Magnesium-Doped Nano-Hydroxyapatite/Polyvinyl Alcohol/Chitosan Composite Hydrogel: Preparation and Characterization.

Background: Polyvinyl alcohol/Chitosan hydrogel is often employed as a carrier because it is non-toxic, biodegradable, and has a three-dimensional network structure. Meanwhile, Magnesium-doped nano-hydroxyapatite(Mg-nHA) demonstrated high characterization to promote the osteogenic differentiation of bone marrow derived mesenchymal stem cell(BMSCs). Therefore, in order to develop a porous hydrogel scaffold for the application of bone tissue engineering, an appropriate-type Mg-nHA hydrogel scaffold was developed and evaluated. Methods: A composite hydrogel containing magnesium-doped nano-hydroxyapatite (Mg-nHA/PVA/CS) was developed using a magnetic stirring-ion exchange method and cyclic freeze-thaw method design, with polyvinyl alcohol and chitosan as the main components. Fourier transform infrared spectra (FTIR), electron energy dispersive spectroscopy (EDS), X-ray photoelectron spectrometer (XPS) and scanning electron microscopy (SEM) were employed to analyze the chemical structure, porosity, and elemental composition of each hydrogels. The equilibrium swelling degree, moisture content, pH change, potential for biomineralization, biocompatibility, the osteogenic potential and magnesium ion release rate of the composite hydrogel were also evaluated. Results: SEM analysis revealed a well-defined 3D spatial structure of micropores in the synthesised hydrogel. FTIR analysis showed that doping nanoparticles had little effect on the hydrogel's structure and both the 5% Mg-nHA/PVA/CS and 10% Mg-nHA/PVA/CS groups promoted amide bond formation. EDS observation indicated that the new material exhibited favourable biomineralization ability, with optimal performance seen in the 5% Mg-nHA/PVA/CS group. The composite hydrogel not only displayed favourable water content, enhanced biocompatibility, and porosity (similar to human cancellous bone), but also maintained an equilibrium swelling degree and released magnesium ions that created an alkaline environment around it. Additionally, it facilitated the proliferation of bone marrow mesenchymal stem cells and their osteogenic differentiation. Conclusion: The Mg-nHA/PVA/CS hydrogel demonstrates significant potential for application in the field of bone repair, making it an excellent composite material for bone tissue engineering.

Charge Dispersion Strategy for High-Performance and Rain-Proof Triboelectric Nanogenerator.

Triboelectric nanogenerator (TENG) is becoming a sustainable and renewable way of energy harvesting and self-powered sensing because of low cost, simple structure, and high efficiency. However, the output current of existing TENGs is still low. It is proposed that the output current of TENGs can be dramatically improved if the triboelectric charges can distribute inside the triboelectric layers. Herein, a novel single-electrode conductive network-based TENG (CN-TENG) is developed by introducing a conductive network of multiwalled carbon nanotubes in dielectric triboelectric layer of thermoplastic polyurethane (TPU). In this CN-TENG, the contact electrification-induced charges distribute on both the surface and interior of the dielectric TPU layer. Thus, the short-circuit current of CN-TENG improves for 100-fold, compared with that of traditional dielectric TENG. In addition, this CN-TENG, even without packing, can work stably in high-humidity environments and even in the rain, which is another main challenge for conventional TENGs due to charge leakage. Further, this CN-TENG is applied for the first time, to successfully distinguish conductive and dielectric materials. This work provides a new and effective strategy to fabricate TENGs with high output current and humidity-resistivity, greatly expanding their practical applications in energy harvesting, movement sensing, human-machine interaction, and so on.

Synthesis Technology of Magnesium-Doped Nanometer Hydroxyapatite: A Review.

