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1.
Proc Biol Sci ; 290(2008): 20231329, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37788706

RESUMEN

Red coralline algae are the deepest living macroalgae, capable of creating spatially complex reefs from the intertidal to 100+ m depth with global ecological and biogeochemical significance. How these algae maintain photosynthetic function under increasingly limiting light intensity and spectral availability is key to explaining their large depth distribution. Here, we investigated the photo- and chromatic acclimation and morphological change of free-living red coralline algae towards mesophotic depths in the Fernando do Noronha archipelago, Brazil. From 13 to 86 m depth, thalli tended to become smaller and less complex. We observed a dominance of the photo-acclimatory response, characterized by an increase in photosynthetic efficiency and a decrease in maximum electron transport rate. Chromatic acclimation was generally stable across the euphotic-mesophotic transition with no clear depth trend. Taxonomic comparisons suggest these photosynthetic strategies are conserved to at least the Order level. Light saturation necessitated the use of photoprotection to 65 m depth, while optimal light levels were met at 86 m. Changes to the light environment (e.g. reduced water clarity) due to human activities therefore places these mesophotic algae at risk of light limitation, necessitating the importance of maintaining good water quality for the conservation and protection of mesophotic habitats.


Asunto(s)
Antozoos , Rhodophyta , Humanos , Animales , Arrecifes de Coral , Ecosistema , Fotosíntesis , Aclimatación , Antozoos/fisiología
2.
Trop Anim Health Prod ; 56(1): 10, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38093117

RESUMEN

The current investigation was conducted to investigate the effects of different particle sizes of corn and stocking densities on performance, carcass traits and gastrointestinal tract (GIT) development of Muscovy ducks in housing. 200 Muscovy ducks were distributed in a factorial scheme (2 × 2) where the treatments were constituted by two stocking densities (2 or 3 birds/m2) and two particle sizes of corn (6 or 8 mm), with five replicates of 10 birds each. At 1, 35, 70, and 90 days old, Muscovy ducks were slaughtered to evaluate the development of heart and GIT. Muscovy ducks managed in the density of 3 birds/m2 presented higher (P < 0.05) GIT development, performance and carcass traits regardless of age evaluated. In the same way, Muscovy ducks fed diets using a particle size of corn of 6 mm (Mean Geometric Diameter (MGD) = 781 µm) presented higher (P < 0.05) GIT development, performance and carcass traits regardless of age evaluated. Conclusively, the stocking density of 3 birds/m2 and the particle size of corn of 6 mm (MGD = 781 µm) were considered ideal recommendations for Muscovy ducks, providing higher GIT development, which resulted in better performance and carcass traits.


Asunto(s)
Patos , Zea mays , Animales , Tamaño de la Partícula , Vivienda , Tracto Gastrointestinal
3.
Proc Biol Sci ; 289(1969): 20211834, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35193402

RESUMEN

The euphotic-mesophotic transition is characterized by dramatic changes in environmental conditions, which can significantly alter the functioning of ecosystem engineers and the structure of their associated communities. However, the drivers of biodiversity change across the euphotic-mesophotic transition remain unclear. Here, we investigated the mechanisms affecting the biodiversity-supporting potential of free-living red coralline algae-globally important habitat creators-towards mesophotic depths. Across a 73 m depth gradient, we observed a general decline in macrofaunal biodiversity (fauna abundance, taxon richness and alpha diversity), but an increase in beta-diversity (i.e. variation between assemblages) at the deepest site (86 m depth, where light levels were less than 1% surface irradiance). We identified a gradient in abundance decline rather than distinct ecological shifts, driven by a complex interaction between declining light availability, declining size of the coralline algal host individuals and a changing host taxonomy. However, despite abundance declines, high between-assemblage variability at deeper depths allowed biodiversity-supporting potential to be maintained, highlighting their importance as coastal refugia.


