Background:It is challenging to repair wide or irregular defects with traditional skin flaps,and anterolateral thigh(ALT)lobulated perforator flaps are an ideal choice for such defects.However,there are many variation...Background:It is challenging to repair wide or irregular defects with traditional skin flaps,and anterolateral thigh(ALT)lobulated perforator flaps are an ideal choice for such defects.However,there are many variations in perforators,so good preoperative planning is very important.This study attempted to explore the feasibility and clinical effect of digital technology in the use of ALT lobulated perforator flaps for repairing complex soft tissue defects in limbs.Methods:Computed tomography angiography(CTA)was performed on 28 patients with complex soft tissue defects of the limbs,and the CTA data were imported into Mimics 20.0 software in DICOM format.According to the perforation condition of the lateral circumflex femoral artery and the size of the limb defect,one thigh that had two or more perforators from the same source vessel was selected for 3D reconstruction of the ALT lobulated perforator flap model.Mimics 20.0 software was used to visualize the vascular anatomy,virtual design and harvest of the flap before surgery.The intraoperative design and excision of the ALT lobulated perforator flap were guided by the preoperative digital design,and the actual anatomical observations and measurements were recorded.Results:Digital reconstruction was successfully performed in all patients before surgery;this reconstruction dynamically displayed the anatomical structure of the flap vasculature and accurately guided the design and harvest of the flap during surgery.The parameters of the harvested flaps were consistent with the preoperative parameters.Postoperative complications occurred in 7 patients,but all flaps survived uneventfully.All of the donor sites were closed directly.All patients were followed up for 13-27 months(mean,19.75 months).The color and texture of each flap were satisfactory and each donor site exhibited a linear scar.Conclusions:Digital technology can effectively and precisely assist in the design and harvest of ALT lobulated perforator flaps,provide an effective approach for individualized evaluation and flap design and reduce the risk and difficulty of surgery.展开更多
AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reade...AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance. METHODS： The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size （≤3 cm or 〉≥3 cm） and scanning protocols （dedicated vs routine）. RESULTS： 28/164 cysts （mean size, 39 mm; range, 8-92 mm） were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance （22/28, 78.6%）, surface Iobulations （25/28, 89.3%） and central scar （9/28, 32.4%）. Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA （P = 0.0001）. The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and Iobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions 〉 3 cm （P = 0.02） and for MDCT scans performed using thin collimation （1.25-2.5 mm） compared to routine 5 mm collimation exams （P 〉 0.05）. CONCLUSION： Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface Iobulations offers accuracy comparable to central scar with higher sensitivity.展开更多
Mirror neuron system can be activated by observation and execution of an action.It has an important function of action understanding.We investigated brain activations in humans by observing the strength of a hand gras...Mirror neuron system can be activated by observation and execution of an action.It has an important function of action understanding.We investigated brain activations in humans by observing the strength of a hand grasp using functional magnetic resonance imaging.Twenty right-handed healthy individuals,consisting of 10 males and 10 females,aged 22.40 ± 2.04 years,were recruited into this study from September to November 2017 via posters.Light hand grasp task video showed a hand lightly grasping and releasing a ball repeatedly.Powerful hand grasp task video showed a hand tightly grasping and releasing a ball repeatedly.Functional magnetic resonance imaging block design paradigm comprised five stimulation blocks alternating with five baseline blocks.Stimulation blocks were presented with two stimulus tasks,consisting of a light grasp and a powerful grasp.Region of interest was defined around the inferior parietal lobule,inferior frontal gyrus,and superior temporal sulcus which have been called mirror neuron system.The inferior parietal lobule,fusiform,postcentral,occipital,temporal,and frontal gyri were activated during light and powerful grasp tasks.The BOLD signal response of a powerful grasp was stronger than that of a light grasp.These results suggest that brain activation of the inferior parietal lobule,which is the core brain region of the mirror neuron system,was stronger in the powerful grasp task than in the light grasp task.We believe that our results might be helpful for instructing rehabilitation of brain injury.This study was approved by the Institutional Review Board of Daegu Oriental Hospital of Daegu Haany University on September 8,2017 (approval No.DHUMC-D-17020-PRO-01).展开更多
