Objective-To report a technique for correction of atresia ani and rectovestibular fistula with fi... more Objective-To report a technique for correction of atresia ani and rectovestibular fistula with fistula preservation, and outcome in 2 dogs. Study Design-Case report. Animals-Two intact female puppies. Methods-The fistula was approached by episiotomy. A vertical median perineal incision was made starting dorsal to the anal region and extended to surround the fistula. The rectum and vagina were separated, and the end of the fistula was sutured to the skin. Results-Early postoperative complications included constipation, fecal incontinence, and perineal soiling, but long-term outcome was good in both dogs. Conclusion-With careful dissection, the fistula and internal anal sphincter can be preserved and used in the surgical reconstruction of the anal canal and anus. Clinical Relevance-Preservation of the fistula may provide an internal sphincter that contributes to a better functional result during correction of atresia ani. A surgical approach that combines episiotomy and perineal incision for separation of the vagina and rectum, and preserves the fistula may decrease the risk of dehiscence.
To describe the location of the femoral nerve within the iliopsoas muscle and determine the feasi... more To describe the location of the femoral nerve within the iliopsoas muscle and determine the feasibility and potential complications of an ultrasound-guided block. Prospective experimental trial. Sixteen adult dogs, median weight 14.3 (range 3-37) kg. Phase I. Computed tomographic images of the iliopsoas muscle and femoral nerve were analyzed in two dogs. Phase II. The location of the femoral nerve within the iliopsoas muscle was determined via ultrasonography in 11 healthy anaesthetized dogs. Phase III. Peripheral nerve stimulation and ultrasound were combined to perform femoral nerve blocks in three dogs. Using computed tomography, the femoral nerve and its L4-L5 roots were identified within the iliopsoas muscle. The nerve itself was traced until it branched off into the quadriceps femoris muscle. Using ultrasonography, it was possible to observe the femoral nerve in nine dogs (82%). Starting at the dorsal third of the iliopsoas muscle, its path was traced in a caudo-ventro-lateral direction, emerging from the iliopsoas muscle shortly before passing through the muscular lacuna where it became very difficult to identify. An ultrasound-guided femoral nerve approach was carried out successfully in all three dogs. It is possible to approach the femoral nerve using combined ultrasound guidance and peripheral nerve stimulation to a closer proximal point than previously described. The ultrasound-guided approach of the femoral nerve within the iliopsoas muscle has the potential to become an additional approach.
Objective To investigate the anatomy of the brachial plexus, sciatic, and femoral nerves for the ... more Objective To investigate the anatomy of the brachial plexus, sciatic, and femoral nerves for the use of a peripheral nerve-stimulator to perform nerve blocks in dogs. Study design Prospective experimental trial. Animals Four canine cadavers and four healthy adult dogs weighing 23 ± 2.5 kg. Conclusion Electrostimulation of peripheral nerves is useful in locating the branches of the brachial plexus as well as the sciatic and femoral nerves in dogs. Clinical relevance Peripheral nerve stimulation increases the reliability of a nerve block when compared with blind needle-insertion.
Antagonism of low degrees of atracurium-induced neuromuscular blockade: dose-effect relationship ... more Antagonism of low degrees of atracurium-induced neuromuscular blockade: dose-effect relationship for neostigmine. Anesthesiology 112, 34-40. Goldhill DR, Wainwright AP, Stuart CS et al. (1989) Neostigmine after spontaneous recovery from neuromuscular blockade Effect on depth of blockade monitored with train-of-four and tetanic stimuli. Anaesthesia 44, 293-299. Kopman AF, Mallhi MU, Neuman GG et al. (1996) Reestablishment of paralysis using mivacurium following apparent full recovery from mivacurium-induced neuromuscular block. Anaesthesia 51, 41-44.
