Objective To analyze the epidemiological characteristics of malaria in Jiangxi Province from 2010 to 2014 and to provide a reference for malaria control in the whole province.Methods Data on malaria cases in Jiangxi Province from 2010 to 2014 were collected through the Disease Reporting Information System of Chinese Center for Disease Control and Prevention and Information System for Parasitic Diseases Control and Prevention.Descriptive epidemiological method was used to analyze the area distribution,time distribution and population distribution of the malaria cases.Results A total of 218 malaria cases were reported from 2010 to 2014 in the province,with an annual mean incidence of 0.097 3/100 000.One dead case was reported with a fatality rate of 0.46％(1/218).Of all 11 prefectures and 100 counties (cities,districts) in Jiangxi,65 counties (cities,districts)reported malaria cases.The top three counties (cities,districts) of malaria cases were Qingshanhu (22),Nanchang (15)and Jinxian (13),totally accounting for 22.94％ (50/218).The cases were reported through the whole year,without obvious seasonal peak.The ratio of male to female was 30.14:1.00.The age of the cases mainly distributed around the ages of 20-＜ 60 years,accounting for 94.49％ (206/218).The peak appeared in 40-＜ 50 years group,accounting for 32.11％ (70/218).The three major occupations of the cases were farmer,worker and migrant worker (131,60.09％).The cases were mainly imported from Africa and Southeast Asia,whose proportion of imported cases was 76.19％ (160/210) and 19.52％ (41/210),respectively.Conclusions The incidence of malaria is stable with a slight increase in Jiangxi Province from 2010 to 2014.Control of imported malaria cases will be the main task in the future.

Rhamnolipid biosurfactant is mainly produced by Pseudomonas aeruginosa that is the opportunistic pathogenic strain and not suitable for future industrial development. In order to develop a relatively safe microbial strain for the production of rhamnolipid biosurfactant, we constructed engineered Escherichia coli strains for rhamnolipid production by expressing different copy numbers of rhamnosyltransferase (rhlAB) gene with the constitutive synthetic promoters of different strengths in E. coli ATCC 8739. We further studied the combinatorial regulation of rhlAB gene and rhaBDAC gene cluster for dTDP-1-rhamnose biosynthesis with different synthetic promoters, and obtained the best engineered strain-E. coli TIB-RAB226. Through the optimization of culture temperature, the titer of rhamnolipd reached 124.3 mg/L, 1.17 fold higher than that under the original condition. Fed-batch fermentation further improved the production of rhamnolipid and the titer reached the highest 209.2 mg/L within 12 h. High performance liquid chromatography-mass spectrometry (LC-MS) analysis showed that there are total 5 mono-rhamnolipid congeners with different nuclear mass ratio and relative abundance. This study laid foundation for heterologous biosynthesis of rhanomilipd.
Bacterial Proteins ; genetics ; Batch Cell Culture Techniques ; Decanoates ; Escherichia coli ; metabolism ; Fermentation ; Glycolipids ; biosynthesis ; Hexosyltransferases ; genetics ; Industrial Microbiology ; methods ; Multigene Family ; Promoter Regions, Genetic ; Pseudomonas aeruginosa ; Rhamnose ; analogs & derivatives ; biosynthesis ; Surface-Active Agents ; metabolism

Objective To understand the capability of parasitic disease diagnosis among professionals from the clinic labora?tory of Class A tertiary hospitals in Jiangxi Province. Methods The teams that took part in the competition were formed from 20 Class A tertiary hospitals,with 2 contestants per team. The competition contents included written examination and skill opera?tion. The written examination involved the life cycle of parasites,immunological basis,detecting techniques,etiological diagno?sis etc.,and the skill operation involved making and dying thin and thick blood smears,making Kato?Katz’s fecal thick smears, as well as microscopic examinations of smears. Results A total of 40 participants took part in the competition. Their total aver?age score was 97.3±22.4 with the pass rate of 15.0%,in which the mean score of theoretical knowledge was 56.6±12.8 with the pass rate of 52.5%,and the mean score of skill operation was 40.8±12.4 with the pass rate of 5.0%. In the written examination, the scoring rate of the life cycle of soil?transmitted helminths was the highest(90.0%),and the rate of the basic knowledge of food?borne parasites was the lowest(31.5%). Both the pass rates of blood smear making and examination were higher than those of Kato?Katz’s thick smears,and the differences were statistically significant( both P<0.05). The detection rates of Plasmodi?um vivax,Plasmodium falciparum,Plasmodium ovale and negative slides of the contestants were 38.8%,45.0%,35.0%and 25.0% respectively. As to the microscopic examination of helminth eggs,the detection rate of Trichuris trichiura egg was the highest(87.5%),and the rate of the Sparganum mansoni egg was the lowest(2.5%). The scores of Kato?Katz’s thick smear making and examination of the contestants from the provincial level hospitals were higher than those from the city level hospitals (both P<0.05),and the score of those from teaching hospitals in Kato?Katz’s thick smear making was higher than that of those from non?teaching hospitals(P < 0.05). Conclusions The technique level of professionals from the clinic laboratory of the Class A tertiary hospitals cannot meet the needs of the diagnosis of parasitic diseases in Jiangxi Province ,which should arouse the attention of the health authorities and hospitals.

