Predictive values of serum 8-hydroxydeoxyguanosine on disease progression and prognosis of patients with sepsis / 中华烧伤杂志

Objective: To investigate the values of serum 8-hydroxydeoxyguanosine (8-OHdG) in predicting disease progression and prognosis of patients with sepsis. Methods: The prospective observational research methods were used. A total of 124 patients with sepsis who met the inclusion criteria were admitted to the Department of Emergency of the First Affiliated Hospital of Wenzhou Medical University from April 2015 to July 2016, including 79 males and 45 females, aged (62±15) years. The sepsis-related organ failure assessment (SOFA) scores of all patients on admission and on the second day of admission and their difference (ΔSOFA) were calculated. The patients were divided into non-progression group with ΔSOFA score <2 (n=101) and progression group with ΔSOFA score ≥2 (n=23), and according to the survival during hospitalization, the patients were divided into survival group (n=85) and death group (n=39). Data of patients between non-progression group and progression group, survival group and death group were compared, including the gender, age, days in emergency intensive care unit (ICU), smoking, hypertension, diabetes mellitus, serum white blood cell count, serum C-reactive protein, and serum procalcitonin on admission, and serum 8-OHdG within 24 h of admission. The multivariate logistic regression analysis was used to screen the independent risk factors of disease progression and death during hospitalization in 124 patients with sepsis, the receiver's operating characteristic (ROC) curves were drawn according to the independent risk factors, and the area under the curve (AUC), the best threshold, and the sensitivity and specificity under the best threshold were calculated. The patients were divided into high 8-OHdG group (n=35) and low 8-OHdG group (n=89) according to the best threshold in ROC curve of death during hospitalization. The data including the gender, age, SOFA score on admission, SOFA score on the second day of admission, and ΔSOFA score of patients in the two groups were compared. The survival rates of patients within 90 d of admission in the two groups were compared by the Kaplan-Meier method. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, chi-square test, and Log-rank test. Results: The gender, age, days in emergency ICU, smoking, complicated with hypertension, complicated with diabetes mellitus, serum white blood cell count, serum C-reactive protein, and serum procalcitonin on admission of patients in non-progression group and progression group were similar (P>0.05). The serum 8-OHdG within 24 h of admission of patients in progression group was significantly higher than that in non-progression group (Z=-2.31, P<0.05). Multivariate logistic regression analysis showed that the serum 8-OHdG within 24 h of admission was the independent risk factor for disease progression of 124 patients with sepsis (odds ratio=1.06, with 95% confidence interval of 1.01-1.11, P<0.05). The AUC under the ROC curve of serum 8-OHdG within 24 h of admission to predict disease progression of 124 patients with sepsis was 0.65 (with 95% confidence interval of 0.52-0.79, P<0.05), the optimal threshold was 32.88 ng/mL, and the sensitivity and specificity under the optimal threshold was 52.2% and 79.2%, respectively. The gender, age, days in emergency ICU, smoking, complicated with hypertension, complicated with diabetes mellitus, and serum white blood cell count, serum C-reactive protein, and serum procalcitonin on admission of patients in survival group and death group were similar (P>0.05). The serum 8-OHdG within 24 h of admission of patients in death group was significantly higher than that in survival group (Z=-2.37, P<0.05). Multivariate logistic regression analysis showed that the serum 8-OHdG within 24 h of admission was the independent risk factor for death of 124 patients with sepsis (odd ratio=1.04, with 95% confidence interval of 1.00-1.09, P<0.05). The AUC under the ROC curve of serum 8-OHdG within 24 h of admission to predict death of patients during hospitalization was 0.63 (with 95% confidence interval of 0.52-0.75, P<0.05), the optimal threshold was 32.43 ng/mL, the sensitivity and specificity under the optimal threshold was 51.3% and 84.7%, respectively. The gender and age of patients in high 8-OHdG group and low 8-OHdG group were similar (P>0.05). The SOFA score on admission, SOFA score on the second day of admission, and ΔSOFA score of patients in high 8-OHdG group were significantly higher than those in low 8-OHdG group (with Z values of -2.49, -3.01, and -2.64, respectively, P<0.05 or P<0.01). The survival rate within 90 d of admission of patients in low 8-OHdG group was significantly higher than that in high 8-OHdG group (χ2=14.57, P<0.01). Conclusions: Serum 8-OHdG level is an independent risk factor for disease progression and death in sepsis patients with limited ability for predicting disease progression and prognosis of sepsis of patients. The patients with higher serum 8-OHdG level have higher death risk within 90 d of admission.

