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991.
Influence of a human protease inhibitor on surgical stress induced immunosuppression 总被引:21,自引:0,他引:21
Sato N Endo S Kimura Y Ikeda K Aoki K Iwaya T Akiyama Y Noda Y Saito K 《Digestive surgery》2002,19(4):300-305
BACKGROUND/AIM: Postoperative tissue injury and immunosuppression can occur after major surgery. In this study, we explore the potential benefits of administering a protease inhibitor to treat immunosuppression caused by surgical stress. METHODS: Sixteen patients with esophageal cancer were preoperatively allocated at random into two equal groups. A urinary trypsin inhibitor, ulinastatin (UTI), was intravenously administered to the treatment (UTI) group at a dose of 150,000 U every 12 h from the start of surgery until postoperative day 5, whereas the control group received a placebo. One unit of UTI was defined as the amount of UTI necessary to inhibit the activity of 2 microg of bovine pancreatic trypsin by 50%. We measured the plasma levels of polymorphonuclear neutrophil elastase, interleukin 8, circulating T lymphocyte subsets, and mitogenic activity and in vitro production of tumor necrosis factor alpha in lipopolysaccharide-stimulated whole blood. RESULTS: The postoperative serum value of polymorphonuclear neutrophil elastase was significantly lower in the UTI group, but the interleukin 8 concentrations did not significantly vary between the two groups. On the other hand, the severity of the postoperative immunosuppression was reduced in the UTI group, and immune functions, such as the numbers of T lymphocytes, the mitogenic activity of lymphocytes, and the level of tumor necrosis factor alpha production in whole blood, recovered significantly earlier in the UTI group. CONCLUSION: These data suggest that a protease-modulating therapy may be a new strategy for the treatment of surgical stress induced immune dysfunction. 相似文献
992.
Carp oil or oleic acid,but not linoleic acid or linolenic acid,inhibits tumor growth and metastasis in Lewis lung carcinoma-bearing mice 总被引:5,自引:0,他引:5
Kimura Y 《The Journal of nutrition》2002,132(7):2069-2075
I examined the effects of carp oil, oleic acid, linoleic acid and linolenic acid on tumor growth and metastasis to the liver in mice implanted intrasplenically with highly metastatic Lewis lung carcinoma (LLC) tumors. Carp oil (0.1 or 0.2 mL per mouse) significantly reduced tumor growth and metastasis to the liver. Carp oil at 100 or 1000 mg/L inhibited the DNA synthesis in LLC cells, the capillary-like tube formation of human dermal microvascular endothelial cells (HMVEC) at 1000 mg/L and the adherence of LLC cells to HMVEC at 10 to 1000 mg/L (in vitro). Carp oil (0.2 mL per mouse) inhibited the angiogenesis induced by Matrigel supplemented with vascular endothelial growth factor (VEGF) and heparin (in vivo). Antitumor and antimetastatic actions of carp oil might be partly attributable to the inhibition of DNA synthesis in LLC cells and angiogenesis through the inhibition of the adherence of LLC cells to the microvascular endothelium. Oleic acid (0.1 or 0.2 mL per mouse) significantly inhibited the metastasis to the liver, but it had no effect on the primary solid-tumor growth. Oleic acid inhibited the angiogenesis in both in vitro and in vivo models. Oleic acid at 1000 micromol/L inhibited the DNA synthesis in LLC cells but did not affect the DNA synthesis in HMVEC. These inhibitory actions of oleic acid may be attributable to the inhibition of angiogenesis induced by the tumor. Linoleic acid and linolenic acid had no effect on tumor growth or metastasis to the liver. 相似文献
993.
Butyl benzyl phthalate (BBP) and bisphenol A (BPA), termed endocrine disrupters, are known to mimic oestrogen in their actions, and therefore there is concern about their effect on reproductive functions. Since it is reported that the inhibitory action of oestrogen on the pulsatile secretion of luteinizing hormone (LH) is enhanced under insulin-induced hypoglycaemia, whether this also applies to BBP and BPA was examined in the present study. In adult ovariectomized (OVX) rats, the pulsatile LH secretion 24 h after subcutaneous injection of 10 mg BBP (BBP-treated), 10 mg BPA (BPA-treated) or 100 ng 17beta-oestradiol (E2-treated), all of which were dissolved in sesame oil, was not changed significantly compared to that after the injection of sesame oil only. Furthermore, in oil-treated OVX rats, the pulsatile LH secretion immediately after intravenous injection of insulin (1.0 U) was not changed compared to that after saline injection. In BBP-treated OVX rats, the injection of insulin (1.0 U) significantly decreased the number of LH pulses as in E2-treated OVX rats. The injection of insulin did not significantly affect the amplitude of LH pulses in BBP-, BPA- and E2-treated OVX rats. The results indicate that the oestrogenic action of BBP is significantly enhanced by insulin-induced hypoglycaemia and thus the pulsatile LH secretion is inhibited. We suggest that weak oestrogenic endocrine disrupters may become harmful to reproductive functions even in adult female rats, if acting under a low energy state. 相似文献
994.
