134 research outputs found
The Influence of Fatteners Dry and Liquid Diet on Slaughter Traits of Carcass Sides
The study was conducted on 700 fattening pigs, three breed half blood with Duroc as a terminal breed ((Large White x Landrace) x Duroc). The pigs were divided into the two groups according to diet: dry and liquid nutrition. Each group consisted of 350 fattening pigs and used the same feed mixtures in prefattening (CP-3) and fattening (ST). During the period from 24.8 to 60kg they were fed with a CP-3, a crude protein content of 16.37%. During the period from 60kg until the end they were fed with ST, a crude protein content of 15.3%. Muscle tissue processed half-carcasses in slaughterhouses were determined by a device that determines the value of S (fat thickness) and M (muscle thickness) using "method one point." Fat thickness skin in mm, measured 7 cm lateral to the central (median) cutting, in the amount between the second and third ribs of the tail. The thickness of the muscle in mm was measured at the same place as the thickness of the bacon. The results show that the fatling fed dry food had significantly higher carcass weight (80.41: 78.51 kg, p<0.05), backfat thickness (16.55: 15.31 mm, p<0.05), weight (muscle 55.80: 53.82, p<0.05), but a lower percentage of meat (56.6: 57.3, p<0.05) as compared to pigs fed liquid food. In finishing pigs fed dry food, between carcass weight and backfat thickness and muscle thickness a positive and significant correlation (0.4267 and 0.4290, p<0.05) was found and between carcass weight and lean meat a significant negative correlation (-0. 4236 and p<0.05). Between backfat thickness and lean meat in the carcass a negative and significant correlation (-0.8534, p<0.05) was found and between muscle thickness and lean meat a positive and significant correlation (0.2857, p<0.05). In finishing pigs fed liquid food, between carcass weight and backfat thickness and muscle thickness a positive and significant correlation (0.1800 and 0.3705, p<0.05) was found and between carcass weight and lean meat a significant negative correlation (-0. 2178; p <0.05). Between backfat thickness and percentage of meat in the carcass negative and significant correlation (-0.8692, p<0.05) was found and between muscle thickness and lean meat a positive and significant correlation (0.3168, p<0.05)
Modelo celular de retinitis pigmentaria basado en células de pluripotencia inducida
Motivación: La retinitis pigmentaria (RP) se caracteriza por una degeneración de los fotorreceptores y de las células del epitelo pigmentario (RPE) que se manifiesta con ceguera nocturna seguida por constricción del campo visual y posterior pérdida global de la visión. El mecanismo molecular de esta y otras distrofias retinianas hereditarias es desconocido por la escasez de material humano y la poca fiabilidad de los modelos animales debido a las diferencias fisiológicas y estructurales entre la retina humana y la de los roedores.El desarrollo de células de pluripotencia inducida (iPSC) nos ofrece una oportunidad sin precedentes para obtener células de pacientes con la enfermedad específica debido a su alta capacidad de expansión y diferenciación a cualquier tipo celular humano. Esta tecnología se ha usado para crear el modelo de RP in vitro que reproduce el fenotipo clínico. Las células iPS derivadas de fibroblastos de paciente de RP e individuo sano se han caracterizado y diferenciado a RPE. El paciente es portador de la mutación en el gen MERTK(Ser331fs), responsable de la trasmision de la señal en la fagocitosis de los segmentos exteriores de los fotorreceptores, una actividad que realizan las células RPE diariamente, por lo que esperamos que las células RPE de paciente resulten defectuosas en el ensayo de fagocitosis.Métodos: La células iPS de paciente e individuo sano se caracterizaron por Inmunocitoquímica para marcadores de pluripotencia y su capacidad de diferenciación en las tres capas germinales mediante el ensayo de teratoma en ratones inmunodeprimidos. Las iPSC se han diferenciado hacia células RPE mediante protocolo de diferenciación espontánea observándose la morfologia típica de células RPE. La expresión de genes y proteínas específicos de RPE se detectó mediante RT-PCR y Western blott.Resultados: Las iPSC de ambos pacientes fueron teñidas con marcadores de pluripotencia y han sido capaces de desarrollar las tres capas germinales (ectodermo, mesodermo y endodermo) en el ensayo de teratoma, no encontrando diferencias entre ambas. Una vez diferenciadas en RPE (iPS-RPE) se observó la diferencia en la expresion de la proteína MERTK, mientras las demás proteinas están expresadas igualmente en ambos.Conclusiones: Hemos conseguido obtener células RPE especificas de paciente que carecen de la expresión de la proteína MERTK. En los siguientes ensayos, esperamos ver defectos en fagocitosis con las iPS-RPE de paciente
Noninvasive MRI measures of microstructural and cerebrovascular changes during normal swine brain development