Asunto(s)
Arrecifes de Coral , Ecosistema , Biodiversidad , Humanos , Fenotipo , Refugio de Fauna
4.
Stereotact Funct Neurosurg ; 99(1): 75-78, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32937630

RESUMEN

BACKGROUND: Balloon compression of the gasserian ganglion has been a well-established percutaneous treatment of trigeminal neuralgia since the 1980s. However, puncture of the foramen ovale by conventional single-plane fluoroscopy can be difficult in cases of local anatomic abnormalities. CASE PRESENTATION: We present the case of a 49-year-old woman diagnosed with idiopathic trigeminal neuralgia refractory to pharmacological treatment. After failure of puncture by conventional fluoroscopy for percutaneous gasserian ganglion balloon compression due to a narrow foramen ovale, the patient was submitted to puncture guided by computed tomography. CONCLUSION: Alternative imaging methods, such as computed tomography, should be considered when puncture of the foramen ovale by conventional single-plane fluoroscopy fails, to minimize the risk of potential complications triggered by frustrated puncture attempts.


Asunto(s)
Fluoroscopía/métodos , Foramen Oval/diagnóstico por imagen , Monitoreo Intraoperatorio/métodos , Punciones/métodos , Tomografía Computarizada por Rayos X/métodos , Neuralgia del Trigémino/diagnóstico por imagen , Femenino , Foramen Oval/cirugía , Humanos , Persona de Mediana Edad , Ganglio del Trigémino/diagnóstico por imagen , Ganglio del Trigémino/cirugía , Neuralgia del Trigémino/cirugía
5.
Sensors (Basel) ; 21(21)2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34770592

RESUMEN

Non-standard diesel blends can be harmful to the environment and human health. In this context, a simple analytical method to estimate the biodiesel mixture ratio in diesel was developed based on impedance spectroscopy (IS) associated with interdigitated sensors. In this article, four different interdigitated sensors with varied comb spacing (G) were simulated using the COMSOL Multiphysics software. Based on finite element simulations, four interdigitated electrode architectures were manufactured and evaluated. The best geometry was chosen according to theoretical data simulations, and its interdigitated electrodes were manufactured for the compositional evaluation of pseudo-binary biodiesel-diesel mixtures. According to the X-ray powder diffraction technique, the deposition of the conductive layer (Au0) over the surface of the dielectric substrate (SiO2) did not alter its phase composition. In the analysis of AFM and SEM, it was possible to observe irregular edges on the electrodes, possibly related to the manufacturing process of the thin layers and mechanical stability. Another characteristic observed in the AFM images was the height of the step of the gold layer of the sensor. Several cross sections were obtained, and the mean step value was 225.71 ± 0.0032 nm. Although there were differences in the roughness, the whole sensor had nanometric roughness. Based on the finite element method simulation performed, it can be assumed that the geometric parameters more suitable for the manufacturing of the electrode are W = 20 µm, L = 1000 µm, G = 50 µm, and N = 40 digits. The electrical characterization performed by impedance spectroscopy showed that we could differentiate between biodiesel and diesel fuels and their pseudo-binary mixtures in the low-frequency region.


Asunto(s)
Biocombustibles , Dióxido de Silicio , Electrodos , Gasolina , Oro , Humanos
6.
Conserv Biol ; 32(5): 1096-1106, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28646574

RESUMEN

Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade-offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat-based approach to estimate the spatial distribution of opportunity cost to fishers in data-poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no-take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade-offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad , Costos y Análisis de Costo , Explotaciones Pesqueras
7.
J Nat Prod ; 81(10): 2296-2300, 2018 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-30281303

RESUMEN

The new pyrrole-imidazole and pyrrole-guanidine alkaloids 4-debromooroidin (1), 4-debromougibohlin (2), 5-debromougibohlin (3), and 5-bromopalau'amine (4), along with the known hymenidin (5) and (+)-monobromoisophakellin (6), have been isolated from a Dictyonella sp. marine sponge, collected at the Amazon River mouth. The bromine-substitution pattern observed for compounds 1, 2 and 4 is unusual among bromopyrrole alkaloids isolated from marine sponges. The 20S proteasome inhibitory activities of compounds 1-6 have been recorded, with 5-bromopalau'amine (4) being the most active in this series.


