OBJECTIVE: To explore the construction of a canine model of vascularized allogeneic spinal cord transplantation (vASCT) and preliminarily evaluate its therapeutic efficacy for spinal cord injury (SCI). METHODS: Sixteen female Beagle dogs aged 8-12 months were randomly selected, with 8 dogs serving as donors for the harvesting of spinal cord tissue with a vascular pedicle [dorsal intercostal artery (DIA) at the T₁₀ level and accompanying vein]. The remaining 8 dogs underwent a 1.5-cm-length spinal cord defect at the T₁₀ level, followed by transplantation of the donor spinal cord tissue for repair. Polyethylene glycol (PEG) was applied to both ends to spinal cord graft; then, using a random number table method, the dogs were divided into an experimental group (n=4) and a control group (n=4). The experimental group received immunosuppressive intervention with oral tacrolimus [0.1 mg/(kg∙d)] postoperatively, while the control group received no treatment. The operation time and ischemia-reperfusion time of two groups were recorded. The recovery of hind limb function was estimated by Olby score within 2 months after operation; the motor evoked potentials (MEP) was measured through neuroelectrophysiological examination, and the spinal cord integrity was observed through MRI. RESULTS: There was no significant difference in the operation time and ischemia-reperfusion time between the two groups (P>0.05). All dogs survived until the completion of the experiment. Within 2 months after operation, all dogs in the control group failed to regain the movement function of hind limbs, and Olby scores were all 0. In the experimental group, the movement and weight-bearing, as well as walking abilities of the hind limbs gradually recovered, and the Olby scores also showed a gradually increasing trend. There was a significant difference between the two groups from 3 to 8 weeks after operation (P<0.05). Neuroelectrophysiological examination indicated that the electrical signals of the experimental group passed through the transplanted area, and the latency was shortened compared to that at 1 month after operation (P<0.05), showing continuous improvement, but the amplitude did not show significant improvement (P>0.05). The control group was unable to detect any MEP changes after operation. MRI examination showed that the transplanted spinal cord in the experimental group survived and had good continuity with normal spinal cord tissue, while no relevant change was observed in the control group. CONCLUSION The vASCT model of dogs was successfully constructed. This surgical procedure can restore the continuity of the spinal cord. The combination of tacrolimus anti-immunity is a key factor for the success of transplantation.
Animals ; Dogs ; Female ; Spinal Cord/blood supply* ; Spinal Cord Injuries/surgery* ; Transplantation, Homologous ; Disease Models, Animal ; Recovery of Function ; Plastic Surgery Procedures/methods* ; Tacrolimus ; Immunosuppressive Agents

PURPOSE: Hand-sewn anastomosis as the gold standard of vascular anastomosis cannot fully meet the requirements of vascular anastomosis in speed and quality. Various vascular couplers have been developed to ameliorate this situation. Most of them are mainly used for venous anastomosis rather than arterial anastomosis. Although it is generally acknowledged that in almost all operations involving vascular reconstruction, it is the arteries that need to be anastomosed faster and more accurately and not the veins. A dedicated device is needed for creating arterial anastomosis in an easy, timesaving, less damaging but reliable procedure. Therefore, we plan to develop a novel arterial coupler device and test pre-clinical safety and effectiveness. METHODS: In this cohort study, the rationality of this novel arterial coupler was preliminarily tested by finite element analysis before it was manufactured. Several factors restrict the use of vascular couplers in arterial anastomosis, such as arterial eversion, fixation, etc. The manufactured arterial couplers underwent in vitro and in vivo experiments. In vitro, isolated arteries of beagles were anastomosed with the assistance of an arterial coupler, and the anastomosed arteries were evaluated through anti-traction tests. In animal experiments, the bilateral femoral arteries of 5 beagles served as a control group. After dissection, the femoral artery on one side was randomly selected to be anastomosed with a quick arterial coupler (QAC) (QAC group), and the femoral artery on the other side was anastomosed by the same person using an end-to-end suture technique with a 6-0 Prolene suture (suture group). The bilateral femoral arteries of 5 beagles were used for coupler-assisted anastomosis and hand-sewn anastomosis in vivo, respectively. Success rate, blood loss, anastomotic time, clamp time, total operation time, and patency rate were recorded. The patency of anastomosed arteries was assessed using vascular Doppler ultrasound, electromagnetic flowmeter, and pathological examination (6 weeks after surgery). RESULTS: