OBJECTIVETo use a mathematical model and computer simulation to study transmission dynamics and control of schistosomiasis in mountainous regions of Sichuan.

METHODSBased on studies of schistosomiasis japonica transmission in 20 villages in mountainous regions of Sichuan, a mathematical model was developed to characterize the impact of local environmental factors on transmission intensity. The model integrated site-specific factors and was calibrated to field epidemiological data from 3 subset villages. The dichotomic method was then used to predict different control measures.

RESULTSThe study showed high variations in prevalence of infection and infection intensity across villages, ranging between 3%-73%, 0.1-100 epg (eggs per gram stool), respectively. Important factors including occupation of local residents, exposure to contaminated water, microclimatic characteristics were integrated in the model. The predictions of dichotomic models showed that continuing chemotherapy (coverage between 50%-60%) could reduce infection intensities to 30%-80%, but could not change local transmission potential; therefore, the termination of chemotherapy would be followed by bouncing back of transmission. Sustaining targeted environmental interventions through snail and parasite oval control at certain coverage (30%-50%, respectively) could reduce the transmission to relatively stable levels. The model predictions showed that an integrated control (e.g., including both chemotherapy and environmental interventions) could suppress the transmission to an undetectable level even interruption of transmission between 5-10 years.

CONCLUSIONThe study demonstrated the feasibility of using a dynamic model, calibrated to local data, to gain insights into complicated processes underlying the transmission and informing site-specific control strategies.

Adolescent ; Adult ; Animals ; Child ; Child, Preschool ; China ; Environment ; Humans ; Middle Aged ; Models, Theoretical ; Schistosoma japonicum ; Schistosomiasis japonica ; epidemiology ; prevention & control ; transmission ; Snails ; parasitology

OBJECTIVETo study the present situations of lung cancer in Wuhan and to explore the relationship between the potential years of life lost of lung cancer and air pollution, especially vehicle emissions.

METHODSData gathered between 1986 and 1995 in Wuhan city, including air pollution and tobacco production and data on lung cancer between 1991 and 2000 were collected extensively. Simple Correlation and Grey Relational Analysis were used to analyze the relationship of them.

RESULTSThere was a ascending tendency in variance of oxides of nitrogen (NOx). The degree of grey incidence (DGI) between the concentration of air pollutants and the male's or female's potential years of life lost of lung cancer (PYLL) were calculated respectively. In males, the values of DGI were 0.6702, 0.7071, 0.6199 on sulfur dioxide (SO2), NOx, total suspensions (TSP) respectively. In females,the values of DGI were 0.6188, 0.8555, 0.5842 according to the same order as listed above. Significant positive correlation was found between the concentration of NOx and with lung cancer in both males and females by spearman correlation test (rmale = 0.63523, P = 0.0484; rfemale = 0.76396, P = 0.0101).

CONCLUSIONWith the fast growing speed of the quantity of vehicles, pollution of vehicle emission-caused air pollution posed an important risk factor for lung cancer, despite the fact that tobacco smoking still played the leading role.

Air Pollution ; adverse effects ; China ; Female ; Humans ; Lung Neoplasms ; mortality ; Male ; Nitrogen Oxides ; analysis ; Sulfur Dioxide ; analysis ; Vehicle Emissions ; analysis

Objectve: To investigate the feasibility of establishing xenografted leukemia model by zebrafish, so as to provide the more direct model in vitro and experimental evidence for study of acute myeloid leukemia and screening of the drugs for targeting therapy.

METHODSAcute myeloid leukemia cell line KG-1a was labeled with red fluorescent dye-MitoRed, then the labeled cells were injected into the yolk sac of zebrafish embryos. Morphological observation, cell count and histopathological detection were used to analyse the infiltration and metastasis of KG-1a cells in zebrafish.

RESULTSKG1a cells could proliferate and gradually spread to the entire abdominal cavity of the zebrafish after KG-1a cells were injected into the yolk sac during 1-7, the results of cell counting in vitro also proved a significant proliferation of KG-1a cells in zebrafish, suggesting that the implanted leukemia stem cells could survive, proliferate and spread in zebrafish. Further study showed that the implanted cells could be transfered to the liver of zebrafish, these cells displayed the signature of KG-1a cells by hematoxylin-eosin(HE) staining.

