PURPOSE: To probe the effect of taurine on lipid peroxidation,surperoxide dismutase(SOD) and glutathione peroxidase(GSH-Px)in retina in vitro. METHODS: The animal eye cups were put into media(divided into four groups:control,model,taurine and beta;-carotene) respectively,and incubated at 37deg;C in a humidified atmosphere of 5% CO2/95% air. After 24h or 48h ,the retinas were taken out from the media and the SOD,GSH-Px ,protein and malondialdehyde(MDA) were examined. RESULTS:Taurine could inhibite lipid peroxidation in retina ,decrease MDA level ,could not protect GSH-Px activity in retina. The effect of taurine on SOD activity in retina was also uncertain. CONCLUSION:Taurine can inhibit lipid peroxidation in retina in vitro,but the mechanism of that has nothing to do with the effect of taurine on SOD activity and GSH-Px activity. （Chin J Ocul Fundus Dis,1996,12: 183-185 ）
In recent years, with the improvement of the sensitivity of examination equipment and the change of people's living environment and diet, the rate of thyroid cancer has risen rapidly, which has increased nearly five folds in 10 years. The pathogenesis, clinical manifestation, biological behavior, treatment and prognosis of thyroid carcinoma of different pathological types are obviously different. Papillary thyroid carcinoma (PTC) can develop at any age, which accounts for about 90% of thyroid cancer. It progresses slowly and has favourable prognosis, but lymph node metastasis appears easily. Whether PTC is accompanied by lymph node metastasis has an important impact on its prognosis and outcome. The Raf murine sarcoma viral oncogene homolog B(BRAF)gene mutation plays a crucial role in PTC lymph node metastasis. Having an in-depth understanding of the specific role and mechanism of BRAF gene mutation in PTC is expected to provide new ideas for diagnosis and treatment of PTC.
【Abstract】Objective To investigate whether SUMO-1 enhances the apoptosis induced by wild-type p53 plasmid transfection in HepG2 cells. Methods The HepG2 cells were transfected respectively or simultaneouly with the following expressional plasmids as pcDNA3-wtp53（pwtp53，including human wild-type p53 gene），pCMV-HDM1B（pMDM2，including HDM2 gene， homologous gene as murine double minute gene 2），pcDNA3-His6-SUMO-1（pSUMO-1 ，including small ubiquitin-like modifier1 gene）and plasmid pcDNA3.The proteins expressed in cells were detected by means of Western blotting and the apoptosis rates of cells were measured by flow cytometry. Results The protein bands of p53 and MDM2 could be seen in cells transfected with pwtp53 and pMDM2. Meanwhile，the relative larger molecular weight bands were also seen in cells transfected with pSUMO-1 which represented the p53 and MDM2 protein modification by SUMO-1. Merely the trace of p53 protein was detected in cells not transfected with any plasmid or only transfected with empty plasmid and pSUMO-1. In cells transfected with pwtp53 and pwtp53+pSUMO-1，the apoptosis rates were (16.79±1.62)%and (18.15±1.36)%. When transfected with pwtp53+pMDM2，the rate decreased to (5.17±1.23)%. The apoptosis rate would come up again to (14.06±1.84)% after transfected with pwtp53+pMDM2+pSUMO-1 and the difference of rates were significant compared to the cells transfected with pwtp53+pMDM2 (PH＜0.01）. The apoptosis rates in other cells were less than 2% and had no significant difference. Conclusion SUMO-1 could increase the apoptosis induced by wild-type p53 plasmid transfection in HepG2 cells through combining to p53 protein or its post-translational modification and inhibiting p53 degradation by MDM2.
Objective To observe the effects of taurine on ventricular remodeling of rats with acute myocardial infarction (AMI) though the establishment of rat AMI model by ligating the left anterior descending coronary branch. Methods Sixty 8-week-old male Wistar rats were randomly divided into four groups: sham group, AMI group, small-dose and high-dose taurine group, with 15 rats in each. Rats in the AMI group and taurine groups received ligation of the anterior descending coronary branch to establish an animal model of AMI. Meanwhile, rats in the sham group were subjected to sham coronary ligature. From the next day of the operation, rats in the taurine groups were dosed orally per day with taurine 300 mg/kg or 400 mg/kg for 8 weeks, respectively. Echocardiographic images were acquired before and 8 weeks after the operation, to get the indexes such as left ventricular end systolic diameter (LVIDs), left ventricular end diastolic diameter (LVIDd), left ventricular posterior wall end diastolic thickness (LVPWd), left ventricular ejection fraction (LVEF), fractional shortening (FS), mitral inflow velocity E (E), mitral inflow velocity A (A), and E/A ratio, and all the measurements above were expressed as the average of 6 consecutive cardiac cycles. After the animals were executed, cardiac mass and left ventricular mass were measured, and cardiac mass index (CMI) and left ventricular mass index (LVMI) were calculated. Brain natriuretic peptide (BNP) in all groups were measured by enzyme-linked immunosorbent assay before and 8 weeks after the operation. Results In comparison with the AMI group, CMI, LVMI, LVIDd and LVIDs of the small-dose and high-dose taurine groups were lower, and LVPWd, LVEF, FS and E/A were higher (P<0.05). Plasma BNP level in the AMI group and two taurine-treated groups were higher than that in the sham group, and it was the highest in the AMI group (P<0.05). Conclusion Taurine has a protective effect on ventricular remodeling in rats with AMI, and the protective effect is dose-dependent.
