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1.
Conserv Biol ; : e14284, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38785034

RESUMEN

Contemporary wildlife disease management is complex because managers need to respond to a wide range of stakeholders, multiple uncertainties, and difficult trade-offs that characterize the interconnected challenges of today. Despite general acknowledgment of these complexities, managing wildlife disease tends to be framed as a scientific problem, in which the major challenge is lack of knowledge. The complex and multifactorial process of decision-making is collapsed into a scientific endeavor to reduce uncertainty. As a result, contemporary decision-making may be oversimplified, rely on simple heuristics, and fail to account for the broader legal, social, and economic context in which the decisions are made. Concurrently, scientific research on wildlife disease may be distant from this decision context, resulting in information that may not be directly relevant to the pertinent management questions. We propose reframing wildlife disease management challenges as decision problems and addressing them with decision analytical tools to divide the complex problems into more cognitively manageable elements. In particular, structured decision-making has the potential to improve the quality, rigor, and transparency of decisions about wildlife disease in a variety of systems. Examples of management of severe acute respiratory syndrome coronavirus 2, white-nose syndrome, avian influenza, and chytridiomycosis illustrate the most common impediments to decision-making, including competing objectives, risks, prediction uncertainty, and limited resources.


Replanteamiento del manejo de problemas por enfermedades de fauna mediante el análisis de decisiones Resumen El manejo actual de las enfermedades de la fauna es complejo debido a que los gestores necesitan responder a una amplia gama de actores, varias incertidumbres y compensaciones difíciles que caracterizan los retos interconectados del día de hoy. A pesar de que en general se reconocen estas complejidades, el manejo de las enfermedades tiende a plantearse como un problema científico en el que el principal obstáculo es la falta de conocimiento. El proceso complejo y multifactorial de la toma decisiones está colapsado dentro de un esfuerzo científico para reducir la incertidumbre. Como resultado de esto, las decisiones contemporáneas pueden estar simplificadas en exceso, depender de métodos heurísticos simples y no considerar el contexto legal, social y económico más amplio en el que se toman las decisiones. De manera paralela, las investigaciones científicas sobre las enfermedades de la fauna pueden estar lejos de este contexto de decisiones, lo que deriva en información que puede no ser directamente relevante para las preguntas pertinentes de manejo. Proponemos replantear los obstáculos para el manejo de enfermedades de fauna como problemas de decisión y abordarlos con herramientas analíticas de decisión para dividir los problemas complejos en elementos más manejables de manera cognitiva. En particular, las decisiones estructuradas tienen el potencial de mejorar la calidad, el rigor y la transparencia de las decisiones sobre las enfermedades de la fauna en una variedad de sistemas. Ejemplos como el manejo del coronavirus del síndrome de respiración agudo tipo 2, el síndrome de nariz blanca, la influenza aviar y la quitridiomicosis ilustran los impedimentos más comunes para la toma de decisiones, incluyendo los objetivos en competencia, riesgos, incertidumbre en las predicciones y recursos limitados.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38569884

RESUMEN

OBJECTIVES: Extended septal myectomy and alcohol septal ablation are 2 invasive treatments for hypertrophic obstructive cardiomyopathy. Our goal was to compare which of these techniques achieved a higher reduction in gradients, improvement in New York Heart Association (NYHA) functional class and reduction in medical treatment. METHODS: It is a single-centre observational and retrospective analysis. We used multivariable regression analyses to assess the association of ablation/myectomy with different outcomes. The odds ratio or coefficient along with the 95% confidence interval was estimated according to the group and adjusted for the corresponding preprocedural variables and EuroSCORE II. RESULTS: A total of 78 patients underwent septal myectomy, and 25 patients underwent alcohol septal ablation. Basal and Valsalva gradients after myectomy were reduced to a higher degree in comparison to ablation: 21.0 mmHg [P < 0.001, 95% confidence interval -30.7; -11.3], and 34.3 mmHg (P < 0.001, -49.1; -19.5) respectively. Those patients who received a myectomy had a lower probability of having moderate mitral regurgitation (odds ratio = 0.18, P = 0.054). Patients after septal myectomy were more likely to be NYHA functional class I (80.4%), whereas patients after ablation were more likely to be NYHA functional class III (48%). Both groups continued with beta-blocker therapy, but disopyramide could be discontinued after the myectomy in more cases (20%-36% vs 59%-1.3%; P < 0.001), and there was a tendency to discontinue calcium channel blockers (48%-16% vs 15.4-3.8%; P = 0.054). CONCLUSIONS: After adjustment using preprocedural gradients and EuroSCORE II, myectomy achieves greater reduction in left ventricular outflow tract gradients compared to septal ablation.