Ion substitution techniques for nanoparticles have become an important neighborhood of biomedical engineering and have led to the development of innovative bioactive materials for health systems. Magnesium-doped nanohydroxyapatite (Mg-nHA) has good bone conductivity, biological activity, flexural strength, and fracture toughness due to particle doping technology, making it an ideal candidate material for biomedical applications. In this Review, we have systematically presented the synthesis methods of Mg-nHA and their application in the field of biomedical science and highlighted the pros and cons of each method. Finally, some future prospects for this important neighborhood are proposed. The purpose of this Review is to provide readers with an understanding of this new field of research on bioactive materials with innovative functions and systematically introduce the latest technologies for obtaining uniform, continuous, and morphologically diverse Mg-nHA.

Application of polyvinyl alcohol/chitosan copolymer hydrogels in biomedicine: A review.

Hydrogels is a hydrophilic, cross-linked polymer of three-dimensional network structures. The application of hydrogels prepared from a single polymer in the biomedical field has many drawbacks. The functional blend of polyvinyl alcohol and chitosan allows hydrogels to have better and more desirable properties than those produced from a single polymer, which is a good biomaterial for development and design. In this paper, we have reviewed the progress in the application of polyvinyl alcohol/chitosan composite hydrogels in various medical fields, the different cross-linking agents and cross-linking methods, and the research progress in the optimization of composite hydrogels for their subsequent wide range of biomedical applications.

A novel four-dimensional prediction model of soil heavy metal pollution: Geographical explanations beyond artificial intelligence "black box".

The current artificial intelligence (AI)-based prediction approaches of soil pollutants are inadequate in estimating the geospatial source-sink processes and striking a balance between the interpretability and accuracy, resulting in poor spatial extrapolation and generalization. In this study, we developed and tested a geographically interpretable four-dimensional AI prediction model for soil heavy metal (Cd) contents (4DGISHM) in Shaoguan city of China from 2016 to 2030. The 4DGISHM approach characterized spatio-temporal changes in source-sink processes of soil Cd by estimating spatio-temporal patterns and the effects of drivers and their interactions of soil Cd at local to regional scales using TreeExplainer-based SHAP and parallel ensemble AI algorithms. The results demonstrate that the prediction model achieved MSE and R2 values of 0.012 and 0.938, respectively, at a spatial resolution of 1 km. The predicted areas exceeding the risk control values for soil Cd across Shaoguan from 2022 to 2030 increased by 22.92% at the baseline scenario. By 2030, enterprise and transportation emissions (SHAP values 0.23 and 0.12 mg/kg, respectively) were the major drivers. The influence of driver interactions on soil Cd was marginal. Our approach surpasses the limitations of the AI "black box" by integrating spatio-temporal source-sink explanation and accuracy. This advancement enables geographically precise prediction and control of soil pollutants.

Inflammatory bowel disease can reduce ovarian reserve function in women: A systematic review and meta-analysis.

PURPOSE: We conducted a systematic review and meta-analysis to examine the role of inflammatory bowel disease (IBD) in ovarian reserve functions. METHODS: The PECO strategy was employed. Women of reproductive age (Population) and with IBD (Exposure) were compared with healthy women of reproductive age (Comparison) to evaluate the ovarian reserve function (Outcome). Two reviewers searched three databases as well as relevant gray literature. After following the PRISMA 2020 guidelines, RevMan 5.0 software and Newcastle-Ottawa Scale (NOS) scoring were used to analyze and summarize the data included in the studies. The protocol was registered on PROSPERO (CRD42021267804). RESULTS: The search yielded 367 studies, out of which 13 were selected for full-text evaluation, and finally, seven studies were included in our research. An analysis of ovarian reserve function in IBD women of reproductive age and healthy women revealed that the ovarian reserve function was lower in IBD women of reproductive age than in healthy women (P < .01, I2 = 81%); the ovarian reserve function was significantly lower in women with IBD in remission than in healthy women (P < .01, I2 = 0%), and ovarian reserve function was lower in IBD women of reproductive age taking thalidomide than in healthy women (P < .01, I2 = 18%). CONCLUSION: IBD could reduce ovarian reserve function in women of reproductive age, and patients should plan for conception as soon as possible under permissible conditions.

