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Elof Eriksson - One of the best experts on this subject based on the ideXlab platform.
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modulation of scarring in a liquid environment in the Yorkshire Pig
Wound Repair and Regeneration, 2009Co-Authors: Richard G Reish, Baraa Zuhaili, Juri Bergmann, Pejman Aflaki, Taro Koyama, Florian Hackl, Emily Waisbren, Jose A Canseco, Kapil Verma, Elof ErikssonAbstract:ABSTRACT Decreased inflammatory response seen in wet wound healing may be correlated with diminished scarring. This study seeks to test this hypothesis and to validate a model of scarring in the Yorkshire Pig. Four Yorkshire Pigs were used to create 36 dorsal wounds per Pig (144 wounds total) in the following groups: full-thickness excisional, partial thickness, meshed split-thickness skin grafts, sheet split-thickness skin grafts, minced skin, and incisional wounds. Wounds were randomized into wet and dry groups. Wet wounds were enclosed in polyurethane chambers with 2 mL of normal saline. Dry wounds were covered with regular gauze. Terminal biopsies were performed at 72 hours and day 28. Histology demonstrated significantly less inflammatory infiltrate, thicker neoepidermis, more pronounced rete ridge formation, and decreased scar tissue thickness in wet wounds. The mean macroscopic scar surface area was significantly decreased in full-thickness excisional wet wounds compared with dry wounds (61.2 mm(2) vs. 150.8 mm(2), p<0.01). Hydroxyproline content was decreased in full-thickness wet compared with dry groups (44.81 vs. 62.21 mg/g, p<0.01). Tensile strength was 90% greater in full-thickness wet compared with dry groups (p<0.01). Healing in the liquid environment significantly reduced scar formation. This model will allow for future investigation of high-concentration topical scar-modulating agents in the liquid environment.
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modulation of cutaneous scarring in a liquid environment in the Yorkshire Pig
Journal of The American College of Surgeons, 2008Co-Authors: Richard G Reish, Baraa Zuhaili, Juri Bergmann, Pejman Aflaki, Taro Koyama, Emily Waisbren, Feng Yao, Elof ErikssonAbstract:ETHODS: Three Yorkshire Pigs were used to create 36 dorsal ounds per Pig (108 wounds total) in the following groups: full hickness excisional, partial thickness, meshed STSG, sheet STSG, inced skin, and incisional wounds. Wounds were randomized into et and dry groups. Wet wounds were enclosed in polyurethane hambers with 2 ml of normal saline. Dry wounds were covered with egular gauze. All wounds were converted to dry healing after two eeks. On day 28, terminal biopsies were performed.
Nicole S Gibran - One of the best experts on this subject based on the ideXlab platform.
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Dermal Fibroblasts from the Red Duroc Pig Have an Inherently Fibrogenic Phenotype: An In Vitro Model of Fibroproliferative Scarring.
Plastic and reconstructive surgery, 2015Co-Authors: Ravi F. Sood, Lara A Muffley, Max Seaton, Pornthep Sirimahachaiyakul, Anne M. Hocking, Nicole S GibranAbstract:BACKGROUND The pathophysiology of hypertrophic scarring is unknown in part because of the lack of a robust animal model. Although the red Duroc Pig has emerged as a promising in vivo model, the cellular mechanisms underlying Duroc scarring are unknown, and the size and cost of Duroc Pigs are obstacles to their use. Given the central role of the dermal fibroblast in scarring, the authors hypothesized that dermal fibroblasts from the Duroc Pig exhibit intrinsic differences in key aspects of the fibroblast response to injury compared with those from the Yorkshire Pig, a same-species control that heals normally. METHODS Duroc and Yorkshire dermal fibroblasts were isolated from uninjured dorsal skin. Actin stress fibers and focal adhesions were visualized by immunocytochemistry and transmission electron microscopy. Cell migration was measured using a scratch wound-closure assay. Contractile function was assessed by collagen gel contraction. Expression of scarring-related genes was determined by quantitative real-time reverse-transcriptase polymerase chain reaction, and transforming growth factor (TGF)-β1 protein expression was determined by Western blotting. RESULTS Duroc dermal fibroblasts display increased adhesion-complex formation, impaired migration, enhanced collagen contraction, and profibrotic gene and protein expression profiles compared with Yorkshire fibroblasts at baseline. In addition, Duroc fibroblasts overexpressed TGF-β1 and were less responsive to exogenous TGF-β1. CONCLUSIONS Duroc dermal fibroblasts have inherent myofibroblastic differentiation that may account for the pathologic scarring in these animals. The authors' data further validate the Duroc model and support Duroc fibroblast cell culture as a simple, inexpensive, reproducible, and biologically tractable in vitro model for the study of fibroproliferative scarring.