AIM To clarify the histological changes associated with liver atrophy after percutaneous transhepatic portalembolization(PTPE) in pigs and humans. METHODS As a preliminary study, we performed pathological examinations...AIM To clarify the histological changes associated with liver atrophy after percutaneous transhepatic portalembolization(PTPE) in pigs and humans. METHODS As a preliminary study, we performed pathological examinations of liver specimens from five pigs that had undergone PTPE in a time-dependent model of liver atrophy. In specimens from embolized lobes(EMB) and nonembolized lobes(controls), we measured the portal vein to central vein distance(PV-CV), the area and number of hepatocytes per lobule, and apoptotic activity using the terminal deoxynucleotidyl transferase dU TP nickend labeling assay. Immunohistochemical reactivities were evaluated for light chain 3(LC3) and lysosomal-associated membrane protein 2(LAMP2) as autophagy markers and for glutamine synthetase and cytochrome P450 2 E1(CYP2 E1) as metabolic zonation markers. Samples from ten human livers taken 20-36 d after PTPE were similarly examined. RESULTS PV-CVs and lobule areas did not differ between EMB and controls at day 0, but were lower in EMB than in controls at weeks 2, 4, and 6(P ≤ 0.001). Hepatocyte numbers were not significantly reduced in EMB at day 0 and week 2 but were reduced at weeks 4 and 6(P ≤ 0.05). Apoptotic activity was higher in EMB than in controls at day 0 and week 4. LC3 and LAMP2 staining peaked in EMB at week 2, with no significant difference between EMB and controls at weeks 4 and 6. Glutamine synthetase and CYP2 E1 zonation in EMB at weeks 2, 4, and 6 were narrower than those in controls. Human results were consistent with those of porcine specimens. CONCLUSION The mechanism of liver atrophy after PTPE has two histological phases: Hepatocellular atrophy is likely caused by autophagy in the first 2 wk and apoptosis thereafter.展开更多
Classic respiratory mechanics is a branch of vectorial mechanics, which aims to recognize all forces acting on the respiratory system. Another branch of mechanics, analytical mechanics, has been used for analyzing the...Classic respiratory mechanics is a branch of vectorial mechanics, which aims to recognize all forces acting on the respiratory system. Another branch of mechanics, analytical mechanics, has been used for analyzing the motions of complicated systems with constraints through equilibrium among scalar quantities such as kinetic energy and potential energy. However, until now, there have not been any studies concerning about analytical respiratory mechanics. In this paper, the author has obtained two types of motion equations (linear and nonlinear) for the airflow limitation from formulation of the analytical respiratory mechanics. Reconstructed flow-volume trajectories of the linear equation revealed a new relationship among the slope of the linear portion of trajectory, the coefficient of the dissipation function and the coefficient of the potential function. Reconstructed trajectories of the nonlinear equation suggested that a curved flow-volume trajectory would be caused by the emergence of regional hypoventilated clusters with airtrapped lobules. In conclusion, analytical respiratory mechanics will provide the basis for analyzing the mechanical properties of the respiratory system con cerning pulmonary functional images made by newly developed technologies.展开更多
Many problems regarding structure-function relationships have remained unsolved in the field of respiratory physiology. In the present review, we highlighted these uncertain issues from a variety of anatomical and phy...Many problems regarding structure-function relationships have remained unsolved in the field of respiratory physiology. In the present review, we highlighted these uncertain issues from a variety of anatomical and physiological viewpoints. Model A of Weibel in which dichotomously branching airways are incorporated should be used for analyzing gas mixing in conducting and acinar airways. Acinus of Loeschcke is taken as an anatomical gas-exchange unit.Although it is difficult to define functional gas-exchange unit in a way entirely consistent with anatomical structures, acinus of Aschoff may serve as a functional gas-exchange unit in a first approximation. Based on anatomical and physiological perspectives, the multiple inert-gas elimination technique is thought to be highly effective for predicting ventilation-perfusion heterogeneity between acini of Aschoff under steady-state condition. Changes in effective alveolar