317 research outputs found

    On the Estimation of Euler Equations in the Presence of a Potential Regime Shift

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    The concept of a peso problem is formalized in terms of a linear Euler equation and a nonlinear marginal model describing the dynamics of the exogenous driving process. It is shown that, using a threshold autoregressive model as a marginal model, it is possible to produce time-varying peso premia. A Monte Carlo method and a method based on the numerical solution of integral equations are considered as tools for computing conditional future expectations in the marginal model. A Monte Carlo study illustrates the poor performance of the generalized method of moment (GMM) estimator in small and even relatively large samples. The poor performance is particularly acute in the presence of a peso problem but is also serious in the simple linear case.peso problem; Euler equations; GMM; threshold autoregressive models

    Mucopolysaccharidosis VI in cats - clarification regarding genetic testing

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    Debate. Published online: 02 July 2016.The release of new DNA-based diagnostic tools has increased tremendously in companion animals. Over 70 different DNA variants are now known for the cat, including DNA variants in disease-associated genes and genes causing aesthetically interesting traits. The impact genetic tests have on animal breeding and health management is significant because of the ability to control the breeding of domestic cats, especially breed cats. If used properly, genetic testing can prevent the production of diseased animals, causing the reduction of the frequency of the causal variant in the population, and, potentially, the eventual eradication of the disease. However, testing of some identified DNA variants may be unwarranted and cause undo strife within the cat breeding community and unnecessary reduction of gene pools and availability of breeding animals. Testing for mucopolysaccharidosis Type VI (MPS VI) in cats, specifically the genetic testing of the L476P (c.1427T>C) and the D520N (c.1558G>A) variants in arylsulfataseĀ B (ARSB), has come under scrutiny. No health problems are associated with the D520N (c.1558G>A) variant, however, breeders that obtain positive results for this variant are speculating as to possible correlation with health concerns. Birman cats already have a markedly reduced gene pool and have a high frequency of the MPS VI D520N variant. Further reduction of the gene pool by eliminating cats that are heterozygous or homozygous for only the MPS VI D520N variant could lead to more inbreeding depression effects on the breed population. Herein is debated the genetic testing of the MPS VI D520N variant in cats. Surveys from different laboratories suggest the L476P (c.1427T>C) disease-associated variant should be monitored in the cat breed populations, particularly breeds with Siamese derivations and outcrosses. However, the D520N has no evidence of association with disease in cats and testing is not recommended in the absence of L476P genotyping. Selection against the D520N is not warranted in cat populations. More rigorous guidelines may be required to support the genetic testing of DNA variants in all animal species.Leslie A. Lyons, Robert A. Grahn, Francesca Genova, Michela Beccaglia, John J. Hopwood and Maria Longer

    Spinal manipulation and mobilisation in the treatment of infants, children, and adolescents: a systematic scoping review

