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1.
Myeloid-derived suppressor cells (MDSCs) play a crucial role in T cell dysfunction, which is related to poor outcome in patients with severe trauma. Cyclooxygenase-2 (Cox-2) contributes to immune disorder in trauma and infection via production of prostaglandin E2. However, the role of Cox-2 in the accumulation and function of MDSCs after traumatic stress has not been fully elucidated. In the present study, we treated murine trauma model with NS398, a selective Cox-2 inhibitor. Then the percentages of CD1 lb+/Gr-l+ cells, proliferation and apoptosis of CD4+ T cells were determined. Ar- ginase activity and arginase-1 (Arg-1) protein expression of splenic CDllb+/Gr-I+ cells, and de- layed-type hypersensitivity (DTH) response were analyzed. The results showed that Cox-2 blockade significantly decreased the percentages of CD1 lb+/Gr-l+ cells in the spleen and bone marrow 48 and 72 h after traumatic stress. NS398 inhibited arginase activity and down-regulated the Arg-1 expression of splenic CD1 lb+/Gr-l+ ceils. Moreover, NS398 could promote proliferation and inhibit apoptosis of CD4+ T cells. It also restored DTH response of traumatic mice. Taken together, our data revealed that Cox-2 might play a pivotal role in the accumulation and function of MDSC after traumatic stress.  相似文献   

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Objective Conflicting data have been generated from previous studies to determine which kind of relationship exists between HIV-1 specific CD8 Tcell responses and HIV-1 viral load or CD4 count over the course of infection.In this study,153 HIV-1 infected LTNPs were enrolled to investigate the role of HIV-1 specific CD8 T-cell responses in chronic HIV-1 infection among HIV-1 infected former blood donors.Methods The patients were stratified into three groups according to CD4 count:CD4≥500 cells/μL;350 cells/μL≤CD4〈500 cells/μL;CD4〈350 cells/μL.PBMCs were isolated from the patients' anticoagulated blood samples.IL-2 and IFN-γ secretions of CD 8 T cells against 17 HIV-1 consensus B full peptide pools were analyzed by using ICS assay.Results An overall inverse correlation were observed between CD4 count and plasma viral load.Although no significant difference was observed during the comparisons of frequency/breadth of HIV-1 specific CD8 T cell responses,CD4 count stratification analysis showed that different correlation pattern existed in three strata:as for patients whose CD4 counts were less than 350 cells/μL,no significant correlations were identified between frequency/breadth of HIV-1 specific CD8 T cell responses and CD4 count/viral load;as for patients whose CD4 counts ranged from 350 cells /μL to 500 cells/μL,significant correlation was only observed between the response breadth of IL-2+IFN-γ+ CD8 T cells and CD4 count;however,as for patients whose CD4 counts were more than 500 cells/μL,direct correlations were identified between IL-2+IFN-γ+/IL-2+/IFN-γ+ CD8 T cells and viral load or CD4 count.Conclusions Universal consistent inverse correlation was only indentified between CD4 count and viral load.The relationship between HIV-1 specific CD8 T cell responses and CD4 count/viral load varied in different CD4 strata,which showed that better preserved CD4 T cells were correlated with better CD8 T cell functions.  相似文献   

