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1.
bioRxiv ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38585801

RESUMEN

The canonical microcircuit (CMC) has been hypothesized to be the fundamental unit of information processing in cortex. Each CMC unit is thought to be an interconnected column of neurons with specific connections between excitatory and inhibitory neurons across layers. Recently, we identified a conserved spectrolaminar motif of oscillatory activity across the primate cortex that may be the physiological consequence of the CMC. The spectrolaminar motif consists of local field potential (LFP) gamma-band power (40-150 Hz) peaking in superficial layers 2 and 3 and alpha/beta-band power (8-30 Hz) peaking in deep layers 5 and 6. Here, we investigate whether specific conserved cell types may produce the spectrolaminar motif. We collected laminar histological and electrophysiological data in 11 distinct cortical areas spanning the visual hierarchy: V1, V2, V3, V4, TEO, MT, MST, LIP, 8A/FEF, PMD, and LPFC (area 46), and anatomical data in DP and 7A. We stained representative slices for the three main inhibitory subtypes, Parvalbumin (PV), Calbindin (CB), and Calretinin (CR) positive neurons, as well as pyramidal cells marked with Neurogranin (NRGN). We found a conserved laminar structure of PV, CB, CR, and pyramidal cells. We also found a consistent relationship between the laminar distribution of inhibitory subtypes with power in the local field potential. PV interneuron density positively correlated with gamma (40-150 Hz) power. CR and CB density negatively correlated with alpha (8-12 Hz) and beta (13-30 Hz) oscillations. The conserved, layer-specific pattern of inhibition and excitation across layers is therefore likely the anatomical substrate of the spectrolaminar motif. Significance Statement: Neuronal oscillations emerge as an interplay between excitatory and inhibitory neurons and underlie cognitive functions and conscious states. These oscillations have distinct expression patterns across cortical layers. Does cellular anatomy enable these oscillations to emerge in specific cortical layers? We present a comprehensive analysis of the laminar distribution of the three main inhibitory cell types in primate cortex (Parvalbumin, Calbindin, and Calretinin positive) and excitatory pyramidal cells. We found a canonical relationship between the laminar anatomy and electrophysiology in 11 distinct primate areas spanning from primary visual to prefrontal cortex. The laminar anatomy explained the expression patterns of neuronal oscillations in different frequencies. Our work provides insight into the cortex-wide cellular mechanisms that generate neuronal oscillations in primates.

2.
Nat Prod Res ; 37(4): 618-627, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35514129

RESUMEN

Fungal resistance to different therapeutic drugs has become a growing challenge. This crucial health problem requires new effective drug alternatives. Herein, we report the study of Eucalyptus botryoides' resin used in folk medicine as antimicrobial. Thus, E. botryoides' resin was extracted with aqueous-ethanol and fractionated using Sephadex chromatography, furnishing its major compounds. The crude extracts and the isolated compounds were evaluated for their in vitro antimicrobial activity against bacteria and yeasts. The crude extract displayed MIC of 25 µg/mL against S. salivarius, and for C. albicans, C. glabrata, and C. tropicalis the MIC were between 2.9 and 5.9 µg/mL. The 7-O-Methyl-aromadendrin was the most effective against C. glabrata and C. krusei (MIC = 1.6 µg/mL). 2-O-Galloyl-1,6-O-di-trans-p-coumaroyl-ß-D-glycopyranoside, first time reported, showed MIC of 3.1 µg/mL against C. glabrata and C. krusei. Overall, this work gave promising results, indicating that Eucalyptus botryoides' resin and its compounds have the potential for developing anti-yeast products.


