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2.
Braz. j. biol ; 82: e240184, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278492

RESUMO

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.


A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e póscolheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.


Assuntos
Lepidium/genética , Peru , Solo , Microbiologia do Solo , Bactérias/genética , RNA Ribossômico 16S/genética , Pradaria , Metagenômica
3.
Braz. j. biol ; 82: 1-12, 2022. map, ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468535

RESUMO

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.


A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.


Assuntos
Animais , Genes Reporter , Lepidium , Microbiologia do Solo , Regiões Promotoras Genéticas
4.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468722

RESUMO

Abstract Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.


Resumo A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós-colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

5.
Braz J Biol ; 82: e240184, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133559

RESUMO

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.


Assuntos
Lepidium , Bactérias/genética , Pradaria , Lepidium/genética , Metagenômica , Peru , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo
6.
Sci Rep ; 11(1): 9576, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953214

RESUMO

Prokaryotes contribute to the health of marine sponges. However, there is lack of data on the assembly rules of sponge-associated prokaryotic communities, especially for those inhabiting biodiversity hotspots, such as ecoregions between tropical and warm temperate southwestern Atlantic waters. The sympatric species Aplysina caissara, Axinella corrugata, and Dragmacidon reticulatum were collected along with environmental samples from the north coast of São Paulo (Brazil). Overall, 64 prokaryotic phyla were detected; 51 were associated with sponge species, and the dominant were Proteobacteria, Bacteria (unclassified), Cyanobacteria, Crenarchaeota, and Chloroflexi. Around 64% and 89% of the unclassified operational taxonomical units (OTUs) associated with Brazilian sponge species showed a sequence similarity below 97%, with sequences in the Silva and NCBI Type Strain databases, respectively, indicating the presence of a large number of unidentified taxa. The prokaryotic communities were species-specific, ranging 56%-80% of the OTUs and distinct from the environmental samples. Fifty-four lineages were responsible for the differences detected among the categories. Functional prediction demonstrated that Ap. caissara was enriched for energy metabolism and biosynthesis of secondary metabolites, whereas D. reticulatum was enhanced for metabolism of terpenoids and polyketides, as well as xenobiotics' biodegradation and metabolism. This survey revealed a high level of novelty associated with Brazilian sponge species and that distinct members responsible from the differences among Brazilian sponge species could be correlated to the predicted functions.


Assuntos
Poríferos/microbiologia , Células Procarióticas/fisiologia , Simpatria/fisiologia , Animais , Oceano Atlântico , Biodiversidade , Brasil , Filogenia , Água do Mar/microbiologia
8.
Br J Oral Maxillofac Surg ; 58(1): 109-111, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31761568

RESUMO

Intramuscular myxomas are myxoid neoplasms that mainly affect the muscles of the thigh, upper arm, and gluteus. In the head and neck region they are rare, and we know of only two reported cases in the masseter muscle. We think that this is the third. A 60-year-old woman presented with a painless nodule on the right side of her face. Magnetic resonance imaging showed a well-defined mass restricted to the muscle, with no infiltration into adjacent structures. Microscopic analysis confirmed the gross examination, and showed a tumour with copious myxoid stroma, scattered spindle to stellate cells, and an absence of atypia, which did not stain for CD34, S100, or smooth-muscle actin. A final diagnosis of intramuscular myxoma was made. Despite its rarity, it is important to consider this neoplasm in the differential diagnosis of tumours with a gelatinous-like appearance that involve masticatory muscles of the head and neck.


Assuntos
Neoplasias Musculares/diagnóstico , Mixoma/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Músculo Masseter , Pessoa de Meia-Idade , Síndrome
9.
Br J Oral Maxillofac Surg ; 57(5): 479-480, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31054793

RESUMO

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a rare vascular proliferation of unknown pathogenesis that may be related to trauma. Although it affects mainly the head and neck, the zygomatic area is rarely involved. We report a case that affected the zygomatic region of a 46-year-old black man. The lesion had been present for about a year and the patient reported that it appeared after a facial injury during a soccer match. Clinical and tomographic investigations suggested a benign tumour, and the lesion was excised through an intraoral approach. Histopathological examination showed the unexpected diagnosis of ALHE. This tumour was interesting because of its rarity, and also because of its unusual site within the head and neck region. The diagnosis of ALHE is hardly ever considered in the differential diagnosis of zygomatic nodules.


