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The formalin test was used to measure the analgesia induced by restraint in male and female rats. Animals were restrained for 30 min or left undisturbed in their cage and then (1) killed immediately to collect blood for hormonal determinations; or (2) subcutaneously injected with formalin in the hind paw (or sham-injected), introduced to an open field for recording of behaviour, and killed at the end of this procedure. In both experiments, corticosterone was found to be higher in females. In Experiment 1, the ability of restraint to be stressful was confirmed by the increase in corticosterone in both sexes and by the decrease of testosterone in males. In Experiment 2, restraint-treatment induced a reduction in licking and flexing that was limited to the second phase. The reduction occurred in different periods and to a different degree in the two sexes; it was greater in females. Spontaneous behaviours showed sex differences in restraint-treated but not in formalin-treated animals. The results show that the hormonal effects observed after restraint are not present after the formalin test and that the marked analgesia observed with phasic painful stimuli does not occur with a longer-lasting one such as that induced by formalin, after which only partial and short-lasting effects were observed.  相似文献   

3.
A histiocytic sarcoma was present at birth in a pig. On the basis of ultra-structure and structural-protein composition (presence of alpha-smooth-muscle actin but not keratin), the sarcoma component was identified as a leiomyofibrosarcoma. Lipid-laden macrophages (histiocytes), which permeated the tumour in an apparently random fashion, were somewhat atypical in that they were negative for some macrophage markers; they gave a reaction, however, for CDw14. Despite its aggressive metastatic capacity, this tumour occurred almost exclusively in the subcutis, dermis and skeletal muscle. The tumour was extensively vascularized with many small capillaries which did not express E-selectin (CD69E), MHC class II or the L-selectin (CD69L) ligand, markers characteristic of inflamed (activated) endothelial cells in pig skin. Significant numbers of the histiocytes were positive for the integrins CD18 and VLA-4 (CD49d), indicating involvement of integrin pathways in the spread or growth, or both, of the leiomyofibrosarcoma. Most of the fibrous sarcoma cells also had extensive reactivity with an antibody to the standard variant form of CD44 (CD44s).  相似文献   

4.
Cultures of endothelial (En) cells derived from human brain microvessels were established in order to characterize adhesion molecule expression and to assay the adhesion properties of neoplastic cell lines to monolayers of En cells. Low constitutive expression of beta1 integrin (CD29), and ICAM-2 (CD102) was detected on human brain microvessel En cells. The beta1 chain of the VLA integrin family, ICAM-1, E-selectin (CD62E) and VCAM-1 (CD106) but not ICAM-2 and PECAM-1 (CD31) expression was upregulated by IL1-alpha, and TNF-alpha proinflammatory cytokines. High expression of PECAM-1 was found on non-activated human brain EN cells. In order to study the potential role of adhesion molecules in neoplastic cell adhesion two tumor cell lines were chosen. Adhesion of a cell line (DU145) derived from a cerebral metastasis of prostate carcinoma to human brain microvessel En cell monolayers was less pronounced compared to adhesion of a primary prostate carcinoma cell line (ND1). Adhesion of cerebral metastatic neoplastic cell line (DU145) was not significantly influenced by incubation of endothelial cells with different proinflammatory cytokines. The adhesion capability of primary prostate carcinoma line (NDI) was significantly upregulated by TNF-alpha proinflammatory cytokine. Furthermore, the adhesion of ND1 was partly inhibited using anti-E-selectin and VCAM-1 monoclonal antibodies. There was no significant effect of anti-adhesion antibodies on the adhesion characteristics of the cerebral metastatic (DU145) cell line. Our data demonstrate that different mechanisms are involved in the adhesion of neoplastic cells to cerebral En cells and turn our attention to the importance of adhesion molecule expression in the formation of metastases.  相似文献   

