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1.
Science ; 380(6640): 55-58, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-37023182

RESUMEN

Multicellular organisms typically develop from a single fertilized egg and therefore consist of clonal cells. We report an extraordinary reproductive system in the yellow crazy ant. Males are chimeras of haploid cells from two divergent lineages: R and W. R cells are overrepresented in the males' somatic tissues, whereas W cells are overrepresented in their sperm. Chimerism occurs when parental nuclei bypass syngamy and divide separately within the same egg. When syngamy takes place, the diploid offspring either develops into a queen when the oocyte is fertilized by an R sperm or into a worker when fertilized by a W sperm. This study reveals a mode of reproduction that may be associated with a conflict between lineages to preferentially enter the germ line.


Asunto(s)
Hormigas , Quimerismo , Reproducción , Animales , Masculino , Hormigas/citología , Hormigas/genética , Hormigas/crecimiento & desarrollo , Diploidia , Semen/citología , Células Germinativas/citología
2.
Science ; 377(6603): 285-291, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35857591

RESUMEN

Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging and spectral data collected during and after retrieval of a sample from Bennu's surface. The sampling event mobilized rocks and dust into a debris plume, excavating a 9-meter-long elliptical crater. This exposed material is darker, spectrally redder, and more abundant in fine particulates than the original surface. The bulk density of the displaced subsurface material was 500 to 700 kilograms per cubic meter, which is about half that of the whole asteroid. Particulates that landed on instrument optics spectrally resemble aqueously altered carbonaceous meteorites. The spacecraft stored 250 ± 101 grams of material, which will be delivered to Earth in 2023.

3.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1128-1136, Sept.-Oct. 2021. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345259

RESUMEN

Constant fishing industry innovations in response to consumer demands for novel, balanced healthy products exhibiting high nutritional value, as well as easy to prepare and ready to consume, have led to the emergence of new technologies. Among them, the development of products based on ground beef and fish mixtures are noteworthy. In this context, the purpose of this study was to develop products from different ground rainbow trout and tilapia fillet ratios, in the form of meatballs and nuggets, determining their proximate composition and physico-chemical, microbiological and toxicological characteristics. The average dry matter percentage of the developed products was 29.20±2.30%, while mineral content was 1.45±0.55%, lipid pulp content, 3.70±0.30% and crude pulp protein, 16.60±2.04%. Total psychotropic counts remained below 102 CFU/g, for standard counting on aerobic microorganism plates. Histamine and sulfur-based compounds were not detected in any of the prepared samples. The purpose of the work proposal was to develop foods and technologies that can serve as standards, allowing for simple handling products that apply ground meat mixtures from different fish species to maintain adequate nutritional indices after processing.(AU)


A constante inovação da indústria pesqueira, em resposta às demandas dos consumidores por novos produtos saudáveis, com alto valor nutritivo, balanceados, de fácil preparo e prontos para consumo, levou ao surgimento de novas tecnologias, entre elas o desenvolvimento de produtos à base de mistura de carne moída de pescado. Nesse contexto, a proposta deste trabalho é desenvolver produtos a partir de carne moída de pescado de truta-arco-íris e tilápia, confeccionando almôndegas e nuggets em diferentes proporções, com determinação da composição centesimal e de suas características físico-químicas, microbiológicas e toxicológicas. A matéria seca percentual média foi de 29,20±2,30%. Teores de matéria mineral nos produtos estão em 1,45±0,55%. Os teores de lipídeos aferidos na polpa foram de 3,70±0,30%, e os níveis de proteína bruta apresentados na polpa de 16,60±2,04%. A contagem de psicrotróficos totais manteve-se abaixo de 102 CFU/g, para contagem padrão em placas de micro-organismos aeróbicos. Nas amostras, não foram detectados níveis de histamina e de compostos à base de enxofre. A proposta de trabalho objetivou, por fim, desenvolver alimentos e tecnologias que possam servir como padrões, permitindo que produtos de manipulação simples e que utilizem misturas de carne moída de diferentes espécies de pescado mantenham índices nutricionais adequados após o processamento.(AU)


