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31.
P. Pellegrini Anna Maria Berghella T. Del Beato Sergio Cicia Domenico Adorno Carlo Umberto Casciani 《Cancer immunology, immunotherapy : CII》1996,42(1):1-8
Recent theories have established that, during an ongoing immune response, the lymphokines produced by TH1 and TH2 subsets
of CD4+ T cells are critical to the effectiveness of that response. In vivo and in vitro studies have demonstrated that the type
of environmental cytokines plays a determinant role in directing the development of naive T cells into TH1 or TH2 effector
cells. Disregulated expansion of one or other subset may contribute to the development of certain diseases. To establish whether
a similar situation might exist in the cells of the peripheral blood (PBMC) of colorectal cancer patients, we have performed
immunological studies on a group of patients and a group of healthy subjects. We examined the interleukin-2 (IL-2), interferon
γ (IFNγ), IL-4, IL-6 and tumour necrosis factor α levels in serum; the production of IL-4 and IL-2, with and without activating
agents, by PBMC, tumour-draining lymph node lymphocytes and tumour cells; and the proliferative response of PBMC to IL-2,
IL-4 and anti-CD3 monoclonal antibody (anti-CD3), which were variously combined. The data of the present study lead us to
hypothesize that, because of suppressive effects probably due to environmental IL-4, in the peripheral blood of patients there
seems to be a disregulation in the functionality of TH1 and TH2 subsets of CD4+ T cells, with an expansion in TH2 and a malfunction in TH1 cells. Moreover it seems that this disregulation increases with
as the disease progresses through the stages, suggesting that it can be directly implicated in the mechanisms that allow the
tumour to locate and progress in the host.
Received: 27 June 1995 / Accepted: 13 November 1995 相似文献
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The incidence of gallbladder cancer (GBC) is relatively rare but a high degree of malignancy. The migration and invasion potential of GBC severely affects the prognosis of patients with GBC. Glycochenodeoxycholate (GCDC) is one of the most important components in GBC-associated microenvironment. However, the role of GCDC in the metastatic feature of GBC cells is not fully understood. First, the results of this study found that GCDC could effectively enhance the metastasis of GBC cells. Furthermore, GCDC could lead to the enhancement of epithelial to mesenchymal transition (EMT) phenotype in GBC cells, which is concerned to be an important mechanism of tumor metastasis. Further studies showed that GCDC treatment induced the upregulation of matrix metalloproteinase-3 (MMP3), MMP9, and SOCS3/JAK2/p-STAT3 signal pathway in GBC cells, which could regulate the level of EMT. Beside that, we also found the positive expression of farnesoid X receptor (FXR) in GBC cells and inhibition of FXR could significantly block the effect of GCDC on the metastasis of GBC cells. These results indicated that GCDC promoted GBC cells metastasis by enhancing the level of EMT and inhibition of FXR could significantly block the effect of GCDC. On one hand, FXR might be an indicator for predicting the metastasis of patient with GBC. On the other hand, FXR might serve as a potential antimetastasis target in GBC therapy. 相似文献
34.
Miniscrews are used as orthodontic anchorage devices in the dentistry clinical practice but the in vivo metallic release from these structures has been not previously investigated. The aim of this study was to determine the content of Al, Co, Cr, Cu, Ni, Ti and V in oral mucosa cells of control subjects, patients under orthodontic treatment and with both, orthodontic treatment and miniscrew, in order to know the contribution of these mini-implants to the total metallic content. ICP-MS measurements revealed the following ascending order: Cr < Ni < Ti < Cu < Al, and Co and V were practically undetected. Significant differences in comparison to the control group were found for Cu in the orthodontic group, and for Ni in both, orthodontic and orthodontic + miniscrew groups. Potential correlations among metallic elements and with some clinical factors were also explored. These findings suggest that miniscrews do not increase significantly the metal release. 相似文献