CONCLUSIONSHuman acute myeloid leukemia cells KG1a can survive, proliferate and migrate in zebrafish, suggesting xenografted leukemia model of zebrafish has been successfully established. This model may be benefitcial for the study of acute myeloid leukemia and the screening of the drugs for targeting therapy of acute myeloid leukemia.

The pathological processes of Alzheimer's disease and type 2 diabetes mellitus have been demonstrated to be linked together. Both PDE9 inhibitors and PPAR agonists such as rosiglitazone exhibited remarkable preclinical and clinical treatment effects for these two diseases. In this study, a series of PDE9 inhibitors combining the pharmacophore of rosiglitazone were discovered. All the compounds possessed remarkable affinities towards PDE9 and four of them have the IC values <5 nmol/L. In addition, these four compounds showed low cell toxicity in human SH-SY5Y neuroblastoma cells. Compound , the most effective one, gave the IC of 1.1 nmol/L towards PDE9, which is significantly better than the reference compounds PF-04447943 and BAY 73-6691. The analysis of putative binding patterns and binding free energy of the designed compounds with PDE9 may explain the structure-activity relationships and provide evidence for further structural modifications.

OBJECTIVETo evaluate the effect of snail control through soil pasting mixed with niclosamide.

METHODSFour sites were selected in different epidemic areas in Sichuan province. Soil pasting mixed with niclosamide was carried on, and the dosage was 0 g/m2, 4 g/m2, 6 g/m2, 8 g/m2 and 10 g/m2 respectively. The mortality rate of snail and the density of snail were observed after 7, 15, 30, 90 and 180 days.

RESULTSThe mortality rate of snail was more than 43.3% in blank group after 30 days. The mortality rate of snail was from 75.3% to 100.0% at 4 g/m2 group after 30 days. The mortality rate of snail in 4 g/m2 group was significantly higher than that in the blank group (chi2 = 31.27, P < 0.05). There was no significant difference in the mortality rate of snail among all study groups (chi2 = 1.07, P > 0.05). The decrease rate of snail density was more than 90%. The mortality rate of snail was about 30% higher in Chantu group than Qutu group. The unit cost of Pasting-Mixing Drug with Soil was from 5 to 7 times of spray method, but the total cost was similar for the. two methods at the endpoint of the snail control.

CONCLUSIONThe effect of soil pasting mixed with niclosamide is good, and the dosage of 4-6 g/m2 is suggested in snail control.

Animals ; Molluscacides ; Niclosamide ; Pest Control ; Schistosomiasis ; epidemiology ; prevention & control ; Snails ; Soil

Objective To identify the epidemic characteristics and risk factors of an emerging infectious disease-severe fever with thrombocytopenia syndrome (SFTS) in Hubei province.Methods Active surveillance program on SFTS was set up in monitoring sites-hospitals,at the township level or above,in Suizhou,Huanggang and Wuhan from January to December,2010.Specific surveillance program on SFTS was launched across the province in hospitals above the county level.Cases that matched the definition of surveillance case were identified and reported to Centers for Disease Control and Prevention (CDCs).Cases were interviewed and their blood samples collected and detected using PCR and virus isolation.We also conducted serum antibody surveys among healthy population and livestock and surveillance on vector ticks in those high-epidemic areas.Results 188 cases that matched the definition of surveillance case and 21 deaths were reported in 11 cities,32 countries and 100 towns in 2010,with an incidence rate of 0.33/106.The fatality rate was 11.2％.Data showed that the patients were from hilly areas at the altitude elevated between 28-940 meters.The epidemic period was between April and December with the peak from May to September.The youngest case was an 11-year old,while the eldest was 81 with median age as 56-year old.95.3 ％ of the patients were farmers.All Patients did not have the history of traveling,two weeks before the onset of SFTS.93.6％ of the patients engaged in different kind of work which was associated with agriculture.52.8％ of the patients had been exposed to ticks.22.0％ of the patients had been bitten by ticks.Skin injury was found in 64.2％ of the patients.Samples from 129 cases (68.6％) were collected and detected,with 67.4％ of them (87 cases) showed positive by Real time-PCR for SFTS virus.An elevation in antibody titer by a factor of four or evidence of sero-conversion was observed in 11 patients; SFTS virus was isolated from 2 patients.The total antibody positive rates were 3.8％,55.0％ (6/11 ),36.7％ (2/3) and 80.0％ (4/5) respectively in healthy population,dogs,sheep and cows.Ticks from grass,cattle and sheep were detected positive by Real time-PCR.Conclusion Most cases of SFTS in Hubei were infected by SFTS virus,and cases of livestock were infected by SFTS virus.Ticks might serve as an important vector.Skin injury,exposure to tick bites seemed to be the risk factors.

