Unsupervised Machine Learning-Based Analysis of Clinical Features, Bone Mineral Density Features and Medical Care Costs of Rotator Cuff Tears.

PURPOSE: We aim to present unsupervised machine learning-based analysis of clinical features, bone mineral density (BMD) features, and medical care costs of Rotator cuff tears (RCT). PATIENTS AND METHODS: Fifty-three patients with RCT were reviewed, the clinical features, BMD features, and medical care costs were collected and analyzed by descriptive statistics. Furtherly, unsupervised machine learning (UML) algorithm was used for dimensionality reduction and cluster analysis of the RCT data. RESULTS: There were 26 males and 27 females. The patients were divided into four subgroups using the UML algorithm. There were significant differences among four subgroups regarding trauma exposure, full-thickness supraspinatus tendon tears, infraspinatus tendon tear, subscapularis tendon tear, BMD distribution, medial row anchors, lateral row anchors, total medical care costs, and consumables costs. We observed the highest frequency of trauma exposure, infraspinatus tendon tear, subscapularis tendon tear, osteoporosis, the highest number of medial row anchors, lateral row anchors, total medical care costs, and consumables costs in subgroup II. CONCLUSION: The unsupervised machine learning-based analysis of RCT can provide clinically meaningful classification, which shows good interpretability and contribute to a better understanding of RCT. The significance of the results is limited due to the small number of samples, a larger follow-up study is needed to confirm the encouraging results.

Postoperative Bone Marrow Lesions (BMLs) Are Associated with Pain Severity in Patients Undergoing Open Wedge High Tibial Osteotomy (OWHTO).

The purpose of the study was to investigate the relationship between postoperative bone marrow lesions (BMLs) and pain severity in patients undergoing open wedge high tibial osteotomy (OWHTO). We reviewed the patients undergoing OWHTO between April 2018 and April 2020. The demographic and clinical data of patients were collected. Clinically, VAS and Knee injury and Osteoarthritis Outcome Score (KOOS) were used to assess pain level and functional outcomes of patients. The MRI Osteoarthritis Knee Score (MOAKS) was used to assess the total BMLs size in medial tibiofemoral (MTF), lateral tibiofemoral (LTF), and patellofemoral (PF) joints. 98 patients were enrolled in the study, including 57 male and 41 female patients. The VAS scores improved significantly from 6.1 ± 0.8 to 1.5 ± 0.9 (p < 0.001), and all subscales of KOOS improved significantly after surgery (p < 0.001). There were no significant differences between the pre- and postoperative total BML size of PF and LTF joints (p > 0.05). We observed significant improvements in the total BML size of MTF joint (p < 0.001). The VAS scores and KOOS pain scores improved better in patients without postoperative MTF joint BMLs (p < 0.001). Postoperative MTF joint BMLs were correlated with postoperative VAS (p < 0.001) and KOOS pain (p < 0.001). Our study demonstrates that MTF joint BMLs improved significantly after OWTHO. We confirmed that the presence of postoperative MTF joint BMLs are strongly associated with pain severity. The greater the improvement in postoperative MTF joint BMLs, the less pain. Our findings provide valuable understandings of OWHTO in the treatment of knee osteoarthritis (KOA) and potential future directions for KOA treatment approaches.

A Novel Application of Unsupervised Machine Learning and Supervised Machine Learning-Derived Radiomics in Anterior Cruciate Ligament Rupture.

