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ObjectiveIn recent years, there has been a significant increase in the severity of leaf diseases in maize, with a noticeable trend of mixed occurrence. This poses a serious threat to the yield and quality of maize. However, there is a lack of studies that combine the identification of different types of leaf diseases and their severity classification, which cannot meet the needs of disease prevention and control under the mixed occurrence of different diseases and different severities in actual maize fields.MethodsA method was proposed for identifying the types of typical leaf diseases in maize and classifying their severity using hyperspectral technology. Hyperspectral data of three leaf diseases of maize: northern corn leaf blight (NCLB), southern corn leaf blight (SCLB) and southern corn rust (SCR), were obtained through greenhouse pathogen inoculation and natural inoculation. The spectral data were preprocessed by spectral standardization, SG filtering, sensitive band extraction and vegetation index calculation, to explore the spectral characteristics of the three leaf diseases of maize. Then, the inverse frequency weighting method was utilized to balance the number of samples to reduce the overfitting phenomenon caused by sample imbalance. Relief-F and variable selection using random forests (VSURF) method were employed to optimize the sensitive spectral features, including band features and vegetation index features, to construct models for disease type identification based on the full stages of disease development (including all disease severities) and for individual disease severities using several representative machine learning approaches, demonstrating the effectiveness of the research method. Furthermore, the study individual occurrence severity classification models were also constructed for each single maize leaf disease, including the NCLB, SCLB and SCR severity classification models, respectively, aiming to achieve full-process recognition and disease severity classification for different leaf diseases. Overall accuracy (OA) and Macro F1 were used to evaluate the model accuracy in this study.Results and DiscussionThe research results showed significant spectrum changes of three kinds of maize leaf diseases primarily focusing on the visible (550-680 nm), red edge (740-760 nm), near-infrared (760-1 000 nm) and shortwave infrared (1 300-1 800 nm) bands. Disease-specific spectral features, optimized based on disease spectral response rules, effectively identified disease species and classify their severity. Moreover, vegetation index features were more effective in identifying disease-specific information than sensitive band features. This was primarily due to the noise and information redundancy present in the selected hyperspectral sensitive bands, whereas vegetation index could reduce the influence of background and atmospheric noise to a certain extent by integrating relevant spectral signals through band calculation, so as to achieve higher precision in the model. Among several machine learning algorithms, the support vector machine (SVM) method exhibited better robustness than random forest (RF) and decision tree (DT). In the full stage of disease development, the optimal overall accuracy (OA) of the disease classification model constructed by SVM based on vegetation index reached 77.51%, with a Macro F1 of 0.77, representing a 28.75% increase in OA and 0.30 higher of Macro F1 compared to the model based on sensitive bands. Additionally, the accuracy of the disease classification model with a single severity of the disease increased with the severity of the disease. The accuracy of disease classification during the early stage of disease development (OA=70.31%) closely approached that of the full disease development stage (OA=77.51%). Subsequently, in the moderate disease severity stage, the optimal accuracy of disease classification (OA=80.00%) surpassed the optimal accuracy of disease classification in the full disease development stage. Furthermore, the optimal accuracy of disease classification under severe severity reached 95.06%, with a Macro F1 of 0.94. This heightened accuracy during the severity stage can be attributed to significant changes in pigment content, water content and cell structure of the diseased leaves, intensifying the spectral response of each disease and enhancing the differentiation between different diseases. In disease severity classification model, the optimal accuracy of the three models for maize leaf disease severity all exceeded 70%. Among the three kinds of disease severity classification results, the NCLB severity classification model exhibited the best performance. The NCLB severity classification model, utilizing SVM based on the optimal vegetation index features, achieved an OA of 86.25%, with a Macro F1 of 0.85. In comparison, the accuracy of the SCLB severity classification model (OA=70.35%, Macro F1=0.70) and SCR severity classification model (OA=71.39%, Macro F1=0.69) were lower than that of NCLB.ConclusionsThe aforementioned results demonstrate the potential to effectively identify and classify the types and severity of common leaf diseases in maize using hyperspectral data. This lays the groundwork for research and provides a theoretical basis for large-scale crop disease monitoring, contributing to precision prevention and control as well as promoting green agriculture.

Metabolic syndromes (Mets) is a high-risk factor for a series of cardiovascular diseases. Changes in iodine nutritional status can directly mediate the occurrence of insulin resistance, affect glucose and lipid metabolism and the regulation of blood pressure and also,may contribute to the pathogenesis of Mets by regulating thyroid function. Exploring the role of iodine in the occurrence and development of Mets can provide new ideas for the prevention and treatment of Mets.

Diabetic kidney disease has obvious family aggregation and ethnic differences, some single nucleotide polymorphisms (SNPs) related to the susceptibility of diabetic kidney disease have been identified, especially engulfment and cell motility 1 (ELMO1) and solute carrier family 12 member 3(SLC12A3), which are related to the development of diabetic kidney disease in Chinese population. Meanwhile, inflammation plays a key role in the occurrence and development of diabetic kidney disease, including T cell and type-2 innate lymphoid cell(ILC2) promote chronic inflammatory response and fibrosis of kidney by secreting inflammatory factors.

In view of problems that present discriminated methods of water burst source ca't realize prediction of water burst and has long processing time and high complexity, the paper designed a water quality detection system which adopts laser induce fluorescence technology and uses FPGA as core processor. Through on-line detection of fluorescence spectrum, the system can real-timely monitor changes of chemical components of underground water and rapidly monitor movement precursor of the water burst source, so as to achieve forewarning of water burst. The test results show that the system has high detection precision and fast response speed.

The delineation of the urban growth boundary (UGB) in Dalian has a positive effect on coordinating the contradiction between urban expansion and ecological environment protection. Taking Dalian as an example, based on the evaluation of the 5 ecosystem services (ESs): water yield, soil conservation, carbon sequestration, habitat quality, and ecological leisure, the priority protection areas are selected based on the OWA (ordered weighted averaging) operator, making it an ecological red line protection zone, and the UGB of this city is obtained through the simulation of urban expansion by GeoSOS-FLUS model. The results are as follows. 1) From 2017 to 2019, the annual average values of 5 ESs are moderately low in Dalian, with high values in northeast and low values in southwest. 2) The area of the ecological red line protection zone accounts for 17.49% of the total area of the study area, which is continuously distributed in the northeast and scattered in the southwest of Dalian. 3) While the flexible UGB area accounts for 15.71% of the city area in 2030 and is concentrated in the southwest of the city, the delineation results are consistent with the future development pattern of Dalian, showing a "cluster" development pattern. From the perspective of the tradeoffs of ecosystem services, the rational delineation of urban growth boundary is more conducive to the protection of ecological space, and provides reference for the reasonable management of UGB. [ABSTRACT FROM AUTHOR]

