[Follow up analysis of 6 patients with severe trimethyltin chloride poisoning for 4 years].

Objective: Objective to investigate the health changes of patients with severe trimethyltin chloride (TMT) poisoning in four years. Methods: Six patients with severe TMT poisoning treated in the First Affiliated Hospital of Gannan Medical College in August 2016 were numbered 1, 2, 3, 4, 5 and 6 respectively. The patients were followed up 0.5, 2 and 4 years after poisoning and compared and analyzed. The follow-up contents include: symptom degree, score of simple mental intelligence examination scale (MMSE) and modified Rankin Scale (MRS) , cranial magnetic resonance imaging (MRI) , EEG, etc. Results: The symptoms of dizziness, headache, chest tightness, palpitation, nausea and vomiting decreased gradually in 6 patients. The symptoms of speech disorder and memory decline in No.1, 2 and 3 patients gradually increased, and the scores of MMSE and Mrs gradually decreased; Patients No.4, 5 and 6 had improved speech disorder, but their memory decreased, MMSE and Mrs scores were still flat, and mild cognitive impairment. The brain atrophy of No.1, 2 and 3 patients was aggravated, which showed obvious atrophy of hippocampus, temporal lobe, insular lobe and cerebellum and enlargement of ventricle; There was no significant change in brain atrophy in No.4, 5 and 6 patients. Conclusion: The neurotoxic symptoms in the later stage of severe TMT poisoning are still serious, and the neurotoxic time is long.

Isolation, identification and pathogenicity of Vibrio harveyi, the causal agent of skin ulcer disease in juvenile hybrid groupers Epinephelus fuscoguttatus × Epinephelus lanceolatus.

The hybrid grouper, Epinephelus fuscoguttatus (♀) × Epinephelus lanceolatus (♂), is a newly bred cultivated marine fish species of high economic value. However, a skin ulcer disease with high mortality has occurred, and the responsible pathogen remains unknown. In this study, we summarized the epidemic status and external signs of this disease. We screened potential pathogens and finally isolated one bacterial strain ML01 from affected fish. We subjected healthy juvenile hybrid groupers to bacterial challenge tests with the isolate by immersion, immersion after dermal abrasion and intraperitoneal injection, respectively. Within 14 days post-infection, the isolate ML01 caused mass mortality of juveniles infected via immersion after dermal abrasion or intraperitoneal injection. Diseased juveniles displayed obvious signs of skin ulcers. The median lethal dose of ML01 by intraperitoneal injection was 1.10 × 105 colony-forming units. ML01 was identified as Vibrio harveyi by bacterial morphology, analytical profile index identification, 16S rDNA sequencing and multilocus sequence analysis. Antibiotic susceptibility tests showed that ML01 was sensitive to ceftriaxone, doxycycline and minocycline. The results of this study suggest that V. harveyi is the causal agent of skin ulcer disease in juvenile hybrid groupers, thus providing a basis for effective control and prevention of this disease.

[Effect of SET deficiency on the trichloroethylene-induced alteration of cell proliferation and cell apoptosis and DNA methylation in human hepatic L-02 cells].

OBJECTIVE: To compare the trichloroethylene (TCE) -induced alteration in cell proliferation, cell apoptosis, histone deacetylase activity and expression levels in human hepatic L-02 cells (L-02 cells) and SET deficient cells, and reveal the TCE-induced effect in histone modification and the role of SET on epigenetic pathway. METHODS: The L-02 cells and preestablished SET deficient cells were treated with different TCE concentrations. For the changes of cell proliferation level and apoptosis rate, The L-02 cells and SET deficiency cells without TCE treatment were served as the control group, the TCE treatment was in the concentration of 2.0 and 8.0 mmol/L for 24 h. For histone deacetylase activity and expression levels, the TCE treatment was in the concentration of 0.25, 0.50, 1.0, 2.0, 4.0, and 8.0 mmol/L for 24 h. RESULTS: After treatment with TCE for 24 h, the cell proliferation level was significantly decreased and the apoptotic rate was significantly increased in both cell lines. When concentration of TCE were reached to 8.0 mmol/L, the difference of cell proliferation level and apoptotic rate between two groups was statistically significant (t=-4.362 for proliferation level and t=23.950 for apoptotic rate, both P<0.05). After treatment with TCE for 24 h in various concentration (0, 0.25, 0.50, 1.00, 2.00, 4.00 and 8.00 mmol/L) , the activity of histone deacetylases was significantly increased in both cell lines. When the TCE concentration were high than 0.50 mmol/L, compared with control group of L-02 cells, the enzymes activity were significantly increased (F=403.26, P<0.001). When TCE concentration was reached 1.00 mmol/L, the enzyme activity is highest. Compared with control group of SET deficiency cells, the enzyme activity was significantly increased when TCE concentration was reached 1.00 mmol/L (F=44.01, P<0.001). When concentration of TCE reached 0.50 mmol/L, the difference of enzyme activity between two groups was statistically significant. For the protein expression, compared with control group of L-02 cells, TCE exposure can induced a significant increased expression level of HDAC2 in TCE-treated L-02 cells (F values were 79.99, P<0.001). But the alteration in SET deficiency cells was not significant. CONCLUSION: TCE exposure can induce a significant alteration on cell proliferation, apoptotic rate and, the activity and expression on histone deacetylases. SET deficiency can attenuate the TCE-induced alteration in histone modification in L-02 cells. Our results indicated that SET is involved in the mechanism of TCE-induced cytotoxicity and epigenetic regulation in L-02 cells.

Effects of AFP gene silencing on Survivin mRNA expression inhibition in HepG2 cells.

We investigated the effects of alpha-fetoprotein (AFP) gene silencing on Survivin expression in HepG2 cells. Small interfering RNA technology was used to downregulate AFP expression in HepG2 cells. An enzyme-linked immunosorbent assay was used to measure AFP concentration in the supernatant before and after transfection. An MTT assay was used to detect cell proliferation activity before and after transfection. We performed flow cytometric analysis to detect the cell apoptosis rate, and reverse transcription-polymerase chain reaction to detect Survivin mRNA levels before and after transfection. Forty-eight hours after transfection, AFP concentration in the supernatant of the experimental group significantly decreased, hepatocellular carcinoma cell growth was inhibited by 43.1%, and the apoptosis rate increased by 24.3%. Survivin mRNA expression was reduced by 78.0% in HepG2 cells. These indicators in the control group and in the blank group did not change significantly. Silencing of AFP expression in HepG2 cells can effectively inhibit the growth of hepatoma cells and promote apoptosis, which may be useful for reducing intracellular Survivin mRNA levels.