Caficultura y cambio climático en Nicaragua: Refexiones sobre el papel de las políticas públicas y las cooperativas

En el marco de un proyecto denominado “Planes de Inversión en Agricultura Sostenible Adaptada al Clima” implementado por CEDECO, HIVOS, Bioversity Internacional, el Centro Mundial de Agroforestería (ICRAF) y la Universidad de Vermont, Bioversity International llevó a cabo un estudio sobre el marco político e institucional que rodea la producción del café por pequeños productores en Nicaragua. Los objetivos del mismo fueron entender y documentar cómo las políticas públicas que regulan la caficultura en Nicaragua así como el modo de funcionar de las cooperativas agrícolas influyen en las prácticas agrícolas de los pequeños productores de café en Nicaragua, y en particular su capacidad para adoptar medidas que les permitan adaptar la producción cafetalera a los efectos del cambio climático

Long-term controlled delivery of rhBMP-2 from collagen-hydroxyapatite scaffolds for superior bone tissue regeneration.

The clinical utilization of recombinant human bone morphogenetic protein 2 (rhBMP-2) delivery systems for bone regeneration has been associated with very severe side effects, which are due to the non-controlled and non-targeted delivery of the growth factor from its collagen sponge carrier post-implantation which necessitates supraphysiological doses. However, rhBMP-2 presents outstanding regenerative properties and thus there is an unmet need for a biocompatible, fully resorbable delivery system for the controlled, targeted release of this protein. With this in mind, the purpose of this work was to design and develop a delivery system to release low rhBMP-2 doses from a collagen-hydroxyapatite (CHA) scaffold which had previously been optimized for bone regeneration and recently demonstrated significant healing in vivo. In order to enhance the potential for clinical translation by minimizing the design complexity and thus upscaling and regulatory hurdles of the device, a microparticle and chemical functionalization-free approach was chosen to fulfill this aim. RhBMP-2 was combined with a CHA scaffold using a lyophilization fabrication process to produce a highly porous CHA scaffold supporting the controlled release of the protein over the course of 21days while maintaining in vitro bioactivity as demonstrated by enhanced alkaline phosphatase activity and calcium production by preosteoblasts cultured on the scaffold. When implanted in vivo, these materials demonstrated increased levels of healing of critical-sized rat calvarial defects 8weeks post-implantation compared to an empty defect and unloaded CHA scaffold, without eliciting bone anomalies or adjacent bone resorption. These results demonstrate that it is possible to achieve bone regeneration using 30 times less rhBMP-2 than INFUSE®, the current clinical gold standard; thus, this work represents the first step of the development of a rhBMP-2 eluting material with immense clinical potential

Controlled release of vascular endothelial growth factor from spray-dried alginate microparticles in collagen-hydroxyapatite scaffolds for promoting vascularization and bone repair.

A major limitation with current tissue-engineering approaches is creating functionally vascularized constructs that can successfully integrate with the host; this often leads to implant failure, due to avascular necrosis. In order to overcome this, the objective of the present work was to develop a method to incorporate growth factor-eluting alginate microparticles (MPs) into freeze-dried, collagen-based scaffolds. A collagen-hydroxyapatite (CHA) scaffold, previously optimized for bone regeneration, was functionalized for the sustained delivery of an angiogenic growth factor, vascular endothelial growth factor (VEGF), with the aim of facilitating angiogenesis and enhancing bone regeneration. VEGF was initially encapsulated in alginate MPs by spray-drying, producing particles of \u3c 10 µm in diameter. This process was found to effectively encapsulate and control VEGF release while maintaining its stability and bioactivity post-processing. These VEGF-MPs were then incorporated into CHA scaffolds, leading to homogeneous distribution throughout the interconnected scaffold pore structure. The scaffolds were capable of sustained release of bioactive VEGF for up to 35 days, which was proficient at increasing tubule formation by endothelial cells in vitro. When implanted in vivo in a rat calvarial defect model, this scaffold enhanced vessel formation, resulting in increased bone regeneration compared to empty-defect and VEGF-free scaffolds. This biologically functionalized scaffold, composed entirely of natural-based materials, may offer an ideal platform to promote angiogenesis and tissue regeneration. Copyright © 2015 John Wiley \u26 Sons, Ltd

Observable implications of geometrical and dynamical aspects of freeze-out in heavy ion collisions

Using an analytical parameterization of hadronic freeze-out in relativistic heavy ion collisions, we present a detailed study of the connections between features of the freeze-out configuration and physical observables. We focus especially on anisotropic freeze-out configurations (expected in general for collisions at finite impact parameter), azimuthally-sensitive HBT interferometry, and final-state interactions between non-identical particles. Model calculations are compared with data taken in the first year of running at RHIC; while not perfect, good agreement is found, raising the hope that a consistent understanding of the full freeze-out scenario at RHIC is possible, an important first step towards understanding the physics of the system prior to freeze-out.Comment: 36 pages, 56 figures, 2 tables; version accepted for publication in PRC: some figures, references and discussion added; now also discusses classical versus quantum statistic

Reconstrucción del ligamento cruzado anterior con plastia mixta de semitendinoso y fibra de Kennedy-Lad

