west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "Protein" 46 results
  • LOCALIZATION OF PROTEIN KINASE C IN RABBIT RETINA

    PURPOSE:To verify existance of a-,~-,and 3'-protein kinase C(PKC)subspecies and their localization in rabbit retina. METHODS: Using an immunohistoehemical technique with mono- elonal antibodies against PKC isozymes- I (a),-I[ (13),and -~[ (Y) to characterize the distribution of PKC in rabbit retina. RESULTS:There is a positive immunostaining for a-,13-,and ~-PKC in rabbit retina. The immunoreactivity of a-PKC was observed mainly in the bipolar cells of inner nuclear layer and the outer segments of photorecptors. The positive immunostaining of 13-PKC could be seen in the ganglion cells,inner plexiform layer,inner nuclear layer,and the outer segments of photoreceptors. A diffuse and weak staining of Y-PKC is recognized in the ganglion cell layer,inner plexifrom layer,inner nuclear layer, and the outer segments of photoreceptors. CONCLUSION:The protein kinase C sub- speeies-a,-~,and-'Y are present in retina which is a part of the central nervous system

    Release date:2016-09-02 06:21 Export PDF Favorites Scan
  • Effect of high glucose on the expression of activating transcription factor 4 in cultured retinal Müller glia cells

    Objective To observe the effect of high glucose on the expression of activating transcription factor 4 (ATF4) in cultured retinal Muuml;ller glia cells. Methods The retinal tissue of Sprague-Dawley (SD) rats was collected, and Muuml;ller cells were isolated and cultured. The glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS) of Muuml;ller cells were identified by streptavidin-biotin-peroxidase complex. Cultured rat Muuml;ller cells were divided into control group (5.5 mmol/L glucose), group A (20 mmol/L glucose), group B (30 mmol/L glucose) and group C (40 mmol/L glucose). ATF4 protein expressions in Muuml;ller cells of four groups were measured by Western blot four days after cultured. Results GFAP and GS expressed in more than 95% of Muuml;ller cells. Over 95% of Muuml;ller cells of group A, B and C were positive for GFAP and GS. Western blots indicated that ATF4 protein in group A, B and C increased obviously compared with the control group (q=0.293, 0.754,0.484;P<0.05). Conclusion High glucose can increase the expression of ATF4 protein and cause endoplasmic reticulum stress in retinal Muuml;ller glia cells in vitro.

    Release date:2016-09-02 05:26 Export PDF Favorites Scan
  • Research progress on the mechanism and treatment of endoplasmic reticulum stress in diabetic retinopathy

    Diabetic retinopathy (DR), a neurovascular complication of diabetes, presents a multifaceted pathogenesis that encompasses numerous biological processes and molecular mechanisms. Endoplasmic reticulum stress (ERS) plays a critical role in the maintenance of cellular homeostasis, and diabetic neuro-microangiopathy is driven by high glucose, which activated ERS through the promotion of protein misfolding, oxidative stress, and disturbances in calcium homeostasis. ERS activates the unfolded protein response, thereby influencing the onset and progression of DR through modulating mitochondria-associated endoplasmic reticulum membranes, autophagy, apoptosis, microvascular function, oxidative stress, and inflammation pathways. Currently, the principal interventions against ERS comprise the modulation of the ERS signalling axis and its interactions with associated pathological processes such as autophagy, oxidative stress, and inflammation, through pharmacological and molecular mechanisms. These interventions are directly or indirectly shown to inhibit persistent ERS and are demonstrated to ameliorate DR. With the in-depth study of ERS and the research and development of various drugs for ERS, it is expected to bring novel insights and strategies for DR management in the future.

