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1.
AIM: To observe the antiproliferative effect of c-myc antisense oligonucleotide in rat thymus lymphocytes. METHODS: Rat thymus lymphocytes were separated by Ficoll-Urografin density gradient centrifugation. Lipofectin was used to introduce antisense, sense and mismatched oligonucleotides for c-myc to rat thymus lymphocytes. The antiproliferative effect was assayed by incorporation of [3H]-TdR and MTS cell proliferation assay. TR-PCR was used to detect the expression of c-myc mRNA. RESULTS: c-myc antisense oligonucleotide inhibited ratthymus lymphocytes proliferation[(0.14±0.03)A vs(0.32±0.16)A,P<0.05],but this ef ect had no relationship with the concentration of c-myc antisense oligonucleot ide.c-myc antisense oligonucleotide decreased the expression of c-myc mRNA in rat thymus lymphocytes. CONCLUSION: c-myc antisense oligonucleotide inhibited rat thymus lymphocyte proliferation.  相似文献   
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AIM: To investigate the effect of uric acid on the maturation and the biological function of murine bone-marrow derived dendritic cells (BMDCs) in vitro.METHODS: BMDCs were cultured with GM-CSF, IL-4, LPS and uric acid. Cell phenotypes were analyzed by flow cytometry. MTT was used to detect the effect of uric acid on the function of BMDCs in stimulating the proliferation of T cells. IL-12 released by BMDCs was also detected. RESULTS: BMDCs were cultured and identified. Uric acid at concentrations of 200 mg/L and 400 mg/L increased the expression of the molecules (CD11c, CD83, CD86, IA/IE) on BMDCs surface and the IL-12 level in the culture supernatants (P<0.05), promoted the proliferation of T cells at the T: DC rate 5∶1, 10∶1, 20∶1 (P<0.05). However, uric acid at concentration of 70 mg/L had no effect on above molecule expression (P>0.05), no effect on T cell proliferation with BMDCs (P>0.05) was observed. CONCLUSION: Uric acid promotes the differentiation, maturation, the expression of co-stimulatory molecules, the IL-12 production in BMDCs and enhances the ability of BMDCs to stimulate the proliferation of T cell in a specical dose range.  相似文献   
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Johne's disease (JD) is a costly intestinal disease of ruminants caused by Mycobacterium avium subspecies paratuberculosis (Map), which is transmitted to perinatal calves by the fecal-oral route. Disease control efforts focus on identification and culling of infected cattle from herds; therefore failure to identify animals early is a major obstacle to reducing transmission. Development of host immunity during early JD remain incompletely characterized so detecting subclinical JD using immunologic techniques is a substantial challenge in the field. Development of a test with high sensitivity and specificity is a major research goal with significant implications for the cattle industry. The objectives of this study were to compare early Map-specific T lymphocyte responses in naive, experimentally Map infected and Map vaccinated calves using a subcutaneous matrigel biopolymer-based assay. We examined the phenotype of recruited lymphocytes and local interferon gamma (IFNγ) production within subcutaneously placed matrigel containing Map antigen 30 days after experimentally induced intestinal Map infection or Map vaccination. We show that IFNγ-secreting CD4+ T cells are recruited to matrigel sites in vaccinated but not infected or naïve calves. γδ T cells recruited to matrigel sites of Map-infected calves were mostly WC1-, while γδ T cells recruited to matrigel sites of Map-vaccinated calves were predominantly WC1+. IFNγ at matrigel sites was a discriminating factor between infected calves, naïve calves and vaccinated calves. These data contribute to our understanding of early anti-Map immunity, and may be useful for detecting early intestinal Map infections in calves or for enhancing our ability to discriminate between Map-infected and Map-vaccinated calves.  相似文献   
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AIM:To isolate and purify the active components from Centella asiatica, and to observe their effect on the proliferation and apoptosis of mouse spleen lymphocytes. METHODS:Semi-preparative high-performance liquid chromatography was performed to further isolate and purify the extracts from Centella asiatica. The effects of the active components on apoptosis and mitochondrial membrane potential of the spleen lymphocytes were assessed by flow cytometry. The structures of the active components were identified by ultraviolet spectrometry, electrospray ionization negative-ion mass spectrometry, [1H] nuclear magnetic resonance (NMR) and [13C] NMR. RESULTS:The molecular weights of the active components from Centella asiatica, named compound I and compound II, were 302 and 286, respectively. The compound I and compound II from Centella asiatica significantly inhibited the proliferation, promoted the apoptosis and reduced the mitochondrial membrane potential of mouse spleen lymphocytes. Compound I and compound II were identified as quercetin and kaempferol. CONCLUSION:The compound I and compound II from Centella asiatica show antiproliferative and immunosuppressive effects on mouse spleen lymphocytes by promoting apoptosis and reducing mitochondrial membrane potential.  相似文献   
