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1.
The effect of original analogues of the 6-9 C-terminal AVP fragment, D-MRP and D-MPRG, on the active avoidance behaviour of rats was studied using intranasal administration in a wide range of doses. The dose in 0.1 mcg/kg was the most efficient for D-MPR and 0.01 mcg/kg for D-MPRG, which for the tripeptide was ten times, and for the tetrapeptide hundred times lower than the corresponding dose of AVP used in the similar experiments. The tri- and tetrapeptide were shown to facilitate the active avoidance behaviour affecting both the formation of the reaction and consolidation of memory trace. The peptides mostly affect the perception processes, i.e., the detection of a specific stimulus from the environment, the estimation and memorizing of its biological significance.  相似文献   

2.
A newly synthesized demethylpodophyllotoxin derivative, 4-O-butanoyl-4'-demethylpodophyllotoxin (BDPT) or BN58705, has recently been shown to exert a potent cytotoxic activity in vitro against a variety of drug-resistant human tumor cell lines. The effect of this agent on effector cells of the immune system, however, has not been examined. The present study investigated the effect of BDPT on the response of activated human peripheral blood derived monocytes (PBM) to secrete cytokines. Activation of PBM overnight with LPS, IFN-gamma, or PMA resulted in secretion into the supernatant of TNF-alpha, IL-1 beta, IL-6, and IL-8 as assessed by ELISA. The addition of BDPT to the stimulated cultures resulted in significant inhibition of TNF-alpha and IL-1 beta secretion, whereas the secretion of IL-6 and IL-8 was not affected. The selective inhibition of TNF-alpha and IL-1 beta secretion by BDPT-treated PBM was observed with all three stimuli tested. The inhibitory effect mediated by BDPT was concentration dependent and was optimal at 6-20 microM. Time kinetic analysis indicated that the inhibition of secretion was rapid and detected as soon as 2 hr following stimulation of the PBM and lasted for as long as 24 hr. A comparison was made between BDPT and pentoxyfilline, a xanthine-derived phosphodisterase inhibitor that was reported to inhibit TNF-alpha and IL-1 beta secretion by PBM. Both BDPT and PTX showed similar time kinetics and patterns of inhibition.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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Metallothionein (MT) synthesis induced by the inflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF), was studied in vivo. Administration of recombinant human IL-6 or TNF to rats caused the acute phase responses including rapid decreases in plasma zinc (Zn), and increases in plasma copper (Cu) and ceruloplasmin. Hepatic concentration of MT-I, one of MT isoforms, began to increase within 3 h after the injection of IL-6 or TNF. In IL-6-treated rats, MT-I concentration in liver reached a maximum level at 12 h and decreased with a transient rebound, whereas, in TNF-treated rats, a high level of MT-I lasted for about 48 h. MT-II, the other MT isoform, was induced more than MT-I in liver by both cytokines. MT-I was also induced in lung and heart by TNF, but little by IL-6. The data suggest that IL-6 may be responsible for MT synthesis in liver, whereas TNF may be responsible not only in liver but also in lung and heart. Furthermore plasma concentration of MT did not always reflect the enhanced concentration of MT by TNF and IL-6 in liver, suggesting involvement of many factors influencing plasma MT levels. The interrelation between IL-6 and TNF for MT synthesis has also been discussed.  相似文献   

7.
BACKGROUND: Microalbuminuria is an early marker of prognostic significance in diabetic renal disease. However, testing for microalbuminuria in a timed sample of urine using the double antibody radioimmunoassay (RIA) method is cumbersome and requires special laboratory facilities. Recently, a test strip for microalbuminuria, the Micral Test was available and we evaluated the performance of this test strip as a screening method for detection of microalbuminuria. METHODS: One hundred consecutive diabetic patients who were tested to be dipstick-negative (Albustix) for proteinuria were enrolled for the study. Micral Tests were performed on a paired first morning and random urine specimen from the same patient and the results compared with a timed 24-hour urine measurement of urine albumin excretion using the RIA method. RESULTS: Eighteen specimens were tested positive by the RIA method with a urinary albumin range of 32-177 mg/24 hours. With the Micral Test, the following sensitivity, specificity, positive and negative predictive values were obtained: 66.7%. 97.6%, 85.7% and 93.0% for the first morning urine specimens, and 77.8%, 91.5%, 66.7% and 94.9% for the random urine specimens. CONCLUSIONS: These results suggest that Micral Test with either the first morning or random urine specimen offers a simple, reliable, rapid and convenient method for screening of microalbuminuria in the diabetic patient.  相似文献   

