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31.
The effect of Jeo Dang-Tang on cytokines production in the patients with cerebral infarction 总被引:2,自引:0,他引:2
Jeong HJ Kang SY Kim SY Lee SG Lee SG Sung KK Kim HM 《Immunopharmacology and immunotoxicology》2003,25(4):503-512
The herbal formulation "Jeo Dang-Tang" (JDT) has long been used for various cerebrovascular diseases. However, very little has scientific investigation been carried out. The aim of the present study is to investigate the effect of JDT on the production of various cytokines in the patients with cerebral infarction (CI). Peripheral blood mononuclear cells (PBMC) obtained from the patients with CI were cultured for 24h in the presence or absence of lipopolysaccharide (LPS) or phytohemagglutinin (PHA). The amount of interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-1beta, in culture supernatant, was significantly increased in the JDT, LPS or PHA treated cells compared to unstimulated cells (P < 0.05). We also show that increased IL-4, and IL-10 level by LPS or PHA was significantly inhibited by JDT in a dose-dependent manner. Maximal inhibition rate of IL-4 and IL-10 production by JDT was 45 +/- 2% and 51 +/- 5% for LPS-stimulated cell and 41.5 +/- 3% and 70.8 +/- 2% for PHA-stimulated cells, respectively (P < 0.05). On the other hand, JDT significantly increased the LPS or PHA-induced TGF-beta1 production (P < 0.05). These data suggest that JDT has a regulatory effect on the cytokines production, which might explain its beneficial effect in the treatment of CI. 相似文献
32.
Park HD Lee WK Ooya T Park KD Kim YH Yui N 《Journal of biomedical materials research. Part A》2003,66(3):596-604
Sulfonated polyrotaxanes (PRx-SO(3)'s), in which sulfonated alpha-cyclodextrins (alpha-CDs) were threaded onto the poly(ethylene glycol) (PEG) segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) capped with benzyloxycarbonyl (Z)-L-phenylalanine (Z-L-Phe), were prepared as a novel surface-modifying biomaterial. Surface modification of the polyurethane (PU) was carried out by blending the PRx-SO(3)'s with a PU solution, followed by solution casting. The incorporated PRx-SO(3)'s led to the enhanced hydrophilicity by changing the surface properties of the PU matrix. Modified PUs showed the stable entrapment of the PRx-SO(3)'s with little extraction into water and enhanced mechanical properties after exposure to water compared to the PU control. The incorporated PRx-SO(3)'s repelled the proteins and kept them from closely approaching the surface areas, prevented platelet activation by thrombin, and effectively repelled bacteria. These results suggest that both the supramolecular structure of the polyrotaxanes and exposure of the sulfonated groups onto the surfaces contribute to these phenomena. Thus, surface modification with PRx-SO(3)'s is suggested to be useful for the fabrication of biocompatible medical devices. 相似文献
33.
J. Chuang M. -T. Lin S. -A. Chan S. -J. Won 《Pflügers Archiv : European journal of physiology》1990,415(5):606-610
The changes in thermoregulatory effectors produced by an injection of polyriboinosinic acid: polyribocytidylic acid (Poly
I:C) or interferon were assessed and compared in control rats, in rats with hypothalamic somatostatin (SS) receptor blockade
and in rats with hypothalamic SS depletion. Intrahypothalamic (i.h., 0.05–0.50 μg) or intraperitoneal (i.p., 100–600 μg) administration
of Poly I:C caused a dose-related rise in colon temperature in control rats at all ambient temperatures (Ta) studied. A Poly I:C-induced fever was produced by increased metabolism at a Ta of 8 °C, whereas at 30 °C, it was caused by cutaneous vasoconstriction. At a Ta of 22 °C, the fever was caused by increased metabolism and cutaneous vasoconstriction. On the other hand, i.h. administration
of SS-14 antagonist (0.1–0.5 ng) caused a dose-related fall in colon temperature at Ta of 8 °C or 22 °C. At a Ta of 8 °C, the hypothermia was caused by decreased metabolism, whereas at 22 °C, it was caused by decreased metabolism and
cutaneous vasodilation. At a Ta of 30 °C, the thermoregulatory effectors were not affected by SS-14 antagonist treatment. Furthermore, the fever induced
by Poly I:C or interferon was significantly reduced by pretreatment of rats with an i.p. dose of cysteamine (30 mg. kg−1) or an i.h. dose of SS-14 antagonist (0.1 ng). The results indicate that a somatostatinergic pathway in rat hypothalamus
may mediate the fever induced by interferon or its inducer Poly I:C. 相似文献
34.
