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61.
Chiara Gomiero Giulia Bertolutti Tiziana Martinello Nathalie Van Bruaene Sarah Y. Broeckx Marco Patruno Jan H. Spaas 《Veterinary research communications》2016,40(1):39-48
Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate. 相似文献
62.
63.
Galina P. Simeonova Svetozar Z. Krastev Radostin S. Simeonov 《Veterinary research communications》2016,40(3-4):107-115
Background
The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined and many variations between experimental animal models and spontaneous disease exist.Objectives
The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings.Methods
Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation.Results
CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction.Conclusions
Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans.64.
65.
Licht BG Lin S Luo Y Hyson LL Licht MH Harper KM Sullivan SA Fernandez SA Johnston EV 《Journal of the American Veterinary Medical Association》2007,231(10):1520-1528
OBJECTIVE: To determine clinical characteristics and mode of inheritance of seizures in a family of Standard Poodles. DESIGN: Case series. ANIMALS: 90 Standard Poodles descended from the same maternal bloodline (30 with probable idiopathic epilepsy [PIE] and 60 without any history of seizures). PROCEDURES: Researchers contacted owners to determine whether dogs had ever had any seizures and, if so, the nature of any such seizures and any potential underlying causes. Dogs were considered to have PIE if they were between 6 months and 7.5 years old at the time of seizure onset and had no evidence of any underlying cause. To determine the mode of inheritance, segregation analyses were designed to allow the family to be analyzed as a whole, as opposed to as nuclear families. Competing models of inheritance were compared statistically for their ability to explain the data. RESULTS: Of the dogs with PIE, 28 (93%) had focal onset seizures with or without secondary generalization. Median age of onset was 3.7 years; 6 dogs were > 5 years old at the onset of seizures. Segregation analyses strongly suggested that PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in this family of Standard Poodles, PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. Seizures often had focal, as opposed to generalized, onsets, and it was not uncommon for seizures to begin after 5 years of age. 相似文献
66.
Buchholz J Wergin M Walt H Gräfe S Bley CR Kaser-Hotz B 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):770-775
BACKGROUND: Squamous cell carcinomas are common skin tumors in cats. We investigated photodynamic therapy (PDT) using a new liposomal photosensitizer as a minimally invasive, effective treatment that can be easily performed while achieving good cosmetic results. AIM: The goal of this study was to assess and describe possible toxicities using a liposomal formulation of the photosensitizer meta-(Tetrahydroxyphenyl)Chlorin (m-THPC) and investigate if favorable pharmacokinetics translate into favorable tumor response and control. ANIMALS: Eighteen client-owned cats with 20 spontaneous cutaneous squamous cell carcinomas were included in the study. METHODS: PDT was performed using a new, liposomal formulation of the photosensitizer. Toxicity, tumor response, and tumor control were evaluated retrospectively. RESULTS: No general adverse effects were observed in cats treated with the new liposomal formulation. Mild local toxicity such as erythema and edema were seen in 15% of the patients. All cats responded to therapy, with a complete response rate of 100%. The overall 1-year control rate was 75%. The tumor recurrence rate was 20% with a median time to recurrence of 172.25 +/-87.1) days. CONCLUSIONS AND CLINICAL IMPORTANCE: A new liposomal photosensitizer was successfully used for squamous cell carcinoma in cats and was well tolerated. There were no systemic adverse effects observed with the liposomal formulation. The favorable pharmacokinetics of the liposomal drug resulted in a favorable tumor response. 相似文献
67.
Diniz PP Maggi RG Schwartz DS Cadenas MB Bradley JM Hegarty B Breitschwerdt EB 《Veterinary research》2007,38(5):697-710
The purpose of this study was to determine the serological and molecular prevalence of Bartonella spp. infection in a sick dog population from Brazil. At the S?o Paulo State University Veterinary Teaching Hospital in Botucatu, 198 consecutive dogs with clinicopathological abnormalities consistent with tick-borne infections were sampled. Antibodies to Bartonella henselae and Bartonella vinsonii subsp. berkhoffii were detected in 2.0% (4/197) and 1.5% (3/197) of the dogs, respectively. Using 16S-23S rRNA intergenic transcribed spacer (ITS) primers, Bartonella DNA was amplified from only 1/198 blood samples. Bartonella seroreactive and/or PCR positive blood samples (n=8) were inoculated into a liquid pre-enrichment growth medium (BAPGM) and subsequently sub-inoculated onto BAPGM/blood-agar plates. PCR targeting the ITS region, pap31 and rpoB genes amplified B. henselae from the blood and/or isolates of the PCR positive dog (ITS: DQ346666; pap31 gene: DQ351240; rpoB: EF196806). B. henselae and B. vinsonii subsp. berkhoffii (pap31: DQ906160; rpoB: EF196805) co-infection was found in one of the B. vinsonii subsp. berkhoffii seroreactive dogs. We conclude that dogs in this study population were infrequently exposed to or infected with a Bartonella species. The B. henselae and B. vinsonii subsp. berkhoffii strains identified in this study are genetically similar to strains isolated from septicemic cats, dogs, coyotes and human beings from other parts of the world. To our knowledge, these isolates provide the first Brazilian DNA sequences from these Bartonella species and the first evidence of Bartonella co-infection in dogs. 相似文献
68.
Maria Caridad Montalvo Villalba Chantal J. Snoeck Licel de los Angeles Rodriguez Lay Aurélie Sausy Dayesi Hernández López Marite Bello Corredor Barbara Marrero Sanchéz Judith M. Hübschen 《Zoonoses and public health》2023,70(1):58-68
Surveillance of hepatitis E virus (HEV) in risk groups is an important strategy to monitor its circulation pattern and to timely detect changes thereof. The aims of this cross-sectional study were to estimate the prevalence of HEV infections in pigs and humans from different regions of the country, to identify risk factors for increasing anti-HEV IgG prevalence and to characterize HEV strains. The presence of anti-HEV antibodies was assessed by commercial ELISA in serum samples from the general population, farm and slaughterhouse employees, as well as pigs sampled in the three regions of Cuba from February to September 2016. Overall, individuals with occupational exposure to swine or swine products (70/248, 28.2%) were 4 times more likely to be seropositive compared to the general population (25/285, 8.7%; OR: 4.18; p < .001). Within the risk group, risk factors included age, number of years working in a professional activity with direct exposure to swine, geographic region and distance between residence and closest professional swine setting, while wearing gloves had a protective effect. Prevalence of total anti-HEV antibodies in swine was 88.2% (165/187) and HEV RNA was detected by real-time RT-PCR in 9.2% (16/173) swine stools. All HEV strains sequenced clustered within genotype 3. Some strains clearly belonged to subtype 3a, while another group of strains was related with subtypes 3b and 3 k but partial HEV sequences did not allow unequivocal subtype assignment. These findings suggest that the high HEV exposure in Cuban individuals with swine-related occupations could be due to enzootic HEV in certain regions, direct contact with infectious animals or their products as well as environmental contamination. 相似文献
69.
70.