Objective To assess the risk of secondary transmission induced by imported malaria in Jiangxi Province，so as to provide the evidence for adjustment of malaria surveillance strategies in the key groups and areas. Methods The Delphi method was used to establish the secondary transmission risk indicator system and the weight of each index was obtained. The data of malaria prevalence，vector distribution and intervention capacity were collected in 100 counties of Jiangxi Province from 2012 to 2015. The transmission potential index（TPI），intervention capacity index（ICI），and malaria risk index（MRI）were calculated for each county. The risk map was drawn with GIS software. Results The top ten counties with highly potential risk indicators were Linchuan District（2.131），Xinzhou District（1.609），Jiujiang County（1.404），Zhanggong District（1.365）， Fengcheng City（1.225），Qingshanhu District（1.184），Yudu County（1.171），Dingnan County（1.018），Xunyang District（1.015）and Zhushan District（1.006）. The high risk areas were mainly distributed in the regions of the capitals of their prefectures and in counties with more floating population. Conclusions There are the risk of the secondary transmission induced by imported malaria in Jiangxi Province. The high risk of the secondary transmission is shown in the areas with more floating population and weaker intervention capacity.

Objective:To understand the status and tendency of coal-burning-borne endemic fluorosis after implementation of prevention and control measures in Jiangxi Province.Methods:According to the requirements of the national "Coal-burning-borne Endemic Fluorosis Monitoring Program", 3 fixed monitoring villages and 5 non-fixed monitoring villages in Luxi, Shangli were selected as monitoring sites every year from 2014 to 2018, respectively, 10 households were selected by simple random method in each village to survey the usage of stove and health behavior related to the consumption of pepper. At the same time, dental fluorosis and urinary fluoride were monitored in children aged 8 - 12 years in fixed monitoring villages.Results:There were significant differences in the utilization rate of improved stoves, the utilization rate of electric cookers and the qualified rate of improved stoves in fixed monitoring villages between each year (χ 2 = 111.70, 83.96, 36.64, P < 0.05), but there was no significant difference in the correct utilization rate of qualified improved stoves(χ 2 = 2.35, P > 0.05). There were significant differences in the utilization rate of improved stoves, the utilization rate of electric cookers, the qualified rate of improved stoves and the correct utilization rate of qualified improved stoves in non-fixed monitoring villages between each year (χ 2 = 132.32, 42.63, 50.03, 15.29, P < 0.05). There was no significant difference in pepper correct drying rates between fixed monitoring villages and non-fixed monitoring villages between each year (χ 2 = 4.068, 3.436, P > 0.05), the rate of pepper correct keeping and washing methods was 100% in monitored villages each year. From 2014 to 2018, the detection rate of dental fluorosis in children aged 8 - 12 years decreased from 17.04% (106/622) to 6.68% (90/1 347), and showed a downward trend year by year (χ 2trend = 72.60, P < 0.01). The annual geometric mean of urinary fluoride of children was 0.77, 0.74, 0.71, 0.74 and 0.72 mg/L, respectively. There was no significant difference among years ( H = 4.142, P > 0.05). Conclusion:Remarkable achievements have been made in the prevention and control of coal-burning-borne endemic fluorosis in Jiangxi Province.