Assuntos
Hiperplasia Angiolinfoide com Eosinofilia/patologia , Zigoma , Hiperplasia Angiolinfoide com Eosinofilia/diagnóstico por imagem , Diagnóstico Diferencial , Hemangioma , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço , Tomografia Computadorizada por Raios X
10.
Osteoporos Int ; 30(5): 1015-1023, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30693381

RESUMO

Although chronic kidney disease is associated with other bone disorders, osteoporosis can be found in this context, and it is defined based on bone mineral density (BMD), measured by dual-energy X-ray absorptiometry. As CKD progresses, the percentage of normal BMD decreases, whereas that of osteopenia/osteoporosis increases, mostly due to hip involvement, particularly in patients with reduced renal function. INTRODUCTION: Osteoporosis is a highly prevalent disease in patients with chronic kidney disease (CKD). We investigated the features of bone mineral density (BMD) in patients with assorted kidney diseases and hypothesized that low BMD, as measured by dual-energy X-ray absorptiometry (DXA), would be more prevalent as kidney function decreased and would correlate with biomarkers of mineral and bone disease. METHODS: DXA obtained from January 1, 2008, to December 31, 2017, clinical, demographic, and biochemical data at the time of image acquisition were recorded. Data from 1172 patients were included in this study (81.3% women, 79.9% white, and 8.1% diabetic). RESULTS: Osteopenia and osteoporosis in at least one site (total hip or spine) were found in 32.7% and 20.0% of patients, respectively. As CKD progressed, the percentage of patients with normal BMD decreased, whereas the percentage of osteopenia and osteoporosis increased, which was mostly due to the total hip involvement, particularly in patients with estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2. Older age and hyperparathyroidism were independent risk factors for osteopenia/osteoporosis at the total hip; female gender, older age, and higher iCa were independently associated with the risk of osteopenia/osteoporosis at the spine. With eGFR > 90 ml/min as reference, the odds ratios for osteoporosis/osteopenia at the hip were 1.51 (95% CI 1.01-2.24) and 1.91 (95% CI 1.13-3.20) for patients with eGFR 30-60 and 15-30 ml/min/1.73 m2, respectively. No CKD stage was significantly associated with the risk of osteoporosis/osteopenia at the spine. CONCLUSION: Our results highlighted that low BMD in patients with CKD is associated with age and hyperparathyroidism, and affects predominantly the hip.


Assuntos
Doenças Ósseas Metabólicas/etiologia , Articulação do Quadril/fisiopatologia , Vértebras Lombares/fisiopatologia , Insuficiência Renal Crônica/complicações , Absorciometria de Fóton , Adulto , Idoso , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/fisiopatologia , Brasil/epidemiologia , Progressão da Doença , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Osteoporose/etiologia , Osteoporose/fisiopatologia , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença
11.
Mar Biotechnol (NY) ; 21(1): 65-75, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30443837

RESUMO

Bone fractures characterize an important event in the medical healthcare, being related to traumas, aging, and diseases. In critical conditions, such as extensive bone loss and osteoporosis, the tissue restoration may be compromised and culminate in a non-union consolidation. In this context, the osteogenic properties of biomaterials with a natural origin have gained prominence. Particularly, marine sponges are promising organisms that can be exploited as biomaterials for bone grafts. Thus, the objectives of this study were to study the physicochemical and morphological properties of biosilica (BS) from sponges by using scanning electron microscopy, Fourier-transform infrared, X-ray diffraction (SEM, FTIR and XRD respectively), mineralization, and pH. In addition, tests on an osteoblast precursor cell line (MC3T3-E1) were performed to investigate its cytotoxicity and proliferation in presence of BS. Bioglass (BG) was used as gold standard material for comparison purposes. Sponge BS was obtained, and this fact was proven by SEM, FTIR, and XRD analysis. Calcium assay showed a progressive release of this ion from day 7 and a more balanced pH for BS was maintained compared to BG. Cytotoxicity assay indicated that BS had a positive influence on MC3T3-E1 cells viability and qRT-PCR showed that this material stimulated Runx2 and BMP4 gene expressions. Taken together, the results indicate a potential use of sponge biosilica for tissue engineering applications.