P_(O2), the most important parameter in classical gas-exchange theory, are coherent with those in mixed alveolar P_(O2) decided from the multiple inert-gas elimination technique. Therefore, effective alveolar-arterial P_(O2) difference is considered useful for assessing gas-exchange abnormalities in lung periphery.However, one should be aware that although alveolar-arterial P_(O2) difference sensitively detects moderately low ventilation-perfusion regions causing hypoxemia, it is insensitive to abnormal gas exchange evoked by very low and high ventilation-perfusion regions. Pulmonary diffusing capacity for CO (D_(LCO))and the value corrected for alveolar volume (V_(AV)), i.e., D_(LCO)/V_(AV) (K_(CO)), are thought to be crucial for diagnosing alveolar-wall damages. D_(LCO)-related parameters have higher sensitivity to detecting abnormalities in pulmonary microcirculation than those in the alveolocapillary membrane. We would like to recommend four categories derived from combining behaviors of D_(LCO) with those of K_(CO) for differential diagnosis on anatomically morbid states in alveolar walls:type-1abnormality defined by decrease in both D_(LCO) and K_(CO); type-2 abnormality by decrease in D_(LCO) but increase in K_(CO); type-3 abnormality by decrease in D_(LCO) but restricted rise in K_(CO); and type-4 abnormality by increase in both D_(LCO) and K_(CO).展开更多
Epidermoid cysts are benign, developmental, superficial cysts found commonly on the face, trunk and neck. Its presence on the ear lobe is very rare. We shall describe the occurrence of an epidermoid cyst on the auricl...Epidermoid cysts are benign, developmental, superficial cysts found commonly on the face, trunk and neck. Its presence on the ear lobe is very rare. We shall describe the occurrence of an epidermoid cyst on the auricle along with the presence of a dermoid cyst over the occipital scalp and elaborate on the patient presentation, diagnosis, management along with the post-operative follow up.展开更多
Liver-tissue engineering has proven valuable in treating liver diseases,but the construction of liver tissues with high fidelity remains challenging.Here,we present a novel three-dimensional(3D)-imprinted cell-sheet s...Liver-tissue engineering has proven valuable in treating liver diseases,but the construction of liver tissues with high fidelity remains challenging.Here,we present a novel three-dimensional(3D)-imprinted cell-sheet strategy for the synchronous construction of biomimetic hepatic microtissues with high accuracy in terms of cell type,density,and distribution.To achieve this,the specific composition of hepatic cells in a normal human liver was determined using a spatial proteogenomics dataset.The data and biomimetic hepatic micro-tissues with hexagonal hollow cross-sections indicate that cell information was successfully generated using a homemade 3D-imprinted device for layer-by-layer imprinting and assembling the hepatic cell sheets.By infiltrating vascular endothelial cells into the hollow section of the assembly,biomimetic hepatic microtissues with vascularized channels for nutrient diffusion and drug perfusion can be obtained.We demonstrate that the resultant vascularized biomimetic hepatic micro-tissues can not only be integrated into a microfluidic drug-screening liver-on-a-chip but also assembled into an enlarged physiological structure to promote liver regeneration.We believe that our 3D-imprinted cell sheets strategy will open new avenues for biomimetic microtissue construction.展开更多
Three-dimensional(3D)bioprinting,an effective technique for building cell-laden structures providing native extracellular matrix environments,presents challenges,including inadequate cellular interactions.To address t...Three-dimensional(3D)bioprinting,an effective technique for building cell-laden structures providing native extracellular matrix environments,presents challenges,including inadequate cellular interactions.To address these issues,cell spheroids offer a promising solution for improving their biological functions.Particularly,minispheroids with 50-100μm diameters exhibit enhanced cellular maturation.We propose a one-step minispheroid-forming bioprinting process incorporating electrical stimulation(E-MS-printing).By stimulating the cells,minispheroids with controlled diameters were generated by manipulating the bioink viscosity and stimulation intensity.To validate its feasibility,E-MS-printing process was applied to fabricate an engineered liver model designed to mimic the hepatic lobule unit.E-MS-printing was employed to print the hepatocyte region,followed by bioprinting the central vein using a core-shell nozzle.The resulting constructs displayed native liver-mimetic structures containing minispheroids,which facilitated improved hepatic cell maturation,functional attributes,and vessel formation.Our results demonstrate a new potential 3D liver model that can replicate native liver tissues.展开更多
