Effect of pranlukast on neonatal rats with periventricular leukomalacia / 中国当代儿科杂志

OBJECTIVE@#To study the effect of pranlukast (Pran) on neonatal rats with periventricular leukomalacia (PVL).@*METHODS@#The rats, aged 3 days, were randomly divided into a sham-operation group, a PVL group, and a Pran group. A rat model of PVL was prepared by right common carotid artery ligation and postoperative hypoxia. The rats in the sham-operation group were given isolation of the right common carotid artery without ligation or hypoxic treatment. The rats in the Pran group were given intraperitoneal injection of Pran (0.1 mg/kg) once every 12 hours, for 3 consecutive days, and those in the sham-operation group and the PVL group were given intraperitoneal injection of an equal volume of normal saline. On day 14 after modeling, hematoxylin-eosin (HE) staining was used to observe the pathological changes of brain tissue; immunofluorescent staining was used to measure the expression of myelin basic protein (MBP) in brain tissue (n=8); Western blot was used to measure the expression of cyclic nucleotide phosphodiesterase (CNPase), MBP, and G protein-coupled receptor 17 (GPR17) (n=8). On day 21 after modeling, Morris water maze test was used to evaluate the learning and memory abilities of rats in each group (n=8).@*RESULTS@#The results of HE staining showed that the PVL group had greater pathological changes of white matter than the sham-operation group, and compared with the PVL group, the Pran group had a significant improvement in such pathological changes. The results of immunofluorescence assay showed that the PVL group had a lower mean fluorescence intensity of MBP than the sham-operation group (P<0.05), and the Pran group had a higher mean fluorescence intensity of MBP than the PVL group (P<0.05). Western blot showed that compared with the sham-operation group, the PVL group had significantly lower relative expression of MBP and CNPase (P<0.05) and significantly higher relative expression of GPR17 (P<0.05), and compared with the PVL group, the Pran group had significantly higher relative expression of MBP and CNPase (P<0.05) and significantly lower relative expression of GPR17 (P<0.05). Morris water maze test showed that compared with the sham-operation group, the PVL group had a significant increase in escape latency and a significant reduction in the number of platform crossings, and compared with the PVL group, the Pran group had a significant reduction in escape latency and a significant increase in the number of platform crossings (P<0.05).@*CONCLUSIONS@#Pran can alleviate brain damage, promote myelination, and improve long-term learning and memory abilities in neonatal rats with PVL, possibly by reducing the expression of GPR17.

The influence of microcystin-LR on monocytes and lymphocytes of mice / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the influence of microcystin-LR (MC-LR) on monocytes and lymphocytes in blood of mice and to find a sensitive index of toxic effects.</p><p><b>METHODS</b>Specific pathogen free Kunming male mice, aging 1 month-old,were randomly divided into 5 groups by weights, 7 mice for each group. The mice in 5 groups were exposed to MC-LR through intraperitoneal injection at 0, 3.125,6.250, 12.500 and 25.000 µg/kg respectively for 7 days. Then cytokine levels in the serum were measured by radioimmunoassay, DNA-protein crosslinks (DPC) was measured by the SDS/KCl precipitation technique, and the phagocytosis and ROS of leukocytes were detected by flow cytometry.</p><p><b>RESULTS</b>The levels of interleukin 6 in the 6.250, 12.500 and 25.000 µg·kg(-1)·d(-1) dose groups were (346.837 ± 25.536), (360.847 ± 37.886) and (434.245 ± 35.858)pg/ml respectively, which were significantly higher than those in the control group which the value was (232.775 ± 32.816) pg/ml (t values were -7.258, -6.760 and -10.966 respectively, P values were all < 0.05).While the level of tumor necrosis factor-alpha was(10.782 ± 0.966) fmol/ml in 25 µg·kg(-1)·d(-1) dose group was statistically lower than it in the control group which the value was (16.878 ± 3.378) fmol/ml (t value was 4.591, P < 0.05). The DPC levels of lymphocytes in 6.250, 12.500 µg·kg(-1)·d(-1) dose group were (242.576 ± 7.545),(241.472 ± 2.793) ng/ml,higher than it in the control group while the value was (228.657 ± 4.130) ng/ml (t value was -4.282, -6.801, P values were all <0.05). The fluorescence intensity of DCF in lymphocytes in the 4 treated groups were separately 3299.37 ± 120.54, 3281.38 ± 58.34, 3308.06 ± 136.12 and 3346.92 ± 108.69, all significantly lower than 3770.81 ± 131.39 in the control group (t values were 6.995, 9.007, 6.472 and 6.577 respectively, and P values were all <0.05). The fluorescence intensity of DCF in monocytes in the 4 treated groups (3271.51 ± 140.79, 3270.05 ± 117.92, 3326.90 ± 114.39 and 3292.49 ± 145.97 respectively) were also significantly lower than the value in the control group was 3841.72 ± 130.92 (t values were 7.847, 8.584, 7.835 and 7.411 respectively, P values were all <0.05). There was no significant difference in other index among the four experiment groups and the control group.</p><p><b>CONCLUSION</b>The MC-LR administered via intraperitoneal injection to mice induced the alterations of some cytokines of monocytes and lymphocytes in blood. By comparison, the ROS of leukocyte was the most sensitive index.</p>

The establishment and application of the method with virus concentration and detection in drinking water / 中华预防医学杂志

<p><b>OBJECTIVE</b>This study aimed to construct an effective method to concentrate and detect virus in drinking water, and human adenovirus pollution status in actual water samples was monitored by constructed method.</p><p><b>METHODS</b>The concentration efficient of NanoCeram filter for the first concentration with source water and drinking water and the concentration efficient of the different concentrations of PEG 8000 for the second concentration were assessed by spiking f₂ bacteriophage into water samples. The standard of human adenovirus for real-time PCR was constructed by T-A clone. The plasmid obtained was identified through sequence analyzing and consistency check comparing to target gene fragment was conducted by using blast algorithm. Then, real-time PCR was constructed to quantify the concentration of human adenovirus using the plasmid as standard. Water samples were concentrated by using NanoCeram filter on the spot and then concentrated for the second time by PEG/NaCl in 2011. The DNA of concentrated samples were extracted for the quantification of human adenovirus in real-time PCR subsequently to monitor the pollution of human adenovirus in water.</p><p><b>RESULTS</b>For the first concentration by NanoCeram filter, the recovery rates were (51.63 ± 26.60)% in source water and (50.27 ± 14.35)% in treated water, respectively. For the second concentration, the highest recovery rate was reached to (90.09 ± 10.50)% at the concentration of 0.13 kg/L of PEG 8000. The sequence identity score of standard of adenovirus for real time PCR and adenovirus gene was 99%, implying that it can be successfully used to quantification with human adenovirus. The levels of human adenovirus in the water samples sampled in 2011 ranged from 4.13×10³ to 2.20×10⁶ copies/L in source water, while range from 5.57×10² to 7.52×10⁵ copies/L in treated water and the removal efficiency range was (75.49 ± 11.71)%.</p><p><b>CONCLUSION</b>NanoCeram filers combined with PEG/NaCl was an effective method to concentrate virus in aquatic environment. There was a large number of human adenovirus in source water, and it is not sufficient to remove them thoroughly through conventional water treatment processes.</p>