—Se han evaluado los resultados de la reconstrucción del ligamento cruzado anterior (LCA) con una plastia mixta de tendón del semitendinoso y fibra sintética de KennedyLAD en veinticinco pacientes con un mínimo de dos años de seguimiento postoperatorio (media de treinta y ocho meses). Se trataba en todos los casos de lesiones crónicas donde la cirugía consistió en la reconstrucción del LCA y meniscectomías parciales cuando fueron necesarias. La evaluación se llevó a cabo mediante pruebas funcionales (Lysholm) y clínicas (Marshall), pruebas de estabilidad manual (Lachman, pivot, cajón neutro anterior), medidas instrumentales de estabilidad con artrómetro (KT-1000), índice de actividad y apreciación subjetiva. Los datos indican que el comportamiento de la plastia es adecuado en el 92% de los casos proporcionando a los pacientes una función articular satisfactoria en su vida diaria incluyendo la actividad deportiva.The authors assess the results of the anterior cruciate ligament (ACL) reconstruction by means of a semitendinous tendon and Kennedy LAD composite graft. Minimum followup has been two years (mean of thirty eight months). In every cases the lesion was considered as chronic and surgery consisted of ACL reconstruction and partial meniscectomy if neccessary. Studies performed to asses the results included: functional (Lysholm) and clinical (Marshall) tests, manual stability tests (Lachman, pivot-shift, neutral anterior drawer), instrumented stability measurement (KT-1000 arthrometer), activity score and subjective patient self-assessment. The data collected indicate that the performance of the composite graft is adequate in 92% of the cases, allowing the patients a satisfactory knee joint function in their daily life including sporting activities

Caficultura y cambio climático en Nicaragua: Refexiones sobre el papel de las políticas públicas y las cooperativas

En Nicaragua el café ocupa el tercer lugar de la superficie cultivada (11%) y, después del maíz y del frijol, es el rubro agrícola que más contribuye al PIB (10%). El 96% de las fincas cafetaleras están en manos de pequeños productores (menos de 20 manzanas1), los cuales representan un 50% del área cultivada del café. Alrededor del 95% del café en Nicaragua se produce bajo sombra y utiliza diversas variedades como Caturra, Borbón, Maragogipe, Catimor, Típica y Cautilla. El café es una fuente muy importante de empleo en el sector rural. Se estima que esta actividad genera un 53% del empleo agrícola y el 14% del total de todo el país. Alrededor del 85% de la producción total de café se vende en el mercado externo y un 15% se consume localmente. Una gran parte de la exportación se realiza a través de intermediarios: solo un 46% de la producción exportable viene directamente del pequeño productor. Existen grandes inequidades dentro del sector del café en Nicaragua, donde grandes empresas concentran gran parte de los ingresos. Nicaragua cuenta con 44.000 productores que cultivan café como rubro principal como parte de un sistema integrado. Esto quiere decir que además de café, cultivan maíz, frijol, hortalizas y musáceas, cítricos, y raíces como la malanga. De ellos, unos 30.000 son pequeños productores que cultivan áreas de entre tan solo 0.5 y 5 manzanas y a los que les resulta muy difícil acceder al financiamiento, tecnologías y apoyo técnico necesarios para modernizar su producción. Los productores medianos y grandes, por otro lado, tienen acceso o al menos cuentan con los recursos suficientes para poder pagar los servicios que les facilitan mejorar su producción

Acute Demyelinating Disease after Oral Therapy with Herbal Extracts

Central nervous system demyelinating processes such as multiple sclerosis and acute disseminated encephalomyelitis constitute a group of diseases not completely understood in their physiopathology. Environmental and toxic insults are thought to play a role in priming autoimmunity. The aim of the present report is to describe a case of acute demyelinating disease with fatal outcome occurring 15 days after oral exposure to herbal extracts

Potential implications of the use of digital sequence information on genetic resources for the three objectives of the Convention on Biological Diversity. A submission from CGIAR to the Secretary of the Convention on Biological Diversity (CBD)

This report has been submitted by CGIAR in response to an invitation issued by the Secretary of the Convention on Biological Diversity (CBD) calling on “relevant organizations and stakeholders to submit views and relevant information on any potential implications of the use of digital sequence information on genetic resources for the three objectives of the Convention” as input to the "Meeting of the Ad Hoc Technical Expert Group on Digital Sequence Information on Genetic Resources", 13 - 16 February 2018, Montreal, Canada. CGIAR experience to date confirms that digital genomic sequence data can play important roles in the management and sustainable use of biological diversity and in the sharing of benefits associated with the use of that diversity. Technological capacities to generate genomic sequence data have accelerated faster than capacities to enable practical use of this information. Relatively small investments in the initial generation of genomic sequences, must then be coupled with significantly larger investments to comparatively analyse genomic sequences, to link genetic variability to useful phenotypic traits or performance, to ‘optimize’ those traits, and ultimately, to develop new crop varieties for release and use in farmers’ fields. CGIAR underscores the importance of capacity building for developing country research and development organizations to generate and use genomic sequence information as part of their own conservation and crop improvement programs, and to be able to participate on equal footing in internationally coordinated and funded research and development programs. The most important benefit to be shared from the use of genomic sequence information in agricultural research and development and plant breeding is improved food and livelihood security. Other non-monetary benefits are farmers’ improved access to technologies, enhanced institutional capacities of developing country research organizations, shared research results, and local and regional economic development