Asunto(s)
Poríferos/química , Inhibidores de Proteasoma/química , Inhibidores de Proteasoma/farmacología , Pirroles/química , Pirroles/farmacología , Animales , Brasil , Estructura Molecular , Complejo de la Endopetidasa Proteasomal , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética
8.
Chem Biodivers ; 15(9): e1800239, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29963758

RESUMEN

In order to evaluate the chemical diversity of Syzygiella rubricaulis (Nees) Stephani, a species with a disjunct distribution in the neotropical high mountains, a phytochemical study was carried out with samples from 12 different populations of different altitudes from four South American countries. The chemical profiles of lipophilic extracts were analyzed by GC/MS for each population and 50 different compounds were found with the predominance and richness of sesquiterpenes. The majority of the compounds were found only in one population and the total number of substances ranged from 1 to 15 among the populations, but these numbers were not correlated with altitude, and characterize each population as distinct, based on similarity analysis. The qualitative and quantitative variations of metabolites found are a response to different conditions, under which they live, mostly likely altitudinal conditions. Further studies on the quantification of these chemicals may provide information on their ecological roles and importance for the distribution of S. rubricaulis at different altitudes. Despite the known richness of secondary metabolites produced by bryophytes, they are still poorly explored in the context of the ecological expressions.


Asunto(s)
Ecosistema , Hepatophyta/metabolismo , Altitud , Biodiversidad , Cromatografía de Gases y Espectrometría de Masas , Hepatophyta/clasificación , Sesquiterpenos/metabolismo , América del Sur , Clima Tropical
9.
J Phycol ; 53(3): 642-651, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28258584

RESUMEN

Over the past few decades, progress has been made toward understanding the mechanisms of coralline algae mineralization. However, the relationship between the mineral phase and the organic matrix in coralline algae has not yet been thoroughly examined. The aim of this study was to describe the cell wall ultrastructure of Lithothamnion crispatum, a cosmopolitan rhodolith-forming coralline algal species collected near Salvador (Brazil), and examine the relationship between the organic matrix and the nucleation and growth/shape modulation of calcium carbonate crystals. A nanostructured pattern was observed in L. crispatum along the cell walls. At the nanoscale, the crystals from L. crispatum consisted of several single crystallites assembled and associated with organic material. The crystallites in the bulk of the cell wall had a high level of spatial organization. However, the crystals displayed cleavages in the (104) faces after ultrathin sectioning with a microtome. This organism is an important model for biomineralization studies as the crystallographic data do not fit in any of the general biomineralization processes described for other organisms. Biomineralization in L. crispatum is dependent on both the soluble and the insoluble organic matrix, which are involved in the control of mineral formation and organizational patterns through an organic matrix-mediated process. This knowledge concerning the mineral composition and organizational patterns of crystals within the cell walls should be taken into account in future studies of changing ocean conditions as they represent important factors influencing the physico-chemical interactions between rhodoliths and the environment in coralline reefs.


Asunto(s)
Calcificación Fisiológica , Carbonato de Calcio/metabolismo , Rhodophyta/fisiología , Brasil , Pared Celular/fisiología , Pared Celular/ultraestructura , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión
10.
J Phycol ; 53(6): 1294-1304, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28990189

