[Effects of specimen preservation and transportation on blood paraquat concentration in rats].

Objective: To investigate the effects of duration, temperature and shake on paraquat (PQ) concentration in the blood of PQ-exposed rats during the specinen preservation and transportation. Methods: In March 2021, 60 SD male rats of Specific Pathogen Free class were randomly divided into low-dose group (10 mg/kg PQ) and high-dose group (80 mg/kg PQ). Each group was divided into 5 subgroups (normal temperature group, cold storage group, 37 ℃ storage group, shaking on normal temperature group and shaking on 37 ℃ group), six rats in each subgroup. The rats were given intraperitoneal injection of PQ, 1 h after exposure, the blood samples were obtained by cardiac extraction. After different interventions, the concentrations of PQ were detected and compared before and after the intervention in each subgroup. Results: In the shaking on 37 ℃ group, the results of PQ concentrations in PQ-exposed rats were significantly lower than those before the intervention (P<0.05). In the other subgroups, the results were not significantly different compared with before intervention (P>0.05) . Conclusion: The concentration of PQ in the blood of rats exposed to PQ was decreased by shaking for 4 hours at 37 ℃.

[Effect of chlorpyrifos on autophagy-related protein expression in hippocampal neurons of SD rats].

Objective: To analyze the effect of chlorpyrifos on the expression of autophagy related proteins in rat hippocampal neurons, and to explore the role of autophagy in central nerve injury caused by acute chlorpyrifos poisoning. Methods: In October 2018, 35 male clean grade SD rats were randomly divided into 7 groups according to the observation time point, namely 0.5 d, 1 d, 2 d, 3 d, 5 d and 7 d groups and the control group, with 5 rats in each group. Each observation group was given 81.5 mg/kg chlorpyrifos by gavage, and the control group was given olive oil by gavage. The general conditions and poisoning symptoms of rats were observed continuously after exposure. The expressions of autophagy related proteins Beclin1, P62/SQSTM1 and LC3 in hippocampus were detected by Western blot. The cell morphology and LC3 expression in brain were observed by immunohistochemical staining. Results: Western blot results showed that compared with the control group, the expression of Beclin1 protein in hippocampal neurons of rats in the 1 d, 2 d, and 3 d groups increased, while the expression of P62/SQSTM1 protein in the 0.5 d, 1 d, and 2 d groups decreased, and the expression of LC3 protein was decreased in the 2 d group, and the differences were statistically significant (P<0.05) . The results of immunohistochemistry showed that the hippocampal neurons of rats in the 5 d group were arranged disorderly, and some nuclei contours disappeared, especially in the 7 d group. The LC3 protein was expressed in the cytoplasm, and the expression level gradually increased, reaching a peak on the second day. Conclusion: The early activation of autophagy in rats with acute chlorpyrifos poisoning may be involved in chlorpyrifos induced hippocampal neuronal injury.

[Establishment and evaluation of acute diquat poisoning model in Wistar rats].

Objective: To establish the Wistar rat model of acute diquat poisoning and observe the pathological damage of main target organs. Methods: Thirty-six Wistar rats were randomly divided into six groups (n=6) , including one normal saline control group and five treatment groups which were separately given single-dose of intragastric administration at the doses of 46.2 mg/kg, 77.0 mg/kg, 115.5 mg/kg, 231.0 mg/kg and 346.5 mg/kg. The pathological changes of lung, liver and kidney were observed by hematoxylin and eosin (HE) and Masson staining. The optimal dose was determined according to the general situation and pathological changes. Thirty-six Wistar rats were randomly divided into five treatment groups and one normal saline control group. Treatment groups were given single-dose of intragastric administration according to the optimal dose. The rats were sacrificed at 1st, 3rd, 7th, 11th and 14th day after exposed, respectively. The activity of serum glutamic-pyruvic transaminase (ALT) and glutamic-oxalacetic transaminase (AST) were measured by chemical colorimetry. The pathological changes of lung, liver and kidney were observed by HE and Masson staining. Results: According to 14 d survival rate, the toxic symptoms and pathological changes, 115.50 mg/kg was determined the best dose. Given single-dose of intragastric administration at the doses of 115.50 mg/kg, it was found that the serum AST and ALT activity of rats on the first and third day of exposure was significant higher than those in control group. The results of pathological examination exhibited that in 115.50 mg/kg group, the pathological changes of lung, liver and kidney began to appear on the first day of exposure, the pathological changes were the most serious on the third day, and then gradually alleviated. On the 14th day, the alveolar septum was slightly widened, with inflammatory cell infiltration, local alveolar cavity became narrow, atrophy, peripheral alveolar compensation, bronchi and alveolar septum collagen fiber proliferation; The local renal tubular epithelial cells were enlarged and necrotic; the central vein surrounding hepatic cells showed vacuolar degeneration with punctate necrosis. Conclusion: The rat model of acute diquat poisoning can be successfully induced by single-dose of intragastric administration. The condition of wistar rats and the pathological damage of the main target organs could be observed during the whole course of 115.50 mg/kg administration.

[An analysis of coping styles and subjective well-being among nurses in the emergency treatment room of grade A tertiary hospitals in a province of China].

Objective: To investigate the coping styles and subjective well-being of nurses in the emergency treatment room of grade A tertiary hospitals in a province of China, and to explore the relationship between coping styles and subjective well-being. Methods: In January 2016, 189 nurses in the emergency treatment room were selected from 9 grade A tertiary hospitals in a province of China by random sampling. The general data, coping styles, and subjective well-being of these nurses were analyzed using the general questionnaire, coping style questionnaire, and Campbell index of well-being scale, respectively. Results: The total score of subjective well-being of nurses in the emergency treatment room was 7.54, and the subjective well-being was significantly different between the nurses with different professional titles and between those with different education levels (F=3.46 and 3.47, both P<0.05). The score of illusion coping style differed significantly across the nurses of different ages (F=5.17, P<0.05) , the scores of self-reproach, illusion, and withdrawal coping styles differed significantly across the nurses with different nursing years (F=3.99, 5.30, and 4.97, all P<0.05) , and the score of illusion coping style differed significantly across the nurses with different education levels (F=5.09, P<0.05). Most (71.9%) of the nurses in the emergency treatment room adopted the mature coping style. Subjective well-being was positively correlated with problem-solving, help-seeking, and rationalization (r=0.232, 0.018, and 0.167, all P<0.05) and negatively correlated with withdrawal (r=-0.146, P<0.05) . Conclusion: Most nurses in the emergency treatment room adopt the mature coping style. Their subjective well-being and coping style vary with different ages, nursing years, professional titles, and education levels, and the subjective well-being is relatively low.