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Background Cervical spondylotic myelopathy (CSM) is a common cause of disability in elderly patients.Previous studies have shown that spinal cord cell apoptosis due to spinal cord compression plays an important role in the pathology of myelopathy.Although changes in magnetic resonance imaging (MRI) T2 signal intensity ratio (SIR) are considered to be an indicator of CSM,little information is published supporting the correlation between changes in MRI signal and pathological changes.This study aims to testify the correlation between MRI T2 SIR changes and cell apoptosis using a CSM animal model.Methods Forty-eight rabbits were randomly assigned to four groups:one control group and three experimental chronic compression groups,with each group containing 12 animals.Chronic compression of the cervical spinal cord was implemented in the experimental groups by implanting a screw in the C3 vertebra.The control group underwent sham surgery.Experimental groups were observed for 3,6,or 9 months after surgery.MRI T2-weighted SIR Tarlov motor scores and cortical somatosensory-evoked potentials (CSEPs) were periodically monitored.At each time point,rabbits from one group were sacrificed to determine the level of apoptosis by histology (n=6) and Western blotting (n=6).Results Tarlov motor scores in the compression groups were lower at all time points than the control group scores,with the lowest score at 9 months (P <0.001).Electrophysiological testing showed a significantly prolonged latency in CSEP in the compression groups compared with the control group.All rabbits in the compression groups showed higher MRI T2 SIR in the injury epicenter compared with controls,and higher SIR was also found at 9 months compared with 3 or 6 months.Histological analysis showed significant apoptosis in the spinal cord tissue in the compression groups,but not in the control group.There were significant differences in apoptosis degree over time (P <0.001),with the 9-month group displaying the most severe spinal cord apoptosis.Spearman's rank correlation test showed that there was close relation between MRI SIR and degree of caspase-3 expression in Western blotting (r=0.824.P <0.001).Conclusions Clear apoptosis of spinal cord tissue was observed during chronic focal spinal compression.Changes in MRI T2 SIR mav be related to the severity of the apoptosis in cervical spinal cord.  相似文献   

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Allergic asthma has been defined as a disease of immunodysregulation, where the pathology is a direct consequence of excessive T-helper type 2 immune responses (Th2) to allergens in the lungs. Disease is associated with increased secretion of type-2 cytokines such as interleukin (IL)-4, IL-5 and IL-13 which, among other things,  相似文献   

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This study aimed to investigate inflammatory edema after cerebral ischemia through 7.0T MRI and proton magnetic resonance spectroscopy(MRS). All SD rats were randomly divided into sham operated group and middle cerebral artery occlusion(MCAO)-1 day,-3 day and-7 day groups. MRI scan of the brain was performed on a 7.0 Tesla MRI scanner. The volume of positive signals in the ischemic side was detected by using a T2 weighted spinecho multislice sequence; the changes in the height of water-peak were measured with point resolved spectroscopy(PRESS) sequences; cortical edema was detected by using wet-dry weight method; the degrees of nerve injury were evaluated by Bederson neurological score system; double-labeling immunofluorescence technique was used to explore the molecular mechanisms of post-ischemia cerebral edema. The results showed that high T2WI signals were observed in MCAO-1 day,-3 day and-7 day groups, and the water-peak height and water-peak area of MCAO groups were higher than those of sham operated group(P0.05). Neurological score results were consistent with the degree of brain edema, and a large number of microglia accumulated in the ischemic cortex. Our results suggested that non-invasive MRI technology with the advantage of high spatial resolution and tissue resolution can comprehensively and dynamically observe inflammatory edema after cerebral ischemia from a three-dimensional space, and contribute to evaluation and treatments in clinic.  相似文献   

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Background Sweat glands (SGs) can not regenerate after complete destruction in the severe skin injury,so it is important to find a ideal stem cell source in order to regenerate functional SGs.Hair foll...  相似文献   

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Dioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin against human LNCaP cells, and evaluated the possible mechanism involved in its antineoplastic action. It was found that dioscin(1, 2 and 4 μmol/L) could significantly inhibit the viability of LNCaP cells in a time- and concentration-dependent manner. Flow cytometry revealed that the apoptosis rate was increased after treatment of LNCaP cells with dioscin for 24 h, indicating that apoptosis was an important mechanism by which dioscin inhibited cancer. Western blotting was employed to detect the expression of caspase-3, Bcl-2 and Bax in LNCaP cells. The expression of cleaved caspase-3 was significantly increased, and meanwhile procaspase-3 was markedly decreased. The expression of anti-apoptotic protein Bcl-2 was down-regulated, whereas the pro-apoptotic protein Bax was up-regulated. Moreover, the Bcl-2/Bax ratio was drastically decreased. These results suggested that dioscin possessed potential anti-tumor activity in human LNCaP cells through the apoptosis pathway, which might be associated with caspase-3 and Bcl-2 protein family.  相似文献   