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Upregulation of adhesion proteins plays an important role in mediating inflammation. The induction of adhesive molecules has been well studied, but the reversibility of their expression has not been well characterized. A neutralizing anti-TNF monoclonal antibody (cA2) was used to study the down regulation of TNF-induced E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on cultured human umbilical vein endothelial cells (HUVECs). Addition of cA2 following TNF stimulation of HUVECs enhanced the rate of E-selectin and VCAM-1 down-regulation from the cell surface and also reduced steady state E-selectin and VCAM-1 mRNA levels. The cA2-mediated disappearance of E-selectin, but not VCAM-1 protein was microtubule and not microfilament dependent. Neutralization of TNF only slightly reduced ICAM-1 cell surface levels following initial TNF stimulation, suggesting a slower turnover of ICAM-1 compared to E-selectin and VCAM-1. Microtubule inhibition during TNF stimulation partially inhibited E-selectin, VCAM-1 and ICAM-1 mRNA upregulation. VCAM-1 and ICAM-1 cell surface expression were similarly partially inhibited, however, E-selectin levels were unaffected, presumably due to the dual, opposing effect of inhibiting protein expression and inhibiting internalization. Microfilament inhibition during protein induction specifically inhibited the maximal expression of VCAM-1 protein and mRNA, without affecting E-selectin or ICAM-1. These data support the notion that E-selectin, VCAM-1, and ICAM-1 expression are differentially regulated on HUVECs and suggest that TNF neutralizing therapies may be effective because of their ability to reduce the levels of pre-existing adhesion proteins.  相似文献   

7.
STATEMENT OF PROBLEM: There are discrepancies among researchers concerning the reliability and use of temporomandibular joint sounds. PURPOSE: This study examined the reliability of mandibular movements and sounds and determined the correlation between movements and sounds. MATERIAL AND METHODS: The mandibular movements of 35 subjects diagnosed with temporomandibular disorders were recorded with 2 CCD cameras, and sounds were recorded bilaterally with Panasonic electret condenser microphones in the ear canal. Subjects performed 3 movements, each repeated 5 times. RESULTS: Reliability of maximum movements across the 5 trials was good to excellent, with Intraclass Correlation Coefficients (ICC) between 0.76 and 0.91 for all movements except protrusion. Temporomandibular sound event counts were reliable for most movements, including vertical opening, protrusion, and right and left laterotrusion (ICCs between 0.41 and 0.81). Most subjects produced sound events either in 100% or in none of the trials. Reliability for sound events was better during protrusion (ICCs between 0.56 and 0.81) than vertical opening (ICCs 0.41 to 0.64). Subjects with sound events during vertical opening (followed by closing) were significantly more likely to have sound events during protrusion (followed immediately by vertical opening and closing) (P <.01). CONCLUSION: Temporomandibular sound events are generally reliable and warrant study regarding their use in classifying and diagnosing patients with temporomandibular disorders. Condylar translation, which occurs during both vertical opening and protrusion, appears to have a strong influence on the production of temporomandibular sound events.  相似文献   

8.
Although nitric oxide (NO) and antioxidants inhibit adhesion molecule expression, their inhibitory effects on nuclear factor kappaB (NF-kappaB) activation may differ. The NO donors, but not 8-bromo-cGMP, decreased tumor necrosis factor alpha (TNF-alpha)-induced VCAM-1, ICAM-1, and E-selectin expression by 11-70%. In contrast, NAC completely abolished VCAM-1 and E-selectin expression and decreased ICAM-1 expression by 56%. Gel shift assays demonstrate that NF-kappaB activation was inhibited by both NO and antioxidants. The activation of NF-kappaB involves the phosphorylation and degradation of its cytoplasmic inhibitor IkappaB-alpha by 26S proteasomes. The 26S proteasome inhibitor MG132 prevented the degradation of phosphorylated IkappaB-alpha. NAC inhibited IkappaB kinase (IKK) activity and prevented IkappaB-alpha phosphorylation and degradation. In contrast, NO did not inhibit IKK activity, IkappaB-alpha phosphorylation, or IkappaB-alpha degradation. However, NO, but not antioxidants, induced IkappaB-alpha promoter activity. The inhibitory effects of NO on adhesion molecule expression, therefore, differs from that of antioxidants in terms of the mechanism by which NF-kappaB is inactivated.  相似文献   

