[Absorption mechanism of dragon's blood phenolic extracts in Caco-2 cells].

The purpose of this study was to study the absorption characteristics of eight main components from dragon's blood phenolic extracts in Caco-2 cells based on the humancolon cancer cell Caco-2 model, and to clarify the oral absorption mechanism of such phenolic extracts. UPLC-MS/MS was used in this study to determine the content of 8 active ingredients including thevetiaflavone, 7,4'-dihydroxyflavone, 7,4'-dihydroxy-5-methoxyhomoisoflavanone, 7,4'-dihydroxyhomoisoflavanone, loureirin C, loureirin A, loureirin B and pterostilbene from dragon's blood phenolic extracts, and Caco-2 cells were used to investigate the effects of incubation time, concentration, temperature, P-gp inhibitor, MRP inhibitor, OCTN1 inhibitor and OCTN2 inhibitor on the absorption of each component. In addition, the transport experiment was conducted to measure the apparent permeability coefficient P_(app) and transport rate of the eight main components to predict the oral absorption mechanism of dragon's blood phenolic extracts. The experimental results showed that the cell uptake of the eight main components in dragon's blood phenolic extracts was time-dependent and concentration dependent, and the uptake of each component did not need to consume energy, which was consistent with the passive diffusion process. P-gp inhibitor, MRP inhibitor and OCTN1 inhibitor had no effect on the cell uptake of each component, only the addition of OCTN2 inhibitor significantly reduced the uptake of pterostilbene(P<0.05). In the transport results, the ER values of the outflow rates of the eight components were all less than 1.5. The above results show that the absorption mechanism of the eight components in Draconis resina phenolic extract may be passive diffusion, and pterostilbene may be the substrate of OCTN2.

[Spatial - temporal clustering analysis of schistosomiasis transmission risk in Yunnan Province from 2004 to 2015].

OBJECTIVE: To explore the spatial-temporal clustering distribution of schistosomiasis transmission risk in Yunnan Province from 2004 to 2015, so as to provide scientific evidence for the future schistosomiasis control and consolidation of the control achievements. METHODS: All data pertaining to endemic situation of human and bovine schistosomiasis and snail survey at a township level in Yunnan Province from 2004 to 2015 were collected. A descriptive epidemiological method and Joinpoint model were used to describe the changing trends of Schistosoma japonicum infections in humans, bovine and snails, and the hotspots and clusters of schistosomiasis transmission risk were identified using spatial autocorrelation analysis, hotspots analysis and retrospective space-time scan statistic in Yunnan Province from 2004 to 2015. RESULTS: The prevalence of S. japonicum infections appeared a continuous decline in humans, bovine and snails in Yunnan Province from 2004 to 2015, and the estimated number of schistosomiasis cases reduced from 43 056 in 2004 to 756 in 2015, with a decline rate of 98.24%. There were no acute cases since 2008 and no infected snails since 2014 in Yunnan Province. There were significant differences in the changing trends of human and bovine S. japonicum infections in Yunnan Province between 2012 and 2015 and between 2013 and 2015, respectively using the Joinpoint model (P < 0.05). In addition, there was a spatial autocorrelation in human S. japonicum infections in Yunnan Province from 2004 to 2013 (P < 0.01), and the hotspots areas for human S. japonicum infections were mainly distributed in some townships from Dali City, Weishan County and Eryuan County. Retrospective spatial-temporal scanning revealed that S. japonicum human, bovine and snail infections were clustered in 23, 15, 4 townships from Dali City, Weishan County, Eryuan County, Nanjian County and Heqing County, respectively, with relative risks of 6.25 to 28.75 (P < 0.01), which was almost consistent with the cluster areas detected by hotspots analysis. CONCLUSIONS: The endemic situation of schistosomiasis significantly reduced in Yunnan Province from 2004 to 2015; however, there is still a risk of schistosomiasis transmission. The monitoring and control of schistosomiasis should be intensified in the future in Yunnan Province.

[Capability building and professional staff of schistosomiasis control institutions in Yunnan Province: a cross-sectional survey].

To understand the current status of professional staff and capacity building among schistosomiasis control institutions in Yunnan Province, the data pertaining to the current status of professional staff and capacity building were captured from the schistosomiasis control institutions at all levels in Yunnan Province. There were 20 schistosomiasis control institutions at a level of above county in Yunnan Province, with 411 employees, and there were 11 institutions with an independent legal personality, with a mean building area of 69.83 m2 per capita. Among all institutions, the number of posts was 382, and the actual number of employees was 360, with 22 job vacancies. The mean age of professional staff was 41.6 years at a province level, 44.1 years at a city level and 42.4 years at a county level, and there were no professionals at ages of < 30 years in city-level institutions. Of all professionals, there were 45.76% with a college degree or below, and 54.26% with a bachelor degree or higher, and 16.55%, 24.57% and 39.90% had senior, moderate and primary professional titles, with mean ages of 49.10, 44.37 years and 38.36 years, respectively. The results of the cross-sectional study demonstrate that there are problems of job vacancy, population aging and low education levels in schistosomiasis control institutions in Yunnan Province. Therefore, the capability building and professional quality should be further improved in schistosomiasis control institutions to meet the requirements of schistosomiasis control activities in Yunnan Province.

