Reduced nicotinamide adenine dinucleotide(NADH)plays a crucial role in many biochemical reactions in human metabolism.In this work,a flow-mediated skin fluorescence(FMSF)-postocclusion reactive hyperaemia(PORH)system ...Reduced nicotinamide adenine dinucleotide(NADH)plays a crucial role in many biochemical reactions in human metabolism.In this work,a flow-mediated skin fluorescence(FMSF)-postocclusion reactive hyperaemia(PORH)system was developed for noninvasive and in vivo measurement of NADH fluorescence and its real-time dynamical changes in human skin tissue.The real-time dynamical changes of NADH fluorescence were analyzed with the changes of skin blood flow measured by laser speckle contrast imaging(LSCI)experiments simultaneously with FMSFPORH measurements,which suggests that the dynamical changes of NADH fluorescence would be mainly correlated with the intrinsic changes of NADH level in the skin tissue.In addition,Monte Carlo simulations were applied to understand the impact of optical property changes on the dynamical changes of NADH fluorescence during the PORH process,which further supports that the dynamical changes of NADH fluorescence measured in our system would be intrinsic changes of NADH level in the skin tissue.展开更多
Blood flow is essential for maintaining normal physiological functions of the human body.Endoscopic laser speckle contrast imaging(LSCI)can achieve rapid,high-resolution,label-free,and long-term blood flow perfusion v...Blood flow is essential for maintaining normal physiological functions of the human body.Endoscopic laser speckle contrast imaging(LSCI)can achieve rapid,high-resolution,label-free,and long-term blood flow perfusion velocity monitoring in minimally invasive surgery.However,conventional endoscopic LSCI uses a lowcoherence laser illumination scheme,leading to restricted angles of illumination,compromised laser coherence,uneven laser illumination distribution,and low coupling efficiency,all of which degrade the quality of LSCI in the endoscope.In this paper,we propose that conical fiber(CF)-coupled high-coherence laser can be used to achieve large-angle,high-coherence,high-uniformity,and high coupling efficiency laser illumination in the endoscope.Additionally,we establish an effective model for calculating the divergence angle of CFs.Through phantom and animal experiments,we reveal that laser illumination based on CF markedly enhances endoscopic LSCI performance.This technology broadens the imaging field of view,enhances the signal-to-noise ratio,enables more sensitive detection of minute blood flow changes,expands the detectable flow range,and improves signal-to-background ratio of endoscopic LSCI.Our findings suggest that CF-based laser illumination stands as a highly promising advancement in endoscopic LSCI.展开更多
Laser speckle contrast imaging （LSCI） is a powerful tool for blood flow mapping. In this paper, we described a simple algorithm based on histogram analysis of laser speckle contrast image to provide rapid differenti...Laser speckle contrast imaging （LSCI） is a powerful tool for blood flow mapping. In this paper, we described a simple algorithm based on histogram analysis of laser speckle contrast image to provide rapid differentiation between macro- and microcirculations. The algorithm was successfully verified by the study of blood flow in rat cortex under functional activation.展开更多
Stroke is a major health concern and an intensive research subject due that it is the major cause of death and the leading cause of disability worldwide. The past three decades of clinical disappointments in treating ...Stroke is a major health concern and an intensive research subject due that it is the major cause of death and the leading cause of disability worldwide. The past three decades of clinical disappointments in treating stroke must compel us to rethink our strategy. New effective protocol for stroke could greatly benefit from the advances in optical imaging technologies. This review focuses on the latest advance of applications of three optical imaging techniques in animal model of stroke, such as photoacoustic （PA） imaging, laser speckle contrast imaging （LSCI） and two-photon microscopy （TPM）. The potential roles of those techniques in the future of stroke management are also discussed.展开更多
The interaction between humans and their environment significantly impacts the health of urban residents.However,there is limited research on assessing the spatiotemporal variations of human thermal exposure as well a...The interaction between humans and their environment significantly impacts the health of urban residents.However,there is limited research on assessing the spatiotemporal variations of human thermal exposure as well as inequalities and their relationships with greenspace based on remote sensing data,especially in developing countries.This study offers a framework utilizing pixel-wise data on land surface coolness index(LSCI),normalized difference vegetation index(NDVI),and population metrics to evaluate population-weighted thermal and greenspace exposures in China’s Greater Bay Area(GBA)over eleven years(2010–2020).It further examines thermal exposure inequality using the Gini index and explores both natural and socio-economical drivers of thermal exposure and its inequality.The results indicate an increasing trend of cities within the GBA being experiencing detrimental thermal conditions.Over the study period,the proportion of cities with high exposure to LSCI and NDVI exhibited a general decline.Approximately 63.6%of major cities observed growing imbalances in LSCI and NDVI exposures over eleven years.Notably,there were positive correlations between NDVI exposure and LSCI exposure,along with their associated inequalities.Moreover,coastal cities characterized by lower elevations,higher precipitation rates,and rapid economic growth experienced higher levels of LSCI and NDVI exposures yet these cities also demonstrated greater disparities.展开更多
基金supported by the Natural Science Foundation of Hubei Province(Grant No.2020CFB380)the Educational Commission of Hubei Province of China(Grant No.Q20191506).