PURPOSE: We aim to present an unsupervised machine learning application in anterior cruciate ligament (ACL) rupture and evaluate whether supervised machine learning-derived radiomics features enable prediction of ACL rupture accurately. PATIENTS AND METHODS: Sixty-eight patients were reviewed. Their demographic features were recorded, radiomics features were extracted, and the input dataset was defined as a collection of demographic features and radiomics features. The input dataset was automatically classified by the unsupervised machine learning algorithm. Then, we used a supervised machine learning algorithm to construct a radiomics model. The t-test and least absolute shrinkage and selection operator (LASSO) method were used for feature selection, random forest and support vector machine (SVM) were used as machine learning classifiers. For each model, the sensitivity, specificity, accuracy, and the area under the curve (AUC) of receiver operating characteristic (ROC) curves were calculated to evaluate model performance. RESULTS: In total, 5 demographic features were recorded and 106 radiomics features were extracted. By applying the unsupervised machine learning algorithm, patients were divided into 5 groups. Group 5 had the highest incidence of ACL rupture and left knee involvement. There were significant differences in left knee involvement among the groups. Forty-three radiomics features were extracted using t-test and 7 radiomics features were extracted using LASSO method. We found that the combination of LASSO selection method and random forest classifier has the highest sensitivity, specificity, accuracy, and AUC. The 7 radiomics features extracted by LASSO method were potential predictors for ACL rupture. CONCLUSION: We validated the clinical application of unsupervised machine learning involving ACL rupture. Moreover, we found 7 radiomics features which were potential predictors for ACL rupture. The study indicated that radiomics could be a valuable method in the prediction of ACL rupture.

Three-Portal Approach of Arthroscopy for Anterior Ankle Impingement Syndrome: A Propensity Score-Matched Analysis.

OBJECTIVE: To introduce a 3-portal approach of arthroscopic for anterior ankle impingement syndrome and to compare this method with 2-portal arthroscopy. METHODS: From July 2011 to April 2019, a total of 52 patients (30 females, 22 males) with anterior ankle impingement syndrome underwent surgery with 2-portal approach (anterior medial and anterior lateral approach; N = 26) and modified 3-portal approach (anterior medial, anterior lateral, and an accessory anterior median approach; N = 26) of arthroscopic were recruited retrospectively after we performed a propensity score-matched analysis (PSMA). The mean age at operation time was 44.1 years (range from 22 years to 74 years) and the mean follow-up duration was more than two years (range from 2 years to 9 years). Clinical outcomes of all patients were evaluated according to the range of motion (ROM, dorsal flex angle), the American Orthopaedic Foot and Ankle Society lesser metatarsophalangeal interphalangeal scale (AOFAS), the visual analogue scale (VAS), and the operation time before and after the surgery. RESULTS: During the follow-up period, both two groups indicated significant improvement in these function scores. Clinical assessment showed that for the 2-portal approach of arthroscopic the total average of AOFAS scores were significantly increased from preoperative 59.91 ± 5.281 points to postoperative 76.18 ± 1.471 points (P = 0.02), the VAS scores were significantly decreased from preoperative 7.64 ± 0.924 points to postoperative 4.18 ± 0.982 points (P = 0.04), and the dorsal flex angle was significantly increased from preoperative 12.27° ± 6.467° to postoperative 21.36° ± 3.931° at the last follow-up (P = 0.035). However, for the 3-portal approach of arthroscopic the total average of AOFAS scores were significantly increased from preoperative 48.64 ± 9.646 points to postoperative 79.18 ± 6.555 points (P = 0.015), the VAS scores were significantly decreased from preoperative 7.82 ± 0.751 points to postoperative 2.64 ± 1.629 points (P = 0.01), and the dorsal flex angle was significantly increased from preoperative 13.64° ± 7.775° to postoperative 20.45° ± 6.502° at the last follow-up (P = 0.045). There were no significant differences among the dorsal flex angle, the AOFAS scores, and the VAS scores between the two groups at the last follow-up (P > 0.05). Although the operation time of the 3-portal approach of arthroscopic (74.82 ± 18.395 min) was longer than that of the 2-portal approach of arthroscopic (92.55 ± 27.153 min), the difference was not significant (P > 0.05). CONCLUSION: Both the 2-portal and the 3-portal approach of arthroscopic provides almost the same satisfactory clinical outcomes for anterior ankle impingement syndrome, but we strongly suggest the 3-portal approach of arthroscopic which can supply greater joint contact area to treat advanced impingement syndrome for a good result.

[Influence of acupuncture combined with rehabilitation therapy on limb motor function and serum cAMP and cGMP in patients with hemiplegia of cerebral ischemic stroke].