Ensuring food security is a fundamental issue for global sustainable development. Sustainable food production is the basis for food security and an effective approach to address global challenges such as climate change, land degradation, and ecological degradation. At present, there is a data gap in the monitoring and assessment of the sustainability of food production, and the supporting role of the Big Earth Data is increasingly prominent. This paper summarizes the current practice of Big Earth Data in support of sustainable food production, including the role of Earth observation technology in the monitoring of various elements of food production system, and the application of multi-source data fusion in the monitoring of comprehensive food production system and the assessment of the sustainability of food production. Based on the review, according the framework of four levers for achieving Sustainable Development Goals (SDGs), we promote two suggestions for future development on Big Earth Data in support of sustainable food production: (1) integrating Big Earth Data with multidisciplinary models to promote knowledge discovery thus supporting governance, and (2) integrating Big Earth Data with technological innovation to build intelligent agriculture for on-farm sustainable food production system. [ABSTRACT FROM AUTHOR]

In order to obtain visually pleasing image, this paper proposed an image interpolation method. It constructed training sample set based on the original image using the known pixel gray values and the correlation within the neighborhood pixels. Next, it used rough sets to reduce the training sample set, and trained the support vector machine with the reduced training sample set. Then, it estimated the pixel gray values in even row even column using the trained support vector machine. Finally, it estimated the pixel gray values in odd row even column and in even row odd column using the trained support vector machine. Simulation results show that the proposed method increases the efficiency of interpolation methods, improves the magnified image edge blurring, and obtains better objective indicators. [ABSTRACT FROM AUTHOR]

Normalized difference vegetation index (NDVI) is an important indicator reflecting vegetation cover and growth status. It is of significance for regional ecological conservation and natural resource management to investigate its spatial and temporal variation trends and response to ecological factors. We divided Liaoning Province into three ecological geographical regions, including northwest agro-pastoral zone, central agricultural zone, and eastern agroforestry zone. Based on remote sensing, vegetation, climate, topography and human activities, we used trend analysis and geographic probe model to examine the spatial and temporal trends of NDVI in Liaoning Province, and analyzed the intensity and interaction mechanism of each driver on the spatial distribution pattern of NDVI. The results showed that the annual average NDVI in Liaoning Province from 2001 to 2020 was 0-0.92, showing a distribution pattern of high in the east and low in the west, high in the inland and low in the coastal land. The overall trend of vegetation cover was increasing, and the NDVI increasing areas were mainly concentrated in the northwest agro-pastoral zone and the eastern agroforestry zone, the NDVI reduction areas were mainly concentrated at the border between the central agricultural zone and the eastern agroforestry zone, as well as in the coastal area of the eastern agroforestry zone. The annual average NDVI change varied among the three ecological-geographic zones. The NDVI of the northwest agro-pastoral zone from 2001 to 2020 were generally low, but showed a fluctuating trend of slow increase. The NDVI of the eastern agroforestry zone was high overall, and the interannual variation of NDVI was generally stable. The distribution of high and low NDVI in the central agricultural zone was staggered, and the interannual variation of NDVI showed a decreasing trend. Natural factors were the key drivers of NDVI changes in the three ecogeographic zones, with cumulative temperature and precipitation having the greatest influence. The interactions between the factors were all mutually and nonlinearly enhanced.

The chemical constituents from the fruits of Morinda citrifolia were systematically explored by chromatographic fractionation methods including silica gel, octadecylsilyl(ODS) gel, Sephadex LH-20 gel, and preparative high performance liquid chromatography(pre-HPLC). The chemical structures of all isolated compounds were identified on the basis of their physicochemical properties, spectroscopic analyses, as well as the comparisons of their physicochemical and spectroscopic data with the reported data in literature. As a result, 22 isolated compounds from the 90% ethanol extract of the fruits of M. citrifolia were identified, which were moricitritone(1), 2'-deoxythymidine(2), cyclo-(L-Pro-L-Tyr)(3), methyl-5-hydroxy-2-pyridinecarboxylate(4), methyl pyroglutamate(5), bisbenzopyran(6), epipinoresinol(7), 3, 3'-bisdemethyl pinoresinol(8), 3, 3'-bisdemethyltanegool(9), trimesic acid(10), crypticin B(11), kojic acid(12), vanillic acid(13), protocatechoic acid(14), 5-hydroxymethyl furfural(15), blumenol A(16), 1-O-(9Z, 12Z-octadecadienoyl) glycerol(17), mucic acid dimethylester(18), methyl 2-O-β-D-glucopyranosylbenzoate(19), 2-phenylethyl-O-β-D-glucoside(20), scopoletin(21), and quercetin(22). Among them, compound 1 was a new pyrone derivative, compounds 2, 4-7, 10-12, and 17 were isolated from the plants belonging to Morinda genus for the first time, and compound 18 was obtained from M. citrifolia for the first time. Moreover, on the basis of testing the activities of all isolated compounds on inhibiting the proliferation of synovial fibroblasts in vitro by MTS assay, the anti-rheumatoid arthritis activities of all isolated compounds were initially evaluated. The results showed that compounds 1-6, 9, 19, and 20 exhibited remarkable anti-rheumatoid arthritis activities, which displayed the inhibitory effects on the proliferation of MH7A synovial fibroblast cells with the IC_(50) values in the range of(3.69±0.08) to(168.96±0.98) μmol·L~(-1).

The chemical constituents from the branches and leaves of Artocarpus incisus were isolated and purified via silica gel, ODS, and Sephadex LH-20 column chromatography as well as preparative HPLC. The chemical structures of all isolated compounds were identified in the light of their physicochemical properties, spectroscopic analyses, and comparisons of their physicochemical and spectroscopic data with the reported data in literature. As a result, 20 compounds were isolated and characterized from the 90% ethanol extract of the branches and leaves of A. incisus, which were identified as tephrosin(1), 6-hydroxy-6 a, 12 a-dehydrodeguelin(2), sarcolobin(3), lupiwighteone(4), 12-deoxo-12α-methoxyelliptone(5), 6 aα,12 aα-12 a-hydroxyelliptone(6), homopterocarpin(7), 3-hydroxy-8,9-dimethoxypterocarpan(8), pterocarpin(9), maackiain(10), medicarpin(11), calycosin(12), genistein(13), formononetin(14), 5-hydroxy-4',7-dimethoxy isoflavone(15), liquiritigenin(16), 4(15)-eudesmene-1β,7α-diol(17), ent-4(15)-eudesmene-1β,6α-diol(18), 1α-hydroxyisodauc-4-en-15-al(19), and guaianediol(20). Except compounds 13 and 16, all other compounds were isolated from the Artocarpus plants for the first time. Additionally, using MTS assay, compounds 1-20 were eva-luated for their anti-rheumatoid arthritis activities by measuring their anti-proliferative effects on synoviocytes in vitro. As a consequence, compounds 1-16 showed notable anti-rheumatoid arthritis activities, which displayed inhibitory effects on the proliferation of MH7 A synovial fibroblast cells, with the IC_(50) values in range of(9.86±0.09)-(218.07±1.96) μmol·L~(-1).