To analyze the effects of an extracorporeal bioartificial liver containing alginate bead-entrappe... more To analyze the effects of an extracorporeal bioartificial liver containing alginate bead-entrapped hepatocytes on pigs with ischemia-induced acute hepatic failure. Design: Prospective animal study. Setting: University and INSERM laboratory. Subjects: Fifteen Large White/Pietrin female pigs weighing 20-30 kg. Interventions: Acute hepatic failure was induced by end-toside portocaval shunt and ligature of the whole porta hepatitis. The bioartificial liver was in a thermostabilized column, containing a fluidized bed of alginate beads that embedded porcine hepatocytes, connected to a plasmapheresis system. Intracranial pressure; survival; ammonia, total bilirubin, aminotransferases, alkaline phosphatase, and lactate concentrations; and clotting factors were studied. The groups were pigs with acute hepatic failure (group 1, n ؍ 4), pigs with acute hepatic failure treated with bioartificial liver containing empty beads (group 2, n ؍ 4), or porcine hepatocytes (group 3, n ؍ 5). Measurements and Main Results: In group 1, survival of pigs averaged 10.9 ؎ 1.0 hrs; intracranial pressure reached 32.3 ؎ 3.8 mm Hg and was associated with coma and cerebral edema. After connection to the bioartificial liver, the survival of acute hepatic failure pigs was 12.1 ؎ 1.4 hrs in group 2 and 14.8 ؎ 2.5 hrs in group 3. In group 3, intracranial pressure and bilirubin concentrations were reduced significantly compared with both group 1 and group 2. Neither signs of encephalopathy nor cerebral edema was observed in any animal of group 3. In all animals, plasma ammonium, aminotransferases, alkaline phosphatase, and lactate concentrations increased and clotting factors decreased with no significant differences between the three groups. Autopsy revealed a total necrosis of the liver, which was histologically confirmed. Conclusions: The ischemia-induced model of acute hepatic failure in pigs is reproducible and provides measurable clinical and biological features. A bioartificial liver containing alginate beadentrapped hepatocytes improves the signs of encephalopathy in pigs with ischemia-induced acute hepatic failure, suggesting that the bioartificial liver can clear out toxic compounds that are released from necrotic livers.
L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FB... more L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FBE) utilisant des hepatocytes immobilises dans des billes d'alginate de 1 mm. Nos resultats ont montre la superiorite de la technique d'extrusion couplee a une vibration du jet laminaire pour obtenir les billes. Nous avons mis au point une technique de conservation hypothermique des hepatocytes immobilises qui maintient jusqu'a 48h la viabilite et les activites fonctionnelles des hepatocytes. Nos resultats montrent que l'immobilisation dans un gel d'alginate protege les hepatocytes des lesions induites par l'hypothermie a 4ʿC. Des porcs, mis en insuffisance hepatique et branches sur un FBE contenant des hepatocytes immobilises, avaient une esperance de vie augmentee et une augmentation moindre de la pression intracrânienne. La spectroscopie RMN a permis de conclure au maintien du metabolisme de certains composes par le FBE (trimethylamine-N-oxide et choline), ce qui pourrait expliquer les resultats obtenus.
The use of alginate-entrapped cells in cell therapy requires a method for monitoring possible rel... more The use of alginate-entrapped cells in cell therapy requires a method for monitoring possible released compound within biological fluids following either their implantation or inoculation in artificial organs. Oligomannuronic and oligoguluronic acids were prepared by enzymatic depolymerization with alginate lyase from Pseudomonas alginovora, characterized by high-performance anion-exchange chromatography with pulsed amperometric detection and quantitated in human, pig and rabbit blood, urine and tissue samples. The method was tested for linearity and detection limit, accuracy, intra- and inter-day precision. The limit of detection was 3 microgram/ml in both urine and plasma and 5 mg/g of tissues. The relative standard deviations (RSDs) of intra-day precision were 6.0-16.6% and 4.8-8.7% in plasma and urine, respectively; the RSDs of inter-day precision were 5.1-14.4% and 5.0-11.6% in plasma and urine, respectively. Thus, this method appears suitable for the measurement of released alginate from entrapped cells used in cell therapy.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FB... more L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FBE) utilisant des hepatocytes immobilises dans des billes d'alginate de 1 mm. Nos resultats ont montre la superiorite de la technique d'extrusion couplee a une vibration du jet laminaire pour obtenir les billes. Nous avons mis au point une technique de conservation hypothermique des hepatocytes immobilises qui maintient jusqu'a 48h la viabilite et les activites fonctionnelles des hepatocytes. Nos resultats montrent que l'immobilisation dans un gel d'alginate protege les hepatocytes des lesions induites par l'hypothermie a 4ʿC. Des porcs, mis en insuffisance hepatique et branches sur un FBE contenant des hepatocytes immobilises, avaient une esperance de vie augmentee et une augmentation moindre de la pression intracrânienne. La spectroscopie RMN a permis de conclure au maintien du metabolisme de certains composes par le FBE (trimethylamine-N-oxide et choline), ce qu...
