The G93A-SOD1 mice model and MRI diffusion as a preclinical tool to study amyotrophic lateral sclerosis （ALS）： ALS is a progressive neurological disease characterized primarily by the development of limb paralysis,...The G93A-SOD1 mice model and MRI diffusion as a preclinical tool to study amyotrophic lateral sclerosis （ALS）： ALS is a progressive neurological disease characterized primarily by the development of limb paralysis, which eventually leads to lack of control on muscles under voluntary control and death within 3–5 years. Genetic heterogeneity and environmental factors play a critical role in the rate of disease progression and patients display faster declines once the symptoms have manifested. Since its original discovery, ALS has been associated with pathological alterations in motor neurons located in the spinal cord （SC）, where neuronal loss by a mutation in the protein superoxide dismutase in parenthesis （mSOD1） and impairment in axonal connectivity, have been linked to early functional impairments. In addition,mechanisms of neuroinflammation, apoptosis, necroptosis and autophagy have been also implicated in the development of this disease. Among different animal models developed to study ALS, the transgenic G93A-SOD1 mouse has become recognized as a benchmark model for preclinical screening of ALS therapies. Furthermore, the progressive alterations in the locomotor phenotype expressed in this model closely resemble the progressive lower limb dysfunction of ALS patients. Among other imaging tools, MR diffusion tensor imaging （DTI） has emerged as a crucial, noninvasive and real time neuroimaging tool to gather information in ALS. One of the current concerns with the use of DTI is the lack of biological validation of the microstructural information given by this technique. Although clinical studies using DTI can provide a remarkable insight on the targets of neurodegeneration and disease course,they lack histological correlations. To address these shortcomings, preclinical models can be designed to validate the microstructural information unveiled by this particular MRI technique. Thus, the scope of this review is to describe how MRI diffusion and optical microscopy evaluate axonal structural changes at early stages of the disease in a preclinical model of ALS.展开更多
A novel gravity assist space pruning(GASP)algorithm based on image tools is proposed for solving interplanetary trajectory optimization problem.Compared with traditional GASP algorithm,the concept of image is introduc...A novel gravity assist space pruning(GASP)algorithm based on image tools is proposed for solving interplanetary trajectory optimization problem.Compared with traditional GASP algorithm,the concept of image is introduced to avoid missing interesting solutions with appropriate number of function evaluations.Image tools allow us to evaluate the objective function in regions in place of points and provide an effective way to evaluate the forward and backward constraints for the multi-gravity assist trajectory optimization problem.Since the interesting solutions of the interplanetary trajectory optimization problem are often clustered in a small portion of the search space rather than being overall evenly distributed,the regionwise evaluations with image tools make the little large interval with the proper Lipschitzian tolerances sampling effective.The detailed steps of the proposed method are presented and two examples including Earth Venus Mars(EVM)transfer and Earth Venus Venus Earth Jupiter Saturn(EVVEJS)transfer are given.Finally,a comparison with solutions given by the literature demonstrates the effectiveness of the proposed method.展开更多
Coronavirus disease 2019(COVID-19)is a global pandemic where several comorbidities have been shown to have a significant effect on mortality.Patients with diabetes mellitus(DM)have a higher mortality rate than non-DM ...Coronavirus disease 2019(COVID-19)is a global pandemic where several comorbidities have been shown to have a significant effect on mortality.Patients with diabetes mellitus(DM)have a higher mortality rate than non-DM patients if they get COVID-19.Recent studies have indicated that patients with a history of diabetes can increase the risk of severe acute respiratory syndrome coronavirus 2 infection.Additionally,patients without any history of diabetes can acquire newonset DM when infected with COVID-19.Thus,there is a need to explore the bidirectional link between these two conditions,confirming the vicious loop between“DM/COVID-19”.This narrative review presents(1)the bidirectional association between the DM and COVID-19,(2)the manifestations of the DM/COVID-19 loop leading to cardiovascular disease,(3)an understanding of primary and secondary factors that influence mortality due to the DM/COVID-19 loop,(4)the role of vitamin-D in DM patients during COVID-19,and finally,(5)the monitoring tools for tracking atherosclerosis burden in DM patients during COVID-19 and“COVID-triggered DM”patients.We conclude that the bidirectional nature of DM/COVID-19 causes acceleration towards cardiovascular events.Due to this alarming condition,early monitoring of atherosclerotic burden is required in“Diabetes patients during COVID-19”or“new-onset Diabetes triggered by COVID-19 in Non-Diabetes patients”.展开更多
Chemosensors and imaging probes have been the focus of significant research interest over the past few decades.In part due to ease of preparation and simplicity in manipulation,fluorescent probes have been extensively...Chemosensors and imaging probes have been the focus of significant research interest over the past few decades.In part due to ease of preparation and simplicity in manipulation,fluorescent probes have been extensively used for biomedical applications.When used for in vitro cell imaging[1,2]。展开更多