Assuntos
Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/farmacologia , Osteoblastos/efeitos dos fármacos , Poríferos/química , Dióxido de Silício/farmacologia , Animais , Materiais Biocompatíveis/isolamento & purificação , Biomarcadores/metabolismo , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Substitutos Ósseos/isolamento & purificação , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Fraturas Ósseas/terapia , Expressão Gênica , Humanos , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismo , Dióxido de Silício/isolamento & purificação , Engenharia Tecidual/métodos
12.
Sci Rep ; 7: 43465, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28266549

RESUMO

Interactions between parasite, host and host-associated microbiota are increasingly understood as important determinants of disease progression and morbidity. Salmon lice, including the parasitic copepod Lepeophtheirus salmonis and related species, are perhaps the most important problem facing Atlantic Salmon aquaculture after feed sustainability. Salmon lice parasitize the surface of the fish, feeding off mucus, scales and underlying tissue. Secondary bacterial infections are a major source of associated morbidity. In this study we tracked the diversity and composition of Salmo salar skin surface microbiota throughout a complete L. salmonis infection cycle among 800 post-smolts as compared to healthy controls. Among infected fish we observed a significant reduction in microbial richness (Chao1, P = 0.0136), raised diversity (Shannon, P < 7.86e-06) as well as highly significant destabilisation of microbial community composition (Pairwise Unifrac, beta-diversity, P < 1.86e-05; P = 0.0132) by comparison to controls. While undetectable on an individual level, network analysis of microbial taxa on infected fish revealed the association of multiple pathogenic genera (Vibrio, Flavobacterium, Tenacibaculum, Pseudomonas) with high louse burdens. We discuss our findings in the context of ecological theory and colonisation resistance, in addition to the role microbiota in driving primary and secondary pathology in the host.


Assuntos
Copépodes/patogenicidade , Doenças dos Peixes/parasitologia , Interações Hospedeiro-Parasita , Interações Hospedeiro-Patógeno , Mucosa/parasitologia , Salmo salar/parasitologia , Animais , Aquicultura , Copépodes/fisiologia , Doenças dos Peixes/microbiologia , Flavobacterium/genética , Flavobacterium/crescimento & desenvolvimento , Flavobacterium/patogenicidade , Variação Genética , Humanos , Microbiota/genética , Mucosa/microbiologia , Pseudomonas/genética , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/patogenicidade , Salmo salar/microbiologia , Pele/microbiologia , Pele/parasitologia , Tenacibaculum/genética , Tenacibaculum/crescimento & desenvolvimento , Tenacibaculum/patogenicidade , Vibrio/genética , Vibrio/crescimento & desenvolvimento , Vibrio/patogenicidade
13.
Osteoporos Int ; 28(5): 1675-1683, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28204954

RESUMO

Results from bone biopsy and high-resolution peripheral quantitative computed tomography (HR-pQCT) were compared in 31 CKD patients. There was an agreement mainly for cortical compartment that may represent a perspective on the fracture risk assessment. HR-pQCT also provided some clues on the turnover status, which warrants further studies. INTRODUCTION: Chronic kidney disease (CKD) patients are at high risk of bone disease. Although bone biopsy is considered the best method to evaluate bone disease, it is expensive and not always available. Here we have compared, for the first time, data obtained from bone biopsy and HR-pQCT in a sample of CKD patients on dialysis. METHODS: HR-pQCT and dual-energy X-ray absorptiometry (DXA) were performed in 31 CKD patients (30 on dialysis). Biopsies were analyzed by quantitative histomorphometry, and classified according to TMV. RESULTS: We have found an inverse correlation between radius cortical density measured by HR-pQCT, with serum, as well as histomorphometric bone remodeling markers. Trabecular density and BV/TV measured through HR-pQCT in the distal radius correlated with trabecular and mineralized trabecular bone volume. Trabecular number, separation, and thickness obtained from HR-pQCT and from bone biopsy correlated with each other. Patients with cortical porosity on bone histomorphometry presented lower cortical density at the distal radius. Cortical density at radius was higher while bone alkaline phosphatase was lower in patients with low turnover. Combined, these parameters could identify the turnover status better than individually. CONCLUSIONS: There was an agreement between HR-pQCT and bone biopsy parameters, particularly in cortical compartment, which may point to a new perspective on the fracture risk assessment for CKD patients. Besides classical bone resorption markers, HR-pQCT provided some clues on the turnover status by measurements of cortical density at radius, although the significance of this finding warrants further studies.