Asunto(s)
Antiinfecciosos , Eucalyptus , Extractos Vegetales/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Bacterias , Levaduras , Pruebas de Sensibilidad Microbiana , Antifúngicos/química
3.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1047-1057, Sept.-Oct. 2021. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345276

RESUMEN

Colostrum is the main source of immunoglobulins (Ig) for neonate piglets and plays a crucial role within the health and growth of the piglet. Currently in pig farming, there are still no widespread practical methods for measuring the Ig concentration in colostrum at herd level. We evaluated sows' colostrum IgG concentration using an optical and a digital Brix refractometer and their performance was correlated to an IgG ELISA test, and flow cytometry. Colostrum concentrations of IgG and IgA averaged 74.05 ± 21.37mg/mL and 20.2 ± 5.32mg/mL respectively. The mean value of the Brix percentages for optical refractometer was 26.32%, and for digital was 28.32%. The Brix refractometer measurements of colostrum samples presented high correlation for IgG content analyzed by ELISA (Optical = 0.74, Digital = 0.87; P <0.001). Considering the immunophenotyping, the values for IgG and IgA lymphoblasts indicated a highly significant relationship to ELISA (IgG=0.77, IgA=0.84; P<0.001). The Brix refractometer can be considered a useful tool to be included in a colostrum monitoring program to improve potentially neonatal health. In addition, we demonstrated that flow cytometry can be an important tool to analyze and characterize the immunological potential of sow colostrum.(AU)


O colostro é a principal fonte de imunoglobulinas (Ig) para leitões recém-nascidos e desempenha um papel crucial na saúde e no crescimento dos leitões. Atualmente, na suinocultura, ainda não existem métodos amplamente utilizados na prática de produção para medir a concentração de imunoglobulinas no colostro suíno. Avaliou-se a concentração de IgG no colostro de porcas usando refratômetros Brix óptico e digital, e o desempenho foi comparado com ELISA e citometria de fluxo. As concentrações de IgG e IgA no colostro foram 74,05 ± 21,37mg/mL e 20,2 ± 5,32mg/mL, respectivamente. A percentagem de Brix média das amostras de colostro para o refratômetro óptico foi 26,32%, e para o digital foi 28,32%. As medições dos refratômetros de Brix apresentaram elevada correlação com a concentrações de IgG medidas por ELISA (óptico=0,74, digital=0,87; P<0,001). Considerando a imunofenotipagem, os valores dos linfoblastos IgG e IgA apresentaram alta correlação com o ELISA (IgG=0,77, IgA=0,84; P<0,001). O refratômetro Brix pode ser considerado uma ferramenta útil para ser incluída em um programa de monitoramento de colostro para melhorar a saúde neonatal. Além disso, foi demonstrado que a citometria de fluxo pode ser uma ferramenta importante para analisar e caracterizar o potencial imunológico do colostro de porcas.(AU)


Asunto(s)
Animales , Femenino , Embarazo , Inmunoglobulina G , Calostro , Sus scrofa/inmunología , Inmunoglobulina A , Citometría de Flujo/veterinaria
4.
AJNR Am J Neuroradiol ; 42(10): 1822-1826, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34413065

RESUMEN

BACKGROUND AND PURPOSE: The development of flow diverters has changed the endovascular approach to intracranial aneurysms. On the basis of good results, the indications for flow diverters have expanded to include aneurysms of different shapes, locations, and sizes. The objective of the study was to report on the performance of the Flow Re-Direction Endoluminal Device (FRED) in intracranial aneurysm treatment at early and medium-term follow-up. MATERIALS AND METHODS: This single-arm, multicentric, prospective, observational study assessed aneurysm treatment with the FRED. The primary outcome was complete aneurysm occlusion at 6 and 12 months, and the secondary outcome was to evaluate the safety of the FRED with respect to stroke and death rates. RESULTS: Between June 2016 and August 2018, a total of 100 consecutive patients with 131 aneurysms were treated in 107 procedures. Total occlusion rates were 91% and 95% at 6 and 12 months. There was 1 death, and the total final morbidity rate was 1.8%. The complication rate was 4.6%. CONCLUSIONS: As reported previously, the FRED has proved to be a safe and effective tool, with high occlusion rates. The design of the stent makes it more difficult to perform balloon angioplasty compared with similar devices. A branch arising from the aneurysm sac was found to be a predictor of nonocclusion at 12 months, though larger series are needed to estimate the magnitude of the association.