OBJECTIVE: To evaluate the therapeutic effect of the combined treatment with balance acupuncture therapy and exercise re-learning rehabilitation therapy and the impact on serum cAMP and cGMP in the patients with hemiplegia of cerebral ischemic stroke. METHODS: A total of 90 patients of hemiplegia of cerebral ischemic stroke were randomized into an observation group and a control group, 45 cases in each one. All of the patients in the two groups received health education, diet guidance, routine symptomatic treatment as well as exercise re-learning rehabilitation therapy. Additionally, in the observation group, balance acupuncture therapy was applied, in which, the acupoints on the yang aspect of the human body, on the governor vessel and bladder meridian were adopted in the morning and those on the yin aspect of the human body, on the conception vessel and kidney meridian were stimulated in the afternoon. In the control group, the regular acupuncture was given. In the two groups, both acupuncture and rehabilitation therapies were given 5 days a week, 2 week-treatment as one course and totally 2 courses were required. Separately, before and after treatment, the score of Fugl-Meyer assessment (FMA) and the score of Chinese stroke scale (CSS) were recorded, the levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) detected in serum and the clinical therapeutic effect were evaluated in the two groups. RESULTS: After treatment, FMA score was increased in the patients of either of the groups as compared with that before treatment (P<0.01) and CSS score decreased as compared with that before treatment (P<0.01). After treatment, FMA score in the observation group was higher than that in the control group (P<0.01) and CSS score was lower than the control group (P<0.01). After treatment, the level of serum cAMP of the patients in either of the groups was increased as compared with that before treatment (P<0.01) and that of cGMP decreased as compared with that before treatment (P<0.01). After treatment, the level of cAMP in the observation group was higher than that in the control group (P<0.01) and that of cGMP was lower than the control group (P<0.01). The total effective rate was 93.3% (42/45) in the observation group, better than 73.3% (33/45) in the control group (P<0.01). CONCLUSION: The balance acupuncture therapy combined with exercise re-learning rehabilitation effectively improves the motor function of the affected limb, relieves injury and regulate the levels of serum cAMP and cGMP in the patients with hemiplegia of ischemic stroke.

Baicalin Attenuates Joint Pain and Muscle Dysfunction by Inhibiting Muscular Oxidative Stress in an Experimental Osteoarthritis Rat Model.

Osteoarthritis (OA) is the most common degenerative joint disease, and causes major pain and disability in adults. It has been reported that muscle weakness and inflammation contribute to osteoarthritis development and progression. Oxidative stress plays important roles in muscle dysfunction and inflammation in osteomyelitis. Baicalin, the major active constituent of the isolated root of Scutellarialateriflora Georgi, has been shown to have anti-oxidative and anti-inflammatory effects. In this study, we evaluated the potential effects of baicalin on osteoarthritis. We established experimental osteoarthritis rat model, applied baicalin to the rats, and then explored the potential protective effect of baicalin on osteoarthritis severity, muscle dysfunction, and oxidative stress. Baicalin alleviated severity of OA in rats. Baicalin application attenuated muscle dysfunction in OA rats by increasing citrate synthase activity, myosin heavy chain IIa expression, and decreasing interleukin 6 production. Baicalin decreased muscular reactive oxygen species generation in OA rats. Baicalin inhibited nuclear factor erythroid-derived 2-like 2 expression in OA rats. Baicalin attenuated osteoarthritis in rat by inhibiting oxidative stress.

Risk patterns of subsequent primary cancers following esophagectomy in early-stage thoracic esophageal squamous cell cancer patients.