文摘Background:It is challenging to repair wide or irregular defects with traditional skin flaps,and anterolateral thigh(ALT)lobulated perforator flaps are an ideal choice for such defects.However,there are many variations in perforators,so good preoperative planning is very important.This study attempted to explore the feasibility and clinical effect of digital technology in the use of ALT lobulated perforator flaps for repairing complex soft tissue defects in limbs.Methods:Computed tomography angiography(CTA)was performed on 28 patients with complex soft tissue defects of the limbs,and the CTA data were imported into Mimics 20.0 software in DICOM format.According to the perforation condition of the lateral circumflex femoral artery and the size of the limb defect,one thigh that had two or more perforators from the same source vessel was selected for 3D reconstruction of the ALT lobulated perforator flap model.Mimics 20.0 software was used to visualize the vascular anatomy,virtual design and harvest of the flap before surgery.The intraoperative design and excision of the ALT lobulated perforator flap were guided by the preoperative digital design,and the actual anatomical observations and measurements were recorded.Results:Digital reconstruction was successfully performed in all patients before surgery;this reconstruction dynamically displayed the anatomical structure of the flap vasculature and accurately guided the design and harvest of the flap during surgery.The parameters of the harvested flaps were consistent with the preoperative parameters.Postoperative complications occurred in 7 patients,but all flaps survived uneventfully.All of the donor sites were closed directly.All patients were followed up for 13-27 months(mean,19.75 months).The color and texture of each flap were satisfactory and each donor site exhibited a linear scar.Conclusions:Digital technology can effectively and precisely assist in the design and harvest of ALT lobulated perforator flaps,provide an effective approach for individualized evaluation and flap design and reduce the risk and difficulty of surgery.
文摘AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance. METHODS： The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size （≤3 cm or 〉≥3 cm） and scanning protocols （dedicated vs routine）. RESULTS： 28/164 cysts （mean size, 39 mm; range, 8-92 mm） were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance （22/28, 78.6%）, surface Iobulations （25/28, 89.3%） and central scar （9/28, 32.4%）. Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA （P = 0.0001）. The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and Iobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions 〉 3 cm （P = 0.02） and for MDCT scans performed using thin collimation （1.25-2.5 mm） compared to routine 5 mm collimation exams （P 〉 0.05）. CONCLUSION： Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface Iobulations offers accuracy comparable to central scar with higher sensitivity.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(No.2017R1D1A1B03033985to MYL)+1 种基金the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(No.2018R1A5A2025272to MYL)
文摘Mirror neuron system can be activated by observation and execution of an action.It has an important function of action understanding.We investigated brain activations in humans by observing the strength of a hand grasp using functional magnetic resonance imaging.Twenty right-handed healthy individuals,consisting of 10 males and 10 females,aged 22.40 ± 2.04 years,were recruited into this study from September to November 2017 via posters.Light hand grasp task video showed a hand lightly grasping and releasing a ball repeatedly.Powerful hand grasp task video showed a hand tightly grasping and releasing a ball repeatedly.Functional magnetic resonance imaging block design paradigm comprised five stimulation blocks alternating with five baseline blocks.Stimulation blocks were presented with two stimulus tasks,consisting of a light grasp and a powerful grasp.Region of interest was defined around the inferior parietal lobule,inferior frontal gyrus,and superior temporal sulcus which have been called mirror neuron system.The inferior parietal lobule,fusiform,postcentral,occipital,temporal,and frontal gyri were activated during light and powerful grasp tasks.The BOLD signal response of a powerful grasp was stronger than that of a light grasp.These results suggest that brain activation of the inferior parietal lobule,which is the core brain region of the mirror neuron system,was stronger in the powerful grasp task than in the light grasp task.We believe that our results might be helpful for instructing rehabilitation of brain injury.This study was approved by the Institutional Review Board of Daegu Oriental Hospital of Daegu Haany University on September 8,2017 (approval No.DHUMC-D-17020-PRO-01).