Role of the Ca-Calcineurin-Nuclear Factor of Activated T cell Pathway in Mitofusin-2-Mediated Immune Function of Jurkat Cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mitofusin-2 (MFN2), a well-known mitochondrial fusion protein, has been shown to participate in innate immunity, but its role in mediating adaptive immunity remains poorly characterized. In this study, we explored the potential role of MFN2 in mediating the immune function of T lymphocytes.</p><p><b>METHODS</b>We manipulated MFN2 gene expression in Jurkat cells via lentiviral transduction of MFN2 small interfering RNA (siRNA) or full-length MFN2. After transduction, the immune response and its underlying mechanism were determined in Jurkat cells. One-way analysis of variance and Student's t-test were performed to determine the statistical significance between the groups.</p><p><b>RESULTS</b>Overexpression of MFN2 enhanced the immune response of T lymphocytes by upregulating Ca2+ (359.280 ± 10.130 vs. 266.940 ± 10.170, P = 0.000), calcineurin (0.513 ± 0.014 vs. 0.403 ± 0.020 nmol/L, P = 0.024), and nuclear factor of activated T cells (NFATs) activation (1.040 ± 0.086 vs. 0.700 ± 0.115, P = 0.005), whereas depletion of MFN2 impaired the immune function of T lymphocytes by downregulating Ca2+ (141.140 ± 14.670 vs. 267.060 ± 9.230, P = 0.000), calcineurin (0.054 ± 0.030 nmol/L vs. 0.404 ± 0.063 nmol/L, P = 0.000), and NFAT activation (0.500 ± 0.025 vs. 0.720 ± 0.061, P = 0.012). Furthermore, upregulated calcineurin partially reversed the negative effects of MFN2 siRNA on T cell-mediated immunity evidenced by elevations in T cell proliferation (1.120 ± 0.048 vs. 0.580 ± 0.078, P = 0.040), interleukin-2 (IL-2) production (473.300 ± 24.100 vs. 175.330 ± 12.900 pg/ml, P = 0.000), and the interferon-γ/IL-4 ratio (3.080 ± 0.156 vs. 0.953 ± 0.093, P = 0.000). Meanwhile, calcineurin activity inhibitor depleted the positive effects of overexpressed MFN2 on T cells function.</p><p><b>CONCLUSIONS</b>Our findings suggest that MFN2 may regulate T cell immune functions primarily through the Ca2+-calcineurin-NFAT pathway. MFN2 may represent a potential therapeutic target for T cell immune dysfunction-related diseases.</p>

Effect of thalidomide in a mouse model of paraquat-induced acute lung injury and the underlying mechanisms / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the intervention effect of thalidomide on paraquat-induced acute lung injury in mice and its mechanism.</p><p><b>METHODS</b>Male ICR mice were randomly allocated to negative control group (n = 30), thalidomide control group (n = 30), paraquat poisoning group (n = 30), 50 mg/kg thalidomide treatment group (n = 30), 100 mg/kg thalidomide treatment group (n = 30), and 150 mg/kg thalidomide treatment group (n = 30). The negative control group was intraperitoneally injected with the same volume of saline; the thalidomide control group was intraperitoneally injected with thalidomide (150 mg/kg); the paraquat poisoning group was intraperitoneally injected with diluted paraquat solution (22 mg/kg); each thalidomide treatment group was intraperitoneally injected with the same volume of paraquat solution (22 mg/kg) and was injected with thalidomide (50, 100, or 150 mg/kg) 1 h later. All mice were anesthetized and sacrificed at 1, 3, or 7 d after paraquat poisoning, and their lung tissue was collected. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in lung tissue were measured by double-antibody sandwich ELISA; the mRNA expression of nuclear factor-kappa B (NF-κB) was measured by RT-PCR; the protein expression of nuclear NF-kgr;B p65 was measured by Western blot. The pathological changes of lung tissue were observed under light microscope; the wet/dry ratio of the lung was calculated.</p><p><b>RESULTS</b>Compared with the negative control group, the paraquat poisoning group had significantly increased levels of TNF-α, IL-1β, IL-6, NF-κB mRNA, and nuclear NF-κB p65 and wet/dry ratio of the lung (P < 0.05). Compared with the paraquat poisoning group, the thalidomide treatment groups had significantly decreased levels of TNF-α, IL-1β, IL-6, NF-κB mRNA, and nuclear NF-κB p65 and wet/dry ratios of the lung (P < 0.05), and the 150 mg/kg thalidomide treatment group showed the most significant decrease in the levels of TNF-α, IL-1β, IL-6, NF-κB mRNA, and nuclear NF-κB p65. The observation of pathological changes showed that the paraquat poisoning group had the most marked lung tissue damage at 3 d after poisoning, and the lung tissue damage was lessened in the thalidomide treatment groups.</p><p><b>CONCLUSION</b>Thalidomide can reduce paraquat-induced acute lung injury and lung edema. The mechanism may include inhibition of NF-κB activation and expression and downregulation of TNF-α, IL-1β, and IL-6.</p>