Objective: To investigate the effect of refined moxibustion on expression of gastric mucosal epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF), and changes of metabolite profiles in gastric ulcer (GU) rats, so as to analyze its mechanism underlying improvement of GU., Methods: Male SD rats were randomized into control, model, acupoint moxibustion groups ( n =6 per group). The GU model was induced by cold-restraint stress. The ignited refined moxa was applied to bilateral "Liangmen" (ST21) and "Zusanli" (ST36) for 3 cones/acupoint, once daily for 7 days. Then, we employed 1H NMR-based metabolomics approach to analyze the metabolic profiles of serum and stomach tissue samples. The conventional histopathological changes of the gastric mucosa were observed by H.E. stain and the expressions of EGFR and VEGF in the gastric mucosa were detected by immunohistochemistry., Results: Compared to the control group, the expression levels of EGFR and VEGF were significantly increased in the model group ( P <0.01, P <0.05), and further notably up-regulated in the acupoint moxibustion group ( P <0.001, P <0.01). Results of H.E. staining showed damage of the folds of gastric mucosa, disordered arrangement of the glands, infiltration of inflammatory cells and unclear structure of gastric mucosa in the model group, which was relatively milder in the acupoint moxibustion group. 1H-NMR technical analysis showed that in comparison with the control group, 11 and 11 metabolites in the stomach extract and plasma were increased, 10 in the gastric tissue and 3 in the plasma were decreased in the GU model group; while in comparison with the model group, 17 differently expressed metabolites in the gastric extract and 10 metabolites in the plasma restored to their levels of control group after the acupoint moxibustion intervention. These metabolites participate in 12 metabolic pathways including glycine, serine and threonine metabolism, glutathione metabolism, glycine metabolism, alanine, aspartic acid and glutamic acid metabolism, purine metabolism, glyoxylic acid and digarboxylic acid metabolism, biosynthesis of aminoacyl-tRNA, amino sugar and nucleotide sugar metabolism, cysteine and methionine metabolism, citrate cycle, pyruvate metabolism, and the mutual conversion of pentose and glucuronate，suggesting their involvement in moxibustion-induced improvement of GU., Conclusion: Refined moxibustion at ST21 and ST36 can up-regulate the expression of EGFR and VEGF in the gastric mucosa and lessen gastric mucosal injury, which may be related to its effects in reducing GU-induced metabolic disorders, including sugar, purine, amino acid, and phospholipid metabolism and antioxidant defense system.

Alcohol is considered to be one of the main causes for gastric injury, and alcoholic gastric injury has been becoming one of the global health problems, which seriously affects the quality of human life. Many studies suggest that the active components extracted from Chinese herbal medicine can effectively reduce the degree of alcohol-induced gastric injury. The active components and its mechanism of anti-alcoholic gastric injury of Chinese herbal medicine reported in recent five years were preliminarily summarized according to the classification of terpenoids, flavonoids, polyphenols, polysaccharides, volatile oils, phenylpropanoids and alkaloids in this paper. The terpenoids could improve oxidative stress and inflammatory response by regulating relevant signaling pathways. The flavonoids are mainly related to antioxidant and anti-inflammatory properties. The polyphenols mainly regulate the level of relevant factors involved in inflammatory pathway, oxidative stress and apoptosis pathway. The polysaccharides could enhance the ability of gastric mucosal defense factor by inhibiting oxidative stress injury and inflammatory response. Phenylpropanoids could enhance the gastric mucosal defense factor. The volatile oils mainly inhibit H~+/K~+-ATPase activity or inflammatory reaction. Alkaloids are closely related to the inhibition of inflammatory response and the improvement of antioxidant system. This paper aims to provide reference for further research and development of Chinese herbal medicine against alcoholic gastric injury.

Depression is a kind of mental disease with main symptoms of low mood and lack of pleasure, which seriously endangers human health. An appropriate depressive animal model is of great significance for the study of depression and new antidepressant drugs, while the suitable selection and matching of experimental animals, modeling methods and evaluation indexes are critical to eva-luate the scientificity and effectiveness of the depressive animal model. The study advance of depressive animal models in the aspects of experimental animal selection, modeling principle and method, characteristics, evaluation indexes and their application in traditional Chinese medicine are summarized through the systematic review of relevant literatures in PubMed, CNKI and other databases. The depressive animal modeling methods utilized in recent studies include stress, glucocorticoid induction, reserpine induction, lipopolysaccharide induction, surgical modeling, gene knockout, joint application modeling methods. Stress method is better to simulate the depressive symptoms of clinical patients, whereas there are some deficiencies, such as long modeling time and large cost. The depressive animal models induced by glucocorticoid, reserpine and lipopolysaccharide have the advantages of short modeling time and good controllability, but with a poor reliability. The pathogenesis of surgical modeling is highly matched with that of clinical depressive patients, whereas it has the defect of long postoperative recovery period. Gene knockout models can be used to study the precise role of specific genes in depression. However, its applicability may be restricted in studies on depression. The joint application modeling method can improve its reliability and accuracy, and attracts more and more attention. This paper provides a reference for the selection of animal models in future studies of pathological mechanism of depression, and screening and evaluation of antidepressant drugs.

