BACKGROUND:H uman pluripotent stem cell-derived cardiomyocytes offer an ideal cellular resource for studying heart diseases,conducting drug screening,developing in vitro heart models,and exploring potential cell therapies.However,human pluripotent stem cell-derived cardiomyocytes are characterized by immaturity with limited specific gene expression,low Ca2+processing levels,and underdeveloped structural,metabolic,and electrophysiological features.These limitations significantly impede the application of human pluripotent stem cell-derived cardiomyocytes.OBJECTIVE:To review the academic progress and clinical application of promoting the maturation of human pluripotent stem cell-derived cardiomyocytes by in vitro synthetic microenvironment.METHODS:CNKI,WanFang,VIP,PubMed,Web of Science,and Medline databases were searched,with"human pluripotent stem cells,human myocardial cells,hPSC-CMs,mature,OA,human pluripotent stem cell-derived cardiomyocytes,hPSC-CMs"as English search terms and"human pluripotent stem cells,cardiomyocytes,mature,OA,hPSC-CMs"as Chinese search terms.All relevant literature published from January 2002 to July 2024 was retrieved and 82 articles were included in the review.RESULTS AND CONCLUSION:(1)In recent years,in vitro synthetic microenvironments have attracted extensive attention due to their excellent intrinsic properties such as stiffness,plasticity,nanoscale morphology,and chemical functionality.(2)Human pluripotent stem cell-derived cardiomyocytes can be used as an effective platform for the treatment of cardiovascular diseases.(3)Mechanical stimulation,electrical stimulation,addition of biochemical molecules,and three-dimensional culture methods are effective methods to promote the maturation of human pluripotent stem cell-derived cardiomyocytes,which can further promote the clinical application of human pluripotent stem cell-derived cardiomyocytes.

Objective To develop a deep learning-based denoising model for accelerating Monte Carlo(MC)simulation of electronic portal imaging device(EPID)transit dose images.Methods A total of 500 EPID fields were collected from 100 lung cancer patients undergoing 5-field intensity-modulated radiotherapy,with 400 fields randomly selected as training set,50 fields as validation set,and 50 fields as test set.EPID transit dose image datasets with low particle counts(1×107)and high particle counts(1×109)were simulated using the GPU-accelerated MC dose calculation engine ARCHER.A denoising network model named SUNet was constructed based on Swin Transformer and U-Net,and trained using low-particle-count images as input and high-particle-count images as output.Following training,SUNet model was used to denoise low-particle-count EPID images in the test set.Denoising performance was evaluated using structural similarity index(SSIM),peak signal-to-noise ratio(PSNR),and Gamma passing rates(3%/2 mm),and the computational efficiency of MC simulation combined with SUNet model was analyzed.Results Compared with the original low-particle-count images,the SUNet-denoised images showed significantly improved quality,reduced noise points,and smoother dose distribution.When benchmarked against high-particle-count images,the SUNet-denoised images achieved an average SSIM greater than 0.9,an average PSNR higher than 32 dB,and an average gamma passing rate exceeding 90%.The MC simulation combined with SUNet model required only 1.88 s to simulate a single EPID transit dose image,representing an approximate 40-fold improvement in computational efficiency as compared with high-particle-count MC simulation.Conclusion The deep learning-based denoising model substantially accelerates MC simulation of EPID transit dose images while preserving both image quality and dose accuracy,which provides possibilities for EPID-basedin vivodose verification.