3.
Biophys J ; 122(24): 4730-4747, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-37978804

RESUMEN

Vascular endothelial cells (ECs) form a semipermeable barrier separating vascular contents from the interstitium, thereby regulating the movement of water and molecular solutes across small intercellular gaps, which are continuously forming and closing. Under inflammatory conditions, however, larger EC gaps form resulting in increased vascular leakiness to circulating fluid, proteins, and cells, which results in organ edema and dysfunction responsible for key pathophysiologic findings in numerous inflammatory disorders. In this study, we extend our earlier work examining the biophysical properties of EC gap formation and now address the role of lamellipodia, thin sheet-like membrane projections from the leading edge, in modulating EC spatial-specific contractile properties and gap closure. Micropillars, fabricated by soft lithography, were utilized to form reproducible paracellular gaps in human lung ECs. Using time-lapse imaging via optical microscopy, rates of EC gap closure and motility were measured with and without EC stimulation with the barrier-enhancing sphingolipid, sphingosine-1-phosphate. Peripheral ruffle formation was ubiquitous during gap closure. Kymographs were generated to quantitatively compare the lamellipodia dynamics of sphingosine-1-phosphate-stimulated and -unstimulated ECs. Utilizing atomic force microscopy, we characterized the viscoelastic behavior of EC lamellipodia. Our results indicate decreased stiffness and increased liquid-like behavior of expanding lamellipodia compared with regions away from the cellular edge (lamella and cell body) during EC gap closure, results in sync with the rapid kinetics of protrusion/retraction motion. We hypothesize this dissipative EC behavior during gap closure is linked to actomyosin cytoskeletal rearrangement and decreased cross-linking during lamellipodia expansion. In summary, these studies of the kinetic and mechanical properties of EC lamellipodia and ruffles at gap boundaries yield insights into the mechanisms of vascular barrier restoration and potentially a model system for examining the druggability of lamellipodial protein targets to enhance vascular barrier integrity.


Asunto(s)
Células Endoteliales , Seudópodos , Humanos , Seudópodos/metabolismo , Lisofosfolípidos/metabolismo , Citoesqueleto/metabolismo , Endotelio Vascular/metabolismo , Células Cultivadas
4.
Evol Appl ; 16(7): 1316-1327, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37492149

RESUMEN

Infectious diseases are a major threat for biodiversity conservation and can exert strong influence on wildlife population dynamics. Understanding the mechanisms driving infection rates and epidemic outcomes requires empirical data on the evolutionary trajectory of pathogens and host selective processes. Phylodynamics is a robust framework to understand the interaction of pathogen evolutionary processes with epidemiological dynamics, providing a powerful tool to evaluate disease control strategies. Tasmanian devils have been threatened by a fatal transmissible cancer, devil facial tumour disease (DFTD), for more than two decades. Here we employ a phylodynamic approach using tumour mitochondrial genomes to assess the role of tumour genetic diversity in epidemiological and population dynamics in a devil population subject to 12 years of intensive monitoring, since the beginning of the epidemic outbreak. DFTD molecular clock estimates of disease introduction mirrored observed estimates in the field, and DFTD genetic diversity was positively correlated with estimates of devil population size. However, prevalence and force of infection were the lowest when devil population size and tumour genetic diversity was the highest. This could be due to either differential virulence or transmissibility in tumour lineages or the development of host defence strategies against infection. Our results support the view that evolutionary processes and epidemiological trade-offs can drive host-pathogen coexistence, even when disease-induced mortality is extremely high. We highlight the importance of integrating pathogen and population evolutionary interactions to better understand long-term epidemic dynamics and evaluating disease control strategies.