As a novel arterial coupler, QAC was successfully designed and manufactured by using poly lactic-co-glycolic acid raw materials and 3-dimensions printing technology. Its rationality was preliminarily tested through finite element analysis and related mechanical analysis methods. The isolated arteries were successfully anastomosed with the assistance of QAC in vitro testing, which showed good anti-traction properties. In animal studies, QAC-assisted arterial anastomosis has superior profiles compared to hand-sewn anastomosis in anastomotic time (7.80 ± 1.41 vs. 16.38 ± 1.04 min), clamp time (8.80 ± 1.41 vs. 14.14 ± 1.57 min), and total operation time (46.64 ± 2.38 vs. 51.96 ± 3.65 min). The results of electromagnetic flowmeter, vascular Doppler ultrasound, and pathological examination showed that QAC-assisted anastomotic arteries were superior to hand-sewn arteries in terms of postoperative blood flow (16.86 ± 3.93 vs. 10.36 ± 0.92 mL/min) and vascular patency in 6 weeks after surgery. CONCLUSION QAC is a well-designed and easily maneuverable device specialized for end-to-end arterial anastomosis. Application of this device may decrease thermal ischemia time and improve the patency of anastomotic arteries, thus, improving outcomes.
Animals ; Anastomosis, Surgical/instrumentation* ; Dogs ; Femoral Artery/surgery* ; Vascular Surgical Procedures/instrumentation* ; Finite Element Analysis

Objective: To explore the short-term efficacy of fenestrated atrial septal defect (ASD) occulders in the treatment of pulmonary arterial hypertension (PAH). Methods: Thirty-six healthy dogs were divided into the balloon atrial septostomy (BAS)+fenestrated ASD occulders group (n=12), BAS group (n=12) and non-septostomy group (n=12). PAH was induced by intra-atrial injection of dehydrogenized monocrotaline (1.5 mg/kg) in all dogs. Animals in the BAS+fenestrated ASD occulders group underwent atrial septal puncture and fenestrated ASD occulders implantation. Animals in the BAS group underwent balloon atrial septostomy. The non-septostomy group received no surgical intervention. The hemodynamic indexes and blood N-terminal pro-B-type natriuretic peptide (NT-proBNP) of dogs were measured before modeling, 2 months after modeling, 1, 3, and 6 months after surgery, respectively. Echocardiography was performed to observe the patency of the shunt and atrial septostomy of the dogs in the BAS+fenestrated ASD occulders group and BAS group at 1, 3, and 6 months after surgery. Three dogs were sacrificed in each group at 1, 3, and 6 months after surgery, respectively. Atrial septal tissue and fenestrated ASD occulders were removed to observe the patency and endothelialization of the device. Lung tissues were obtained for hematoxylin-eosin (HE) staining to observe the inflammatory cells infiltration and the thickening and narrowing of the pulmonary arterials. Results: Among 36 dogs, 2 dogs died within 24 hours after modeling, and 34 dogs were assigned to BAS+fenestrated ASD occulders group (n=12), BAS group (n=11), and non-septostomy group (n=11). Compared with BAS group, the average right atrial pressure (mRAP) and NT-proBNP of dogs in the BAS+fenestrated ASD occulders group were significantly reduced at 3 months after surgery (P<0.05), and the cardiac output (CO) was significantly increased at 6 months after surgery, arterial oxygen saturation (SaO₂) was also significantly reduced (P<0.05). Compared with non-septostomy group, dogs in the BAS+fenestrated ASD occulders group had significantly lower mRAP and NT-proBNP at 1, 3, and 6 months after surgery (P<0.05), and higher CO and lower SaO₂ at 6 months after surgery (P<0.05). Compared with the non-septostomy group, the dogs in the BAS group had significantly lower mRAP and NT-proBNP at 1 month after surgery (P<0.05), and there was no significant difference on mRAP and NT-proBNP at 3 and 6 months after surgery (P>0.05). Echocardiography showed that there was a minimal right-to-left shunt in the atrial septum in the BAS group at 1 month after the surgery, and the ostomy was closed in all the dogs in the BAS group at 3 months after the surgery. There was still a clear right-to-left shunt in the dogs of BAS+fenestrated ASD occulders group. The shunt was well formed and satisfactory endothelialization was observed at 1, 3 and 6 months after surgery. The results of HE staining showed that the pulmonary arterials were significantly thickened, stenosis and collapse occurred in the non-septostomy group. Pulmonary microvascular stenosis and inflammatory cell infiltration in the pulmonary arterials were observed in the non-septostomy group. Pulmonary arterial histological results were comparable between BAS+fenestrated ASD occulders group and non-septostomy group at 6 months after surgery . Conclusions: The fenestrated ASD occulder has the advantage of maintaining the open fistula hole for a longer time compared with simple balloon dilation. The fenestrated ASD occulder can improve cardiac function, and it is safe and feasible to treat PAH in this animal model.