8.
Increased airway resistance and airway hyperresponsiveness induced in rats by infection with parainfluenza type I (Sendai) virus is associated with bronchiolar fibrosis. To determine whether increased tumor necrosis factor (TNF)-alpha gene expression is an important regulatory event in virus-induced bronchiolar fibrosis, pulmonary TNF-alpha mRNA and protein expression was assessed in rat strains that are susceptible (Brown Norway; BN) and resistant (Fischer 344; F344) to virus-induced bronchiolar fibrosis. Virus-inoculated BN rats had increased TNF-alpha pulmonary mRNA levels (P < 0.05) and increased numbers of bronchiolar macrophages and fibroblasts expressing TNF-alpha protein compared with virus-inoculated F344 rats (P < 0.05). Virus inoculation also induced elevated TNF-alpha mRNA and protein levels (P < 0.05) in cultured rat alveolar macrophages (NR8383 cells). A 55-kd soluble TNF receptor-immunoglobulin G fusion protein (sTNFR-IgG) was used to inhibit TNF-alpha bioactivity in virus-inoculated BN rats. Treated rats had fewer proliferating bronchiolar fibroblasts, as detected by bromodeoxyuridine incorporation, compared with virus-inoculated control rats (P < 0.05). There was also increased mortality in p55sTNFR-IgG-treated virus-inoculated rats associated with increased viral replication and decreased numbers of macrophages and lymphocytes in bronchoalveolar lavage fluid (P < 0.05). The results of this study indicate that 1) Sendai virus can directly up-regulate TNF-alpha mRNA and protein expression in macrophages, 2) TNF-alpha is an important mediator of virus-induced bronchiolar fibrosis, and 3) TNF-alpha has a critical role in the termination of Sendai viral replication in the lung.  相似文献   

9.
OBJECTIVE: Our purpose was to test the hypothesis that neonates who develop bronchopulmonary dysplasia have higher amniotic fluid concentrations of proinflammatory cytokines than those who do not develop bronchopulmonary dysplasia. STUDY DESIGN: The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmonary dysplasia in the neonate was examined in 69 patients who were delivered of preterm neonates (< or = 33 weeks) within 5 days of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS: Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of newborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 concentrations were significantly higher in mothers whose infants had bronchopulmonary dysplasia than in mothers whose infants did not have bronchopulmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmonary dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The differences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth (p < 0.05 for each). CONCLUSIONS: (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of neonates may begin before birth.  相似文献   

10.
Lipopolysaccharide (LPS) and homologous cytokines were tested for their effect on core temperature in mice using battery-operated telemetric devices placed in the peritoneal cavity. One microgram LPS injected intraperitoneally (i.p.) induced a biphasic effect on core body temperature (Tc), a rapid decrease in Tc with a peak around 30-45 min followed by a prolonged rise around 150-300 min. When a higher dose of LPS (5 microg) was used, the hypothermia was increased in magnitude and lasted much longer, and no fever was observed. Both the decrease and the increase in Tc caused by LPS were prevented by pretreating the mice with indomethacin, a cyclooxygenase inhibitor, but not by a nitric oxide synthase inhibitor. Mouse interleukin-1beta (mIL-1beta, 100 ng, i.p.) induced changes resembling those to LPS, a short-lived decrease in Tc, followed by a small increase. When 1 microg mIL-1beta was injected a profound hypothermia lasting more than 3 h was observed. Mouse IL-6 (1 microg) failed to alter core temperature after either intravenous (i.v.) or i.p. administration. Human IL-6 was also ineffective. Recombinant mouse tumor necrosis factor-alpha (mTNFalpha) also failed to alter the core temperature of mice when injected at a dose of 1 microg (i.p. or i.v.). However, a higher dose of mTNFalpha (5 microg i.p.) caused a short-lived decrease in Tc, followed by a small increase. Similar results were obtained with LPS and the cytokines in C57Bl/6J mice, except that mIL-1beta was ineffective in this strain. These results indicate that the endocrine, neurochemical and behavioral responses to IL-1, IL-6 and TNFalpha administration cannot be explained by changes in Tc, although they may contribute to them. They also suggest that IL-1beta may account for the fever observed following LPS, but that these cytokines are probably not the only factors involved in LPS-induced changes in Tc.  相似文献   

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In this study we determined, in patients with multiple myeloma (MM), serum levels of IL-4 and IL-6 at diagnosis and during the course of the disease, seeking a correlation with disease activity and prognosis. We studied 54 MM patients, 41 of whom responded to chemotherapy whilst 11 were resistant. At diagnosis, IL-6 was increased in 66% of patients (median 35.5 pg/ml) whereas IL-4 was low (median 4 pg/ml) in 75% of patients. In responding patients, IL-4 increased in remission (median 25 pg/ml), whereas IL-6 decreased (median 4 pg/ml). In chemotherapy-resistant patients, IL-6 and IL-4 values remained stable during the course of the disease.  相似文献   

