224 research outputs found

    Oral malignant melanomas and other head and neck neoplasms in Danish dogs - data from the Danish Veterinary Cancer Registry

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Head and neck cancers (HNC) are relatively common and often very serious diseases in both dogs and humans. Neoplasms originating in the head and neck region are a heterogeneous group. HNC often has an unfavourable prognosis and the proximity of the tissue structures renders extirpation of tumours with sufficient margins almost incompatible with preservation of functionality. In humans oral malignant melanoma (OMM) is extremely rare, but represents a particular challenge since it is highly aggressive as is the canine counterpart, which thus may be of interest as a spontaneous animal model.</p> <p>Methods</p> <p>Canine cases entered in the Danish Veterinary Cancer Registry (DVCR) from May 15th 2005 through February 29th 2008 were included in this study. Fisher's exact test was used to compare proportions of HNC in dogs and humans as well as proportions of surgically treated cases of OMM and squamous cell carcinomas (SCC). Also the proportions of benign and malignant neoplasms of different locations in dogs were compared using Fisher's exact test.</p> <p>Results</p> <p>A total of 1768 cases of neoplasias (679 malignant, 826 benign, 263 unknown) were submitted. Of all neoplasias HNC accounted for 7.2% (n = 128). Of these, 64 (50%) were malignant and 44 (34%) benign. The most common types of malignant neoplasia were SCC (18; 28% of malignant), OMM (13; 20% of malignant), soft tissue sarcoma (11; 17% of malignant) and adenocarcinoma (5; 11% of malignant). The most common types of benign neoplasms were adenoma (7; 16% of benign), polyps (6; 14% of benign) and fibroma (5; 11% of benign).</p> <p>Conclusions</p> <p>In the current study, the proportion of neoplasia in the head and neck region in dogs in Denmark was similar to other canine studies and significantly more common than in humans with a large proportion of malignancies. Spontaneous HNC in dogs thus, may serve as a model for HNC in humans.</p> <p>Canine OMM is a spontaneous cancer in an outbred, immune-competent large mammal population and could be a clinical model for OMM in humans.</p

    Mast cell tumours and other skin neoplasia in Danish dogs - data from the Danish Veterinary Cancer Registry

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The Danish Veterinary Cancer Registry (DVCR) was established in May 2005 to gather information about neoplasms in the Danish dog and cat populations. Practitioners from more than 60 clinics throughout Denmark have submitted data on these species. The objectives of the current study were, with a special focus on mast cell tumours (MCT) to investigate the occurrence, gender distribution, biological behaviour, locations, types, the diagnostic method used and treatment of skin neoplasms in dogs based on information reported to the DVCR.</p> <p>Methods</p> <p>From May 15<sup>th </sup>2005 through February 29<sup>th </sup>2008, reports on a total of 1,768 canine cases of neoplasia in the skin, subcutis or adnexa were submitted.) Of these, 765 cases (43%) were confirmed by cytology or histopathology.</p> <p>Results</p> <p>The majority of dogs had a benign neoplasm (66%) while 21% were cases of malignant neoplasia. The most commonly encountered malignant neoplasms were MCT and soft tissue sarcomas and for benign neoplasms, lipomas and histiocytomas were the most common. The location of the neoplasms were primarily in the cutis, subcutis or in the perianal region. The occurrence, gender distribution, biological behaviour and location of canine skin neoplasias in Denmark were similar to earlier reports, although some national variations occurred. A correlation between grade of MCT and the proportion of cases treated surgically was observed.</p> <p>Conclusions</p> <p>Population based cancer registries like the DVCR are of importance in the collection of non-selected primary information about occurrence and distribution of neoplasms. The DVCR provides detailed information on cases of skin neoplasms in dogs and may serve as a platform for the study of sub-sets of neoplastic diseases (e.g. MCT) or subgroups of the canine population (e.g. a specific breed).</p

    Enhancing Mathematical Reasoning in Primary School With the Strategic Board Game Othello