文摘Reduced nicotinamide adenine dinucleotide(NADH)plays a crucial role in many biochemical reactions in human metabolism.In this work,a flow-mediated skin fluorescence(FMSF)-postocclusion reactive hyperaemia(PORH)system was developed for noninvasive and in vivo measurement of NADH fluorescence and its real-time dynamical changes in human skin tissue.The real-time dynamical changes of NADH fluorescence were analyzed with the changes of skin blood flow measured by laser speckle contrast imaging(LSCI)experiments simultaneously with FMSFPORH measurements,which suggests that the dynamical changes of NADH fluorescence would be mainly correlated with the intrinsic changes of NADH level in the skin tissue.In addition,Monte Carlo simulations were applied to understand the impact of optical property changes on the dynamical changes of NADH fluorescence during the PORH process,which further supports that the dynamical changes of NADH fluorescence measured in our system would be intrinsic changes of NADH level in the skin tissue.
基金National Key Research and Development Program of China(2021YFC2400102)National Natural Science Foundation of China(62275095,82261138559,62305125,61890951,61890950)+2 种基金Hainan University Research Startup Fund(KYQD(ZR)20072,KYQD(ZR)22074)Chinese Academy of Medical Sciences Initiative for Innovative Medicine(2019-I2M-5-014)Innovation Fund of WNLO。
文摘Blood flow is essential for maintaining normal physiological functions of the human body.Endoscopic laser speckle contrast imaging(LSCI)can achieve rapid,high-resolution,label-free,and long-term blood flow perfusion velocity monitoring in minimally invasive surgery.However,conventional endoscopic LSCI uses a lowcoherence laser illumination scheme,leading to restricted angles of illumination,compromised laser coherence,uneven laser illumination distribution,and low coupling efficiency,all of which degrade the quality of LSCI in the endoscope.In this paper,we propose that conical fiber(CF)-coupled high-coherence laser can be used to achieve large-angle,high-coherence,high-uniformity,and high coupling efficiency laser illumination in the endoscope.Additionally,we establish an effective model for calculating the divergence angle of CFs.Through phantom and animal experiments,we reveal that laser illumination based on CF markedly enhances endoscopic LSCI performance.This technology broadens the imaging field of view,enhances the signal-to-noise ratio,enables more sensitive detection of minute blood flow changes,expands the detectable flow range,and improves signal-to-background ratio of endoscopic LSCI.Our findings suggest that CF-based laser illumination stands as a highly promising advancement in endoscopic LSCI.
文摘Laser speckle contrast imaging （LSCI） is a powerful tool for blood flow mapping. In this paper, we described a simple algorithm based on histogram analysis of laser speckle contrast image to provide rapid differentiation between macro- and microcirculations. The algorithm was successfully verified by the study of blood flow in rat cortex under functional activation.
文摘Stroke is a major health concern and an intensive research subject due that it is the major cause of death and the leading cause of disability worldwide. The past three decades of clinical disappointments in treating stroke must compel us to rethink our strategy. New effective protocol for stroke could greatly benefit from the advances in optical imaging technologies. This review focuses on the latest advance of applications of three optical imaging techniques in animal model of stroke, such as photoacoustic （PA） imaging, laser speckle contrast imaging （LSCI） and two-photon microscopy （TPM）. The potential roles of those techniques in the future of stroke management are also discussed.
基金supported by the National Natural Science Foundation of China(No.52278108)Guangdong Natural Science Foundation(No.2024A1515011415,No.2023A1515012188)State Key Laboratory of Subtropical Building and Urban Science(No.2023ZB05,No.2023ZB04)。
文摘The interaction between humans and their environment significantly impacts the health of urban residents.However,there is limited research on assessing the spatiotemporal variations of human thermal exposure as well as inequalities and their relationships with greenspace based on remote sensing data,especially in developing countries.This study offers a framework utilizing pixel-wise data on land surface coolness index(LSCI),normalized difference vegetation index(NDVI),and population metrics to evaluate population-weighted thermal and greenspace exposures in China’s Greater Bay Area(GBA)over eleven years(2010–2020).It further examines thermal exposure inequality using the Gini index and explores both natural and socio-economical drivers of thermal exposure and its inequality.The results indicate an increasing trend of cities within the GBA being experiencing detrimental thermal conditions.Over the study period,the proportion of cities with high exposure to LSCI and NDVI exhibited a general decline.Approximately 63.6%of major cities observed growing imbalances in LSCI and NDVI exposures over eleven years.Notably,there were positive correlations between NDVI exposure and LSCI exposure,along with their associated inequalities.Moreover,coastal cities characterized by lower elevations,higher precipitation rates,and rapid economic growth experienced higher levels of LSCI and NDVI exposures yet these cities also demonstrated greater disparities.