12.
Tumor necrosis factor alpha (TNF-alpha) may play a central role in the disease pathogenesis which occurs as a consequence of chlamydial infection. To investigate the importance of TNF-alpha gene promoter polymorphisms and TNF-alpha levels in tear fluid in scarring trachoma, a large matched-pair case-control study was performed in The Gambia. The -308A allele was present in a higher proportion of patients (28.4%) than controls (18.4%), with an increasing association for homozygotes (chi2 for trend, P = 0.032; allele frequency, 0.163 in patients and 0.099 in controls; chi2, P = 0.025). For the -238A allele, the association was similar but not significant. The disease association was highly significant when the number of either -308A or -238A sites in an individual was considered (P = 0.003). TNF-alpha promoter alleles are tightly linked to some HLA class I and II alleles, but multivariate analysis confirmed that the disease associations were independent of HLA, although a class I allele, A*6802, is also associated with disease. TNF-alpha was more frequently detected in tear samples from patients (27.6%) than from controls (15.9%), increasingly so for higher levels of detectable TNF-alpha (P = 0.015). Among patients, detectable TNF-alpha in tears was highly associated with the presence of ocular chlamydial infection (P < 0.001). The results indicate that TNF-alpha plays a major role in the tissue damage and scarring which occurs as a consequence of Chlamydia trachomatis infection.  相似文献   

13.
Interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha) induce a motogenic response in a number of benign and malignant cells. We examined the chemokinetic effects of these cytokines on the cell migration of four melanoma cell lines on fibronectin using modified Boyden chambers and video-time lapse analysis. Flow cytometry analysis of IL-1 receptors, TNF receptors, and shifts in beta 1 integrin expression were correlated with the effects of these cytokines on cell migration on fibronectin. The four melanoma cell lines exhibited heterogeneous expression of types I and II IL-1 receptors as well as p60 TNF receptors. Scant p80 TNF receptor expression was detected on only one cell line. Three of four melanoma cell lines demonstrated type I IL-1 receptors by Western blotting. IL-1 alpha and TNF-alpha induced heterogeneous modulation of beta 1 integrin expression in the four melanoma cell lines tested; downward shift of the alpha 2, alpha 3, alpha 4, and beta 1 integrin subunits was detected among three of the melanoma cell lines as were upward shifts of the alpha 4, alpha 5, and alpha 6 integrin subunits among three of the melanoma cell lines. IL-1 alpha and TNF-alpha induced enhanced migration on fibronectin in one of the melanoma cell lines and were related to an upward shift in the alpha 4 and alpha 5 integrin subunit expression. Taken together, the findings indicate that expression of a particular receptor for IL-1 or TNF does not necessarily signal a motogenic response in melanoma cells, but induces heterogeneous shifts in beta 1 integrin expression. However, upregulation in alpha 4 and alpha 5 integrin subunits appears to relate to enhanced migration on fibronectin.  相似文献   