OBJECTIVETo observe the effect of the modified artificial esophagus on postoperative stenosis in dogs.

METHODSThe models of defected esophagus were established in dogs. The double-layered membrane tube (modifying type) was implanted in the test group (n = 10) and the esophageal stent was further inserted when the stenosis occurred. The single pattern tube (original type) was transplanted to the control group (n = 30). The dilation treatment was performed to relieve the postoperative stenosis; alternatively, the esophageal stent was implanted in the unsuccessful dogs.

RESULTSThe average artificial esophagus removal time was 19.10 days in the test group, which was significantly lower than 39.07 days in the control group (t = 15.6, P = 0.000). No obstruction after removal was observed in the experimental group. The incidence of postoperative stenosis had no significant difference between these two groups.

CONCLUSIONThe double-layered membrane tube can make the tube removal safer by shortening the removal time.

Animals ; Artificial Organs ; Dogs ; Esophageal Stenosis ; prevention & control ; Esophagectomy ; Esophagus ; transplantation ; Female ; Male ; Postoperative Complications ; prevention & control ; Random Allocation

OBJECTIVETo study the optimal surgical resection length for esophageal carcinoma.

METHODSSpecimens of seventy patients with esophageal squamous cell carcinoma resected and collected in our hospital were made into pathologic giant sections. Direct intramural infiltration, multicentric carcinogenic lesion and leaping metastasis were observed in the large slice by microscope. The actual length during the operation was calculated by the ratio of shrinkage.

RESULTSDirect intramural infiltration was found in 51 (72.9%) patients, 39 proximal and 36 distal to the tumor. The mean length of direct intramural infiltration was 0.9 +/- 0.8 cm (4.0 cm maximum) proximally and 0.5 +/- 0.3 cm (2.0 cm maximum) distally. Multicentric carcinogenic lesion was found in 11 (15.7%) patients, 5 proximally, 8 distally and 2 on both sides. Proximal to the tumor, the mean distance between the multicentric carcinogenic lesion and the main lesion plus the length of the multiple carcinogenic lesion was 3.2 +/- 1.5 cm (4.7 cm maximum). Distal to the tumor, it was 3.6 +/- 2.4 cm (9.1 cm maximum). Leaping metastasis was found in 9 (12.9%) patients, 7 proximally and 4 distally. The mean distance between the leaping metastasis and the main lesion plus the length of the leaping metastatic lesion was 1.9 +/- 0.6 cm (2.9 cm maximum) proximally and 1.4 +/- 1.0 cm (2.7 cm in maximum) distally.

CONCLUSIONThe optimal surgical resection length for esophageal carcinoma should be at least 5 cm proximal to the tumor and total length on the distal side.

Esophageal Neoplasms ; pathology ; surgery ; Female ; Humans ; Male ; Neoplasm Invasiveness

BACKGROUNDResearchers have recently demonstrated that thrombospondin-1 (TSP-1) has an important function in regulating neovascularization. Whether it inhibits or accelerates neovascularization, however, is still controversial. We found few reports about the correlation between TSP-1 and vascularization in mucoepidermoid carcinoma. In this research, the distribution and expression of TSP-1 in mucoepidermoid carcinoma were investigated. We also analyzed (1) the correlation between the expression of TSP-1 and microvessel density (MVD), as an indicator of neovascularization activity, and (2) the effect of TSP-1 on neovascularization and tumor growth in the subcutaneous xenotransplanted model of mucoepidermoid carcinoma.

