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

The production of miniature animals has been suggested for use in organ transplantation. At present, many of the studies about application of animal organs to human have been focused on pigs because of the number of advantages involved and due to their similarities with human. However, a physiological analysis of the organs to be transplanted has not yet been carried out. Therefore, this study analyzed whether or not there were physiological and morphological differences in the hearts of conventionallyreared pigs and micropigs. In this study, the morphological and physiological functions of the heart were examined using radiographic and echocardiographic equipment. In the lateral radiographic view, the heart of the micropig has a larger cardiac long axis : short axis ratio than does the conventional pig, but the difference in the vertebral heart score was not significant. In addition, there were no morphological differences on the X-ray fluoroscopic view. There were no differences in echocardiographic values, except for several values in the left ventricle traces. Overall, it is expected that the values measured in this study will contribute to understanding of the physiological characteristics of micropigs.
Animals ; Echocardiography/veterinary ; Fluoroscopy/veterinary ; Heart/*physiology/*radiography ; Stroke Volume/physiology ; Swine ; Swine, Miniature

Objectives: To examine the impact of probiotics on the lung development of preterm birth of Bama pig. Methods: From April 2020 to October 2021, this animal experimental research was performed by setting up preterm (birth at gestation 104 d), full-term (birth at gestation 113 d), preterm with probiotics (birth at gestation 104 d treated with probiotics given at 3 d after birth), and full-term with probiotics (birth at gestation 113 d treated with probiotics given at 3 d after birth) groups and using the preterm Bama minipig model, the body weights were recorded and lung, ileum, and intestinal content samples were collected at birth, 4 days, 9 days, and 21 days after births of the piglets in preterm and full-term groups, the same samples were collected on 9 days after births of the piglets in preterm with probiotics and full-term with probiotics groups. The body weight and radial alveolar counts (RAC) were compared to evaluate the lung development of the piglets. The lengths of ileal villus were compared to evaluate the development of ileum. The composition structures of bacteria in ileum were analyzed by 16 S rRNA sequencing. The statistical analyses between different groups were performed by t test. Results: There were totally 30 piglets (16 female piglets and 14 male piglets) involving 12 piglets in preterm and full-term groups respectively and 3 piglets in preterm with probiotics and full-term with probiotics groups respectively. The body weights of the piglets in preterm group were lower than those in full-term group at 4, 9 and 21 d after birth ((507±27) vs. (694±56) g, (620±35) vs. (1 092±154) g, (1 660±210) vs. (2 960±418) g,t=2.96, 2.99, 2.78, all P<0.05). The alveolarization of the preterm piglets at 9 days after birth was significantly lower than that of the full-term piglets at the equivalent time point (4.00±0.29 vs. 6.11±0.35, t=4.64, P<0.01). The bacteria genus with the highest abundance in ileum were all different between the preterm and the full-term groups at 4, 9 and 21 d after birth (4 d Escherichia-Shigella (26.63%) and Enterococcus (30.48%) respectively;9 d Turicibacter (35.94%) and Lactobacillus (27.33%) respectively;21 d Escherichia-Shigella (28.02%) and Lactobacillus (46.29%) respectively). The heights of ileal villus of the preterm piglets at 9 d after birth were significantly lower than those of the full-term minipigs at the equivalent time point ((297±21) vs. (411±32) μm, t=3.01, P=0.007).There were both no differences in the body weight and alveolarization ((692±36) vs. (767±67) g, 5.44±0.34 vs. 5.89±0.26, t=0.74, 1.04, both P>0.05) between the piglets in preterm with probiotics group and those in full-term with probiotics group. Turicibacter was the dominant genus in the piglets of both preterm with probiotics and the full-term with probiotics groups. The heights of ileal villus of the piglets in preterm with probiotics group were significantly longer that those of the piglets in preterm group ((371±13) vs. (297±21) μm, t=3.04, P=0.006), and were both not significantly different from those of the piglets in full-term with probiotics group and full-term group ((371±13) vs. (338±12) and (411±32) μm, t=1.90, 1.15, both P>0.05). Conclusions: Premature birth could impact the lung alveolarization of piglets. The probiotics could improve the lung alveolarization of preterm minipigs by promoting the development of ileum.
Animals ; Body Weight ; Female ; Humans ; Lung ; Male ; Pregnancy ; Premature Birth ; Probiotics/therapeutic use* ; Swine ; Swine, Miniature

BACKGROUND: Containing a certain proportion of mesenchymal stem cells, inflammatory dental tissue showed great tissue regeneration potential in recent years. However, whether it is applicable to promote tissue regeneration in vivo remains to be elucidated. Therefore, we evaluated the feasibility of stem cells from inflammatory dental pulp tissues (DPSCs-IPs) to reconstruct periodontal defects in miniature pigs. METHODS: The autologous pig DPSCs-IPs were first cultured, appraised and loaded onto β-tricalcium phosphate (β-TCP). The compounds were then engrafted into an artificially-created periodontal defect. Three months later, the extent of periodontal regeneration was evaluated. Clinical examination, radiological examination and immunohistochemical staining were used to assess periodontal regeneration. RESULTS: The data collectively showed that DPSCs-IPs from miniature pigs expressed moderate to high levels of STRO-1 and CD146 as well as low levels of CD34 and CD45. DPSCs-IPs have osteogentic, adipogenic and chondrogenic differentiation abilities. DPSCs-IPs were engrafted onto β-TCP and regenerated bone to repair periodontal defects by 3 months' post-surgical reconstruction. CONCLUSION: Autologous DPSCs-IPs may be a feasible means of periodontal regeneration in miniature pigs.
Dental Pulp ; Mesenchymal Stromal Cells ; Periodontitis ; Regeneration ; Stem Cells ; Swine ; Swine, Miniature