[Construction and operation of schistosomiasis diagnosis reference (network) laboratory in Yunnan Province].

A three-level (provincial, municipal and county levels) schistosomiasis diagnosis network platform had been created in Yunnan Province, and assessment of laboratory quality-control samples and field evaluation of nucleic acid diagnostic techniques and immunodiagnostic reagents had been performed. This paper described the review process of the schistosomiasis diagnosis network laboratory and the operation of schistosomiasis diagnosis network laboratory and analyzed the problems of the schistosomiasis diagnosis network laboratory in Yunnan Province. The establishment of the schistosomiasis diagnosis reference (network) laboratory will provide a strong support for schistosomiasis control in Yunnan Province in the new era.

[Risk assessment of schistosomiasis transmission in Chuxiong City of Yunnan Province].

OBJECTIVE: To evaluate the potential risk of schistosomiasis transmission so as to provide the evidence for formulating the control strategy. METHODS: Two villages were selected as the investigated sites in Chuxiong City and the risk of schistosomiasis transmission was evaluated by reviewing the data of schistosomiasis epidemic situation and prevention and control work, and carrying out the field survey for Oncomelania hupensis snail status, wild faeces, and schistosome infection of the population from 2015 to 2017. RESULTS: There was 1.49 hm2 area of snail habitats, with an average density of 0.54 snails/0.1 m2. The occurrence rate of frames with snails was 5.41%. No schistosome-infected snails were found. The positive rate of schistosomiasis serological tests of the residents was 3.36%, but the stool examination positive cases were not found. A total of 58 wild faeces samples were collected but no schistosome infested cases were found. The risk levels of schistosomiasis transmission in both villages were Grade III. CONCLUSIONS: Although Chuxiong City has been in a low risk state of schistosomiasis transmission, the density of snails is still high, and there is a risk of infection source importation. In the future, the infection source control and snail control should be strengthened.

[Oncomelania hupensis status in national schistosomiasis surveillance sites of Yunnan Province from 2015 to 2017].

OBJECTIVE: To master the Oncomelania hupensis distribution and infection status in the national schistosomiasis surveillance sites of Yunnan Province, so as to provide the evidence for making the control and prevention measures. METHODS: The data of O. hupensis surveillance in the 18 national surveillance sites of Yunnan Province from 2015 to 2017 were collected and analyzed with the descriptive analysis method according to the national schistosomiasis surveillance programme. RESULTS: The total surveillance area was 5 710.94 hm2, the area with O. hupensis snails was 205.69 hm2. The number of surveillance frames was 2 094 553, the occurrence rate of frames with snails was 0.62%, and the density of living snails was 0.025 4 snails/0.1 m2. In the schistosomiasis epidemic controlled areas, the area with snails, the occurrence rate of frames with snails and the density of living snails were all the highest. The snail concentrated distribution areas were the small reservoir, bottomland, paddy field, ditch, and dry land, and the snails mainly distributed in the rice, dry crop, weed and wood vegetation. The number of frames with snails, occurrence rate of frames with snails, total number of snails, number of living snails, and repetition areas with snails presented increasing trends, and however, no schistosome-infected snails were found during the three years. CONCLUSIONS: The O. hupensis snail status is obviously serious in the national schistosomiasis surveillance sites of Yunnan Province. The comprehensive snail control measures should continue to be strengthened, so as to effectively control the spread of the snails and reduce the risk of schistosomiasis outbreaks.

[Analysis of schistosomiasis endemic status of national surveillance sites in Yunnan Province, 2016].

OBJECTIVE: To master the prevalence status of schistosomiasis in Yunnan Province in 2016, so as to provide the evidence for formulating the control strategy and intervention measures. METHODS: The schistosomiasis heavy-endemic villages were selected from each of 18 endemic counties as the survey sites. Then, the serological and etiological tests were carried out in the local residents and floating population, and the infection status of the livestock, field feces and Oncomelania hupensis snails were surveyed. RESULTS: The serum positive rate of schistosomiasis of local residents was 8.78% and the serum positive rate was 2.26% of floating population. No schistosome eggs were found in the stool examinations in the population. The area with snails was 80.054 6 hm2 in 2016 with an increasing rate of 45.47% compared to that in 2015. The average density of living snails was 0.031 7/0.1 m2. No schistosome-infected snails were found for the last four years and no new area with snails was found for the last three years. No positive livestock or feces were found. CONCLUSIONS: The schistosomiasis epidemic situation is stabilized in Yunnan Province in 2016. However, the area with snails and the number of living snails are increasing, and therefore, the schistosomiasis epidemic risk still exists. So, the comprehensive control measures should be strengthened continuously.