RESUMEN

Approximately half of the Padina (Dictyotales, Phaeophyceae) species mineralize aragonite needles over the adaxial thallus surface, where mineral bands are interspersed with nonmineralized regions along the thallus from the apical to basal end. However, this calcification pattern and the related algal properties are not well understood. Therefore, this work was performed to elucidate a potential role of cell walls in the inhibition/induction of mineralization in the brown alga Padina gymnospora. In a comparison of specific thallus regions, differences were identified in the cellulose distribution, microfibrils arrangement and thickness, distribution and abundance of phenolic substances, and physical differences among the surfaces of the thallus (deformation, adhesion, topography, and nano-rugosity). In vitro mineralization assays indicated that phenolic substances are strong modulators of calcium carbonate crystals growth. In addition, de novo mineralization assays over cell wall surfaces that were used as templates, even without cellular activity, indicated that the cell wall remains a key factor in the induction/inhibition of mineralization. Overall, the current findings indicate a strong correlation between the physico-chemical and structural properties of the cell wall and the alternation pattern of the mineralization bands over the thallus of P. gymnospora.


Asunto(s)
Calcificación Fisiológica , Carbonato de Calcio/metabolismo , Phaeophyceae/fisiología , Brasil , Pared Celular/fisiología , Pared Celular/ultraestructura , Phaeophyceae/ultraestructura
11.
Plant Cell Physiol ; 57(5): 1008-19, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26936789

RESUMEN

We investigated the organelles involved in the biosynthesis of fatty acid (FA) derivatives in the cortical cells of Laurencia translucida (Rhodophyta) and the effect of these compounds as antifouling (AF) agents. A bluish autofluorescence (with emission at 500 nm) within L. translucida cortical cells was observed above the thallus surface via laser scanning confocal microscopy (LSCM). A hexanic extract (HE) from L. translucida was split into two isolated fractions called hydrocarbon (HC) and lipid (LI), which were subjected to HPLC coupled to a fluorescence detector, and the same autofluorescence pattern as observed by LSCM analyses (emission at 500 nm) was revealed in the LI fraction. These fractions were analyzed by gas chromatography-mass spectrometry (GC-MS), which revealed that docosane is the primary constituent of HC, and hexadecanoic acid and cholesterol trimethylsilyl ether are the primary components of LI. Nile red (NR) labeling (lipid fluorochrome) presented a similar cellular localization to that of the autofluorescent molecules. Transmission and scanning electron microscopy (TEM and SEM) revealed vesicle transport processes involving small electron-lucent vesicles, from vacuoles to the inner cell wall. Both fractions (HC and LI) inhibited micro-fouling [HC, lower minimum inhibitory concentration (MIC) values of 0.1 µg ml(-1); LI, lower MIC value of 10 µg ml(-1)]. The results suggested that L. translucida cortical cells can produce FA derivatives (e.g. HCs and FAs) and secrete them to the thallus surface, providing a unique and novel protective mechanism against microfouling colonization in red algae.


Asunto(s)
Ácidos Grasos/metabolismo , Rhodophyta/fisiología , Transporte Biológico , Pared Celular/química , Pared Celular/metabolismo , Exocitosis , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Rhodophyta/química , Vacuolas/metabolismo
12.
Neural Plast ; 2016: 8528934, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26881138

RESUMEN

Leptin, an adipokine synthesized and secreted mainly by the adipose tissue, has multiple effects on the regulation of food intake, energy expenditure, and metabolism. Its recently-approved analogue, metreleptin, has been evaluated in clinical trials for the treatment of patients with leptin deficiency due to mutations in the leptin gene, lipodystrophy syndromes, and hypothalamic amenorrhea. In such patients, leptin replacement therapy has led to changes in brain structure and function in intra- and extrahypothalamic areas, including the hippocampus. Furthermore, in one of those patients, improvements in neurocognitive development have been observed. In addition to this evidence linking leptin to neural plasticity and function, observational studies evaluating leptin-sufficient humans have also demonstrated direct correlation between blood leptin levels and brain volume and inverse associations between circulating leptin and risk for the development of dementia. This review summarizes the evidence in the literature on the role of leptin in neural plasticity (in leptin-deficient and in leptin-sufficient individuals) and its effects on synaptic activity, glutamate receptor trafficking, neuronal morphology, neuronal development and survival, and microglial function.