Hypertrophic cardiomyopathy (HCM) is a major contributor to cardiovascular diseases (CVD), the leading cause of death globally. HCM can precipitate heart failure (HF) by causing the cardiac tissue to weaken and stretch, thereby impairing its pumping efficiency. Moreover, HCM increases the risk of atrial fibrillation, which in turn elevates the likelihood of thrombus formation and stroke. Given these significant clinical ramifications, research into the etiology and pathogenesis of HCM is intensifying at multiple levels. In this review, we discuss and synthesize the latest findings on HCM pathogenesis, drawing on key experimental studies conducted both in vitro and in vivo. We also offer our insights and perspectives on these mechanisms, while highlighting the limitations of current research. Advancing fundamental research in this area is essential for developing effective therapeutic interventions and enhancing the clinical management of HCM.
Cardiomyopathy, Hypertrophic/physiopathology* ; Humans ; Animals

Objective To explore the role and mechanism of HJT-sRNA-m7(M7)bencaosome in a silicosis mouse model.Methods C57BL/6J mice were randomly divided into four groups:blank,control,negative control(NC)oligonucleotide,and M7 treatment(HJT-sRNA-m7 bencaosome)groups.After three rounds of pretreatment with HJT-sRNA-m7 bencaosome,all groups except the blank one were modeled via a single intratracheal exposure.Each mouse received 50 μL of a silica suspension at a dose of 200 mg/kg body weight via intratracheal instillation.From day 6 to day 26,the bencaosome was administered every other day via oral gavages.On day 28,pulmonary function tests were performed.Bronchoalveolar lavage fluid was collected for flow cytometry and cytokine analysis.The left lung was harvested for histopathological examination and Masson's trichrome staining to evaluate collagen fiber dep-osition.The right lung was used for hydroxyproline quantification to assess collagen accumulation.Results The re-sults of pulmonary function test,pathological analysis and hydroxyproline measurements all indicated that M7 ben-caosome treatment significantly alleviated silica-induced pulmonary fibrosis.Moreover,flow cytometry analysis of BALF confirmed that M7 bencaosome inhibited the silica-induced inflammatory response,that was supported by cy-tokine analysis.Conclusions HJT-sRNA-m7 bencaosome is quite effective to treat silicosis and inhibits mitigating pulmonary fibrosis progression in mouse models.

Objective:To analyze the influences of coronary angiography(CAG)of transradial artery on the success rate,radiation dose and safety in elderly patients with coronary heart disease(CHD).Methods:This study conducted a prospective study.A total of 150 elderly CHD patients who admitted to Heilongjiang Rad Cross Sengong General Hospital from November 2022 to November 2023 were selected,and they were randomly divided into three groups using a random number table,which included the femoral artery group(n=50),radial artery group(n=50),and ulnar artery group(n=50).The femoral artery group underwent CAG by using the femoral artery approach,and the radial artery group underwent CAG by using the radial artery approach,and the ulnar artery group underwent CAG by using the ulnar artery approach.The CAG success rate and CAG indicators[dosage of contrast agent,X-ray exposure time,time of conducting puncture,corrected TIMI frame count(CTFC)]were compared among the three groups.The radiation-related parameters[cumulative dose(CD),dose-area product(DAP)]also were compared among three groups.The patients'comfort degrees of three groups were assessed by adopting General Comfort Questionnaire(GCQ)at three time points(pre-CAG,during CAG,at the 12th hour post-CAG).In addition,the complications of three groups were recorded.Results:The numbers of success angiography were respectively 47 cases,48 cases and 46 cases in femoral artery group,radial artery group and ulnar artery group,and the success rates of them were respectively 94.00%(47/50),96.00%(48/50)and 92.00%(46/50),without statistically significant differences among three groups(P>0.05).There were not significant differences in the dosage of contrast agent,X-ray exposure time,time of conducting puncture,CTFC,CD and DAP among three groups(P>0.05).In the GCQ scores,the scores pre-CAG of all three groups were highest,followed by those at the 12th hour post-CAG,and then,those during CAG were lowest,which appeared a trend of rise after decline.The total incidence of complication was lowest(6.25%)in the radial artery group,followed by the ulnar artery group(10.87%),and that(21.28%)of the femoral artery group was the highest,but there was not statistically significant difference in that among three groups(P>0.05).Conclusion:The CAG success rates of the radial artery,femoral artery and ulnar artery are similar,and there is not significant difference in radiation dose.However,compared with CAG of femoral artery and ulnar artery,the CAG of radial artery has higher safety,and higher comfort degree at the same time.