A simple approach to calculate the amplitude component of a wave front propagating in space from a hologram is proposed. It is able to calculate the amplitude distribution on a plane at any distance rapidly using a st...A simple approach to calculate the amplitude component of a wave front propagating in space from a hologram is proposed. It is able to calculate the amplitude distribution on a plane at any distance rapidly using a standard GPU. This is useful for analyzing and reconstructing the 3D image encoded on a hologram.展开更多
基金provided by the Chicago Biomedical Consortium’s Postdoctoral Research Award,No.085740
文摘The G93A-SOD1 mice model and MRI diffusion as a preclinical tool to study amyotrophic lateral sclerosis （ALS）： ALS is a progressive neurological disease characterized primarily by the development of limb paralysis, which eventually leads to lack of control on muscles under voluntary control and death within 3–5 years. Genetic heterogeneity and environmental factors play a critical role in the rate of disease progression and patients display faster declines once the symptoms have manifested. Since its original discovery, ALS has been associated with pathological alterations in motor neurons located in the spinal cord （SC）, where neuronal loss by a mutation in the protein superoxide dismutase in parenthesis （mSOD1） and impairment in axonal connectivity, have been linked to early functional impairments. In addition,mechanisms of neuroinflammation, apoptosis, necroptosis and autophagy have been also implicated in the development of this disease. Among different animal models developed to study ALS, the transgenic G93A-SOD1 mouse has become recognized as a benchmark model for preclinical screening of ALS therapies. Furthermore, the progressive alterations in the locomotor phenotype expressed in this model closely resemble the progressive lower limb dysfunction of ALS patients. Among other imaging tools, MR diffusion tensor imaging （DTI） has emerged as a crucial, noninvasive and real time neuroimaging tool to gather information in ALS. One of the current concerns with the use of DTI is the lack of biological validation of the microstructural information given by this technique. Although clinical studies using DTI can provide a remarkable insight on the targets of neurodegeneration and disease course,they lack histological correlations. To address these shortcomings, preclinical models can be designed to validate the microstructural information unveiled by this particular MRI technique. Thus, the scope of this review is to describe how MRI diffusion and optical microscopy evaluate axonal structural changes at early stages of the disease in a preclinical model of ALS.
基金supported by the National High Technology Research and Development Program (863)of China (2012AA121602)the National Natural Science Foundation of China(11078001)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China (20133218120037)the Fundamental Research Funds for the Central Universities under Grant(NS2014091)
文摘A novel gravity assist space pruning(GASP)algorithm based on image tools is proposed for solving interplanetary trajectory optimization problem.Compared with traditional GASP algorithm,the concept of image is introduced to avoid missing interesting solutions with appropriate number of function evaluations.Image tools allow us to evaluate the objective function in regions in place of points and provide an effective way to evaluate the forward and backward constraints for the multi-gravity assist trajectory optimization problem.Since the interesting solutions of the interplanetary trajectory optimization problem are often clustered in a small portion of the search space rather than being overall evenly distributed,the regionwise evaluations with image tools make the little large interval with the proper Lipschitzian tolerances sampling effective.The detailed steps of the proposed method are presented and two examples including Earth Venus Mars(EVM)transfer and Earth Venus Venus Earth Jupiter Saturn(EVVEJS)transfer are given.Finally,a comparison with solutions given by the literature demonstrates the effectiveness of the proposed method.
文摘Coronavirus disease 2019(COVID-19)is a global pandemic where several comorbidities have been shown to have a significant effect on mortality.Patients with diabetes mellitus(DM)have a higher mortality rate than non-DM patients if they get COVID-19.Recent studies have indicated that patients with a history of diabetes can increase the risk of severe acute respiratory syndrome coronavirus 2 infection.Additionally,patients without any history of diabetes can acquire newonset DM when infected with COVID-19.Thus,there is a need to explore the bidirectional link between these two conditions,confirming the vicious loop between“DM/COVID-19”.This narrative review presents(1)the bidirectional association between the DM and COVID-19,(2)the manifestations of the DM/COVID-19 loop leading to cardiovascular disease,(3)an understanding of primary and secondary factors that influence mortality due to the DM/COVID-19 loop,(4)the role of vitamin-D in DM patients during COVID-19,and finally,(5)the monitoring tools for tracking atherosclerosis burden in DM patients during COVID-19 and“COVID-triggered DM”patients.We conclude that the bidirectional nature of DM/COVID-19 causes acceleration towards cardiovascular events.Due to this alarming condition,early monitoring of atherosclerotic burden is required in“Diabetes patients during COVID-19”or“new-onset Diabetes triggered by COVID-19 in Non-Diabetes patients”.
文摘Chemosensors and imaging probes have been the focus of significant research interest over the past few decades.In part due to ease of preparation and simplicity in manipulation,fluorescent probes have been extensively used for biomedical applications.When used for in vitro cell imaging[1,2]。
基金the UK Engineering and Physical Sciences Research Council (EPSRC) for the support through the Platform Grant in Liquid Crystal Photonics
文摘A simple approach to calculate the amplitude component of a wave front propagating in space from a hologram is proposed. It is able to calculate the amplitude distribution on a plane at any distance rapidly using a standard GPU. This is useful for analyzing and reconstructing the 3D image encoded on a hologram.