    Release date:2025-01-21 10:27 Export PDF Favorites Scan
  • Effect of internal jugular vein bypass Rex surgery on anticoagulant factors and portal pressure in children with extrahepatic portal vein obstruction

    ObjectiveTo investigate the effect of Rex surgery (superior mesenteric vein-left portal vein shunt) with internal jugular vein bypass on the anticoagulant factors and portal pressure in children with extrahepatic portal vein obstruction (EHPVO).MethodsFrom January 2014 to December 2018, children with EHPVO in Xi’an Children’s Hospital were retrospectively analyzed. All children underwent Rex surgery. The anticoagulant factors, blood routine indicators, and portal pressure-related indicators of all children were tested before and 1 year after Rex surgery, and the differences were compared. ResultsA total of 32 children were enrolled, and all children were followed up for 1 year after Rex surgery, and no follow-up was lost. Follow-up ultrasound examination 1 year after surgery showed that the portal vein blood flow in all children was unobstructed, and there was no venous thrombosis. The concentration of protein C, protein S and antithrombin Ⅲ activity of the children 1 year after surgery [(5.91±0.67) μg/mL, (2.43±0.34) μg/mL and (59.64±4.54)%, respectively] were all higher than those before surgery [(3.25±0.82) μg/mL, (2.02±0.37) μg/mL and (50.22±3.91)%, respectively], and the differences were statistically significant (P<0.05). There was no statistically significant difference in the concentration of antithrombin Ⅲ 1 year after surgery compared with that before surgery (P>0.05). The red blood cell count, hemoglobin concentration, white blood cell count and platelet count of the children 1 year after surgery [(4.61±0.17)×1012/L, (128.53±6.55) g/L, (6.09±0.72)×109/L and (104.88±5.74)×109/L, respectively] were all higher than those before surgery [(3.78±0.19)×1012/L, (105.53±5.31) g/L, (3.39±0.58)×109/L and (87.42±5.53)×109/L, respectively], and the differences were statistically significant (P<0.05). The diameter of the left portal vein 1 year after surgery was larger than that before surgery [(7.23±0.66) vs. (2.30±0.69) mm], the spleen volume was smaller than that before surgery [(55.74±4.07) vs. (67.21±4.22) cm3], and the portal vein pressure was lower than that before surgery [(23.37±1.27) vs. (35.29±1.36) cm H2O (1 cm H2O=0.098 kPa)], and the differences were statistically significant (P<0.05). ConclusionRex surgery with internal jugular vein bypass is beneficial to improving the level of anticoagulant factors in children with EHPVO, improving portal vein blood flow and pressure, and effectively relieving hypersplenism, which has a certain promotion value.

    Release date:2021-10-26 03:34 Export PDF Favorites Scan
  • Expression of liver X receptors and protein phosphatase 1A and their relationship with airway remodeling in bronchial asthma patients

    ObjectiveTo detect the expression of Liver X receptors (LXRs), protein phosphatase 1A (PPM1A), transforming growth factor-β1 (TGF-β1) and Smad2 in peripheral blood of bronchial asthma patients, and to explore whether LXRs and PPM1A are related to airway remodeling.MethodsSubjects were divided into healthy control group, mild and moderate asthma group and severe asthma group, with 30 subjects each. Lung function and high-resolution computed tomography examination were performed on patients with bronchial asthma to define airway remodeling. Peripheral blood was extracted and the serum levels of LXRα, LXRβ, PPM1A, TGF-β1 and Smad2 were detected after centrifugation. Then the data were analyzed.ResultsThe airway remodeling level of the mild and moderate asthma group was significantly higher than that of the control group. The airway remodeling level of the severe asthma group was significantly higher than that of the mild and moderate asthma group. Serum LXRα, LXRβ in asthma group were higher than those in the control group. The levels of LXRα and LXRβ in severe asthma were higher than those in mild and moderate asthma group. There was no significant correlation between LXRs and airway remodeling. The PPM1A level in mild and moderate asthma group was lower than that in the control group. The levels of PPM1A in severe asthma were lower than that in mild and moderate asthma group. PPM1A level was negatively correlated with airway remodeling.ConclusionsThe level of PPM1A in asthma patients is lower than that in healthy subjects, and is negatively correlated with the degree of airway remodeling. Serum LXRs in asthmatic patients are higher than that in healthy subjects, but LXRs are not significantly correlated with airway remodeling.

