Animals ; Dentistry ; Swine ; Swine, Miniature

All endoureteromy procedures have in common the use of a ureteral stent as post-procedure However, the optimal stent size necessary to promote satisfactory healing is not known. Herein we compared healing of an endoureterotomy over a 7 Fr indwelling ureteral stent (IUS) with healing over a 14 Fr endopyelotomy stent( ES). A mid-ureteral stricture was created in each of 25 anesthetized, female minipigs using a retrograde electrified stone basket. Six weeks later, retrograde ureterograms(RU) revealed a stricture in 24 pigs ; ureteral incision was performed with a 24 Fr cutting balloon device. Twenty pigs were randomized to receive a 7 Fr IUS or a 14 Fr ES; 4 control pigs were performed to confirm proper stent position and the stents were removed. At 3 months. RU was repeated and the ureters were grossly examined and harvested for histological studies. Two pigs in each group had recurrent strictures. Despite a 50 years history of endoureterotomy, optimal stent size remains an endourologic unknown. Our study represents the first attempt at directly comparing stents of different size in an in vivo ureteral stricture model. There is no significant difference between 7 Fr and 14 Fr stents.
Constriction, Pathologic* ; Female ; Humans ; Stents* ; Swine ; Swine, Miniature ; Ureter*

OBJECTIVETo evaluate the effects of a solitary megadose protocol of ionizing radiation (IR) to parotid gland on the structured and function changes of bilateral parotid glands in miniature pig.

METHODSFourteen minipigs were subjected to either 15 or 20 Gy to one parotid gland with a linear accelerator, while another four minipigs served as non-IR controls. Salivary flow rates and salivary chemistries were measured pre-IR, and 4 and 16 weeks post-IR. A quantitative assessment of gland weight and acinar area, and detailed serum chemistry and hematological analyses, were also performed.

RESULTSParotid gland weights were significantly decreased in the 15 and 20 Gy groups at 4 and 16 weeks post-IR. The acinar cell area in glands of both IR groups was significantly reduced. Parotid flow rates decreased by 60% with 15 Gy at 16 weeks post-IR. In the 20 Gy group, salivary flow rates were reduced by 80% at 16 weeks post-IR. Additionally, parotid flow rates significantly reduced in contralateral glands with 20 Gy at 16 weeks, while structure and weight did not changes in parotid glands.

CONCLUSIONStructural changes in salivary gland parenchyma occurred relatively early after IR, while the alterations in salivary output were relatively delayed. Further, reductions in salivary flow were not proportional to acinar cell area loss. There isn't a significant structured change of contralateral glands, but significant reduction of parotid flow rate at this time.

Animals ; Parotid Gland ; radiation effects ; Swine ; Swine, Miniature

BACKGROUNDThe aim of this research was to evaluate the feasibility and efficacy of absorbable bandage wrapping in the treatment of cases of severe liver trauma.

METHODSElectric firecrackers were detonated in 16 miniature swine to produce a severe blast liver injury. After fluid resuscitation, the animals were randomly divided into two groups (n = 8 each) and were either treated with absorbable bandage wrapping of the injured lobe of liver (Group B) or hepatic lobectomy (Group H). Time to hemostasis, blood loss during the treatment period, and other parameters were compared, including postoperative serum total bilirubin (TB), alanine aminotransferase (ALT), and aspartate aminotransferase (AST).

RESULTSBlood loss during the treatment period was significantly lower in Group B than that in Group H ((81.3 ± 26.0) ml vs. (130.8 ± 29.5) ml, P = 0.0031). Serum AST and ALT were transiently increased post-surgically. These transient increases were significantly higher in Group B. No difference in time to hemostasis was noted ((8.70 ± 2.27) minutes vs. (10.28 ± 1.93) minutes, P = 0.1559) in Groups B and H, respectively. Two pigs were humanely euthanized 28 days post-surgically and the wrapped liver lobes appeared atrophies. Microscopically, there was evidence of emerging and mature fibrous tissue.

CONCLUSIONAbsorbable bandage wrapping is both feasible and effective in the treatment of severe blast liver injury.

Animals ; Bandages ; Female ; Liver ; injuries ; surgery ; Male ; Swine ; Swine, Miniature

BACKGROUNDAutologous transplantation of the submandibular gland (SMG) into the temporal fossa with microvascular anastomosis has been successfully applied in severe xerophthalmia patients as a permanent tear substitute. However, severe xerophthalmia can be accompanied by salivary gland dysfunction, making such autotransplantation unsuitable. Therefore, SMG allotransplantation might be a solution. The aim of this study was to assess the technical feasibility of submandibular gland allotransplantation.