AIMS AND BACKGROUND: Subsequent primary cancers (SPCs) have been demonstrated to be the major causes of death among patients with thoracic esophageal squamous cell cancer (ESCC) negative for lymph node involvement. We designed this study to investigate clinical characteristics and risk patterns of SPCs following esophagectomy in patients with early-stage thoracic ESCC. METHODS: We retrospectively analyzed clinical factors in 512 patients with early-stage thoracic ESCC collected from 3 independent hospitals over a 10-year interval. RESULTS: The overall standard incidence rate (SIR) of SPCs was 3.84 (95% confidence interval 2.98-4.95). The most common SPCs were head and neck cancers, lung cancer, and stomach cancer. The risk patterns of SPCs varied across organs. A 3-phase risk pattern with a U-shaped curve between 2 rising phases was seen for head and neck cancers, while for the other cancers, the risk patterns all displayed as an approximately linear upward trend. It was further noted that sex, smoking habits, and cancer histories among first-degree relatives were 3 significant independent risk factors in the development of SPCs. CONCLUSIONS: We observed significant associations between early-stage ESCC and SPCs arising from anatomically adjacent sites. The different risk patterns of SPCs indicated that follow-up strategies should be established accordingly in different organs at different times, with particularly close follow-up for head and neck cancers in the first 5 years and beyond 15 years after diagnosis of ESCC.

Platelet-rich plasma in arthroscopic rotator cuff repair: a meta-analysis of randomized controlled trials.

PURPOSE: The purpose of this study was to appraise the retear rate and clinical outcomes of platelet-rich plasma use in patients undergoing arthroscopic full-thickness rotator cuff repair. METHODS: We searched the Cochrane Library, PubMed, and EMBASE databases for randomized controlled trials comparing the outcomes of arthroscopic rotator cuff surgery with or without the use of platelet-rich plasma. Methodological quality was assessed by the Detsky quality scale. When there was no high heterogeneity, we used a fixed-effects model. Dichotomous variables were presented as risk ratios (RRs) with 95% confidence intervals (CIs), and continuous data were measured as mean differences with 95% CIs. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used to assess the quality of evidence for each individual outcome. RESULTS: Eight randomized controlled trials were included, with the sample size ranging from 28 to 88. Overall methodological quality was high. Fixed-effects analysis showed that differences were not significant between the 2 groups in retear rate (RR, 0.94; 95% CI, 0.70 to 1.25; P = .66), Constant score (mean difference, 1.12; 95% CI, -1.38 to 3.61; P = .38), and University of California at Los Angeles (UCLA) score (mean difference, -0.68; 95% CI, -2.00 to 0.65; P = .32). The strength of GRADE evidence was categorized respectively as low for retear, moderate for Constant score, and low for UCLA shoulder score. CONCLUSIONS: Our meta-analysis does not support the use of platelet-rich plasma in the arthroscopic repair of full-thickness rotator cuff tears over repairs without platelet-rich plasma because of similar retear rates and clinical outcomes. LEVEL OF EVIDENCE: Level II, meta-analysis of Level I and II randomized controlled trials.

Percutaneous first annular pulley release for trigger digits: a systematic review and meta-analysis of current evidence.

PURPOSE: To determine the overall success rate and potential influencing factors within the current evidence for percutaneous first annular pulley release. METHODS: We searched PubMed, EMBASE, and the Cochrane Library for all clinical studies of percutaneous release. The rates of successful procedure and complication were extracted and analyzed. We charted the overall success rate on a forest plot with 95% confidence intervals. Data of success rates were analyzed in 5- and 10-year intervals to determine whether the rate of success had increased chronologically. We then performed 3 subgroup analyses according to instrument type (needles vs knife blades), cortisone use (cortisone vs noncortisone), and sonography guidance (sonography vs non-sonography guidance). Pooled success rates were calculated in the subgroups and compared using chi-square test. RESULTS: A total of 34 studies involving 2,114 percutaneous procedures were included in this systematic review and meta-analysis. The total success rate was 94%. There was a trend toward increasing number of publications in the past 20 years. We found a statistically significant trend showing that overall success rates had increased over time. Chi-square test revealed that percutaneous release with sonography guidance had a significantly higher success rate than non-sonography guidance. There were no significant differences in other subgroup analyses including instrument type and cortisone use. CONCLUSIONS: Percutaneous release is an effective and safe procedure for the treatment of trigger digit. It has become progressively popular in recent years, with a trend toward increased overall success. Sonography might be a helpful tool for maximizing success. The success rates were not affected by instruments and cortisone use. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Comparison of data-fitting models for schistosomiasis: a case study in Xingzi, China.

