OBJECTIVES: We propose a sparse-view cone-beam CT reconstruction algorithm based on bidirectional flow field guided projection completion (BBC-Recon) to solve the ill-posed inverse problem in sparse-view cone-beam CT imaging. METHODS: The BBC-Recon method consists of two main modules: the projection completion module and the image restoration module. Based on flow field estimation, the projection completion module, through the designed bidirectional and multi-scale correlators, fully calculates the correlation information and redundant information among projections to precisely guide the generation of bidirectional flow fields and missing frames, thus achieving high-precision completion of missing projections and obtaining pseudo complete projections. The image restoration module reconstructs the obtained pseudo complete projections and then refines the image to remove the residual artifacts and further improve the image quality. RESULTS: The experimental results on the public datasets of Mayo Clinic and Guilin Medical University showed that in the case of a 4-fold sparse angle, compared with the suboptimal method, the BBC-Recon method increased the PSNR index by 1.80% and the SSIM index by 0.29%, and reduced the RMSE index by 4.12%; In the case of an 8-fold sparse angle, the BBC-Recon method increased the PSNR index by 1.43% and the SSIM index by 1.49%, and reduced the RMSE index by 0.77%. CONCLUSIONS The BBC-Recon algorithm fully exploits the correlation information between projections to allow effective removal of streak artifacts while preserving image structure information, and demonstrates significant advantages in maintaining inter-slice consistency.
Algorithms ; Cone-Beam Computed Tomography/methods* ; Image Processing, Computer-Assisted/methods* ; Humans

Objective To propose a CT truncated data reconstruction model(DDTrans)based on projection and image dual-domain Transformer coupled feature learning for reducing truncation artifacts and image structure distortion caused by insufficient field of view(FOV)in CT scanning.Methods Transformer was adopted to build projection domain and image domain restoration models,and the long-range dependency modeling capability of the Transformer attention module was used to capture global structural features to restore the projection data information and enhance the reconstructed images.We constructed a differentiable Radon back-projection operator layer between the projection domain and image domain networks to enable end-to-end training of DDTrans.Projection consistency loss was introduced to constrain the image forward-projection results to further improve the accuracy of image reconstruction.Results The experimental results with Mayo simulation data showed that for both partial truncation and interior scanning data,the proposed DDTrans method showed better performance than the comparison algorithms in removing truncation artifacts at the edges and restoring the external information of the FOV.Conclusion The DDTrans method can effectively remove CT truncation artifacts to ensure accurate reconstruction of the data within the FOV and achieve approximate reconstruction of data outside the FOV.

Objective To propose a CT truncated data reconstruction model(DDTrans)based on projection and image dual-domain Transformer coupled feature learning for reducing truncation artifacts and image structure distortion caused by insufficient field of view(FOV)in CT scanning.Methods Transformer was adopted to build projection domain and image domain restoration models,and the long-range dependency modeling capability of the Transformer attention module was used to capture global structural features to restore the projection data information and enhance the reconstructed images.We constructed a differentiable Radon back-projection operator layer between the projection domain and image domain networks to enable end-to-end training of DDTrans.Projection consistency loss was introduced to constrain the image forward-projection results to further improve the accuracy of image reconstruction.Results The experimental results with Mayo simulation data showed that for both partial truncation and interior scanning data,the proposed DDTrans method showed better performance than the comparison algorithms in removing truncation artifacts at the edges and restoring the external information of the FOV.Conclusion The DDTrans method can effectively remove CT truncation artifacts to ensure accurate reconstruction of the data within the FOV and achieve approximate reconstruction of data outside the FOV.