5.
Transbound Emerg Dis ; 69(5): e2926-e2942, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35752461

RESUMEN

Micromammals have historically been recognized as highly contentious species in terms of the maintenance and transmission of zoonotic pathogens to humans. Limited information is currently available on the epidemiology and potential public health significance of intestinal eukaryotes in wild micromammals. We examined 490 faecal samples, grouped into 155 pools, obtained from 11 micromammal species captured in 11 Spanish provinces for the presence of DNA from Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi and Blastocystis sp. The presence of Leishmania spp. was investigated in individual spleen samples. All micromammal species investigated harboured infections by at least one eukaryotic parasite, except Apodemus flavicollis, Myodes glareolus, Sorex coronatus and Sciurus vulgaris, but the sample size for these host species was very low. Cryptosporidium spp. was the most prevalent species found (3.7%, 95% confidence interval [CI]: 2.2-5.7), followed by G. duodenalis (2.8%, 95% CI: 1.6-4.6) and E. bieneusi (2.6%, 95% CI: 1.4-4.3). All pooled faecal samples tested negative for Blastocystis sp. Leishmania infantum was identified in 0.41% (95% CI: 0.05-1.46) of the 490 individual spleen samples analysed. Sequence analyses allowed the identification of Cryptosporidium andersoni (5.9%), C. ditrichi (11.7%), C. muris (5.9%), C. parvum (5.9%), C. tyzzeri (5.9%), rat genotypes CR97 (5.9%) and W19 (5.9%), vole genotypes V (11.7%) and VII (5.9%) and Cryptosproridium spp. (35.3%) within Cryptosporidium (n = 17). Known genotypes C (66.7%) and Peru11 (25.0%) and a novel genotype (named MouseSpEb1, 8.3%) were detected within E. bieneusi (n = 12). None of the G. duodenalis-positive samples could be genotyped at the assemblage level. Molecular data indicate that wild micromammals were primarily infected by rodent-adapted species/genotypes of eukaryotic pathogens and thereby have a limited role as a source of human infections. The presence of ruminant-adapted species C. andersoni along with finding C. parvum is indicative of an overlap between domestic/peri-domestic and sylvatic transmission cycles of these agents.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Giardia lamblia , Giardiasis , Microsporidiosis , Parásitos , Enfermedades de los Roedores , Animales , China/epidemiología , Criptosporidiosis/epidemiología , Cryptosporidium/genética , Eucariontes , Heces/parasitología , Genotipo , Giardia lamblia/genética , Giardiasis/epidemiología , Giardiasis/parasitología , Giardiasis/veterinaria , Humanos , Microsporidiosis/epidemiología , Microsporidiosis/veterinaria , Ratas , Roedores , Rumiantes , España/epidemiología
6.
Proc Biol Sci ; 289(1967): 20212452, 2022 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-35078353

RESUMEN

Antarctic polynyas are persistent open water areas which enable early and large seasonal phytoplankton blooms. This high primary productivity, boosted by iron supply from coastal glaciers, attracts organisms from all trophic levels to form a rich and diverse community. How the ecological benefit of polynya productivity is translated to the highest trophic levels remains poorly resolved. We studied 119 southern elephant seals feeding over the Antarctic shelf and demonstrated that: (i) 96% of seals foraging here used polynyas, with individuals spending on average 62% of their time there; (ii) the seals exhibited more area-restricted search behaviour when in polynyas; and (iii) these seals gained more energy (indicated by increased buoyancy from greater fat stores) when inside polynyas. This higher-quality foraging existed even when ice was not present in the study area, indicating that these are important and predictable foraging grounds year-round. Despite these energetic advantages from using polynyas, not all the seals used them extensively. Factors other than food supply may influence an individual's choice in their use of feeding grounds, such as exposure to predation or the probability of being able to return to distant sub-Antarctic breeding sites.


Asunto(s)
Phocidae , Animales , Regiones Antárticas , Cubierta de Hielo , Conducta Predatoria
7.
Langmuir ; 38(1): 100-111, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34968052

RESUMEN

Polymerization enhances the stability of a planar supported lipid bilayer (PSLB) but it also changes its chemical and mechanical properties, attenuates lipid diffusion, and may affect the activity of integral membrane proteins. Mixed bilayers composed of fluid lipids and poly(lipids) may provide an appropriate combination of polymeric stability coupled with the fluidity and elasticity needed to maintain the bioactivity of reconstituted receptors. Previously (Langmuir, 2019, 35, 12483-12491) we showed that binary mixtures of the polymerizable lipid bis-SorbPC and the fluid lipid DPhPC form phase-segregated PSLBs composed of nanoscale fluid and poly(lipid) domains. Here we used atomic force microscopy (AFM) to compare the nanoscale mechanical properties of these binary PSLBs with single-component PSLBs. The elastic (Young's) modulus, area compressibility modulus, and bending modulus of bis-SorbPC PSLBs increased upon polymerization. Before polymerization, breakthrough events at forces below 5 nN were observed, but after polymerization, the AFM tip could not penetrate the PSLB up to an applied force of 20 nN. These results are attributed to the polymeric network in poly(bis-SorbPC), which increases the bilayer stiffness and resists compression and bending. In binary DPhPC/poly(bis-SorbPC) PSLBs, the DPhPC domains are less stiff, more compressible, and are less resistant to rupture and bending compared to pure DPhPC bilayers. These differences are attributed to bis-SorbPC monomers and oligomers present in DPhPC domains that disrupt the packing of DPhPC molecules. In contrast, the poly(bis-SorbPC) domains are stiffer and less compressible relative to pure PSLBs; this difference is attributed to DPhPC filling the nm-scale pores in the polymerized domains that are created during bis-SorbPC polymerization. Thus, incomplete phase segregation increases the stability of poly(bis-SorbPC) but has the opposite, detrimental effect for DPhPC. Overall, these results provide guidance for the design of partially polymerized bilayers for technological uses.