Hydrogel-Based Flexible Electronics.

Flexible electronics is an emerging field of research involving multiple disciplines, which include but not limited to physics, chemistry, materials science, electronic engineering, and biology. However, the broad applications of flexible electronics are still restricted due to several limitations, including high Young's modulus, poor biocompatibility, and poor responsiveness. Innovative materials aiming for overcoming these drawbacks and boost its practical application is highly desirable. Hydrogel is a class of 3D crosslinked hydrated polymer networks, and its exceptional material properties render it as a promising candidate for the next generation of flexible electronics. Here, the latest methods of synthesizing advanced functional hydrogels and the state-of-art applications of hydrogel-based flexible electronics in various fields are reviewed. More importantly, the correlation between properties of the hydrogel and device performance is discussed here, to have better understanding of the development of flexible electronics by using environmentally responsive hydrogels. Last, perspectives on the current challenges and future directions in the development of hydrogel-based multifunctional flexible electronics are provided.

Multi-response gelation based on the molecular assembly of Sudan I dye derivatives for phase selective gelators and chemosensors.

Sudan I dye-based smart low molecular weight gelators with/without a perfluoroalkyl group have been successfully synthesized and characterized by rheological measurements, scanning electron microscopy (SEM), IR, and NMR spectroscopies. The gelation behaviors in response to temperature, pH changes, metal cations, and UV-vis light irradiation are investigated. Compounds 1 and 2 could selectively sense the Cu2+ cation in the presence of other metal cations. Moreover, compound 2 with a perfluoroalkyl group shows phase selective gelation ability. This work also provides a valuable reference for exploiting photosensitive materials as chemosensors.

Delayed diagnosis and management of necrotizing fasciitis of the left lower leg: A case report.

INTRODUCTION: Necrotizing fasciitis (NF) is a rare, severe soft tissue infection, characterized by rapid and extensive necrosis of the skin, subcutaneous tissue, and superficial and deep fascia. It is frequently misdiagnosed as other infectious diseases, leading to inappropriate treatment and potentially serious consequences. It may be complicated by septic shock and multiple organ failure with a fatal outcome. PATIENT CONCERNS: A 73-year-old woman presented with continuous itching, skin lesions, pain, and swelling of the outer side of her left leg. The patient was diagnosed with septic shock and multiorgan failure caused by left leg NF. DIAGNOSIS: Septic shock and multiorgan failure caused by left leg NF. INTERVENTIONS: Two surgeries were performed on the patient's leg, which effectively treated her septic shock and multiple organ dysfunction. OUTCOMES: The patient was followed up three times after her discharge. She had a good recovery, was generally well with no significant sequelae, and returned to her regular life. CONCLUSION: NF is an acute severe illness with high mortality. It is easily misdiagnosed, leading to delayed or erroneous treatment and serious (or potentially fatal) outcomes. Rapid and accurate diagnosis of NF is essential for patient recovery. In difficult cases, multidisciplinary consultations may be helpful. The management of NF includes early and thorough surgical debridement, antibiotics, and symptomatic treatment.

Scedosporium apiospermum infection of the lumbar vertebrae: A case report.

