Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Structural Crystallography Development in the 20th Century. Impact in the Biomedical Sciences and Perspectives in this Field

El desarrollo de la cristalografía estructural está estrechamente ligado a los avances en otras áreas de la ciencia y la tecnología: química, física y matemáticas, y a los adelantos en computación y robótica. Aunque el descubrimiento de los rayos X por Wilhelm Honrad Roentgen (1845-1923) tuvo lugar en 1895, el uso de la radiación en la determinación de la estructura de los cristales sólo se logró a partir del descubrimiento de Max von Laue (1876-1960), en 1912, según el cual un cristal expuesto a un haz de rayos X originaba sombras específicas. A partir de ese hecho, la estructura de cristales simples, como el cloruro de sodio y el diamante, fue determinada con el método de difracción de rayos X. Sin embargo, para moléculas complejas como las proteínas, que por sus medidas de peso molecular son catalogadas como macromoléculas, no fue fácil la determinación de su estructura tridimensional en esa época (1)

El primer mapa detallado de los genes de un hombre: un nuevo hito

Los progresos obtenidos en el estudio sobre los aspectos moleculares de la célula han tenido un gran impacto en la medicina. Desde el descubrimiento del ADN como el material que contiene la información genética —hecho por Osval Avery, en 1944 (1)—, pasando por la descripción de James Dewey Watson y Francis Harry Compton Crick de la estructura del ADN en 1953 (2), el desciframiento del código gené-tico (esfuerzos de tres grupos de investigación: Marshall W. Nirenberg, 1961; Severo Ochoa, 1965, y Har Gobind Khorana, 1969) (3-6), el desarrollo de métodos de secuenciación de los ácidos nucleicos (Sanger, 1977) (7), la técnica de la amplifi cación del ADN por reacción en cadena de la polimerasa (PCR, por sus siglas en inglés: polymerase chain reaction) (Mullis, 1985) (8), el inicio del Proyecto Genoma Humano (1989), hasta el desciframiento del genoma humano (9,10); la aplicación de la biología molecular y la biotecnología ha permitido los siguientes adelantos (11-14

Desarrollo de la cristalografía estructural en el siglo XX. Su impacto en las ciencias biomédicas y las perspectivas en este campo

-

Apoptosis: Therapeutic target in neurodegeneration and sepsis

La apoptosis celular se considera el principal mecanismo fisiopatológico asociado a la pérdida neuronal en las enfermedades neurodegenerativas. También durante la fase aguda de sepsis en que se presenta disfunción orgánica, se ha encontrado que existe un incremento en la tasa apoptótica del endotelio parenquimal y microvascular. De tal forma que las estrategias para prevenir la apoptosis (anti-apoptóticas) representan una valiosa herramienta para prevenir y/o retardar la aparición de la sintomatología en estos desórdenes, los cuales ocasionan una gran carga en morbi-mortalidad social y económica a nivel mundial. En la presente revisión se busca evidenciar que las estrategias anti-apoptóticas poseen un gran potencial terapéutico. En tal sentido, se revisarán algunas de estas potenciales terapias como los inhibidores de caspasas, la proteína C activada, la familia Bcl-2 y la vía de señalización mediada por PI3K/Akt.Cellular apoptosis has been considered as the main physiological mechanism underlying neuronal demise associated to neurodegenerative diseases. Apoptosis has also been described in parenquimal and microvascular endothelium in the acute phase of sepsis during multi-organic dysfunction. Therefore, strategies aimed to prevent apoptosis (anti-apoptotic) represent a valuable tool for prevention and/or retardation of the appearance of clinical symptoms in these disorders, which generate a large morbilitymortality, social and economic burden worldwide. The present review is aim to show that antiapoptotic strategies hold a great therapeutic potential. In this sense, we will review some of these potential therapies such as caspase inhibitors, activated protein C, Bcl-2 family and the PI3K/Akt signalling pathway

Proteolytic hydrolysis and purification of the LRP/alfa-2-macroglobulin receptor domain from ?-macroglobulins

A new, easier and efficient purification method, using Sephacryl and DEAE-Sephacel, of the C-terminal fragment of two ?-macroglobulins, ?2-M and PZP, is presented. Two larger peptides were identified for each protein as the C-terminal fragment, with molecular weights of ?30 kDa and the N-terminal sequences were determined to be SSTQDTV for ?2-M and VALHLS for PZP. The smaller peptides with molecular weights of 18 kDa correspond to a shorter C-terminal sequence of these proteins, and they were determined to be EEFPFA for ?2-M and ALKVQTV for PZP, with no interfering sequences detected. The results confirmed the discriminatory capacity of the purification procedure and the purity of the fragments. This new methodology facilitates biological studies of ?-macroglobulins, and will enable elucidation of the role the C-terminal region may exert to eliminate ?-macroglobulin-proteinases complexes from the circulation by the LRP/receptor. © 2006 Elsevier Inc. All rights reserved

Endothelial cell apoptosis induced by Colombian isolates of Staphylococcus aureus

La sepsis representa uno de los mayores problemas de salud a nivel mundial. Las estadísticas del Medicare database and the National Census Projections estiman que en Estados Unidos se reportan 750.000 casos de sepsis severa por año. Las tasas de mortalidad oscilan entre 28 y 59%. Staphylococcus aureus es uno de los patógenos mas frecuentemente asociados con sepsis. En sepsis ocasionada por S.aureus el endotelio es el tejido blanco potencial. Se ha postulado que los microorganismos internalizados inducen la apoptosis de la célula huésped con el fin de romper la barrera celular sin la activación de la respuesta inmune inmediata. El desprendimiento de las células apoptóticas también permite la dispersión bacteriana. En el presente estudio se analizó la capacidad de inducir apoptosis en células endoteliales de cinco aislamientos bacterianos provenientes de diferentes hospitales colombianos y de la comunidad de trabajadores de la salud portadores asintomáticos de S. aureus. Todos los aislamientos estudiados indujeron apoptosis endotelial dependiente del número de bacterias inoculadas.Sepsis represents a major world-wide health problem. Statistics from Medicare’s database and the National Census Report Projections estimate that in the United States there are 750,000 cases of severe sepsis in one year. The mortality rate oscillates between 28% and 59%. One of the pathogens which is most frequently related to sepsis is Staphylococcus aureus. During the staphylococal sepsis development, the endothelium is a potential target for injury. It has been hypothesized that internal micro-organisms induce host cell apoptosis to disrupt the cellular barrier without triggering an immediate immune response. The release of apoptotic cells also allows the spread of internal bacteria. The potential ability to induce endothelial apoptosis cellular activity was analyzed in five Colombian bacteria isolates recovered from hospitals and their communities working with health institutions studying asymptomatic carries of S.aureus. It was found that all the isolates induced apoptosis depending on those inoculated with the S.aureus bacteria

PAPEL PROTECTOR DE LA PROTEÍNA C ACTIVADA CONTRA LA APOPTOSIS EN MODELOS NEURONALES Y ENDOTELIALES

The neurodegenerative diseases are the result of the interaction of several factors that converge in neuronal death. Neuronalapoptosis is believe to have a mayor physiophatological role in this process which is accompanied by alterations in thevascular brain endothelium, contributing to alterations in the blood-brain barrier, a key regulator of neuronal survival/death equilibrium. Increased levels of the sphingolipid ceramide have been described in diverse neurodegenerative disorders and following several cellular stress insults and is believe to contribute to thepathophysiology of neuronal death