基金Supported by National Cancer Center Research and Development Fund(23-A-35)
文摘AIM To clarify the histological changes associated with liver atrophy after percutaneous transhepatic portalembolization(PTPE) in pigs and humans. METHODS As a preliminary study, we performed pathological examinations of liver specimens from five pigs that had undergone PTPE in a time-dependent model of liver atrophy. In specimens from embolized lobes(EMB) and nonembolized lobes(controls), we measured the portal vein to central vein distance(PV-CV), the area and number of hepatocytes per lobule, and apoptotic activity using the terminal deoxynucleotidyl transferase dU TP nickend labeling assay. Immunohistochemical reactivities were evaluated for light chain 3(LC3) and lysosomal-associated membrane protein 2(LAMP2) as autophagy markers and for glutamine synthetase and cytochrome P450 2 E1(CYP2 E1) as metabolic zonation markers. Samples from ten human livers taken 20-36 d after PTPE were similarly examined. RESULTS PV-CVs and lobule areas did not differ between EMB and controls at day 0, but were lower in EMB than in controls at weeks 2, 4, and 6(P ≤ 0.001). Hepatocyte numbers were not significantly reduced in EMB at day 0 and week 2 but were reduced at weeks 4 and 6(P ≤ 0.05). Apoptotic activity was higher in EMB than in controls at day 0 and week 4. LC3 and LAMP2 staining peaked in EMB at week 2, with no significant difference between EMB and controls at weeks 4 and 6. Glutamine synthetase and CYP2 E1 zonation in EMB at weeks 2, 4, and 6 were narrower than those in controls. Human results were consistent with those of porcine specimens. CONCLUSION The mechanism of liver atrophy after PTPE has two histological phases: Hepatocellular atrophy is likely caused by autophagy in the first 2 wk and apoptosis thereafter.
文摘Classic respiratory mechanics is a branch of vectorial mechanics, which aims to recognize all forces acting on the respiratory system. Another branch of mechanics, analytical mechanics, has been used for analyzing the motions of complicated systems with constraints through equilibrium among scalar quantities such as kinetic energy and potential energy. However, until now, there have not been any studies concerning about analytical respiratory mechanics. In this paper, the author has obtained two types of motion equations (linear and nonlinear) for the airflow limitation from formulation of the analytical respiratory mechanics. Reconstructed flow-volume trajectories of the linear equation revealed a new relationship among the slope of the linear portion of trajectory, the coefficient of the dissipation function and the coefficient of the potential function. Reconstructed trajectories of the nonlinear equation suggested that a curved flow-volume trajectory would be caused by the emergence of regional hypoventilated clusters with airtrapped lobules. In conclusion, analytical respiratory mechanics will provide the basis for analyzing the mechanical properties of the respiratory system con cerning pulmonary functional images made by newly developed technologies.
文摘Many problems regarding structure-function relationships have remained unsolved in the field of respiratory physiology. In the present review, we highlighted these uncertain issues from a variety of anatomical and physiological viewpoints. Model A of Weibel in which dichotomously branching airways are incorporated should be used for analyzing gas mixing in conducting and acinar airways. Acinus of Loeschcke is taken as an anatomical gas-exchange unit.Although it is difficult to define functional gas-exchange unit in a way entirely consistent with anatomical structures, acinus of Aschoff may serve as a functional gas-exchange unit in a first approximation. Based on anatomical and physiological perspectives, the multiple inert-gas elimination technique is thought to be highly effective for predicting ventilation-perfusion heterogeneity between acini of Aschoff under steady-state condition. Changes in effective alveolar P_(O2), the most important parameter in classical gas-exchange theory, are coherent with those in mixed alveolar P_(O2) decided from the multiple inert-gas elimination technique. Therefore, effective alveolar-arterial P_(O2) difference is considered useful for assessing gas-exchange abnormalities in lung periphery.However, one should be aware that although alveolar-arterial P_(O2) difference sensitively detects moderately low ventilation-perfusion regions causing hypoxemia, it is insensitive to abnormal gas exchange evoked by very low and high ventilation-perfusion regions. Pulmonary diffusing capacity for CO (D_(LCO))and the value corrected for alveolar volume (V_(AV)), i.e., D_(LCO)/V_(AV) (K_(CO)), are thought to be crucial for diagnosing alveolar-wall damages. D_(LCO)-related parameters have higher sensitivity to detecting abnormalities in pulmonary microcirculation than those in the alveolocapillary membrane. We would like to recommend four categories derived from combining behaviors of D_(LCO) with those of K_(CO) for differential diagnosis on anatomically morbid states in alveolar walls:type-1abnormality defined by decrease in both D_(LCO) and K_(CO); type-2 abnormality by decrease in D_(LCO) but increase in K_(CO); type-3 abnormality by decrease in D_(LCO) but restricted rise in K_(CO); and type-4 abnormality by increase in both D_(LCO) and K_(CO).