METHOD(1) The sites and intensity of expression of TSP-1 and the MVD were analyzed in 45 cases of mucoepidermoid carcinoma after surgery by the method of streptavidin-peroxidase (SP) immunohistochemistry; and (2) recombinant human thrombospondin-1 (rhTSP-1) was injected twice a week for five consecutive weeks around the tumor in the subcutaneous xenotransplanted tumor model of mucoepidermoid carcinoma in nude mice. Each week, the tumor size was measured, in order to draw the growth curve of the xenotransplanted tumor model of mucoepidermoid carcinoma, and MVD was measured.

RESULTS(1) The positive expression of TSP-1 protein was 57.78% (26/45). Most positive staining for TSP-1 was found in the cytoplasm of the cancer cells, while some staining occurred in the extracellular matrix. The mean MVD in 45 cases of mucoepidermoid carcinoma was 58.17 +/- 19.77 per 100 visual fields. Tumors with a high expression of TSP-1 showed a low MVD value, and the TSP-1 immunocompetence and microvessel density showed a significant negative correlation (r(s) = -0.947, P < 0.001). (2) The xenotransplanted tumors with the injection doses of 1.25, 0.75 and 0.25 microg/ml respectively were 36.97%, 53.36% and 73.61% of the size of the control group ((451 +/- 92), (651 +/- 113), (898 +/- 86) and (1220 +/- 157) mm(3) respectively, F = 53.167, P < 0.001), and their weights were respectively 35.14%, 51.35% and 70.27% of the control group ((1.3 +/- 0.5), (1.9 +/- 0.5), (2.6 +/- 0.3), and (3.7 +/- 0.7) g respectively, F = 62.669, P < 0.001). Their MVDs were 25.00%, 45.93%, and 72.20% respectively of the control group and concentration dependent (15.43 +/- 3.45, 28.35 +/- 4.24, 44.57 +/- 3.35 and 61.73 +/- 5.43 per 100 visual fields respectively, F = 54.582, P < 0.001).

CONCLUSIONSThe TSP-1 has a higher expression in mucoepidermoid carcinoma and the expression has a significant negative correlation with neovascularization. The TSP-1 inhibits neovascularization and tumor growth, and it might be a new biological therapy for treatment of patients with mucoepidermoid carcinoma.

Adult ; Aged ; Animals ; Carcinoma, Mucoepidermoid ; blood supply ; chemistry ; pathology ; Female ; Humans ; Male ; Mice ; Middle Aged ; Neoplasm Transplantation ; Neovascularization, Pathologic ; pathology ; Recombinant Proteins ; pharmacology ; Thrombospondin 1 ; analysis ; pharmacology ; Transplantation, Heterologous

Objective To identify the risk factors for reported sudden rise of measles incidence in November,2011,in some areas of Hubei province.Methods We analyzed all measles patients reported in the measles surveillance system from November 2011 to February 2012 in two prefectures with highest attack rates and their vaccination history by reviewing vaccination records.We interviewed patients' parents by telephone to obtain the history of visiting health care within 7 to 21 days before onset.We also used case-crossover study to estimate the relative risk (RR) of hospital acquired infection and to compare the exposure to health care between 7-21 days before onset to 37-51 days before onset among measles patients.Results Totally 140 patients were reported in the two prefectures.Reported measles incidence rates among the population aged ＜8 m (69/100 000) and 8 m to 17 m (72/100 000) were higher than other age groups (rang from 0 to 5.8 per 100 000).Among the population aged 8 m to 17 m,estimated vaccination coverage was lower than 75％,and it was lower than 90％ among those aged 18 m to 3 yrs.During 7-21 days before onset,58％(29/50) of the patients had an exposure to health care settings,compared to 14％ (7/50) of patients during 37 to 51 days before onset (MH RR=5.4,95％ confidence interval=2.1-14.0).Conclusion Under the condition of measles vaccination coverage lower than 95％,iatrogenic infection was a risk factor for measles in Hubei.