    Release date:2020-07-24 07:00 Export PDF Favorites Scan
  • The effects and mechanisms of G protein-coupled receptor 91 on blood-retinal barrier in diabetic rats

    ObjectiveTo investigate the effects and mechanisms of G protein-coupled receptor 91 (GPR91) on blood-retinal barrier (BRB) in diabetic rats. MethodsA lentiviral vector of shRNA targeting rat GPR91 and scrambled shRNA were constructed. Healthy male Sprague-Dawley (SD) rats were selected in this study. The 60 rats were randomized into 4 groups and treated as follows:(1) control group (Group A, n=15), the rats received injections of an equal volume of 0.1% citrate buffer; (2) streptozocin (STZ) group (Group B, n=15), the rats received injections of STZ; (3) LV.shScrambled group (Group C, n=15), diabetic rats received an intravitreal injection of 1 μl 1×108 TU/ml scrambled shRNA lentiviral particles at 2 weeks after the induction of diabetes; (4) LV.shGPR91 group (Group D, n=15), diabetic rats received an intravitreal injection of 1 μl 1×108 TU/ml pGCSIL-GFP-shGPR91 lentiviral particles. At 12 weeks after intravitreal injection, immunohistochemistry and Western blot were used to assess the expression of GPR91, p-extracellular signal-regulated kinase(ERK)1/2, t-ERK1/2, p-Jun N-terminal kinase (JNK), t-JNK, p-p38 mitogen-activated protein kinase (MAPK) and t-p38 MAPK. Haematoxylin and eosin (HE) staining and Evans blue dye were used to assess the structure and function of the retinal vessel. Immunohistochemistry enzyme-linked immunosorbent assay (ELISA) was used to test the protein level of VEGF. ResultsImmunohistochemistry staining showed that GPR91 was predominantly localized to the cell bodies of the ganglion cell layer. Western blot showed that GPR91 expression in Group D decreased significantly compared with Group C (F=39.31, P < 0.01). HE staining showed that the retina tissue in Group B and C developed telangiectatic vessels in the inner layer of retina, while the telangiectatic vessels attenuated in Group D. It was also demonstrated in Evans blue dye that the microvascular leakage in Group D decreased by (33.8±4.11)% compared with Group C and there was significant difference (F=30.35, P < 0.05). The results of ELISA showed the VEGF secretion of Group B and C increased compared with Group A and the VEGF expression in Group D was significantly down regulated after silencing GPR91 gene (F=253.15, P < 0.05).The results of Western blot indicated that compared with Group A, the expressions of p-ERK1/2, p-JNK and p-p38 MAPK were significantly upregulated (q=6.38, 2.94, 3.45;P < 0.05). Meanwhile, the activation of ERK1/2 was inhibited by GPR91 shRNA and the difference was statistically significant (F=22.50, P < 0.05). ConclusionsThe intravitreal injection of GPR91 shRNA attenuated the leakage of BRB in diabetic rats. GPR91 regulated the VEGF release and the leakage of BRB possibly through the ERK1/2 signaling pathway.

    Release date: Export PDF Favorites Scan
  • Research progress in research on Bestrophinopathies and mutations in BEST1 gene

    Mutations in the BEST1 gene are associated with a range of retinal diseases collectively referred to as "Best diseases", including Best vitelline macular dystrophy. More than 300 mutations at different sites of the BEST1 gene have been found, which may cause a series of functional disorders such as the mistransport of the calcium-activated anion channel protein-1 protein encoded by it, protein oligomerization defects, and abnormal anion channel activity, leading to different clinical phenotypes. Although it has been established that the BEST1 gene mutation is associated with at least one different type of Best disease, the relationship between the specific gene mutation site and the specific clinical phenotype has not been fully defined. For the time being. Drugs and gene therapy for the Best diseases are still in the basic research stage, which provides a broad development space for future treatment exploration. In the future, when selecting gene therapy in clinical applications, it is necessary to combine the clinical phenotype and molecular diagnosis of patients, and clearly define their mutation types and pathogenic mechanisms in order to achieve better personalized treatment effects.