Animals ; Atrial Septum/surgery* ; Cardiac Catheterization/methods* ; Dogs ; Familial Primary Pulmonary Hypertension ; Heart Septal Defects, Atrial/surgery* ; Hypertension, Pulmonary ; Pulmonary Arterial Hypertension

Objective: To evaluate the effectiveness of mucosal flap combined with silicone keel for preventing and treating anterior commissure adhesion in canines and clinical cases. Methods: A prospective experiment was performed from November 2019 to June 2021. Twenty five canines were randomly divided into 5 groups(A, B, C, D, E). Group A, B, C, D received anterior commissure injury by CO₂ laser, then separately treated with free mucosal flap-keel complex,intralaryngeal mucosal flap-keel complex, silicone keels and without treatment, group E didn't injure the vocal cord after intubation. The keel was removed after 2 weeks, the larynx was harvested after 4 weeks. The effectiveness of anterior commissure adhesion prevention was evaluated by manifestation under laryngoscope, standard vocal cord length and standard glottic area. A retrospective analysis was performed on sixteen patients with anterior commissure lesion, who underwent mucosal flap-keel technique in Huashan Hospital of Fudan University from January 2019 to January 2021 (10 cases with free mucosal flap-keel complex and 6 cases with intralaryngeal mucosal flap-keel complex). All the patients underwent evaluation of laryngeal function included manifestation under laryngoscope each month and voice analysis before and 3 month after surgery. SPSS 20.0 software was used for statistical analysis. Results: No surgery accident or complication happened in canines and patients. The standard vocal cord length and standard glottic area after 4 weeks in group B were significantly higher than those in group A, C, D (H_{standard vocal cord length}=31.688, H_{standard glottic area}=16.444, P<0.05). The standard vocal cord length and standard glottic area after 4 weeks in group A were also significantly higher than those in group C, D(H_{standard vocal cord length}=20.936, H_{standard glottic area}=11.786, P<0.05). The standard vocal cord length and standard glottic area after 4 weeks in group A, B, E were not significantly different to that before surgery(t_{A left standard vocal cord length}=2.636, t_{A right standard vocal cord length}=2.582, t_{B left standard vocal cord length}=2.707, t_{B right standard vocal cord length}=2.673, t_{E left standard vocal cord length}=0.370, t_{E right standard vocal cord length}=0.821, t_{A standard glottic area}=2.731, t_{B standard glottic area}=2.753, t_{E standard glottic area}=-0.529, P>0.05). The standard vocal cord length and standard glottic area after 4 weeks in group C, D were significantly lower than those before surgery(t_{C left standard vocal cord length}=16.137, t_{C right standard vocal cord length}=13.984, t_{D left standard vocal cord length}=11.903, t_{D right standard vocal cord length}=14.587, t_{C standard glottic area}=10.280, t_{D standard glottic area}=22.974, P<0.05). During 6-18 months of follow-up in clinical patients, no one developed a glottic web. Three months after surgery, Jitter, Shimmer, noise to harmonic ratio(NHR), the maximum phonation time(MPT)in all patients were significantly different from preoperative(t_{intralaryngeal mucosal flap jitter}=24.885, t_{intralaryngeal mucosal flap shimmer}=22.643, t_{intralaryngeal mucosal flap NHR}=6.202, t_{intralaryngeal mucosal flap MPT}=-9.661, t_{free mucosal flap jitter}=25.459, t_{free mucosal flap shimmer}=18.683, t_{free mucosal flap NHR}=5.705, t_{free mucosal flap MPT}=-20.840, P<0.05). Conclusion: Mucosal flap combined with silicone keel is an effective technique for preventing and treating anterior commissure adhesion. The effect of pedicled intralaryngea lmucosal flap is better.