Asunto(s)
Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Estudios de Seguimiento , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/terapia , Estudios Prospectivos , Sistema de Registros , Stents , Resultado del Tratamiento
5.
Braz J Med Biol Res ; 54(10): e11026, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34287580

RESUMEN

Gender equity is far from being achieved in most academic institutions worldwide. Women representation in scientific leadership faces multiple obstacles. Implicit bias and stereotype threat are considered important driving forces concerning gender disparities. Negative cultural stereotypes of weak scientific performance, unrelated to true capacity, are implicitly associated with women and other social groups, influencing, without awareness, attitudes and judgments towards them. Meetings of scientific societies are the forum in which members from all stages of scientific careers are brought together. Visibility in the scientific community stems partly from presenting research as a speaker. Here, we investigated gender disparities in the Brazilian Society of Neuroscience and Behavior (SBNeC). Across the 15 mandates (1978-2020), women occupied 30% of the directory board posts, and only twice was a woman president. We evaluated six meetings held between 2010 and 2019. During this period, the membership of women outnumbered that of men in all categories. A total of 57.50% of faculty members, representing the potential pool of speakers and chairs, were female. Compared to this expected value, female speakers across the six meetings were scarce in full conferences (χ2(5)=173.54, P<0.001) and low in symposia (χ2(5)=36.92, P<0.001). Additionally, women chaired fewer symposia (χ2(5)=47.83, P<0.001). Furthermore, men-chaired symposia had significantly fewer women speakers than women-chaired symposia (χ2(1)=56.44, P<0.001). The gender disparities observed here are similar to those in other scientific societies worldwide, urging them to lead actions to pursue gender balance and diversity. Diversity leads not only to fairness but also to higher-quality science.


Asunto(s)
Equidad de Género , Brasil , Femenino , Humanos , Masculino
6.
J Med Entomol ; 58(3): 1134-1137, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33295966

RESUMEN

The aim of the present study was to describe the morphology of the eggs of Culex (Culex) saltanensis Dyar that occurs in the Neotropical region. Eggs of the Cx. (Cux.) saltanensis were collected at the Mata Atlântica FIOCRUZ campus, fixed in 1% osmium tetroxide, prepared for mounting on metal supports, observed under a scanning electron microscope, and described morphologically. The eggs had a coniform shape with a length of approximately 0.5 mm (505-510 µm) and a width in the median portion of 117 µm (113-123 µm). Upper portion is lined with tubers of irregular shape and varying sizes (0.64-1.31 µm), located on a cross-linked matrix forming bands observed under optical microscopy. The micropyle is encased in a necklace of approximately 6.6-µm plates arranged in a flower-like shape. Comparing Cx. (Cux.) saltanensis eggs with several species of different genera, important divergent characteristics can be observed. However, this study points to the need for new descriptions of eggs of species belonging to the same subgenus in order to analyze if there will be differences between them. Culex (Cux.) saltanensis eggs have particular characteristics not observed in eggs of other Culicidae genera.


Asunto(s)
Culex/ultraestructura , Óvulo/ultraestructura , Animales , Brasil , Culex/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo
7.
Braz. j. med. biol. res ; 54(10): e11026, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1285645

RESUMEN

Gender equity is far from being achieved in most academic institutions worldwide. Women representation in scientific leadership faces multiple obstacles. Implicit bias and stereotype threat are considered important driving forces concerning gender disparities. Negative cultural stereotypes of weak scientific performance, unrelated to true capacity, are implicitly associated with women and other social groups, influencing, without awareness, attitudes and judgments towards them. Meetings of scientific societies are the forum in which members from all stages of scientific careers are brought together. Visibility in the scientific community stems partly from presenting research as a speaker. Here, we investigated gender disparities in the Brazilian Society of Neuroscience and Behavior (SBNeC). Across the 15 mandates (1978-2020), women occupied 30% of the directory board posts, and only twice was a woman president. We evaluated six meetings held between 2010 and 2019. During this period, the membership of women outnumbered that of men in all categories. A total of 57.50% of faculty members, representing the potential pool of speakers and chairs, were female. Compared to this expected value, female speakers across the six meetings were scarce in full conferences (χ2(5)=173.54, P<0.001) and low in symposia (χ2(5)=36.92, P<0.001). Additionally, women chaired fewer symposia (χ2(5)=47.83, P<0.001). Furthermore, men-chaired symposia had significantly fewer women speakers than women-chaired symposia (χ2(1)=56.44, P<0.001). The gender disparities observed here are similar to those in other scientific societies worldwide, urging them to lead actions to pursue gender balance and diversity. Diversity leads not only to fairness but also to higher-quality science.