BACKGROUND: Scedosporium apiospermum (S. apiospermum) is a clinically rare and aggressive fungus mainly found in contaminated water, wetlands, decaying plants, stagnant water, and potted plants in hospitals. The lung, bone, joint, eye, brain, skin, and other sites are easily infected, and there is a marked risk of misdiagnosis. There have been few case reports of infection by S. apiospermum of the lumbar vertebrae; most reports have focused on infection of the lung. CASE SUMMARY: An otherwise healthy 60-year-old man presented with a 4-mo history of lumbosacral pain, stooping, and limited walking. The symptoms were significantly aggravated 10 d prior to hospitalization, and radiating pain in the back of his left lower leg developed, which was so severe that he could not walk. Movement of the lumbar spine was significantly limited, anterior flexion was about 30°; backward extension, right and left lateral curvature, and rotational mobility were about 10°; tenderness of the spinous processes of the lumbar 3-5 vertebrae was evident, and the muscle strength of both lower limbs was grade IV. Imaging suggested bony destruction of the lumbar 3, 4, and 5 vertebrae and sacral 1 vertebra; in addition, the corresponding intervertebral spaces were narrowed and the lumbar 5 vertebra was posteriorly displaced and unstable. Lumbar vertebral infection was also noted, and the possibility of lumbar tuberculosis was considered. We first performed surgical intervention on the lesioned lumbar vertebrae, cleared the infected lesion, and performed stable fixation of the lesioned vertebral body using a lumbar internal fixation device, which restored the stability of the lumbar vertebrae. Cytological and pathological examination of the lesioned tissue removed during surgery confirmed S. apiospermum infection of the lumbar vertebrae; on this basis, the patient was administered voriconazole. At the 6-mo follow-up, efficacy was significant, no drug-related side effects were observed, and imaging examination showed no evidence of recurrence. CONCLUSION: S. apiospermum infection can occur in immunocompetent individuals with no history of near drowning. Voriconazole is effective for the treatment of S. apiospermum infection of the lumbar vertebrae for which it is suitable as the first-line therapy.

Lumbar disc sequestration mimicking a tumor: Report of four cases and a literature review.

BACKGROUND: Disc herniation refers to the displacement of disc material beyond its anatomical space. Disc sequestration is defined as migration of the herniated disc fragment into the epidural space, completely separating it from the parent disc. The fragment can move in upward, inferior, and lateral directions, which often causes low back pain and discomfort, abnormal sensation, and movement of lower limbs. The free disc fragments detached from the parent disc often mimic spinal tumors. Tumor like lumbar disc herniation can cause clinical symptoms similar to spinal tumors, such as lumbar soreness, pain, numbness and weakness of lower limbs, radiation pain of lower limbs, etc. It is usually necessary to diagnose the disease according to the doctor's clinical experience, and make preliminary diagnosis and differential diagnosis with the help of magnetic resonance imaging (MRI) and contrast-enhanced MRI. However, pathological examination is the gold standard that distinguishes tumoral from non-tumoral status. We report four cases of disc herniation mimicking a tumor, and all the pathological results were intervertebral disc tissue. CASE SUMMARY: The first case was a 71-year-old man with low back pain accompanied by left lower extremity radiating pain for 1 year, with exacerbation over the last 2 wk. After admission, MRI revealed a circular T2-hypointense lesion in the spinal canal of the L4 vertebral segment, with enhancement on contrast-enhanced MRI suggesting neurilemmoma. The second case was a 74-year-old man with pain in both knees associated with movement limitation for 3 years, with exacerbation over the last 3 mo. MRI revealed an oval T2-hyperintense lesion in the spinal canal at the L4-5 level, with obvious peripheral enhancement on contrast-enhanced MRI. Thus, neurilemmoma was suspected. The third case was a 53-year-old man who presented with numbness and weakness of the lumbar spine and right lower extremity for 2 wk. MRI revealed a round T2-hyperintense lesion in the spinal canal at the L4-5 level, with obvious rim enhancement on contrast-enhanced MRI. Thus, a spinal tumor was suspected. The fourth case was a 75-year-old man with right lower extremity pain for 2 wk, with exacerbation over the last week. MRI revealed a round T1-isointense lesion in the spinal canal of the L3 vertebral segment and a T2-hyperintense signal from the lesion. There was no obvious enhancement on contrast-enhanced MRI, so a spinal tumor was suspected. All four patients underwent surgery and recovered to ASIA grade E on postoperative days 5, 8, 8, and 6, respectively. All patients had an uneventful postoperative course and fully recovered within 3 mo. CONCLUSION: Disc herniation mimicking a tumor is a relatively rare clinical entity and can be easily misdiagnosed as a spinal tumor. Examinations and tests should be improved preoperatively. Patients should undergo comprehensive preoperative evaluations, and the lesions should be removed surgically and confirmed by pathological diagnosis.