Asunto(s)
Animales , Industria Pesquera , Productos Pesqueros , Productos de la Carne , Tilapia , Oncorhynchus mykiss
4.
Nervenarzt ; 91(12): 1115-1121, 2020 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-33034670

RESUMEN

In recent years the intestinal microbiome and its interaction with the brain has aroused a growing interest. The findings gained in the course of this research are of great relevance not only to basic scientists but also to clinicians, as studies suggest an association between an altered microbiome and various somatic (e.g. chronic inflammatory intestinal diseases, obesity and diabetes) as well as psychiatric diseases (e.g. anxiety disorders, depression). In addition to a direct influence of the microbiome on the brain and behavior, various mechanisms seem to be relevant, including altered energy intake from food, hormonal changes, probably increased intestinal permeability as well as inflammatory and immunological processes. Anorexia nervosa (AN) is the third most common chronic disease in adolescence and has the highest mortality rate among all mental disorders. In addition to extremely restrictive eating habits, weight loss and comorbid anxiety and depression symptoms, endocrine changes and an increased autoimmune and inflammatory response are characteristic. Since AN is particularly strongly linked to eating behavior and nutrition, research into the microbiome seems very promising, especially with respect to this disease. This article gives a first insight into the underlying processes that play a role in gut-brain interaction in the context of AN and summarizes the previous empirical findings on this topic. Finally, an outlook on future research and possible implications for the therapeutic practice and treatment of AN is given.


Asunto(s)
Anorexia Nerviosa , Microbioma Gastrointestinal , Microbiota , Adolescente , Encéfalo , Conducta Alimentaria , Humanos
5.
Nat Commun ; 11(1): 559, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992705

RESUMEN

Magnetic topological phases of quantum matter are an emerging frontier in physics and material science. Along these lines, several kagome magnets have appeared as the most promising platforms. Here, we explore magnetic correlations in the kagome magnet Co3Sn2S2. Using muon spin-rotation, we present evidence for competing magnetic orders in the kagome lattice of this compound. Our results show that while the sample exhibits an out-of-plane ferromagnetic ground state, an in-plane antiferromagnetic state appears at temperatures above 90 K, eventually attaining a volume fraction of 80% around 170 K, before reaching a non-magnetic state. Strikingly, the reduction of the anomalous Hall conductivity (AHC) above 90 K linearly follows the disappearance of the volume fraction of the ferromagnetic state. We further show that the competition of these magnetic phases is tunable through applying either an external magnetic field or hydrostatic pressure. Our results taken together suggest the thermal and quantum tuning of Berry curvature induced AHC via external tuning of magnetic order.

7.
Nat Astron ; 3(4): 332-340, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31360777

RESUMEN

Early spectral data from the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission reveal evidence for abundant hydrated minerals on the surface of near-Earth asteroid (101955) Bennu in the form of a near-infrared absorption near 2.7 µm and thermal infrared spectral features that are most similar to those of aqueously altered CM carbonaceous chondrites. We observe these spectral features across the surface of Bennu, and there is no evidence of substantial rotational variability at the spatial scales of tens to hundreds of meters observed to date. In the visible and near-infrared (0.4 to 2.4 µm) Bennu's spectrum appears featureless and with a blue (negative) slope, confirming previous ground-based observations. Bennu may represent a class of objects that could have brought volatiles and organic chemistry to Earth.

8.
Risk Anal ; 39(1): 244-256, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-28881443

RESUMEN

When outcomes are defined over a geographic region, measures of spatial risk regarding these outcomes can be more complex than traditional measures of risk. One of the main challenges is the need for a cardinal preference function that incorporates the spatial nature of the outcomes. We explore preference conditions that will yield the existence of spatial measurable value and utility functions, and discuss their application to spatial risk analysis. We also present a simple example on household freshwater usage across regions to demonstrate how such functions can be assessed and applied.