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Intravenous methylprednisolone (IVMP) may inhibit inflammatory cell recruitment to active MS lesions by effects on leukocyte or endothelial cell adhesion molecule expression. We investigated 15 MS patients in relapse receiving a 5-day course of IVMP (500 mg/day) and 15 normal subjects. Patients' blood samples were obtained pretreatment, at 6 and 24 hours after the first dose, and 48 hours after completion of therapy. Levels of L-selectin, leukocyte functional antigen 1 (LFA-1), Mac-1, and very late activation antigen 4 (VLA-4) expression were determined on alphabeta and gammadelta T cells and monocytes by dual-color immunofluorescent flow cytometry. Serum levels of soluble (s) L-selectin, sE-selectin, soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vascular cell adhesion molecule 1 (sVCAM-1) were measured by ELISA. There was a marked decrease in the T-cell and monocyte counts at 6 hours after therapy, with recovery to baseline at 24 to 48 hours. Adhesion molecule expression was normal on circulating T cells and monocytes in active MS. IVMP resulted in significant changes in the percent adhesion molecule expression on monocytes: increased L-selectin expression at 24 hours, decreased Mac-1 expression at 6 hours, and decreased VLA-4 expression at 6 hours and 24 hours following treatment. T-cell adhesion molecule expression was unaffected by the therapy. Serum sE-selectin was reduced at 6 hours and 24 hours following treatment. IVMP alters the distribution and kinetics of monocyte adhesion molecule expression and endothelial cell release of E-selectin, which may limit monocyte recruitment to areas of tissue destruction in MS.  相似文献   

11.
Bovine herpes virus-1 (BHV-1) infection appears to decrease the rate of polymorphonuclear leukocyte (PMN) influx into the lung in response to the secondary invader, Pasteurella haemolytica. It was postulated that BHV-1 may affect the rate of cellular infiltration by altering the function of the endothelium, thereby preventing PMN movement across the blood-tissue barrier. Therefore, we decided to investigate the effect of BHV-1 on the ability of PMN to adhere to lung endothelial cells (LEC). LEC were isolated from fetal bovine fetal tissue and were shown to function in PMN adhesion assays. Furthermore, enhanced PMN adhesion was observed after exposure of LEC to recombinant bovine TNF-alpha (rBoTNF-alpha) for 4, 8, 12, and 24 h. LEC infected with BHV-1 were shown to be less responsive to rBoTNF-alpha. However, infection of LEC with BHV-1 at an multiplicity of infection (MOI) of 1.0 or 10 did not affect basal levels of PMN adhesion to these cells. Decreased PMN binding to BHV-1-infected LEC, simultaneously treated with rBoTNF-alpha, was observed at 10-12 h post-infection. The data suggest that BHV-1 may prevent cytokine-induced PMN infiltration of the lung through the modification of EC responses to cytokines.  相似文献   

12.
TNF-alpha is known to elicit a rapid increase in the expression of specific endothelial cell adhesion molecules (ECAMs) within different vascular beds. The aim of this study was to determine whether lymphocytes contribute to the increased ECAM expression elicited by TNF-alpha. A dual radiolabeled mAb technique was used to quantify constitutive and TNF-alpha-induced expression of ICAM-1, VCAM-1, E-selectin, and P-selectin in different vascular beds (lung, heart, stomach, mesentery, small intestine, large intestine, and muscle) in wild-type and SCID mice. In reconstitution experiments, either whole splenocytes, T cell-enriched splenocytes, or B cell-enriched splenocytes were injected into SCID mice 48 h before TNF-alpha administration. Although the constitutive expression of ECAMs differed only slightly between wild-type and SCID mice, TNF-alpha-induced ECAM expression was markedly blunted in SCID mice compared with wild-type mice. This blunted response to TNF-alpha was also demonstrated for VCAM-1 in recombination activating gene (RAG)-1 mutant mice. Reconstitution studies revealed that administration of 50 x 10(6) splenocytes in SCID mice at 48 h before cytokine treatment restored the TNF-alpha-induced expression of VCAM-1 to levels normally observed in wild-type mice. Reconstitution with T cell- but not B cell-enriched splenocytes, also restored the TNF-alpha-induced expression of VCAM-1 in SCID mice to wild-type levels. These results implicate circulating T lymphocytes as modulators of the increased ECAM expression elicited by TNF-alpha.  相似文献   

