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2.
Forensic Sci Int Genet ; 44: 102160, 2020 01.
Article in English | MEDLINE | ID: mdl-31683165

ABSTRACT

In October 2018, Colorado Parks and Wildlife seized an animal believed to be an illegally possessed bobcat. The owner claimed the animal was a bobcat/domestic cat hybrid, exempted from license requirements. Burden of proof lay with CPW to determine the lineage of the animal. Commercial microsatellite arrays and DNA barcoding have not been developed for identification of bobcat/domestic cat hybrids, and limited time and resources prevented development of such tests for this application. Instead, we targeted endogenous feline leukemia virus (enFeLV) to quickly and inexpensively demonstrate the absence of domestic cat DNA in the contested animal. Using this assay, we were able to confirm that the contested animal lacked enFeLV, and therefore was not a domestic cat hybrid.


Subject(s)
Animals, Domestic/genetics , Animals, Wild/genetics , Cat Diseases/virology , Endogenous Retroviruses/genetics , Hybridization, Genetic , Leukemia Virus, Feline/genetics , Animals , Cat Diseases/genetics , Cats , Polymerase Chain Reaction
3.
Osteoarthritis Cartilage ; 26(6): 711-729, 2018 06.
Article in English | MEDLINE | ID: mdl-29544858

ABSTRACT

OBJECTIVE: Osteoarthritis (OA) is a leading cause of disability in the world. Mesenchymal stem cells (MSCs) have been studied to treat OA. This review was performed to systematically assess the quality of literature and compare the procedural specifics surrounding MSC therapy for osteoarthritis. DESIGN: PubMed, CINAHL, EMBASE and Cochrane Central Register of Controlled Trials were searched for studies using MSCs for OA treatment (final search December 2017). Outcomes of interest included study evidence level, patient demographics, MSC protocol, treatment results and adverse events. Level I and II evidence articles were further analyzed. RESULTS: Sixty-one of 3,172 articles were identified. These studies treated 2,390 patients with osteoarthritis. Most used adipose-derived stem cells (ADSCs) (n = 29) or bone marrow-derived stem cells (BMSCs) (n = 30) though the preparation varied within group. 57% of the sixty-one studies were level IV evidence, leaving five level I and nine level II studies containing 288 patients to be further analyzed. Eight studies used BMSCs, five ADSCs and one peripheral blood stem cells (PBSCs). The risk of bias in these studies showed five level I studies at low risk with seven level II at moderate and two at high risk. CONCLUSION: While studies support the notion that MSC therapy has a positive effect on OA patients, there is limited high quality evidence and long-term follow-up. The present study summarizes the specifics of high level evidence studies and identifies a lack of consistency, including a diversity of MSC preparations, and thus a lack of reproducibility amongst these articles' methods.


Subject(s)
Osteoarthritis/surgery , Stem Cell Transplantation , Humans , Stem Cell Transplantation/methods , Treatment Outcome
5.
J Vasc Surg ; 34(6): 1111-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11743569

ABSTRACT

The production of matrix metalloproteinases (MMPs), such as MMP9, by macrophages may be a critical factor in the rupture of unstable atherosclerotic plaques and aortic aneurysms. Therefore, we studied the role of matrix and soluble cytokines in the regulation of monocyte/macrophage expression of MMP9. Although freshly isolated monocytes synthesize little MMP9, cells cultured on tissue-culture plastic differentiate into macrophages and synthesize maximal amounts of MMP9. Differentiated macrophages cultured on plastic are unresponsive to further stimulation by interleukin 1beta, tumor necrosis factor alpha, or platelet-derived growth factor BB. In contrast, monocytes cultured on polymerized collagen synthesize much less MMP9 than cells cultured on plastic and demonstrate a more than three-fold increase in MMP9 synthesis in response to interleukin 1beta, tumor necrosis factor alpha, and platelet-derived growth factor BB. To determine whether the physical state of the collagen was critical for the decrease in basal synthesis of MMP9, monocytes were cultured in suspension for 5 days to allow differentiation and then seeded onto monomer or polymerized collagen. Synthesis of MMP9 was significantly decreased in cells on polymerized collagen and modestly increased in macrophages seeded on monomer collagen. These results suggest that MMP9 synthesis by macrophages in the vessel wall may be under negative control by native, polymerized collagen and that disruption of this native conformation could increase MMP9 production. In addition, cells in contact with the collagen matrix are potentially more responsive to soluble mediators such as platelet-derived growth factor, interleukin 1beta, and tumor necrosis factor alpha.