As a new generation of time-of-flight mass spectrometry,multiple-reflection time-of-flight mass spectrometry(MR-TOF-MS)has been increasingly applied in the fields such as nuclear physics,chemistry,and biology due to its ultra-high resolution and rapid analysis capabilities.However,the analytical performance of MR-TOF-MS largely depends on the ion bunch state entering the mass analyzer.In this study,a rectangular ion trap(RIT)was developed,designed and processed using printed circuit board technology,as an ion accumulating and focusing device for MR-TOF mass analyzer.Compared to traditional ion traps composed of two sets of planar electrodes,this RIT had higher voltage utilization efficiency,resulting in more efficient ion collection and focusing.The ions were cooled to a sufficiently small bunch for precise mass measurement with MR-TOF-MS mass spectrometry in only 1 ms of cooling time in the RIT,then orthogonally ejected to the MR-TOF mass spectrometer for mass analysis.Experimental results indicated that the working cycle,ion flux,and ion focusing state of the RIT fully met the requirements of the MR-TOF mass analyzer.When coupled with the MR-TOF mass analyzer,the RIT enabled MR-TOF-MS to achieve a mass resolution of 1.5×105.

BACKGROUND:H uman pluripotent stem cell-derived cardiomyocytes offer an ideal cellular resource for studying heart diseases,conducting drug screening,developing in vitro heart models,and exploring potential cell therapies.However,human pluripotent stem cell-derived cardiomyocytes are characterized by immaturity with limited specific gene expression,low Ca2+processing levels,and underdeveloped structural,metabolic,and electrophysiological features.These limitations significantly impede the application of human pluripotent stem cell-derived cardiomyocytes.OBJECTIVE:To review the academic progress and clinical application of promoting the maturation of human pluripotent stem cell-derived cardiomyocytes by in vitro synthetic microenvironment.METHODS:CNKI,WanFang,VIP,PubMed,Web of Science,and Medline databases were searched,with"human pluripotent stem cells,human myocardial cells,hPSC-CMs,mature,OA,human pluripotent stem cell-derived cardiomyocytes,hPSC-CMs"as English search terms and"human pluripotent stem cells,cardiomyocytes,mature,OA,hPSC-CMs"as Chinese search terms.All relevant literature published from January 2002 to July 2024 was retrieved and 82 articles were included in the review.RESULTS AND CONCLUSION:(1)In recent years,in vitro synthetic microenvironments have attracted extensive attention due to their excellent intrinsic properties such as stiffness,plasticity,nanoscale morphology,and chemical functionality.(2)Human pluripotent stem cell-derived cardiomyocytes can be used as an effective platform for the treatment of cardiovascular diseases.(3)Mechanical stimulation,electrical stimulation,addition of biochemical molecules,and three-dimensional culture methods are effective methods to promote the maturation of human pluripotent stem cell-derived cardiomyocytes,which can further promote the clinical application of human pluripotent stem cell-derived cardiomyocytes.

Objective To develop a deep learning-based denoising model for accelerating Monte Carlo(MC)simulation of electronic portal imaging device(EPID)transit dose images.Methods A total of 500 EPID fields were collected from 100 lung cancer patients undergoing 5-field intensity-modulated radiotherapy,with 400 fields randomly selected as training set,50 fields as validation set,and 50 fields as test set.EPID transit dose image datasets with low particle counts(1×107)and high particle counts(1×109)were simulated using the GPU-accelerated MC dose calculation engine ARCHER.A denoising network model named SUNet was constructed based on Swin Transformer and U-Net,and trained using low-particle-count images as input and high-particle-count images as output.Following training,SUNet model was used to denoise low-particle-count EPID images in the test set.Denoising performance was evaluated using structural similarity index(SSIM),peak signal-to-noise ratio(PSNR),and Gamma passing rates(3%/2 mm),and the computational efficiency of MC simulation combined with SUNet model was analyzed.Results Compared with the original low-particle-count images,the SUNet-denoised images showed significantly improved quality,reduced noise points,and smoother dose distribution.When benchmarked against high-particle-count images,the SUNet-denoised images achieved an average SSIM greater than 0.9,an average PSNR higher than 32 dB,and an average gamma passing rate exceeding 90%.The MC simulation combined with SUNet model required only 1.88 s to simulate a single EPID transit dose image,representing an approximate 40-fold improvement in computational efficiency as compared with high-particle-count MC simulation.Conclusion The deep learning-based denoising model substantially accelerates MC simulation of EPID transit dose images while preserving both image quality and dose accuracy,which provides possibilities for EPID-basedin vivodose verification.

