Objective To study the effects of zinc-metallothionein (ZnMT) on the cadmium-induced oxidative damage of liver and kidney in mice. Methods The model of laboratory animal was established by 14 d-cadmium exposure to Kunming mice. Then the cadmium-poisoning mice were grouped as Cd-ZnMT group and Cd-ZnSO4 group and perfused orally by solution of ZnMT and ZnSO4 for 14 days respectively. The morphological changes of liver and kidney were observed by electron microscope. The contents of malonydiadehyde (MDA), the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in supernatant fluid of liver and kidney were determined. Results The decreases of the contents of MDA, the increases of the activities of SOD and GSH-Px in liver and kidney of mice in Cd-ZnMT and Cd-ZnSO4-exposure group were observed compared with those in cadmium-exposure group, the dose-effect relationships were also found. The increases of the activities of SOD and GSH-Px, the decrease of contents of MDA of liver and kidney, were found in Cd-ZnMT-exposure group compared with those of Cd-ZnSO4-exposure group, but without statistical significances. The morphological damages of liver and kidney observed by electron microscope in mice of cadmium-exposure group were more serious than those in mice treated with solution of ZnMT and ZnSO4 after cadmium exposure. Conclusion ZnMT could repair the lipid peroxidative damages in liver and kidney in mice induced by exposure to cadmium in a certain degree.

Objective To study the inhalation toxicity of volatile organic compounds in mice. Methods The VOC mixture was prepared according to the monitoring data on indoors air. NIH mices were exposed to the gaseous mixture at the doses of 80.00 mg/m3,64.00 mg/m3,51.28 mg/m3,40.96 mg/m3,32.79 mg/m3 and 26.21 mg/m3 to determine the acute toxicity,and at the doses of 10.75 mg/m3,5.38 mg/m3,2.69 mg/m3 to examine the toxic effect on the weight,organ coefficient,the activity of GSH-Px and SOD and the contents of MDA in the serum. The accumulative toxicity was determined. Results The LD50 of acute inhalation toxicity was 53.74 mg/m3.After exposed to this gaseous mixture for 30 days,the body weight decreased significantly,the organ coefficient of liver and kidney changed,and the activity of GSH-Px and SOD decreased,the contents of MDA in serum increased. The accumulation coefficient was above 5. Conclusion This VOC mixture has weak accumulation toxicity in mice,but have some other toxicity.

Objective To observe the effects of substance P (SP), NK1 receptor antagonist and nitric oxide synthase (NOS) inhibitors on the secretion of nitric oxide (NO) and expression of inducible NOS (iNOS) by immortalized human keratinocyte line HaCaT. Methods The NO level in supernatant of cultured HaCaT cells was measured by nitrate reductase assay after treatment with different concentrations (10-9 to 10-6 mol/L) of SP, or the combination of SP (10-8 mol/L) and spantide (3×10-7 mol/L), aminoguanidine (10-7 mol/L), 7-nitroindazole (10-6 mol/L) or L-NAME (10-5 mol/L) for various durations. Reverse transcription-PCR was performed to measure the expression of iNOS mRNA in HaCaT cells incubated with SP of 10-8 mol/L for 1, 24 and 48 hours. Results The SP of 10-9 to 10-6 mol/L significantly induced the production of NO by HaCaT cells, and the highest level of NO was observed in HaCaT cells treated with SP of 10-8 mol/L. The synthesis of NO by HaCaT cells induced by SP was inhibited by Spantide of 3 × 10~7 mol/L at all time points (30 minutes, 1, 3, 6, 12, 24 hours, all P< 0.01), by L-NAME of 10-5 mol/L at 3 time points (30 minutes, 1, 24 hours) and by 7-nitroin-dazole of 10-6 mol/L at 2 time points (30 minutes, 1 hour, both P< 0.05), but not by aminoguanidine of 10-7 mol/L at any time point (all P > 0.05). After treatment with SP of 10-8 mol/L, the relative mRNA expression of iNOS was 0.199 ± 0.018 and 0.516 ± 0.030 at 24 and 48 hours, respectively, and there was a statistical difference between the two time points (P < 0.01). Conclusions SP can reinforce the secretion of NO by HaCaT cells via NK1 receptor activation, but iNOS is unlikely to be the primary origin of NO secreted by HaCaT cells induced by SP.

OBJECTIVETo establish a method for determination of 7-ethyl-10-hydroxycamptothecin (SN-38) in microdialysates from rat brain.

METHODSThe concentrations of SN-38 were measured by LC-MS/MS method with Agilent Eclipse Plus C18 (2.1 mm ×100 mm, 1.8 μm) reversed phase column using acetonitrile-0.1% methanoic acid as mobile phase with gradient elution at a flow rate of 0.3 ml/min and temperature at 35 degree. Multiple reaction monitoring using the precursor to product ion combinations of m/z 393.1→349.1 was performed to detect SN-38 in microdialysates from rat brain.

RESULTSBlank microdialysate had non-interference. The method was linear over the concentration range of 0.1015-1015 ng/ml (r=0.9995); and the lower limit of quantification (LOQ) was 0.1015 ng/ml. The recovery of assay for SN-38 ranged from 97.54%-100.60%. The intra- and inter-day precision and stability were both well. The concentrations of SN-38 in brain microdialysates presented pharmacokinetics process and achieved the peak after 220 min.

CONCLUSIONThe fully validated LC-MS/MS analytical method has high specificity and sensibility, which can be used effectively to analyze SN-38 in microdialysates from rat brain.

