Objective To study the effects of adenosine 2A receptor activation on activation, proliferation, and toxicity of T lymphocytes stimulated by phytohemagglutinin (PHA) in vitro. Methods A model of activated T cells was established by stimulating the cells with PHA. Those T cells were treated with different concentrations of adenosine 2A receptors agonist (0.01 μmol/L, 0.1 μmol/L, 1 μmol/L, and 10 μmol/L CGS21680). The expressions of CD69, CD25 and proliferation of T cells were measured by fluorescent antibody stain and flow cytometry. ELISA method was used to detect IL-2 and INF-γ levels. Results All concentrations of CGS21680 significantly inhibited the expressions of CD25 and CD69 on PHA-stimulated T cells surface and proliferation of T cells (Plt;0.05, Plt;0.01). IL-2 and INF-γ secreted by T cells were significantly suppressed, too (Plt;0.01). Conclusion Activation of adenosine 2A receptor can effectively inhibit the activation, proliferation, and toxicity of T cells in vitro.
Calnexin is a lectin-like molecular chaperone protein on the endoplasmic reticulum, mediating unfolded protein responses, the endoplasmic reticulum Ca2+ homeostasis, and Ca2+ signals conduction. In recent years, studies have found that calnexin plays a key role in the heart diseases. This study aims to explore the role of calnexin in the activation of cardiac fibroblasts. A transverse aortic constriction (TAC) mouse model was established to observe the activation of cardiac fibroblasts in vivo, and the in vitro cardiac fibroblasts activation model was established by transforming growth factor β1 (TGFβ1) stimulation. The adenovirus was respectively used to gene overexpression and silencing calnexin in cardiac fibroblasts to elucidate the relationship between calnexin and cardiac fibroblasts activation, as well as the possible underlying mechanism. We confirmed the establishment of TAC model by echocardiography, hematoxylin-eosin, Masson, and Sirius red staining, and detecting the expression of cardiac fibrosis markers in cardiac tissues. After TGFβ1 stimulation, markers of the activation of cardiac fibroblast, and proliferation and migration of cardiac fibroblast were detected by quantitative PCR, Western blot, EdU assay, and wound healing assay respectively. The results showed that the calnexin expression was reduced in both the TAC mice model and the activated cardiac fibroblasts. The overexpression of calnexin relieved cardiac fibroblasts activation, in contrast, the silencing of calnexin promoted cardiac fibroblasts activation. Furthermore, we found that the endoplasmic reticulum stress was activated during cardiac fibroblasts activation, and endoplasmic reticulum stress was relieved after overexpression of calnexin. Conversely, after the silencing of calnexin, endoplasmic reticulum stress was further aggravated, accompanying with the activation of cardiac fibroblasts. Our data suggest that the overexpression of calnexin may prevent cardiac fibroblasts against activation by alleviating endoplasmic reticulum stress.
Objective To further strengthen the understanding of the genesis of thyroid tumors through the analysis of thyroid nodules in the clonal origin. Method The related literatures which discussed the clonality of thyroid nodules were reviewed and analyzed. Results About the clonal origin of thyroid nodules, the X chromosome inactivation detection and single gene mutation detection were the most widely chosen one at present. Most of the materials available at present related to X chromosome inactivation proposed that major part of the thyroid nodules were monoclonal and the malignant cells spreaded by means of the inner lymphatic vessel net,whereas polyclonal and monoclonal thyroid nodules coexisted occasionally. Only BRAF mutation was found of certain importance in clonal origin identification in the thyroid nodules. Conclusions Thyroid nodule is prevalent in clinical practice,while the clonality of thyroid nodules especially the thyroid tumor is not clear. And for the time being the commonly used methods to identify the clonal origin of thyroid nodule are X chromosome inactivation and single gene mutation detection. Published results confirm the finding of X chromosome inactivation methods that the majority of thyroid nodules are monoclonally originated.