Objective: To conclude of the technical notes of percutaneous transforaminal endoscope-assisted lumbar interbody fusion (PT-Endo-LIF), and to investigate its safety and efficacy for treatment of degenerative lumbar disease., Methods: Twenty-four patients were treated by PT-Endo-LIF combined with posterior percutaneous pedicle screws fixation from October 2017 to April 2018. There were 16 males and 8 females, ranging in age from 39 to 72 years old, with a mean of (59.6±9.5) years old. There were 15 cases diagnosed with lumbar intervertebral disc herniation combined with degenerative disc, the other 9 cases were diagnosed as low level lumbar spondylolistheses w/o segmental instability. Single segmental fusion was performed for 22 cases(one for L₂,₃, 3 for L₃,₄ and 18 for L₄,₅) and 2 segmental fusion was performed for the other 2 cases (both for L₃,₄ and L₄,₅). PT-Endo-LIF was performed under local anesthesia with conscious sedation, followed by decompression through endoscopic technics. After that, end-plate preparation and autogenous bone and expandable cage implantation were performed. Finally, percutaneous screws and rod instrumentation were used. The visual analogue scale (VAS) and Oswestry Disability Index (ODI) were used to evaluate the clinical efficacy. The operation time, intraoperative bleeding volume, intraoperative and postoperative complications were recorded. All patients underwent X-ray, CT plain scan, three-dimensional reconstruction and MRI examination to evaluate the stability of the implants and fusion rate before 3 days and 1, 3, 6, 12 and 18 months after operation., Results: All patients were followed up, and the duration ranged from 12 to 18 months. The operation time of single-segment fusion was (192.3±22.7) min, and that of double-segment fusion was (272.5±24.7) min. The estimated intraoperative bleeding volume was less than 50 ml per segment, and no blood transfusion was performed in all patients. The VAS improved from preoperative 7.4±1.1 to postoperative 2.3±0.8 ( t =-19.65, P <0.000 5). The ODI improved from preoperative (41.2±3.3)% to the final follow-up (12.3±2.5)%( t =-35.76, P <0.000 5). Postoperative complications occurred in 4 cases, and contralateral radicular symptoms occurred in 2 cases. After contralateral foraminoscopic decompression, the symptoms were completely alleviated. One case had neurological symptoms related to percutaneous screw placement, and the symptoms were alleviated after removal of the lateral screw rod internal fixation. The other cases had surgical incision infection and improved after debridement and suture. At the latest follow-up, no displacement or loosening of the fusion cage and screw rod system occurred in all patients, and 14 cases showed signs of fusion., Conclusions: PT-Endo-LIF is a minimal invasive, safe and efficient surgical procedure for treatment of degenerative lumbar disease. Nevertheless, the long-term results still need to be confirmed by a multi-center and lagre sample follow-up study., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© 2019 by the China Journal of Orthopaedics and Traumatology Press.)

Surface water samples were collected in the middle reaches of the Yellow River (Weinan-Zhengzhou section) and all 28 perfluoroalkyl and polyfluoroalkyl substance (PFAS) levels were measured using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The results show that the levels of PFASs in the water and particle phase are 18.4-56.9 ng·L -1 and 26.8-164 ng·g -1 , respectively. Perfluorohexanoic acid (PFHxA) in the water and particle phases is the main pollutant, accounting for 27% and 16% of the total concentrations, respectively, and 3H-perfluoro-3-[(3-methoxy-propoxy)-propanoate] acid (ADONA) and chlorinated polyfluorinated ethersulfonic acids (6:2 and 8:2 Cl-PFESA) were detected in the particle phase, indicating that the use of PFAS alternatives gradually increases. The lg K d of PFASs between the water and particle phase ranges from 2.95±0.553 (PFPeA) to 3.85±0.237 (8:2 FTUCA)and the adsorption of fluorotelomer carboxylic acids (FTCAs) and fluorotelomer unsaturated carboxylic acids (FTUCAs) on particulate matter increases with increasing of carbon chain length. Perfluoroalkane sulfonic acids (PFSAs) are more easily adsorbed by particulate matter than perfluoroalkyl carboxylic acids (PFCAs). The fluxes of PFASs in the Weinan-Zhengzhou section of the Yellow River show a decrease at first and then increase, indicating that this section receives pollution inputs from the upstream and tributaries. In addition, the results show that the fluxes of PFASs in the water phase are greater than those in the particle phase.

The water inrush should been rapidly and accurately identified during preventing coalmine water inrush. The laser induced fluorescent (LIF) spectrum technology provides a new method to identify water inrush with the characteristics of high sensitivity, quick and accurate monitoring. In order to identify water inrush, this paper introduces the spectrum technology of LIF to obtain water inrush fluorescence spectra data. The spectral preprocessing methods of Savitzky-Golay(SG) and Multiplicative Scatter Correction (MSC) have been used to eliminate noise spectra in collecting process. Principal component analysis (PCA) extracts feature information, for SG reprocessing data, when the number of principal component is 3, the cumulative contribution rate can reach 99.76 percent. This method has largely retained the information of original data. This paper chooses the classification model with 3 layers BP neural network, constructing by different training and testing sets. The classification model with SG preprocessing has achieved accurate identification, however, appeared few false identification for MSC and original data. The result shows that SG preprocessing is better than MSC. Research results show that the classification model with PCA and BP neural network can effectively identify coalmine water inrush, and have the strong self-organizing, self-learning ability.

Objective: To diagnose and treat the first imported active case of Plasmodium knowlesi infection in China., Methods: The clinical information of the patient was collected. Microscopy of blood smear was conducted after Giemsa staining. Genomic DNA was extracted from blood, and PCR was conducted to amplify rDNA. The PCR products were sequenced and analyzed with BLAST, Results: The patient returned from a one-week tour in a tropical rain forest in Malaysia. The first disease attack occurred in Guangzhou on Oct. 16, 2014, with fever, shivering and sweating. The patient was initially diagnosed as malaria and hospitalized on Oct. 26, 2014. Microscopic observation revealed typical forms of P. knowlesi in blood smear. The red blood cells became enlarged, with big trophozoites appearing as a ring with dual cores and dark brown malaria pigment. The trophozoites were slightly bigger and thicker than P. falciparum. The schizont had 6-8 merozoites, with obvious brown malaria pigment. PCR resulted in a specific band of 1 099 bp. BLAST analysis showed that the sequence of the PCR product was 99% homologous to P. knowlesi (acession No. AM910985.1, L07560.1 and AY580317.1). The patient was diagnosed as P. knowlesi infection, and was then given an 8-day treatment with chloroquine and primaquine, together with dihydroartemisinin piperaquine phosphate tablet. The patient was discharged after recovery on Oct. 28, 2014., Conclusion: According to the clinical symptoms, epidemiological history and laboratory test, the patient has been confirmed as P. knowlesi infection. It may also be the first active case of knowlesi malaria reported in China.