Animals ; Dogs ; Free Tissue Flaps ; Glottis ; Humans ; Laryngeal Neoplasms/surgery* ; Prospective Studies ; Retrospective Studies ; Vocal Cords/surgery*

OBJECTIVE: To evaluate the type of wound healing following modified crown lengthening surgery in dog model to provide a biological basis for its clinical application. METHODS: Flap surgery, traditional crown lengthening procedure and modified crown lengthening procedure were performed on the right maxillary central incisor, the left maxillary central incisor and the left maxillary first lateral incisor respectively of five male beagle dogs. The right maxillary first lateral incisors with no surgical intervention were used as controls. Thirty-six weeks after the experimental procedure, tissue blocks were harvested and prepared for histological examination and analysis. RESULTS: Histometric examination of buccolingual sections stained with hematoxylin-eosin demonstrated that the type of wound healing in the flap surgery group was re-attachment, similar to the control group. For the traditional crown lengthening surgery group, all of the five beagle dogs had lamellar cementum defects on root surface, the wound healing of four beagle dogs was new attachment accompanied by new cementum formation at cementum defect areas and the suprac-restal connective tissue was functionally oriented perpendicular to the new cementum. The wound healing of the other beagle dog was long junctional epithelial attachment, in which the junctional epithelium extended to the apical terminus of the cementum defect. In the modified crown lengthening surgery group, four beagle dogs had cementum defects on root surface (two lamellar cementum defects and two shallow platform-like cementum defects), the wound healing of three beagle dogs was new attachment, however, the supracrestal connective tissue was parallel to the root surface. The type of wound healing of another one beagle dog was long junctional epithelial attachment. Wound healing of one beagle dog in this group could not be characterized due to incomplete dissection. CONCLUSION Wound healing in the modified crown lengthening surgery group was similar to the traditional crown lengthening surgery group, and two types of wound healing were observed: new attachment and long junctional epithelium attachment. Neither type of root treatment procedure (root planing or root reshaping) nor root surface defect pattern (the lamellar cementum defect or shallow platform-like cementum defect) influenced the observed type of wound healing.
Animals ; Connective Tissue ; Crown Lengthening ; Dogs ; Eosine Yellowish-(YS) ; Epithelial Attachment/pathology* ; Hematoxylin ; Male ; Tooth Root/surgery* ; Wound Healing

BACKGROUND: The effectiveness of bronchial thermoplasty (BT) has been reported in patients with severe asthma. This study compared the effects of BT and cryoballoon ablation (CBA) therapy on the airway smooth muscle (ASM). METHODS: Eight healthy male beagle dogs were included in this experiment. In the preliminary experiment, one dog received BT treatment for both lower lobe bronchus, another dog received CBA treatment for 7 s on the upper and lower lobe of right bronchus, and 30 s on the left upper and lower lobe. The treatments were performed twice at an interval of 1 month. In subsequent experiments, the right lower lobe bronchus was treated with BT, and the left lower lobe bronchus was treated with CBA. The effects of treatment were observed after 1 (n = 3) month and 6 months (n = 3). Hematoxylin-eosin staining, Masson trichrome staining, and immunohistochemical staining were used to compare the effects of BT and CBA therapy on the ASM thickness, collagen fibers synthesis, and M3 receptor expression after treatment. One-way analysis of variance with Dunnett post hoc test was used to analyze the differences among groups. RESULTS: In the preliminary experiment, the ASM ablation effect of 30-s CBA