Asunto(s)
Humanos , Masculino , Femenino , Equidad de Género , Brasil
8.
Philos Trans R Soc Lond B Biol Sci ; 375(1810): 20190507, 2020 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-32892728

RESUMEN

In Europe, three widespread extreme summer drought and heat (DH) events have occurred in 2003, 2010 and 2018. These events were comparable in magnitude but varied in their geographical distribution and biomes affected. In this study, we perform a comparative analysis of the impact of the DH events on ecosystem CO2 fluxes over Europe based on an ensemble of 11 dynamic global vegetation models (DGVMs), and the observation-based FLUXCOM product. We find that all DH events were associated with decreases in net ecosystem productivity (NEP), but the gross summer flux anomalies differ between DGVMs and FLUXCOM. At the annual scale, FLUXCOM and DGVMs indicate close to neutral or above-average land CO2 uptake in DH2003 and DH2018, due to increased productivity in spring and reduced respiration in autumn and winter compensating for less photosynthetic uptake in summer. Most DGVMs estimate lower gross primary production (GPP) sensitivity to soil moisture during extreme summers than FLUXCOM. Finally, we show that the different impacts of the DH events at continental-scale GPP are in part related to differences in vegetation composition of the regions affected and to regional compensating or offsetting effects from climate anomalies beyond the DH centres. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.


Asunto(s)
Dióxido de Carbono/análisis , Cambio Climático , Sequías , Ecosistema , Clima Extremo , Calor , Ciclo del Carbono , Europa (Continente) , Calor Extremo , Modelos Teóricos , Estaciones del Año
9.
Philos Trans R Soc Lond B Biol Sci ; 375(1810): 20190513, 2020 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-32892733

RESUMEN

During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018. Earlier data were retrieved for comparison from international databases or national networks. Here, we show that the usual summer minimum in CO2 due to the surface carbon uptake was reduced by 1.4 ppm in 2018 for the 10 stations located in the area most affected by the temperature anomaly, mostly in Northern Europe. Notwithstanding, the CO2 transition phases before and after July were slower in 2018 compared to 2017, suggesting an extension of the growing season, with either continued CO2 uptake by photosynthesis and/or a reduction in respiration driven by the depletion of substrate for respiration inherited from the previous months due to the drought. For stations with sufficiently long time series, the CO2 anomaly observed in 2018 was compared to previous European droughts in 2003 and 2015. Considering the areas most affected by the temperature anomalies, we found a higher CO2 anomaly in 2003 (+3 ppm averaged over 4 sites), and a smaller anomaly in 2015 (+1 ppm averaged over 11 sites) compared to 2018. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.


Asunto(s)
Atmósfera/análisis , Ciclo del Carbono , Dióxido de Carbono/análisis , Sequías , Ecosistema , Europa (Continente)
10.
Tissue Cell ; 65: 101350, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32746994

RESUMEN

This study aims to provide a histological description of different regions of the gastric and duodenal mucosa in Rhesus monkey, as well as to analyze the distribution and the relative frequency of 5-HT. The cardia region mucosa consists of simple columnar epithelium PAS + and AB + and the 5-HT cells were observed at the base of the gland (QA [5-HT cells]/mm²) = 8.72 ±â€¯4.98). The body region, has a smaller number of glands. The 5-HT cells were found predominant in the base of the gastric glands. QA= 6.96 ±â€¯3.81. When compared to body region, the stomach fundus has smaller gastric pits. The 5-HT cells are found at the base of the glands near the main cells. QA = 5.29 ±â€¯2.09. The pylorus region was found to have deep pits and well-developed gastric glands. The 5-HT cells are scarce, at the base of the pyloric gland. QA = 1.18 ±â€¯1.36. The duodenum presented goblet cells strong PAS + and AB +. 5-HT cells were found both in the lining epithelium and in the intestinal glands. QA = 8.16 ±â€¯2.59.