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AIM: To investigate the effect of anti-Sonic hedgehog(Shh) blocking antibody on the killing effect of peripheral blood mononuclear cells(PBMCs) on cervical carcinoma HeLa cells. METHODS: The expression levels of Shh and Shh signaling molecules in HeLa cells were detected by immunocytochemistry and RT-PCR. PBMCs from health peoples were isolated by the method of Ficoll density gradient centrifugation, and then co-cultured with HeLa cells in vitro. The expression of CD3, CD69 and CD71 was assayed by flew cytometry. The concentrations of IFN-γ, IL-10 and IL-4 in culture supernatants were detected by ELISA. The killing effect of PBMCs on HeLa cells was observed under microscope. RESULTS: Shh and Shh signaling molecules were expressed in HeLa cells. The level of Shh expression didn't change significantly in the 6th passage of HeLa cells. CD3+ cells were increased in the co-culture system. The expression of CD69 and CD 71, and the secretion of IFN-γ were increased, while the secretion of IL-10 was decreased in the co-culture system treated with anti-Shh blocking antibody. Anti-Shh blocking antibody has no effect on the secretion of IL-4. The killing effect of PBMCs on HeLa cells was strengthened by anti-Shh blocking antibody. CONCLUSION: Anti-Shh blocking antibody promotes the activation of PBMCs and enhances the killing effect of PBMCs on cervical carcinoma HeLa cells.  相似文献   
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The purpose of this work was to define more precisely the role of Ureaplasma organisms in the aetiology of granular vulvovaginitis and balanoposthitis (GVVBP) of cattle. To contribute to this question the frequency and degree of infection with Ureaplasmas in two main groups of cattle was taken into account: (a) in cattle with symptoms of the mentioned disease, (b) in cattle without clinical symptoms. The samples of semen from 301 sires with symptoms of GVVBP and from 43 healthy sires as also vaginal mucus swabs from 96 cows with GVVBP and from 40 cows mated by the sire infected with Ureaplasma organisms and from 50 cows inseminated with semen which contained Ureaplasma organisms were taken for bacteriological examinations. The control group in relation to the above mentioned cows constituted of 22 heifers free from symptoms of GVVBP and neither inseminated nor mated naturally. It has been shown that on an average 78.1% of sires with pathological changes in the mucosa of the penis or prepuce and only 25.6% of healthy sires were infected with Ureaplasma organisms. The concentration of Ureaplasma organisms was also significantly higher in material obtained from sires with symptoms of the disease than in that from healthy animals. Ureaplasma organisms were demonstrated more frequently (72.7%) in cows with GVVBP than in cows without these symptoms (13.3%). Similarly, as in the material obtained from sires, in the material taken from cows with symptoms of the disease the concentration of Ureaplasma organisms was significantly higher than that in the material originating from the healthy cows. The obtained findings may indicate that Ureaplasma organisms play a role in the aetiology of GVVBP.  相似文献   
9.
AIM: To explore the effects of aflatoxin G1(AFG1 )on proliferation and TNF-α secretion of human peripheral blood mononuclear cells(HPBM) in vitro. METHODS: The effects of AFG1 on proliferation of HPBM were analysed with flow cytometric (FCM) DNA analysis and MTT bioassay, while that on TNF-α secretion was detected with ELISA.RESULTS: FCM analysis revealed that 6 h after treatment, proliferation index(PI) of 1000 μg/L AFG1 treated HPBM was significantly higher than that of control. 24 h after AFG1 treatment, stimulating effects on proliferation was found in HPBM treated with AFG1 at 200 μg/L and 1 000μg/L.Regression analysis showed that PI was postively correlated with the concentrations of AFG1 in the concentration range from 0 to 1 000μg/L( r=0. 5122 and 0.5119 respectively,P<0.05).MTT bioassay showed that the A value of the cells treated with AFG1 at 2 000 μg/L was higher than that of the control. Double antibody sandwich enzyme linked immunosorbent assay (ELISA) results showed that AFG1 at a dose of 100 μg/L could significantly inhibit lipopolysaccharide-induced TNF-α secretion.CONCLUSION: AFG1 could stimulate the proliferation of HPBM and could decrease TNF-α secretion at certain concentration.  相似文献   
10.
The bacteriologic, immunologic, and clinical responses of 3- to 4-month old Holstein-Friesian calves to experimental exposure with Moraxella bovis type 10900 has been investigated. After u.v. radiation and intraconjunctival exposure with 1.9 × 107 microorganisms, each eye of 16 calves exhibited signs of blepharospasm, photophobia, and increased lacrimation. Bacteria were recovered from exposed eyes for 2–7 consecutive weeks before maximal clinical response occurred. The severity of the cases varied from eyes that exhibited mild signs to severe clinical cases with profuse lacrimation, conjunctival swelling, corneal opacity, and ulceration. By 70 days after exposure, M. bovis could not be recovered from any conjunctival swabs, and clinical signs were not observed. Four non-exposed control animals did not develop clinical signs nor was M. bovis recovered from conjunctival swabs.Lacrimal secretions collected at the time of and 1 week after maximal clinical response had significantly elevated levels of total protein as compared to those collected 3, 2, and 1 week before, and 2 and 3 weeks after maximal clinical response. A passive hemagglutination test, using tanned formalized sheep erythrocytes sensitized with M. bovis sonicate antigen, detected antibody in lacrimal secretions from 22 of 32 eyes. The appearance of specific antibody in lacrimal secretions correlated with the amelioration of clinical signs and the decline in numbers of M. bovis microorganisms recovered from conjunctival swabs.  相似文献   
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