Rapid source identification of mine water inrush has great significance for early warning and rescuing after the mine water inrush. Conventional method taking the concentration of ions as the discriminant factor takes such a long time that a method of rapid source identification of mine water inrush is in urgent need. This method is combined with Laser induced fluorescence (LIF) technology and Partial Least Squares-Discriminant Analysis (PLS-DA) algorithm. In the experiment, 405 nm laser was used to excite the water and 100 groups of fluorescence spectrum from 5 different aquifer of the mine were obtained. According to the spectra curve features, the data was compressed to obtain proper spectral data. 15 groups of spectrum of each water inrush samples were applied, with a total of 75 groups of spectrum as the prediction set while the rest of 25 groups of spectrum as the test set. To verify the experimental result, an experimental model was built with soft independent modeling of class analogy (SIMCA) to compare with PLS-DA. The result shows that the fluorescence spectra of different aquifer water samples is of great difference, without any pre-treatment, the PLS-DA algorithm based on the PLS model has higher modeling accuracy compared with SIMCA algorithm, which reaches to 100%, the validation results and the correlation of separation of variables are both more than 0.951, the RMSECV and RMSEP are both less than 0.123, using the model to identify the 5 water samples of test set, the accuracy are up to 100%.

Rapid identification and classification of mine water inrush is important for flood prevention work underground. This paper proposed a method of KNN combined with PCA identification of water inrush in mine with the laser induced fluorescence spectrum with an immersion probe laser into water samples. The fluorescence spectra of 4 kinds of water samples were obtained. For each set of data preprocessing, the processed data in each sample from 15 sets of data as the training setwith a total of 60 groups. The other 20 groups were used as the prediction set. The data were processed by principal component analysis (PCA), and then the KNN algorithm was used to classify and identify the principal component analysis. During the experiment, the pretreatment method in the principal component number is 2 while the correct rate has reached 100% by KNN classification algorithm.

Rapid source identification of mine water inrush is of great significance for early warning and prevention in mine water hazard. According to the problem that traditional chemical methods to identify source takes a long time, put forward a method for rapid source identification of mine water inrush with laser induced fluorescence (LIF) technology and soft independent modeling of class analogy (SIMCA) algorithm. Laser induced fluorescence technology has the characteristics of fast analysis, high sensitivity and so on. With the laser assisted, fluorescence spectrums can be collected real-time by the fluorescence spectrometer. According to the fluorescence spectrums, the type of water samples can be identified. If the database is completed, it takes a few seconds for coal mine water source identification, so it is of great significance for early warning and post-disaster relief in coal mine water disaster. The experiment uses 405 nm laser emission laser into the 5 kinds of water inrush samples and get 100 groups of fluorescence spectrum, and then put all fluorescence spectrums into preprocessing. Use 15 group spectrums of each water inrush samples, a total of 75 group spectrums, as the prediction set, the rest of 25 groups spectrums as the test set. Using principal component analysis (PCA) to modeling the 5 kinds of water samples respectively, and then classify the water samples with SIMCA on the basis of the PCA model. It was found that the fluorescence spectrum are obvious different of different water inrush samples. The fluorescence spectrums after preprocessing of Gaussian-Filter, under the condition of the principal component number is 2 and the significant level α = 5%, the accuracy of prediction set and testing set are all 100% with the SIMCA to classify the water inrush samples.

Objective: To explore the methylation level of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) gene promoter region in mitochondria of trophoblasts incubated with long-chain fatty acids and the time-effect of methylation modification., Methods: Primary human trophoblast cells and HTR8/Svneo cells were incubated with free fatty acids of various lengths. Long-chain free fatty acids (LC-FFA) was experimental group, short-chain fatty acids (SC-FFA) and medium-chain fatty acids (MC-FFA) were control groups, and blank control was without free fatty acid. Collecting cells and extract DNA at 24, 48 and 72 h incubation respectively. Predicted CpG island location access to 2 000 bp DNA sequences upstream of the transcription start site of LCHAD gene. We designed methylation detection sites and primer originally. Methylation of CpG sites in LCHAD gene promoter region were detected by MassARRAY and analyzed statistically., Results: (1) We detected methylation of 65% (11/17) CpG sites, including 8 single sites and 3 composite sites, in ampliconic sequences. These CpG sites were at positions: -984, -960, -899, -853, -811, -796, -774, -727, -615, -595, -579, respectively. In different groups methylation level and changes of every site showed differences with the most significant changes at -899 site. (2) Methylation of CpG island in LCHAD gene promoter region: ① Methylation of CpG island in LC-FFA and MC-FFA groups showed rising trend with the time: Methylation level of LC-FFA group at 72 h (0.55±0.08) was significantly higher than that of 48 h (0.35±0.12) and 24 h (0.31±0.04) (P<0.05). Methylation level of MC-FFA group at 72 h (0.44±0.05) was significantly higher than that of 24 h (0.31±0.04) (P<0.05). ② Methylation of CpG island in LCHAD gene promoter region in different groups at different times: Methylation level of LC-FFA group at 72 h was significantly higher than that of the other two groups at 72, 48 and 24 h (P<0.05). (3) Methylation of 11 CpG sites in LCHAD gene promoter region in different groups at 72 h: Methylation level of -899 site in LC-FFA and MC-FFA groups were significantly higher than that of other sites (P<0.05). (4) Methylation level of -899 site in LCHAD gene promoter region in LC-FFA group showed rising trend with the time: (72 h (0.34±0.15), 48 h (0.14±0.05) and 24 h (0.10±0.02), P<0.05). Methylation level of LC-FFA group at 72 h was significantly higher than that of the other two groups at 72, 48 and 24 h (P<0.05)., Conclusions: Methylation modification effect on LCHAD gene promoter region in trophoblast cells incubated with long-chain fatty acids is more significant than with medium-chain and short-chain fatty acids and shows obvious time-effect as incubation time prolonged. The changes at -899 site dominate the degree of methylation in LCHAD gene promoter region.