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OBJECTIVE: Oleanolic acid (OA) has been reported to have anticancer effects, but the extent of its cytotoxicity, its ability to interact with nuclear DNA, its action against skin melanoma, as well as the molecular mechanism of its action against cell proliferation and in support of cell death are still unexplored. This led us to examine the efficacy of OA, a bioactive compound isolated from Phytolacca decandra, on these issues in the present investigation. METHODS: Studies related to analyses of cell viability, drug-DNA interaction, cell proliferation, cell cycle and epidermal growth factor receptor (EGFR) activity were performed. To investigate whether cells undergo apoptosis, studies like fluorescence microscopy, poly (ADP-ribose) polymerase (PARP) degradation, annexin V-fluorescein isothiocyanate/propidium iodide assay, alteration in mitochondrial membrane potential and activity of some relevant signaling proteins were performed. RESULTS: OA displayed a minimal and negligible cytotoxic effect on normal HaCaT cells (skin keratinocytes) and peripheral blood mononuclear cells but by contrast it reduced A375 cell viability significantly. OA interacted with nuclear DNA quickly after exposure. It acted as an anti- proliferative agent. It suppressed EGFR activity. OA administration led the cells to mitochondria- dependent caspase 3-mediated apoptosis. CONCLUSION: OA interacts with cellular DNA, inhibits proliferation possibly through modulating EGFR activity and induces mitochondria-dependent caspase 3-mediated apoptosis in A375 cells which would qualify it as a potent anticancer agent.  相似文献   

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Background Many researches demonstrate that the secondary brain injury which is caused by autoimmune attack toward brain antigens plays an important role in surgical brain injury (SBI).Although traditional immunosuppression can reduce autoimmune attack,it will lower the body immunity.Immune tolerance,by contrast,not only does not lower the body immunity,but also could lighten autoimmunity.This study used thymus tolerance to develop an immune system that is tolerant to autologous cerebrospinal fluid (CSF) and autologous brain tissue so that autoimmune injury can be suppressed following the disruption of the blood-brain barrier,thereby reducing brain damage.Methods Eighty experimental rabbits were divided into five groups by random number table method:16 in SBI group (group A),16 in SBI+CSF drainage group (group B),16 in SBI+CSF drainage+PBS injection group (group C),16 in SBI+CSF drainage+CSF intrathymic injection group (group D),and 16 in SBl+brain homogenate intrathymic injection group (group E).Rabbits' CSF was drained in group B; was drained and injected PBS into thymus in group C; was drained and injected CSF into thymus in group D; and was injected brain homogenate in group E.Half of the rabbits in each group were phlebotomized on 1st,3rd,7th,and 14th days to observe the changes in IL-I,TGF-β by ELISA test,and CD4CD25 regulatory T cells ratio by flow cytometry,and in other animals brain tissues were taken on 7th day for exploring FasL expression by RT-PCR.The least significant difference (LSD) test was used to make paired comparisons; P <0.05 was considered statistically significant.Results The levels of FasL,TGF-β,and the ratios of CD4CD25 regulatory T cells in groups D and E were apparently higher than those in other three groups (P <0.05).Likewise,the levels of IL-1 in these two groups were lower than the other three groups (P <0.05).Moreover,the ratios of CD4CD25 regulatory T cells and the levels of TGF-β in groups B and C were higher than those in group A,but the level of IL-1 was lower than that in group A (P <0.05).There was no significant difference between groups B and C,and groups D and E.Conclusion Thymic injection of CSF and brain homogenate may be able to reduce inflammation after SBI,so thymus immune tolerance may be a useful therapy to treat SBI.  相似文献   