9.
Phys Rev Lett ; 121(6): 067202, 2018 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-30141658

RESUMEN

Determining the fate of the Pauling entropy in the classical spin ice material Dy_{2}Ti_{2}O_{7} with respect to the third law of thermodynamics has become an important test case for understanding the existence and stability of ice-rule states in general. The standard model of spin ice-the dipolar spin ice model-predicts an ordering transition at T≈0.15 K, but recent experiments by Pomaranski et al. suggest an entropy recovery over long timescales at temperatures as high as 0.5 K, much too high to be compatible with the theory. Using neutron scattering and specific heat measurements at low temperatures and with long timescales (0.35 K/10^{6} s and 0.5 K/10^{5} s, respectively) on several isotopically enriched samples, we find no evidence of a reduction of ice-rule correlations or spin entropy. High-resolution simulations of the neutron structure factor show that the spin correlations remain well described by the dipolar spin ice model at all temperatures. Furthermore, by careful consideration of hyperfine contributions, we conclude that the original entropy measurements of Ramirez et al. are, after all, essentially correct: The short-time relaxation method used in that study gives a reasonably accurate estimate of the equilibrium spin ice entropy due to a cancellation of contributions.

10.
J Dent Res ; 97(10): 1152-1159, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29879365

RESUMEN

Transplantation of bone marrow mesenchymal stem cells (BMDCs) into a denervated side of the spinal cord was reported to be a useful option for axonal regeneration. The innervation of teeth is essential for their function and protection but does not occur spontaneously after injury. Cultured reassociations between dissociated embryonic dental mesenchymal and epithelial cells and implantation lead to a vascularized tooth organ regeneration. However, when reassociations were coimplanted with a trigeminal ganglion (TG), innervation did not occur. On the other hand, reassociations between mixed embryonic dental mesenchymal cells and bone marrow-derived cells isolated from green fluorescent protein (GFP) transgenic mice (BMDCs-GFP) (50/50) with an intact and competent dental epithelium (ED14) were innervated. In the present study, we verified the stemness of isolated BMDCs, confirmed their potential role in the innervation of bioengineered teeth, and analyzed the mechanisms by which this innervation can occur. For that purpose, reassociations between mixed embryonic dental mesenchymal cells and BMDCs-GFP with an intact and competent dental epithelium were cultured and coimplanted subcutaneously with a TG for 2 wk in ICR mice. Axons entered the dental pulp and reached the odontoblast layer. BMDCs-GFP were detected at the base of the tooth, with some being present in the pulp associated with the axons. Thus, while having a very limited contribution in tooth formation, they promoted the innervation of the bioengineered teeth. Using quantitative reverse transcription polymerase chain reaction and immunostainings, BMDCs were shown to promote innervation by 2 mechanisms: 1) via immunomodulation by reducing the number of T lymphocytes (CD3+, CD25+) in the implants and 2) by expressing neurotrophic factors such as NGF, BDNF, and NT3 for axonal growth. This strategy using autologous mesenchymal cells coming from bone marrow could be used to innervate bioengineered teeth without treatment with an immunosuppressor such as cyclosporine A (CsA), thus avoiding multiple side effects.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas/métodos , Ingeniería de Tejidos/métodos , Diente/inervación , Animales , Proteínas Fluorescentes Verdes , Células Madre Mesenquimatosas/fisiología , Ratones , Ratones Endogámicos ICR , Ratones Transgénicos , Odontogénesis , Diente/crecimiento & desarrollo
11.
Phys Rev Lett ; 120(13): 137201, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694199