When modelling prevalence data, epidemiological studies usually employ either Gaussian, binomial or Poisson models. However, reasons are seldom given in the literature why the chosen model was felt to be the most appropriate. In this study, we compared all three models for fitting schistosomiasis risk in Xingzi county, Jiangxi province, People's Republic of China. Parasitological data from conventional surveys were available for 36,208 individuals aged between 6 and 65 years from 42 sampled villages and used in combination with environmental data to map the spatial patterns of schistosomiasis risk. The results show that the Poisson model fitted the data best and this model identified the role of environmental risk factors in explaining the geographical variation of schistosomiasis risk. These factors were further used to develop a predictive map, which has important implications for the control and eventual elimination of schistosomiasis in the People's Republic of China.

[Spatial distribution characteristics of iodine in drinking water in Shandong province between year 2008 and 2010].

OBJECTIVE: To detect the spatial distribution characteristics of iodine in drinking water of residents in Shandong province with spatial autocorrelation analysis. METHODS: The county-based study set Shandong province as a research site. A total of 108 164 water samples from 140 counties were collected. The drinking water iodine data in county-level city between 2008 to 2010 were obtained from Shandong Institute of Prevention and Control for Endemic Disease and was merged with an electronic map to build a spatial database. Global and local Moran's I index were calculated, respectively, and spatial autocorrelation and cluster range of iodine distribution in drinking water in Shandong province were studied by SaTScan software. RESULTS: All counties were further grouped according to the "criteria of delimitation for IDD endemic areas" and "determination and classification of the areas of high water iodine and the endemic areas of iodine excess goiter", and 90 counties were iodine deficiency (< 10 µg/L), 31 were iodine suitable (10 - 150 µg/L), and 19 (> 150 µg/L) were high iodine. For the overall study area, the iodine distribution in drinking water in Shandong province existed spatial autocorrelation (Moran's I = 0.52, Z = 7.4, P < 0.01). For the local scale, the drinking water iodine in 18 counties of Dezhou, Liaocheng and Heze city in western Shandong province was clustered, the local Moran's I were between 0.22 - 1.00 (P < 0.01), which were all high-high clusters, indicating the positive spatial correlation. Spatial analysis using SaTScan software detected two cluster areas including 20 counties, which the centers located in Xiajin and Dingtao county, the cluster radiuses were 57.47 km and 65.58 km respectively. The analysis results were consistent with the results of local spatial autocorrelation. CONCLUSION: There are apparent spatial autocorrelation and strong spatial heterogeneity existed in the iodine distribution in drink water in Shandong province.

[Relationship between snails and recent water level in different marshlands in Xingzi County, Jiangxi Province].