Objective:To analyze the influences of coronary angiography(CAG)of transradial artery on the success rate,radiation dose and safety in elderly patients with coronary heart disease(CHD).Methods:This study conducted a prospective study.A total of 150 elderly CHD patients who admitted to Heilongjiang Rad Cross Sengong General Hospital from November 2022 to November 2023 were selected,and they were randomly divided into three groups using a random number table,which included the femoral artery group(n=50),radial artery group(n=50),and ulnar artery group(n=50).The femoral artery group underwent CAG by using the femoral artery approach,and the radial artery group underwent CAG by using the radial artery approach,and the ulnar artery group underwent CAG by using the ulnar artery approach.The CAG success rate and CAG indicators[dosage of contrast agent,X-ray exposure time,time of conducting puncture,corrected TIMI frame count(CTFC)]were compared among the three groups.The radiation-related parameters[cumulative dose(CD),dose-area product(DAP)]also were compared among three groups.The patients'comfort degrees of three groups were assessed by adopting General Comfort Questionnaire(GCQ)at three time points(pre-CAG,during CAG,at the 12th hour post-CAG).In addition,the complications of three groups were recorded.Results:The numbers of success angiography were respectively 47 cases,48 cases and 46 cases in femoral artery group,radial artery group and ulnar artery group,and the success rates of them were respectively 94.00%(47/50),96.00%(48/50)and 92.00%(46/50),without statistically significant differences among three groups(P>0.05).There were not significant differences in the dosage of contrast agent,X-ray exposure time,time of conducting puncture,CTFC,CD and DAP among three groups(P>0.05).In the GCQ scores,the scores pre-CAG of all three groups were highest,followed by those at the 12th hour post-CAG,and then,those during CAG were lowest,which appeared a trend of rise after decline.The total incidence of complication was lowest(6.25%)in the radial artery group,followed by the ulnar artery group(10.87%),and that(21.28%)of the femoral artery group was the highest,but there was not statistically significant difference in that among three groups(P>0.05).Conclusion:The CAG success rates of the radial artery,femoral artery and ulnar artery are similar,and there is not significant difference in radiation dose.However,compared with CAG of femoral artery and ulnar artery,the CAG of radial artery has higher safety,and higher comfort degree at the same time.

Hydrogel is a kind of material with high water content,good biocompatibility and extracellular matrix-like property,among which polypyrrole(PPy)conductive hydrogels have both physical characteristics and excellent conductivity of hydrogels themselves.Its conductivity can be used to detect electrical signals generated in biological systems and provide electrical stimulation to regulate the activities and functions of cells and tissues.These characteristics make it widely used in the biomedical field.The recent progress of PPy conductive hydrogels in biomedical field was reviewed in this paper.In terms of classification,according to the cross-linking mechanism of PPy and hydrogel matrix,the non-covalent cross-linked PPy conductive hydrogels and covalent cross-linked PPy conductive hydrogels were divided.The applications of PPy conductive hydrogels in the biomedical field(Skin damage repair,nerve repair,myocardial repair and flexible sensing,etc.)were mainly introduced,and the development trend and challenges of PPy conductive hydrogels in the biomedical field were discussed.