Asunto(s)
Membrana Dobles de Lípidos , Polímeros , Difusión , Microscopía de Fuerza Atómica , Polimerizacion
8.
Cell Mol Bioeng ; 14(6): 597-612, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34900013

RESUMEN

INTRODUCTION: Platelet activation by mechanical means such as shear stress exposure, is a vital driver of thrombotic risk in implantable blood-contacting devices used in the treatment of heart failure. Lipids are essential in platelets activation and have been studied following biochemical activation. However, little is known regarding lipid alterations occurring with mechanical shear-mediated platelet activation. METHODS: Here, we determined if shear-activation of platelets induced lipidome changes that differ from those associated with biochemically-mediated platelet activation. We performed high-resolution lipidomic analysis on purified platelets from four healthy human donors. For each donor, we compared the lipidome of platelets that were non-activated or activated by shear, ADP, or thrombin treatment. RESULTS: We found that shear activation altered cell-associated lipids and led to the release of lipids into the extracellular environment. Shear-activated platelets released 21 phospholipids and sphingomyelins at levels statistically higher than platelets activated by biochemical stimulation. CONCLUSIONS: We conclude that shear-mediated activation of platelets alters the basal platelet lipidome. Further, these alterations differ and are unique in comparison to the lipidome of biochemically activated platelets. Many of the released phospholipids contained an arachidonic acid tail or were phosphatidylserine lipids, which have known procoagulant properties. Our findings suggest that lipids released by shear-activated platelets may contribute to altered thrombosis in patients with implanted cardiovascular therapeutic devices. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12195-021-00692-x.

9.
Animals (Basel) ; 11(3)2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33801164

RESUMEN

Coxiella burnetii, the causal agent of human Q fever and animal Coxiellosis, is a zoonotic infectious bacterium with a complex ecology that results from its ability to replicate in multiple (in)vertebrate host species. Spain notifies the highest number of Q fever cases to the ECDC annually and wildlife plays a relevant role in C. burnetii ecology in the country. However, the whole picture of C. burnetii hosts is incomplete, so this study seeks to better understand the role of micromammals in C. burnetii ecology in the country. Spleen samples from 816 micromammals of 10 species and 130 vaginal swabs from Microtus arvalis were analysed by qPCR to detect C. burnetii infection and shedding, respectively. The 9.7% of the spleen samples were qPCR positive. The highest infection prevalence (10.8%) was found in Microtus arvalis, in which C. burnetii DNA was also detected in 1 of the 130 vaginal swabs (0.8%) analysed. Positive samples were also found in Apodemus sylvaticus (8.7%), Crocidura russula (7.7%) and Rattus rattus (6.4%). Positive samples were genotyped by coupling PCR with reverse line blotting and a genotype II+ strain was identified for the first time in one of the positive samples from M. arvalis, whereas only partial results could be obtained for the rest of the samples. Acute Q fever was diagnosed in one of the researchers that participated in the study, and it was presumably linked to M. arvalis handling. The results of the study are consistent with previous findings suggesting that micromammals can be infected by C. burnetii. Our findings additionally suggest that micromammals may be potential sources to trace back the origin of human Q fever and animal Coxiellosis cases in Europe.

10.
J. oral res. (Impresa) ; 10(2): 1-10, abr. 30, 2021. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1382212

RESUMEN

Objetive: The degenerative diseases of the tempo-romandibular joint (TMJ) are characterized by a progressive destruction of the articular tissues of the condyle and the glenoid fossa. The main aim of this review is to describe the effectiveness of the hyaluronic acid (HA) in the treatment of degenerative diseases of the TMJ in accordance with the available scientific evidence. Material and Methods: A literature search was made in the following databases EBSCO, Pubmed, Cochraneand Trip Database, using the keywords hyaluronic, hyaluronan, NaH, hyaluronate, TMJ, TMD, CMD, craniomandibular, orofacial pain and temporomandibular. There were no date or language restrictions applied. Results: After applying inclusion and exclusion criteria, 14 studies were included in this review (11 randomized controlled clinical trials and 3 non-randomized clinical trials). Conclusion: The studies reported a decrease in pain and improvement in functional parameters after treatment of TMJ osteoarthritis with HA . The use of arthrocentesis associated with the administration of HA provides effects synergistic, reaching a superiority the protocols with multiple injections with respect to those of a single session. The adverse effects related to the injection of HA with or without associated arthrocentesis were minor and transitory.