    Get PDF
    This study explores how the board game Othello can enhance primary school students' mathematical reasoning. Mathematical reasoning is increasingly emphasized in international mathematics curricula, yet both teachers and students face challenges in teaching and learning this important skill. Research shows that strategic games, like Othello, can develop thinking abilities related to mathematical reasoning by providing a context for students to engage in reflective thinking, anticipate future moves, and develop reasoning strategies. However, there is a need to understand how teachers can effectively utilize these games in the classroom to foster mathematical reasoning. We address this, through a design-based research approach consisting of a hermeneutic literature study and the development of design principles for a teaching intervention in a fifth-grade classroom. Data from the intervention is collected through participant observations and group interviews. The findings suggest that Othello can serve as a context for students to engage in mathematical reasoning by making and justifying claims and presenting logical arguments. The study proposes three design principles to scaffold mathematical reasoning during Othello gameplay. These principles focus on introducing and reinforcing the use of the "if...then" formulation, promoting exploratory talk, encouraging reflection on strategies, and fostering collaborative reasoning. The results indicate that the design principles positively impacted students' ability to reason mathematically. This paper contributes to the field of mathematics education and game-based learning by providing a practice-oriented perspective on designing mathematical instruction for reasoning using a specific board game in a primary school setting. The findings offer insights into the potential of strategic board games like Othello to enhance students' mathematical reasoning skills. The design principles proposed in this study can guide teachers in developing effective instructional approaches to support students' mathematical reasoning development.This study explores how the board game Othello can enhance primary school students' mathematical reasoning. Mathematical reasoning is increasingly emphasized in international mathematics curricula, yet both teachers and students face challenges in teaching and learning this important skill. Research shows that strategic games, like Othello, can develop thinking abilities related to mathematical reasoning by providing a context for students to engage in reflective thinking, anticipate future moves, and develop reasoning strategies. However, there is a need to understand how teachers can effectively utilize these games in the classroom to foster mathematical reasoning. We address this, through a design-based research approach consisting of a hermeneutic literature study and the development of design principles for a teaching intervention in a fifth-grade classroom. Data from the intervention is collected through participant observations and group interviews. The findings suggest that Othello can serve as a context for students to engage in mathematical reasoning by making and justifying claims and presenting logical arguments. The study proposes three design principles to scaffold mathematical reasoning during Othello gameplay. These principles focus on introducing and reinforcing the use of the "if...then" formulation, promoting exploratory talk, encouraging reflection on strategies, and fostering collaborative reasoning. The results indicate that the design principles positively impacted students' ability to reason mathematically. This paper contributes to the field of mathematics education and game-based learning by providing a practice-oriented perspective on designing mathematical instruction for reasoning using a specific board game in a primary school setting. The findings offer insights into the potential of strategic board games like Othello to enhance students' mathematical reasoning skills. The design principles proposed in this study can guide teachers in developing effective instructional approaches to support students' mathematical reasoning development.</p

    Age and metabolic risk factors associated with oxidatively damaged DNA in human peripheral blood mononuclear cells

    Get PDF
    Aging is associated with oxidative stress-generated damage to DNA and this could be related to metabolic disturbances. This study investigated the association between levels of oxidatively damaged DNA in peripheral blood mononuclear cells (PBMCs) and metabolic risk factors in 1,019 subjects, aged 18-93 years. DNA damage was analyzed as strand breaks by the comet assay and levels of formamidopyrimidine (FPG-) and human 8-oxoguanine DNA glycosylase 1 (hOGG1)-sensitive sites There was an association between age and levels of FPG-sensitive sites for women, but not for men. The same tendency was observed for the level of hOGG1-sensitive sites, whereas there was no association with the level of strand breaks. The effect of age on oxidatively damaged DNA in women disappeared in multivariate models, which showed robust positive associations between DNA damage and plasma levels of triglycerides, cholesterol and glycosylated hemoglobin (HbA(1c)). In the group of men, there were significant positive associations between alcohol intake, HbA(1c) and FPG-sensitive sites in multivariate analysis. The levels of metabolic risk factors were positively associated with age, yet only few subjects fulfilled all metabolic syndrome criteria. In summary, positive associations between age and levels of oxidatively damaged DNA appeared mediated by age-related increases in metabolic risk factors