was equivalent to that of 7-s CBA (ASM thickness: 30.52 ± 7.75 μm vs. 17.57 ± 15.20 μm, P = 0.128), but the bronchial mucociliary epithelium did not recover, and large numbers of inflammatory cells had infiltrated the mucosal epithelium at 1-month post-CBA with 30-s freezing. Therefore, we chose 7 s as the CBA treatment time in our follow-up experiments. Compared with the control group (35.81 ± 11.02 μm), BT group and CBA group (13.41 ± 4.40 μm and 4.81 ± 4.44 μm, respectively) had significantly decreased ASM thickness after 1 month (P < 0.001). Furthermore, the ASM thickness was significantly lower in the 1-month post-CBA group than in the 1-month post-BT group (P = 0.015). There was no significant difference in ASM thickness between the BT and CBA groups after six months (9.92 ± 4.42 μm vs. 7.41 ± 7.20 μm, P = 0.540). Compared with the control group (0.161 ± 0.013), the average optical density of the ASM M3 receptor was significantly decreased in 6-month post-BT, 1-month post-CBA, and 6-month post-CBA groups (0.070 ± 0.022, 0.072 ± 0.012, 0.074 ± 0.008, respectively; all P < 0.001). There was no significant difference in the average optical density of ASM M3 receptor between the BT and CBA therapy groups after six months (P = 0.613). CONCLUSIONS CBA therapy effectively ablates the ASM, and its ablation effect is equivalent to that of BT with a shorter onset time. A neural mechanism is involved in both BT and CBA therapy.
Animals ; Bronchi/surgery* ; Bronchial Thermoplasty ; Bronchoscopy ; Cryosurgery ; Dogs ; Humans ; Male ; Muscle, Smooth

OBJECTIVE: To evaluate the effect of two barrier membranes [multilaminated small intestinal submucosa (mSIS) and bioresorable collagen membrane (Bio-Gide)] combined with deproteinized bovine bone mineral Bio-Oss on guided bone regeneration through a canine extraction sockets model. METHODS: The distal roots of 18 premolars of the Beagle' s bilateral maxillary and mandibular were removed, and 18 extraction sockets were obtained. They were randomly divided into 3 groups, and the following procedures were performed on the sockets: (1) filled with Bio-Oss and covered by mSIS (mSIS group), (2) filled with Bio-Oss and covered by Bio-Gide (BG group), (3) natural healing (blank control group). Micro-computed tomograph (Micro-CT) was performed 4 and 12 weeks after surgery to eva-luate the new bone regeneration in the sockets of each group. RESULTS: The postoperative healing was uneventful in all the animals, and no complications were observed through the whole study period. Micro-CT analysis showed that the new bone fraction in the mSIS group and the BG group was significantly higher than that in the blank control group at the end of 4 weeks and 12 weeks (P < 0.05), and more new bone fraction was observed in the mSIS group than in the BG group, but the difference was not statistically significant (P>0.05). The new bone fraction of coronal third part of the socket in the mSIS group and BG group at the end of 4 weeks were significantly higher than that of the middle and apical third part of each group (P < 0.05). The values of bone mineral density were similar at 4 weeks in all the groups (P>0.05), but were significantly higher than that in the control group at the end of 12 weeks (P < 0.05). The bone morphometric analysis showed that the trabecular number and trabecular spacing were significantly better in the mSIS group and the BG group than in the control group at the end of 4 weeks and 12 weeks (P < 0.05), while the value in the mSIS group was slightly higher than in the BG group, but the difference was not statistically significant (P>0.05). The difference in trabecular thickness between all the groups was not statistically significant (P>0.05). CONCLUSION mSIS membrane as a barrier membrane combined with deproteinized bovine bone mineral can enhance new bone formation in canine extraction sockets, similar to Bio-Gide collagen membrane.