OBJECTIVE: To study the longitudinal change of data on Oncomelania hupensis surveillance in different marshlands and the impact of recent water level in Xingzi County, Jiangxi Province. METHODS: All information including water level of hydrometric station and the data of snails at the marshlands of Xiguanhu, Majiawan and Ximiaoqian was collected to explore the longitudinal change of snails and analyze the relationship between snail distribution and recent water level with Spearman rank correlation analysis. RESULTS: The highest proportion of frames with living snails and living snail densities at Majiawan and Ximiaoqian was 89.66% (442/493) in 2002 and 66.72% (872/1 307) in 2007, 8.33 in 2001 and 7.39 snails per frame in 2006, respectively, and the lowest was 13.26% (126/950) in 2010 and 4.60% (55/1 195) in 2005, 0.42 in 2010 and 0.22 snails per frame in 2002, respectively, and tended to decrease gradually after 2007. At Majiawan, infected snails were found in 2005 and 2009, the density and proportion of infected snails were 0.0033 and 0.0025 snails per frame, 0.09% (3/3 306) and 0.22% (3/1 389). Infected snails were found in Ximiaoqian in 2001, 2003, 2005 and 2009, the highest density and proportion of infected snails were 0.005 0 snails per frame and 0.88% (6/684) in 2005. Infected snails were found in Xiguanhu in 2002 and 2003 with a density and proportion of 0.0029 and 0.0027 snails per frame, 0.10% (1/974) and 0.32% (1/312), respectively. The correlation analysis between proportion of frames with living snails and density at Xiguanhu with the average water level of the first and second month before snail survey showed statistical significance, the correlation coefficient was 0.76, 0.71, 0.82 and 0.78 (P<0.05), respectively. The correlation between proportion of frames with living snails and density at Majiawan showed no statistical significance with the average water level of recent three months before snail survey. The proportion of frames with living snails and density at Xiguanhu were negatively correlated with the average water level of the first and second month before snail survey, the correlation coefficient was -0.67, -0.75, -0.79 and -0.72 (P<0.05), respectively. CONCLUSION: The change trend of snail indicators in different marshlands in the County and impact of water level in recent three months on snail population are both different, and the snail control strategy in marshlands should therefore be adjusted.

[Study on spatial-temporal variation of infected snail in bottomland areas after an integrated control strategy at village level in the marshland and lake regions based on geographic information system].

OBJECTIVE: To evaluate the effect of an integrated control strategy and to quantify the spatial-temporal variation of infected snails in the bottomland areas after the strategy was implemented. METHODS: Based on the geographic database of infected snail distribution at the village level during 2004 - 2010 in Anxiang county, Hunan province, spatial autocorrelation analysis and spatial scan statistics were applied to analyze the spatial-temporal characteristics on the distribution of infected snails. RESULTS: The number of embankments with infected snails in Anxiang county decreased from 23 in 2004 to 10 in 2010, while the rate of frame with infected snail in embankments decreased from 4.32‰ in 2004 to 0.12‰ in 2010. The spatial distribution of infected snails was nonrandom, only in 2004 and 2005 with Moran's I = 0.21 (P < 0.10) and Moran's I = 0.13 (P < 0.10) respectively. Data from the local spatial auto-correlation analysis showed that the number of villages with H-H types of auto-correlation model had been gradually decreasing. The results of SaTScan statistics appeared the same as from the local spatial auto-correlation analysis, showing that the number of areas with increased risk was decreasing. CONCLUSION: The comprehensive measures with emphasis on infectious source control seemed effective for schistosomiasis control program. The current distribution characteristics provided us with evidence that the resource assignment could be more reasonably implemented so as to control schistosomiasis in a more effective way.

[Identification of snail habitats in the Poyang Lake region, based on the application of indices on joint normalized difference vegetation and water].

OBJECTIVE: With Landsat TM remote sensing images, snail habitats in Poyang Lake region were identified, using two indices: the modified normalized difference water index (MNDWI) and the normalized difference vegetation index (NDVI). METHODS: Two Remote sensing images of both wet and drought seasons in Poyang Lake region were obtained. MNDWI and NDVI were extracted from the images respectively, to present the regions of "water in summer and land in winter" and the coverage of vegetation. By overlaying those two regions, the areas of potential snail habitats were drawn. Finally, sensitivities and specificities of the recommended methods were assessed and compared to that of the traditional methods for the sake of extracting the areas of snail habitats. RESULTS: The threshold values of MNDWI for the wet and drought seasons were 0.34 and 0.58, respectively and the threshold value for NDVI of the drought season was 0.02. Sensitivity and specificity of our method were 95% and 100%, respectively, higher than the conventional approach (se. = 75%, sp. = 100%). CONCLUSION: Joint application of MNDWI and NDVI seemed a better method to detect the snail habitats and could be used for the quantitative and automatic surveillance program on snails.

[Application of multi-temporal China-Brazil Earth Recourses Satellite-02 data on surveillance of dynamic changes of water body of rivers and Oncomelania snail habitats in Anxiang County].