Objective To summarize and analyze the clinical data of maple syrup urine disease (MSUD) patients to explore the correlation among clinical phenotype, biochemical markers and genotype. Methods The clinical data of 11 children with MSUD who were admitted to Guangzhou Women and Children’s Medical Center of Guangzhou Medical University between January 2011 and October 2016 were retrospectively collected. According to the clinical symptoms and prognosis, they were divided into classic type group (n=6) and intermediate/thiamine-effective group (n=5). The differences in biochemical metabolic markers between the two groups were compared, and the correlation between genotype and phenotype was analyzed. Results Compared to the intermediate/thiamine-effective group, the blood gamma-glutamyltransferase (γ-GT) level in the classic type group was significantly higher [158.00 (122.80, 309.30) vs. 11.00 (10.50, 14.00) U/L, P=0.004], and the globulin [(15.55±3.45) vs. (24.26±4.37) g/L, P=0.018] and lactate [1.05 (0.98, 1.68) vs. 2.10 (1.75, 2.70) mmol/L, P=0.030] levels in the classic type group were significantly lower, while the levels of alanine aminotransferase, aspartate aminotransferase and total bile acid were not different between the two groups (P>0.05). The plasma concentrations of leucine in the classic type group were higher than that in the intermediate/thiamine-effective group [(3748.20 (3135.00, 4936.00) vs. 620.40 (531.20, 1150.00) μmol/L, P=0.004]. The γ-GT level was positively correlated with the leucine level (rs=0.826, P=0.003), the leucine level was positively correlated with the iso-leucine level (rs=0.827, P=0.003), and the iso-leucine level was positively correlated with the valine level (rs=0.636, P=0.040). The results of gene sequencing showed that the 11 patients carried BCKDHA (n=4) and BCKDHB (n=7) gene mutations, respectively. Of these, 6 patients with BCKDHB gene mutations were classic type. Conclusion The prognosis of MSUD is closely correlated to blood γ-GT and branched-chain amino acids levels, as well as with genotype.
Objective To investigate the clinical application value of GeneXpert Mycobacterium tuberculosis (MTB)/ rifampin (RIF) in urine samples for tuberculosis diagnosis. Methods The patients with clinically highly suspected tuberculosis admitted to West China Hospital of Sichuan University between January 1, 2018 and June 1, 2023 were selected retrospectively. The diagnostic efficacy of urine GeneXpert MTB/RIF detection, such as sensitivity, specificity, positive predictive value, and negative predictive value, were retrospectively analyzed to evaluate its clinical value in the diagnosis of tuberculosis. Correlation analysis was further conducted to explore the correlation between positive levels of GeneXpert MTB/RIF in urine samples and laboratory test indicators. Results A total of 400 patients were included. Among them, 163 cases were in the clinical tuberculosis group and 237 cases were in the clinical non tuberculosis group. In the clinical tuberculosis group, 112 cases were urogenital tuberculosis patients and 51 cases were non-urogenital tuberculosis patients. The sensitivity, specificity, positive predictive value, and negative predictive value of urine GeneXpert MTB/RIF in the diagnosis of tuberculosis were 55.2%, 97.5%, 93.8% and 76.0%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of urine GeneXpert MTB/RIF in the diagnosis of urogenital tuberculosis were 65.2%, 92.0%, 76.0% and 87.2%, respectively, and the diagnostic sensitivity was further improved. Correlation analysis showed that the positive degree of urine GeneXpert MTB/RIF was correlated with the levels of hemoglobin, serum total protein, blood serum albumin, and other indicators. Conclusions Urine GeneXpert MTB/RIF detection offers high sensitivity and specificity in the diagnosis of tuberculosis, especially in urogenital tuberculosis, which is helpful for the early and rapid diagnosis of tuberculosis patients. The positive degree reported by the GeneXpert MTB/RIF in urine may indicate disease severity.