In vitro drug release and antibacterial activity evaluation of silk fibroin coated vancomycin hydrochloride loaded poly (lactic-co-glycolic acid) (PLGA) sustained release microspheres.

Currently, the treatment of osteomyelitis poses a great challenge to clinical orthopedics. The use of biodegradable materials combined with antibiotics provides a completely new option for the treatment of osteomyelitis. In this study, vancomycin hydrochloride (VANCO) loaded poly (lactic-co-glycolic acid) (PLGA) microspheres were prepared by a double emulsion solvent evaporation method, and the in vitro drug release behaviors of the drug loaded microspheres were explored after coating with different concentrations of silk fibroin (SF). Drug loading, encapsulation efficiency, Scanning electron microscopy, particle size analysis, Fourier transform infrared spectroscopy, hydrophilicity, in vitro drug release, and in vitro antibacterial activity were evaluated. The results showed that the drug loading of vancomycin loaded PLGA microspheres was (24.11 ±1.72)%, and the encapsulation efficiency was (48.21 ±3.44)%. The in vitro drug release indicated that the drug loaded microspheres showed an obvious initial burst release, and the drug loaded microspheres coated with SF could alleviate the initial burst release in varying degrees. It also can reduce the amount of cumulative drug release, and the effect of microspheres coated with 0.1% concentration of SF is the best. The time of in vitro drug release in different groups of drug loaded microspheres can be up to 28 days. The microspheres coated with (0.1%SF) or without (0%SF) SF showed a cumulative release of (82.50±3.51)% and (67.70±3.81)%,respectively. Therefore, the surface coating with SF of vancomycin loaded microspheres can alleviate the initial burst release, reduce the cumulative drug release, potentially prolong the drug action time, and improve the anti-infection effect.

[Progress in the application of silk fibroin in tissue engineered drug delivery system].

OBJECTIVE: The properties and characteristics of different types of silk fibroin (SF) drug-loaded sustained-release carriers and their effects on the drug release behavior were reviewed, and the existing problems and development prospects of SF drug-loaded sustained-release carriers in tissue engineering drug delivery system were discussed. METHODS: The literatures about drug-loaded SF sustained-release carriers in recent years were extensively consulted, and the types of sustained-release carriers, characteristics of drug release, range of applications, advantages and disadvantages, and solutions were summarized and analyzed. RESULTS: At present, the SF drug-loaded sustained-release carriers are mainly divided into SF microparticles, SF scaffolds, SF membranes, SF hydrogels, SF nanofibers, SF sponges, and so on. These types of SF drug-loaded sustained-release carriers have their own advantages and problems, of which the most prominent problem is the burst release of drugs at the initial stage. While, the initial burst release of drugs can be effectively solved by improving the preparation process and adjusting the material ratio. Different types of drug-loaded sustained-release carriers can be prepared by combining different materials to achieve different application scopes and drug release behaviors under different conditions. CONCLUSION: SF is a good drug-loaded carrier for tissue engineering, the burst release of drugs at the initial stage can be solved by improving the preparation process and changing the material structure; through the combination of the advantages of various types of SF drug-loaded sustained-release carriers, it is expected to prepare SF drug-loaded sustained-release carriers that meet different clinical needs.

Possible Luttinger liquid behavior of edge transport in monolayer transition metal dichalcogenide crystals.