Asunto(s)
Encéfalo/fisiopatología , Terapia de Reemplazo de Hormonas , Leptina/análogos & derivados , Leptina/deficiencia , Leptina/fisiología , Plasticidad Neuronal , Amenorrea/tratamiento farmacológico , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Femenino , Humanos , Hipotálamo/metabolismo , Hipotálamo/fisiopatología , Leptina/genética , Leptina/uso terapéutico , Lipodistrofia/tratamiento farmacológico , Masculino , Mutación , Resultado del Tratamiento
13.
J Prosthodont ; 25(8): 665-669, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26436821

RESUMEN

PURPOSE: In testing adhesion using shear bond test, a combination of shear and tensile forces occur at the interface, resulting in complex stresses. The jig designs used for this kind of test show variations in published studies, complicating direct comparison between studies. This study evaluated the effect of different jig designs on metal-ceramic bond strength and assessed the stress distribution at the interface using finite element analysis (FEA). MATERIALS AND METHODS: Metal-ceramic (Metal: Ni-Cr, Wiron 99, Bego; Ceramic: Vita Omega 900, Vita) specimens (N = 36) (diameter: 4 mm, veneer thickness: 4 mm; base diameter: 5 mm, thickness: 1 mm) were fabricated and randomly divided into three groups (n = 12 per group) to be tested using one of the following jig designs: (a) chisel (CH) (ISO 11405), (b) steel strip (SS), (c) piston (PI). Metal-ceramic interfaces were loaded under shear until debonding in a universal testing machine (0.5 mm/min). Failure types were evaluated using scanning electron microscopy (SEM). FEA was used to study the stress distribution using different jigs. Metal-ceramic bond strength data (MPa) were analyzed using ANOVA and Tukey's tests (α = 0.05). RESULTS: The jig type significantly affected the bond results (p = 0.0001). PI type of jig presented the highest results (MPa) (p < 0.05) (58.2 ± 14.8), followed by CH (38.7 ± 7.6) and SS jig type (23.3 ± 4.2) (p < 0.05). Failure types were exclusively a combination of cohesive failure in the opaque ceramic and adhesive interface failure. FEA analysis indicated that the SS jig presented slightly more stress formation than with the CH jig. The PI jig presented small stress concentration with more homogeneous force distribution compared to the CH jig where the stress concentrated in the area where the force was applied. CONCLUSION: Metal-ceramic bond strength was affected by the jig design. Accordingly, the results of in vitro studies on metal-ceramic adhesion should be evaluated with caution. CLINICAL SIGNIFICANCE: When adhesion of ceramic materials to metals is evaluated in in vitro studies, it should be noted that the loading jig type affects the results. Clinical observations should report on the location and type of ceramic fractures in metal-ceramic reconstructions so that the most relevant test method can be identified.


Asunto(s)
Cerámica , Recubrimiento Dental Adhesivo , Metales , Porcelana Dental , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Resistencia al Corte , Estrés Mecánico , Propiedades de Superficie
14.
Neuroimmunomodulation ; 22(4): 263-73, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25633245