Resumen: Objetivo: Las enfermedades degenerativas de la articulación temporomandibular (ATM) se caracterizan por una destrucción progresiva de tejidos articulares en el cóndilo y la fosa glenoidea. El objetivo principal de esta revisión es describir la efectividad del uso de ácido hialurónico en el tratamiento de enfermedades degenerativas de la articulación temporomandibular de acuerdo con la evidencia científica disponible. Material y Métodos: Se realizó una búsqueda de la literatura en las bases de datos electrónicas EBSCO, PubMed, Cochrane y Trip Database, utilizando las palabras claves hyaluronic, hyaluronan, NaH, hyaluronate, tmj, tmd, cmd, craniomandibular, orofacial pain y temporomandibular, sin límite de fecha ni de idioma hasta Mayo del año 2020, complementada con una búsqueda retrógrada. Resultados: Con base en los criterios de inclusión y exclusión, 14 estudios fueron incluidos en esta revisión (11 ensayos clínicos controlados aleatorizados y 3 ensayos clínicos controlados no aleatorizados). Conclusión: Los estudios reportaron una disminución del dolor y mejora en los parámetros funcionales luego del tratamiento de osteoartritis de la ATM con AH. El uso de artrocentesis asociada a la administración del AH provee efectos sinérgicos, alcanzando una superioridad los protocolos con múltiples inyecciones con respecto a aquellos de una sola sesión. Los efectos adversos relacionados con la inyección de AH con o sin artrocentesis asociada fueron menores y transitorios.


Asunto(s)
Humanos , Osteoartritis/tratamiento farmacológico , Trastornos de la Articulación Temporomandibular/tratamiento farmacológico , Ácido Hialurónico/administración & dosificación , Dolor Facial , Viscosuplementación , Artrocentesis
11.
Ecol Evol ; 11(4): 1620-1633, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33613994

RESUMEN

Partitioning resources is a key mechanism for avoiding intraspecific competition and maximizing individual energy gain. However, in sexually dimorphic species it is difficult to discern if partitioning is due to competition or the different resource needs of morphologically distinct individuals. In the highly dimorphic southern elephant seal, there are intersexual differences in habitat use; at Iles Kerguelen, males predominantly use shelf waters, while females use deeper oceanic waters. There are equally marked intrasexual differences, with some males using the nearby Kerguelen Plateau, and others using the much more distant Antarctic continental shelf (~2,000 km away). We used this combination of inter and intrasexual behavior to test two hypotheses regarding habitat partitioning in highly dimorphic species. (a) that intersexual differences in habitat use will not appear until the seals diverge in body size and (b) that some habitats have higher rates of energy return than others. In particular, that the Antarctic shelf would provide higher energy returns than the Kerguelen Shelf, to offset the greater cost of travel. We quantified the habitat use of 187 southern elephant seals (102 adult females and 85 subadult males). The seals in the two groups were the same size (~2.4 m) removing the confounding effect of body size. We found that the intersexual differences in habitat use existed before the divergence in body size. Also, we found that the amount of energy gained was the same in all of the major habitats. This suggests that the use of shelf habitats by males is innate, and a trade-off between the need to access the large benthic prey available on shelf waters, against the higher risk of predation there. Intrasexual differences in habitat use are another trade-off; although there are fewer predators on the Antarctic shelf, it is subject to considerable interannual fluctuations in sea-ice extent. In contrast, the Kerguelen Plateau presents more consistent foraging opportunities, but contains higher levels of predation. Habitat partitioning in this highly dimorphic species is therefore the result of complex interplay of life history strategies, environmental conditions and predation pressure.

12.
Biophys J ; 118(11): 2769-2782, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32402244

RESUMEN

Medin, a 50-amino-acid cleavage product of the milk fat globule-EGF factor 8 protein, is one of the most common forms of localized amyloid found in the vasculature of individuals older than 50 years. Medin induces endothelial dysfunction and vascular inflammation, yet despite its prevalence in the human aorta and multiple arterial beds, little is known about the nature of its pathology. Medin oligomers have been implicated in the pathology of aortic aneurysm, aortic dissection, and more recently, vascular dementia. Recent in vitro biomechanical measurements found increased oligomer levels in aneurysm patients with altered aortic wall integrity. Our results suggest an oligomer-mediated toxicity mechanism for medin pathology. Using lipid bilayer electrophysiology, we show that medin oligomers induce ionic membrane permeability by pore formation. Pore activity was primarily observed for preaggregated medin species from the growth-phase and rarely for lag-phase species. Atomic force microscopy (AFM) imaging of medin aggregates at different stages of aggregation revealed the gradual formation of flat domains resembling the morphology of supported lipid bilayers. Transmission electron microscopy images showed the coexistence of compact oligomers, largely consistent with the AFM data, and larger protofibrillar structures. Circular dichroism spectroscopy revealed the presence of largely disordered species and suggested the presence of ß-sheets. This observation and the significantly lower thioflavin T fluorescence emitted by medin aggregates compared to amyloid-ß fibrils, along with the absence of amyloid fibers in the AFM and transmission electron microscopy images, suggest that medin aggregation into pores follows a nonamyloidogenic pathway. In silico modeling by molecular dynamics simulations provides atomic-level structural detail of medin pores with the CNpNC barrel topology and diameters comparable to values estimated from experimental pore conductances.