Animals ; Brain Chemistry ; Camptothecin ; analogs & derivatives ; analysis ; Chromatography, Liquid ; methods ; Male ; Microdialysis ; Rats ; Rats, Sprague-Dawley ; Sensitivity and Specificity ; Tandem Mass Spectrometry ; methods

Objective To investigate the role of Notch signaling in the progression of peritoneal fibrosis in a rat model induced by high glucose dialysate. Methods Male Sprague Dawley rats were subjected to daily peritoneal dialysis (PD) with a lactate-buffered solution containing 4.25% glucose. They were sacrificed at 2 and 4 weeks after PD. The parietal thickness was measured with Masson staining. The expression of TGF-β1, E-cadherin, α-SMA and collagen Ⅰ was examined by immunoblotting. The expression of Notch ligand Jagged-1 and the negative Notch signaling regulato--Numb was analyzed by both immunoblotting and RT-PCR. The expression of a Notch nuclear target gene Hcs-1 was examined by RT-PCR. Results Both HE and Masson trichrome staining revealed an increase in peritoneal thickness with a loss of mesothelial cells and a rich of collagen matrix deposition in the submesothelial zone was evident at 4 weeks after PD. Meanwhile, compared to healthy rats, the expression of TGF-β1, ct-SMA and collagen Ⅰ was significantly increased, but the expression of E-cadherin was decreased in peritoneum after PD treatment. It was difficult to detect the Jagged-1 and Hes-1 expression in normal peritoneum, but their expression was graduaUy increased after PD. In contrast, the expression level of Numb, a negative regulator of Notch signaling, was dramatically decreased after PD. Conclusions Notch signaling is activated during the process of PD-induced peritoneal fibrosis and the activation of Notch signaling is associated with the loss of negative regulation of Notch signaling via decreased expression of Numb. Inhibition of Notch signaling via overexpression of its negative regulators such as Numb may be a novel therapeutic approach for peritoneal fibrosis in PD patients.

OBJECTIVE: To assess the influence of rs2910164 G/C single nucleotide polymorphism (SNP) of the miR-146a gene on its expression and susceptibility to gastric cancer. METHODS: Fifty three gastric cancer patients and six gastric cancer cell lines were selected for determining the miR-146a expression by Taqman quantitative PCR. A model was constructed to assess the influence of miR-146a overexpression on the growth of AGS gastric cancer cells. A case-control study involving 417 gastric cancer patients and 420 cancer-free individuals was then conducted, and the allelic and genotypic frequencies of the rs2910164 G/C SNP were compared. The genotypes of all subjects were determined by using a Taqman allelic discrimination assay. A Taqman assay was also used to quantify mature and pri-miR-146a transcripts among 65 gastric cancer patients with known genotypes. RESULTS: The expression of miR-146a was down-regulated among the 53 gastric cancer patients and six gastric cancer cell lines. Over-expression of miR-146a has suppressed the growth of gastric cancer by inhibiting the G1/S-phase transition of AGS cells. The case-control study showed that subjects with GC/CC genotypes had significantly lower risk for gastric cancer compared with those with GG genotype. In addition, miR-146a G/C SNP has significantly increased the level of mature miR-146a in those with GC/CC genotype compared with GG genotype. CONCLUSION Down-regulation of miR-146a may play an important role in the pathogenesis of gastric cancer. The rs2910164 polymorphism of the miR-146a gene may reduce the risk of gastric cancer by influencing the processing of mature miR-146a.
Case-Control Studies ; Genotype ; Humans ; MicroRNAs/genetics* ; Polymorphism, Single Nucleotide ; Stomach Neoplasms/genetics*

Objective: To explore the association between coagulation indicators and all-cause mortality in sepsis-related acute kidney injury (AKI) patients. Methods: Clinical data of patients with sepsis-related AKI admitted to the First Affiliated Hospital of Guangxi Medical University from June 10, 2016 to June 10, 2018 were retrospectively analyzed. The patients were divided into death group and survival group according to the outcome of 28 d. The risk factors of all-cause mortality in sepsis-related AKI patients were analyzed. Receiver operating characteristic curve (ROC) was used to evaluate the prognostic value of independent risk factor for the death of sepsis-related AKI patients and Kaplan-Meier method was used to draw the survival curve. Results: A total of 214 patients with sepsis-related AKI were enrolled into this study. Their age was (57.90±16.96) years old, and the ratio of male to female was 2.57∶1. There was at least one abnormal coagulation indicator in 74.77%(160/214) of patients, and multiple organ dysfunction syndrome (MODS) in 37.38% of patients. The 28-day all-cause mortality was 28.04%(60/214). Prothrombin time, activated partial thrombin time (APTT), international standardized ratio, thrombin time, procalcitonin, abnormal coagulation indicators and the incidence of MODS in the death group were higher than those in the survival group, while body weight, hemoglobin, the percent of neutrophile granulocyte, platelet count, prothrombin activity, serum albumin and the proportion of renal replacement therapy (RRT) were lower than those in the survival group (all P<0.05). Cox regression analysis suggested that sepsis-related AKI patients with prolonged APTT had a higher risk for all-cause death (HR=2.610, 95%CI 1.077-6.326, P=0.034). The Kaplan-Meier survival curve indicated that 28 d survival rate of APTT extension group was lower than that of the non-APTT extension group (37.1% vs 70.6%, Log-rank χ²=16.881, P<0.001), and the average survival time was shorter than that of the non-APTT extension group (21.79 d vs 24.73 d). Conclusions Coagulation abnormalities are common in patients with sepsis-related AKI, which are also correlated to the all-cause death. APTT extension is an independent risk factor for the all-cause death in sepsis-related AKI patients.