In atomically-thin two-dimensional (2D) semiconductors, the nonuniformity in current flow due to its edge states may alter and even dictate the charge transport properties of the entire device. However, the influence of the edge states on electrical transport in 2D materials has not been sufficiently explored to date. Here, we systematically quantify the edge state contribution to electrical transport in monolayer MoS2/WSe2 field-effect transistors, revealing that the charge transport at low temperature is dominated by the edge conduction with the nonlinear behavior. The metallic edge states are revealed by scanning probe microscopy, scanning Kelvin probe force microscopy and first-principle calculations. Further analyses demonstrate that the edge-state dominated nonlinear transport shows a universal power-law scaling relationship with both temperature and bias voltage, which can be well explained by the 1D Luttinger liquid theory. These findings demonstrate the Luttinger liquid behavior in 2D materials and offer important insights into designing 2D electronics.

Genetic Association Between CDKN1B rs2066827 Polymorphism and Susceptibility to Cancer.

Much attention has been directed to the association between cancer risk and rs2066827 polymorphism of the CDKN1B gene. However, the results are indefinitive and inconclusive. This study was devised to evaluate the hypothesis that rs2066827 polymorphism is associated with the risk of cancer.Computer-based databases (EMBASE, PubMed, and CNKI) were used to seek all case-control studies evaluating rs2066827 polymorphism and susceptibility to cancer. The genetic risk was assessed by calculating pooled odds ratio (OR) with its corresponding 95% confidence interval (CI). Fixed-effects pooled ORs were calculated by the Mantel-Haenszel method (Ph > 0.05), and random-effects pooled ORs were estimated by the DerSimonian-Laird method (Ph < 0.05).Data on rs2066827 polymorphism and cancer risk were available for 9038 cancer cases and 11,596 controls participating in 17 studies. Carriage of a TG genotype was associated with a minor but significant decrease in the risk of cancer (pooled OR 0.92, 95% CI: 0.86-0.99; model, TG vs. TT). We observed a moderately decreased risk of ovarian cancer based on 1829 cases and 2868 controls (pooled OR 0.85, 95% CI: 0.74-0.97; model, TG vs. TT). A slightly deceased risk of cancer was also indicated in Caucasians consisting of 6707 cases and 8279 controls (pooled OR 0.91, 95% CI: 0.85-0.98; model, TG vs. TT).These data suggest that carriage of a TG genotype at rs2066827 polymorphism may be associated with decreased susceptibility to cancer, ovarian cancer in particular.

[Monitoring of sentinel mice and risk assessment of schistosomiasis transmission in key regions of Yunnan Province in 2014].

OBJECTIVE: To establish and perfect the surveillance and forecast system of schistosomiasis, and timely discover the suspicious high risk environments for preventing the human and livestock from schistosomiasis. METHODS: Eight villages of three counties were selected as survey points. Then, the surveillance and forecast of sentinel mice were carried out in the key water regions. The recovered sentinel mice were dissected in laboratory. The sentinel mouse serum antibodies against schistosome were detected by ELISA, the suspicious water contacts of residents and livestock were investigated and the results were analyzed, and the epidemic risk was assessed. RESULTS: Totally 300 sentinel mice were placed, the recovery rate was 94.67%, and the mortality rate was 8.80%. There were no mice with positive serum antibodies against schistosome, and the results of the dissection of all the sentinel mice were negative. The humans who contacted with the suspicious water were mainly villagers, students, children and fishermen by washing hands and feet, washing vegetables, harvesting, fishing and swimming. The Oncomelania hupensis snail areas, human infection rates, and cattle infection rates were obviously declined in recent 3 years. However, the epidemic risks still existed. CONCLUSION: Although schistosomiasis transmission was effectively controlled in the three counties, the comprehensive control measures still should be strengthened.

The role of O(6)-methylguanine-DNA methyltransferase polymorphisms in colorectal cancer susceptibility: a meta analysis.