Asunto(s)
Duodeno/metabolismo , Serotonina/metabolismo , Estómago/fisiología , Animales , Recuento de Células , Duodeno/citología , Macaca mulatta , Masculino , Estómago/citología
11.
Sci Adv ; 6(24): eaba2724, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32577519

RESUMEN

In summer 2018, central and northern Europe were stricken by extreme drought and heat (DH2018). The DH2018 differed from previous events in being preceded by extreme spring warming and brightening, but moderate rainfall deficits, yet registering the fastest transition between wet winter conditions and extreme summer drought. Using 11 vegetation models, we show that spring conditions promoted increased vegetation growth, which, in turn, contributed to fast soil moisture depletion, amplifying the summer drought. We find regional asymmetries in summer ecosystem carbon fluxes: increased (reduced) sink in the northern (southern) areas affected by drought. These asymmetries can be explained by distinct legacy effects of spring growth and of water-use efficiency dynamics mediated by vegetation composition, rather than by distinct ecosystem responses to summer heat/drought. The asymmetries in carbon and water exchanges during spring and summer 2018 suggest that future land-management strategies could influence patterns of summer heat waves and droughts under long-term warming.

12.
Microbiol Resour Announc ; 9(10)2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32139555

RESUMEN

Here, we report the draft genome sequences of three African swine fever viruses isolated from Ornithodoros soft ticks. Isolates LIV 5/40 (Zambia), SPEC 57 (South Africa), and RSA/2/2008 (South Africa) belong to genotypes I, III, and XXII, respectively.

13.
Sci Rep ; 9(1): 17403, 2019 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-31758000

RESUMEN

The chronic unpredictable stress (CUS) paradigm is extensively used in preclinical research. However, CUS exhibits translational inconsistencies, some of them resulting from the use of adult rodents, despite the evidence that vulnerability for many psychiatric disorders accumulates during early life. Here, we assessed the validity of the CUS model by including ethologically-relevant paradigms in juvenile rats. Thus, socially-isolated (SI) rats were submitted to CUS and compared with SI (experiment 1) and group-housed controls (experiment 1 and 2). We found that lower body-weight gain and hyperlocomotion, instead of sucrose consumption and preference, were the best parameters to monitor the progression of CUS, which also affected gene expression and neurotransmitter contents associated with that CUS-related phenotype. The behavioural characterisation after CUS placed locomotion and exploratory activity as the best stress predictors. By employing the exploratory factor analysis, we reduced each behavioural paradigm to few latent variables which clustered into two general domains that strongly predicted the CUS condition: (1) hyper-responsivity to novelty and mild threats, and (2) anxiety/depressive-like response. Altogether, the analyses of observable and latent variables indicate that early-life stress impairs the arousal-inhibition system leading to augmented and persistent responses towards novel, rewarding, and mildly-threatening stimuli, accompanied by lower body-weight gain.


Asunto(s)
Conducta Animal , Estrés Psicológico , Animales , Peso Corporal , Modelos Animales de Enfermedad , Actividad Motora , Ratas , Aislamiento Social , Factores de Tiempo
14.
J Pediatr Urol ; 15(4): 346-352, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31253485

RESUMEN

INTRODUCTION: The use of preoperative topical testosterone stimulation prior to hypospadias correction aims to increase penile size and achieve better surgical results. Topical estradiol has been shown to improve the quality of skin in other sites, but its use in boys with hypospadia has not yet been elucidated. OBJECTIVE: This study aims to evaluate the primary effects in epidermal thickness and collagen distribution of estradiol compared to testosterone and placebo in skin of prepuce before hypospadia surgery. MATHERIALS AND METHODS: Patients were randomized into three groups according to the topical hormone used: TG: Testosterone ointment; EG: Estradiol ointment; CG: Neutral base ointment. Fragments of foreskin were excised, fixed and then sectioned for histology. For each sample, epidermal thickness and dermal collagen expression was measured by specific computer analysis, P-values of <0.05. RESULTS: Thirty-three patients with a mean age of 4.01 ± 2.92 years were included. Hypospadia classification was similar in all three groups. Mean epidermal thickness and collagen type I expression in EG were greater than those of the other groups. Collagen type III expression was similar in all groups. DISCUSSION: Foreskin has a fundamental role in many techniques of hypospadias surgery and can be used either as a graft or a flap in the correction of the penile defect. Increase of epidermal thickness and dermal collagen observed in the present study has already been related to use of estradiol in other skin sites, but not yet in foreskin. Further studies are needed to evaluate the real significance of these findings in boys with hypospadias. CONCLUSION: Use of topical estradiol before hypospadias surgery lead to greater epidermal thickness and increases dermal collagen expression in foreskin.