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review of the female duroc Yorkshire Pig model of human fibroproliferative scarring
Wound Repair and Regeneration, 2007Co-Authors: Kathy Q Zhu, Frank F Isik, Nicole S Gibran, G J Carrougher, Loren H EngravAbstract:Hypertrophic scarring after burns is an unsolved problem and remains as devastating today as it was in the 40s and it may be that the main reason for this is the lack of an accepted, useful animal model. The female, red Duroc Pig was described as a model of hypertrophic scarring nearly 30 years ago but then vanished from the literature. This seemed strange since the authors reported that 12 of 12 Pigs developed thick scar. In the mid 90s we explored the model and found that, indeed, the red Duroc Pig does make thick scar. Other authors have established that the Yorkshire Pig does not heal in this fashion so there is the possibility of a same species control. We have continued to explore the Duroc/Yorkshire model and herein describe our experiences. Is it a perfect model of hypertrophic scarring? No. Is it a useful model of hypertrophic scarring? Time will tell. We have now obtained gene expression data from the Duroc/Yorkshire model and analysis is underway.
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The microvasculature in cutaneous wound healing in the female red Duroc Pig is similar to that in human hypertrophic scars and different from that in the female Yorkshire Pig.
Journal of burn care & research : official publication of the American Burn Association, 2007Co-Authors: Youfu Xie, Nicole S Gibran, G J Carrougher, Kathy Q Zhu, Heike Deubner, Dominic A. Emerson, Loren H EngravAbstract:The female red Duroc Pig has been found to be a promising model of hypertrophic scarring. The female Yorkshire Pig has been demonstrated to heal in a very different manner, more resembling human normotrophic scarring. Given these observations, we studied microvessel density, an important aspect of wound healing, in human hypertrophic scars and the scars of the female Duroc and Yorkshire Pigs. We studied microvessel density in uninjured skin; hypertrophic scars at 6 months or less, 7 to 12, and longer than 12 months; female Duroc tissues at 3 weeks and 3 and 5 months; and similar Yorkshire tissue, including uninjured skin and shallow and deep wounds. Antifactor VIII-related antigen was used to mark the endothelial cells. Computed assessment of microvessel density was used to quantify the microvasculature. In human hypertrophic scars, the microvessels were increased dramatically, and microvessel density and area were significantly elevated. We found similar results in the Duroc tissues at 5 months after deep wounding. In contrast, we found far less microvasculature and, at 5 months, the values had returned to normal in the Yorkshire tissues. This quantitative study of microvessel density further validates the female Duroc Pig as an animal model of hypertrophic scarring and the female Yorkshire Pig as a control.
Loren H Engrav - One of the best experts on this subject based on the ideXlab platform.
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review of the female duroc Yorkshire Pig model of human fibroproliferative scarring
Wound Repair and Regeneration, 2007Co-Authors: Kathy Q Zhu, Frank F Isik, Nicole S Gibran, G J Carrougher, Loren H EngravAbstract:Hypertrophic scarring after burns is an unsolved problem and remains as devastating today as it was in the 40s and it may be that the main reason for this is the lack of an accepted, useful animal model. The female, red Duroc Pig was described as a model of hypertrophic scarring nearly 30 years ago but then vanished from the literature. This seemed strange since the authors reported that 12 of 12 Pigs developed thick scar. In the mid 90s we explored the model and found that, indeed, the red Duroc Pig does make thick scar. Other authors have established that the Yorkshire Pig does not heal in this fashion so there is the possibility of a same species control. We have continued to explore the Duroc/Yorkshire model and herein describe our experiences. Is it a perfect model of hypertrophic scarring? No. Is it a useful model of hypertrophic scarring? Time will tell. We have now obtained gene expression data from the Duroc/Yorkshire model and analysis is underway.