RESUMEN

Excitations in a spin ice behave as magnetic monopoles, and their population and mobility control the dynamics of a spin ice at low temperature. CdEr_{2}Se_{4} is reported to have the Pauling entropy characteristic of a spin ice, but its dynamics are three orders of magnitude faster than the canonical spin ice Dy_{2}Ti_{2}O_{7}. In this Letter we use diffuse neutron scattering to show that both CdEr_{2}Se_{4} and CdEr_{2}S_{4} support a dipolar spin ice state-the host phase for a Coulomb gas of emergent magnetic monopoles. These Coulomb gases have similar parameters to those in Dy_{2}Ti_{2}O_{7}, i.e., dilute and uncorrelated, and so cannot provide three orders faster dynamics through a larger monopole population alone. We investigate the monopole dynamics using ac susceptometry and neutron spin echo spectroscopy, and verify the crystal electric field Hamiltonian of the Er^{3+} ions using inelastic neutron scattering. A quantitative calculation of the monopole hopping rate using our Coulomb gas and crystal electric field parameters shows that the fast dynamics in CdEr_{2}X_{4} (X=Se, S) are primarily due to much faster monopole hopping. Our work suggests that CdEr_{2}X_{4} offer the possibility to study alternative spin ice ground states and dynamics, with equilibration possible at much lower temperatures than the rare earth pyrochlore examples.

12.
Mol Ecol Resour ; 18(4): 778-788, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29573184

RESUMEN

High-throughput sequencing is a powerful tool, but suffers biases and errors that must be accounted for to prevent false biological conclusions. Such errors include batch effects; technical errors only present in subsets of data due to procedural changes within a study. If overlooked and multiple batches of data are combined, spurious biological signals can arise, particularly if batches of data are correlated with biological variables. Batch effects can be minimized through randomization of sample groups across batches. However, in long-term or multiyear studies where data are added incrementally, full randomization is impossible, and batch effects may be a common feature. Here, we present a case study where false signals of selection were detected due to a batch effect in a multiyear study of Alpine ibex (Capra ibex). The batch effect arose because sequencing read length changed over the course of the project and populations were added incrementally to the study, resulting in nonrandom distributions of populations across read lengths. The differences in read length caused small misalignments in a subset of the data, leading to false variant alleles and thus false SNPs. Pronounced allele frequency differences between populations arose at these SNPs because of the correlation between read length and population. This created highly statistically significant, but biologically spurious, signals of selection and false associations between allele frequencies and the environment. We highlight the risk of batch effects and discuss strategies to reduce the impacts of batch effects in multiyear high-throughput sequencing studies.


Asunto(s)
Cabras/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Animales , Frecuencia de los Genes , Polimorfismo de Nucleótido Simple , Selección Genética
13.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 238-246, Jan.-Feb. 2018. tab
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-888066

RESUMEN

Na pesca de arrasto, são inúmeras as espécies de peixe capturadas acidentalmente, compostas, em sua maioria, de espécimes de pequeno tamanho e baixo valor comercial, os quais recebem o nome de rejeito de pesca. O presente trabalho teve como objetivo o desenvolvimento de dois produtos, almôndega e quibe de peixe, tendo como matéria- prima espécies consideradas capturas acidentais na modalidade de pesca de arrasto realizada no litoral do Rio de Janeiro. A identificação taxonômica das espécies teve como resultado as espécies pargo (Pagrus pagrus), castanha (Umbrina sp.), olho-de-cão (Priacanthus arenatus), congro-negro (Conger sp.), congro-rosa (Genypterus brasiliensis) e peixe-sapo (Lophius gastrophysus). A matéria seca percentual na polpa foi de 31,20±1,30%, no quibe e na almôndega crus; os valores foram de 37,90±1,10 e 32,10±1,10, respectivamente. Nos produtos assados, os resultados foram 33,40±1,20 para o quibe e 34,20±1,00 para a almôndega. Os teores de cinzas na polpa foram 1,5% para o quibe e a almôndega crus; os valores de cinzas foram de 2,55±0,05 e 1,47±0,05, respectivamente. Para os produtos assados, os resultados foram 1,87±0,05 para o quibe e 1,92±0,05 para a almôndega. Os teores de lipídeos aferidos na polpa foram de 4,80±0,30%. Com relação ao quibe e à almôndega crus, o percentual de lipídeos foi de 4,20±0,80 e 4,20±0,60, respectivamente. Para os produtos assados, foi de 4,50±0,60 para o quibe e 4,40±0,60 para a almôndega. A proteína bruta apresentou, na polpa, um índice de 15,60±1,04%. Com relação ao quibe e à almôndega crus, 17,80±2,16 e 14,90±2,12, respectivamente. Para os produtos assados, 15,10±2,10 em ambos. Os compostos nitrogenados solúveis, formadores do NNP, apresentaram valores de 285mg NNP/100g de polpa de pescado crua, 291mg NNP/100g no quibe cru e 294mg NNP/100g na almôndega crua. Os resultados da contagem total de psicrotróficos mantiveram-se abaixo de log 7,0UFC/g, para contagem padrão em placas de microrganismos aeróbicos. Não foi constatada a presença de coliformes fecais Salmonella e Staphylococcus aureus. Também não foram detectados níveis de histamina e compostos à base de enxofre nas amostras.(AU)