Asunto(s)
Colágeno/biosíntesis , Estradiol/administración & dosificación , Prepucio/patología , Hipospadias/tratamiento farmacológico , Procedimientos Quirúrgicos Urológicos Masculinos , Administración Tópica , Biopsia , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Epidermis/efectos de los fármacos , Epidermis/metabolismo , Epidermis/patología , Estrógenos/administración & dosificación , Prepucio/efectos de los fármacos , Prepucio/metabolismo , Humanos , Hipospadias/diagnóstico , Hipospadias/cirugía , Lactante , Masculino , Pomadas , Periodo Preoperatorio
15.
ACS Appl Mater Interfaces ; 11(16): 14548-14559, 2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-30943004

RESUMEN

Osteosarcoma is one of the most common metastatic bone cancers, which results in significant morbidity and mortality. Unfolding of effectual therapeutic strategies against osteosarcoma is impeded because of the absence of adequate animal models, which can truly recapitulate disease biology of humans. Tissue engineering provides an opportunity to develop physiologically relevant, reproducible, and tunable in vitro platforms to investigate the interactions of osteosarcoma cells with its microenvironment. Adipose-derived stem cells (ASCs) are detected adjacent to osteosarcoma masses and are considered to have protumor effects. Hence, the present study focuses on investigating the role of reactive ASCs in formation of spheroids of osteosarcoma cells (Saos 2) within a three-dimensional (3D) niche, which is created using gellan gum (GG)-silk fibroin. By modifying the blending ratio of GG-silk, the optimum stiffness of the resultant hydrogels such as GG and GG75: S25 is obtained for cancer spheroid formation. This work indicates that the co-existence of cancer and stem cells can form a spheroid, the hallmark of cancer, only in particular microenvironment stiffness. The incorporation of fibrillar silk fibroin within the hydrophilic network of GG in GG75: S25 spongy-like hydrogels closely mimics the stiffness of commercially established cancer biomaterials (e.g., Matrigel, HyStem). The GG75: S25 hydrogel maintains the metabolically active construct for a longer time with elevated expression of osteopontin, osteocalcin, RUNX 2, and bone sialoprotein genes, the biomarkers of osteosarcoma, compared to GG. The GG75: S25 construct also exhibits intense alkaline phosphatase expression in immunohistochemistry compared to GG, indicating itspotentiality to serve as biomimetic niche to model osteosarcoma. Taken together, the GG-silk fibroin-blended spongy-like hydrogel is envisioned as an alternative low-cost platform for 3D cancer modeling.


Asunto(s)
Adipocitos/metabolismo , Tejido Adiposo/metabolismo , Neoplasias Óseas/metabolismo , Fibroínas/química , Hidrogeles/química , Modelos Biológicos , Osteosarcoma/metabolismo , Esferoides Celulares/metabolismo , Células Madre/metabolismo , Andamios del Tejido/química , Adipocitos/patología , Tejido Adiposo/patología , Neoplasias Óseas/patología , Línea Celular Tumoral , Humanos , Osteosarcoma/patología , Esferoides Celulares/patología , Células Madre/patología , Ingeniería de Tejidos
16.
Ecotoxicol Environ Saf ; 174: 120-128, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30825734

