Objective To investigate the infestation of common vectors (namely, rodents, flies, mosquitoes, and cockroaches) in rural households in Shanxi province, China, so as to provide a basis for the assessment of environmental health hazards in rural areas. Methods In every August from 2015 to 2017, an investigation was conducted on the infestation of rodents, flies, mosquitoes, and cockroaches from 720 rural households in 20 villages in 5 towns in each of the 36 counties in Shanxi province, and statistical analyses were carried out on the resulted data. Univariate analysis of variance was used to analyze the time and space difference in the infestation of the vectors. Results There were no significant between-year differences in the infestation rates of rodents, flies, mosquitoes, and cockroaches from the rural households in Shanxi province from 2015 to 2017. During the three years, the average rodent infestation rate in the rural households across the province was 31.75%, with the highest infestation rate observed in Datong (61.00%), followed by Shuozhou (56.56%), and the lowest infestation rate was observed in Changzhi (14.89%); the rodent infestation rates in Datong and Shuozhou significantly differed from those in Lyuliang and the other seven cities (F=4.185, P=0.002). The average fly infestation rate in the rural households across the province was 78.31%, with the highest infestation rate observed in Datong (95.44%), followed by Shuozhou (91.78%), and the lowest infestation rate was observed in Changzhi (64.22%); the fly infestation rate in Datong significantly differed from that in Lyuliang and the other five cities (F=2.954, P<0.05). The average mosquito infestation rate in the rural households across the province was 12.86%, with the highest infestation rate observed in Jinzhong (23.44%), followed by Taiyuan (20.58%) and Shuozhou (20.44%), and the lowest rate was observed in Xinzhou (6.44%); there was a significant difference in mosquito infestation rate between the areas with a relatively high infestation rate (Jinzhong, Taiyuan, and Shuozhou) and the areas with a relatively low infestation rate (Xinzhou, Lyuliang, Changzhi, and Jincheng) (F=2.519, P=0.034). The average cockroach infestation rate in the rural households across the province was 2.19%, with the highest infestation rate observed in Taiyuan (6.83%), followed by Datong (2.67%) and Xinzhou (2.67%), and the lowest infestation rate was observed in Yuncheng (0.08%); there was a significant difference in cockroach infestation rate between Taiyuan and the other ten cities (F=2.068, P<0.05). Conclusion The infestation of rodents and flies in rural households in Shanxi province is relatively serious, the mosquito infestation is also unnegligible, while the cockroach infestation may be not so significant. It is necessary to refine the residential environment for inhabitants in the rural areas, enhance their awareness of disease prevention, improve their hygienic habits, and strengthen the vector control, prevention, and management, so as to keep vector-mediated diseases from spreading.

Objective To observe the effect of anti-tumor peptide from Musca domestica larvae on the nucleus, the mitochondrial membrane potential and apoptosis protein cysteinyl aspartic proteinase-3 (caspase-3), and apoptosis of K562 cells. Methods Hoechst33258 fluorescent staining was used to observe the fluorescence intensity under a fluorescence microscope. The peak 5 and 8 components from M. domestica larvae were incubated with the K562 cells and the fluorescence intensity of the K562 cell nuclei was detected. The fluorescent probe rhodamine 123 was used to label the cells, which were observed under LSCM (laser scanning confocal microscope, LSCM) for the intracellular fluorescence intensity of the dye that reflected the mitochondrial membrane potential. And caspase-3 immuosorbent test kit and microplate were used to detect the enzyme activity of caspase-3 in K562 cells. Results It was found that the peak 5 and 8 components from M. domestica larvae, after incubation with the K562 cells, increased the fluorescence intensity of some K562 nuclei, suggesting the occurrence of apoptosis of K562 cells. The fluorescence intensity of the K562 cells incubated with the peak 5 and 8 components from M. domestica larvae and labeled with rhodamine 123 was significantly lower than that of the cells in the control group (t₁=21.30, t₂=196.23, P<0.05), which indicated that the anti-tumor peptide was able to reduce the mitochondrial membrane potential of K562 cells. Also, the content of caspase-3 in the cells in the test group was significantly higher than that in the cells in the control group(t₁=146.92, t₂= 189.56, P<0.05), which suggested that the antitumor peptide could contribute to apoptosis of the K562 cells. Conclusion The anti-tumor peptides in peak 5 and 8 components can damage the cell nucleus, leading to apoptosis of K562 by reducing the mitochondrial membrane potential, activating the caspase-3, and interfering with the physiological function of the cells.

