590 research outputs found
In situ endoscopic analysis of bone microstructure and vascularization in the post-explantation cavities from patients diagnosed with advanced peri-implantitis lesions: A preliminary report.
Morphometric and Histopathologic Changes in Skeletal Muscle Induced for Injectable PLGA Microparticles
Galdames, IS (Galdames, Ivan Suazo).Univ Talca, Talca, ChileThe administration of microencapsulated drug in a matrix acid poly(lactic-co-glycolic acid) (PLGA) by intramuscular (IM) in humans has been approved by the FDA for various applications though it is not clear what effect they have on the morphological parameters of muscle tissue. The aim of this study was to analyze the morphological changes in the skeletal muscle tissue with their use. We used 12 adult female Sprague Dawley rats (Rattus novergicus) that were injected into their right gastrocnemius muscle belly with: sterile vehicle solution (01, n = 4), 0.5 mg PLGA microparticle (02, n = 4) and 0.75 mg PLGA microparticle (03, n = 4), both dissolved in a sterile vehicle solution. At 14 days post injection the number and diameter of muscle fibers, the level of inflammation and histology appearance in terms of organization of muscle fibers, cellular distribution, tissue morphology and the presence of polymer waste were determined and the results between the groups compared. The administration of the compound in a single dose did not alter the morphometric parameters (number and diameter of muscle fibers) despite generating a mild inflammation in the tissue associated with the presence of polymeric residues, suggesting that the PLGA microparticles were well tolerated by the muscle tissue at concentrations tested (0.5 and 0.75 mg).
n Number: WOS:00029366100001
Intellectual synthesis in mentorship determines success in academic careers
As academic careers become more competitive, junior scientists need to understand the value that mentorship brings to their success in academia. Previous research has found that, unsurprisingly, successful mentors tend to train successful students. But what characteristics of this relationship predict success, and how? We analyzed an open-access database of 18,856 researchers who have undergone both graduate and postdoctoral training, compiled across several fields of biomedical science with an emphasis on neuroscience. Our results show that postdoctoral mentors were more instrumental to trainees\u27 success compared to graduate mentors. Trainees\u27 success in academia was also predicted by the degree of intellectual synthesis between their graduate and postdoctoral mentors. Researchers were more likely to succeed if they trained under mentors with disparate expertise and integrated that expertise into their own work. This pattern has held up over at least 40 years, despite fluctuations in the number of students and availability of independent research positions
Distinct Biochemical Pools of Golgi Phosphoprotein 3 in the Human Breast Cancer Cell Lines MCF7 and MDA-MB-231
Golgi phosphoprotein 3 (GOLPH3) has been implicated in the development of carcinomas in many human tissues, and is currently considered a bona fide oncoprotein. Importantly, several tumor types show overexpression of GOLPH3, which is associated with tumor progress and poor prognosis. However, the underlying molecular mechanisms that connect GOLPH3 function with tumorigenicity are poorly understood. Experimental evidence shows that depletion of GOLPH3 abolishes transformation and proliferation of tumor cells in GOLPH3-overexpressing cell lines. Conversely, GOLPH3 overexpression drives transformation of primary cell lines and enhances mouse xenograft tumor growth in vivo. This evidence suggests that overexpression of GOLPH3 could result in distinct features of GOLPH3 in tumor cells compared to that of non-tumorigenic cells. GOLPH3 is a peripheral membrane protein mostly localized at the trans-Golgi network, and its association with Golgi membranes depends on binding to phosphatidylinositol-4-phosphate. GOLPH3 is also contained in a large cytosolic pool that rapidly exchanges with Golgi-associated pools. GOLPH3 has also been observed associated with vesicles and tubules arising from the Golgi, as well as other cellular compartments, and hence it has been implicated in several membrane trafficking events. Whether these and other features are typical to all different types of cells is unknown. Moreover, it remains undetermined how GOLPH3 acts as an oncoprotein at the Golgi. Therefore, to better understand the roles of GOLPH3 in cancer cells, we sought to compare some of its biochemical and cellular properties in the human breast cancer cell lines MCF7 and MDA-MB-231 with that of the non-tumorigenic breast human cell line MCF 10A. We found unexpected differences that support the notion that in different cancer cells, overexpression of GOLPH3 functions in diverse fashions, which may influence specific tumorigenic phenotypes
Using an Ellipsoid Model to Track and Predict the Evolution and Propagation of Coronal Mass Ejections
We present a method for tracking and predicting the propagation and evolution
of coronal mass ejections (CMEs) using the imagers on the STEREO and SOHO
satellites. By empirically modeling the material between the inner core and
leading edge of a CME as an expanding, outward propagating ellipsoid, we track
its evolution in three-dimensional space. Though more complex empirical CME
models have been developed, we examine the accuracy of this relatively simple
geometric model, which incorporates relatively few physical assumptions,
including i) a constant propagation angle and ii) an azimuthally symmetric
structure. Testing our ellipsoid model developed herein on three separate CMEs,
we find that it is an effective tool for predicting the arrival of density
enhancements and the duration of each event near 1 AU. For each CME studied,
the trends in the trajectory, as well as the radial and transverse expansion
are studied from 0 to ~.3 AU to create predictions at 1 AU with an average
accuracy of 2.9 hours.Comment: 18 pages, 11 figure
Optimizing DDRADseq in non-model species: A Case Study in Eucalyptus dunnii Maiden