RESUMEN

OBJECTIVES: Caspase-1 (casp1), a key protease involved in the systemic inflammatory response syndrome (SIRS), controls the brain expression of a set of eight genes: Nos2 and Ptgs2 (nitric oxide synthase 2 and prostaglandin-endoperoxide synthase 2, two inducible enzymes), Cxcl1 and Cxcl10 (C-X-C motif chemokine ligand 1 and ligand 10), Tgtp and Gbp2 (T cell-specific GTPase 1 and guanylate-binding protein 2, two GTPases), Adamts1 (a disintegrin-like and metallopeptidase with thrombospondin type 1 motif, 1, a metalloprotease) and Il1rn (interleukin-1 receptor antagonist). Our objective was to ascertain whether casp1 also controlled the peripheral expression of these genes and, if so, to compare their central versus peripheral patterns of gene expression in immune and endocrine tissues during SIRS. METHODS: Wild-type (wt) and casp1 knockout (casp1(-/-)) mice were injected with either saline or a high dose of endotoxin/lipopolysaccharide (LPS; 800 µg/mice i.p.). Saline-injected mice were immediately euthanized after injection, whereas LPS-injected mice were sacrificed 6 and 12 h after LPS administration. Hippocampal, splenic and adrenal gene expressions were determined by real-time PCR. RESULTS: Overall, casp1(-/-) mice showed a lower inflammatory response than wt mice. The expression levels of powerful proinflammatory factors such as Nos2 and Ptgs2 was reduced in casp1(-/-) mice. Moreover, a hierarchical clustering analysis aimed at studying patterns of gene coexpression revealed large alterations in the hippocampal pattern of casp1(-/-) mice. Surprisingly, the expression of Adamts1 was increased in the hippocampus and adrenals of casp1(-/-) mice. CONCLUSIONS: The resilience of casp1(-/-) mice to SIRS lethality is associated with a lower inflammatory response, loss of hippocampal gene coexpression patterns, and increased hippocampal Adamts1 gene expression. The latter might be beneficial for casp1(-/-) mice, since ADAMTS1 is likely to play a role in neuronal plasticity. The mechanisms described here may help the development of either novel biomarkers or therapeutic targets against SIRS/sepsis.


Asunto(s)
Glándulas Suprarrenales/metabolismo , Caspasa 1/metabolismo , Expresión Génica , Hipocampo/metabolismo , Lipopolisacáridos/farmacología , Síndrome de Respuesta Inflamatoria Sistémica/metabolismo , Animales , Caspasa 1/deficiencia , Caspasa 1/genética , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Bazo/metabolismo , Síndrome de Respuesta Inflamatoria Sistémica/inducido químicamente
15.
J Phycol ; 51(6): 1137-46, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26987008

RESUMEN

The diagnosis of the order Sporolithales is currently restricted to tetrasporangial anatomy. Until recently, there were few reports about gametangial, and more specifically carposporangial material for the Sporolithales. This study provides the first detailed observations of the anatomy of the mature carposporophyte phase from three species of Sporolithales commonly found in rhodolith beds from Brazil: Sporolithon episporum, S. ptychoides, and Sporolithon sp. Using these observations, along with previously published descriptions and illustrations from other representative species in the order, a comparison was made with the other three orders (Corallinales, Hapalidiales, and Rhodogorgonales) of the Corallinophycidae. We amend the diagnosis of the order Sporolithales to include the anatomy of the mature carposporophyte as follows: carposporangial conceptacles that lack a central fusion cell, but instead with numerous, short, one to two-celled, filaments that bear oblong terminal carposporangia that are distributed across the conceptacle chamber floor and walls.

16.
J Phycol ; 51(2): 225-35, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26986518

RESUMEN

This paper has identified, for the first time in a member of the Rhodophyta, a vacuolar organelle containing enzymes that are involved in the mevalonate pathway-an important step in red algal isoprenoid biosynthesis. These organelles were named mevalonosomes (Mev) and were found in the cortical cells (CC) of Plocamium brasiliense, a marine macroalgae that synthesizes several halogenated monoterpenes. P. brasiliense specimens were submitted to a cytochemical analysis of the activity of the 3-hydroxy-3-methylglutaryl-CoA synthase (HMGS). Using transmission electron microscopy (TEM), we confirmed the presence of HMGS activity within the Mev. Because HMGS is necessary for the biosynthesis of halogenated monoterpenes, we isolated a hexanic fraction (HF) rich in halogenated monoterpenes from P. brasiliense that contained a pentachlorinated monoterpene as a major metabolite. Because terpenes are often related to chemical defense, the antifouling (AF) activity of pentachlorinated monoterpene was tested. We found that the settlement of the mussel Perna perna was reduced by HF treatment (2.25 times less than control; 40% and 90% of fouled surface, respectively; P = 0.001; F9,9 = 1.13). The HF (at 10 µg · mL(-1) ) also inhibited three species of fouling microalgae (Chlorarachnion reptans, Cylindrotheca cloisterium, and Exanthemachrysis gayraliae), while at a higher concentration (50 µg · mL(-1) ), it inhibited the bacteria Halomonas marina, Polaribacter irgensii, Pseudoalteromonas elyakovii, Shewanella putrefaciens, and Vibrio aestuarianus. The AF activity of P. brasiliense halogenated monoterpenes and the localization of HMGS activity inside Mev suggest that this cellular structure found in CC may play a role in thallus protection against biofouling.

