Background:Pulmonary hypertension(PH)is a life-threatening condition that can be triggered by pulmonary thromboembolism(PTE),which causes abrupt increases in pulmonary artery pressure and resistance.Although Doppler e...Background:Pulmonary hypertension(PH)is a life-threatening condition that can be triggered by pulmonary thromboembolism(PTE),which causes abrupt increases in pulmonary artery pressure and resistance.Although Doppler echocardiography is a useful screening tool,its ability to accurately reflect rapid hemodynamic changes during acute PTE remains limited.The Flowire catheter allows for real-time assessment of intravascular flow and may offer better insight into these changes.Aims:The aims were to investigate changes in pulmonary artery hemodynamics measured using a Flowire catheter and to validate the accuracy of Doppler echocardiography in assessing these changes in dogs with acute pulmonary thromboembolism(PTE).Methods:Hemodynamic and echocardiographic data were obtained from 10 anesthetized female beagles using a Flowire catheter and echocardiography at three preload conditions:baseline,bolus loading,and an acute pulmonary hypertension state induced by a 300-μm dextran microsphere injection.Results:With increases in pulmonary artery pressure and pulmonary vascular resistance,the proximal and distal pulmonary artery flow peak measured using the Flowire catheter significantly decreased during the acute pulmonary hypertension period.Echocardiography did not accurately capture these hemodynamic changes and tended to overestimate pulmonary artery flow peak in the distal pulmonary artery.Conclusion:Doppler echocardiography has limitations in accurately reflecting complex hemodynamic changes during acute PTE.In contrast,Flowire catheterization provides additional and precise local hemodynamic information.展开更多
Background: Appropriate preclinical evaluation of a bioartificial liver assist device (BAL) demands a large animal model, as presented here, that demon- strates many of the clinical features of acute liver failure and...Background: Appropriate preclinical evaluation of a bioartificial liver assist device (BAL) demands a large animal model, as presented here, that demon- strates many of the clinical features of acute liver failure and that is suitable for clinical qualitative and quantitative evaluation of the BAL. A lethal canine liver failure model of acute hepatic failure that re- moves many of the artifacts evidenced in prior canine models is presented. Methods: Six male hounds, 24-30 kg, under isoflu- rane anesthesia, were administered 1.5 g/kg D- galactosamine intravenously. Canine supportive care followed a well-defined management protocol that was guided by electrolyte and invasive monitoring consisting of arterial pressure, central venous pres- sure, extradural intracranial pressure (ICP), pul- monary artery pressure, and end-tidal CO_2. The animals were treated until death-equivalent, defined as inability to sustain systolic blood pressure>80 mmHg for 20 minutes despite maximal fluids and 20 μg·kg^(-1)·min^(-1) dopamine infusion. Results: The mean survival time was 43.7±4.6 hours (mean±SE). All animals showed evidence of progressive liver failure characterized by increasing liver enzymes (aspartate transaminase from 26 to 5977 IU/L; alanine transaminase from 32 to 9740 IU/L), bilirubin (0.25 to 1.30 mg/dl), ammonia (19. 8 to 85. 3 μmol/L), and coagulopathy (pro- thrombin time from 8.7 to 46 s). Increased lability and elevations in intracranial pressures were ob- served. All animals were refractory to maintenance of cerebral perfusion pressure even with only mode- rately elevated intracranial pressure. Severe neuro- logic obtundation, seen in 2 of 6 animals, was associ- ated with elevations of ICP above 50 mmHg. Post- mortem liver histology showed evidence of massive hepatic necrosis. Postmortem blood and ascites mi- crobial growth was consistent with possible transloca- tion of intestinal microbes. Conclusions: The improved lethal canine liver failure model presented here reproduces many of the clinical features of acute liver failure. The model may prove useful for qualitative and quantitative evaluation of BALs.展开更多