Hepatic encephalopathy may occur following acute hepatic failure (AHF), which results in the rele... more Hepatic encephalopathy may occur following acute hepatic failure (AHF), which results in the release of toxic compounds from the injured liver. These compounds, which induce cerebral edema, are not well characterized, yet. The aim of this study was to evaluate the potential interest of NMR spectroscopy in the follow‐up of different plasma compounds in pigs with ischemia‐induced fulminant hepatic failure treated or not with a bioartificial liver (BAL), which has been previously shown to improve the neurological status of the animals. Qualitative analysis of pig plasma was achieved by one‐dimensional‐1H CPMG, two‐dimensional homonuclear 1H‐1H TOCSY CPMG and heteronuclear 1H‐13C HSQC sequences. Semi‐quantitative analysis of selected plasma metabolites along the disease evolution was carried out on pigs with ischemia‐induced AHF treated with the BAL containing alginate beads with or without hepatocytes. A quantitative longitudinal follow‐up was performed on characteristic metabolites vi...
Objective-To report a technique for correction of atresia ani and rectovestibular fistula with fi... more Objective-To report a technique for correction of atresia ani and rectovestibular fistula with fistula preservation, and outcome in 2 dogs. Study Design-Case report. Animals-Two intact female puppies. Methods-The fistula was approached by episiotomy. A vertical median perineal incision was made starting dorsal to the anal region and extended to surround the fistula. The rectum and vagina were separated, and the end of the fistula was sutured to the skin. Results-Early postoperative complications included constipation, fecal incontinence, and perineal soiling, but long-term outcome was good in both dogs. Conclusion-With careful dissection, the fistula and internal anal sphincter can be preserved and used in the surgical reconstruction of the anal canal and anus. Clinical Relevance-Preservation of the fistula may provide an internal sphincter that contributes to a better functional result during correction of atresia ani. A surgical approach that combines episiotomy and perineal incision for separation of the vagina and rectum, and preserves the fistula may decrease the risk of dehiscence.
To describe the location of the femoral nerve within the iliopsoas muscle and determine the feasi... more To describe the location of the femoral nerve within the iliopsoas muscle and determine the feasibility and potential complications of an ultrasound-guided block. Prospective experimental trial. Sixteen adult dogs, median weight 14.3 (range 3-37) kg. Phase I. Computed tomographic images of the iliopsoas muscle and femoral nerve were analyzed in two dogs. Phase II. The location of the femoral nerve within the iliopsoas muscle was determined via ultrasonography in 11 healthy anaesthetized dogs. Phase III. Peripheral nerve stimulation and ultrasound were combined to perform femoral nerve blocks in three dogs. Using computed tomography, the femoral nerve and its L4-L5 roots were identified within the iliopsoas muscle. The nerve itself was traced until it branched off into the quadriceps femoris muscle. Using ultrasonography, it was possible to observe the femoral nerve in nine dogs (82%). Starting at the dorsal third of the iliopsoas muscle, its path was traced in a caudo-ventro-lateral direction, emerging from the iliopsoas muscle shortly before passing through the muscular lacuna where it became very difficult to identify. An ultrasound-guided femoral nerve approach was carried out successfully in all three dogs. It is possible to approach the femoral nerve using combined ultrasound guidance and peripheral nerve stimulation to a closer proximal point than previously described. The ultrasound-guided approach of the femoral nerve within the iliopsoas muscle has the potential to become an additional approach.