17.
BMC Clin Pathol ; 15: 13, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26157353

RESUMEN

BACKGROUND: The use of dried blood spot (DBS) sampling is an alternative to traditional venous blood collection, and particularly useful for people living in rural and remote areas, and for those who are infirm, house-bound or time-poor. The objective of this study was to assess whether the measurement of glycated haemoglobin A1c (HbA1c) in DBS samples provided comparative and acceptably precise results. METHODS: Venous and capillary blood samples were collected from 115 adult participants. After proper instruction, each participant punctured his/her own finger and collected capillary blood samples on pieces of a proprietary cellulose filter paper. Each filter paper was subsequently placed inside a breathable envelope, stored at room temperature, and processed on the same day (D0), four (D4), seven (D7) and fourteen (D14) days after collection. HbA1c was measured in duplicates/triplicates in whole venous blood (WB), capillary blood (capDBS) and venous blood placed on the matrix paper (venDBS), by turbidimetric inhibition immunoassay. Intra-assay coefficients of variation (CV) were calculated. DBS values were compared to WB results using linear regression, Bland-Altman plots and cross-validation models. RESULTS: Eleven and 56 patients had type 1 and type 2 diabetes mellitus, respectively. Mean HbA1c levels were 6.22 ± 1.11 % for WB samples (n = 115). The median intra-assay CV was lower than 3 % for WB and capDBS on all days. Results from capDBS and venDBS showed high correlation and agreement to WB results, with narrow 95 % limits of agreement (except for results from D14 samples), as observed in Bland-Altman plots. When capDBS values were applied to equations derived from regression analyses, results approached those of WB values. A cross-validation model showed that capDBS results on D0, D4 and D7 were close to the WB results, with prediction intervals that were narrow enough to be clinically acceptable. CONCLUSIONS: The measurement of HbA1c from DBS samples provided results that were comparable to results from WB samples, if measured up to seven days after collection. Intra-assay coefficients of variation were low, results were in agreement with the gold-standard, and prediction intervals were clinically acceptable. The measurement of HbA1c through DBS sampling may be considered in situations where traditional venipuncture is not available. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ID ACTRN12613000769785.

18.
Pharmacol Rev ; 64(4): 1004-26, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22966039

RESUMEN

The evident limitations of the amyloid theory of the pathogenesis of Alzheimer's disease are increasingly putting alternatives in the spotlight. We argue here that a number of independently developing approaches to therapy-including specific and nonspecific anti-tumor necrosis factor (TNF) agents, apolipoprotein E mimetics, leptin, intranasal insulin, the glucagon-like peptide-1 mimetics and glycogen synthase kinase-3 (GSK-3) antagonists-are all part of an interlocking chain of events. All these approaches inform us that inflammation and thence cerebral insulin resistance constitute the pathway on which to focus for a successful clinical outcome in treating this disease. The key link in this chain presently absent is a recognition by Alzheimer's research community of the long-neglected history of TNF induction of insulin resistance. When this is incorporated into the bigger picture, it becomes evident that the interventions we discuss are not competing alternatives but equally valid approaches to correcting different parts of the same pathway to Alzheimer's disease. These treatments can be expected to be at least additive, and conceivably synergistic, in effect. Thus the inflammation, insulin resistance, GSK-3, and mitochondrial dysfunction hypotheses are not opposing ideas but stages of the same fundamental, overarching, pathway of Alzheimer's disease pathogenesis. The insight this provides into progenitor cells, including those involved in adult neurogenesis, is a key part of this approach. This pathway also has therapeutic implications for other circumstances in which brain TNF is pathologically increased, such as stroke, traumatic brain injury, and the infectious disease encephalopathies.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Resistencia a la Insulina , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Encéfalo/metabolismo , Humanos , Insulina/metabolismo , Estreptozocina/farmacología
19.
Cranio ; 33(3): 206-10, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25200308