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Summary: The deubiquitinating enzyme ubiquitin specific peptidase 15 (USP15) is regarded as a regulator of TGFβ signaling pathway. This process depends on Smad7, the inhibitory factor of the TGFβ signal, and type Ⅰ TGFβ receptor (TβR- Ⅰ ), one of the receptors of TGFβ. The expression level of USP 15 seems to play vital roles in the pathogenesis of many neoplasms, but so far there has been no report about USP15 in psoriasis. In this study, immunohistochemical staining of USP15, TβR- Ⅰ and Smad7 was performed in 30 paraffin-embedded psoriasis specimens and 10 normal specimens to investigate the expression of USP15, TβR- Ⅰ and Smad7 in psoriasis and to explore the relevance among them. And USP 15 small interfering RNA (USP 15 siRNA) was used to transfect Hacat cells to detect the mRNA expression of TβR- Ⅰ and Smad7. Of 30 cases of psoriasis in active stage, 28, 24 and 26 cases were positive for USP15, TβR- Ⅰ and Smad7 staining, respectively. The positive rates of USP15 and Smad7 were significantly higher in psoriasis specimens than in normal skin specimens (44.1%±26.0% vs. 6.1%±6.6%, 47.2%±27.1% vs. 6.6%±7.1%), and positive rate of TβR- I (20.3%±22.2%) in psoriasis was lower than that in normal skin specimens (46.7%±18.2%). There was a significant positive correlation between USP15 and Smad7 expression, and significant negative correlations between USP15 and TβR- Ⅰ expression, and between TβR- Ⅰ and Smad7 expression in psoriasis. After transfection of USP15 siRNA in Hacat ceils, the expression ofTβR- Ⅰ mRNA was up-regulated and that of Smad7 was down-regulated. It is concluded that USP15 may play a role in the pathogenesis of psoriasis through regulating the TβR- Ⅰ/Smad7 pathway and there may be other cell signaling pathways interacting with USP 15 to take part in the development of psoriasis.  相似文献   

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BACKGROUND: Rheumatoid arthritis (RA), as a common systemic inflammatory autoimmune disease, affects approximately 1 in 100 individuals. Effective treatment for RA is not yet available because current research does not have a clear understanding of the etiology and pathogenesis of RA. Xinfeng Capsule, a patent Chinese herbal medicine, has been used in the treatment of RA in recent years. Despite its reported clinical efficacy, there are no large-sample, multicenter, randomized trials that support the use of Xinfeng Capsule for RA. Therefore, we designed a randomized, double-blind, multicenter, placebo-controlled trial to assess the efficacy and safety of Xinfeng Capsule in the treatment of RA. METHODS AND DESIGN: This is a 12-week, randomized, placebo-controlled, double-blind, multicenter trial on the treatment of RA. The participants will be randomly assigned to the experimental group and the control group at a ratio of 1:1. Participants in the experimental group will receive Xinfeng Capsule and a pharmaceutical placebo (imitation leflunomide). The control group will receive leflunomide and an herbal placebo (imitation Xinfeng Capsule). The American College of Rheumatology (ACR) Criteria for RA will be used to measure the efficacy of the Xinfeng Capsule. The primary outcome measure will be the percentage of study participants who achieve an ACR 20% response rate (ACR20), which will be measured every 4 weeks after randomization. Secondary outcomes will include the ACR50 and ACR70 responses, the side effects of the medications, the Disease Activity Score 28, RA biomarkers, quality of life, and X-rays of the hands and wrists. The first four of the secondary outcomes will be measured every 4 weeks and the others will be measured at baseline and after 12 weeks of treatment. DISCUSSION: The result of this trial will help to evaluate whether Xinfeng Capsule is effective and safe in the treatment of RA. TRIAL REGISTRATION: This trial has been registered in ClinicalTrials.gov. The identifier is N CT01774877.  相似文献   

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Undifferentiated carcinoma with osteoclast-like giant cells, also formerly known as osteoclast-like giant cell tumor, is a rare neoplasm of the pancreas and usually diagnosed after pancreatectomy. The presence of non-neoplastic osteoclast-like giant cells is the histological hallmark of this tumor and the diagnosis is usually not difficult on tissue sections. However there have been relatively few reports regarding the cytological features of this type of tumor in literatures. Here we present a case of undifferentiated pancreatic carcinoma with osteoclast-like giant cells coexisting with ductal adenocarcinoma diagnosed by endoscopic ultrasonography (EUS)-guided fine-needle aspiration (FNA) and liquid-based cytology test. To our knowledge,  相似文献   