OBJECTIVE: O(6)-methylguanine DNA methyl-transferase gene (MGMT) is a central DNA repair mechanism with a significant role in removing DNA damage caused by alkylating agents and inhibiting human oncogenesis. Two single polymorphisms in the MGMT gene, Leu84Phe and Ile143Val, have been reported to affect DNA repair capability and enzymic activity, thereby leading to formation of different cancers. In this work, we quantitatively assess the associations between MGMT polymorphisms and risk of colorectal cancer (CRC), as previous studies has implicated inconsistencies in their results. METHODS: Analysis was performed on all usable data collected from the eligible studies that were searched in multiple bibliographical databases (PubMed, SCOPUS, and Embase). RESULTS: We obtained studies on Leu84Phe and Ile143Val, providing 6,154 and 7,371 samples, respectively. In the analysis on Leu84Phe, the SNP presented no global association with CRC at both the genotypic and the allelic level, but a trend towards an increased or decreased risk was shown in the models examined. Stratification by ethnicity revealed a significant increase in risk of CRC related to the Phe/Phe genotype in Caucasian samples (homozygote genetic model: OR=1.70, 95% CI=1.06-2.72; recessive genetic model: OR=1.80, 95% CI=1.12-2.87). CONCLUSIONS: Based on the statistical data, our meta-analysis indicates that Leu84Phe polymorphism in the MGMT gene may predispose Caucasians to CRC.

Eco-social determinants of Schistosoma japonicum infection supported by multi-level modelling in Eryuan county, People's Republic of China.

Schistosomiasis remains of considerable public health concern in many tropical and subtropical regions of the world, including the People's Republic of China (P.R. China). The effectiveness of schistosomiasis control interventions are, among other factors, governed by the social-ecological context. However, eco-social determinants of schistosomiasis are poorly understood, particularly at the household or village levels. In the current study, residents in 26 villages of Eryuan county, Yunnan province, P.R. China, were screened for Schistosoma japonicum infection with a serological assay that was followed by stool examination for sero-positive individuals. Bayesian multilevel models with spatial random effects were employed to profile the S. japonicum infection risk based on known transmission sites of S. japonicum that are scattered across individual land parcels in this part of the country. The key risk factors identified with this approach were the absence of a sanitary stall house for livestock and presence of living and infected intermediate host snails in close proximity. We conclude that a spatially explicit Bayesian multilevel approach can deepen our understanding of eco-social determinants that govern schistosomiasis transmission at a small geographical scale.

[Study on spatio-temporal pattern of mountainous Oncomelania hupensis snails at village scale in Eryuan County, Yunnan Province].

OBJECTIVE: To develop a spatio-temporal model of mountainous Oncomelania hupensis snails based on the Bayesian model, and to analyze and identify the spatio-temporal pattern at a village scale. METHODS: The data including the intensity and spatial distribution of live and infected snails from 2000 to 2006 and the village boundary were collected. The independent and interactive spatio-temporal models were established, and then the best fitness model was selected to analyze the spatio-temporal pattern of live and infected snails. RESULTS: The interactive model of live snails and the independent model of infected snails were relative fitness models, and the models showed 95% CI (confidence interval) of the spatial and temporal coefficient included zero, and indicated that the spatial and temporal correlation of live and infected snails was not significant at a village scale. CONCLUSION: There is no significant spatial and temporal correlation of live and infected mountainous snails at a village scale, and the furthermore study should be carried out at a small scale.

[Effect of water- saving irrigation engineering on schistosomiasis control in Eryuan County of Yunnan Province].

OBJECTIVE: To evaluate the effect of a water-saving irrigation project on schistosomiasis control. METHODS: The Oncomelania snail situation before and after the water-saving irrigation project was investigated, and the data of snails and schistosomiasis of people in the area of the water-saving irrigation engineering were collected and analyzed statistically. RESULTS: The incidence of frames with snails declined from 10.70% to 2.27% after actualized water-saving irrigation project, and the snail density declined from 0.42 snails/0.1 m(2) to 0.10 snails/0.1 m(2). The snails were eliminated in 57% of the ditches. The snail area and schistosome infection rate of residents declined obviously. CONCLUSION: The water-saving irrigation project is effective in schistosomiasis control and has good social and economic benefits.