Objective To investigate the effect of Musca domestica larva antimicrobial peptides on the cell membrane of tumor cells K562. Methods Antimicrobial peptides of M. domestica larvae with inhibition activity to K562 were sieved, through some processes that induced by acupuncture with Escherichia coli induction, isolated and purified by trituration, centrifuga1ization, solid phase extraction (SPE) and reversed-phase high-performance liquid chromatography (RP-HPLC), detected activity by MTT colorimetric method and observed light microscope. After treatment with different concentrations of peaks 5 and 8, the viability, morphological changes, morphological changes, membrane fluorescein leakage and destruction of K562 cells were detected by trypan blue excluding test, optical microscope and fluorescence microscope, spectrofluorophotometer, laser confocal microscope (LSCM), respectively. Results Low concentrations (＜50 μ g/ml) of M. domestica antimicrobial peptides resulted in intact viability, little change of cellular structure, a little of fluorescein leakage [(18.95±0.05)-(22.49±0.68)] and few destruction in K562 cells; however, high concentrations (≥50 μg/ml) of M. domestica antimicrobial peptides induced lower viability, cellular form change increased gradually, a great deal of fluoresceinleakage [(62.77±4.08)-(70.81±0.18)], even macromolecular fluorescent element Dextran-FITC could leak through. Conclusion There is a concentration threshold of M. domestica larvae antimicrobial peptides on K562 cell membrane. Low concentrations of M. domestica larvae antimicrobial peptides can cause the membrane leakage increasing of cell membrane, high concentrations can lead to severe damage of cell membrane, respectively. The antimicrobial peptides inhibit the growth of K562 cells through directly killing the cells, and the mechanism is that firstly damage the membrane function, then may expand the holes or inhibit the growth by other ways after entering the cells.

Objective To identify the relationship between mosquito density and meteorological parameters for selection of appropriate predicting factors for the change of mosquito density in Yuncheng, Shanxi. Methods Spearman's rank correlation was used in the analysis of the correlation between meteorological parameters and mosquito density per month from 2007 to 2009. Stepwise regression analysis was performed to model the mosquito density change regarding meteorological parameters. Results Single wave was observed in the mosquito seasonal succession curve, indicating that mosquitoes arose early in July, reached a peak in August, and disappeared in October. It was found that mosquito density was correlated with temperature and atmospheric pressure other than sunshine time and relative humidity. Stepwise regression analysis showed that ap⁰² and ap1 could be used for predicting mosquito density, though ap1 was more practical. Ap⁰² reflected the average atmospheric pressure of the present month as well as the last two months, and ap¹ indicated the atmospheric pressure in the last month. Conclusion Since mosquito density was correlated with meteorological parameters, its change could be predicted by an atmospheric pressure fitting model.

Objective To assess the effects of antimicrobial peptides of Tenebrio molitor Linnaeus on K562 cells, and to compare the inhibitory effects of these peptides and of hydroxyurea on K562 cell proliferation. Methods A flow cytometry was employed to identify the anti-K562 effects of molitor antimicrobial peptides. Five parallel concentrations of the two agents were set up for comparison, and their K562 inhibition rates at different concentrations were determined using the MTT colorimetric assay. The regression equation and IC₅₀ were computed using the SPSS software based on the relations between the concentration and inhibition rates. Results The proportion of cells in G₀/G₁ and G₂/M phase increased, and that of cells in S phase decreased. Statistical differences were only noticed by comparing cells in G₀/G₁ and S phases and the control group (P＜0.01), indicating that antibacterial peptides inhibited DNA synthesis in S phase by G₀/G₁ phase arrest. The IC₅₀ of antibacterial peptides and hydroxyurea were 29.98 and 3644.45 μg/ml, respectively. Conclusion The anti-K562 activity of antibacterial peptides, a result of cell cycle impairment, noticeably outstripped the inhibitory effects of hydroxyurea on K562 cell proliferation. These peptides have a good prospect for practical application in future.