RESUMEN

Despite the increasing interest for biochar as a soil amendment, a knowledge gap remains on its impacts on non-target soil and aquatic species. We hypothesised that biochar particle size and application rate can play a role in the toxicity to biota. Pine woodchip biochar was incorporated in a clean soil at three particle size classes: small (<0.5 mm), medium (1-2 mm), and large (<4 mm), and at two concentrations: 1% and 6% w/w. A laboratory screening with earthworm Eisenia andrei avoidance behaviour bioassay was carried out to test the most adequate application rates, particle sizes and soil-biochar pre-incubation period. Thereafter, a 28-day greenhouse microcosm experiment was conducted as an ecologically more representative approach. Survival, vertical distribution and weight changes of E. andrei, and bait-lamina consumption were recorded. Soil leachates from the microcosms were collected to evaluate their impact on Daphnia magna immobilisation and Vibrio fischeri (Microtox®) bioluminescence. A feeding experiment with E. andrei was also performed to address earthworm weight changes and to conduct a screening of PAH-type metabolites in their tissue. The 6% <0.5 mm treatment pre-incubated for 96 h induced significant avoidance of the earthworms. Significantly lower bait-lamina consumption was observed in microcosms for the 6% <0.5 mm treatment. Moreover, particle size was a statistically significant factor regarding the loss of weight in the feeding experiment and higher concentration of naphthalene-type metabolites detected in E. andrei tissue, when exposed to <0.5 mm biochar particles. The leachates had no adverse effects on the aquatic species. The results suggest that particles <0.5 mm of pine woodchip biochar can pose sub-lethal effects on soil biota.


Asunto(s)
Carbón Orgánico/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Biota , Carbón Orgánico/química , Daphnia/efectos de los fármacos , Tamaño de la Partícula , Suelo , Contaminantes del Suelo/análisis
17.
Virus Genes ; 54(1): 111-123, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29143187

RESUMEN

The central variable region (CVR) within the B602L gene of the African swine fever virus (ASFV) is highly polymorphic within the 23 ASFV genotypes defined by sequencing of the C-terminal end of the p72 locus. Sequencing the p54 gene further discriminates ASFV genotypes that are conserved at the p72 locus. Variation in the thymidine kinase locus is a novel additional tool for ASFV genotyping whose application for this purpose is described for the first time herein. We evaluated genetic variation at these four polymorphic loci in 39 ASFV isolates obtained from outbreaks in Kenya and a region of Eastern Uganda between 2011 and 2013. Analysis of the p72 and p54 loci revealed high genetic conservation among these isolates; all clustered within p72 genotype IX and were similar to isolates associated with earlier outbreaks in East Africa. The thymidine kinase gene of the Kenyan isolates in this study were distinct relative to Southern African isolates and synonymous substitutions were observed among viruses from central Kenya. Analysis of the CVR within the B602L gene revealed two previously unknown polymorphisms that were restricted to Western Kenya and Eastern Uganda. A novel variant was revealed within CVR subgroup XXIV and a novel CVR subgroup XXIVa that contains tetrameric repeat F which has previously only been associated with p72 genotype I, was also identified for the first time in East Africa. Phylogeographic analysis of isolates based on CVR polymorphisms revealed rapid evolution and dissemination of variants present within ASFV genotype IX in East Africa.


Asunto(s)
Virus de la Fiebre Porcina Africana/clasificación , Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/virología , Evolución Molecular , Variación Genética , Tipificación de Secuencias Multilocus , Fiebre Porcina Africana/epidemiología , Virus de la Fiebre Porcina Africana/aislamiento & purificación , Animales , Brotes de Enfermedades , Kenia/epidemiología , Porcinos , Uganda/epidemiología
18.
Braz J Med Biol Res ; 50(11): e5996, 2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28953985

