RESUMEN
OBJECTIVE: The most used model for joint instability is the canine anterior cruciate ligament transection (ACLT)-model. The ACLT-model can be extended with a medial meniscectomy (MX) (i.e., ACLT-MX-model) to avoid unintentional, and with that variable, meniscal damage. The present study compares the ACLT-MX-model with the more recently introduced Groove-model on longitudinal measurements of osteophyte formation and gait as a surrogate marker of pain and disability, in addition to structural endpoint parameters. METHODS: Degenerative joint damage was induced Labrador dogs according to the ACLT-MX-model (n=7) or Groove-model (n=7). Every 4 weeks radiographs were taken to analyze osteophyte formation. Every 2 weeks gait was recorded using force-plate analysis. Joints were analyzed for features of degeneration 12 weeks after surgery. RESULTS: Both models showed similar osteophyte formation and gait changes for both experimental and contra-lateral control joints, although more pronounced for the ACLT-MX-model. This was supported by the structural endpoint measurements. Cartilage integrity, chondrocyte activity and synovial inflammation revealed similar characteristics of degenerative joint disease in both groups, again more pronounced in the ACLT-MX-model. CONCLUSIONS: The ACLT-MX-model demonstrates characteristics of joint degeneration that are related to moderate to severe osteoarthritis with clear synovial inflammatory activity. The Groove-model is a less painful and a significantly milder model of joint degeneration. The latter model might be more suitable to study subtle changes as a result of intervention than the more robust ACLT-MX-model.
Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Cartílago Articular/fisiología , Inestabilidad de la Articulación/fisiopatología , Osteoartritis/fisiopatología , Regeneración/fisiología , Rodilla de Cuadrúpedos/fisiología , Animales , Ligamento Cruzado Anterior/patología , Artralgia/etiología , Artralgia/fisiopatología , Cartílago Articular/lesiones , Cartílago Articular/patología , Condrocitos/patología , Perros , Marcha/fisiología , Inflamación , Inestabilidad de la Articulación/patología , Modelos Animales , Osteofito/patologíaRESUMEN
A deletion in the copper metabolism (Murr1) domain containing 1 (COMMD1) gene is associated with hepatic copper toxicosis in dogs, yet evidence of copper retention in COMMD1-depleted hepatic cells has not been shown. In a dog hepatic cell line, we analysed the copper metabolic functions after an 80% (mRNA and protein) COMMD1 reduction with COMMD1-targeting siRNAs. Exposure to 64Cu resulted in a significant increase in copper retention in COMMD1-depleted cells. COMMD1-depleted cells were almost three times more sensitive to high extracellular copper concentrations. Copper-mediated regulation of metallothionein gene expression was enhanced in COMMD1-depleted cells. Based on the increased copper accumulation and enhanced cellular copper responses upon COMMD1 reduction, we conclude that COMMD1 has a major regulatory function for intracellular copper levels in hepatic cells.
Asunto(s)
Proteínas Portadoras/metabolismo , Cobre/metabolismo , Regulación de la Expresión Génica/genética , Hígado/citología , Interferencia de ARN , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteínas Portadoras/genética , Línea Celular , Perros , Hígado/metabolismo , Metalotioneína/metabolismo , ARN Interferente Pequeño/genéticaRESUMEN
Thirty-three metastatic melanoma patients were vaccinated according to a phase I-II study with an allogeneic melanoma cell line that was genetically modified by transfection with a plasmid containing the gene encoding human interleukin 2 (IL-2). The cell line expresses the major melanoma-associated antigens and the HLA class I alleles HLA-A1, -A2, -B8, and Cw7. All patients shared one or more HLA class I alleles with this cell line vaccine. Patients were immunized by three vaccinations, each consisting of 60 x 106 irradiated (100 Gy) melanoma cells (secreting 120 ng of IL-2/10(6) cells/24 hr) administered subcutaneously at weekly intervals for 3 consecutive weeks. Side effects of treatment consisted of swelling of locoregional lymph nodes and induration at the site of injection, i.e., a delayed-type hypersensitivity (DTH) reaction. In three patients, vaccination induced inflammatory responses in distant metastases containing necrosis or apoptosis along with T cell infiltration. Apoptosis occurred only in Bcl-2-negative areas, not in Bcl-2-expressing parts of the metastases. Two other patients experienced complete or partial regression of subcutaneous metastases. Seven patients had protracted stabilization (4 to >46 months) of soft tissue metastases, including one patient who developed vitiligo after vaccination. Immune responses to the vaccine could be detected in 67% of the 27 patients measured. Vaccination was shown to induce a variable change in the number of anti-vaccine cytotoxic T lymphocytes (CTLs) in peripheral blood, which did not correlate with response to treatment. However, in two of five patients the frequency of anti-autologous tumor CTLs measured was significantly higher than before vaccination. This study demonstrates the feasibility, safety, and therapeutic potential of vaccination of humans with allogeneic, gene-modified tumor cells, and that frequencies of vaccine-specific CTLs among patient lymphocytes can be determined by using a modified limited dilution analysis (LDA).