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    PURPOSE: To i) identify and map the available evidence regarding effectiveness and harms of spinal manipulation and mobilisation for infants, children and adolescents with a broad range of conditions; ii) identify and synthesise policies, regulations, position statements and practice guidelines informing their clinical use. DESIGN: Systematic scoping review, utilising four electronic databases (PubMed, Embase, CINHAL and Cochrane) and grey literature from root to 4(th) February 2021. PARTICIPANTS: Infants, children and adolescents (birth toā€‰<ā€‰18Ā years) with any childhood disorder/condition. INTERVENTION: Spinal manipulation and mobilisation OUTCOME MEASURES: Outcomes relating to common childhood conditions were explored. METHOD: Two reviewers (A.P., L.L.) independently screened and selected studies, extracted key findings and assessed methodological quality of included papers using Joanna Briggs Institute Checklist forĀ Systematic ReviewsĀ and Research Synthesis, Joanna Briggs Institute Critical Appraisal Checklist for Text and Opinion Papers, Mixed Methods Appraisal Tool and International Centre for Allied Health Evidence GuidelineĀ Quality Checklist. A descriptive synthesis of reported findings was undertaken using a levels of evidence approach. RESULTS: Eighty-seven articles were included. Methodological quality of articles varied. Spinal manipulation and mobilisation are being utilised clinically by a variety of health professionals to manage paediatric populations with adolescent idiopathic scoliosis (AIS), asthma, attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), back/neck pain, breastfeeding difficulties, cerebral palsy (CP), dysfunctional voiding, excessive crying, headaches, infantile colic, kinetic imbalances due to suboccipital strain (KISS), nocturnal enuresis, otitis media, torticollis and plagiocephaly. The descriptive synthesis revealed: no evidence to explicitly support the effectiveness of spinal manipulation or mobilisation for any condition in paediatric populations. Mild transient symptoms were commonly described in randomised controlled trials and on occasion, moderate-to-severe adverse events were reported in systematic reviews of randomised controlled trials and other lower quality studies. There was strong to very strong evidence for ā€˜no significant effectā€™ of spinal manipulation for managing asthma (pulmonary function), headache and nocturnal enuresis, and inconclusive or insufficient evidence for all other conditions explored. There is insufficient evidence to draw conclusions regarding spinal mobilisation to treat paediatric populations with any condition. CONCLUSION: Whilst some individual high-quality studies demonstrate positive results for some conditions, our descriptive synthesis of the collective findings does not provide support for spinal manipulation or mobilisation in paediatric populations for any condition. Increased reporting of adverse events is required to determine true risks. Randomised controlled trials examining effectiveness of spinal manipulation and mobilisation in paediatric populations are warranted. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12887-022-03781-6

    Mitochondrial DNA control region variation in Sanfratellano horse and two other Sicilian autochthonous breeds

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    Mitochondrial D-loop hypervariable region was analysed in 20 Sanfratellano and two other Sicilian autochthonous horse breeds (20 Sicilian Oriental Purebred and 20 Sicilian Indigenous) in order to investigate matrilineal genetic diversity. A total of 20 different haplotypes were identified sequencing a fragment of 397 bp; overall, haplotypes showed 31 polymorphic sites (7.8%). High diversity was detected in Sanfratellano (11 haplotypes) and Sicilian Indigenous (13 haplotypes), whereas only one haplotype was found in Sicilian Oriental Purebred. Sanfratellano sequences were compared with those belonging to the other Sicilian autochthonous horses and 118 sequences selected from the GenBank database in order to calculate the statistics of molecular diversity. Six haplotypes were exclusive of Sanfratellano which shares haplotype C, D, H, and O with the Sicilian Indigenous and haplotype U with the Sicilian Oriental Purebred; not significant differentiation was found between Sanfratellano and Sicilian Indigenous. BLAST search showed Sicilian haplotypes overlap with the database sequences but for three. Phylogenetic analysis did not show monophyletic group for Sanfratellano samples or the other breeds included in this analysis

    Cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH) mutations associated with the domestic cat AB blood group

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    <p>Abstract</p> <p>Background</p> <p>The cat has one common blood group with two major serotypes, blood type A that is dominant to type B. A rare type AB may also be allelic and is suspected to be recessive to A and dominant to B. Cat blood type antigens are defined, N-glycolylneuraminic acid (NeuGc) is associated with type A and N-acetylneuraminic acid (NeuAc) with type B. The enzyme <it>cytidine monophospho-N-acetylneuraminic acid hydroxylase </it>(<it>CMAH</it>) determines the sugar bound to the red cell by converting NeuAc to NeuGc. Thus, mutations in <it>CMAH </it>may cause the A and B blood types.</p> <p>Results</p> <p>Genomic sequence of <it>CMAH </it>from eight cats and the cDNA of four cats representing all blood types were analyzed to identify causative mutations. DNA variants consistent with the blood types were genotyped in over 200 cats. Five SNPs and an indel formed haplotypes that were consistent with each blood type.</p> <p>Conclusion</p> <p>Mutations in type B cats likely disrupt the gene function of <it>CMAH</it>, leading to a predominance of NeuAc. Type AB concordant variants were not identified, however, cDNA species suggest an alternative allele that activates a downstream start site, leading to a CMAH protein that would be altered at the 5' region. The cat AB blood group system is proposed to be designated by three alleles, <it>A </it>> <it>a</it><sup><it>ab </it></sup>> <it>b</it>. The <it>A </it>and <it>b CMAH </it>alleles described herein can distinguish type A and type B cats without blood sample collections. <it>CMAH </it>represents the first blood group gene identified outside of non-human primates and humans.</p