13.
1. The characteristic features of the endothelium-mediated regulation of the electrical and mechanical activity of the smooth muscle cells of cerebral arteries were studied by measuring membrane potential and isometric force in endothelium-intact and -denuded strips taken from the rabbit middle cerebral artery (MCA). 2. In endothelium-intact strips, histamine (His, 3-10 microM) and high K+ (20-80 mM) concentration-dependently produced a transient contraction followed by a sustained contraction. Noradrenaline (10 microM), 5-hydroxytryptamine (10 microM) and 9,11-epithio-11, 12-methano-thromboxane A2 (10 nM) each produced only a small contraction (less than 5% of the maximum K+-induced contraction). 3. N(G)-nitro-L-arginine (L-NOARG, 100 microM), but not indomethacin (10 microM), greatly enhanced the phasic and the tonic contractions induced by His (1-10 microM) in endothelium-intact, but not in endothelium-denuded strips, suggesting that spontaneous or basal release of nitric oxide (NO) from endothelial cells potently attenuates the His-induced contractions. Acetylcholine (ACh, 0.3-3 microM) caused concentration-dependent relaxation (maximum relaxation by 89.7 +/- 7.5%, n=4, P<0.05) when applied to endothelium-intact strips precontracted with His. L-NOARG had little effect on this ACh-induced relaxation (n=4; P<0.05). Apamin (0.1 microM), but not glibenclamide (3 microM), abolished the relaxation induced by ACh (0.3-3 microM) in L-NOARG-treated strips (n=4, P<0.05). 4. In endothelium-intact tissues, His (3 microM) depolarized the smooth muscle membrane potential (by 4.4 +/- 1.8 mV, n = 12, P < 0.05) whereas ACh (3 microM) caused membrane hyperpolarization (-20.9 +/- 3.0 mV, n = 25, P< 0.05). The ACh-induced membrane hypepolarization persisted after application of L-NOARG (-23.5 +/- 5.9 mV, n=8, P<0.05) or glibenclamide (-20.6 +/- 5.4 mV, n=5, P<0.05) but was greatly diminished by apamin (reduced to - 5.8 +/- 3.2 mV, n = 3, P< 0.05). 5. Sodium nitroprusside (0.1-10 microM) did not hyperpolarize the smooth muscle cell membrane potential (0.2 +/- 0.3 mV, n=4, P>0.05) but it greatly attenuated the His-induced contraction in endothelium-denuded strips (n-4, P<0.05). 6. These results suggest that, under the present experimental conditions: (i) spontaneous or basal release of NO from endothelial cells exerts a significant negative effect on agonist-induced contractions in rabbit MCA, and (ii) ACh primarily activates the release of endothelium-derived hyperpolarizing factor (EDHF) in rabbit MCA.  相似文献   

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Fibrinogen mediates endothelial cell adhesion, spreading, and angiogenesis through integrin alphavbeta3. Previous studies by several investigators have suggested that the Arg-Gly-Asp (RGD) site at position 572-574 on the alpha chain of human fibrinogen can bind to alphavbeta3. However, this RGD sequence is absent in fibrinogen from most other species, including bovine, hamster, monkey, mouse, pig, and rat fibrinogen. In these species, an RGD site exists at the equivalent of position alpha252-254, which has the sequence RGG in humans. In addition, the role of an integrin binding site on the gamma chain at position 400-411 has been an issue of controversy. In the present studies, recombinant fibrinogen molecules with mutations in the potential endothelial cell binding sites have been used to test the role of these sites directly. The results show that the RGD at alpha572-574 is the primary adhesion site, and that the gamma chain site plays no significant role. Human and bovine plasma fibrinogens were also assayed for their ability to support adhesion of human and bovine vascular endothelial cells. The results show that although the two types of fibrinogen have RGD sequences at widely divergent sites, there is no significant difference in their ability to support endothelial cell adhesion. Furthermore, a chimeric human fibrinogen molecule with an RGD sequence at the bovine site, position alpha252-254, also supported adhesion. These results indicate that an RGD site in human fibrinogen at either position alpha252-254 or position alpha572-574 can mediate endothelial cell adhesion.  相似文献   