14.
The pathogenesis of PTH-induced bone loss is uncertain. Experimental evidence suggests that PTH induces the production by osteoblasts of the bone-resorbing cytokine, interleukin-6. We measured the circulating levels of interleukin-6, tumor necrosis factor-alpha, and interleukin-1 beta and examined their relationship to biochemical markers of bone turnover in 38 patients with primary hyperparathyroidism (7 of whom also were studied after successful parathyroid adenomectomy), 6 patients with hypoparathyroidism, and 12 subjects with normal parathyroid function. The patients with untreated primary hyperparathyroidism had mean serum levels of interleukin-6 that were 16-fold higher than control values (mean +/- SEM; primary hyperparathyroidism 18.6 +/- 2.1 pg/mL, controls 1.1 +/- 0.1; P < 0.001). Circulating levels of interleukin-6 soluble receptor (primary hyperparathyroidism 41.7 +/- 1.2 ng/ mL, controls 25.1 +/- 1.0; P < 0.001), and tumor necrosis factor-alpha (primary hyperparathyroidism 11.6 +/- 0.8 pg/mL, controls 2.5 +/- 0.2; P < 0.001) were also elevated. After successful parathyroid adenomectomy, levels of each of these cytokines fell into the normal range. The mean levels of interleukin-6, its soluble receptor, and tumor necrosis factor-alpha in the subjects with hypoparathyroidism were lower than control values (P < 0.001 for each variable). There was no difference between subjects with primary hyperparathyroidism and controls in the circulating level of interleukin-1 beta. In the subjects with untreated primary hyperparathyroidism, serum levels of interleukin-6 correlated strongly with those of intact PTH (r = 0.47, P = 0.003) and biochemical markers of bone resorption: serum deoxypyridinoline (r = 0.93, P < 0.001), serum type I collagen carboxyterminal telopeptide (r = 0.87, P < 0.001), urinary pyridinoline (r = 0.81, P < 0.001), and urinary deoxypyridinoline (r = 0.63, P = 0.005). Levels of tumor necrosis factor-alpha correlated less strongly with the same variables: PTH (r = 0.41, P = 0.01), serum deoxypyridinoline (r = 0.48, P = 0.002), serum type I collagen carboxyterminal telopeptide (r = 0.46, P = 0.004), urinary pyridinoline (r = 0.61, P = 0.008), and urinary deoxypyridinoline (r = 0.61, P = 0.007). Levels of interleukin-6 also correlated with those of tumor necrosis factor-alpha (r = 0.44, P = 0.005). Multiple regression analysis indicated that interleukin-6, but not tumor necrosis factor-alpha, was independently predictive of bone resorption. We conclude that serum levels of interleukin-6 and tumor necrosis factor-alpha are increased in patients with primary hyperparathyroidism and are normalized by successful surgical treatment. The finding that these cytokines correlate with biochemical markers of bone resorption suggests that they play a role in the pathogenesis of bone loss in primary hyperparathyroidism.  相似文献   

15.
Levels of plasma TNF-alpha, interleukin-1beta(IL-1beta ), soluble TNF-receptor I (sTNF-R I) and soluble TNF-receptor II (sTNF-R II) were determined in 16 critically burned patients. Seven of the 16 patients showed hypovolemic shock (shock group), 9 with sepsis (sepsis group), 8 with multiple organ dysfunction syndrome (MODS group) and 6 of them died (non-survival group). Plasma TNF-alpha, sTNF-R I and R II were significantly higher in the shock group, the MODS group and the non-survival group than each of the control groups. TNF-alpha and sTNF-Rs increased gradually in the MODS group and the non-survival group from 1 to 5 days postburn. TNF-alpha, sTNF-R I and R II correlated positively with Goris' multiple organ failure score. Molecular sTNF-Rs/TNF-alpha ratios were lower in the sepsis group than in the non-sepsis group. These results suggest that circulating TNF and soluble TNF receptors system play an important role in the development of burn shock and MODS; high molecular ratios of endogenous sTNF-Rs might not reduce the morbidity of MODS and the mortality in critically burned patients.  相似文献   

16.
Because interferon-gamma (IFN gamma) is present in the central nervous system during neurologic diseases associated with inflammation, its effect on endotoxin-induced cytokines was studied. Cerebrospinal fluid (CSF) and serum levels of interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha (TNF alpha), their messenger RNA expression in brain areas (hypothalamus, hippocampus, and striatum) and in spleen were evaluated 2 and 8 h after endotoxin [lipopolysaccharide (LPS), 25 microg/rat i.c.v.], IFN gamma (2.5 microg/rat i.c.v.) or after their coadministration in rats. CSF and serum IL-1beta levels were increased by LPS alone and IFN gamma coadministration did not furtherly increase them. IFN gamma potentiated LPS effect on IL-6 and TNF alpha levels in both CSF and serum. LPS and IFN-gamma coadministration did not alter IL-1beta messenger RNA expression induced by LPS in brain areas and in spleen, but it potentiated that of IL-6 and TNF alpha. The present in vivo data show that i.c.v. coadministration of LPS and IFN gamma results in a potentiation of cytokine production (IL-6 and TNF alpha) which may trigger a cascade of events relevant to neurodegenerative processes. This action is independent of IL-1beta because the production of this cytokine is not altered by IFN gamma treatment.  相似文献   