Subject(s)
Cell Culture Techniques/methods , Culture Media/pharmacology , Macrophages/enzymology , Matrix Metalloproteinase 9/biosynthesis , Monocytes/enzymology , Polymers/pharmacology , Aortic Aneurysm/enzymology , Arteriosclerosis/enzymology , Cell Culture Techniques/standards , Cell Differentiation/physiology , Cell Size , Collagen Type I/pharmacology , Cytokines/physiology , Extracellular Space/physiology , Growth Substances/physiology , Humans , Immunohistochemistry , Macrophages/drug effects , Monocytes/drug effects , Precipitin Tests , Tumor Necrosis Factor-alpha/pharmacology
6.
J Biol Chem ; 276(23): 20130-5, 2001 Jun 08.
Article in English | MEDLINE | ID: mdl-11274221

ABSTRACT

The epidermal growth factor receptor (EGFR) and the non-receptor protein tyrosine kinases Src and Pyk2 have been implicated in linking a variety of G-protein-coupled receptors (GPCR) to the mitogen-activated protein (MAP) kinase signaling cascade. In this report we apply a genetic strategy using cells isolated from Src-, Pyk2-, or EGFR-deficient mice to explore the roles played by these protein tyrosine kinases in GPCR-induced activation of EGFR, Pyk2, and MAP kinase. We show that Src kinases are critical for activation of Pyk2 in response to GPCR-stimulation and that Pyk2 and Src are essential for GPCR-induced tyrosine phosphorylation of EGFR. By contrast, Pyk2, Src, and EGFR are dispensable for GPCR-induced activation of MAP kinase. Moreover, GPCR-induced MAP kinase activation is normal in fibroblasts deficient in both Src and Pyk2 (Src-/-Pyk2-/- cells) as well as in fibroblasts deficient in all three Src kinases expressed in these cells (Src-/-Yes-/-Fyn-/- cells). Finally, experiments are presented demonstrating that, upon stimulation of GPCR, activated Pyk2 forms a complex with Src, which in turn phosphorylates EGFR directly. These experiments reveal a role for Src kinases in Pyk2 activation and a role for Pyk2 and Src in tyrosine phosphorylation of EGFR following GPCR stimulation. In addition, EGFR, Src family kinases, and Pyk2 are not required for linking GPCRs with the MAP kinase signaling cascade.


Subject(s)
ErbB Receptors/metabolism , GTP-Binding Proteins/metabolism , MAP Kinase Signaling System , Protein-Tyrosine Kinases/metabolism , src-Family Kinases/metabolism , Animals , Epidermal Growth Factor/metabolism , Focal Adhesion Kinase 2 , Kinetics , Lysophospholipids/pharmacology , Mice , Signal Transduction
8.
Ann Surg ; 213(4): 292-6, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2009010

ABSTRACT

Midgestation fetal wound healing is characterized by healing without fibrosis or scar formation. The mechanisms that underlie this remarkable process are mediated in part through a fetal wound extracellular matrix rich in hyaluronic acid. In this study a newly developed assay was used to determine the hyaluronic acid levels in fetal and adult wound fluid. Adult wound fluid had a rapid increase in hyaluronic acid, which peaked at 3 days and decreased to 0 by 7 days. In contrast levels of hyaluronic acid in fetal wound fluid increased rapidly and remained significantly elevated for 3 weeks. This prolonged presence of hyaluronic acid in the matrix of fetal wounds creates a 'permissive' wound environment that promotes fetal fibroblast movement and proliferation and inhibits cytodifferentiation. Such a matrix environment promotes healing by regeneration rather than by scarring. This observation has therapeutic implications. The prolonged application of hyaluronic acid or hyaluronate protein complexes to wounds in children or adults may modulate healing in a manner that makes the wounds more fetal-like.


