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La anatomía es una ciencia de aprendizaje fácil, puesto que demanda al comienzo un esfuerzo de memoria visual. Pero los que no frecuentan asiduamente la anatomía, la olvidan pronto. Es por eso que el recurso de la disección sirve como herramienta crucial para el aprendizaje y entendimiento de la misma. Permite a partir del contacto directo con los órganos, el descubrimiento del cuerpo humano por la vista guiada por la mano. (Latarjet, Michel - 1983). En la Facultad de Ciencias Médicas de la UNR, complementando a las clases teóricas y en relación a los contenidos disciplinares, se dictan "mostraciones". Éstas son encuentros entre el estudiante y las distintas piezas cadavéricas que ofrece el Museo de Ciencias Morfológicas. Un instructor es quien se encarga de explicar y orientar al estudiante durante la misma. A diferencia de los seminarios, estas no cuentan con material audiovisual, sino con piezas cadavéricas. Es una metodología participativa en la que se enseña y se aprende a través de una tarea conjunta. Se realizó un estudio de casos y controles observacional y analítico. Se pidió colaboración a un grupo aleatorio de estudiantes pertenecientes a primer año. Ninguno de los estudiantes poseía hasta el momento del estudio noción alguna de anatomía de oído. Se dividió al grupo en tres subgrupos: GRUPO A, GRUPO B y GRUPO C. Al primer grupo de estudiantes se lo expuso utilizando el método de enseñanza tradicional de la institución, que consiste en un Seminario Disciplinar. El segundo grupo tuvo contacto con el método de enseñanza alternativo que consiste en la "Mostración Cadavérica". Y el tercer grupo es el denominado control, el cual no se expuso a ningún método de enseñanza. Al concluir cada clase, como método evaluativo objetivo se prosiguió a realizar una evaluación estandarizada tanto escrita como oral. Del análisis de datos se extrajo un resultado cualitativo (aprobado - no aprobado) a nivel global así como también uno diferencial por docente, resultado cuantitativo en cuanto a las calificaciones de cada grupo y se compararon los resultados de las clases con pequeños y grandes grupos entre sí (T de students: 0.0002). Según los resultados obtenidos podemos concluir que la modalidad de mostración cadavérica fue considerablemente más eficaz, lo que se encuentra plasmado en las evaluaciones realizadas, tanto orales como escritas. En segundo lugar, comparando las dos modalidades de enseñanza con el grupo control, queda expuesto que ambas representan un método de aprendizaje apreciable. [ABSTRACT FROM AUTHOR]

Genome editing in pigs for xenotransplantation has seen significant advances in recent years. This study compared three methodologies to generate gene-edited embryos, including co-injection of sperm together with the CRISPR-Cas9 system into oocytes, named ICSI-MGE (mediated gene editing); microinjection of CRISPR-Cas9 components into oocytes followed by in vitro fertilization (IVF), and microinjection of in vivo fertilized zygotes with the CRISPR-Cas9 system. Our goal was to knock-out (KO) porcine genes involved in the biosynthesis of xenoantigens responsible for the hyperacute rejection of interspecific xenografts, namely GGTA1, CMAH, and β4GalNT2. Additionally, we attempted to KO the growth hormone receptor (GHR) gene with the aim of limiting the growth of porcine organs to a size that is physiologically suitable for human transplantation. Embryo development, pregnancy, and gene editing rates were evaluated. We found an efficient mutation of the GGTA1 gene following ICSI-MGE, comparable to the results obtained through the microinjection of oocytes followed by IVF. ICSI-MGE also showed higher rates of biallelic mutations compared to the other techniques. Five healthy piglets were born from in vivo- derived embryos, all of them exhibiting biallelic mutations in the GGTA1 gene, with three displaying mutations in the GHR gene. No mutations were observed in the CMAH and β4GalNT2 genes. In conclusion, in vitro methodologies showed high rates of gene-edited embryos. Specifically, ICSI-MGE proved to be an efficient technique for obtaining homozygous biallelic mutated embryos. Lastly, only live births were obtained from in vivo -derived embryos showing efficient multiple gene editing for GGTA1 and GHR. • A comparison of three methodologies based on the introduction of CRISPR-Cas9 complex before (IVF), during (ICSI-MGE), and after fertilization (in vivo) for the production of genetically edited pigs was performed. • ICSI mediated gene editing proved to be an efficient technique for obtaining homozygous biallelic mutated pig embryos, similar to the microinjection of oocytes followed by IVF. • Live births were obtained from in vivo -derived embryos showing efficient multiple gene editing for GGTA1 and GHR genes. [ABSTRACT FROM AUTHOR]