17.
OBJECTIVES: Concentrations of tumour necrosis factor-alpha (TNF-alpha) were assayed by radioimmunoassay in serum samples collected between 1981 and 1987 from 111 patients with asbestosis who were at a high risk of cancer. Follow up of these patients until 1993 showed that 38 had developed cancer (27 lung, three mesotheliomas, and eight diverse malignancies). RESULTS: The mean serum concentrations of TNF-alpha given in fmol/100 microliters serum in all the cases with cancer (14.1) and the cases with lung cancer (13.6) were significantly higher (P < 0.05) than the mean concentrations in the exposed controls (10.5). A positive increase was considered to be any value that was > 2 SDs above the mean of the exposed controls. 22% (six of 27) of the cases with lung cancer were positive compared with 4% (three of 73) of the exposed controls, a significant difference (P < 0.001). The serum concentrations of TNF-alpha correlated moderately with cancer (r = 0.3), lung cancer (r = 0.3), and Neu oncoproteins and epidermal growth factor receptor (EGFR) (r = 0.3, 0.5 respectively). Also, there was a significant correlation between development of cancer and severity or progression of asbestosis. There was no correlation between the concentrations of TNF-alpha and severity or progression of asbestosis. CONCLUSIONS: These results showed high concentrations of TNF-alpha in the patients who had cancer. TNF-alpha may offer an auxiliary method in early diagnosis of cancers related to asbestosis.  相似文献   

18.
BACKGROUND: Proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) play an important role in the blood-brain barrier breakdown present in several neurological diseases including multiple sclerosis and AIDS. However, the specific effects of these cytokines on central nervous system-derived endothelial cells (CNS-EC) is not fully understood. In this study the effects of TNF-alpha and IL-6 were tested on different permeability mechanisms of CNS-EC. METHODS: Central nervous system endothelial cells were isolated from human brain and retina and cultured in vitro in a transwell system. Fluid-phase endocytosis and transcytosis, absorptive-mediated endocytosis, and ammonia diffusion were measured with specific methods. Endothelial cells were studied with electron microscopy for the ultrastructural effects of cytokine stimulation. RESULTS: Fluid-phase endocytosis and transcytosis were significantly increased by TNF-alpha and IL-6. This effect was dose dependent and reversible. The ammonia diffusion rate was also significantly increased by TNF-alpha. Absorptive-mediated endocytosis was not enhanced by TNF-alpha. Ultrastructural analysis of cytokine-treated CNS-EC confirmed the alterations in permeability showing an increase in endocytotic activity and a decrease in tight junctions. CONCLUSIONS: The proinflammatory cytokines IL-6 and TNF-alpha induce specific changes in the morphology and permeability of CNS-EC. These alterations can be important in many diseases characterized by increased cytokine production.  相似文献   

19.
Cytokines are known to play a role in T-cell lymphopoiesis as potent growth or differentiation factors, but many experiments focusing on their role in the thymus have been conducted only in vitro. We have thus used frozen sections obtained from fetal thymuses of normal C57BL 6 mice to investigate by immunohistochemistry the presence of interleukin-1 beta (I4-1 beta), IL-2. IL-4. IL-6. interferon-7 (IFN-7) and tumour necrosis facor-alpha (TNF-alpha). The results reveal that apart from IL-2, which was not detected, all these cytokines display a time-dependent expression pattern in the normal fetal thymus. First, production of IL-4, IL-6 and TNF-alpha is detected around days 13 14; this is followed by a second wave on days 16 17, with a production of IL-1 beta, IL-4 and IL-6, and finally, just before birth (day 19), by a third wave of IL-1 beta, IL-4, IL-6, IFN-7 and TNF-alpha production. This supports the hypothesis that cytokines play a rote in T-cell lymphopoiesis.  相似文献   

20.
S O'Neil  J Hunt  J Filkins  R Gamelli 《Canadian Metallurgical Quarterly》1997,122(2):281-6; discussion 286-7
BACKGROUND: Obstructive jaundice (OJ) predisposes patients to postoperative sepsis. We determined whether OJ led to an increased endotoxin stimulated tumor necrosis factor-alpha (TNF-alpha) production by macrophage-rich organs and whether a lack of intraluminal gut bile contributed to this increased sensitivity. METHODS: Rats underwent laparotomy and common bile duct ligation and division (CBDL) or sham operation after they were given low-dose endotoxin or saline solution (NS). TNF-alpha levels in plasma, perfusate from the isolated perfused rat liver, and tissue from lung, spleen, and liver were measured 90 minutes later. An additional group underwent creation of a choledochal-vesical fistula and endotoxin administration. RESULTS: The plasma TNF-alpha, liver perfusate TNF-alpha, and the tissue TNF-alpha levels in liver, lung, and spleen were significantly elevated in the CBDL + endotoxin (CBDL + ETX) group compared with the SHAM + ETX and CBDL + NS groups (p < 0.05). The choledochal-vesical fistula group after endotoxin had plasma TNF-alpha levels only 27% that of the CBDL + ETX group (p < 0.05). CONCLUSIONS: OJ sensitizes macrophage-rich organs to produce larger amounts of TNF-alpha in response to endotoxin. This sensitization is not solely due to decreased intraluminal gut bile.  相似文献   

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