Subject(s)
Body Fluids/chemistry , Fetus/physiology , Hyaluronic Acid/analysis , Wound Healing , Animals , Extracellular Matrix/chemistry , Female , Fetus/surgery , Models, Biological , Pregnancy , Sheep , Time Factors
9.
Article in English | MEDLINE | ID: mdl-2035257

ABSTRACT

Cardiac myxoma is the most common primary tumor of the heart. This tumor has a gelatinous stroma that is thought to be composed of glycosaminoglycans, the classical acid mucopolysaccharide ground substance. We examined both biochemically and histologically the hyaluronic acid in a case of cardiac myxoma using a newly developed hyaluronic acid-binding protein probe. We observed that hyaluronic acid was localized in the amorphous stroma and occurred at levels 30 times that found in normal atrial septum.


Subject(s)
Heart Neoplasms/chemistry , Hyaluronic Acid/analysis , Myxoma/chemistry , Humans , Male , Middle Aged
10.
Ann Surg ; 210(5): 667-72, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2818035

ABSTRACT

Recent clinical and experimental evidence suggests that the fetus responds to injury in a fashion fundamentally different from that of the adult. Our initial experience with human open fetal surgery reinforces experimental observations that the fetal wounds heal without the scarring, inflammation, and contraction that often accompany adult wounds. In this study we examine fetal wound fluid in an attempt to elucidate the control mechanisms that endow the fetus with unique healing properties. The extracellular matrix of fetal wounds is rich in hyaluronic acid, a glycosaminoglycan found in high concentrations whenever there is tissue proliferation, regeneration, and repair. We establish that wound fluid from the fetus contains high levels of hyaluronic acid-stimulating activity that may underlie the elevated deposition of hyaluronic acid in the fetal wound matrix. In contrast there was no hyaluronic acid-stimulating activity present in adult wound fluid. Hyaluronic acid, in turn, fosters an extracellular environment permissive for cell motility and proliferation that may account for the unique properties observed in fetal wound healing.


Subject(s)
Exudates and Transudates/physiology , Fetus/surgery , Hyaluronic Acid/biosynthesis , Wound Healing , Age Factors , Animals , Fetus/metabolism , Fetus/physiology , Fibrosarcoma/metabolism , Fibrosarcoma/pathology , Mitosis , Rats , Sheep , Tumor Cells, Cultured/metabolism , Tumor Cells, Cultured/pathology , Wound Healing/physiology
11.
Cancer Res ; 49(13): 3499-505, 1989 Jul 01.
Article in English | MEDLINE | ID: mdl-2731171

ABSTRACT

The sine qua non of malignancy is the ability of tumor cells to migrate and invade surrounding tissue. There are many substances that have been described that enhance cell motility and hyaluronic acid is prominent among these. Hyaluronic acid is a high molecular weight alternating disaccharide polymer found in abundance in extracellular matrices whenever rapid cell proliferation or tissue regeneration and repair occur. It creates a permissive environment for cell motility during embryogenesis, and high levels of hyaluronic acid also correlate with increased tumor cell invasion and aggressiveness. Little is known about the regulation of hyaluronic acid production, either in normal tissue or in malignancy. In this study, we characterize a hyaluronic acid-stimulating activity in fetal calf serum and describe a similar activity in the sera of breast cancer patients. The stimulating activity was measured by placing aliquots of test substance on fibrosarcoma cells. These indicator cells, which synthesize copious quantities of hyaluronic acid, respond to stimulation in a time- and dose-dependent fashion. The fetal calf serum hyaluronic acid-stimulating activity is maximum early in gestation and then falls rapidly to essentially no activity at term. This activity was partially purified from 120-day fetal calf serum by concanavalin A-Sepharose affinity and ion exchange chromatography and is accounted for by a glycoprotein with a molecular weight of 150,000 on gel filtration under native conditions. The sera of breast cancer patients with measurable burden of disease also contained hyaluronic acid-stimulating activity, which was not present in normal serum donors or in breast cancer patients without evidence of disease. The production of this stimulating activity may contribute to the development of the malignant phenotype by inducing hyaluronic acid-rich microenvironments that are permissive to tumor cell invasion and metastases.


Subject(s)
Breast Neoplasms/blood , Fetal Blood/physiology , Hyaluronic Acid/biosynthesis , Animals , Cattle , Cells, Cultured , Humans , In Vitro Techniques , Neoplasm Metastasis , Rats , Sarcoma, Experimental/metabolism
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