Effect of bromoxynil on membrane potential and respiratory control rate in isolated mitochondria from mice liver and intervention effect of NAC / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To demonstrate the effect of bromoxynil on membrane potential and respiratory control rate (RCR) in isolate mitochondria from mice liver tissue in vitro and the intervention of NAC.</p><p><b>METHODS</b>The mitochondrial was randomized to control group, bromoxynil-poisoned group and NAC-protected group. S3, S4 and RCR of the mitochondria in each sample was detected by the method of oxygen electrode. Each sample was stained by JC-1 and the changes of membrane potential of mitochondria were observed under fluorescence microscope.</p><p><b>RESULTS</b>The S3 [(0.031 +/- 0.008) nano atoms oxygen x mg(-1) x min(-1)], RCR (1.820 +/- 0.181) of bromoxynil-poisoned group and RCR (4.253 +/- 0.210) of NAC-protected group were significantly lower than those of control group (P<0.01); the S4 [(0.017 +/- 0.004) nano atoms oxygen x mg(-1) x min(-1)] of NAC-protected group was significantly higher than control group (P<0.01). The S3 [(0.046 +/- 0.005) nano atoms oxygen x mg(-1) x min(-1)] and RCR of NAC-protected group were significantly higher than group B (P<0.01), S4 [(0.011 +/- 0.001) nano atoms oxygen x mg(-1) x min(-1)] of NAC-protected group was significantly lower than bromoxynil-poisoned group (P< 0.01). Observation under fluorescence microscope: the red fluorescence of mitochondria was dim or disappeared in bromoxynil-poisoned group while brightened in NAC-protected group but still dimmer than control group.</p><p><b>CONCLUSION</b>In vitro, the mitochondrial RCR and the mitochondrial membrane potential are decreased after the mitochondria is incubated with bromoxynil, and NAC could improve it.</p>

Oxidative stress of acute paraquat poisoned rats and sodium dimercaptopropane sulfonate intervention / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>to study the oxidative stress of rats with acute paraquat poisoning and the intervention of Sodium Dimercaptopropane Sulfonate (NA-DMPS).</p><p><b>METHODS</b>Eighty male SD rats were randomizedly divided into: the normal control group (n=8), NA-DMPS control group (n=8), the PQ group (n=32, the rats were intraperitoneally injected with 1% PQ solution at the dosage of 20 mg/kg) and the NA-DMPS protected group (n=32). The rats in the groups of normal and NA-DMPS control were sacrificed 1d after administration of NS or NA-DMPS. And the rats in the PQ group and the NA-DMPS protected group were sacrificed at 6h, 1, 3, 7d after poisoning. Samples of serum, bronchoalveolar lavage fluid (BALF) and lung tissue were gathered. The MDA and CAT in serum, BALF and lung homogenate, the glutathione (GSH) in serum and BALF were measured. And the expression of Nuclear factor E2-related factor 2 (Nrf2) mRNA in lung was tested with RT-PCR.</p><p><b>RESULTS</b>Compared with the normal control group, the activities of MDA and CAT in serum, BALF and lung homogenate are higher in both groups of PQ and NA-DMPS protected. And compared with the PQ group, the activities of MDA in serum, BALF and lung homogenate of the NA-DMPS protected group decreased significantly at 6h, 1d after poisoning, whereas the activities of CAT are higher at 6h, 1, 3d in serum and 1, 3d in BALF and lung homogenate (P<0.05 or P<0.001). The serum GSH at 6h, 3d of the NA-DMPS protected group [(730.07 +/- 16.23), (793.66 +/- 7.40)] were higher than those in the PQ group. And the BALF GSH at 1, 3d of the NA-DMPS protected group [(609.75 +/- 6.74), (631.83 +/- 12.03)] were also markedly higher than the PQ group (P<0.05 or P<0.001). The expression of NRF2 mRNA of the lung at 1, 3, 7d in the PQ group [(0.71 +/- 0.061), (1.023 +/- 0.158), (0.969 +/- 0.046)] and the NA-DMPS protected group [(1.005 +/- 0.06), (1.464 +/- 0.166), (1.066 +/- 0.191)] were significantly higher than those in the control groups. Compared with the PQ group, the expression of NRF2 mRNA of the lung increased markedly in the NA-DMPS protected group at 1, 3d (P<0.01).</p><p><b>CONCLUSION</b>Na-DMPS decreases the activity of MDA and increases the activity of CAT, GSH and the expression of Nrf2 mRNA. NA-DMPS can protected rats from PQ intoxication by improving the balance of redox reaction.</p>