Seafood products represent an important source of proteins and minerals as well as polyunsaturated fatty acids. However, its consumption in Brazil is very low in comparison to other kinds of meat. This may due to lack of skill in its preparation, making immensurable the importance of the search for new ways to market it, such as ready-made or semi-ready to serve products. The trawl fishery method often accidentally captures a variety of species, composed basically of low commercial value and size. Such catches are called "second-hand catch". With this in mind, this paper has as its main objective de development of two products: fish meatball and kibe, using what is considered accidental catches in the trawl fishery industry done on Rio de Janeiro's offshore as the raw material. The taxonomic identification of the species resulted in the species, Red porgy (Pagrus pagrus), Argentine croaker (Umbrina sp.), Atlantic bigeye (Priacanthus arenatus), Black cusk-eel (Conger sp.), Cusk-eel (Genypterus brasiliensis) and Blackfin goosefish (Lophius gastrophysus). The dry material of the raw product was 31.20±1.30%, in the raw meatball and kibbeh the values was 37.90±1.10 and 32.10±1.10, respectively, in the baked product the results was 33.40±1.20 and 34.20±1.00 (kibbeh and meatball). The ash content in the pulp was 1.5%, for the raw kibbeh and meatball, the amounts of ash were 2.55±0.05 and 1.47±0.05, respectively. For baked goods results were 1.87±0.05 for the kibbeh and 1.92±0.05 for the meatball. The measured lipid levels in the pulp was 4.80±0.30%. In respect, raw kibbeh and meatball, the percentage of lipids were 4.20±0.80 and 4.20±0.60, respectively. For baked goods was 4.50±0.60 for the kibbeh and 4.40±0.60 for the meatball. The protein level presented in the raw material was 15.60±1.04%, to the raw kibbeh and meatball was 17.80±2.16 and 14.90±2.12 and for the baked goods 15.10±2.10 both. Soluble nitrogen compounds shows values of 285mg/100g in the raw material, in the kibbeh NNP 291mg/100g and the meatball NNP 294mg/100g. The results of the total count of psychotropic remained below 7.0 log CFU/g, for standard count of aerobic microorganism plates. Fecal coliform bacteria, Salmonella, and Staphylococcus aureus were not present . The levels of histamine and sulfur basic compounds (H2S) were not detected in the samples.(AU)


Asunto(s)
Animales , Industria Pesquera , Peces/clasificación
14.
Nanomedicine ; 13(7): 2231-2240, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28647591

RESUMEN

Chitosan scaffolds of different deacetylation degrees, average molecular weights and concentrations reinforced with silica nanoparticles were prepared for bone tissue regeneration. The resulting nanocomposites showed similar pore sizes (<300 µm) regardless the deacetylation degree and concentration used in their formulation. Their mechanical compression resistance was increased by a 30% with the addition of silica nanoparticles as nanofillers. The biocompatibility of the three-dimensional chitosan scaffolds was confirmed by the Alamar Blue assay in human primary osteoblasts as well as the formation of cell spheroids indicative of their great potential for bone regeneration. In vivo implantation of the scaffolds in a mice calvaria defect model provided substantial evidences of the suitability of these nanocomposites for bone tissue engineering showing a mature and dense collagenous tissue with small foci of mineralization, vascularized areas and the infiltration of osteoblasts and osteoclasts. Nevertheless, mature bone tissue formation was not observed after eight weeks of implantation.