Background： lntraoperative neuromonitoring （IONM） of the recunent laryngeal nerve （RLN） has been widely applied during thyroid surgery. However, the sale range of stimulation intensity for IONM remains undetermin...Background： lntraoperative neuromonitoring （IONM） of the recunent laryngeal nerve （RLN） has been widely applied during thyroid surgery. However, the sale range of stimulation intensity for IONM remains undetermined, Methods： Total thyroidectomies were performed on twenty dogs, and their RLNs were stimulated with a current of 5 20 mA （step-wise in 5 mA increments） for 1 min. The evoked electromyography （EMG） of vocal muscles before and after supramaximal stimulation were recorded and compared. Acute microstructural morphological changes in the RLNs were observed immediately postoperatively under an electron microscope. Results： The average stimulating threshold for RLNs stimulated with 15 mA and 20 mA showed no significant changes compared to the unstimulated RLNs （15 mA group： 0.320 ± 0.123 mA vs. 0.315 ±0.097 mA, P =0.847; 20 mA group： 0.305 ± 0.101 mA vs. 0.300 ＋ 0.103 mA, P = 0.758）. Similar outcomes were shown in average evoked EMG amplitude （15 mA group： 1,026 ± 268 p.V xs. 1,021 ± 273 p.V, P = 0.834; 20 mA group： 1,162 ± 275 μV vs. 1,200 ± 258μV, P = 0.148）. However, obvious acute microstructural morphological changes were observed in the nerves that were stimulated with 20 mA. Conclusions： A stimulation intensity less than 15 mA might be safe for IONM of the RLN.展开更多
Introduction:Parallel stent-stent grafting is a major endovascular technique used to preserve the supra-aortic branches during thoracic endovascular aortic repair(TEVAR)of aortic pathologies involving the aortic arch....Introduction:Parallel stent-stent grafting is a major endovascular technique used to preserve the supra-aortic branches during thoracic endovascular aortic repair(TEVAR)of aortic pathologies involving the aortic arch.The short-and mid-term results of this technique are satisfactory;however,endoleak remains a major concern.Thus,here we designed a new chimney stent-graft to decrease the endoleak rate.Aim:To testify the feasibility and safety of the new chimney stent-graft system in a canine model.Material and methods:Six Labrador retrievers were used.Pre-operative data were collected and all operations were performed under general anesthesia.The main and chimney stent-grafts were implanted through the abdominal aorta and left subclavian artery approaches,respectively.Completion digital subtraction angiography(DSA)was performed to confirm the immediate outcomes.All dogs were fed separately for 6 months and sacrificed after aortic angiography.The thoracic aorta and the main and chimney stent-grafts were harvested for histopathologic examination.Results:No complications were found in follow-up DSA.All branch arteries were patent.In?ammatory responses were observed around the stent-grafts in 3 experimental animals,and slight hyperplasia was observed in the surrounding tissues compared with the normal vessels.There was no mural thrombus in the stent,endothelial cells were noted on the inner surface of the stent,and thrombus was formed in the outer skirt and gutter area.The histopathologic examinations revealed similar results to those of gross necropsy observations.Conclusions:This study demonstrated the feasibility and safety of the Longuette stent-graft and the first to report a revised stent-graft specific for chimney technique.展开更多
Recently,we read a mini-review published by Jeyaraman et al.The article explored the optimal methods for isolating mesenchymal stromal cells from adipose tissue-derived stromal vascular fraction(SVF).Key factors inclu...Recently,we read a mini-review published by Jeyaraman et al.The article explored the optimal methods for isolating mesenchymal stromal cells from adipose tissue-derived stromal vascular fraction(SVF).Key factors include tissue source,processing techniques,cell viability assessment,and the advantages/disadvantages of autologous vs allogeneic use.The authors emphasized the need for standardized protocols for SVF isolation,ethical and regulatory standards for cell-based therapy,and safety to advance mesenchymal stromal cell-based therapies in human patients.This manuscript shares our perspective on SVF isolation in canines.We discussed future directions to potentiate effective regenerative medicine therapeutics in human and veterinary medicine.展开更多