The G171V mutation in the low-density lipoprotein receptor-related protein 5 (LRP5) leads to a high bone mass (HBM) phenotype. Studies using HBM transgenic mouse models have consistently found increased bone mass and whole-bone strength, but little attention has been paid to the composition of the bone matrix. The current study sought to determine if the cortical bone matrix composition differs in HBM and wild-type mice and to determine how much of the variance in bone material properties is explained by variance in matrix composition. Consistent with previous studies, HBM mice had greater cortical area, moment of inertia, ultimate force, bending stiffness, and energy to failure than wild-type animals. The increased energy to failure was primarily caused by a large increase in post-yield behavior, with no difference in pre-yield behavior. The HBM mice had increased mineral-to-matrix and collagen cross-link ratios, and decreased crystallinity, carbonate, and acid phosphate substitution as measured by Fourier transform infrared microspectroscopy, but no differences in crystal length, intra-fibular strains, and mineral spacing compared to wild-type controls, as measured by X-ray scattering. The largest between genotype difference in material properties was a twofold increase in the modulus of toughness in HBM mice. Step-wise regression analyses showed that the specific matrix compositional parameters most closely associated with material properties varied between the wild-type and HBM genotypes. Although the mechanisms controlling the paradoxical combination of more mineralized yet tougher bone in HBM mice remain to be fully explained, the findings suggest that LRP5 represents a target to not only build bone mass but also to improve bone quality. [ABSTRACT FROM AUTHOR]

Scientists have long suspected that compositionally zoned particles can form under far-from equilibrium precipitation conditions, but their inferences have been based on bulk solid and solution measurements. We are the first to directly observe nanoscale trace element compositional zonation in <10 µm-sized particles using X-ray fluorescence nanospectroscopy at the Hard X-ray Nanoprobe (HXN) Beamline at National Synchrotron Light Source II (NSLS-II). Through high-resolution images, compositional zonation was observed in barite (BaSO4) particles precipitated from aqueous solution, in which Sr2+ cations as well as HAsO42− anions were co-precipitated into (Ba,Sr)SO4 or Ba(SO4,HAsO4) solid solutions. Under high salinity conditions (NaCl ≥ 1.0 M), bands contained ~3.5 to ~5 times more trace element compared to the center of the particle formed in early stages of particle growth. Quantitative analysis of Sr and As fractional substitution allowed us to determine that different crystallographic growth directions incorporated trace elements to different extents. These findings provide supporting evidence that barite solid solutions have great potential for trace element incorporation; this has significant implications for environmental and engineered systems that remove hazardous substances from water. [ABSTRACT FROM AUTHOR]