Contrast enhancement during the dynamic MR imaging is important for the detection and characterization of focal liver lesions. The purpose of this study was to determine whether or not a timing examination with a injection of a 1.0-mL bolus of gadopentetate dimeglumine into the antecubital vein followed by rapid dynamic scanning and measurement of signal intensity of the aorta could help to obtain proper arterial-dominant phase images for the characterization of focal hepatic lesions during subsequent multiphase dynamic MR imaging. The imaging delay to acquisition of the first gadolinium-enhanced image for multiphase dynamic MR imaging was set to equal the time to peak aortic enhancement during the test examination. The first contrast-enhanced images of 80 patients with 160 focal liver lesions (hepatocellular carcinoma, n = 79; cavernous hemangioma, n = 51; metastatic tumor, n = 30) were then retrospectively reviewed. Peak aortic enhancement occurred between 10 and 28 seconds (mean, 16.5 seconds +/- 3.1) after starting the infusion of contrast material in 80 patients during the test-examination. Depending on the findings of intrahepatic vascular enhancement on the full-scale dynamic images, hepatic arterial phase (n = 11, 14%) or sinusoid phase (n = 65, 81%) imaging was obtained during the first gadolinium-enhanced acquisition in 76 (95%) of 80 patients. Three different lesions were well characterized and easily distinguished from each other (p < .0001) on the first-phase images depending on their enhancement pattern. In the majority of patients, timing examination with test-bolus injection was helpful in obtaining qualified images for the characterization of various focal lesions. 相似文献
35.
Park SK An SJ Hwang IK Kim DW Jung JY Won MH Choi SY Kwon OS Jeong YG Kang TC 《Neuroscience research》2004,49(4):405-416
The present study was performed to determine whether the effects induced by GABA(B) receptor-acting drugs would be related with the alteration in GABA(B) receptor expression in the hippocampus using Mongolian gerbil, a genetic epilepsy model. The distribution patterns of both GABA(B) receptor 1A/B and GABA(B)receptor 2 immunoreactivities were similarly detected in the hippocampi of normal and seizure-prone gerbils. Following baclofen (GABA(B) receptor agonist) or phaclofen (GABA(B) receptor antagonist) treatment, GABA(B) receptor immunoreactivities were decreased or increased by dose-dependent manners, respectively. Vigabatrin (GABA transaminase inhibitor) or 3-mercaptopropionic acid (GAD inhibitor) treatment did not affect GABA(B) receptor expressions. These findings suggest that GABA(B) receptor expression in the gerbil hippocampus may be altered by baclofen or phaclofen treatment. 相似文献
36.
Moo -Yeol Lee Hyo -Weon Bang In -Ja Lim Dae -Yong Uhm Sang -Don Rhee 《Pflügers Archiv : European journal of physiology》1994,429(1):150-152
Large conductance Ca2+-activated K+ channel was identified and studied in excised inside-out membrane patches of freshly dispersed smooth muscle cells from rabbit
gastric antrum. The current-voltage relationship of the single channel was linear from -80 to +80 mV of pipette voltage in
which single channel conductance was 249±17.8 pS (n=19) in symmetrical concentration of K+ (145mM) across the patch. Activity of the channel (NPo) depended not only on cytoplasmic calcium concentration but also on
membrane potential. MgATP increased NPo in a dose-dependent manner and Mg2+ was prerequisite for the effect. Okadaic acid (l00nM), inhibitor of protein phosphatases, increased NPo further in the presence
of MgATP. Therefore, it would be concluded that activity of the calcium-activated K+ channel in gastric smooth muscle cells was controlled by phosphorylation state of the channel protein and the state is further
modulated by membrane-delimited protein kinase and protein phosphatase activities. 相似文献
37.
Yong D Lim JG Choi JR Park Q Yang CH Choi SH Jeong HJ Song KS 《Yonsei medical journal》2000,41(1):136-139
Klinefelter syndrome (KS) is often associated with various neoplasms, especially germ cell tumors. Mediastinum is the most favored site of extragonadal germ cell tumors with KS, which is somewhat different from those without KS. The retroperitoneal germ cell tumor in KS is very rare. A five-month-old boy with an abdominal mass was found to have a retroperitoneal tumor. After surgical removal, he was diagnosed to have mature cystic teratoma. Cytogenetic study of his peripheral lymphocytes revealed that his karyotype was consistent with KS. This case suggests that patients with KS might be at risk of having germ cell tumors in sites other than mediastinum. It also suggests that all cases with these tumors should be screened for the presence of karyotypic abnormalities, and it might help to assess the exact correlation between germ cell tumors and KS, and to treat them accordingly. 相似文献
38.
4-1BB(CD137) is a member of the tumour necrosis factor receptor superfamily and is expressed on activated T cells, monocytes and natural killer (NK) cells. The interaction of 4-1BB and 4-1BB ligand provides a costimulatory signal leading to T-cell activation. The expression of 4-1BB has been known to be activation dependent. Interestingly, we found that expression of 4-1BB increased in human peripheral blood mononuclear cells after exposure to mitomycin C. Thus, we tested whether the treatment with other DNA-damaging agents, such as doxorubicin, bleomycin, and gamma-irradiation, could induce 4-1BB expression. The data indicated that 4-1BB expression increased dose-dependently by these agents reaching maximum at 2-3 days after the exposure. We found that the major 4-1BB-expressing population was CD3+ T cells, although a moderate number of CD14+ cells and a few NKB1+ cells also expressed 4-1BB. The levels of 4-1BB expression induced by anticancer drugs, were relatively lower than that induced by CD3 ligation. Interestingly, at subcytotoxic concentrations, doxorubicin and bleomycin considerably enhanced 4-1BB expression induced by CD3 ligation in CEM cells. The ligation of the damage-induced 4-1BB by monoclonal antibody enhanced the viability and proliferating capacity of the cells. In conclusion, the expression of 4-1BB might be one of the cellular responses of the immune cells against various genotoxic stresses. 相似文献
39.
40.
In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis. 相似文献