METHODSTwelve miniature swine were randomized to serve as donors or recipients. One SMG was transplanted between a donor and a recipient. The donor SMG was revascularized by microvascular anastomosis of its vascular pedicle to the recipient lingual artery and external jugular vein. The secretory duct was implanted into the vestibule of the mouth through a subcutaneous tunnel. No immunosuppressive agent was administered. The results were assessed by visual inspection of the secretion, and histopathological examination of the transplanted SMG.

RESULTSTechnically, all surgical procedures were successful. Clear secretion flowed out of the duct as soon as blood supply of the transplanted submandibular gland was reestablished. The secretion of the gland lasted for 5 days. As expected, an acute rejection reaction occurred after surgery because no immunosuppressive agents were used. Secretion from the transplanted SMG ceased within 5 days.

CONCLUSIONSA model of SMG allotransplantation can be established in miniature swine. The technique of submandibular gland allotransplantation is feasible.

Animals ; Microscopy, Electron ; Models, Animal ; Submandibular Gland ; pathology ; transplantation ; ultrastructure ; Swine ; Swine, Miniature ; Transplantation, Homologous

OBJECTIVETo establish a animal model of biliary leakage in pigs with laparoscopy.

METHODSEight healthy Bama minipigs were subject to laparoscopic surgery under general anesthesia.The cystic duct was resected at 0.5-1.0 cm from the root and the stump was left open with the gallbladder removed. Blood routine and hepatic functions of the pigs were tested before and 24 h after the surgery, and endoscopic retrograde cholangiography (ERC) was performed 24 h after the surgery. At 48 h after the surgery, the pigs were sacrificed for observation of the stump of the cystic duct.

RESULTSThe gallbladder, cystic duct, cystic artery, and the anatomical relations between the gallbladder and liver and between the cystic duct and common bile duct were fully exposed under laparoscopy. White blood cells, neutrophils and direct bilirubin increased significantly after the operation (P<0.05). The cystic ducts were resected at 0.5-1 cm away from the roots of the cystic ducts in 7 pigs and at 2 cm in 1 pig.

CONCLUSIONLaparoscopy is safe and feasible for establishing the porcine model of biliary leakage.

Animals ; Biliary Fistula ; Cystic Duct ; surgery ; Disease Models, Animal ; Female ; Laparoscopy ; Male ; Swine ; Swine, Miniature

OBJECTIVETo establish a neonatal Tibet minipig model of hypoxic-ischemic encephalopathy and evaluate the magnetic resonance imaging (MRI) manifestations and pathological findings.

METHODSSix neonatal (1-3 days old) Tibet minipigs were randomized into model group (n=4) and control group (n=2). In model group, hypoxic-ischemic encephalopathy was induced by surgical ligation of the bilateral carotid artery followedimmediately by hypoxic exposure in a hypoxia chamber for 1 h. ESWAN was performed at 2 h, 24 h, 3 days and 5 days after induction of HIE or at 2 h after sham surgery in the control animals to evaluate the brain damage. Conventional MRI scans (T2FLAIR, T2WI, and DWI) were also performed at 24 h after the modeling.

RESULTSIn the neostriatum, values of T(2)*-weighted MRI increased and reached the peak level at 3 days post-injury (P<0.05). Subcortical white matter T(2)* values reached the peak level at 24 h (P<0.05). Neostriatum R(2)* values were at the lowest level at 3 days (P<0.05). Magnitude values were significantly increased after the model establishment (P<0.05). DWI showed multiple mild focal high signals in the bifrontal subcortical white matter and bilateral neostriatum; T2FLAIR showed slightly increased signal; T2WI showed no obvious abnormalities. SWI showed dilated medulla veins adjacent to the bilateral lateral ventricles and basal ganglia. In the early stage of HIE, brain pathologies were characterized mainly by edema and venous congestion with occasional focal necrosis and hemosiderin deposition.

CONCLUSIONESWAN sequence is capable of detecting bleeding and brain edema, and T(2)*, R(2)*, and magnitude values can be used to estimate the changes of brain damage following HIE.

Animals ; Disease Models, Animal ; Hypoxia-Ischemia, Brain ; diagnosis ; pathology ; Magnetic Resonance Imaging ; Swine ; Swine, Miniature ; Tibet

OBJECTIVETo study scutellarin starch microspheres' permeability through nasal mucosa of different animals in vitro.

METHODThe Franz diffusion cell method was used to experiment the permeability test (n = 4), taking fresh nasal mucosa of dog, swine and domestica in vitro as permeation barrier separately, with scutellarin starch microspheres (scutellarin 0.25 mg) above them, and blank pH 6.8 PBS as absorption liquid to detemine the scutellarin by HPLC.