Objective: To investigate the changes of fatty acid oxidase in the placenta of preeclampsia cases with different clinical features, and the relationship with oxidative stress and inflammatory response. To study the correlation of serum free fatty acid (FFA) and triglycerides (TG) level in early second trimester with the molecular changes of the long-chain fatty acid oxidase in the third trimester., Methods: This was prospective cohort study, in which cases with singleton pregnancies who archived in Haidian Maternal and Children's Hospital, Beijing, from January 1st 2012 to May 31st, with regular prenatal care were included. Doppler ultrasound was used for screening for the presence of early diastolic notch of uterine artery at 22-24 weeks of gestation. All the 101 cases with the early diastolic notch of uterine artery were included as the notch group, and 377 cases without the early diastolic notch of uterine artery were included as the non-notch group. The perinatal outcomes and the incidence of hypertensive disorders in pregnancy of the two groups were observed. The serum level of FFA and TG was tested, and the mRNA and protein expression of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD), P47-phox subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, p38 mitogen-activated protein kinase a (p38MAPK-α) and cyclooxygenase-2 (COX-2) were detected using real-time quantitative PCR and western blot. The relationship between serum level of FFA and TG and the mRNA and protein expression of LCHAD, NADPH P47-phox, p38MAPK-α and COX-2 of the placental tissue specimens were analyzed., Results: (1) In the notch group, there were 9 cases of early-onset preeclampsia, 15 cases of late-onset preeclampsia and 10 cases of gestational hypertension;and there were 8 cases of late-onset preeclampsia and 18 cases of gestational hypertension in the non-notch group. 15 cases with normal blood pressure in each group were randomly selected as the control group. (2)The serum level of TG of cases of early-onset preeclampsia, late-onset preeclampsia and gestational hypertension in the notch group were (2.0 ± 0.8), (1.8 ± 0.6)and (1.9 ± 0.7)mmol/L, and that of FFA were(0.68 ± 0.26), (0.52 ± 0.10) and (0.52 ± 0.17)mmol/L, respectively. The serum level of TG of cases of late-onset preeclampsia and gestational hypertension in the non-notch group were (1.6 ± 0.6) and (1.4 ± 0.4)mmol/L, and that of FFA were (0.49 ± 0.11) and (0.48 ± 0.05)mmol/L, respectively. The serum level of TG and FFA in the control group were (1.4 ± 0.5) and (0.52 ± 0.06)mmol/L, respectively. The TG level of the notch group was higher than that of the control group, and the difference was statistically significant (P < 0.05). The FFA level of the early-onset preeclampsia in the notch group was higher than that of late-onset preeclampsia in the notch group, late-onset preeclampsia in the non-notch group and the control group, and the difference was statistically significant (P < 0.05). (3) The mRNA expression of LCHAD in the placenta of early-onset preeclampsia in the notch group was significantly lower than that of the late-onset preeclampsia in the notch group, late-onset preeclampsia in the non-notch group and the control group (P < 0.01). The mRNA expression of NADPH P47-phox of the early-onset preeclampsia in the notch group were significantly higher than that of late-onset preeclampsia in the notch group, late-onset preeclampsia in the non-notch group and the control group (P < 0.01). The mRNA expression of p38MAPK-α of the early-onset preeclampsia in the notch group were significantly higher than that of late-onset preeclampsia in the notch group, late-onset preeclampsia in the non-notch group and the control group (P < 0.01). The mRNA expression of COX-2 of the early-onset preeclampsia in the notch group were significantly higher than that of late-onset preeclampsia in the notch group, late-onset preeclampsia in the non-notch group and the control group (P < 0.01). (4)The protein expression of LCHAD in the placenta of early-onset preeclampsia in the notch group, late-onset preeclampsia in the notch group and gestational hypertension in the notch group were significantly lower than that of the control group (P < 0.01); and the protein expression of LCHAD in the placenta of early-onset preeclampsia in the notch group was significantly lower than that of late-onset preeclampsia in the non-notch group (P < 0.01). The protein expression of NADPH P47-phox in the placenta of early-onset preeclampsia in the notch group was significantly higher than that of late-onset preeclampsia in the non-notch group and control group (P < 0.05). The protein expression of p38MAPK-α in the placenta of early-onset preeclampsia in the notch group was significantly higher than that of late-onset preeclampsia in the notch group, late-onset preeclampsia in the non-notch group and control group (P < 0.01). The protein expression of COX-2 in the placenta of early-onset preeclampsia in the notch group, late-onset preeclampsia in the notch group, gestational hypertension in the notch group, late-onset preeclampsia in the non-notch group, and gestational hypertension in the non-notch group, were significantly higher than that of control group (P < 0.01). (5)The blood concentration of maternal FFA in the early-onset preeclampsia in the notch group was significantly negatively correlated with the mRNA and protein expression of placental LCHAD (r = -0.810, -0.932, P < 0.01). There was no correlation between maternal TG level and the mRNA and protein expression of placental LCHAD in each group(P > 0.05). (6)The mRNA expression of placental LCHAD in the early-onset preeclampsia in the notch group was significantly negatively correlated with the mRNA expression of placental NADPH P47-phox and COX-2 (r = - 0.877, -0.762, P < 0.05). The mRNA expression of placental LCHAD in the control group was significantly negatively correlated with the mRNA expression of placental COX-2 (r = -0.565, P < 0.01). The protein expression of placental LCHAD in the early-onset preeclampsia in the notch group was significantly negatively correlated with the protein expression of NADPH P47-phox (r = -0.818, P < 0.01). The protein expression of placental LCHAD in the control group was significantly negatively correlated with the protein expression of COX-2 (r = -0.502, P < 0.01)., Conclusions: The placental mRNA and protein expression of long-chain fatty acid oxidation enzymes were different in different clinical features of preeclampsia, which were reduced more obviously in the early-onset preeclampsia in the notch group than that of the late-onset preeclampsia in the notch group, and were negatively correlated with the elevated serum FFA level, significantly enhanced oxidative stress and inflammatory response, but with no correlation with serum TG level.

Objective: To investigate the effect of anti-EGFR monoclonal antibody on the chemosensitivity of human colon cancer cells and explore the possible molecular mechanism., Methods: The inhibitory effect of irinotecan (CPT-11), oxaliplatin (L-OHP) and fluorouracil (5-Fu), used alone or in combination with anti-EGFR monoclonal antibody, on the proliferation of LoVo cells in vitro was assessed by MTT assay. The expressions of PI3K and Akt protein in the treated cells were examined by Western blotting, and their mRNA expressions were detected by RT-PCR., Results: Both h-R3 and C-225 treatments significantly increased the chemosensitivity of LoVo cells to irinotecan and oxaliplatin. 5-Fu and h-R3 coadministered showed a synergistic effect on the cells, but 5-Fu and C-225 had an antagonistic action. Treatment with C-225 or h-R3 resulted in lowered expressions of PI3K and Akt in LoVo cells., Conclusion: Anti-EGFR monoclonal antibody can increase the chemosensitivity of human colon cancer cells to most chemotherapeutic drugs, and such effect might be attributed to the blocking of PI3K/Akt signaling pathway by these antibodies.

In order to control the ion density and energy distribution in the vicinity of plasma sheath independently, the inductively coupled plasma and its glow discharge mechanism in the vicinity of plasma sheath were studied by means of optical emission spectroscopy (OES) under different RF power, different discharge and different substrate DC bias voltage. It was shown that the ion density is higher and the electron temperature is lower in the vicinity of inductively coupled plasma sheath according to the ionic line and atomic line. With changing the discharge pressure and RF power, the spectral characteristics analysis shows that the ion density in the vicinity of plasma sheath linearly increases with the RF power and rises with the pressure under the low pressure. The atomic spectral intensity of low excitation states increases rapidly. The atomic spectral intensity of high excitation states rises slowly and the intensity of ion spectrum increases not obviously. By applying the DC bias voltage to substrate, the intensity of emission spectroscopy was analyzed. The result shows that the intensity of spectra rises with the increase in positive bias voltage, while first reduces then increases with the increase in negative bias voltage, and is the weakest in the case of DC bias at -30 V. This shows that the fast ions and the electrons are the main source of energy for Ar ionization and excitation.