Expression of protein kinase C in song control nuclei of deafened adult male Bengalese finches 总被引:1,自引:0,他引:1
Auditory feedback is necessary to maintain singing in the adult male Bengalese finch (songbirds/oscines). Their song patterns are altered within a month following cochlear removal-induced deafness. Stabilization of song patterns occurs thereafter. To clarify what kind of changes appear in the brain of deafened birds, we examined immunohistochemically the expression of protein kinase C (PKC), considered a molecular marker for synaptic plasticity, in the robust nucleus of the archistriatum (RA), one of the song control nuclei in the forebrain of finches. Two weeks after cochlear removal, immunoreactive fibers and terminals in the RA transiently increased, and thereafter tended to decrease gradually. Moreover, the degree of song alteration and stability paralleled these changes in the RA. The immunoreactivity of the RA remained unchanged in intact birds.These results indicate that surgical deafening increases the expression of PKC in the RA. These changes in the RA are related to the alteration of song patterns in the deafened adult Bengalese finch. 相似文献
995.
We previously cloned a voltage-dependent Ca2+ channel alpha1 subunit LoCa(v)2 cDNA from the squid optic lobe. LoCa(v)2 is designated as a non-L-type voltage-dependent Ca2+ channel based on its amino acid sequence. We performed functional expression experiments of LoCa(v)2 in oocytes and characterized the expressed currents electrophysiologically and pharmacologically. The LoCa(v)2 current was high voltage-activated and the peak current was maximal at +20 mV and lasted for long during activation. The LoCa(v)2 current was not inhibited by the drugs and toxins examined except for omega-agatoxin IVA and PLTX-II. Omega-agatoxin IVA, which is a P-type channel blocker, moderately inhibited the LoCa(v)2 current at higher concentration. PLTX-II, which blocks insect presynaptic Ca2+ channel, inhibited the LoCa(v)2 current at lower concentration. Immunohistochemical investigation showed that the LoCa(v)2 protein may exist at presynaptic terminals in the squid optic lobe. These results suggest that LoCa(v)2 is an omega-agatoxin IVA and PLTX-II-sensitive presynaptic Ca2+ channel in the squid nervous system. 相似文献
996.
OBJECT: The naphthylsulfonate derivative suramin is an inhibitor of growth factor receptors (receptor tyrosine kinases) and G protein-coupled P2Y receptors. Both types of these receptors are suspected of being involved in cerebral vasospasm after subarachnoid hemorrhage (SAH). In the current study, the authors examined the therapeutic effects of suramin and a selective P2X-receptor antagonist, pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS), in the reversal of vasospasm in an established canine double-hemorrhage model. METHODS: Twenty-four dogs underwent double blood injection into the cisterna magna, with injections given on Days 0 and 2. The dogs were divided randomly into three groups (six animals in each group) to be treated from Days 2 through 6 with the vehicle dimethyl sulfoxide, suramin, or PPADS. An additional group of six dogs received double blood injection without any treatment and served as an SAH control group. The animals were killed on Day 7. Angiography was performed on Day 0 before blood injection and again on Day 7 before the animals were killed. After the death of the animals, the basilar arteries (BAs) were collected for morphological studies and determination of tyrosine kinase expression, and the bloody cerebrospinal fluid (CSF) produced by the hemorrhages was collected for measurement of oxyhemoglobin and adenosine triphosphate (ATP). In the SAH control group, the mean diameter of the BAs on Day 7 was 46.23 +/- 6.32% of the value on Day 0 (which served as a reference of 100%). In the DMSO-treated group, the mean residual diameter of the BA was 47.77 +/- 0.8% on Day 7 compared with the value on Day 0. Suramin, but not PPADS, increased the residual diameter to 74.02 +/- 4.24% on Day 7. On Day 7 the level of ATP in the CSF was decreased and the level of oxyhemoglobin was increased, compared with values measured on Day 0. Suramin, but not PPADS, reduced tyrosine phosphorylation in the spastic BAs. CONCLUSIONS: By reducing tyrosine kinase activity, suramin may be useful in the treatment of cerebral vasospasm. 相似文献
997.
Background/Purpose: To evaluate if thrombocytopenia may be related to plasma thrombopoietin level (P-TPO) in postoperative biliary atresia (BA). Methods: Forty-three postoperative BA patients aged 1 to 20 years were included. P-TPO was measured by enzyme immunoassay. P-TPO was compared with platelet counts (Plt), Child's classification, presence of splenomegaly, and liver function tests. Results: P-TPO significantly correlated with Plt, child's classification, serum albumin, and cholinesterase level, respectively. In 4 patients undergoing portal decompression procedure, preoperative and postoperative Plt and P-TPO were 87.5 [plusmn] 69.1 [times ] 103 and 50.3 [plusmn] 28.0, 118.8 [plusmn] 62.3 [times ] 103/mm3, and 53.0 [plusmn] 55.0 pg/mL, respectively, without significant difference. In 6 patients undergoing liver transplantation (LTx), Plt and P-TPO after LTx was 157.5 [plusmn] 83.5 [times ] 103 and 143.5 [plusmn] 75.2, respectively, which were significantly higher than those before LTx (55.0 [plusmn] 15.6 [times ] 103/mm3 and 53.2 [plusmn] 32.9 pg/mL). Conclusion: Thrombocytopenia in postoperative BA may be caused by decreased plasma TPO level in accordance with the severity of liver dysfunction rather than hypersplenism. J Pediatr Surg 37:1195-1199. 相似文献
998.