    Release date:2025-03-17 03:07 Export PDF Favorites Scan
  • Progress of Molecular Targeted Therapy for Thyroid Cancer

    ObjectiveTo review the recent progress of the molecular targeted therapy for thyroid cancer. MethodsThe literatures of molecular etiology for thyroid cancer, mechanism and evaluation of targeted therapy via Medline and CHKD database were reviewed. ResultsSo far, four molecular targeted drugs (Sorafenib, Lenvatinib, Vandetanib, and Cabozantinib) have been approved for treatment of advanced thyroid cancer by FDA. They can mainly improve the patient's progression-free survival. Besides, several new molecular targeted drugs have accomplishedⅠphase or Ⅱ phase clinical trials. These drugs may be new options for treatment of advanced thyroid cancer in the future. ConclusionsMolecular targeted drugs have been the main therapeutic method for advanced thyroid cancer. However, we should invent more effective new drugs and investigate the drug combination to improve the therapeutic effect.

    Release date: Export PDF Favorites Scan
  • Effect of 5,6-dihydrocyclopenta-1, 2-dithiole-3-thione on Müller cells under the high glucose

    Objective To investigate the cellular viability and mitochondrial reactive oxygen species (ROS) production of the Müller cells under high glucose condition, and explore the protection role of the 5,6-dihydrocyclopenta-1, 2-dithiole-3-thione (CPDT) on Müller cells. Methods Müller cells from Sprague Dawley rats were divided into 5 groups randomly, including 25 mmol/L normal glucose group (group A) and 65 mmol/L high glucose group (group B). High glucose group with 45, 60, 70 μmol/L CPDT and cultured them 72 hour was set as group C, D and E. Water soluble tetrazolium salt (WST)-8 was used to measure the cellular viability. Flow cytometry was used to measure the active oxygen and apoptosis index. The expression of nuclear factor erythroid 2-related factor 2 (Nrf2), hemeoxygenase-1 (HO-1), Bcl-2 and Bax protein were measured by Western blot. Results Compared with group A, the WST-8 showed that the viability of Müller cells apparently decreased in group B (t=39.59,P<0.05). Compared with the group B, the viability of Müller cells had changes in group C (t=0.97,P>0.05), but recovered in group D and E (t=−4.17, −7.52;P<0.05). Compared with group A, the FCM showed that the mitochondrial ROS levels was higher in group B (t=−30.99,P<0.05). Compared with group B, the mitochondrial ROS levels were decreased in group D (t=27.68,P<0.05). Compared with group A, Bax, Nrf2 and HO-1 increased (t=–11.03, –63.17, –11.44;P<0.05), while the bcl-2 decreased in group B (t=7.861,P<0.05). Compared with the group B, Nrf2, HO-1 and Bax decreased (t=15.11, 26.59, 6.27;P<0.05), while the bcl-2 increased in group D (t=−6.53,P<0.05). Conclusions Under the high glucose, CPDT may reduce the mitochondrial ROS levels and the expression of Nrf2, HO-1 and Bax protein of Müller cells. It may inhibit apoptosis through activating the Nrf2/HO-1 pathway and balancing of level of Bcl-2 protein and mitochondrial ROS.

    Release date:2017-05-15 12:38 Export PDF Favorites Scan
  • Effect of Proteinuria on Residual Renal Function in Peritoneal Dialysis Patients

    ObjectiveTo observe whether proteinuria is relate to the decline of residual renal function (RRF) in peritoneal dialysis (PD) patients. MethodsThis is a prospective cohort study including 45 PD patients (underwent PD between January 2011 and January 2013) with a 12-month follow-up. All the patients were divided into 2 groups with respect to the initial proteinuria level: massive proteinuria group A (n=20) and non-massive proteinuria group B (n=25) at baseline. We established regression models to do univariate analysis and multivariate analysis of the relationship between the decline of RRF≥50% of baseline and the indices of age, sex, PD-associated peritonitis, baseliner residual glomerular filtration rate (rGFR), initial proteinuria, and use of ACEI/ARB. ResultsThe primary outcome (RRF>50% of baseline) at 12 months was 65% in group A, and 80% in group B (P<0.05). Based both on the results of univariate and multivariate Cox regression analysis, non-massive proteinuria and higher rGFR at baseline were factors to protect RRF from decline (P<0.05). ConclusionThe study demonstrates that massive proteinuria and lower rGFR at baseline may be associated with a rapid decline of RRF in PD patients. Treatment aimed at reducing albuminuria may lead to protect RRF and improve life quality of patients.

    Release date: Export PDF Favorites Scan
5 pages Previous 1 2 3 4 5 Next

Format

Content