Studying animal models furthers our understanding of Parkinson's disease (PD) pathophysiology by providing tools to investigate detailed molecular, cellular and circuit functions. Different versions of the neurotoxin-based 6-hydroxydopamine (6-OHDA) model of PD have been widely used in rats. However, these models typically assess the result of extensive and definitive dopaminergic lesions that reflect a late stage of PD, leading to a paucity of studies and a consequential gap of knowledge regarding initial stages, in which early interventions would be possible. Additionally, the better availability of genetic tools increasingly shifts the focus of research from rats to mice, but few mouse PD models are available yet. To address these, we characterize here the behavioral, neuronal and ultrastructural features of a graded-dose unilateral, single-injection, striatal 6-OHDA model in mice, focusing on early-stage changes within the first two weeks of lesion induction. We observed early onset, dose-dependent impairments of overall locomotion without substantial deterioration of motor coordination. In accordance, histological evaluation demonstrated a partial, dose-dependent loss of dopaminergic neurons of substantia nigra pars compacta (SNc). Furthermore, electron microscopic analysis revealed degenerative ultrastructural changes in SNc dopaminergic neurons. Our results show that mild ultrastructural and cellular degradation of dopaminergic neurons of the SNc can lead to certain motor deficits shortly after unilateral striatal lesions, suggesting that a unilateral dose-dependent intrastriatal 6-OHDA lesion protocol can serve as a successful model of the early stages of Parkinson's disease in mice. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) is a technique commonly used both in clinical and fundamental neurosciences. Classically, brain stimulation requires an implanted and wired electrode system to deliver stimulation directly to the target area. Although techniques such as temporal interference (TI) can provide stimulation at depth without involving any implanted electrodes, these methods still rely on a wired apparatus which limits free movement. Herein organic photocapacitors as untethered light‐driven electrodes which convert deep‐red light into electric current are reported. Pairs of these ultrathin devices can be driven using lasers at two different frequencies to deliver stimulation at depth via temporally interfering fields. This concept of laser TI stimulation using numerical modeling, tests with phantom brain samples, and finally in vivo tests is validated. Wireless organic photocapacitors are placed on the cortex and elicit stimulation in the hippocampus, while not delivering off‐target stimulation in the cortex. This laser‐driven wireless TI evokes a neuronal response at depth that is comparable to control experiments induced with deep brain stimulation protocols using implanted electrodes. This work shows that a combination of these two techniques—temporal interference and organic electrolytic photocapacitors—provides a reliable way to target brain structures requiring neither deeply implanted electrodes nor tethered stimulator devices. The laser TI protocol demonstrated here addresses two of the most important drawbacks in the field of DBS and thus holds potential to solve many issues in freely moving animal experiments or for clinical chronic therapy application. [ABSTRACT FROM AUTHOR]

The incorporation of fibre in the diet of pregnant sows improves the performance during pregnancy and increases voluntary consumption during lactation. Hydroponic green forage (HGF) constitutes a method of cultivation without soil in controlled environmental conditions. The aim of this study was to evaluate the impact of the supplementation with HGF in lactating sows on productive performance and to investigate the metabolic state through the analysis of different biochemical parameters. Twelve sows of the Porcine Productive Unit of the Faculty of Veterinary Sciences were randomly assigned to 2 feeding groups: control (conventional diet) or HGF (hydroponic green forage diet, conventional diet supplemented with HGF) from 7 days prepartum until day 28 postpartum. Productive parameters in sows (weaning-to-oestrus interval and back fat thickness) and in the litter (number of piglets born and weaned, and piglet weight) were evaluated. The effect of the diet in the metabolism of the sows was evaluated by biochemical parameters (total plasma proteins, albumin, glucose, urea and creatinine). Supplementation with HGF did not significantly affect the litter size nor productive parameters but produced a higher weight of piglets at day 60. Although lactation affected some biochemical parameters, no substantial negative consequences of the HGF supplemented diet were observed. Our results suggest that the use of HGF could be an option to take into account in porcine production with economic and environmental benefits. [ABSTRACT FROM AUTHOR]

The neck region of the Llama (Lama glama) has several structural and functional particularities in comparison to the same region of other domestic mammals. Among them, it is noticeable a distinctive venous circuit whose description is the purpose of this study.In order to perform the study, the veins of the neck of ten adult, male, wool type llamas were dissected with conventional technique. Previously to dissection, the veins were filled with a repletive substance.The authors describe the morphology of a venous circuit in which external jugular vein (v. jugularis externa), vertebral vein (v. vertebralis), and intervertebral veins (vv. Intervertebrales) are the main participating vessels. The distinctive feature is the fact that the metameric anastomoses between the forenamed veins leads to a jugular-vertebral by pass.The existence of venous shunts provides a circuit of collateral circulation, diverting the blood mainly towards the external jugular vein. Grazing habits and the length of the neck suggest that the vascular structure previously described facilitates the venous return, contributing to the regional blood stream control. [ABSTRACT FROM AUTHOR]