Asunto(s)
Amiloide , Aorta , Péptidos beta-Amiloides , Humanos , Membrana Dobles de Lípidos , Microscopía de Fuerza Atómica
13.
Sci Rep ; 9(1): 8936, 2019 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-31222003

RESUMEN

Foraging behaviour of marine predators inferred from the analysis of horizontal or vertical movements commonly lack quantitative information about foraging success. Several marine mammal species are known to perform dives where they passively drift in the water column, termed "drift" dives. The drift rate is determined by the animal's buoyancy, which can be used to make inference regarding body condition. Long term dive records retrieved via satellite uplink are often summarized before transmission. This loss of resolution hampers identification of drift dives. Here, we develop a flexible, hierarchically structured approach to identify drift dives and estimate the drift rate from the summarized time-depth profiles that are increasingly available to the global research community. Based on high-resolution dive data from southern elephant seals, we classify dives as drift/non-drift and apply a summarization algorithm. We then (i) automatically generate dive groups based on inflection point ordering using a 'Reverse' Broken-Stick Algorithm, (ii) develop a set of threshold criteria to apply across groups, ensuring non-drift dives are most efficiently rejected, and (iii) finally implement a custom Kalman filter to retain the remaining dives that are within the seals estimated drifting time series. Validation with independent data sets shows our method retains approximately 3% of all dives, of which 88% are true drift dives. The drift rate estimates are unbiased, with the upper 95% quantile of the mean squared error between the daily averaged summarized profiles using our method (SDDR) and the observed daily averaged drift rate (ODDR) being only 0.0015. The trend of the drifting time-series match expectations for capital breeders, showing the lowest body condition commencing foraging trips and a progressive improvement as they remain at sea. Our method offers sufficient resolution to track small changes in body condition at a fine temporal scale. This approach overcomes a long-term challenge for large existing and ongoing data collections, with potential application across other drift diving species. Enabling robust identification of foraging success at sea offers a rare and valuable opportunity for monitoring marine ecosystem productivity in space and time by tracking the success of a top predator.


Asunto(s)
Buceo , Conducta Alimentaria , Phocidae/fisiología , Animales , Femenino , Conducta Predatoria , Reproducibilidad de los Resultados
14.
Bio sci (En linea) ; 2(3): 51-60, 2019. ilus.
Artículo en Español | LIBOCS, LILACS | ID: biblio-1050378

RESUMEN

Sucre ciudad turística que alberga una gran riqueza cultural distribuida en los diferentes museos e instituciones que contienen información de Bolivia como sucede con los Archivos y Biblioteca Nacionales de Bolivia que cuentan con una amplia colección en archivos con documentos que datan desde tiempos de la colonia e incluso libros que conllevan más de mil años de antigüedad cuyas características motivaron la presente investigación que con base en otra desarrollada el 2016 donde se identificaron microorganismos causantes del deterioro en archivos coloniales del Archivo y Biblioteca Nacionales de Bolivia, tiene el objetivo de identificar microorganismos presentes en archivos coloniales del Archivo y Biblioteca Nacionales de Bolivia previamente desinfectados en cámara de gas inerte; la investigación se realizó entre octubre del 2017 y mayo del 2018. Para su desarrollo se adoptó un estudio descriptivo, observacional y de corte transversal tomando como objeto de estudio 20 archivos coloniales ya estudiados que contienen microorganismos degradantes, mismos que fueron previamente desinfectados en la cámara de gas inerte para la toma de muestra y posterior análisis laboratorial destinado a validar la efectividad de la cámara. Se encontró mayor porcentaje de bacterias con relación a los hongos, por lo que la eficacia de cámara de gas inerte es mayor contra los hongos, quedando así validada la cámara. Los resultados alcanzados servirán para proponer alternativas de tratamiento no solo a los archivos sino a todos los documentos contenidos en el Archivo y Bibliotecas Nacionales de Bolivia a fin de preservar nuestra Historia hacia futuras generaciones y no perder nuestra riqueza cultural de Bolivia y el Mundo.