Objective To investigate the density of mosquitoes and their population composition in the ares of Shanxi province where Japanese encephalitis（JE） was highly prevalent. Methods Mosquitoes were collected by light trap in pig pens, lakesides and other enviranments. Results It was found that the mosquito density at Wuxing lakeside in Yongji was 2000.0 each trap night, 1352.0 in Chengbei district of Yongji city, more than 500 in Dingxiang county and in the Sushui riverside in Yongji and 100-500 in Linyi county(in Sep. 2006 and in Aug. 2007), Wutai county, Taiyuan city, Changzhi city, the Shengtian lakeside in Ruicheng and Yangquan city, with a density of less than 100 in Ruicheng, Linyi county (in Aug. 2006) and the Sushui riverside in Linyi. Culex tritaeniorhynchus accounted for 77.7 percent of all the mosquitoes collected from pens for livestock in Linyi (in Aug. 2007), however Ruicheng, Linyi county ( in Sep. 2006), Yongji city see a lower percentage in terms of the species. In terms of the density of Cx. pipiens pallens in the sites where the samples were collected, the suburbs were ranked at the top of the list, accounting for 100 percent, followed by Wutai county and Dingxiang county. There were fewer species of mosquetoes in other sites, with Aedes vexans and Ae. dorsalis as the major species. As far as the samples collected from lakesides and riversides were concerned, Cx. tritaeniorhynchus was most heavily populated in Shengtian lakeside in Ruicheng, accouting for 94.4 percent, with Cx. pipiens pallens having a highest in Wuxing lakeside and Sushui riverside in Yongji, being over 99.0%. Conclusion In view of the high mosquito density,  Mosquitoe control in pens for livestock and other water-rich areas should be strengthened. Anti?mosquito publicity and promotion of mosquito control infrastructure are to be reinforced in Shengtian Lake scenic spot.

【Abstract】 Objective To isolate and purify the antimicrobial peptides with anti-tumor cell K562 activity from the Tenebrio molitor Linnaeus larvae. Methods Antimicrobial peptides of Tenebrio molitor L.larvae induced by ultrasonic waves were isolated and purified by trituration，centrifuga1ization，solid phase extraction (SPE) and reversed-phase high-performance liquid chromatography (RP?HPLC). Then the antimicrobial peptides with anti-K562 activity were sieved by MTT colorimetric method and light microscope observation. Results Supernatant eluted with 10%, 30%, 80% acetonitrile (ACN) in aqueous solution by solid phase extraction, of which, only 80% was active (P＜0.01). Five anti-tumor peaks appeared after purification by RP-HPLC, which all had strong activity (P＜0.01). Only 9 and 4 peaks could initially identified as antimicrobial peptides, the others still need to be proved. Conclusion There are antimicrobial peptides and anti-ba

【Abstract】 Objective To observe the injury of the antimicrobial peptides with anti-Toxoplasma activity isolated from housefly larvae on the DNA of T.gondii tachyzoites. Methods The antimicrobial peptides of housefly larvae were induced largely by infection and injury, which were isolated and purified by trituration, centrifugalization and column chromatography. Then the antimicrobial peptides with anti-Toxoplasma activity were sieved by methyl thiazolyl tetrazolium colorimetric method and haemacytometry. The DNA contents of T.gondii tachyzoites were detected by flow cytometry （FCM）.  Results From the bar chart of DNA contents, it showed that the difference of distribution between the control group and the experimental group, and tachyzoites in the experimental group were fewer than that in the control group. The tachyzoites in M1 phase were fewer than that in M2 phase in the control group, but the condition was on the contrary in the antimicrobial peptide group. Furthermore, the peak in the M1 stage had an obvious antedisplacement.  Conclusion The antimicrobial peptide isolated from housefly larvae could kill T.gondii by inhibiting the synthesis of DNA.