Objective: To determine the spatiotemporal distribution of Schistosoma (S.) japonicum infections in humans, livestock, and Oncomelania (O.) hupensis across the endemic foci of China. Methods: Based on multi-stage continuous downscaling of sentinel monitoring, county-based schistosomiasis surveillance data were captured from the national schistosomiasis surveillance sites of China from 2005 to 2019. The data included S. japonicum infections in humans, livestock, and O. hupensis. The spatiotemporal trends for schistosomiasis were detected using a Joinpoint regression model, with a standard deviational ellipse (SDE) tool, which determined the central tendency and dispersion in the spatial distribution of schistosomiasis. Further, more spatiotemporal clusters of S. japonicum infections in humans, livestock, and O. hupensis were evaluated by the Poisson model. Results: The prevalence of S. japonicum human infections decreased from 2.06% to zero based on data of the national schistosomiasis surveillance sites of China from 2005 to 2019, with a reduction from 9.42% to zero for the prevalence of S. japonicum infections in livestock, and from 0.26% to zero for the prevalence of S. japonicum infections in O. hupensis. Analysis using an SDE tool showed that schistosomiasis-affected regions were reduced yearly from 2005 to 2014 in the endemic provinces of Hunan, Hubei, Jiangxi, and Anhui, as well as in the Poyang and Dongting Lake regions. Poisson model revealed 11 clusters of S. japonicum human infections, six clusters of S. japonicum infections in livestock, and nine clusters of S. japonicum infections in O. hupensis. The clusters of human infection were highly consistent with clusters of S. japonicum infections in livestock and O. hupensis. They were in the 5 provinces of Hunan, Hubei, Jiangxi, Anhui, and Jiangsu, as well as along the middle and lower reaches of the Yangtze River. Humans, livestock, and O. hupensis infections with S. japonicum were mainly concentrated in the north of the Hunan Province, south of the Hubei Province, north of the Jiangxi Province, and southwestern portion of Anhui Province. In the 2 mountainous provinces of Sichuan and Yunnan, human, livestock, and O. hupensis infections with S. japonicum were mainly concentrated in the northwestern portion of the Yunnan Province, the Daliangshan area in the south of Sichuan Province, and the hilly regions in the middle of Sichuan Province. Conclusions: A remarkable decline in the disease prevalence of S. japonicum infection was observed in endemic schistosomiasis in China between 2005 and 2019. However, there remains a long-term risk of transmission in local areas, with the highest-risk areas primarily in Poyang Lake and Dongting Lake regions, requiring to focus on vigilance against the rebound of the epidemic. Development of high-sensitivity detection methods and integrating the transmission links such as human and livestock infection, wild animal infection, and O. hupensis into the surveillance-response system will ensure the elimination of schistosomiasis in China by 2030.

Objective To optimize the culture and fermentation conditions of the Penicillium aurantiocandidum Z12 strain, a fungal strain with molluscicidal actions against Oncomelania hupensis, so as to provide the basis for the research and development of molluscicidal active substances from the P. aurantiocandidum Z12 strain and its fermentation broth and large-scale fermentation. Methods The carbon source, nitrogen source and mineral salts were identified in the optimal culture medium for the P. aurantiocandidum Z12 strain with a single-factor experiment to determine the best fermentation condition for the P. aurantiocandidum Z12 strain. Factors that significantly affected the growth of the P. aurantiocandidum Z12 strain were identified using the Plackett-Burman design, and the best range of each factor was determined using the steepest climb test. Response surface analyses of temperature, pH value, seeding amount and liquid-filling quantity were performed using the Box-Behnken design to create a regression model for fermentation of the P. aurantiocandidum Z12 strain to identify the optimal culture medium. Results Single-factor experiment preliminarily identified the best culture medium and conditions for the P. aurantiocandidum Z12 strain as follows: sucrose as the carbon source at approximately 20 g/L, tryptone as the nitrogen source at approximately 5 g/L, K₂HPO₄ as the mineral salt at approximately 5 g/L, initial pH at approximately 8, temperature at approximately 28 °C, seeding amount at approximately 6%, and liquid-filling quantity at approximately 50 mL/100 mL. Plackett-Burman design showed that factors that significantly affected the growth of the P. aurantiocandidum Z12 strain included temperature (t = −5.28, P < 0.05), seeding amount (t = 5.22, P < 0.05), pH (t = −4.30, P < 0.05) and liquid-filling quantity (t = −4.39, P < 0.05). Steepest climb test showed the highest mycelial growth at pH of 7.5, seeding amount of 8%, and liquid-filling quantity of 40 mL/100 mL, and this condition was selected as the central point of response surface analysis for the subsequent optimization of fermentation conditions. Response surface analyses using the Box-Behnken design showed that the optimal conditions for fermentation of the P. aurantiocandidum Z12 strain included sucrose at 15 g/L, tryptone at 5 g/L, K₂HPO₄ at 5 g/L, temperature at 28.2 °C, pH at 7.5, seeding amount at 10%, and liquid-filling quantity at 35.8 mL/100.0 mL, resulting in 0.132 g yield of the P. aurantiocandidum Z12 strain. Conclusion The optimal culture condition for the P. aurantiocandidum Z12 strain has been identified, and the optimized culture medium and fermentation condition may effectively improve the fermentation yield of the P. aurantiocandidum Z12 strain.