RESUMEN

The objective of this study was to evaluate the relationship between aerobic capacity and pelvic floor muscles (PFM) function in adult women. Women aged 18 or over and without urinary dysfunction or other chronic diseases were eligible to participate. They completed the habitual physical activity (HPA) questionnaire, underwent a PFM functional evaluation by palpation and perineometry, and performed a submaximal (between 75 and 85% of maximum heart rate) cardiopulmonary exercise (CPX) test to determine the ventilatory anaerobic threshold (VAT). Forty-one women were included (35±16 years, 75% physically active, 17% very active, and 8% sedentary and 17% presented grade 1 PFM contraction, 31.8% grade 2, 26.8% grade 3, and 24.4% grade 4, according to the modified Oxford Scale). The average PFM contraction pressure obtained by perineometer was 53±26 cmH2O and the average oxygen consumption at VAT (VO2VAT) obtained from CPX was 14±2 mL·kg-1·min-1. Significant correlations were found between PFM contraction pressure and VO2VAT (r=0.55; P<0.001); between PFM contraction pressure and HPA score (r=0.38; P=0.02); between age and VO2VAT (r=-0.25; P=0.049); and between VO2VAT and HPA score (r=0.36; P=0.02). An age-adjusted multiple linear regression equation (R2=0.32) was derived to estimate VO2VAT from the contraction value obtained by perineometer, so that the PFM contraction pressure was able to predict VO2VAT. The equation was validated using data from another group of 20 healthy women (33±12 years; PFM contraction: 49±23 cmH2O) and no significant difference was found between actual VO2VAT and predicted VO2VAT (13.1±1.9 vs 13.8±2.0 mL·kg-1·min-1). In conclusion, PFM function is associated with aerobic capacity in healthy women and PFM contraction pressure may be used to estimate VO2VAT in this population.


Asunto(s)
Umbral Anaerobio/fisiología , Tolerancia al Ejercicio/fisiología , Ejercicio Físico/fisiología , Músculo Esquelético/fisiología , Adulto , Factores de Edad , Antropometría , Estudios Transversales , Prueba de Esfuerzo , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Contracción Muscular/fisiología , Fuerza Muscular/fisiología , Consumo de Oxígeno/fisiología , Diafragma Pélvico , Presión , Valores de Referencia , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Adulto Joven
19.
Sci Total Environ ; 607-608: 304-316, 2017 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-28692900

RESUMEN

This study focuses on the vertical distribution of total and reactive As in two contrasted coastal sedimentary environments: the Abrolhos Continental Shelf (ACS), a carbonate and siliciclastic shelf sediment, and the Doce River Continental Shelf (DRCS), a submerged delta system. The Doce River was the location of a massive ore tailings dam collapsed in November 2015. Millions of liters of tailings were dumped into the river and reached the continental shelf, causing the country's biggest environmental disaster. We evaluated the As content in sediment of the DRCS before the dam collapse. At both sites, the total As background measured in bottom sediment revealed relative natural enrichment (above 8mg/kg). Content of As decrease with depth; reactive As showed surficial peaks which were associated with Fe and Mn oxides. The ACS sediment did not show significant enrichment or contamination of As, with an enrichment factor (EF) of approximately 2 and a geoaccumulation index (Igeo) near 0. In contrast, the DRCS exhibited severe As enrichment (EF=15) and contamination (Igeo between 3-4). This enrichment is attributed to long-term iron and gold exploitation in the Doce River watershed. The high levels of reactive As, up to 108 mg/kg, alert us to an environmental risk due to potential As bioaccessibility. These data provide an important perspective on the As contamination in continental shelves and encourage the monitoring of the ore mine environmental impacts.

20.
Neurosci Biobehav Rev ; 76(Pt A): 29-38, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28131873

RESUMEN

Violence exacts a burden on public health. Gun violence is a major trigger for motor defensive reactions in humans and post-traumatic stress disorder (PTSD) is its main psychiatric sequela. However, studies of the human defensive cascade, especially the motor reactions, are at an early stage. This review focuses on studies that employ stabilometry, a methodology that assesses whole body motor reactions, to address defensive behaviors to violence-related threats. Special attention is given to three reactions: "attentive immobility", "immobility under attack" and "tonic immobility", with emphasis on the latter - a peritraumatic reaction which has been strongly associated with the severity of PTSD. These reactions are characterized by reduced body sway and bradycardia, except tonic immobility that presents robust tachycardia. The advances made by investigations into the immobility reactions of the human defensive cascade contribute to helping to bridge the gap between human and non-human species. Furthermore, progresses in basic research to objectively monitor motor defensive reactions under threat can help to develop a dimensional, trans-diagnostic approach to PTSD.


Asunto(s)
Mecanismos de Defensa , Trastornos por Estrés Postraumático , Humanos , Pérdida de Tono Postural
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