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It was studied the behaviour of fuel hot particles (analogous to Chernobyl) in gastrointestinal tract of cows. The values of caesium and strontium radionuclides transfer to the cows organism and its transition parameters to milk after the single per oral intake to the organism of animals are estimated. It is shown, that the biological simplicity of radionuclides in the fuel hot particles at two parameters lower, than the same radionuclides in washed phases.  相似文献   

18.
Myocardial injury after ischemia (I) and reperfusion (R) is related to leukocyte activation with subsequent release of cytokines and oxygen-derived free radicals as well as complement activation. In our study, the cardioprotective effects of exogenous C1 esterase inhibitor (C1 INH) were examined in a rat model of myocardial I + R (i.e., 20 min + 24 hr or 48 hr). The C1 INH (10, 50 and 100 U/kg) administered 2 min before reperfusion significantly attenuated myocardial injury after 24 hr of R compared to vehicle treated rats (P < .001). Further, cardiac myeloperoxidase activity (i.e., a marker of PMN [polymorphonuclear leukocyte] accumulation) in the ischemic area was significantly reduced after C1 INH treatment compared to vehicle treated animals (0.81 +/- 0.1, 0.34 +/- 0.13, 0.13 +/- 0.1 vs. 1.44 +/- 0.3 U/100 mg tissue, P < .001). In addition, C1 INH (100 U/kg) significantly attenuated myocardial injury and neutrophil infiltration even after 48 hr of reperfusion compared to vehicle treatment. Immunohistochemical analysis of ischemic-reperfused myocardial tissue demonstrated activation of classical complement pathway by deposition of C1q on cardiac myocytes and cardiac vessels. In addition, expression of the endothelial adhesion molecules P-selectin and intercellular adhesion molecule 1 (ICAM-1) was observed after reperfusion of the ischemic myocardium. In this regard, C1 INH administration abolished expression of P-selectin and ICAM-1 on the cardiac vasculature after myocardial ischemia and reperfusion. Blocking the classical complement pathway by exogenous C1 INH appears to be an effective means to preserve ischemic myocardium from injury after 24 and 48 hr of reperfusion. The mechanisms of this cardioprotective effect appears to be due to blocking of complement activation and reduced endothelial adhesion molecule expression with subsequent reduced PMN-endothelium interaction, resulting in diminished cardiac necrosis.  相似文献   

19.
To investigate the origin of intercellular adhesion molecule-1 (ICAM-1) and its expression on brain endothelial cells, we studied the expression in vitro of ICAM-1 on human brain endothelial cells after incubation of T cells from patients with multiple sclerosis (MS) using a histochemical technique and flow cytometry. We determined soluble forms of ICAM-1 (ICAM-1) in the supernatants after mixtures of brain endothelial cells and T cells from patients with MS using an enzyme-liked immunosorbent assay. Flow cytometric analysis showed that a number of ICAM-1-positive cells were significantly increased after incubation of brain endothelial cells with T cells from patients with acute relapsing MS during an exacerbation as compared with those of controls (P < 0.01). Patients with acute relapsing MS during an exacerbation and chronic progressive MS exhibited higher levels of ICAM-1 in the supernatants of mixtures with brain endothelial cells and lymphocytes than those of controls (P < 0.001 and P < 0.01, respectively). These results suggest that lymphocytes from patients with acute relapsing MS during an exacerbation lead to an increased expression of ICAM-1 on the brain endothelial cells and add to evidence involving this adhesion molecule in the pathogenesis of MS.  相似文献   

20.
This study was performed to clarify the possibility of visualization and quantification with 99mTc-tetrofosmin (Tf) myocardial scintigraphy in cases with a large atrium demonstrated by trans-thoracic echocardiography (TTE). Myocardial SPECT was evaluated in 4 patients with mitral stenosis and 15 patients with mitral regurgitation. Left atrium was identified in 12 out of 19 cases from an antero-posterior projection. The Tf uptake ratio of the left atrium, which was defined as the ratio of ROI count of the left atrium divided by the ROI count of the left ventricle, showed a good correlation with the left atrial area obtained by both trans-thoracic and trans-esophageal echocardiography (r = 0.88 and 0.91, respectively), These data suggest that Tf myocardial SPECT is a useful method of evaluating left atrial enlargement.  相似文献   

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