RESULTThe permeability coefficient of scutellarin starch microspheres through nasal mucosa of dog, swine and domestica in vitro were (5.295 +/- 0.637) x 10(-3) (4.065 +/- 1.140) x 10(-3), (1.855 +/- 0.150) x 10(-3) cm x mL(-1) separately. The permeability coefficient order of scutellarin starch microspheres through nasal mucosa of different animals in vitro is dog > swine > domestica, and there are significant differences between the permeability coefficient of scutellarin starch microspheres through nasal mucosa of dog, swine in vitro, and that through nasal mucosa of swine and domestica in vitro.

CONCLUSIONDrugs in scutellarin starch microspheres could permeate through the above-mentioned nasal mucosa in vitro. There might be different permeability coefficient among different species.

Animals ; Apigenin ; pharmacokinetics ; Dogs ; Glucuronates ; pharmacokinetics ; Microspheres ; Nasal Mucosa ; metabolism ; Permeability ; Starch ; pharmacokinetics ; Swine ; Swine, Miniature

OBJECTIVETo investigate the histologic effect of botulinum toxin type A (Botox A) injection on myocutaneous flap expansion in minipigs model.

METHODSSeven minipigs were included in this study. Two symmetric tattoo area, 10 cm x 6 cm in size, were selected on the bilateral flank of the pigs. The Botox A was injected into one tattoo area randomly, 4 U every point, 2 cm apart, with a total dose of 96 U. The same dose of sterile normal saline (0.9%) was injected in the same fashion on the opposite side as control. 3 days after injection , two 200 ml expanders were inserted beneath the cutaneous muscle at the tattoo area. After complete expansion of 200 ml, the specimens were drawn from both groups symmetrically and were stained by means of HE and Masson. The histologic changes of myocutaneous flap were compared. Thickness of each layer in myocutaneous flap was measured in histological section.

RESULTSThe thickness of cutaneous muscle, capsule, dermis were (275.74 +/- 28.93) microm, (468.03 +/- 34.28) microm, (1990.79 +/- 102.10) microm in Botox group, and (409.13 +/- 44.63) microm, (626.55 +/- 44.05) microm, (2508.44 +/- 70.71) microm in saline group, respectively, show a significant difference between the two groups (P < 0.01). The Masson stained slice showed that collagen average gray of capsule in Botox group was 185.38 +/- 9.56, which was significantly higher than that in the saline group (120.77 +/- 10.31, P < 0.01). Light microscope (HE stained sections ) showed that muscle in Botox group was significantly atrophy and cross-section of muscle fiber decreased. The muscle fiber in saline group was generally normal. It was observed through transmission electron microscope that the light and dark band of muscle cell became fuzzy and the Z line bending in Botox group. The light and dark band in saline group arranged neatly, the Z line was clear.

CONCLUSIONSApplication of Botox A in myocutaneous flap expansion can make the muscle atrophy and reduce the content of collagen in capsule layer, making the myocutaneous flap thinner which is suitable for reconstruction in face and neck.

Animals ; Botulinum Toxins, Type A ; pharmacology ; Female ; Male ; Surgical Flaps ; Swine ; Swine, Miniature ; Tissue Expansion

OBJECTIVETo investigate the relationship of hemorheological parameters between Tibet mini-pigs, Beagle dogs and human.

METHODSBlood samples were collected from adult Tibet mini-pigs, Beagle dogs and human to detect such hemorheological parameters as the whole blood viscosity (WBV) (high, middle, and low shear rate), PV, HCT, ESR and Fi.

RESULTSThe male Tibet mini-pigs had significantly lower WBV (150, 30, 5, and 1 s(-1)) and Fi than the female mini-pigs (P<0.05, 0.01, 0.05, 0.01, and 0.01, respectively). The WBV of male Beagle dogs (150 and 1 s(-1)) was significantly lower that in than female dogs (P<0.05). The WBV of male human subjects (1 s(-1)) and HCT were significantly higher, but ESR significantly lower than those in female human subjects P<0.05, 0.01 and 0.01, respectively). WBV (1 s(-1)), PV, and ESR in Beagle dogs were significantly lower, but HCT and Fi significantly higher than those in Tibet mini-pig and human subjects (P<0.05, 0.01, 0.05, and 0.01, respectively). All the hemorheological parameters were similar between Tibet mini-pigs and human (P<0.05).

CONCLUSIONThe hemorheological parameters of Tibet mini-pigs are closer to those of human than those of Beagle dogs.

Adult ; Animals ; Blood Sedimentation ; Blood Viscosity ; Dogs ; Female ; Hematocrit ; Hemorheology ; Humans ; Male ; Swine ; Swine, Miniature