Objective To investigate the anatomy of the brachial plexus, sciatic, and femoral nerves for the ... more Objective To investigate the anatomy of the brachial plexus, sciatic, and femoral nerves for the use of a peripheral nerve-stimulator to perform nerve blocks in dogs. Study design Prospective experimental trial. Animals Four canine cadavers and four healthy adult dogs weighing 23 ± 2.5 kg. Conclusion Electrostimulation of peripheral nerves is useful in locating the branches of the brachial plexus as well as the sciatic and femoral nerves in dogs. Clinical relevance Peripheral nerve stimulation increases the reliability of a nerve block when compared with blind needle-insertion.
Antagonism of low degrees of atracurium-induced neuromuscular blockade: dose-effect relationship ... more Antagonism of low degrees of atracurium-induced neuromuscular blockade: dose-effect relationship for neostigmine. Anesthesiology 112, 34-40. Goldhill DR, Wainwright AP, Stuart CS et al. (1989) Neostigmine after spontaneous recovery from neuromuscular blockade Effect on depth of blockade monitored with train-of-four and tetanic stimuli. Anaesthesia 44, 293-299. Kopman AF, Mallhi MU, Neuman GG et al. (1996) Reestablishment of paralysis using mivacurium following apparent full recovery from mivacurium-induced neuromuscular block. Anaesthesia 51, 41-44.
To analyze the effects of an extracorporeal bioartificial liver containing alginate bead-entrappe... more To analyze the effects of an extracorporeal bioartificial liver containing alginate bead-entrapped hepatocytes on pigs with ischemia-induced acute hepatic failure. Design: Prospective animal study. Setting: University and INSERM laboratory. Subjects: Fifteen Large White/Pietrin female pigs weighing 20-30 kg. Interventions: Acute hepatic failure was induced by end-toside portocaval shunt and ligature of the whole porta hepatitis. The bioartificial liver was in a thermostabilized column, containing a fluidized bed of alginate beads that embedded porcine hepatocytes, connected to a plasmapheresis system. Intracranial pressure; survival; ammonia, total bilirubin, aminotransferases, alkaline phosphatase, and lactate concentrations; and clotting factors were studied. The groups were pigs with acute hepatic failure (group 1, n ؍ 4), pigs with acute hepatic failure treated with bioartificial liver containing empty beads (group 2, n ؍ 4), or porcine hepatocytes (group 3, n ؍ 5). Measurements and Main Results: In group 1, survival of pigs averaged 10.9 ؎ 1.0 hrs; intracranial pressure reached 32.3 ؎ 3.8 mm Hg and was associated with coma and cerebral edema. After connection to the bioartificial liver, the survival of acute hepatic failure pigs was 12.1 ؎ 1.4 hrs in group 2 and 14.8 ؎ 2.5 hrs in group 3. In group 3, intracranial pressure and bilirubin concentrations were reduced significantly compared with both group 1 and group 2. Neither signs of encephalopathy nor cerebral edema was observed in any animal of group 3. In all animals, plasma ammonium, aminotransferases, alkaline phosphatase, and lactate concentrations increased and clotting factors decreased with no significant differences between the three groups. Autopsy revealed a total necrosis of the liver, which was histologically confirmed. Conclusions: The ischemia-induced model of acute hepatic failure in pigs is reproducible and provides measurable clinical and biological features. A bioartificial liver containing alginate beadentrapped hepatocytes improves the signs of encephalopathy in pigs with ischemia-induced acute hepatic failure, suggesting that the bioartificial liver can clear out toxic compounds that are released from necrotic livers.