Assuntos
Osteoporose/etiologia , Insuficiência Renal Crônica/complicações , Absorciometria de Fóton/métodos , Adulto , Biópsia , Densidade Óssea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/patologia , Osteoporose/fisiopatologia , Hormônio Paratireóideo/sangue , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/patologia , Rádio (Anatomia)/fisiopatologia , Diálise Renal , Insuficiência Renal Crônica/terapia , Reprodutibilidade dos Testes , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/fisiopatologia , Tomografia Computadorizada por Raios X/métodos
14.
Mar Pollut Bull ; 106(1-2): 183-9, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26980138

RESUMO

Microplastic pollution (particles <5mm) is a widespread marine threat and a trigger for biological effects, especially if ingested. The mussel Perna perna, an important food resource, was used as bioindicator to investigate the presence of microplastic pollution on Santos estuary, the most urbanized area of the coast of São Paulo State, Brazil. A simple and rapid assessment showed that 75% of sampled mussels had ingested microplastics, an issue of human and environmental concern. All sampling points had contaminated mussels and this contamination had no clear pattern of distribution along the estuary. This was the first time that microplastic bioavailability was assessed in nature for the southern hemisphere and that wild P. perna was found contaminated with this pollutant. This is an important issue that should be better assessed due to an increase in seafood consumption and culture in Brazil and worldwide.


Assuntos
Monitoramento Ambiental , Plásticos/análise , Poluentes Químicos da Água/análise , Animais , Brasil , Estuários , Perna (Organismo) , Alimentos Marinhos , Frutos do Mar , Urbanização
15.
Aquat Toxicol ; 157: 21-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25456216

RESUMO

Membrane pathway for intracellular cadmium (Cd(2+)) accumulation is not fully elucidated in many organisms and has not been studied in crab gill cells. To characterize membrane Cd(2+) transport of anterior and posterior gill cells of Ucides cordatus, a hypo-hyper-regulating crab, a change in intracellular Cd(2+) concentration under various experimental conditions was examined by using FluoZin, a fluorescent probe. The membrane Cd(2+) transport was estimated by the augmentation of FluoZin fluorescence induced by extracellular application of CdCl2 and different inhibitors. Addition of extracellular calcium (Ca(2+)) to the cells affected little the fluorescence of FluoZin, confirming that Cd(2+) was the main ion increasing intracellular fluorescence. Ca(2+) channels blockers (nimodipine and verapamil) decreased Cd(2+) influx as well as vanadate, a Ca(2+)-ATPase blocker. Chelating intracellular Ca(2+) (BAPTA) decreased Cd(2+) influx in gill cells, while increasing intracellular Ca(2+) (caffeine) augmented Cd influx. Cd(2+) and ATP added at different temporal conditions were not effective at increasing intracellular Cd(2+) accumulation. Ouabain (Na(+)/K(+)-ATPase inhibitor) increased Cd(2+) influx probably through a change in intracellular Na and/or a change in cell membrane potential. Routes of Cd(2+) influx, a non-essential metal, through the gill cell plasma membrane of crabs are suggested.