Animals ; Bone Regeneration ; Bone Substitutes ; Cattle ; Dogs ; Membranes, Artificial ; Minerals ; Tooth Extraction ; Tooth Socket/surgery* ; X-Ray Microtomography

Amputation ; Animals ; Atrial Appendage/surgery* ; Atrial Fibrillation ; Dogs ; Echocardiography, Transesophageal ; Stroke ; Surgical Instruments

The paper outlines the achievements and challenges in the additive manufacturing (AM) application to veterinary practice. The state-of-the-art in AM application to the veterinary surgery is presented, with the focus of AM for patient-specifi c implants manufacturing. It also provides critical discussion on some of the potential issues design and technology should overcome for wider and more eff ective implementation of additively manufactured parts in veterinary practices. Most of the discussions in present paper are related to the metallic implants, manufactured in this case using so-called powder bed additive manufacturing (PB-AM) in titanium alloy Ti–6AL–4V, and to the corresponding process of their design, manufacturing and implementation in veterinary surgery. Procedures of the implant design and individualization for veterinary surgery are illustrated basing on the four performed surgery cases with dog patients. Results of the replacement surgery in dogs indicate that individualized additively manufactured metallic implants signifi cantly increase chances for successful recovery process, and AM techniques present a viable alternative to amputation in a large number of veterinary cases. The same time overcoming challenges of implant individualization in veterinary practice signifi cantly contributes to the knowledge directly relevant to the modern medical practice. An experience from veterinary cases where organ-preserving surgery with 3D-printed patient-specifi c implants is performed provides a unique opportunity for future development of better human implants.
Alloys ; Amputation ; Animals ; Dogs ; Humans ; Osteosarcoma ; Surgery, Veterinary ; Titanium

OBJECTIVE: To investigate the safety of the controllable ileostomy with pipe in view of histology. METHODS: Twenty-eight Beagle dogs undergoing controllable ileostomy with pipe were studied. The special fistula tube with balloon was placed into the hole locating at the cecal root opposing the mesenteric side, and fixed by double knot compression method. RESULTS: The fistula tube was removed 14 days after surgery, then the safety of the procedure was preliminarily evaluated by gastrointestinal radiography and anatomical observation. The small intestine tissue at the compression suture was used as the experimental segment, and the small intestine tissue at the proximal non-compression suture was used as the control segment. The histological staining and the immunohistochemical staining of S-100 protein, c-kit protein and α-smooth muscle actin(α-SMA) protein between two segment were compared, while quantitative comparison of myenteric plexus, intestinal Cajal cell(ICC) and smooth muscle cells in intestinal wall was carried out. After removal of fistula tube at 14 days postoperative, the dogs were normal in feeding and defecation. The digestive tract radiography showed that the intestine was patent without obvious stenosis and obstruction. The dogs were dissected 21 days after operation. The abdominal sinus ostium was well healed and the internal sinus was well formed. Under gross inspection, blood supply, morphology and motor function of experimental intestine segment were similar from the proximal and distal segments of control intestine. S-100 immunohistochemical staining showed that the morphology and distribution of S-100 protein positive cells and "blank area" cells in the experimental and control segments were consistent. Myenteric plexus counting showed that the experimental segment was 3.62±1.82/field and the control segment was 3.27±1.62/field, whose difference was not statistically significant(t=1.30, P=0.20). Immunohistochemical staining of c-kit showed that the distribution of c-kit positive cells in both segments was consistent. Counting of the number of ICCs in myenteric plexus revealed that experimental segment was 2.96±2.57/plexus, and control segment was 2.49±1.80/plexus without significant difference(t=1.81, P=0.07). Immunohistochemical staining of α-SMA showed that the morphology and distribution of smooth muscle cells in whole intestinal wall(muscle layer, longitudinal muscle, ring muscle) in experimental and control segments were consistent. The average absorbance(A) value of α-SMA staining in ring muscle layer was detected and quantified. The experimental segment was 0.15±0.03 and control segment was 0.14±0.04 without significant difference(t=1.16, P=0.25). CONCLUSION The technique of controllable ileostomy with pipe is safe in view of histology, which may replace the traditional protective ileostomy.
Animals ; Dogs ; Ileostomy ; methods ; standards ; Intestine, Small ; surgery ; Models, Animal ; Proto-Oncogene Proteins c-kit ; metabolism ; Treatment Outcome