    Quantitative Trait Loci affecting the somatic cell score on chromosome 4 and 26 in Italian Holstein cattle

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    This work aimed to confirm previously reported quantitative trait loci (QTL) affecting the somatic cell score (SCS) in dairy cattle on Bos taurus autosomes (BTA) 4 and 26. A granddaughter design with selective genotyping was implemented that included half-sib families from 12 male lines of Italian Holstein cattle. The animals were genotyped for 5 microsatellite markers each on regions of BTA 4 (average marker spacing 9.42 cM) and BTA 26 (average marker spacing 5.26 cM), previously reported by other authors as carrying QTL for somatic cell count. Quantitative trait loci analyses were performed using interval mapping by regressing sire breeding values for SCS onto genotype probabilities at 1-cM intervals along the 2 chromosome regions. Breeding values for SCS were estimated for the whole population using a test-day repeatability animal model. Results were not significant on a chromosome basis, but a possible QTL was found at BM4505 on BTA 26, confirming this region for further studies of QTL affecting SCS in the Italian Holstein population

    Correlation between neurotrasmitter levels and anxietyrelated behaviours in cats

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    Introduction: The present study aims to evaluate the existing correlations between neurotransmitter levels and anxiety-related aggressive behaviour. Materials and methods: 22 adult cats (age > 6months; no pharmacological therapy for behaviour problems) were grouped according to three different levels of aggressive behaviour: Group 1 (N=11): rare aggressive attacks, anxiety and aggressive-related behaviour problems reported by the owner; Group 2 (N=4): frequent aggressive attacks (n attacks > 12/year); Group 3 (N=7): control, no aggressive attacks reported by the owners. An accurate questionnaire focusing on anxiety and aggressive behaviour was filled in for every subject and evaluated by a DVM certified Specialist in Veterinary Behavioural Medicine. Blood samples were collected in EDTA for all the subjects for neurotransmitters analysis (standard blood processing procedures for HPLC neurotransmitter analysis were applied). HPLC analysis was carried out for the following neurotransmitters: Dopamine precursor LDOPA, dopamine DA, noradrenalin NA, adrenalin A, serotonin SE levels in plasma and platelets; 5-hidrossiindolacetic acid HIAA (serotonin metabolite) and Homovanillic acid (dopamine metabolite) in platelets. SAS \uae statistic package was applied to data analysis: FREQ, MEAN and NPAR1WAY procedures were applied; the analysis of variance was carried out using a Kruscal-Wallis one-way ANOVA.Results: The results indicate that during the history taking session, the origin of the cat, age at weaning and human family structure are very helpful in aggressive behaviour evaluation, furthermore nervousness, shyness and fearfulness related information are closely linked to anxiety related problems. Higher levels of NA (pg/ml), DA (pg/ml), LDOPA plasma (pg/ml), LDOPA platelet (pg/ml) were found in Control group (P 640.05). A correlation between neurotransmitter concentrations and anxiety related behavioural problems has been calculated. Discussion: The obtained results suggest, in particular, that the reduction in platelet DA levels could be related to aggressive behaviour towards animals and human beings. Further analysis is needed to improve the knowledge of the complex relations between nervous system and behaviour. In addition the investigation of the genetic basis of behaviour could supply powerful tools in the understanding of anxiety and aggressiveness in companion animals
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