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The microvasculature in cutaneous wound healing in the female red Duroc Pig is similar to that in human hypertrophic scars and different from that in the female Yorkshire Pig.
Journal of burn care & research : official publication of the American Burn Association, 2007Co-Authors: Youfu Xie, Nicole S Gibran, G J Carrougher, Kathy Q Zhu, Heike Deubner, Dominic A. Emerson, Loren H EngravAbstract:The female red Duroc Pig has been found to be a promising model of hypertrophic scarring. The female Yorkshire Pig has been demonstrated to heal in a very different manner, more resembling human normotrophic scarring. Given these observations, we studied microvessel density, an important aspect of wound healing, in human hypertrophic scars and the scars of the female Duroc and Yorkshire Pigs. We studied microvessel density in uninjured skin; hypertrophic scars at 6 months or less, 7 to 12, and longer than 12 months; female Duroc tissues at 3 weeks and 3 and 5 months; and similar Yorkshire tissue, including uninjured skin and shallow and deep wounds. Antifactor VIII-related antigen was used to mark the endothelial cells. Computed assessment of microvessel density was used to quantify the microvasculature. In human hypertrophic scars, the microvessels were increased dramatically, and microvessel density and area were significantly elevated. We found similar results in the Duroc tissues at 5 months after deep wounding. In contrast, we found far less microvasculature and, at 5 months, the values had returned to normal in the Yorkshire tissues. This quantitative study of microvessel density further validates the female Duroc Pig as an animal model of hypertrophic scarring and the female Yorkshire Pig as a control.
Tomoyuki Shibahara - One of the best experts on this subject based on the ideXlab platform.
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systemic streptococcus dysgalactiae subspecies equisimilis infection in a Yorkshire Pig with severe disseminated suppurative meningoencephalomyelitis
Journal of Veterinary Medical Science, 2014Co-Authors: Kazufumi Kasuya, Eiji Yoshida, Rieko Harada, Mio Hasegawa, Hiroyuki Osaka, Masaharu Kato, Tomoyuki ShibaharaAbstract:An 18-week-old female breeding Yorkshire Pig displayed symptoms of astasia and subsequently died. Histologically, severe disseminated suppurative meningoencephalomyelitis was detected, as were numerous myocardial microabscesses. Gram-positive cocci were detected in these suppurative lesions, and these cocci reacted with an antibody against Streptococcus C group species. Gram-positive cocci were isolated from the liver, spleen, kidney, heart, lungs, pleural abscess and articular fluid of the right tarsal joint. The isolates were β-hemolytic, categorized into Lancefield group C and were identified as Streptococcus dysgalactiae subspecies equisimilis by analysis of the 16S ribosomal DNA sequence. This is the first report of systemic S. equisimilis infection in a Pig with severe disseminated suppurative meningoencephalomyelitis.