Objective To evaluate the potential risk of transmission of angiostrongyliasis by common freshwater snails in Dali Bai Autonomous Prefecture, Yunnan Province, so as to provide insights into local surveillance of angiostrongyliasis. Methods Common freshwater snails were collected from Dali Bai Autonomous Prefecture, Yunnan Province from March to April, 2020, and identified and bred in laboratory. SD rats were infected with third-stage larvae of Angiostrongylus cantonensis that were isolated from commercially available Pomacea canaliculata snails in Dali Bai Autonomous Prefecture, and freshwater snails were infected with the first-stage larvae of A. cantonensis that were isolated from the feces of SD rats 39 days post-infection at room temperature. The developmental process and morphological characteristics of worms in hosts were observed, and the percentages of A. cantonensis infections in different species of freshwater snails were calculated. Then, SD rats were infected with the third-stage larvae of A. cantonensis that were isolated from A. cantonensis-infected freshwater snails, and the larval development and reproduction was observed. Results More than 3 000 freshwater snail samples were collected from farmlands, ditches and wetlands around Erhai Lake in Dali Bai Autonomous Prefecture, and Cipangopaludina chinensis, P. canaliculata, Parafossarulus striatulus, Oncomelania hupensis robertsoni, Galba pervia, Physa acuta, Radix swinhoei, Assiminea spp., Tricula spp. and Bellamya spp. were morphologically identified. A total of 105 commercially available P. canaliculata snails were tested for A. cantonensis infections, and 2 P. canaliculata snails were found to be infected with A. cantonensis, in which the third-stage larvae of A. cantonensis were isolated. Ten species of freshwater snails were artificially infected with the third-stage larvae of A. cantonensis, and all 10 species of freshwater snails were found to be infected with A. cantonensis, with the highest positive rate of A. cantonensis infections in Bellamya spp. (62.3%, 137/204), and the lowest in C. chinensis (35.5%, 11/31). After SD rats were infected with the third-stage larvae of A. cantonensis isolated from different species of freshwater snails, mature adult worms of A. cantonensis were yielded. Conclusions Multiple species of freshwater snails may serve as intermediate hosts of A. cantonensis under laboratory conditions in Dali Bai Autonomous Prefecture of Yunnan Province. Further investigations on natural infection of A. cantonensis in wild snails in Dali Bai Autonomous Prefecture seem justified.

Objective To investigate the reliability and feasibility of spectral entropy in evaluate the effectiveness of analgesic sedation in patients with ischemic stroke.Methods A total of 64 patients with acute ischemic stroke admitted to Hongqi Hospital Affiliated to Mudanjiang Medical University from July 2021 to November 2022 were selected as study objects,and the included patients were divided into control group and experimental group according to random number table method,with 32 cases in each group.Patients in control group adjusted analgesia and sedation regimen according to Richmond agitation-sedation scale(RASS)score and critical-care pain observation tool(CPOT)score.Patients in experimental group adjusted the analgesic and sedation regimen according to the results of spectral entropy.The vital signs,C-reactive protein(CRP),dose of sedative and analgesic drugs and incidence of adverse reactions were compared between two groups.The correlation between spectral entropy and RASS score and CPOT score was used Spearman correlation analysis.Results The spectral entropy values were positively correlated with the RASS score and CPOT score,respectively(r=0.719,0.556,P<0.001).There were no significant differences in mean arterial pressure and percutaneous arterial oxygen saturation between two groups at different time points(P>0.05).The heart rate at T3 in experimental group was significantly lower than that in control group(P<0.05).At T1,T2 and T3,CRP levels in experimental group were significantly lower than those in control group(P<0.05).The dosage of sufentanil and midazolam in experimental group were significantly lower than those in control group(P<0.05).The incidence of adverse reactions in experimental group was significantly lower than that in control group(12.50%vs.34.38%,χ2=4.267,P=0.039).Conclusion Spectral entropy can be used as an objective method to monitor the depth of analgesia and sedation in patients with ischemic stroke,and has a good correlation with RASS score and CPOT score,which can reduce the incidence of adverse reactions,effectively avoid stress reactions,and reduce the application of analgesia and sedation drugs.

Extremity vascular firearm injury (EVFI) which occurs in large quantities during wartime and is dispersed in peacetime, can result in acute hemorrhagic shock and compartment syndrome, thus seriously endangering the patients′ life. Compared with vascular trauma, vascular firearm injury not only damages the arteries easily, but also has a more severe damage and a poor prognosis. At present, most of relevant reports on the clinical diagnosis and treatment of EVFI in China are based on the treatment experience in Vietnam′s self-defense counterattack and lack subsequent technology, data and wartime echelon treatment. To this end, the authors discussed the epidemiological characteristics, diagnosis and treatment of EVFI by integrating the literature published since the Afghanistan and Iraq War, aiming to provide reference for the diagnosis and treatment of EVFI in China.