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Background Transient sublethal ischemia is known as ischemic preconditioning, which enables cells and tissues to survive subsequent prolonged lethal ischemic injury. Ischemic preconditioning exerts neuroprotection through phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Cbl-b belongs to the Casitas B-lineage lymphoma (Cbl) family, and it can regulate the cell signal transduction.The roles of ubiquitin ligase Cbl-b and PI3K/Akt pathway and the relationship between them in oxygen-glucose deprivation preconditioninq (OGDPC) in PC12 cells were investiaated in the ore.~e.nt study  相似文献   

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Artemisinin, also termed qinghaosu, is extracted from the traditional Chinese medicine ar- temesia annua L. (the blue-green herb) in the early 1970s, which has been confirmed for effectively treating malaria, Additionally, emerging data prove that artemisinin exhibits anti-cancer effects against many types of cancers such as leukemia, melanoma, etc. Artemisinin becomes cytotoxic in the presence of ferrous iron. Since iron influx is high in cancer cells, artemisinin and its analogs selectively kill can- cer cells with increased intracellular iron concentrations. This study is aimed to investigate the selective inhibitory effects of artemisinin on SMMC-7721 cells in vitro and determine the effect of holotransfer- fin, which increases the concentration of ferrous iron in cancer cells, combined with artemisinin on the anticancer activity. MTT assay was used for assessing the proliferation of SMMC-7721 cells treated with artemisinin. The induction of apoptosis and inhibition of colony formation in SMMC-7721 cells treated with artemisinin were determined by TdT-mediated dUTP nick end labeling (TUNEL) and col- ony formation assay, respectively. The results showed that artemisinin at various concentrations signifi- cantly inhibited growth, colony formation and cell viability of SMMC-7721 cells (P〈0.05), likely due to induction of apoptosis of SMMC-7721 cells. Of interest, it was found that incubation of artemisinin combined with holotransferrin sensitized the growth inhibitory effect of artemisinin on SMMC-7721 cells (P〈0.01). Our data suggest that treatment with artemisinin leads to inhibition of viability and pro- liferation, and apoptosis of SMMC-7721 ceils. Furthermore, we observed that holotransferrin signifi- cantly enhanced the anti-cancer activity of artemisinin. This study may provide a potential therapeutic choice for liver cancer.  相似文献   

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The effects of granulocyte colony-stimulation-factor (G-CSF) on stem cell mobilization and its impact on the amplification of myeloid-derived suppressor cells (MDSCs) of donor mice were ex- amined. A mouse model of stem cell mobilization was established by consecutive subcutaneous injec- tion of 100 μg/kg G-CSF for 5 days. The blood from the donor mice was routinely examined during mobilization. Stem cells and MDSCs were analyzed by flow cytometry. The immunosuppressive mole- cules derived from MDSCs in serum and spleen, including hydrogen dioxide (H202) and nitric oxide (NO), and the activity of nitric oxide synthase (NOS) were determined during the mobilization. Apop- tosis of T lymphocytes was assessed by using Annexin-V/PI. During stem cell mobilization, the number of lymphocytes and white blood cells in the peripheral blood was increased, and peaked on the 4th day. The number of stem cells in G-CSF-treated mice was significantly greater than that in controls (P〈0.01). The expansions of MSDCs were also observed after G-CSF mobilization, with a more notable rate of growth in the peripheral blood than in the spleen. The activity of NOS and the production of NO were increased in the donor mice, and the serum H202 levels were approximately 4-fold greater than the con- trois. Consequently, apoptosis of T lymphocytes was increased and showed a positive correlation with the elevated percentage of MDSCs. It was concluded that G-CSF could provide sufficient peripheral blood stem cells for transplantation. Exogenous administration of G-CSF caused the accumulation of MDSCs in the peripheral blood and the spleen, which could lead to apoptosis ofT lymphocytes and may offer a new strategy for the prevention and treatment of graft versus host disease.  相似文献   

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