RESUMEN

AIMS: The masseter muscle is a common source of referred pain to the temporomandibular joint (TMJ), with a possibility of false positive diagnoses for arthralgia when diagnosed by research diagnostic criteria for temporomandibular disorders (RDC/TMD) clinical examination. The current study investigated the distribution of arthralgia diagnoses among individuals with myofascial pain, with or without pain on masseter palpation. METHODOLOGY: The study was conducted with 255 outpatients. Clinical data and questionnaires were directly entered into software that deploys algorithms based on the diagnostic criteria of the RDC/TMD, and automatically classifies and stores the diagnosis of each patient evaluated. An association between diagnostic subgroups was verified by calculating the odds ratio (OR), and the statistical significance was tested using the Chi-square test. RESULTS: A higher frequency of concordance (about three times greater) between myofascial pain and arthralgia occurred when there was pain on palpation in the region of the ipsilateral masseter muscle, and the association was statistically significant. CONCLUSIONS: The results of this study revealed a threefold increase in the risk for the presence of temporomandibular arthralgia in cases of myofascial pain combined with pain on palpation in the region of the ipsilateral masseter muscle.


Asunto(s)
Artralgia/diagnóstico , Artralgia/fisiopatología , Dolor Facial/diagnóstico , Dolor Facial/fisiopatología , Músculo Masetero/fisiopatología , Trastornos de la Articulación Temporomandibular/diagnóstico , Trastornos de la Articulación Temporomandibular/fisiopatología , Algoritmos , Femenino , Humanos , Masculino , Dimensión del Dolor , Palpación , Encuestas y Cuestionarios
20.
Curr Microbiol ; 68(1): 38-46, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23979060

RESUMEN

We report on the first characterization of the culturable heterotrophic bacteria of the scleractinian Madracis decactis. In addition, we characterized the culturable bacteria associated with the fireworm Hermodice carunculata, observed predating partially bleached coral colonies. Our study was carried out in the remote St. Peter and St. Paul Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil. We constituted a 403 isolates collection and subsequently characterized it by means of pyrH and 16S rRNA partial sequences. We identified Photobacterium, Bacillus, and Vibrio species as members of the culturable microbiota of healthy M. decactis. V. campbellii, V. harveyi, V. communis, and V. maritimus were the most commonly found Vibrio species in healthy corals, representing more than 60 % of all vibrio isolates. Most of the vibrios isolated from the fireworm's tissues (n = 143; >90 %) were identified as V. shiloi. However, we did not recover V. shiloi from bleached M. decactis. Instead, we isolated V. communis, a novel Photobacterium species, Bacillus, Kocuria, and Pseudovibrio, suggesting a possible role of other facultative anaerobic bacteria and/or environmental features (such as water quality) in the onset of bleaching in SPSPA's M. decactis.


Asunto(s)
Antozoos/microbiología , Bacterias/clasificación , Bacterias/aislamiento & purificación , Poliquetos/microbiología , Animales , Artemia/microbiología , Artemia/fisiología , Brasil , Filogenia , Vibrio/clasificación , Vibrio/aislamiento & purificación , Vibrio/patogenicidad
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