Aim: To investigate the reversion of multidrug resistance of drug-resistant hepatocellular carcinoma (HCC) cell line BEL-7402/FU by sorafenib and the possible mechanisms., Methods: Flow cytometry was applied to detect the expression of rhodamine 123 (Rho123), immunohistochemistry was applied to observe the expression of P-glycoprotein (P-gp) on the cell membrane, the fluorescence quantitative PCR assay was applied to determine the changes of the multidrug-resistant gene mdr1 mRNA level and the Western blot assay was applied to test the changes of the expression level of the mdr1 gene product P-gp., Results: After 4 micromol/L treatment by sorafenib, Rho123 accumulation was increased by BEL-7402/FU and exocytosis was slowed down, which evidently reduced the expression of cell surface P-gp; the mdr1 mRNA level was reduced by 35.4% compared to its level prior to drug administration; the expression level of the mdr1 gene product P-gp was significantly suppressed, 14.3% fewer than that of BEL-7402/FU cells., Conclusion: Sorafenib can inhibit the expression of the mdr1 gene product P-gp and increase the intracellular concentration of chemotherapeutic drugs, so as to reverse the multidrug resistance of HCC cells.

Objective: To investigate the clinical significance of vascular endothelial growth factor (VEGF) levels in serums of colorectal cancer patients at stage IV., Methods: Using enzyme linked immunosorbent assay (ELISA) to detect the VEGF levels in serums of 45 colorectal cancer patients at stage IV, and 20 healthy served as normal control., Results: The mean concentration of VEGF in 45 colorectal cancer patients at the 7 day after operation were significantly lower than that before operation (P<0.01). The mean concentration of VEGF in the patients who benefit from bevacizumab showed no statistical difference from the levels of who did not benefit (P=0.554)., Conclusion: The VEGF levels in colorectal patients at stage IV are lowed as the load of tumor decrease. The circulating levels of VEGF seem not predict the response to bevacizumab in colorectal cancer patients at stage IV.

Raman lidar is an important tool for the detection of atmosphere pollution, and inversion for lidar returns is an important process. The key for inversion is to get transmission exponential function exp [integral of 0 (R) [alpha(lambda1, z) - alpha(lambda2, z)]]. Three methods with extinction coefficient as the center are presented. First, 532 nm atmospheric extinction coefficient was used to indirectly obtain alpha(lambda1, z) and alpha(lambda2, z). This method has been used generally by people. Two new methods were proposed: 1, reference gas with approximate Raman wavelength is used so that alpha(lambda1, z) = alpha(lambda2, z). 2, Mie-Rayleigh scattered return with wavelength lambda1 or lambda2 is used to compute exp [integral of 0 (R) [alpha(lambda1, z) - alpha(lambda2, z)]].

Objective: To analyze the particularities of diagnosis and treatment of acute cerebral stroke secondary to polycythemia vera (PV)., Methods: To track and evaluate the clinical parameters, the manifestations of CT/MRI, the data of laboratory examinations, the therapeutic responses and the prognosis of acute cerebral stroke secondary to PV. Twenty-two cases of PV with initial presentation as acute stroke were analyzed., Results: (1) 55.0% of the patients with stroke as the initial presentation of to PV had multiple lacuna infarction. (2) 37.5% of the patients had a temporary symptom aggravation after receiving a therapeutic regimen of blood-letting and chemotherapy, whereas, the stroke symptoms improved and became stable when treated with blood-letting combined with hemodilution and chemotherapy simultaneously. (3) Six cases received homoharringtonine treatment and all of them reached complete remission (CR). However, 3 of them showed ST segment and T-wave changes in electrocardiogram and 2 of them had bone marrow depression. Four cases received arsenic trioxide and obtained CR, but the relapse rate reached 50.0%. Nine cases were treated with hydroxycarbamide and all of them obtained CR., Conclusions: (1) Stroke secondary to PV should be treated with stroke regimen as well as PV therapy, and hydroxycarbamide might have stable benefit and few side effects. (2) Hematocrit assay should be used as a routine item in stroke patients with frequently relapsed.

The fluorescence spectra of dissolved organic matter (DOM) in several types of water samples in combination with laser-induced fluorescence (LIF) measurements were measured in the laboratory, and the spectral characteristics of DOM were analysed. The curve of normalized fluorescence intensity against corresponding concentration of humic acid is showed. The results demonstrate the possibilities of water quality monitoring based upon fluorescence spectral characteristics of DOM by means of LIF method.

Objective: To investigate the effects of protein tyrosine kinase (PTK), protein tyrosine phosphatase (PTP) and protein kinase C (PKC) on apoptosis and observe the changes of cytosolic calcium ([Ca(2+)]i) of arsenic trioxide (As2O3) treated human leukemia cells NB4 and cortex neurons., Methods: [Ca(2+)]i of NB4 cells and cortex neurons was probed with Fluo-3/AM, its changes were assayed with laser confocal microscopy in real-time after As2O3 treatment at different concentrations, the effects of PTK and PTP and the activation of PKC on these changes with confocal microscopy and phosphorus radioisotope assay. DNA ladders of NB4 cells and cortex neurons after exposed to As2O3 were observed., Results: As2O3 at 1 micromol/L could remarkably increase the [Ca(2+)]i of NB4 cells but had no effects on neurons. Vanadate, a kind of PTP inhibitor, could promote the increase of [Ca(2+)]i treated by 2, 5, 10 micromol/L As2O3 in a dose-dependent manner. The mean total increase rates at 240 seconds after exposed to As2O3 at different concentrations were (6.5 +/- 2.3)%, (21.7 +/- 2.1)%, (49.2 +/- 2.5)% for NB4 cells, and (6.7 +/- 2.1)%, (19.4 +/- 2.5)%, (52.3 +/- 2.7)% for cortex neurons, respectively. Genistein, a kind of PTK inhibitor, could decrease the increase of [Ca(2+)]i treated by 2, 5, 10 micromol/L As2O3 in a dose-dependent manner. The mean total inhibited rates at 240 seconds after As2O3 treatment at different concentrations were (6.7 +/- 2.9)%, (25.6 +/- 2.5)%, (52.2 +/- 3.5)% for NB4 cells, and (7.8 +/- 3.1)%, (18.1 +/- 2.8)%, (51.3 +/- 3.3)% for cortex neurons, respectively. The activation of PKC began to increase as exposed to As2O3 at 1 micromol/L for 3 h, and kept rising continuously in NB4 cells and at 24 h DNA ladders emerged. However, none of the above results was found in human cortex neurons, but when exposed to 2 micromol/L As2O3, the activation of PKC and DNA ladders did emerge in neurons., Conclusions: The phosphorylation and dephosphorylation of PTK and PTP participated in nonspecific apoptosis signal transduction pathway related to As2O3, and accompanied with PKC activation. The [Ca(2+)]i elevation was closely related to increased PKC activation. There existed difference in dose tolerances to As2O3 between NB4 cell and cortex neurons.