Sucre tourist city that houses a great cultural wealth distributed in the different museums and institutions that contain information from Bolivia as it happens with the National Archives and Library of Bolivia that have an extensive collection in archives with documents dating from colonial times and even books that carry more than a thousand years old whose characteristics motivated the present investigation that based on another one developed in 2016 where microorganisms causing the deterioration in colonial archives of the National Archive and Library of Bolivia were identified, have the objective of identifying microorganisms present in archives Colonial National Archives and Library of Bolivia previously disinfected in inert gas chamber; the investigation was conducted between October 2017 and May 2018 For its development, a descriptive, observational and cross-sectional study was adopted, taking as an object of study 20 colonial archives already studied that contain degrading microorganisms, which were previously disinfected in the inert gas chamber for sampling and subsequent laboratory analysis. to validate the effectiveness of the camera. A higher percentage of bacteria was found in relation to fungi, so the efficiency of the inert gas chamber is higher against fungi, thus validating the chamber. The results achieved will serve to propose treatment alternatives not only to the archives but to all the documents contained in the Archive and National Libraries of Bolivia in order to preserve our History towards future generations and not lose our cultural wealth of Bolivia and the World.


Asunto(s)
Bacterias , Archivo , Gases , Bibliotecas
15.
EMBO Mol Med ; 10(1): 32-47, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29208638

RESUMEN

Alzheimer's disease is a devastating neurodegenerative disease eventually leading to dementia. An effective treatment does not yet exist. Here we show that oral application of the compound anle138b restores hippocampal synaptic and transcriptional plasticity as well as spatial memory in a mouse model for Alzheimer's disease, when given orally before or after the onset of pathology. At the mechanistic level, we provide evidence that anle138b blocks the activity of conducting Aß pores without changing the membrane embedded Aß-oligomer structure. In conclusion, our data suggest that anle138b is a novel and promising compound to treat AD-related pathology that should be investigated further.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Benzodioxoles/uso terapéutico , Hipocampo/efectos de los fármacos , Pirazoles/uso terapéutico , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Péptidos beta-Amiloides/genética , Animales , Benzodioxoles/farmacología , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Hipocampo/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal/efectos de los fármacos , Fenotipo , Pirazoles/farmacología , Memoria Espacial/efectos de los fármacos , Transcriptoma/efectos de los fármacos
16.
ACS Chem Neurosci ; 8(6): 1348-1357, 2017 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-28135799

RESUMEN

Amyloid ß (Aß) oligomers are the predominant toxic species in the pathology of Alzheimer's disease. The prevailing mechanism for toxicity by Aß oligomers includes ionic homeostasis destabilization in neuronal cells by forming ion channels. These channel structures have been previously studied in model lipid bilayers. In order to gain further insight into the interaction of Aß oligomers with natural membrane compositions, we have examined the structures and conductivities of Aß oligomers in a membrane composed of brain total lipid extract (BTLE). We utilized two complementary techniques: atomic force microscopy (AFM) and black lipid membrane (BLM) electrical recording. Our results indicate that Aß1-42 forms ion channel structures in BTLE membranes, accompanied by a heterogeneous population of ionic current fluctuations. Notably, the observed current events generated by Aß1-42 peptides in BTLE membranes possess different characteristics compared to current events generated by the presence of Aß1-42 in model membranes comprising a 1:1 mixture of DOPS and POPE lipids. Oligomers of the truncated Aß fragment Aß17-42 (p3) exhibited similar ion conductivity behavior as Aß1-42 in BTLE membranes. However, the observed macroscopic ion flux across the BTLE membranes induced by Aß1-42 pores was larger than for p3 pores. Our analysis of structure and conductance of oligomeric Aß pores in a natural lipid membrane closely mimics the in vivo cellular environment suggesting that Aß pores could potentially accelerate the loss of ionic homeostasis and cellular abnormalities. Hence, these pore structures may serve as a target for drug development and therapeutic strategies for AD treatment.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Canales Iónicos/metabolismo , Membrana Dobles de Lípidos/metabolismo , Lípidos de la Membrana/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/química , Canales Iónicos/química
17.
Nat Photonics ; 11: 352-355, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29576804

RESUMEN

Ultrasensitive nanomechanical instruments, including the atomic force microscope (AFM)1-4 and optical and magnetic tweezers5-8, have helped shed new light on the complex mechanical environments of biological processes. However, it is difficult to scale down the size of these instruments due to their feedback mechanisms9, which, if overcome, would enable high-density nanomechanical probing inside materials. A variety of molecular force probes including mechanophores10, quantum dots11, fluorescent pairs12,13 and molecular rotors14-16 have been designed to measure intracellular stresses; however, fluorescence-based techniques can have short operating times due to photo-instability and it is still challenging to quantify the forces with high spatial and mechanical resolution. Here, we develop a compact nanofibre optic force transducer (NOFT) that utilizes strong near-field plasmon-dielectric interactions to measure local forces with a sensitivity of <200 fN. The NOFT system is tested by monitoring bacterial motion and heart-cell beating as well as detecting infrasound power in solution.