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NOTE Pathology Systemic Streptococcus dysgalactiae Subspecies equisimilis Infection in a Yorkshire Pig with Severe Disseminated Suppurative Meningoencephalomyelitis
2013Co-Authors: Kazufumi Kasuya, Eiji Yoshida, Rieko Harada, Mio Hasegawa, Hiroyuki Osaka, Masaharu Kato, Tomoyuki ShibaharaAbstract:ABSTRACT. An 18-week-old female breeding Yorkshire Pig displayed symptoms of astasia and subsequently died. Histologically, severe disseminated suppurative meningoencephalomyelitis was detected, as were numerous myocardial microabscesses. Gram-positive cocci were detected in these suppurative lesions, and these cocci reacted with an antibody against Streptococcus C group species. Gram-positive cocci were isolated from the liver, spleen, kidney, heart, lungs, pleural abscess and articular fluid of the right tarsal joint. The isolates were β-hemolytic, categorized into Lancefield group C and were identified as Streptococcus dysgalactiae subspecies equisimilis by analysis of the 16S ribosomal DNA sequence. This is the first report of systemic S. equisimilis infection in a Pig with severe disseminated suppurative meningoencephalomyelitis. KEY WORDS: Streptococcus dysgalactiae subspecies equisimilis, swine, systemic infection. doi: 10.1292/jvms.13-0526; J. Vet. Med. Sci. 76(5): 715–718, 2014 Swine streptococcosis is an important infectious dis-ease caused by Streptococcus species. Streptococcus suis, Streptococcus dysgalactiae and Streptococcus porcinus are indigenous bacteria isolated from the tonsils, intestinal tracts and genital organs of clinically healthy Pigs. However, they are also opportunistic pathogens capable of causing swin
Stephen P. Ford - One of the best experts on this subject based on the ideXlab platform.
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conceptus competition for uterine space different strategies exhibited by the meishan and Yorkshire Pig
Journal of Animal Science, 2002Co-Authors: Kimberly A Vonnahme, M E Wilson, Stephen P. FordAbstract:Our laboratory has demonstrated that Yorkshire placentae increase in size and surface area during the final third of gestation. In contrast, Meishan placental size remains constant during late gestation, but the density of blood vessels at the placental-endometrial interface increases markedly. Preliminary observations from our laboratory suggest that if one of two adjacent Meishan fetuses dies, the placenta of the remaining Meishan conceptus fails to increase its length of implantation or its placental weight or surface area. In contrast, if one of two adjacent Yorkshire fetuses dies, the adjacent conceptus accelerates its placental growth. The objective of this experiment was to document that Yorkshire, but not Meishan, conceptuses accelerate placental growth when adjacent fetuses are experimentally destroyed on d 40 of gestation. Straightbred Meishan (n = 5) and Yorkshire (n = 5) females were laparotomized and one uterine horn was randomly assigned to receive fetal crushing (treated horn); the other uterine horn served as a within-animal control. In the treated horn, every other fetus was then crushed through the uterine wall and the animals were allowed to recover. On d 111, animals were killed, uteri were recovered, and fetal weight, crown-rump length (CRL), placental weight, implantation site length, and placental surface area were recorded. Although there were no statistically significant differences in fetal weight or CRL observed between treated or control horns of females of either breed, there was a tendency for the fetuses in the treated uterine horn to be longer and heavier in both breeds. There were no differences in placental weight, placental surface area, or implantation site length between conceptuses in Meishan treated and control horns, which averaged 173.8+/-6.4 g, 1,162.7+/-35.9 cm2, and 19.0+/-0.4 cm, respectively. In contrast, placental weight, placental surface area, and implantation site length were increased (P < 0.05) in Yorkshire treated horns compared to Yorkshire control horns (306.1+/-26.0 g, 1,835+/-93.9 cm2, and 33.4+/-1.5 cm vs 253.7+/-13.4 g, 1,474.3+/-50.4 cm2, and 27.2+/-0.8 cm; respectively). These data confirm that Yorkshire conceptuses, but not Meishan conceptuses, accelerate placental growth when adjacent littermates perish as late as d 40 of gestation. These data indicate that differences exist in the strategies employed by Meishan and Yorkshire conceptuses in the competition for nutrients during gestation.