Objective To evaluate the inhibiting effect of adenosine on rat retinal ganglion cells (RGC) death induced by P2X7 and N-methyl-D-aspartate (NMDA) receptor. Methods (1) Long-Evan neonatal rats were back labeled with aminostilbamidine to identify RGC. The viability of RGC affected by P2X7 excitomotor BzATP (50 mu;mol/L), glutamate receptor excitomotor NMDA (100 mu;mol/L) and adenosine (300 mu;mol/L) was detected. (2) RGC from the retinae of unlabeled neonatal rats were cultured in vitro. After labeled with Fura-2 methyl acetate, an intracellular calcium indicator, the effect of BzATP, NMDA and adenosine on intracellular Ca2+ level was detected byCa2+ imaging system. Results Both BzATP (50 mu;mol/L) and NMDA(100 mu;mol/L) could kill about 30% of the RGC. Cell death was prevented by adenosine (300 mu;mol/L) with the cell viability increased from (68.9plusmn;2.3)% and (69.9plusmn;3.2)% to (91.2plusmn;3.5)% (P＜0.001) and (102.1plusmn;3.9)% (P＜0.001), respectively. BzATP (50 mu;mol/L) led to a large, sustained increase of intracellular Ca2+ concentration to (1183plusmn;109) nmol/L. After the adenosine intervened, Ca2+ concentration increased slightly to (314plusmn;64) nmol/L (P＜0.001). Conclusion Adenosine may prevent RGC death and increase of intracellular Ca2+ concentration from P2X7and NMDA receptor stimulation. (Chin J Ocul Fundus Dis, 2007, 23: 133-136)
Retinal neuronal cells are crucial in the formation of vision. Injury or death of these cells may lead to irreversible damage to visual function due to their low regenerative capacity. The P2X7 receptor is a trimeric adenosine triphosphate (ATP)-gated cation channel. Recent studies have shown that P2X7 receptor plays a role in retinal neuronal death. In a series of animal models, when exposed to conditions of hypoxia or ischemia, elevated ocular pressure, trauma and exogenous agonists, P2X7 receptor activated by extracellular ATP can cause death of retinal neuronal cells such as retinal ganglion cells and photoreceptor cells through direct or indirect pathways. Blocking the expression and function of P2X7 receptor by its specific antagonist and gene knocking-out, the loss of retinal neuronal cells is significantly attenuated. P2X7 receptor may become a potential novel neuroprotective target for diseases related to the loss of retinal neurons.
ObjectiveTo systematically review the relationship between T309G polymorphism of murine double minute 2 (MDM2) gene and susceptibility of prostate cancer. MethodsThe PubMed, Embase, WanFang Data, CNKI databases were electronically searched to collect case-control studies related to the objectives from inception to May, 2023. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using Stata 14.0 software. ResultsA total of 10 studies involving 5 781 patients and 5 477 healthy controls were included. The results of meta-analysis showed that the MDM2 gene T309G polymorphism was not associated with preeclampsia (allele model G vs. T: OR=0.89, 95%CI 0.77 to 1.04, P=0.13; homozygote model GG vs. TT: OR=0.86, 95%CI 0.64 to 1.16, P=0.32; heterozygote model TG vs. TT: OR=1.04, 95%CI 0.86 to 1.26, P=0.12; dominant model GG+TG vs. TT: OR=0.96, 95%CI 0.89 to 1.04, P=0.36; recessive model GG vs. TG+TT: OR=0.84, 95%CI 0.63 to 1.14, P=0.27). The results of subgroup analysis based on ethnicity and source of control were similar to the overall results. Sensitivity analysis showed that the results were robust. Conclusion Current evidence shows that the MDM2 gene T309G polymorphism is not associated with prostate cancer susceptibility. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.
Objective To explore the effects of drugs on functions of mitochondria in retinal nerve cells, and to lay a foundation of the investigation of drug protection for retinal nerve cells. Methods Cultivation of the retinal nerve cells of 8 eyes of neonatal calves was performed. The changes of fluorescent density of the mitochondria of cultured cells labeled by dye rhodamine 123 (Rh123) before and after the activation of the medicines, including ferulic acid (FA), arginine, glycine,taurine, vitamine E and brain derived neurotrophic factor( BDNF) respectively, were detected by laser-scanning confocal microscopy. Results FA with the concentration of 500 μg/ml led the diphasic variation of the fluorescent intensity of mitochondria. After scanning for 60.772 seconds when treated with FA firstly, the fluorescent intensity decreased rapidly (from 45.425±4.153 to 22.135±5.293); while after 112.774 seconds when treated secondly, the in tensity increased obviously (from 19.655±4.383 to 28.247±4.764), and after 168.773 seconds when treated thirdly the intensity still increased. After scanning for 56.457 seconds when treated with vitamin E (12.5 mg/ml), the fluorescent in tensity increased obviously (from 88.255±5.039 to 111.273±4.529), which suggested that vitamin E with the concentration of 12.5 mg/ml strengthen the fluorescent intensity. After scanning for 58.147 and 134.148 seconds when treated with BDNF(50 ng/ml) respectively, the fluorescent intensity increased obviously (from 69.115±5.038 to 77.225±5.131) which suggested that BDNF with the concent ration of 50 ng/ml led the increase of the fluorescent intensity. Glycine (2.5 mg/ml) and arginine(30 mg/ml) didn’t affect the fluorescent intensity of mitochondria, and taurine (6.25 mg/ml) caused the appreciable decrease of the fluorescent intensity . Conclusion FA, BDNF and vitamin E may promote the metabolism of retinal nerve cells via the path of mitochondria, while amino acids may adjust the activation of retinal nerve cells through other ways. (Chin J Ocul Fundus Dis，2004，20：229-232)