OBJECTIVE: To study the dynamic changes of the water body of rivers and Oncomelania snail habitats by using multi-temporal China-Brazil Earth Recourses Satellite-02 images taken in Anxiang County so as to establish the correct procedure for selecting images. METHODS: CBERS-02 images were collected on 20th December 2003, 10th February 2004, 10th April 2004, 19th June 2004, 10th August 2004 and 27th October 2004. Then the water body information from the study areas based on NDWI was extracted and the areas of water body were calculated to determine the images. RESULTS: The dynamic changes of the water body conformed to the rules of "water in summer and land in winter". Because of the rise of water, the water area in July was the biggest and the water area began to decline from August. The water area in April was the smallest. Then the wet season and the dry season should be June and April. CONCLUSION: The multi-temporal CBERS-02 images could be used to surveillance the dynamic changes of the water area and helpful in choosing the right images of the wet season and dry season.

[Study on spatial distribution of advanced schistosomiasis at village level in Anxiang County based on geographic information system].

OBJECTIVE: To explore the spatial distribution and pattern of advanced schistosomiasis in Anxiang County so as to provide the evidence for improving advanced schistosomiasis control. METHODS: Based on the geographic database of advanced schistosomiasis distribution at the village level in Anxiang County, Hunan Province, the spatial autocorrelation analysis and spatial scan statistics were applied to analyze the spatial characteristics of distribution of advanced schistosomiasis. RESULTS: The global Moran's I of prevalence rate of advanced schistosomiasis was 0.06 (P > 0.05) and there was no spatial auto-correlation as a whole. The local spatial auto-correlation analysis showed that there were 9 villages with statistically significant LISA value (P < 0.05), among which existed high-high, low-high and high-low types of auto-correlation model. The results of SaTScan statistics was the same as local spatial auto-correlation analysis and showed the existence of one cluster area. CONCLUSIONS: There are local spatial auto-correlation and spatial aggregation of advanced schistosomiasis in Anxiang County. According to the distribution characteristics, we can assign resource more reasonably and control schistosomiasis more effectively.

[Preliminary study on applying high resolution CBERS images to identify Oncomelania snail habitats in lake and marshland regions].

OBJECTIVE: To explore the preliminary application of high resolution CBERS-02B images in detecting the Oncomelania snail habitats in lake and marshland regions. METHODS: The images with high resolutions were first fused from CBERS-02B HR and CCD images, and then the potential snail habitats in Xingzi County of Jiangxi Province were extracted from high resolution CBERS images and CCD images, respectively. A total of 2 000 validation points were randomly selected for comparing the difference of distribution of these points inside and outside of the extracted two snail habitats with the McNemar chi-square test. RESULTS: The areas of the two snail habitats extracted from high resolution and CCD images were 98.23 km2 and 94.89 km2, respectively. The numbers of validation points in the two snail habitats were 255 and 248, respectively, and no significant difference was found (chi2 =177 9.52, P = 0.23). CONCLUSION: At large-scale studies, the ranges and areas of the two snail habitats extracted from high resolution and CCD images are not significantly different.

[Surveillance of schistosomiasis in Zhuxi Village, Xingzi County, 2005-2010].

OBJECTIVE: To understand the effect of schistosomiasis control in Zhuxi Village, Xingzi County, Jiangxi Province. METHODS: According to the national scheme of schistosomiasis surveillance, we investigated the schistosomiasis epidemic in Zhuxi Village from 2005-2010. The epidemic data of schistosomiasis on the humans, farm cattle, and Oncomelania snails were collected, respectively and analyzed by using the method of Cochran-Armitage test. RESULTS: Human infections and snail infections showed dynamic fluctuations (Z = 3.35, P = 0.000 8) and the density of alive snails tended to decrease gradually. The majority of the infections were peasants and students. The infection rates of farm cattle were 12.31%, 3.23%, 2.94%, 3.33%, 4.44% and 2.15%, respectively from 2005-2010. CONCLUSION: The effect of schistosomiasis control is very fine and schistosomiasis has been well controlled.