The swine brain is emerging as a potentially valuable translational animal model of neurodevelopment and offers the ability to assess the impact of experimentally induced neurological disorders. The goal for this study was to characterize swine brain development using noninvasive MRI measures of microstructural and cerebrovascular changes. Thirteen pigs at various postnatal ages (2.3-43.5 kg) were imaged on a 1.5-Tesla MRI system. Microstructural changes were assessed using diffusion tensor imaging measures of mean diffusivity and fractional anisotropy. Cerebrovascular changes were assessed using arterial spin labeling measures of baseline cerebral blood flow (CBF) and the cerebrovascular reactivity (CVR) of the blood-oxygen level dependent (BOLD) MRI signal to CO2. We found a positive logarithmic relationship for regional tissue volumes and fractional anisotropy with body weight, which is similar to the pattern reported in the developing human brain. Unlike in the maturing human brain, no consistent changes in mean diffusivity or baseline CBF with development were observed. Changes in BOLD CVR exhibited a positive logarithmic relationship with body weight, which may impact the interpretation of functional MRI results at different stages of development. This animal model can be validated by applying the same noninvasive measures in humans. Copyright © 2011 International Pediatric Research Foundation, Inc
Volume Characteristics of Landslides Triggered by the MW 7.8 2016 Kaikōura Earthquake, New Zealand, Derived From Digital Surface Difference Modeling
We use a mapped landslide inventory coupled with a 2‐m resolution vertical difference model covering an area of 6,875 km2 to accurately constrain landslide volume‐area relationships. We use the difference model to calculate the source volumes for landslides triggered by the MW 7.8 Kaikōura, New Zealand, earthquake of 14 November 2016. Of the 29,519 mapped landslides in the inventory, 28,394 are within the analysis area, and of these, we have calculated the volume of 17,256 source areas that are ≥90% free of debris. Of the 28,394 landslides, about 80% are classified as soil or rock avalanches and the remainder as mainly translational slides. Our results show that both the soil avalanches and the rock avalanches, ignoring their source geology, have area to volume power‐law scaling exponents (γ) of 0.921 to 1.060 and 1.040 to 1.138, respectively. These are lower than the γ values of 1.1–1.3 (for soil) and 1.3–1.6 (for rock) reported in the literature for undifferentiated landslide types. They are, however, similar to those γ values estimated from other coseismic landslide inventories. In contrast, for 50 selected rotational, translational (planar slide surfaces), or compound slides, where much of the debris remains in the source area, we found γ values range between 1.46 and 1.47, indicating that their slide surfaces were considerably deeper than those landslides classified as avalanches. This study, like previous studies on coseismic landslides, shows that soil and rock avalanches (disrupted landslides) are the dominant landslide type triggered by earthquakes and that they tend to be shallow.Key PointsWe use a 2‐m resolution vertical difference model to estimate source volumes for 17,256 landslides with sources ≥90% free of debris triggered by the MW7.8 2016 Kaikōura EarthquakeThe model was derived by subtracting a tectonically adjusted pre‐EQ surface model from a post‐EQ model, covering an area of 6,875 km2Landslide trigger mechanism, type/failure mode, and source material are critical for accurate estimation of landslide volumes from source‐area geometriesPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156166/2/jgrf21176.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156166/1/jgrf21176_am.pd
Genetic diversity and population structure of six autochthonous pig breeds from Croatia, Serbia, and Slovenia
Background: The importance of local breeds as genetic reservoirs of valuable genetic variation is well established. Pig breeding in Central and South-Eastern Europe has a long tradition that led to the formation of several local pig breeds. In the present study, genetic diversity parameters were analysed in six autochthonous pig breeds from Slovenia, Croatia and Serbia (Banija spotted, Black Slavonian, Turopolje pig, Swallow-bellied Mangalitsa, Moravka and Krskopolje pig). Animals from each of these breeds were genotyped using microsatellites and single nucleotide polymorphisms (SNPs). The results obtained with these two marker systems and those based on pedigree data were compared. In addition, we estimated inbreeding levels based on the distribution of runs of homozygosity (ROH) and identified genomic regions under selection pressure using ROH islands and the integrated haplotype score (iHS). Results: The lowest heterozygosity values calculated from microsatellite and SNP data were observed in the Turopolje pig. The observed heterozygosity was higher than the expected heterozygosity in the Black Slavonian, Moravka and Turopolje pig. Both types of markers allowed us to distinguish clusters of individuals belonging to each breed. The analysis of admixture between breeds revealed potential gene flow between the Mangalitsa and Moravka, and between the Mangalitsa and Black Slavonian, but no introgression events were detected in the Banija spotted and Turopolje pig. The distribution of ROH across the genome was not uniform. Analysis of the ROH islands identified genomic regions with an extremely high frequency of shared ROH within the Swallow-bellied Mangalitsa, which harboured genes associated with cholesterol biosynthesis, fatty acid metabolism and daily weight gain. The iHS approach to detect signatures of selection revealed candidate regions containing genes with potential roles in reproduction traits and disease resistance. Conclusions: Based on the estimation of population parameters obtained from three data sets, we showed the existence of relationships among the six pig breeds analysed here. Analysis of the distribution of ROH allowed us to estimate the level of inbreeding and the extent of homozygous regions in these breeds. The iHS analysis revealed genomic regions potentially associated with phenotypic traits and allowed the detection of genomic regions under selection pressure