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BackgroundSevere acute pancreatitis (SAP) is associated with high morbidity and mortality. Bone marrow mesenchymal stem cells (BMSCs) have shown obvious protective effect on SAP. However, little is known about the underlying mechanism. The objective of this study is to unravel the role and regulatory mechanism of miR-181a-5p in BMSCs-mediated pancreatic repair.MethodsBMSCs were isolated from Sprague-Dawley rats and characterized by flow cytometry and Oil Red O staining. Sodium taurocholate- and caerulein-induced models were used as SAP models in vivo and in vitro, respectively. Pancreatic injury were evaluated by H&E and histopathological analysis, as well as by measuring levels of amylase, lipase and cytokines. qRT-PCR and western blotting were performed to detect the level of miR-181a-5p and the protein levels of PTEN/Akt, respectively. ELISA was conducted to detect the levels of TNF-α, IL-1β, IL-6, angiopoietin, IL-4, IL-10 and TGF-β1. The apoptotic rate of AR42 J cells was quantitated by concurrent staining with Annexin-V-FITC and PI.ResultsBMSCs significantly attenuated pancreatic injury in SAP rats by reducing inflammatory infiltration and necrosis, and this effect was abolished by CXCR4 agonist AMD3100. ADM3100 exhibited more severe pancreatic injury and decreased miR-181a-5p levels in the pancreas and serum compared to SAP group. Overexpression of miR-181a-5p in BMSCs (BMSCs-miR-181a-5p) markedly potentiated the protective effect of BMSCs by reducing histological damage and levels of amylase and lipase. Moreover, BMSCs-miR-181a-5p dramatically reduced levels of angiopoietin, TNF-α, IL-1β and IL-6, but induced the levels of IL-4 and IL-10. In caerulein-treated AR42 J cells, co-culturing of BMSCs-miR-181a-5p alleviated caerulein-induced increase of amylase and lipase, and apoptosis via PTEN/Akt/TGF-β1 signaling.ConclusionBMSCs alleviate SAP and reduce inflammatory responses and apoptosis by secreting miR-181a-5p to target PTEN/Akt/TGF-β1 signaling. Hence, BMSCs-miR-181a-5p could serve as potential therapeutic target for SAP. 相似文献
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《Animal : an international journal of animal bioscience》2017,11(5):811-819
Angiogenin is a member of the ribonuclease A superfamily of proteins that has been implicated in stimulating angiogenesis but whether angiogenin can directly affect ovarian granulosa or theca cell function is unknown. Therefore, the objective of these studies was to determine the effect of angiogenin on proliferation and steroidogenesis of bovine granulosa and theca cells. In experiments 1 and 2, granulosa cells from small (1 to 5 mm diameter) follicles and theca cells from large (8 to 22 mm diameter) follicles were cultured to evaluate the dose-response effect of recombinant human angiogenin on steroidogenesis. At 30 and 100 ng/ml, angiogenin inhibited (P<0.05) granulosa cell progesterone production and theca cell androstenedione production but did not affect (P>0.10) granulosa cell estradiol production or theca cell progesterone production, and did not affect numbers of granulosa or theca cells. In experiments 3 and 4, granulosa and theca cells from both small and large follicles were cultured with 300 ng/ml of angiogenin to determine if size of follicle influenced responses to angiogenin. At 300 ng/ml, angiogenin increased large follicle granulosa cell proliferation but decreased small follicle granulosa cell progesterone and estradiol production and large follicle theca cell progesterone production. In experiments 5 and 6, angiogenin stimulated (P<0.05) proliferation and DNA synthesis in large follicle granulosa cells. In experiment 7, 300 ng/ml of angiogenin increased (P<0.05) CYP19A1 messenger RNA (mRNA) abundance in granulosa cells but did not affect CYP11A1 mRNA abundance in granulosa or theca cells and did not affect CYP17A1 mRNA abundance in theca cells. We conclude that angiogenin appears to target both granulosa and theca cells in cattle, but additional research is needed to further understand the mechanism of action of angiogenin in granulosa and theca cells, as well as its precise role in folliculogenesis. 相似文献
40.
We have tested the effect of alkaloids (cocaine, morphine) and enkephalins on neutral endopeptidase of peripheral blood mononuclear cells activated by lectins. When treated with concanavalin A and cocaine, peripheral blood mononuclear cells showed an enhanced activity (+110 per cent) of the membrane neutral endopeptidase, which was not related to the expression of the common acute lymphoblastic leukemia antigen at the cell surface, although both molecules have the identical amino acid sequence. Phytohemagglutinin-P, morphine and synthetic enkephalins did not induce the activity of neutral endopeptidase nor the expression of common acute lymphoblastic leukemia antigen. Our findings suggested that the drugs of abuse, cocaine and morphine, affected specific membrane constituents without altering proliferation, subcellular localization of membrane enzymes or the surface immune phenotype of peripheral blood mononuclear cells. 相似文献