To establish a method for isolation, culture and identification of adipose-derived mesenchymal stem cells (ASCs) from the inbreed line miniature pig of Wuzhishan (ILMW).
 Methods: A total of 100 g adipose tissues were obtained from subcutaneous tissues of neck in six-month old healthy ILMW (3 samples, male). ASCs from ILMW (ILMW-ASCs) were isolated from adipose tissues through 0.1% collagenase digestion. The cells at the 3rd, 5th, 8th, 13th passages were collected. Cell morphology, size, phenotype, cell cycle, and apoptosis were monitored. Cell differentiation was induced and cell proliferation curve was drawn.
 Results: The ILMW-ASCs, fibroblast-like or whirlpool-like, began the adherence at 36 h and entered a logarithmic phase in the 5th day. Eighty percent of them were fused in the 7th day. The average diameter and volume of ILMW-ASCs were (17.00±0.54) µm and (2.58±0.24)×10-9 L, respectively. The expressions of CD29, CD44 and CD90 were positive, and there was no significant difference between the different passages (all P>0.05). The expressions of CD45, CD8a and HLA-DR were increased with the increase in passages after the 3th passage (all P<0.05). The adipogenic induction of ILMW-ASCs was observed by positive oil red O staining, and the osteogenic induction of ILMW-ASCs was determined by positive alizarin red staining. Apoptosis and senescence occurred in the 13 passage of ILMW-ASCs, and the proportion of S phase of cell cycle was lower than that in lower passages (all P<0.05). 
 Conclusion: ILMW-ASCs are one of the best choice for porcine ASCs, which might provide a source of candidate stem cells for therapy of large animal disease models and tissue or organ repairment.
Adipose Tissue ; Animals ; Cell Differentiation ; Cells, Cultured ; Male ; Mesenchymal Stem Cells ; Swine ; Swine, Miniature

OBJECTIVETo investigate the change of morphology, biomechanics and histology after osteotomy of mandibular outer cortex.

METHODSThe mandibular outer cortex that involves angle and part of body was removed at one side in 8 minitype pigs aged 8-12 months. 2 pigs were selected randomly for histologic examination 12 weeks after operation. The other 6 animals were killed 24 weeks after operation. The thickness of new-formed mandibular outer cortex was measured and compared with that of operated side. Biomechanical test was performed in bilateral angles. Histological observation was made in the operated side.

RESULTSThe thickness of outer cortex was (2.1 +/- 0.3) mm and (2.5 +/- 0.4) mm in the operated side and opposite side, respectively, showing a significant difference between them (P < 0.01). The maximum load was (401.76 +/- 204.91) N and (585.42 +/- 413.07) N in the operated side and opposite side, respectively (P > 0.05). The Rigidity was (2172.19 +/- 1174.73) N/mm and (2363.90 +/- 1547.48) N/mm (P > 0.05). There was no statistical difference in biomechanics between the two sides. The histologic study showed histologically complete regeneration of outer cortex 24 weeks after mandibular outer cortex osteotomy.

CONCLUSIONSAfter resection of mandibular outer cortex, the histologic restoration is complete, but the new-formed outer cortex is thinner with local depression. Bone tubercle can be seen at the angle after bone regeneration. There is no obvious change in biomechanics after outer cortex osteotomy.

Animals ; Biomechanical Phenomena ; Female ; Male ; Mandible ; surgery ; Osteotomy ; methods ; Swine ; Swine, Miniature

BACKGROUNDMiniature pig (minipig) is increasingly used as a large animal model for a variety of biomedical studies. Little information is available in the literature on anatomy, histology and sialograghy of the submandibular gland of the minipig. The purpose of this study was to characterize the morphology of a miniature pig's (minipig) submandibular gland as a large animal model for further biomedical studies.

METHODSFive minipigs were subjected to sialographic, anatomic, histologic, histochemical and ultrastructural evaluations for submandibular glands.

RESULTSSialograms showed a long, horizontal main excretory duct and a pear-shaped gland located inferoposterior to the angle of the mandible. The submandibular glands lied superficial to the suprahyoid, and infrahyoid muscle groups, and were covered by the inferior portion of the parotid gland. The submandibular glands were characterized by a mixed parenchyma of mucous and serous secretory acini. Alcian blue (AB) staining and periodic acid-Schiff (PAS) reactions demonstrated that minipig submandibular glands synthesized and secreted acid mucous substances by serous cells and polysaccharide, and neutral mucous substances, by mucous cells.

CONCLUSIONThe submandibular gland of the minipig is considered a useful large salivary gland animal model for biomedical studies.

Animals ; Female ; Histocytochemistry ; Submandibular Gland ; chemistry ; cytology ; physiology ; ultrastructure ; Swine ; Swine, Miniature ; anatomy & histology