Restriction site-associated DNA sequencing (RADseq) and its derived protocols, such as double digest RADseq (ddRADseq), offer a flexible and highly cost-effective strategy for efficient plant genome sampling. This has become one of the most popular genotyping approaches for breeding, conservation, and evolution studies in model and non-model plant species. However, universal protocols do not always adapt well to non-model species. Herein, this study reports the development of an optimized and detailed ddRADseq protocol in Eucalyptus dunnii, a non-model species, which combines different aspects of published methodologies. The initial protocol was established using only two samples by selecting the best combination of enzymes and through optimal size selection and simplifying lab procedures. Both single nucleotide polymorphisms (SNPs) and simple sequence repeats (SSRs) were determined with high accuracy after applying stringent bioinformatics settings and quality filters, with and without a reference genome. To scale it up to 24 samples, we added barcoded adapters. We also applied automatic size selection, and therefore obtained an optimal number of loci, the expected SNP locus density, and genome-wide distribution. Reliability and cross-sequencing platform compatibility were verified through dissimilarity coefficients of 0.05 between replicates. To our knowledge, this optimized ddRADseq protocol will allow users to go from the DNA sample to genotyping data in a highly accessible and reproducible way.Instituto de BiotecnologÃaFil: Aguirre, Natalia Cristina. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Filippi, Carla Valeria. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Zaina, Giusi. University of Udine. Department of Agricultural, Food, Environmental and Animal Sciences; ItaliaFil: Rivas, Juan Gabriel. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Acuña, Cintia Vanesa. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Villalba, Pamela Victoria. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Garcia, Martin Nahuel. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Gonzalez, Sergio Alberto. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Rivarola, Maximo Lisandro. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Martinez, Maria Carolina. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Puebla, Andrea Fabiana. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Morgante, Michele. University of Udine. Department of Agricultural, Food, Environmental and Animal Sciences; ItaliaFil: Hopp, Horacio Esteban. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Paniego, Norma Beatriz. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Marcucci Poltri, Susana Noemi. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de BiotecnologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentin
Heliospheric Transport of Neutron-Decay Protons
We report on new simulations of the transport of energetic protons
originating from the decay of energetic neutrons produced in solar flares.
Because the neutrons are fast-moving but insensitive to the solar wind magnetic
field, the decay protons are produced over a wide region of space, and they
should be detectable by current instruments over a broad range of longitudes
for many hours after a sufficiently large gamma-ray flare. Spacecraft closer to
the Sun are expected to see orders-of magnitude higher intensities than those
at the Earth-Sun distance. The current solar cycle should present an excellent
opportunity to observe neutron-decay protons with multiple spacecraft over
different heliographic longitudes and distances from the Sun.Comment: 12 pages, 4 figures, to be published in special issue of Solar
Physic
The impact of socioeconomic and phenotypic traits on self-perception of ethnicity in Latin America
Self-perception of ethnicity is a complex social trait shaped by both, biological and non-biological factors. We developed a comprehensive analysis of ethnic self-perception (ESP) on a large sample of Latin American mestizos from five countries, differing in age, socio-economic and education context, external phenotypic attributes and genetic background. We measured the correlation of ESP against genomic ancestry, and the influence of physical appearance, socio-economic context, and education on the distortion observed between both. Here we show that genomic ancestry is correlated to aspects of physical appearance, which in turn affect the individual ethnic self-perceived ancestry. Also, we observe that, besides the significant correlation among genomic ancestry and ESP, specific physical or socio-economic attributes have a strong impact on self-perception. In addition, the distortion among ESP and genomic ancestry differs across age ranks/countries, probably suggesting the underlying effect of past public policies regarding identity. Our results indicate that individuals’ own ideas about its origins should be taken with caution, especially in aspects of modern life, including access to work, social policies, and public health key decisions such as drug administration, therapy design, and clinical trials, among others
Controlled reduction of photobleaching in DNA origami gold nanoparticle hybrids
The amount of information obtainable from a fluorescence-based measurement is limited by photobleaching: Irreversible photochemical reactions either render the molecules nonfluorescent or shift their absorption and/or emission spectra outside the working range. Photobleaching is evidenced as a decrease of fluorescence intensity with time, or in the case of single molecule measurements, as an abrupt, single-step interruption of the fluorescence emission that determines the end of the experiment. Reducing photobleaching is central for improving fluorescence (functional) imaging, single molecule tracking, and fluorescence-based biosensors and assays. In this single molecule study, we use DNA self-assembly to produce hybrid nanostructures containing individual fluorophores and gold nanoparticles at a controlled separation distance of 8.5 nm. By changing the nanoparticles? size we are able to systematically increase the mean number of photons emitted by the fluorophores before photobleaching.Fil: Pellegrotti, Jesica Vanesa. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de FÃsica; ArgentinaFil: Acuña, Guillermo. Technische Universität Braunschweig. Institute for Physical and Theoretical Chemistry. NanoBioSciences Group; AlemaniaFil: Puchkova, Anastasiya. Technische Universität Braunschweig. Institute for Physical and Theoretical Chemistry. NanoBioSciences Group; AlemaniaFil: Holzmeister, Phil. Technische Universität Braunschweig. Institute for Physical and Theoretical Chemistry. NanoBioSciences Group; AlemaniaFil: Gietl, Andreas. Technische Universität Braunschweig. Institute for Physical and Theoretical Chemistry. NanoBioSciences Group; AlemaniaFil: Lalkens, Birka. Technische Universität Braunschweig. Institute for Physical and Theoretical Chemistry. NanoBioSciences Group; AlemaniaFil: Stefani, Fernando Daniel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de FÃsica; ArgentinaFil: Tinnefeld, Philip. Technische Universität Braunschweig. Institute for Physical and Theoretical Chemistry. NanoBioSciences Group; Alemani
- …