Asunto(s)
Regeneración Ósea , Quitosano/análogos & derivados , Nanocompuestos/química , Osteogénesis , Dióxido de Silicio/química , Andamios del Tejido/química , Animales , Sustitutos de Huesos/química , Células Cultivadas , Humanos , Masculino , Ensayo de Materiales , Ratones Desnudos , Nanocompuestos/ultraestructura , Nanopartículas/química , Nanopartículas/ultraestructura , Osteoblastos/citología , Porosidad , Cráneo/lesiones , Cráneo/fisiología , Ingeniería de Tejidos
16.
Gynecol Obstet Fertil Senol ; 45(6): 359-365, 2017 Jun.
Artículo en Francés | MEDLINE | ID: mdl-28506797

RESUMEN

OBJECTIVES: To investigate prospectively the pattern of the follicular growth and to characterize the COH outcome in terms of oocyte number and maturity in patients with voluminous recurrent benign ovarian tumors with a high surgical risk of significant reduction of the ovarian follicular content. METHODS: The inclusion criteria were: age between 18 and 36, presence of at least one benign ovarian tumor (≥ 5cm) with high risk of recurrence. The fertility preservation cycle was performed at least 3 months after the cyst surgery. The controlled ovarian stimulation was performed after the ovarian reserve was assessed (AMH measurement and sonographic antral follicle count). Triggering was performed by hCG when at least 3 follicles reached 18mm of diameter. Metaphase II oocytes were cryopreserved by the vitrification technique. RESULTS: Twenty-four women with dermoid, endometrioma or seromucinous cysts were included from January 2015 to July 2016. All of them had previous ovarian surgery. Mean AMH levels were 15.3pmol/L. The mean number of total oocytes retrieved was 7±5. The mean number of metaphase II oocytes was 4.4±4. The incidence of low ovarian response was 38%. Among the patients, 86% had less than 8 metaphase II oocytes vitrified. Seven patients asked for a second cycle in order to have more oocytes. CONCLUSION: We demonstrated the feasibility of the systematic proposal of fertility preservation by oocyte cryopreservation in this group of young patients with recurrent ovarian benign tumors. Taking into account history of previous surgery and high incidence of low ovarian reserve, the ovarian response under stimulation was frequently poor with, as consequence, low retrieved oocyte number per cycle. An oocyte accumulation strategy is then proposed to enhance further pregnancy chances.


Asunto(s)
Criopreservación , Preservación de la Fertilidad/métodos , Recurrencia Local de Neoplasia/cirugía , Oocitos/fisiología , Neoplasias Ováricas/cirugía , Adolescente , Adulto , Femenino , Humanos , Recuperación del Oocito , Oocitos/citología , Folículo Ovárico/patología , Neoplasias Ováricas/patología , Reserva Ovárica , Inducción de la Ovulación/métodos
17.
Proc Biol Sci ; 284(1853)2017 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-28446699

RESUMEN

Collective foraging confers benefits in terms of reduced predation risk and access to social information, but it heightens local competition when resources are limited. In social insects, resource limitation has been suggested as a possible cause for the typical decrease in per capita productivity observed with increasing colony size, a phenomenon known as Michener's paradox. Polydomy (distribution of a colony's brood and workers across multiple nests) is believed to help circumvent this paradox through its positive effect on foraging efficiency, but there is still little supporting evidence for this hypothesis. Here, we show experimentally that polydomy enhances the foraging performance of food-deprived Temnothorax nylanderi ant colonies via several mechanisms. First, polydomy influences task allocation within colonies, resulting in faster retrieval of protein resources. Second, communication between sister nests reduces search times for far away resources. Third, colonies move queens, brood and workers across available nest sites in response to spatial heterogeneities in protein and carbohydrate resources. This suggests that polydomy represents a flexible mechanism for space occupancy, helping ant colonies adjust to the environment.