Pacing with restoration of respiratory sinus arrhythmia improved cardiac contractility and the left ventricular output: a translational study
Introduction: Respiratory sinus arrhythmia (RSA) is a prognostic value for patients with heart failure and is defined as a beat-to-beat variation of the timing between the heart beats. Patients with heart failure or patients with permanent cardiac pacing might benefit from restoration of RSA. The aim of this translational, proof-of-principle study was to evaluate the effect of pacing with or without restored RSAon parameters of LV cardiac contractility and the cardiac output
Unraveling the developmental roadmap toward human brown adipose tissue
Increasing brown adipose tissue (BAT) mass and activation is a therapeutic strategy to treat obesity and complications. Obese and diabetic patients possess low amounts of BAT, so an efficient way to expand their mass is necessary. There is limited knowledge about how human BAT develops, differentiates, and is optimally activated. Accessing human BAT is challenging, given its low volume and anatomical dispersion. These constraints make detailed BAT-related developmental and functional mechanistic studies in humans virtually impossible. We have developed and characterized functionally and molecularly a new chemically defined protocol for the differentiation of human pluripotent stem cells (hPSCs) into brown adipocytes (BAs) that overcomes current limitations. This protocol recapitulates step by step the physiological developmental path of human BAT. The BAs obtained express BA and thermogenic markers, are insulin sensitive, and responsive to β-adrenergic stimuli. This new protocol is scalable, enabling the study of human BAs at early stages of development
Excitotoxic cell death induces delayed proliferation of endogenous neuroprogenitor cells in organotypic slice cultures of the rat spinal cord
The aim of the present report was to investigate whether, in the mammalian spinal cord, cell death induced by transient excitotoxic stress could trigger activation and proliferation of endogenous neuroprogenitor cells as a potential source of a lesion repair process and the underlying time course. Because it is difficult to address these issues in vivo, we used a validated model of spinal injury based on rat organotypic slice cultures that retain the fundamental tissue cytoarchitecture and replicate the main characteristics of experimental damage to the whole spinal cord. Excitotoxicity evoked by 1 h kainate application produced delayed neuronal death (40%) peaking after 1 day without further losses or destruction of white matter cells for up to 2 weeks. After 10 days, cultures released a significantly larger concentration of endogenous glutamate, suggesting functional network plasticity. Indeed, after 1 week the total number of cells had returned to untreated control level, indicating substantial cell proliferation. Activation of progenitor cells started early as they spread outside the central area, and persisted for 2 weeks. Although expression of the neuronal progenitor phenotype was observed at day 3, peaked at 1 week and tapered off at 2 weeks, very few cells matured to neurons. Astroglia precursors started proliferating later and matured at 2 weeks. These data show insult-related proliferation of endogenous spinal neuroprogenitors over a relatively brief time course, and delineate a narrow temporal window for future experimental attempts to drive neuronal maturation and for identifying the factors regulating this process. \ua9 2013 Macmillan Publishers Limited. All rights reserved
In vivo MRI and ex vivo histological assessment of the cardioprotection induced by ischemic preconditioning, postconditioning and remote conditioning in a closed-chest porcine model of reperfused acute myocardial infarction: importance of microvasculature
BACKGROUND: Cardioprotective value of ischemic post- (IPostC), remote (RIC) conditioning in acute myocardial infarction (AMI) is unclear in clinical trials. To evaluate cardioprotection, most translational animal studies and clinical trials utilize necrotic tissue referred to the area at risk (AAR) by magnetic resonance imaging (MRI). However, determination of AAR by MRI' may not be accurate, since MRI-indices of microvascular damage, i.e., myocardial edema and microvascular obstruction (MVO), may be affected by cardioprotection independently from myocardial necrosis. Therefore, we assessed the effect of IPostC, RIC conditioning and ischemic preconditioning (IPreC; positive control) on myocardial necrosis, edema and MVO in a clinically relevant, closed-chest pig model of AMI. METHODS AND RESULTS: Acute myocardial infarction was induced by a 90-min balloon occlusion of the left anterior descending coronary artery (LAD) in domestic juvenile female pigs. IPostC (6 x 30 s ischemia/reperfusion after 90-min occlusion) and RIC (4 x 5 min hind limb ischemia/reperfusion during 90-min LAD occlusion) did not reduce myocardial necrosis as assessed by late gadolinium enhancement 3 days after reperfusion and by ex vivo triphenyltetrazolium chloride staining 3 h after reperfusion, however, the positive control, IPreC (3 x 5 min ischemia/reperfusion before 90-min LAD occlusion) did. IPostC and RIC attenuated myocardial edema as measured by cardiac T2-weighted MRI 3 days after reperfusion, however, AAR measured by Evans blue staining was not different among groups, which confirms that myocardial edema is not a measure of AAR, IPostC and IPreC but not RIC decreased MVO. CONCLUSION: We conclude that IPostC and RIC interventions may protect the coronary microvasculature even without reducing myocardial necrosis
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