Objective To verify the technics of inactivating/removing pathogens in medical chitosan derived from shrimp shell. Methods Possible pathogen species were included according to the raw material of shrimp shell used in production, then bacillus cereus, porcine parvovirus (PPV) and pseudorabies virus (PRV) were selected as indicator pathogens.Pathogen solution was prepared in accordance with Technical Standard for Disinfection. The processing procedure of medical chitosan was analyzed to determine whether the alkal ization of chitin and the filter steril ization of chitosan were capable of inactivating/removing pathogens and their efficiencies were tested. Results Bacillus cereus was removed by 8 184 cfu/ mL after alkal ization and 30 818 cfu/mL after filter steril ization. The average logarithm inactivation value (LIV) of PPV and PRV after alkal ization were equal to or above 4.76 logTCID50/0.1 mL and 6.67 logTCID50/0.1 mL, respectively, and their average LIV after filter steril ization were 2.25 logTCID50/0.1 mL and 3.04 logTCID50/0.1 mL. The alkal ization of chitin inactivated/removed indicator pathogens effectively, while the filter steril ization of chitosan removed bacterial effectually but could not inactivate viruses completely. Conclusion The alkal ization of chitin can be used as the technics of inactivating/removing pathogens during the preparation process of medical chitosan to guarantee the safety of the product.
【Abstract】 Objective To discuss the role of leukocyte activation and inflammatory processes in the disease of chronic venous insufficiency (CVI). Methods The relevant literatures about the role of leukocyte activation and inflammatory reaction in CVI were reviewed. Results The role of inflammatory reaction in occurrence and development of venous diseases has been studied a lot in recent years. It was found that the leukocyte activation and inflammatory reaction are involved in the structural remodeling of venous valves and walls, leading to valvular incompetence and formation of varicose veins. Conclusion Leukocyte activation and inflammatory processes take important roles in the occurrence and progression of CVI.
Objective To investigate the role and mechanism of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) in the activation of aortic valve interstitial cells (AVICs) in aortic stenosis. Methods Isolating primary AVICs and stimulating their activation with transforming growth factor β1 (TGF-β1, 30 ng/mL), the expression of PGC-1α was detected. The activation of AVICs induced by TGF-β1 was observed after overexpression of PGC-1α by adenovirus or inhibition of PGC-1α function by GW9662. The possible downstream molecular mechanism of PGC-1α in AVICs activation was screened. Finally, the phenotype was further verified in primary human AVICs. Results The expression of PGC-1α decreased after the activation of AVICs induced by TGF-β1 (control group: 1.00±0.18; 24 h: 0.31±0.10; 48 h: 0.32±0.06; 72 h: 0.20±0.07; P<0.05). Specific overexpression of PGC-1α by adenovirus inhibited the activation of AVICs induced by TGF-β1 stimulation (periostin: 3.17±0.64 vs. 1.45±0.54, P<0.05; α-smooth muscle actin: 0.77±0.11 vs. 0.28±0.06, P<0.05). On the contrary, inhibition of PGC-1α function by GW9662 promoted the activation of AVICs (periostin: 2.20±0.68 vs. 7.99±2.50, P<0.05). Subsequently, it was found that PGC-1α might inhibit the activation of AVICs through downregulating the expression of calcium/calmodulin-dependent protein kinase (CAMK1δ) (0.97±0.04 vs. 0.74±0.11, P<0.05), and downregulating the expression of CAMK1δ alleviated the activation of AVICs (periostin: 1.76±0.11 vs. 0.99±0.20, P<0.05). The possible mechanism was that the activation of mammalian target of rapamycin (mTOR) signaling pathway was inhibited by reducing the accumulation of reactive oxygen species (ROS) (778.3±139.4 vs. 159.3±43.2, P<0.05). Finally, the protective effect of PGC-1α overexpression was verified in the activated phenotype of human AVICs (periostin: 2.73±0.53 vs. 1.63±0.14, P<0.05; connective tissue growth factor: 1.27±0.04 vs. 0.48±0.09, P<0.05). Conclusions The expression of PGC-1α significantly decreases during the activation of AVICs induced by TGF-β1. The overexpression of PGC-1α significantly inhibites the activation of AVICs, suggesting that PGC-1α plays a protective role in the activation of AVICs. The possible mechanism is that PGC-1α can inhibit the activation of CAMK1δ-ROS-mTOR pathway. In conclusion, interventions based on PGC-1α expression levels are new potential therapeutic targets for aortic stenosis.
Rheumatoid arthritis (RA) is a chronic autoimmune disease remarkably characterized by synovitis of joints, whose pathogenesis is complicated and not yet fully elucidated. A variety of cells, cytokines and intercellular signaling pathways are involved in the occurrence and development of RA. The mitogen activation protein kinase (MAPK) signaling pathway is closely related to the pathogenesis of RA, and plays an important role in the formation of pannus, synovitis, and bone destruction. This paper reviews the research progress of MAPK signaling pathway in RA from the aspects of the interaction of MAPK signaling pathway with a variety of key cells and cytokines in the pathogenesis of RA, in order to provide a direction and theoretical basis for anti-RA drug therapy research.