Traumatic spinal cord injury (SCI) usually results in devastating neurologic deficits and disability. In the United States,approximately 12,500 new cases are reported each year, while an estimated 100,000–140,000 new...Traumatic spinal cord injury (SCI) usually results in devastating neurologic deficits and disability. In the United States,approximately 12,500 new cases are reported each year, while an estimated 100,000–140,000 new cases occur every year in China (National Spinal Cord Injury Statistical Center, 2016).Spinal cord injuries are highly disabling and primarily affect young adults, and therefore create great psychological and financial burden on the affected individuals and their families.展开更多
基金Japan Society for the Promotion of Science,Grant/Award Number:JSPS KAKENHI 24K18010。
文摘Background:Pulmonary hypertension(PH)is a life-threatening condition that can be triggered by pulmonary thromboembolism(PTE),which causes abrupt increases in pulmonary artery pressure and resistance.Although Doppler echocardiography is a useful screening tool,its ability to accurately reflect rapid hemodynamic changes during acute PTE remains limited.The Flowire catheter allows for real-time assessment of intravascular flow and may offer better insight into these changes.Aims:The aims were to investigate changes in pulmonary artery hemodynamics measured using a Flowire catheter and to validate the accuracy of Doppler echocardiography in assessing these changes in dogs with acute pulmonary thromboembolism(PTE).Methods:Hemodynamic and echocardiographic data were obtained from 10 anesthetized female beagles using a Flowire catheter and echocardiography at three preload conditions:baseline,bolus loading,and an acute pulmonary hypertension state induced by a 300-μm dextran microsphere injection.Results:With increases in pulmonary artery pressure and pulmonary vascular resistance,the proximal and distal pulmonary artery flow peak measured using the Flowire catheter significantly decreased during the acute pulmonary hypertension period.Echocardiography did not accurately capture these hemodynamic changes and tended to overestimate pulmonary artery flow peak in the distal pulmonary artery.Conclusion:Doppler echocardiography has limitations in accurately reflecting complex hemodynamic changes during acute PTE.In contrast,Flowire catheterization provides additional and precise local hemodynamic information.
基金This study was partially supported by a grant from Excorp Medical, Inc, Oakdale, MN., Steritek J7000 Intracranial Pressure Monitor provided by Ladd Research Industries, Williston, VT., and Datex Capnomac Ultima Anesthesia Monitor provided by Datex, Helsi
文摘Background: Appropriate preclinical evaluation of a bioartificial liver assist device (BAL) demands a large animal model, as presented here, that demon- strates many of the clinical features of acute liver failure and that is suitable for clinical qualitative and quantitative evaluation of the BAL. A lethal canine liver failure model of acute hepatic failure that re- moves many of the artifacts evidenced in prior canine models is presented. Methods: Six male hounds, 24-30 kg, under isoflu- rane anesthesia, were administered 1.5 g/kg D- galactosamine intravenously. Canine supportive care followed a well-defined management protocol that was guided by electrolyte and invasive monitoring consisting of arterial pressure, central venous pres- sure, extradural intracranial pressure (ICP), pul- monary artery pressure, and end-tidal CO_2. The animals were treated until death-equivalent, defined as inability to sustain systolic blood pressure>80 mmHg for 20 minutes despite maximal fluids and 20 μg·kg^(-1)·min^(-1) dopamine infusion. Results: The mean survival time was 43.7±4.6 hours (mean±SE). All animals showed evidence of progressive liver failure characterized by increasing liver enzymes (aspartate transaminase from 26 to 5977 IU/L; alanine transaminase from 32 to 9740 IU/L), bilirubin (0.25 to 1.30 mg/dl), ammonia (19. 8 to 85. 3 μmol/L), and coagulopathy (pro- thrombin time from 8.7 to 46 s). Increased lability and elevations in intracranial pressures were ob- served. All animals were refractory to maintenance of cerebral perfusion pressure even with only mode- rately elevated intracranial pressure. Severe neuro- logic obtundation, seen in 2 of 6 animals, was associ- ated with elevations of ICP above 50 mmHg. Post- mortem liver histology showed evidence of massive hepatic necrosis. Postmortem blood and ascites mi- crobial growth was consistent with possible transloca- tion of intestinal microbes. Conclusions: The improved lethal canine liver failure model presented here reproduces many of the clinical features of acute liver failure. The model may prove useful for qualitative and quantitative evaluation of BALs.
