Cadena agroindustrial de la carne porcina la coordinación como puente para el desarrollo de ventajas competitivas

El propósito de este trabajo fue estudiar la performance de la cadena agroindustrial de la carne porcina argentina para identificar el potencial y las limitantes al desarrollo de la actividad en el país y su inserción en el exterior. Para esto se partió delimitando el estudio a partir de un mapa de la cadena. Luego, se realizó un diagnóstico sectorial mediante el desarrollo del Diamante de Porter y, dentro de éste, se abordó la relación entre dos de sus aristas: Las condiciones de los factores y las condiciones de la demanda, a partir del estudio de la relación entre el aumento de la producción y 3 variables explicativas (consumo, exportaciones y % de magro) entre 2009 y 2019. Los resultados mostraron un crecimiento de la actividad en los últimos años en los aspectos técnicos como comerciales (mayor eficiencia de conversión, mejoras en la calidad de las reses, aumento de la demanda interna y de las exportaciones). Sin embargo, se observa que esta mejora en la performance de la cadena agroindustrial, se acota a un reducido número de unidades productivas e industriales, que explican el 84% de la faena, con alto nivel tecnológico y formas innovadoras de coordinación. El modelo de regresión lineal simple mostró una alta correlación entre la producción, y las 3 variables estudiadas. Existe un gran espacio para la construcción de ventajas competitivas cuyo desarrollo requerirá de innovación en los diseños organizacionales de los actores, especialmente, los de menor escala.The purpose of this work was to study the performance of the Argentine pork agroindustrial  chain to identify the potential and the limitations to the development of the activity in the country and its insertion abroad. For this, the study was delimited from a map of the chain. Then, a sectoral diagnosis was made through the development of the Porter Diamond and, within this, the relationship between two of its edges was addressed: The conditions of the  factors and the conditions of the demand, based on the study of the relationship between the  increase in production and 3 explanatory variables (consumption, exports and% of lean) between 2009 and 2019. The results showed a growth in activity in recent years in technical  and commercial aspects (higher conversion efficiency, improvements in the quality of cattle,  increase in domestic demand and exports). However, it is observed that this improvement in  the performance of the agroindustrial chain is limited to a reduced number of productive and industrial units, which account for 84% of the work, with a high technological level and innovative forms of coordination. The simple linear regression model showed a high correlation between production and the 3 variables studied. There is a great space for the construction of  competitive advantages whose development will require innovation in the organizational designs of the actors, especially those of smaller scale. El propósito de este trabajo fue estudiar la performance de la cadena agroindustrial de la carne porcina argentina para identificar el potencial y las limitantes al desarrollo de la actividad en el país y su inserción en el exterior. Para esto se partió delimitando el estudio a partir de un mapa de la cadena. Luego, se realizó un diagnóstico sectorial mediante el desarrollo del Diamante de Porter y, dentro de éste, se abordó la relación entre dos de sus aristas: Las condiciones de los factores y las condiciones de la demanda, a partir del estudio de la relación entre el aumento de la producción y 3 variables explicativas (consumo, exportaciones y % de magro) entre 2009 y 2019. Los resultados mostraron un crecimiento de la actividad en los últimos años en los aspectos técnicos como comerciales (mayor eficiencia de conversión, mejoras en la calidad de las reses, aumento de la demanda interna y de las exportaciones). Sin embargo, se observa que esta mejora en la performance de la cadena agroindustrial, se acota a un reducido número de unidades productivas e industriales, que explican el 84% de la faena, con alto nivel tecnológico y formas innovadoras de coordinación. El modelo de regresión lineal simple mostró una alta correlación entre la producción, y las 3 variables estudiadas. Existe un gran espacio para la construcción de ventajas competitivas cuyo desarrollo requerirá de innovación en los diseños organizacionales de los actores, especialmente, los de menor escala

Influence of the NR3A subunit on NMDA receptor functions

Various combinations of subunits assemble to form the NMDA-type glutamate receptor (NMDAR), generating diversity in its functions. Here we review roles of the unique NMDAR subunit, NR3A, which acts in a dominant-negative manner to suppress receptor activity. NR3A-containing NMDARs display striking regional and temporal expression specificity, and, unlike most other NMDAR subtypes, they have a low conductance, are only modestly permeable to Ca2+, and pass current at hyperpolarized potentials in the presence of magnesium. While glutamate activates triheteromeric NMDARs composed of NR1/NR2/NR3A subunits, glycine is sufficient to activate diheteromeric NR1/NR3A-containing receptors. NR3A dysfunction may contribute to neurological disorders involving NMDARs, and the subunit offers an attractive therapeutic target given its distinct pharmacological and structural properties

Increased levels of rictor prevent mutant huntingtin-induced neuronal degeneration