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conceptus competition for nutrients in the porcine uterus different strategies exhibited by the meishan and Yorkshire Pig breeds
2001Co-Authors: Kimberly A Vonnahme, Stephen P. FordAbstract:and Implications Previous research from our laboratory demonstrated that Meishan conceptuses develop more slowly and synchronously to day 30 of gestation than conceptuses of U.S. Pig breeds. Furthermore, the reduced size of the Meishan conceptus on day 30 allows more Meishan than Yorkshire conceptuses to occupy the same amount of limited uterine space. As a result, Meishan litter size is significantly larger than that of U.S. Pig breeds (13−14 vs. 9-10 Piglets/litter). An additional consistent, but unexpected, finding in the Meishan Pig was the observation that there was significantly greater amounts of unoccupied uterine space in the Meishan than the Yorkshire female at term. We previously demonstrated that an additional strategy of the Meishan female to increase fecundity was to super-vascularize its placental membranes so that oxygen and nutrient transfer from the sow could be accomplished over a reduced surface area, negating the necessity of further placental growth. These data suggested that when a Meishan conceptus dies, the placenta of its neighbors need not grow into this newly vacated space, whereas the Yorkshire conceptus might increase the size of its less vascular placenta to use the opportunity. Therefore, it was our objective to confirm that Yorkshire conceptuses, but not Meishan conceptuses increase their placental size when adjacent conceptuses are experimentally destroyed on day 40 of gestation. To accomplish this objective, pregnant Meishan and Yorkshire females were laporatomized on day 40. One uterine horn was randomly chosen to be receive alternative fetal crushing (i.e., every other fetus in the horn was crushed by mechanical pressure), whereas the other uterine horn served as the control horn. At slaughter on day 111 of gestation (term = 114 days), we found no differences in fetal weight between the control and treated horns regardless of breed. Similarly, there was no difference in placental weight or surface area or implantation site length (the length of placental attachment in the uterine horn) between the control and treated horns in the Meishan. In contrast, however, there was a marked increase in placental weight and surface area, as well as implantation site length for conceptuses in the treated horn of the Yorkshire gilts versus the control horn. Furthermore, the unoccupied spaces between Meishan conceptuses in the treated horn were 2-fold greater than for conceptuses in the control horn, whereas there were no differences in the length of unoccupied spaces between conceptuses in the Yorkshire’s control or treated horns. These data suggest that in the Meishan treated horn, conceptuses do not use this extra space as effectively as conceptuses in the Yorkshire treated horn. The inability of Meishan placenta to grow into adjacent unoccupied spaces may not be detrimental to conceptus survival due to its greater ability to increase vascular density in response to increasing fetal demands. If U.S. Pig breeds have the potential to increase placental vascularity, rather than increase in placental size to nourish the growing fetuses, the potential exists for increasing litter size due to a decrease in uterine competition throughout gestation.
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a comparison of the number of inner cell mass and trophectoderm cells of preimplantation meishan and Yorkshire Pig embryos at similar developmental stages
Reproduction, 1996Co-Authors: Rocio Melissa Rivera, Curtis R Youngs, Stephen P. FordAbstract:Day 12 blastocysts from Meishan gilts contain fewer cells than do day 12 blastocysts from Yorkshire gilts. The purpose of this study was to evaluate the effect of breed on the relative numbers of inner cell mass and trophectoderm cells in Meishan and Yorkshire embryos at similar stages. Embryos were collected on days 5.5-6.5 of gestation and were subjected to image analysis and differential cell staining. No breed differences were detected in the thickness of zona pellucida or in the areas of the perivitelline space, embryo proper, blastocoel and inner cell mass at any of the developmental stages examined (compact morula, early blastocyst or blastocyst). However, differences were observed in the pattern of growth of embryos from Meishan versus Yorkshire gilts. The total number of cells of Meishan embryos from Meishan gilts increased progressively from the compact morula through the blastocyst stage, whereas the total number of cells of embryos from Yorkshire gilts remained constant from compact morula through to early blastocyst, and then increased markedly from the early blastocyst to the blastocyst stage. At the blastocyst stage, Meishan embryos contained fewer (P < 0.05) cells than did Yorkshire embryos, and this lower number of cells was due entirely to fewer (P < 0.05) trophectoderm cells. As the number of inner cell mass cells increased during embryonic growth, Meishan embryos exhibited a slower (P < 0.02) increase in the number of trophectoderm cells than did Yorkshire embryos. These results demonstrate that the reduced number of cells present in Meishan embryos results from a selective reduction in the number of trophectoderm, but not inner cell mass, cells.