Objective To analyze the curative effect of acupuncture at Gongsun, Sifeng combined with visceral acupoint tapping in children with mesenteric lymphadenitis (type of gastrointestinal heat accumulation), and its influence on serum intestinal fatty acid-binding protein (I-FABP) and vasoactive intestinal peptide (VIP). Methods A total of 60 children with mesenteric lymphadenitis (type of gastrointestinal heat accumulation) were selected, and were divided into control group (n=30, conventional treatment combined with acupuncture at Gongsun and Sifeng acupoints) and study group (n=30, visceral acupoint tapping on the basis of the control group) according to the random number table method. The clinical efficacy, changes of main symptoms and signs were compared, and the expression levels of serum I-FABP and VIP were detected. Results The total effective rate of the study group was higher than that of the control group(P < 0.05). After 2 weeks of treatment, the serum I-FABP levels of the two groups were lower than that before treatment, and the serum I-FABP level of the study group was lower than that of the control group (P < 0.05). After 2 weeks of treatment, the serum VIP levels of the two groups were higher than that before treatment, and the serum VIP level of the study group was higher than that of the control group (P < 0.05). After 2 weeks of treatment, the improvement of main symptoms and signs in the study group was better than that in the control group (P < 0.05). Conclusion Acupuncture at Gongsun and Sifeng combined with visceral acupoint tapping can be used to treat children with mesenteric lymphadytis (gastrointestinal heat accumulation type), regulate and improve gastrointestinal function, adjust the level of serum I-FABP and VI, and relieve the main symptoms and signs of children, and can be used as an effective therapeutic method.

Objective:To analyze the types and distribution characteristics of elements in drinking water from endemic fluorosis areas with water improvement in Xi'an City, understand the relationship between fluoride and various elements, and conduct health risk assessment on potential high-risk elements.Methods:From May to June 2017, one endemic fluorosis area with water improvement (Gaoling District, Huyi District, Lintong District) was selected according to the northeast, the southwest and the due east directions of Xi'an City as the survey area. Sixteen endemic fluorosis villages were selected from each endemic area, and 2 water samples were collected from each endemic village to detect fluoride and 12 elements such as chromium, manganese, ferrum, copper, zinc, arsenic, selenium, molybdenum, cadmium, antimony, barium, and lead. Hygienic evaluation was conducted according to national standards, and the potential high-risk elements (arsenic, molybdenum) were assessed for health risk through the health risk assessment model recommended by the National Environmental Protection Agency of the United States.Results:The water samples from the endemic fluorosis areas in Xi'an City mainly contained seven elements: barium, ferrum, molybdenum, arsenic, zinc, manganese, and chromium. The content of copper and selenium was relatively low, while the content of cadmium, antimony, and lead was extremely low. The fluoride content in water samples from Gaoling District and Lintong District was relatively high, and the fluorine, arsenic, molybdenum elements was pairwise positively correlated ( P < 0.05). The molybdenum element in water samples from Lintong District exceeded 9.38% (3/32). The fluoride in the water samples of Huyi District was relatively low, and the arsenic, molybdenum elements was positively correlated ( r = 0.84, P < 0.001), and the arsenic element exceeded the standard by 25.00% (8/32). The main health risk of drinking water in endemic fluorosis areas with water improvement in Xi'an City was arsenic exposure, with children at a higher risk than adults, and the areas of Huyi District, Lintong District, and Gaoling District declined, the risk of cancer (CR) of Gaoling District was < 10 -4 and hazard quotient (HQ) was < 1. However, in the areas of Huyi District and Lintong District (except HQ of adults), there was a higher risk (CR > 10 -4, HQ > 1). Children in one endemic fluorosis village in Lintong District had a higher non carcinogenic risk of molybdenum (HQ > 1). Conclusions:The drinking water in endemic fluorosis areas with water improvement in Xi'an City mainly contains 7 elements, especially arsenic and molybdenum, which need to be regularly monitored. Some areas have high health risks of arsenic in water, and monitoring, management, and related epidemiological investigations need to be strengthened. At the same time, it is necessary to actively monitor other toxic and harmful substances that may be introduced during the water improvement process to prevent the occurrence of secondary health problems.

Humans ; Pulmonary Alveolar Proteinosis/radiotherapy* ; Small Cell Lung Carcinoma/radiotherapy* ; Lung ; Bronchoalveolar Lavage ; Lung Neoplasms/radiotherapy*

Angiostrongyliasis cantonensis is an emerging infectious disease in China. Snails are intermediate hosts of Angiostrongylus cantonensis and play a critical role in the transmission of angiostrongyliasis cantonensis. Detection of A. cantonensis in snails is an important part of epidemiological surveys. Currently, the rapid developments in the techniques for detection of A. cantonensis in snails facilitate the surveillance of angiostrongyliasis cantonensis and provide an important support for angiostrongyliasis cantonensis prevention and control. This review summarizes the advances in the techniques for detection of A. cantonensis in snails.