L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FB... more L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FBE) utilisant des hepatocytes immobilises dans des billes d'alginate de 1 mm. Nos resultats ont montre la superiorite de la technique d'extrusion couplee a une vibration du jet laminaire pour obtenir les billes. Nous avons mis au point une technique de conservation hypothermique des hepatocytes immobilises qui maintient jusqu'a 48h la viabilite et les activites fonctionnelles des hepatocytes. Nos resultats montrent que l'immobilisation dans un gel d'alginate protege les hepatocytes des lesions induites par l'hypothermie a 4ʿC. Des porcs, mis en insuffisance hepatique et branches sur un FBE contenant des hepatocytes immobilises, avaient une esperance de vie augmentee et une augmentation moindre de la pression intracrânienne. La spectroscopie RMN a permis de conclure au maintien du metabolisme de certains composes par le FBE (trimethylamine-N-oxide et choline), ce qui pourrait expliquer les resultats obtenus.
The use of alginate-entrapped cells in cell therapy requires a method for monitoring possible rel... more The use of alginate-entrapped cells in cell therapy requires a method for monitoring possible released compound within biological fluids following either their implantation or inoculation in artificial organs. Oligomannuronic and oligoguluronic acids were prepared by enzymatic depolymerization with alginate lyase from Pseudomonas alginovora, characterized by high-performance anion-exchange chromatography with pulsed amperometric detection and quantitated in human, pig and rabbit blood, urine and tissue samples. The method was tested for linearity and detection limit, accuracy, intra- and inter-day precision. The limit of detection was 3 microgram/ml in both urine and plasma and 5 mg/g of tissues. The relative standard deviations (RSDs) of intra-day precision were 6.0-16.6% and 4.8-8.7% in plasma and urine, respectively; the RSDs of inter-day precision were 5.1-14.4% and 5.0-11.6% in plasma and urine, respectively. Thus, this method appears suitable for the measurement of released alginate from entrapped cells used in cell therapy.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FB... more L'objectif de ce travail etait la mise au point d'un foie bioartificiel extracorporel (FBE) utilisant des hepatocytes immobilises dans des billes d'alginate de 1 mm. Nos resultats ont montre la superiorite de la technique d'extrusion couplee a une vibration du jet laminaire pour obtenir les billes. Nous avons mis au point une technique de conservation hypothermique des hepatocytes immobilises qui maintient jusqu'a 48h la viabilite et les activites fonctionnelles des hepatocytes. Nos resultats montrent que l'immobilisation dans un gel d'alginate protege les hepatocytes des lesions induites par l'hypothermie a 4ʿC. Des porcs, mis en insuffisance hepatique et branches sur un FBE contenant des hepatocytes immobilises, avaient une esperance de vie augmentee et une augmentation moindre de la pression intracrânienne. La spectroscopie RMN a permis de conclure au maintien du metabolisme de certains composes par le FBE (trimethylamine-N-oxide et choline), ce qu...
Hepatic encephalopathy may occur following acute hepatic failure (AHF), which results in the rele... more Hepatic encephalopathy may occur following acute hepatic failure (AHF), which results in the release of toxic compounds from the injured liver. These compounds, which induce cerebral edema, are not well characterized, yet. The aim of this study was to evaluate the potential interest of NMR spectroscopy in the follow‐up of different plasma compounds in pigs with ischemia‐induced fulminant hepatic failure treated or not with a bioartificial liver (BAL), which has been previously shown to improve the neurological status of the animals. Qualitative analysis of pig plasma was achieved by one‐dimensional‐1H CPMG, two‐dimensional homonuclear 1H‐1H TOCSY CPMG and heteronuclear 1H‐13C HSQC sequences. Semi‐quantitative analysis of selected plasma metabolites along the disease evolution was carried out on pigs with ischemia‐induced AHF treated with the BAL containing alginate beads with or without hepatocytes. A quantitative longitudinal follow‐up was performed on characteristic metabolites vi...
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