Objective: To assess the effectiveness and security of two arsenic trioxide (As(2)O(3)) administration methods in treatment of acute promyelocytic leukemia (APL)., Methods: Forty-eight APL cases were treated with As(2)O(3) with the total daily dosage of 0.16 mg/kg that was divided into two equal doses diluted in 250 ml of 5% glucose given twice in the morning and evening respectively by intravenous infusion' at a speed of 8 drops/min with an interval of 2-3 hours. Forty-eight sex- and age-matched APL cases were treated with As(2)O(3) with the same total daily dosage of 0.16 mg/kg given according to the routine method: infused intravenously once a day with a duration of at most 2 hours. Serum was collected at different time points to examine the arsenic concentration. The remission rate and side effects were observed., Results: The remission rate was 93.8% in the patients treated by the new method, and was 83.3% in the patients treated by the routine method 28 days after the treatment. The lasting duration of effective arsenic level was at least 18.4 +/- 3.3 hours in the new method group, and was 9.4 +/- 1.6 hours in the routine method group. The average time from the initiation of treatment to complete remission (CR) in the new method group was 26.4 +/- 2.4 days, and was 35.7 +/- 4.8 days in the routine method group. No late liver functional lesion and bone marrow depression was found in the two groups during the 6 months followed up., Conclusion: The 'multi-times and slowing intravenous infusion' method relieves the side effects of As(2)O(3) treatment, increases the CR rate in treatment of APL.

Objective: To investigate the association between subacute combined degeneration (SCD) and vitamin B(12) (VB(12)) deficiency and megaloblastic anemia (MA)., Methods: The serum level of VB(12), severity of anemia and lesions in CNS were analysed in 36 cases diagnosed as SCD. In addition, MRI neuro-electrophysiologic examination and CSF myelin basic protein (MBP) concentration were monitored dynamically. The prognosis of SCD was evaluated in relation to the time of the initiation of therapy., Results: Average ferrohemoglobin level in patients was (77.1 +/- 11.2) g/L and the average blood serum level of VB(12) was (87.0 +/- 21.4) ng/L before treatment with an abnormality rate of 47.2%. However, there was no linear correlation between the severity of lesions in CNS and ferrohemoglobin level or level of serum VB(12) (correlation coefficient: r = -0.1917, 0.0926, P > 0.5; r = 0.207, 0.101, P > 0.5, respectively). The comprehensive abnormal rate of evoked potential was 100%, which might occur prior to the clinical symptoms of SCD. The abnormal rate of MRI was 71.4%, and some lesions could diminish or disappear after treatment. The MBP levels in CSF were (3.96 +/- 1.66) ng/L, and (2.25 +/- 1.66) ng/L before and 3 months after the treatment. No significant improvement of symptoms and signs were seen when the treatment was initiated 6 months after the diagnosis., Conclusion: SCD is associated with VB(12) deficiency and often accompanied by MA, but there is no linear correlation. Lesions of SCD in spinal cord or brain can be demonstrated in MRI. Evoked potential is critical for early diagnose and identification of silent cases of SCD. The level of MBP in CSF can reflect the severity of the lesion and prosthetic state of myelin sheath. Early diagnosis and treatment play an important role in decreasing the degree of the permanent dysfunction of CNS in SCD.

Objective: To investigate cardiac effects of arsenic trioxide (As(2)O(3)) at conventional dosage in acute promyelocytic leukemia (APL) patients., Methods: The basical heart rate, electrocardiograph, plasma As(2)O(3) concentration of APL patients were dynamically monitored. The action potential duration and current of I(Ca-L) in guinea pig cardiac ventricular myocytes were assayed by patch clamp technique, and the elevated cytosolic [Ca(2+)]i of guinea pig ventricular myocytes induced by As(2)O(3) by laser confocal microscopy., Results: Approximately 52.5% - 35% of 40 APL patients manifested poor cardiac effects of different degree when As(2)O(3) intravenous infused at conventional doses in the initial 1 or 2 weeks with fast heart rate or prolonged QT interval. As(2)O(3) at concentration of 1, 2, 5 micro mol/L prolonged action potential duration from (563.0 +/- 55.8) ms to (737.7 +/- 131.7), (842.4 +/- 115.6) and (1103.2 +/- 96.3) ms respectively (P < 0.05, P < 0.01, P < 0.01), and increased I(Ca-L) of guinea pig cardiac ventricular myocytes as well as the respectively cytosolic [Ca(2+)]i. Calcium channel blocking agent can cut-out the effect., Conclusion: As(2)O(3) intravenous infusion at conventional doses can cause tachycardia and prolong QT interval. The probable mechanism might be that As(2)O(3) affects the ion channels and cytosolic calcium.

Objective: To study the cardiac toxicity of arsenic trioxide (As(2)O(3))., Methods: To investigate and analyze the probable mechanisms of cardiac toxicity of As(2)O(3) by dynamic monitoring of clinical manifestations, basal cardiac rate and electrocardiographic data of acute promyelocyte leukemia (APL) patients during As(2)O(3) therapy. The instant change of the action potential, the I(Ca-L) and I(k) of single cardiac myocyte of guinea pig was also observed with patch clamp dynamically., Results: Approximately 71.4% of the 28 cases of APL showed cardiac toxic reaction in different degree in the first week after As(2)O(3) intravenous infusion in general dose, mainly expressing rapid heart rate or prolonged QT interval. As(2)O(3) could prolong the action potential duration from (563.0 +/- 55.8) ms to (737.7 +/- 131.7) ms (P < 0.05) and increased the I(Ca-L) and I(k) of single cardiac myocyte of guinea pig in vitro., Conclusion: As(2)O(3) intravenous infusion in general therapeutic dose can cause tachycardia and prolong QT interval in some of the APL patients. The probable mechanism of these side-effects may be due to instant involvement of ionic channel of cardiac myocyte.