文摘Background： lntraoperative neuromonitoring （IONM） of the recunent laryngeal nerve （RLN） has been widely applied during thyroid surgery. However, the sale range of stimulation intensity for IONM remains undetermined, Methods： Total thyroidectomies were performed on twenty dogs, and their RLNs were stimulated with a current of 5 20 mA （step-wise in 5 mA increments） for 1 min. The evoked electromyography （EMG） of vocal muscles before and after supramaximal stimulation were recorded and compared. Acute microstructural morphological changes in the RLNs were observed immediately postoperatively under an electron microscope. Results： The average stimulating threshold for RLNs stimulated with 15 mA and 20 mA showed no significant changes compared to the unstimulated RLNs （15 mA group： 0.320 ± 0.123 mA vs. 0.315 ±0.097 mA, P =0.847; 20 mA group： 0.305 ± 0.101 mA vs. 0.300 ＋ 0.103 mA, P = 0.758）. Similar outcomes were shown in average evoked EMG amplitude （15 mA group： 1,026 ± 268 p.V xs. 1,021 ± 273 p.V, P = 0.834; 20 mA group： 1,162 ± 275 μV vs. 1,200 ± 258μV, P = 0.148）. However, obvious acute microstructural morphological changes were observed in the nerves that were stimulated with 20 mA. Conclusions： A stimulation intensity less than 15 mA might be safe for IONM of the RLN.
文摘Introduction:Parallel stent-stent grafting is a major endovascular technique used to preserve the supra-aortic branches during thoracic endovascular aortic repair(TEVAR)of aortic pathologies involving the aortic arch.The short-and mid-term results of this technique are satisfactory;however,endoleak remains a major concern.Thus,here we designed a new chimney stent-graft to decrease the endoleak rate.Aim:To testify the feasibility and safety of the new chimney stent-graft system in a canine model.Material and methods:Six Labrador retrievers were used.Pre-operative data were collected and all operations were performed under general anesthesia.The main and chimney stent-grafts were implanted through the abdominal aorta and left subclavian artery approaches,respectively.Completion digital subtraction angiography(DSA)was performed to confirm the immediate outcomes.All dogs were fed separately for 6 months and sacrificed after aortic angiography.The thoracic aorta and the main and chimney stent-grafts were harvested for histopathologic examination.Results:No complications were found in follow-up DSA.All branch arteries were patent.In?ammatory responses were observed around the stent-grafts in 3 experimental animals,and slight hyperplasia was observed in the surrounding tissues compared with the normal vessels.There was no mural thrombus in the stent,endothelial cells were noted on the inner surface of the stent,and thrombus was formed in the outer skirt and gutter area.The histopathologic examinations revealed similar results to those of gross necropsy observations.Conclusions:This study demonstrated the feasibility and safety of the Longuette stent-graft and the first to report a revised stent-graft specific for chimney technique.
基金Supported by the Department of Biotechnology,Ministry of Science and Technology,Government of India,New Delhi,No.BT/PR42179/AAQ/1/814/2021SERB-State University Research Excellence,No.SUR/2022/001952.
文摘Recently,we read a mini-review published by Jeyaraman et al.The article explored the optimal methods for isolating mesenchymal stromal cells from adipose tissue-derived stromal vascular fraction(SVF).Key factors include tissue source,processing techniques,cell viability assessment,and the advantages/disadvantages of autologous vs allogeneic use.The authors emphasized the need for standardized protocols for SVF isolation,ethical and regulatory standards for cell-based therapy,and safety to advance mesenchymal stromal cell-based therapies in human patients.This manuscript shares our perspective on SVF isolation in canines.We discussed future directions to potentiate effective regenerative medicine therapeutics in human and veterinary medicine.
基金supported by the key Research Program of the Chinese Academy of Sciences (ZDRW-ZS-2016-2)the"Strategic Priority Research Program of the Chinese Academy of Sciences"(XDA01030000)
文摘Traumatic spinal cord injury (SCI) usually results in devastating neurologic deficits and disability. In the United States,approximately 12,500 new cases are reported each year, while an estimated 100,000–140,000 new cases occur every year in China (National Spinal Cord Injury Statistical Center, 2016).Spinal cord injuries are highly disabling and primarily affect young adults, and therefore create great psychological and financial burden on the affected individuals and their families.