Asunto(s)
Hormigas/fisiología , Conducta Apetitiva , Conducta Social , Animales , Femenino , Alimentos , Conducta Predatoria
19.
Mucosal Immunol ; 10(4): 1056-1068, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28051086

RESUMEN

Traditionally regarded as simple foot soldiers of the innate immune response limited to the eradication of pathogens, neutrophils recently emerged as more complex cells endowed with a set of immunoregulatory functions. Using a model of invasive pneumococcal disease, we highlighted an unexpected key role for neutrophils as accessory cells in innate interleukin (IL)-17A production by lung resident Vγ6Vδ1+ T cells via nucleotide-binding oligomerization domain receptor, pyrin-containing 3 (NLRP3) inflammasome-dependent IL-1ß secretion. In vivo activation of the NLRP3 inflammasome in neutrophils required both host-derived and bacterial-derived signals. Elaborately, it relies on (i) alveolar macrophage-secreted TNF-α for priming and (ii) subsequent exposure to bacterial pneumolysin for activation. Interestingly, this mechanism can be translated to human neutrophils. Our work revealed the cellular and molecular dynamic events leading to γδT17 cell activation, and highlighted for the first time the existence of a fully functional NLRP3 inflammasome in lung neutrophils. This immune axis thus regulates the development of a protective host response to respiratory bacterial infections.


Asunto(s)
Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Macrófagos Alveolares/inmunología , Neutrófilos/inmunología , Infecciones Neumocócicas/inmunología , Infecciones del Sistema Respiratorio/inmunología , Streptococcus pneumoniae/inmunología , Células Th17/inmunología , Animales , Proteínas Bacterianas/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Inflamasomas/metabolismo , Interleucina-17/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Estreptolisinas/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
20.
Knee ; 24(1): 9-15, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27836691

RESUMEN

BACKGROUND: The purpose of the study was to evaluate the intra- and inter-observer reliabilities of the Genovese grading on MRI in patients after collagen meniscus substitution. METHODS: 84 MRI images of 74 consecutive patients who underwent partial meniscus substitution using collagen meniscus implant (CMI) were assessed. MRIs were evaluated using the Genovese grading system. Furthermore, meniscal extrusion was assessed. Two observers performed the grading twice, blinded to each other and to the previous results, with a six weeks interval. The inter- and intra-observer reliabilities were assessed using kappa and weighted kappa values. RESULTS: The criterion "morphology/size" showed a weighted kappa value inter-observer reliability of 0.069 (rater 1)/0.352 (rater 2) and intra-observer reliability of 0.170 (1st rating)/0.582 (2nd rating). The criterion "signal intensity" showed a weighted kappa value inter-observer reliability of 0.175/0.284 and intra-observer reliability of 0.294/0.458. The criterion "cartilage lesions" showed a kappa value inter-observer reliability of 0.091/0.525 and intra-observer reliability of 0.409/0.413. The criterion "bone marrow edema" showed a kappa value inter-observer reliability of 0.667/0.808 and intra-observer reliability of 0.702/0.715. The criterion "cartilage lesions" showed a kappa value inter-observer reliability of 0.091/0.525 and intra-observer reliability of 0.409/0.413. Regarding meniscal extrusion kappa values for the inter-observer reliability were 0.625/0.940 and 0.625/0.889 for intra-observer reliability. CONCLUSIONS: Three of the four Genovese grading items showed only slight to moderate inter- and intra-observer reliabilities in evaluating CMI on MRI. Hence, such grading results need to be considered with all due care. Only the criteria "bone marrow edema" and "meniscal extrusion" showed a good agreement for both inter- and intra-observer reliabilities.


Asunto(s)
Colágeno , Artropatías/diagnóstico por imagen , Imagen por Resonancia Magnética , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía , Prótesis e Implantes , Adulto , Femenino , Humanos , Artropatías/etiología , Artropatías/cirugía , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
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