cell layers of the cerebellum, which were bcl-2 negative in the others, showed intense bcl-2 positive signals, while the ependymal cells, arachnoid villi and granular layer, which were positive in the other animals, were not well stained with bcl-2 riboprobes in the rabbit brain. Our findings clearly showed the similarities and differences of rabbit bcl-2 mRNA as compared with the other species for the first time, and provided the basis of further study on the properties of bcl-2 in this species. 相似文献
85.
In order to study the relationship between the serum ferritin level and the components of the insulin resistance syndrome in type 2 diabetic patients, we evaluated fifty type 2 diabetic patients who were selected according to NDDG/WHO criteria from those patients attending Korea University Hospital from 1997 to 1998. Twenty-five healthy non-diabetic subjects of comparable age and sex distribution acted as a control group. The results showed that the value of log ferritin was higher in the type 2 diabetes patients than the control subjects, but not at a statistically significant level (p = 0.09). Log ferritin was correlated with fasting blood sugar level (r = 0.235, p = 0.048) and body mass index (BMI) (r = 0.285, p = 0.05). In the type 2 diabetic patients, log ferritin was correlated with fasting C-peptide (r = 0.478, p = 0.009). In the control subjects, log ferritin was correlated only with BMI (r = 0.477, p = 0.012). In a stepwise multiple regression analysis, the diabetic group showed a significant correlation between fasting C-peptide and log ferritin (p = 0.001). In the control group, the fasting sugar level was significantly correlated with log ferritin (p = 0.034). These results suggest that serum ferritin can be employed as a marker of not only glucose homeostasis but also insulin resistance both in type 2 diabetic and control subjects. 相似文献
86.
Jung Ah Min Shin Taek Oh Jung Eun Kim Baik Kee Cho Nak Gyun Chung Hyun Jeong Park 《ANNALS OF DERMATOLOGY》2010,22(4):447-451
Lymphomatoid papulosis (LyP) is a benign, self-healing, papular eruption that can wax and wane over time. Transformation to T-cell lymphoma has been well documented in 10% to 20% of adults with LyP. However, this transformation rarely occurs in patients younger than 20 years of age. Here, we present the first known pediatric patient in Korea, a 12-year-old boy who developed a subcutaneous nodule on the scrotum 13 months after papulonecrotic lesions of LyP were identified on both lower extremities and face. Histological and immunohistochemical examination of the subcutaneous nodule revealed anaplastic large cell lymphoma (ALCL). A T-cell receptor gene rearrangement analysis demonstrated an identical rearranged pattern in the two specimens, indicating that a common T-cell clone had proliferated over time in both the LyP and ALCL lesions. 相似文献
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89.
Si Eun Hwang Baik Hwan Cho Ichiro Hirai Hyoung Tae Kim Ji‐Hyun Kim Mineko Fujimiya Gen Murakami Wataru Kimura 《Clinical anatomy (New York, N.Y.)》2010,23(6):712-719
At 8–16 weeks of gestation, Spiegel's lobe of the caudate lobe appears as a sac‐like herniation of the liver parenchyma between the inferior vena cava and ductus venosus or Arantius' duct. In 5 of 11 fetuses at 20–30 weeks of gestation, we found that an external notch was formed into the posterior aspect of the caudate lobe by a peritoneal fold containing the left gastric artery. This notch appeared to correspond to that observed in adults, which is usually seen at the antero‐inferior margin of the lobe after rotation of the lobe along the horizontal or transverse axis. However, the notch did not accompany two of the three fetuses in which the left hepatic artery originated from the left gastric artery. Notably, until 9–10 weeks of gestation, the inferior and left part of Spiegel's lobe rode over the hepatoduodenal ligament and protruded medially into the lesser sac (bursa omentalis) behind the stomach. Thus, the fetal Winslow's foramen was located at the “superior” side of the ligament. However, as seen in adults, the protruding Spiegel's lobe was located at the posterior side of the lesser omentum. Therefore, a hypothetical rotation along the transverse axis in the later stages of development seems necessary to explain this repositioning. Considering that Spiegel's lobe develops faster than surrounding structures, it is likely that the lesser sac resulting from the rotation of the gastrointestinal tract, which actively contributes to facilitate the growth of the Spiegel lobe. Clin. Anat. 23:712–719, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
90.
BACKGROUD/OBJECTIVESData regarding the effects of poly-γ-glutamic acid (γ-PGA) on sleep status are limited. This study aimed to test whether γ-PGA and vitamin B6 (VitB6) supplements improve sleep duration and quality.SUBJECTS/METHODSA factorial randomized, double-blinded, placebo-controlled crossover study included 47 adults (25 men and 22 women) who were free of chronic disease. Stratified randomized allocation considered age and gender for three interventions, group A (supplementation with γ-PGA 600 mg; n = 16), group B (supplementation with VitB6 100 mg; n = 14), and group C (dual supplementation of both γ-PGA 600 mg and VitB6 100 mg; n = 17). Participants underwent a 1-mon intervention period, followed by a 1-mon washout period, and then a second 1-mon intervention period. Differences (mean ± SD) in nighttime sleep status before and after supplementation were compared between the placebo and intervention groups using nonparametric tests.RESULTSSignificant changes in sleep duration (0.27 ± 0.98 h, P < 0.05) and the Pittsburgh Sleep Quality Index global score (−0.52 ± 1.58, P < 0.05) indicating improved sleep status were observed in the intervention compared with the placebo of group C while no significant changes were observed in groups A and B. No statistical significance was detected between the intervention and the placebo; however, there was a greater increase in the group C intervention (4.59 ± 38.5 ng/mL) in serum serotonin concentrations than the groups A and B interventions. No side effects were observed.CONCLUSIONSOn the basis of these findings, the dual supplementation of γ-PGA and VitB6 may be effective as functional food components to improve nighttime sleep status.Trial RegistrationClinical Research Information Service Identifier: KCT0005083 相似文献