    Role of ammonia in NAFLD: An unusual suspect

    Get PDF
    Mechanistically, the symptomatology and disease progression of non-alcoholic fatty liver disease (NAFLD) remain poorly understood, which makes therapeutic progress difficult. In this review, we focus on the potential importance of decreased urea cycle activity as a pathogenic mechanism. Urea synthesis is an exclusive hepatic function and is the body’s only on-demand and definitive pathway to remove toxic ammonia. The compromised urea cycle activity in NAFLD is likely caused by epigenetic damage to urea cycle enzyme genes and increased hepatocyte senescence. When the urea cycle is dysfunctional, ammonia accumulates in liver tissue and blood, as has been demonstrated in both animal models and patients with NAFLD. The problem may be augmented by parallel changes in the glutamine/glutamate system. In the liver, the accumulation of ammonia leads to inflammation, stellate cell activation and fibrogenesis, which is partially reversible. This may be an important mechanism for the transition of bland steatosis to steatohepatitis and further to cirrhosis and hepatocellular carcinoma. Systemic hyperammonaemia has widespread negative effects on other organs. Best known are the cerebral consequences that manifest as cognitive disturbances, which are prevalent in patients with NAFLD. Furthermore, high ammonia levels induce a negative muscle protein balance leading to sarcopenia, compromised immune function and increased risk of liver cancer. There is currently no rational way to reverse reduced urea cycle activity but there are promising animal and human reports of ammonia-lowering strategies correcting several of the mentioned untoward aspects of NAFLD. In conclusion, the ability of ammonia-lowering strategies to control the symptoms and prevent the progression of NAFLD should be explored in clinical trials

    Low fitness is associated with abdominal adiposity and low-grade inflammation independent of BMI

    Get PDF
    Up to 30% of obese individuals are metabolically healthy. Metabolically healthy obese (MHO) individuals are characterized by having low abdominal adiposity, low inflammation level and low risk of developing metabolic comorbidity. In this study, we hypothesize that cardiorespiratory fitness (fitness) is a determinant factor for the MHO individuals and aim to investigate the associations between fitness, abdominal adiposity and low-grade inflammation within different BMI categories.Data from 10,976 individuals from the general population, DANHES 2007-2008, on waist circumference, fitness and C-reactive protein (hsCRP) were analysed using multiple linear and median quantile regressions.In men, an inverse association between fitness (+5 mL min-1 kg-1) and waist circumference (-1.45 cm; 95% CI: -1.55 to -1.35 cm; p<0.001), and an inverse association between fitness (+5 mL min-1 kg-1) and hsCRP (-0.22 mg/L; 95% CI: -0.255 to -0.185 mg/L; p<0.001) was found, all independent of BMI. Similarly in women, an inverse association between fitness (+5 mL min-1 kg-1) and waist circumference (-1.15 cm; 95% CI: -1.25 to -1.0 cm; p<0.001), and an inverse association between fitness (+5 mL min-1 kg-1) and hsCRP (-0.26 mg/L; 95% CI: -0.3 to -0.22 mg/L; p<0.001) was found, all independent of BMI. Additionally, significant positive associations between waist circumference and hsCRP were found for both men and women, independently of BMI.Fitness was found to be inversely associated with both abdominal adiposity and low-grade inflammation independent of BMI. These data suggest that, in spite of BMI, high fitness levels lead to a reduction in abdominal fat mass and low-grade inflammation

    Effect of propofol and remifentanil on cerebral perfusion and oxygenation in pigs:a systematic review

    Get PDF
    The objective of this review is to evaluate the existing literature with regard to the influence of propofol and remifentanil total intravenous anaesthesia (TIVA) on cerebral perfusion and oxygenation in healthy pigs. Anaesthesia has influence on cerebral haemodynamics and it is important not only in human but also in veterinary anaesthesia to preserve optimal regulation of cerebral haemodynamics. Propofol and remifentanil are widely used in neuroanaesthesia and are increasingly used in experimental animal studies. In translational models, the pig has advantages compared to small laboratory animals because of brain anatomy, metabolism, neurophysiological maturation, and cerebral haemodynamics. However, reported effects of propofol and remifentanil on cerebral perfusion and oxygenation in pigs have not been reviewed. An electronic search identified 99 articles in English. Title and abstract screening selected 29 articles for full-text evaluation of which 19 were excluded with reasons. Of the 10 peer-reviewed articles included for review, only three had propofol or remifentanil anaesthesia as the primary study objective and only two directly investigated the effect of anaesthesia on cerebral perfusion and oxygenation (CPO). The evidence evaluated in this systematic review is limited, not focused on propofol and remifentanil and possibly influenced by factors of potential importance for CPO assessment. In one study of healthy pigs, CPO measures were within normal ranges following propofol-remifentanil anaesthesia, and addition of a single remifentanil bolus did not affect regional cerebral oxygen saturation (rSO(2)). Even though the pool of evidence suggests that propofol and remifentanil alone or in combination have limited effects on CPO in healthy pigs, confirmative evidence is lacking
    • …
    corecore