18.
Actas odontol ; 13(2): 32-39, dic. 2016. ilus
Artículo en Español | LILACS | ID: biblio-834227

RESUMEN

El diseño, la planificación, la ejecución y la obtención de una sonrisa armónica trajo consigo el avance de materiales odontológicos, tanto para el uso clínico como laboratorial, y modificaciones en las técnicas restauradoras estéticas. Los diastemas son espacios entre dientes adyacentes que causan generalmente incomodidad estética al paciente. Los laminados cerámicos constituyen una buena alternativa para ofrecer al paciente una sonrisa funcional y armónica por sus propiedades ópticas excelentes, además de su biocompatibilidad con la estructura dentaria y gingival, estabilidad de color y durabilidad a largo plazo, sin embargo la ejecución del tratamiento con estos materiales implica una planificación previa, el análisis estético a través de fotografías digitales y del diseño de la sonrisa, encerado de diagnóstico, ensayos de mock-up, el conocimiento de las características del material, dominio de la técnica clínica en cuanto a la preparación de la estructura dentaria preservando el tejido sano por medio del desgaste selectivo, además de la técnica de provisionales y del protocolo para la cementación. Este trabajo tiene como objetivo presentar una técnica de tratamiento restaurador indirecto con laminados cerámicos para el cierre de diastemas con la finalidad de armonizar la sonrisa.


The design, planning, performance and getting a harmonious smile brought an advance of Dental Materials, of clinical use and laboratory,and changes in esthetic restorative techniques. Diastemas are spaces between adjacent teeth which usually cause an esthetic discomfort of the patient. Ceramic veneers are a good alternative to offer the patient for a functional and harmonious smile with excellent optical properties. In addition to the biocompatibility with the tooth and gingival structure, color stability and durability of a long term, however, the execution of treatment with these material implications prior planning, aesthetic analysis of a through digital photography and smile Design, waxing diagnosis, Mock-up, Testing model, knowledge of material properties, domain the clinical preparation of tooth structure preserving healthy tissue through selective wear, in addition to the temporary restoration technique and protocol for cementation. This clinical report aims to present a technique of indirect restorative treatment with ceramic veneers for diastema closure in order harmonize smile.


Asunto(s)
Humanos , Femenino , Adulto Joven , Coronas con Frente Estético , Diastema/terapia , Porcelana Dental/uso terapéutico , Estética Dental
19.
Nanoscale ; 8(39): 17102-17107, 2016 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-27714046

RESUMEN

Precise positioning of a plasmonic nanoparticle (NP) near a small dielectric surface is not only necessary for understanding gap-dependent interactions between a metal and dielectric but it is also a critical component in building ultrasensitive molecular rulers and force sensing devices. In this study we investigate the gap-dependent scattering of gold and silver NPs by controllably depositing them on an atomic force microscope (AFM) tip and monitoring their scattering within the evanescent field of a tin dioxide nanofiber waveguide. The enhanced distance-dependent scattering profiles due to plasmon-dielectric coupling effects show similar decays for both gold and silver NPs given the strong dependence of the coupling on the decaying power in the near-field. Experiments and simulations also demonstrate that the NPs attached to the AFM tips act as free NPs, eliminating optical interference typically observed from secondary dielectric substrates. With the ability to reproducibly place individual plasmonic NPs on an AFM tip, and optically monitor near-field plasmon-dielectric coupling effects, this approach allows a wide-variety of light-matter interactions studies to be carried out on other low-dimensional nanomaterials.

20.
Methods Mol Biol ; 1345: 251-68, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26453217

RESUMEN

Aggregation can be studied by a range of methods, experimental and computational. Aggregates form in solution, across solid surfaces, and on and in the membrane, where they may assemble into unregulated leaking ion channels. Experimental probes of ion channel conformations and dynamics are challenging. Atomistic molecular dynamics (MD) simulations are capable of providing insight into structural details of amyloid ion channels in the membrane at a resolution not achievable experimentally. Since data suggest that late stage Alzheimer's disease involves formation of toxic ion channels, MD simulations have been used aiming to gain insight into the channel shapes, morphologies, pore dimensions, conformational heterogeneity, and activity. These can be exploited for drug discovery. Here we describe computational methods to model amyloid ion channels containing the ß-sheet motif at atomic scale and to calculate toxic pore activity in the membrane.


Asunto(s)
Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/química , Biología Computacional/métodos , Canales Iónicos/química , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Humanos , Canales Iónicos/metabolismo , Simulación de Dinámica Molecular , Fragmentos de Péptidos/química , Estructura Secundaria de Proteína
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