• Muscle larvae recovered from irradiated muscles were motile. • A dose of 0.31 kGy inactivated Trichinella pseudospiralis ML from wild boar meat. • The inactivation produced by irradiation on T. pseudospiralis ML was not reverted. Trichinellosis is a foodborne parasitic disease caused by Trichinella spp. Different methods, such as cooking, freezing and irradiation, have been suggested to inactivate the parasite in meat infected with Trichinella spp. The International Commission on Trichinellosis (ICT) recommends an irradiation dose of 0.3 kGy to inactivate Trichinella spp. larvae, but its effectiveness in all Trichinella species has not yet been demonstrated. Therefore, the objective of the present study was to determine the effectiveness of gamma radiation in treating wild boar meat to inactivate Trichinella pseudospiralis and Trichinella spiralis. Two wild boars (Sus scrofa) were each inoculated per os (PO) with 20,000 muscle larvae (ML) of Trichinella. One wild boar was inoculated with T. pseudospiralis and the other one with T. spiralis. Both wild boars were euthanized 20 weeks post infection (pi). A 250░g sample from each selected muscle type (side ribs, shoulder and upper forelegs) was obtained in duplicate from each animal. One group of samples was not irradiated (Gc; n░=░6) while the other group of samples was irradiated (Gt; n░=░6) at the Atomic Centre of the Argentinean National Commission of Atomic Energy (CNEA) with a minimum and maximum dose of 0.32–0.41 kGy. Twenty gram of each muscle from Gt and Gc were taken at 24░h, 7 days, 14 days and 21 days post-irradiation, and all samples were individually processed by means of artificial digestion. The ML were then inoculated into mice to evaluate the intestinal phase and the muscular phase. All recovered larvae from Gt and Gc samples showed integrity of the cuticle and active motility. Adult worms and ML were recovered from all mice inoculated with ML from Gc. However, no adult worms or ML were obtained in mice inoculated with ML from Gt. These results show the efficacy of irradiation to inhibit the development of T. pseudospiralis and T. spiralis in the host, which could possibly be extended to other non-encapsulated species, but further studies are needed to demonstrate this hypothesis. [ABSTRACT FROM AUTHOR]

• Trichinella patagoniensis and T. pseudospiralis produced a rapid immunological response. • T. patagoniensis had low infectivity in wild boars. • OD values from muscle juices and sera samples had positive correlations. Trichinellosis is a zoonotic disease, which represents a significant public health concern in some South American countries, such as Argentina and Chile. Its impact is essentially due to absence of adequate control measures on meat from game animals, as well as the presence of illegal slaughterhouses and the trade of meat products without being tested for this parasite. In Argentina, trichinellosis is an endemic disease. At present, Trichinella spiralis, Trichinella patagoniensis, Trichinella pseudospiralis, and Trichinella britovi have been detected in animals from Argentina. Until now, T. patagoniensis had only been found in mountain cougars (Puma concolor) in Argentina but there is limited information available. The present study intends to determine susceptibility, serological response and distribution of muscle larvae in wild boars infected with T. patagoniensis , T. spiralis and T. pseudospiralis. For each of the Trichinella species five wild boars were inoculated with 20,000 muscle larvae. Except for two specimens which died during the experiment, the animals were euthanized 19 weeks post infection (pi). Blood samples were collected throughout the study in order to determine the antibody kinetics. Also, nine muscle samples from each specimen were taken and analysed for determination of larval distribution. Additionally, four muscle samples were used to obtain muscle juices. Wild boars infected with T. patagoniensis showed little to no larvae in the muscle samples analysed while animals infected with T. spiralis and T. pseudospiralis had a significantly high larval load in all the samples analysed. Optical density (OD) values remained above the cut-off value throughout the experiment. This is the first study to characterize the biological aspects of T. patagoniensis in wild boars. [ABSTRACT FROM AUTHOR]