Asunto(s)
Vacunas contra el Cáncer/farmacología , Interleucina-2/metabolismo , Melanoma/secundario , Melanoma/terapia , Adulto , Anciano , Antígenos de Neoplasias/genética , Vacunas contra el Cáncer/genética , Femenino , Antígeno HLA-A1/metabolismo , Antígeno HLA-A2/metabolismo , Antígeno HLA-B8/metabolismo , Antígenos HLA-C/metabolismo , Humanos , Inmunoterapia/métodos , Inflamación/inmunología , Interleucina-2/genética , Interleucina-2/farmacología , Antígeno MART-1 , Masculino , Melanoma/mortalidad , Antígenos Específicos del Melanoma , Persona de Mediana Edad , Monofenol Monooxigenasa/genética , Proteínas de Neoplasias/genética , Tasa de Supervivencia , Linfocitos T Citotóxicos/inmunología , Resultado del Tratamiento , Células Tumorales CultivadasRESUMEN
Recent studies describe families with both elevated plasma HRG levels and thrombosis. In order to study the possibility that allelic variants of the HRG locus are associated with differences in HRG level, we studied linkage between HRG levels and a dinucleotide repeat polymorphism in a Dutch family which was selected on the presence of both thrombosis and elevated plasma HRG levels. No other known risk factors from thrombosis were found in this family. Linkage was calculated between the dinucleotide repeat and the HRG level considering the HRG level as a quantitative phenotype assuming a population prevalence of elevated HRG of 5%. Two classes of HRG levels were defined by a mean and a variance: one class with normal HRG levels and a second class with high HRG levels. Using a mean HRG level of 99% for individuals with a normal HRG level and 145% for individuals with high HRG, a maximum lod score of 4.17 (odds in favour of linkage of 22,000:1) was found at a recombination fraction of 0, indicating linkage. Considering the pedigree, an association was found between the presence of a specific allele (no. 6) of the dinucleotide repeat polymorphism and plasma HRG levels. Family members carrying allele 6 were found to have higher HRG plasma levels compared with family members lacking allele 6 (149% v 109% respectively). We conclude that in this family, linkage is found between the HRG locus and the HRG level, and that a HRG gene coupled to allele 6 of the dinucleotide polymorphism is associated with elevated plasma HRG levels. No evidence was found for a causal relationship between elevated plasma HRG levels and thrombosis in this family.
Asunto(s)
Alelos , Glicoproteínas/sangre , Proteínas/metabolismo , Trombosis/genética , Anciano , Secuencia de Bases , Coagulación Sanguínea , Femenino , Ligamiento Genético , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Polimorfismo Genético , Secuencias Repetitivas de Ácidos Nucleicos , Trombosis/sangreRESUMEN
Histidine-rich glycoprotein (HRG) is a non-enzymatic glycoprotein that acts as a modulator of several plasma proteins involved in coagulation and fibrinolysis. The contributions of genetic and environmental influences to inter-individual variation in plasma levels of HRG were studied in 160 Dutch families consisting of adolescent twin pairs and their parents. Results showed that 69% of the variance in plasma HRG concentrations could be accounted for by genetic factors. Heritability was the same in males and females and in parents and their offspring. There was no association between HRG levels of husband and wife and no evidence was found for the influence of shared family environment on the resemblance between relatives.
Asunto(s)
Padres , Proteínas/análisis , Gemelos , Adolescente , Adulto , Factores de Edad , Ambiente , Femenino , Genotipo , Humanos , Funciones de Verosimilitud , Masculino , Persona de Mediana Edad , Proteínas/genética , Factores Sexuales , Gemelos Dicigóticos , Gemelos MonocigóticosRESUMEN
The influence of dietary calcium on calcium metabolism was investigated in growing dogs that reach an adult body weight similar to that of humans. Seven groups of dogs (n greater than or equal to 5) were raised on a diet with a composition meeting the National Research Council (NRC) requirements (1974), but differing in calcium content, with or without a constant ratio to phosphorus. Control dogs fed 1.1% calcium and 0.9% phosphorus (all on a dry matter basis) were fed ad libitum (n = 10) or in restricted amounts (n = 6); dogs fed high calcium (3.3%) diets received either 0.9% phosphorus (n = 6) or 3.0% phosphorus (n = 6); dogs fed low calcium (0.55%) diets received either 0.9% phosphorus (n = 5 + 6) or 0.5% phosphorus (n = 8). Food intake, circulating total calcium and inorganic phosphorus concentrations and calcium metabolism, with 45Ca kinetics, were studied at 8, 14, 20 and 26 wk of age. Except for the difference in food intake in two groups at 14 wk (i.e., 0.55% calcium-0.9% phosphorus higher and 3.3% calcium-0.9% phosphorus lower, respectively, than the controls) no differences were noticed during the rest of the study. The mean plasma calcium concentrations did not differ between groups during the studies, whereas that of inorganic phosphorus revealed temporal aberrations in two groups. An absorption coefficient alpha of 45-66% was found for the control group. High and low calcium diets gave rise to values of 23-43% and 70-97%, respectively, for alpha irrespective of the phosphorus content of the diet.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Calcio de la Dieta/administración & dosificación , Calcio/metabolismo , Perros/metabolismo , Fósforo Dietético/administración & dosificación , Alimentación Animal , Animales , Cruzamiento , Calcio/sangre , Perros/crecimiento & desarrollo , Ingestión de Alimentos , Femenino , Masculino , Fósforo/sangreRESUMEN
The low-dose dexamethasone suppression test and the urinary corticoid/creatinine ratio were assessed in 166 and 150 dogs, respectively, for their value in the diagnosis of hyperadrenocorticism. The diagnostic accuracy of the low-dose dexamethasone suppression test was 0.83, with a 95 per cent confidence interval from 0.76 to 0.88. The urinary corticoid/creatinine ratio had a diagnostic accuracy of 0.91 with a 95 per cent confidence interval from 0.85 to 0.95. The high predictive value of a negative corticoid/creatinine ratio (0.98; confidence interval 0.80 to 1.00) and the low cost of this test makes it preferable for screening purposes to the low-dose dexamethasone suppression test for which the predictive value of a negative test was calculated as 0.5g (confidence interval 0.43 to 0.73).