Expression of CD44v6 in advanced gastric cancer and its relationship to hematogenous metastasis and long-term prognosis 总被引:30,自引:0,他引:30
Yamaguchi A Goi T Yu J Hirono Y Ishida M Iida A Kimura T Takeuchi K Katayama K Hirose K 《Journal of surgical oncology》2002,79(4):230-235
BACKGROUND AND OBJECTIVES: Variants of CD44 have been proposed to be important in promoting tumor progression and metastasis. We attempted to determine the expression of CD44v6 product in advanced gastric cancer and to evaluate its prognostic value. METHODS: The expression of CD44v6 was analyzed immunohistochemically in advanced gastric cancers using monoclonal antibody, 44-2V. We investigated the relationship between CD44v6 expression and prognosis in 201 gastric cancer patients. RESULTS: Ninety-five (47.3%) of 201 cancer tissues expressed CD44v6. The expression of CD44v6 protein was significantly higher in differentiated, adenocarcinoma than in diffuse type carcinoma. The CD44v6-positive cancers were more frequently associated with hematogenous metastasis. There was no significant correlation between CD44v6 immunoreactivity, and prognosis among the combined cases. Among patients with differentiated adenocarcinoma, however, the prognosis was significantly poorer in patients with CD44v6-positive tumors than in those with CD44v6-negative tumors. CONCLUSIONS: CD44v6 protein may have an important role in hematogenous metastasis, and may be a biologic marker of prognostic significance in differentiated type gastric cancers. 相似文献
999.
Growth Control of C6 glioma in vivo by Nerve Growth Factor 总被引:7,自引:0,他引:7
Treatment with nerve growth factor (NGF) causes differentiation of rat C6 glioma cells and strongly inhibits their proliferation in vitro. This suggests that induction of NGF-mediated differentiation may provide a novel therapeutic approach to growth control of glial tumors. We examined the effects of NGF treatment on the growth potential of C6 glioma, which expressed NGF receptor in vivo. C6 glioma cells (1 × 106 cells/10 l) were transplanted into the rat striatum. After 4 days, the animals were given successive injections of 100 ng NGF into the growing tumor at every 4 days (n = 10 rats). Controls were subjected to identical procedures with vehicle which did not contain NGF (n = 10 rats). At 14 days after transplantation, we evaluated the tumor volume, proliferative cell index (PCI) based on the MIB-1 immunoreactivity and enzyme activities related to energy metabolism by enzyme histochemistry. We found that the NGF treatment markedly reduced the tumor volume of the C6 glioma (34.00 ± 8.47 mm3 to 7.22 ± 4.92 mm3, p < 0.01). NGF treatment also decreased the PCI (33.34 ± 9.57% to 3.85 ± 3.56%, p < 0.01) with a negative correlation with tumor volume (r = 0.972, p < 0.01), and the hexokinase (HK) and glucose-6-phosphate dehydrogenase (G6PDH) activities (p < 0.01 and p < 0.01, respectively) which reflect the demand for nucleic acid synthesis for proliferation through the glycolytic and pentose phosphate pathways. The present results demonstrate for the first time that inhibition of tumor cell proliferation of C6 glioma by NGF occurs in vivo, probably through the NGF-mediated differentiation of C6 glioma cells which has been observed in in vitro studies. 相似文献
1000.
Makoto Osanai Hideki Chiba Takashi Kojima Masato Fujibe Kazuhide Kuwahara Hiromichi Kimura Masaaki Satoh Norimasa Sawada 《Japanese journal of cancer research》2002,93(5):532-541
Endothelial Fas ligand (FasL) contributes to the "immune privilege" of tissues such as testis and eye, in which apoptosis is induced in infiltrating Fas-positive activated T cells and results in the inhibition of leukocyte extravasation. In this study, we examined the role of endothelial FasL in controlling cancer cell transmigration using rat lung endothelial (RLE) cell line bearing a doxycycline-inducible hepatocyte nuclear factor (HNF)-4alpha expression system. We showed that a detectable level of FasL was expressed in RLE cells and that this expression was markedly up-regulated and well correlated to the degree of HNF-4alpha expression in a time-dependent manner. When various cancer cells were overlaid on an RLE monolayer sheet, we examined the ability of endothelial FasL to induce massive apoptosis in Fas-expressing cancer cells and found a causal link to inhibition of the transmigration. Finally, we showed that FasL was expressed in capillaries of the rat brain by immunohistochemical staining, suggesting that FasL serves its functions not only in vitro, but also in vivo. These results raise the possibility that HNF-4alpha is involved in regulating cancer cell transmigration by modulating the Fas-FasL system. 相似文献