Rictor associates with mTOR to form the mTORC2 complex, which activity regulates neuronal function and survival. Neurodegenerative diseases are characterized by the presence of neuronal dysfunction and cell death in specific brain regions such as for example Huntington's disease (HD), which is characterized by the loss of striatal projection neurons leading to motor dysfunction. Although HD is caused by the expression of mutant huntingtin, cell death occurs gradually suggesting that neurons have the capability to activate compensatory mechanisms to deal with neuronal dysfunction and later cell death. Here, we analyzed whether mTORC2 activity could be altered by the presence of mutant huntingtin. We observed that Rictor levels are specifically increased in the striatum of HD mouse models and in the putamen of HD patients. Rictor-mTOR interaction and the phosphorylation levels of Akt, one of the targets of the mTORC2 complex, were increased in the striatum of the R6/1 mouse model of HD suggesting increased mTORC2 signaling. Interestingly, acute downregulation of Rictor in striatal cells in vitro reduced mTORC2 activity, as shown by reduced levels of phospho-Akt, and increased mutant huntingtin-induced cell death. Accordingly, overexpression of Rictor increased mTORC2 activity counteracting cell death. Furthermore, normalization of endogenous Rictor levels in the striatum of R6/1 mouse worsened motor symptoms suggesting an induction of neuronal dysfunction. In conclusion, our results suggest that increased Rictor striatal levels could counteract neuronal dysfunction induced by mutant huntingtin

Temporal dynamics and neuronal specificity of Grin3a expression in the mouse forebrain

GluN3A subunits endow N-Methyl-D-Aspartate receptors (NMDARs) with unique biophysical, trafficking, and signaling properties. GluN3A-NMDARs are typically expressed during postnatal development, when they are thought to gate the refinement of neural circuits by inhibiting synapse maturation, and stabilization. Recent work suggests that GluN3A also operates in adult brains to control a variety of behaviors, yet a full spatiotemporal characterization of GluN3A expression is lacking. Here, we conducted a systematic analysis of Grin3a (gene encoding mouse GluN3A) mRNA expression in the mouse brain by combining high-sensitivity colorimetric and fluorescence in situ hybridization with labeling for neuronal subtypes. We find that, while Grin3a mRNA expression peaks postnatally, significant levels are retained into adulthood in specific brain regions such as the amygdala, medial habenula, association cortices, and high-order thalamic nuclei. The time-course of emergence and down-regulation of Grin3a expression varies across brain region, cortical layer of residence, and sensory modality, in a pattern that correlates with previously reported hierarchical gradients of brain maturation and functional specialization. Grin3a is expressed in both excitatory and inhibitory neurons, with strong mRNA levels being a distinguishing feature of somatostatin interneurons. Our study provides a comprehensive map of Grin3a distribution across the murine lifespan and paves the way for dissecting the diverse functions of GluN3A in health and disease. circuit refinement, excitatory glycine receptors, high-order thalamus, neocortical maturation, somatostatin interneuron

CHALLENGE 6: Exposing the roots of mental disorders

Mental disorders have devastating and increasing impact in our societies. CSIC researchers face the challenge of determining the biological and social causes and consequences of these disorders, and of finding efficient therapies. To these aims, the collaborative effort of neuroscientists, neurologists, psychiatrists, psychologists and human and social scientists, the use and development of state-of-the-art technologies and the contact with patient associations and pharma industry are required.Peer reviewe

Genetic Deletion of NR3A Accelerates Glutamatergic Synapse Maturation

Glutamatergic synapse maturation is critically dependent upon activation of NMDA-type glutamate receptors (NMDARs); however, the contributions of NR3A subunit-containing NMDARs to this process have only begun to be considered. Here we characterized the expression of NR3A in the developing mouse forebrain and examined the consequences of NR3A deletion on excitatory synapse maturation. We found that NR3A is expressed in many subcellular compartments, and during early development, NR3A subunits are particularly concentrated in the postsynaptic density (PSD). NR3A levels dramatically decline with age and are no longer enriched at PSDs in juveniles and adults. Genetic deletion of NR3A accelerates glutamatergic synaptic transmission, as measured by AMPAR-mediated postsynaptic currents recorded in hippocampal CA1. Consistent with the functional observations, we observed that the deletion of NR3A accelerated the expression of the glutamate receptor subunits NR1, NR2A, and GluR1 in the PSD in postnatal day (P) 8 mice. These data support the idea that glutamate receptors concentrate at synapses earlier in NR3A-knockout (NR3A-KO) mice. The precocious maturation of both AMPAR function and glutamate receptor expression are transient in NR3A-KO mice, as AMPAR currents and glutamate receptor protein levels are similar in NR3A-KO and wildtype mice by P16, an age when endogenous NR3A levels are normally declining. Taken together, our data support a model whereby NR3A negatively regulates the developmental stabilization of glutamate receptors involved in excitatory neurotransmission, synaptogenesis, and spine growth

Control of protein synthesis and memory by GluN3A-NMDA receptors through inhibition of GIT1/mTORC1 assembly