文摘Epidermoid cysts are benign, developmental, superficial cysts found commonly on the face, trunk and neck. Its presence on the ear lobe is very rare. We shall describe the occurrence of an epidermoid cyst on the auricle along with the presence of a dermoid cyst over the occipital scalp and elaborate on the patient presentation, diagnosis, management along with the post-operative follow up.
基金supported by the National Natural Science Foundation of China(T2225003,and 82100664)the National Key Research and Development Program of China(2022YFA1105300)+4 种基金the Jiangsu Provincial Science and Technology Special Fund for Outstanding Young Scholars(BK20230051)the Nanjing Health Science and Technology Development Project for Distinguished Young Scholars(JQX22003)the Nanjing Medical Science and Technique Development Foundation(ZKX21019)the Clinical Trials from Nanjing Drum Tower Hospital(2022-LCYJ-ZD-01,and 2021-LCYJ-PY-46)the Guangdong Basic and Applied Basic Research Foundation(2021B1515120054).
文摘Liver-tissue engineering has proven valuable in treating liver diseases,but the construction of liver tissues with high fidelity remains challenging.Here,we present a novel three-dimensional(3D)-imprinted cell-sheet strategy for the synchronous construction of biomimetic hepatic microtissues with high accuracy in terms of cell type,density,and distribution.To achieve this,the specific composition of hepatic cells in a normal human liver was determined using a spatial proteogenomics dataset.The data and biomimetic hepatic micro-tissues with hexagonal hollow cross-sections indicate that cell information was successfully generated using a homemade 3D-imprinted device for layer-by-layer imprinting and assembling the hepatic cell sheets.By infiltrating vascular endothelial cells into the hollow section of the assembly,biomimetic hepatic microtissues with vascularized channels for nutrient diffusion and drug perfusion can be obtained.We demonstrate that the resultant vascularized biomimetic hepatic micro-tissues can not only be integrated into a microfluidic drug-screening liver-on-a-chip but also assembled into an enlarged physiological structure to promote liver regeneration.We believe that our 3D-imprinted cell sheets strategy will open new avenues for biomimetic microtissue construction.
基金supported by a grant from the Ministry of Trade,Industry&Energy(MOTIE,Korea)under Industrial Technology Innovation Program(20009652:Technology on commercialization and materials of Bioabsorbable Hydroxyapatite less than 1μm in size)supported by the“Korea National Institute of Health”research project(2022ER130501).
文摘Three-dimensional(3D)bioprinting,an effective technique for building cell-laden structures providing native extracellular matrix environments,presents challenges,including inadequate cellular interactions.To address these issues,cell spheroids offer a promising solution for improving their biological functions.Particularly,minispheroids with 50-100μm diameters exhibit enhanced cellular maturation.We propose a one-step minispheroid-forming bioprinting process incorporating electrical stimulation(E-MS-printing).By stimulating the cells,minispheroids with controlled diameters were generated by manipulating the bioink viscosity and stimulation intensity.To validate its feasibility,E-MS-printing process was applied to fabricate an engineered liver model designed to mimic the hepatic lobule unit.E-MS-printing was employed to print the hepatocyte region,followed by bioprinting the central vein using a core-shell nozzle.The resulting constructs displayed native liver-mimetic structures containing minispheroids,which facilitated improved hepatic cell maturation,functional attributes,and vessel formation.Our results demonstrate a new potential 3D liver model that can replicate native liver tissues.