Objective To introduce the basic information about mad cow disease and the current status of safety control of medical devices derived from mammalian animal tissues. Methods Literature concernedwas reviewed intensively. Results Mad cow disease, also knownas bovine spongiform encephacitis (BSE), is generally considered from the samesource of Scrapie, and they are caused by the same kind of sponginess brain tissue pathological changes. Mad cow disease is caused by the misfolding of a small protein called Prion. This disease has the character of slowly breaking down the central neuron system of animals. Conclusion Further researches can provide evaluation for safety considerations of medical devices deriving from animal.
【Abstract】Objective To investigate the production and possible significance of plasma trypsinogen activation peptides (TAP) in rat experimental acute pancreatitis. Methods Ninety SD rats were randomly allocated to five groups: group EP with retrograde ductal infusion of 3%sodium taurocholate; group NP with retrograde ductal infusion of 5%sodium taurocholate; group TP with retrograde ductal infusion of 3%sodium taurocholate and ulinastatin(UTI) intravenous infusion half an hour later; group CP with 0.9% NS retrograde ductal infusion; group OP with sham operation. Animals in each group were killed 3h,6h and 24h after infusion. Plasma TAP was determined by EIA.The histological severity of the pancreas were assessed by Schmidt method. Results The pancreatic pathological changes in group NP was significantly severe than in group EP. At 3h and 6h after infusion, plasma TAP concentration of group NP (4.798±0.169)nmol/L and (3.999±0.299)nmol/L were significant higher than that of group EP(2.416±0.148)nmol/L and (3.356±0.211)nmol/L. At 6h after infusion plasma TAP concentration of group TP 〔(1.611±0.113)nmol/L〕 was significant lower than that of group EP(3.356±0.211)nmol/L. The difference of plasma TAP concentration between group EP and group NP appeared prior to the difference of the histopathological changes of pancreas between two groups. Conclusion Plasma TAP concentration is connected with the severity of sodium taurocholate-induced rat pancreatitis. Plasma TAP concentration may be used as a marker for early assessment of the severity of this experimental acute pancreatitis.
ObjectiveTo observe the effect of complement receptor 1 (CR1) on barrier of cultured human retinal epithelial cells (hRPE) under complement-activated oxidative stress. MethodsThe third to fifth passage of hRPE cultured on Transwell insert were used to establish a stable hRPE monolayer barrier. The hRPE monolayer barrier was exposed to 500 μmol/L ten-butyl hydroperoxide and 10% normal human serum to establish the hRPE monolayer barrier model of complement-activated oxidative stress in vitro. hRPE monolayer barriers under complement-activated oxidative stress were divided into two groups including model group and CR1 treatment (1 μg/ml) group. Model group and CR1 treatment group were treated with 1 μl phosphate buffer solution (PBS) or CR1 for 4 hours. Normal hRPE monolayer barrier were used as control in transepithelial resistance (TER) measurement experiment. TER was measured to evaluate the barrier function of hRPE. The hRPE-secreted vascular endothelial growth factor (VEGF) and chemokine (C-C Motif) Ligand 2 (CCL2), together with complement bioactive fragments (C3a, C5a) and membrane-attack complex (MAC) in the supernatant were detected by enzyme-linked immune sorbent assay. ResultsStable hRPE monolayer barrier was established 3 weeks after hRPE seeded on Transwell insert. Complement-activated oxidative stress resulted in a sharp decrease of TER to 54.51% compared with normal hRPE barrier. CR1 treatment could significantly improve TER of barrier under complement-activated oxidative stress to 63.48% compared with normal hRPE barrier(t=21.60, P < 0.05). Compared with model group, CR1 treatment could significantly decrease the concentration of VEGF and CCL2 by 11.48% and 23.47% secreted by hRPE under complement-activated oxidative stress (t=3.26, 2.43; P < 0.05). Compared with model group, CR1 treatment could also decreased the concentration of C3a, C5a and MAC by 24.00%, 27.87%, 22.44%.The difference were statistically significant (t=9.86, 2.63, 6.94; P < 0.05). ConclusionsCR1 could protect the barrier function of hRPE cells against complement-activated oxidative stress. The underlying mechanism may involve inhibiting complement activation and down-regulating the expression of VEGF and CCL2.