De novo protein synthesis is required for synapse modifications underlying stable memory encoding. Yet neurons are highly compartmentalized cells and how protein synthesis can be regulated at the synapse level is unknown. Here, we characterize neuronal signaling complexes formed by the postsynaptic scaffold GIT1, the mechanistic target of rapamycin (mTOR) kinase, and Raptor that couple synaptic stimuli to mTOR-dependent protein synthesis; and identify NMDA receptors containing GluN3A subunits as key negative regulators of GIT1 binding to mTOR. Disruption of GIT1/mTOR complexes by enhancing GluN3A expression or silencing GIT1 inhibits synaptic mTOR activation and restricts the mTOR-dependent translation of specific activity-regulated mRNAs. Conversely, GluN3A removal enables complex formation, potentiates mTOR-dependent protein synthesis, and facilitates the consolidation of associative and spatial memories in mice. The memory enhancement becomes evident with light or spaced training, can be achieved by selectively deleting GluN3A from excitatory neurons during adulthood, and does not compromise other aspects of cognition such as memory flexibility or extinction. Our findings provide mechanistic insight into synaptic translational control and reveal a potentially selective target for cognitive enhancementRamon y Cajal program RYC2014-15784, RETOS-MINECO SAF2016-76565-R, ERANET-Neuron JTC 2019 ISCIII AC19/00077 FEDER funds (to R.A.); RETOS-MINECO SAF2017-87928-R (to A.B.); an NIH grant (NS76637) and UTHSC College of Medicine funds (to S.J.T.); and NARSAD Independent Investigator Award and grants from the MINECO (CSD2008-00005, SAF2013-48983R, SAF2016-80895-R), Generalitat Valenciana (PROMETEO 2019/020)(to I.P.O.) and Severo-Ochoa Excellence Awards (SEV-2013-0317, SEV-2017-0723)Peer reviewe

Suppressing aberrant GluN3A expression rescues synaptic and behavioral impairments in Huntington's disease models

Huntington's disease is caused by an expanded polyglutamine repeat in the huntingtin protein (HTT), but the pathophysiological sequence of events that trigger synaptic failure and neuronal loss are not fully understood. Alterations in N-methyl-D-aspartate (NMDA)-type glutamate receptors (NMDARs) have been implicated. Yet, it remains unclear how the HTT mutation affects NMDAR function, and direct evidence for a causative role is missing. Here we show that mutant HTT redirects an intracellular store of juvenile NMDARs containing GluN3A subunits to the surface of striatal neurons by sequestering and disrupting the subcellular localization of the endocytic adaptor PACSIN1, which is specific for GluN3A. Overexpressing GluN3A in wild-type mouse striatum mimicked the synapse loss observed in Huntington's disease mouse models, whereas genetic deletion of GluN3A prevented synapse degeneration, ameliorated motor and cognitive decline and reduced striatal atrophy and neuronal loss in the YAC128 Huntington's disease mouse model. Furthermore, GluN3A deletion corrected the abnormally enhanced NMDAR currents, which have been linked to cell death in Huntington's disease and other neurodegenerative conditions. Our findings reveal an early pathogenic role of GluN3A dysregulation in Huntington's disease and suggest that therapies targeting GluN3A or pathogenic HTT-PACSIN1 interactions might prevent or delay disease progression

Nr3a-containing NMDA receptors promote neurotransmitter release and spike timing-dependent plasticity

Recent evidence suggests that presynaptic-acting NMDA receptors (preNMDARs) are important for neocortical synaptic transmission and plasticity. We found that unique properties of the Nr3a subunit enable preNMDARs to enhance spontaneous and evoked glutamate release and that Nr3a is required for spike timing–dependent long-term depression in the juvenile mouse visual cortex. In the mature cortex, Nr2b-containing preNMDARs enhanced neurotransmission in the absence of magnesium, indicating that presynaptic NMDARs may function under depolarizing conditions throughout life. Our findings indicate that Nr3a relieves preNMDARs from the dual-activation requirement of ligand-binding and depolarization; the developmental removal of Nr3a limits preNMDAR functionality by restoring this associative property

Efectividad de un protocolo de entrenamiento con el dispositivo de facilitación de movimiento cervical en sujetos con déficit de fuerza de la musculatura profunda cervical. Estudio piloto

Neck pain is one of the major public health problems, which has a great impact on the quality of people's lives, with a high prevalence and recurrence rate. The deep cervical muscles play a key role in neck stability. Deficits in deep cervical muscle strength are related to different clinical conditions: cervicogenic dizziness, cervical radiculopathy, chronic mechanical neck pain, cervical pain, and cervical instability. Training protocols can help to improve pain, cervical function, posture, and cross-sectional area. However, there are no training protocols in subjects with strength deficit in deep cervical muscles, including deep neck extensor and flexor muscles. The cervical device treatment (CDAT) allows us to train the cervical flexor and extensor muscle in a simple and comfortable way. The purpose of this study is to evaluate the clinical results in upper cervical range of motion, endurance, and self-perceived functional capacity by a training protocol with the new device for cervical treatment (GD) and the conventional training protocol (GH) versus a control group (GC) in subjects with cervical deep muscle strength deficit