Assuntos
Braquiúros/metabolismo , Cádmio/metabolismo , Membrana Celular/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Braquiúros/efeitos dos fármacos , Cádmio/toxicidade , Cafeína/farmacologia , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Sobrevivência Celular , Quelantes/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Fluorescência , Corantes Fluorescentes/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Transporte de Íons/efeitos dos fármacos , Nimodipina/farmacologia , Vanadatos/farmacologia , Verapamil/farmacologia , Poluentes Químicos da Água/toxicidade
17.
Chaos ; 22(2): 026112, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22757571

RESUMO

The dynamics in weakly chaotic Hamiltonian systems strongly depends on initial conditions (ICs) and little can be affirmed about generic behaviors. Using two distinct Hamiltonian systems, namely one particle in an open rectangular billiard and four particles globally coupled on a discrete lattice, we show that in these models, the transition from integrable motion to weak chaos emerges via chaotic stripes as the nonlinear parameter is increased. The stripes represent intervals of initial conditions which generate chaotic trajectories and increase with the nonlinear parameter of the system. In the billiard case, the initial conditions are the injection angles. For higher-dimensional systems and small nonlinearities, the chaotic stripes are the initial condition inside which Arnold diffusion occurs.

18.
Minerva Endocrinol ; 37(3): 221-31, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22766889

RESUMO

Osteoporosis and high risk of fractures have emerged as frequent and devastating complications of organ solid transplantation process. Bone loss after organ transplant is related to adverse effects of immunosuppressive drugs on bone remodeling and bone quality. Many factors contribute to the pathogenesis of osteoporosis in transplanted patients. This review address the mechanisms of bone loss that occurs both in the early and late post-transplant periods including the contribution of the immunosuppressive agents as well as the specific features to bone loss after kidney, lung, liver and cardiac transplantation. Therapy for bone loss and prevention of fragility fracture in the transplant recipient will also be discussed.


Assuntos
Imunossupressores/efeitos adversos , Transplante de Órgãos , Osteoporose/induzido quimicamente , Densidade Óssea/efeitos dos fármacos , Medicina Baseada em Evidências , Transplante de Coração , Humanos , Imunossupressores/administração & dosagem , Transplante de Rim , Transplante de Fígado , Transplante de Pulmão , Osteoporose/prevenção & controle , Osteoporose/terapia , Fraturas por Osteoporose/etiologia
19.
Toxicol Mech Methods ; 21(8): 622-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21943233

RESUMO

A test chamber was projected and built (according to ISO 16000-9 Standard) to simulate atmospheric conditions experienced by rubber infill (when applied in synthetic turf pitches) and measure accurately the airborne emissions of pollutants such as dusts and volatile organic compounds (VOC), as well as pollutants present in leachates. It should be pointed out that standard ISO 16000-9 is only concerned with the determination of the emission of VOC from building products and furnishing (not specific of synthetic turf materials), whereas other standards are concerned with the emission of leachates only. This procedure is to be considered as a technical option to the lysimeter "global turf system evaluation" when the rubber infill alone is to be evaluated. The advantage of the proposed option considering this "test chamber" is its simplicity and economy. This test chamber is actually installed and being used for tests in LAIST.


Assuntos
Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Borracha/química , Borracha/toxicidade , Animais , Materiais de Construção , Monitoramento Ambiental , Teste de Materiais , Material Particulado/química , Reciclagem , Temperatura , Compostos Orgânicos Voláteis/química , Volatilização
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(5 Pt 2): 056201, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21728624

RESUMO

Rounding border effects at the escape point of open integrable billiards are analyzed via the escape-time statistics and emission angles. The model is the rectangular billiard and the shape of the escape point is assumed to have a semicircular form. Stickiness, chaos, and self-similar structures for the escape times and emission angles are generated inside "backgammon" like stripes of initial conditions. These stripes are born at the boundary between two different emission angles but with the same escape times and when rounding effects increase they start to overlap generating a very rich dynamics. Tiny rounded borders (around 0.1% from the whole billiard size) are shown to be sufficient to generate the sticky motion with power-law decay γ(esc)=1.27, while borders larger than 10% are enough to produce escape times related to the chaotic motion. Escape exponents in the interval 1<γ(esc)<2 are generated due to marginal unstable periodic orbits trapping alternately (in time) regular and chaotic trajectories.

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