Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea)

Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea). We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC). OC fluxes in the canyon and the open slope varied among sampling periods, though not onsistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April-May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea. Particles transferred to the deep sea floor through the canyons are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, oncurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of deep-sea ecosystems, and highlight the importance of canyons in linking episodic storms and primary production occurring at the sea surface to the deep sea floor.

Tumores malignos da cavidade nasal: tomografia computadorizada e ressonância magnética

OBJETIVO: Este estudo propõe-se a avaliar o papel da tomografia computadorizada e da ressonância magnética na caracterização da extensão profunda dos tumores malignos da cavidade nasal. MATERIAIS E MÉTODOS: Entre 1990 e 2000 foram avaliados, retrospectivamente, 12 pacientes com diagnóstico de tumores malignos da cavidade nasal atendidos nos Departamentos de Diagnóstico por Imagem e Cirurgia de Cabeça e Pescoço do Complexo Hospitalar Heliópolis, São Paulo, SP. Todos os casos foram confirmados com exame anatomopatológico. RESULTADOS: Foi identificada extensão para os seios maxilares e etmoidal em seis pacientes, para a cavidade nasal contralateral, órbita e lâmina crivosa em cinco pacientes, para a nasofaringe e espaço mastigatório em dois pacientes, e para o seio cavernoso, fossas cranianas anterior e média, fossa pterigomaxilar, fissuras orbitárias superior e inferior, seio frontal, seio etmoidal contralateral, lâmina crivosa contralateral, palato duro e fossa pterigopalatina em um paciente. CONCLUSÃO: A análise precisa da extensão local e disseminação tumoral dada pela tomografia computadorizada e ressonância magnética desempenha papel importante no planejamento terapêutico, influenciando também o prognóstico.

Proteasome inhibition reduces proliferation, collagen expression, and inflammatory cytokine production in nasal mucosa and polyp fibroblasts

Proteasome inhibitors, used in cancer treatment for their proapoptotic effects, have anti-inflammatory and antifibrotic effects on animal models of various inflammatory and fibrotic diseases. Their effects in cells from patients affected by either inflammatory or fibrotic diseases have been poorly investigated. Nasal polyposis is a chronic inflammatory disease of the sinus mucosa characterized by tissue inflammation and remodeling. We tested the hypothesis that proteasome inhibition of nasal polyp fibroblasts might reduce their proliferation and inflammatory and fibrotic response. Accordingly, we investigated the effect of the proteasome inhibitor Z-Leu-Leu-Leu-B(OH)2 (MG262) on cell viability and proliferation and on the production of collagen and inflammatory cytokines in nasal polyp and nasal mucosa fibroblasts obtained from surgery specimens. MG262 reduced the viability of nasal mucosa and polyp fibroblasts concentration- and time-dependently, with marked effects after 48 h of treatment. The proteasome inhibitor bortezomib provoked a similar effect. MG262-induced cell death involved loss of mitochondrial membrane potential, caspase-3 and poly(ADP-ribose) polymerase activation, induction of c-Jun phosphorylation, and mitogen-activated protein kinase phosphatase-1 expression. Low concentrations of MG262 provoked growth arrest, inhibited DNA replication and retinoblastoma phosphorylation, and increased expression of the cell cycle inhibitors p21 and p27. MG262 concentration-dependently inhibited basal and transforming growth factor-β-induced collagen mRNA expression and interleukin (IL)-1β-induced production of IL-6, IL-8, monocyte chemoattractant protein-1, regulated on activation normal T cell expressed and secreted, and granulocyte/macrophage colony-stimulating factor in both fibroblast types. MG262 inhibited IL-1β/tumor necrosis factor-α-induced activation of nuclear factor-κB. We conclude that noncytotoxic treatment with MG262 reduces the proliferative, fibrotic, and inflammatory response of nasal fibroblasts, whereas high MG262 concentrations induce apoptosis.

Proteasome inhibition reduces proliferation, collagen expression, and inflammatory cytokine production in nasal mucosa and polyp fibroblasts

Proteasome inhibitors, used in cancer treatment for their proapoptotic effects, have anti-inflammatory and antifibrotic effects on animal models of various inflammatory and fibrotic diseases. Their effects in cells from patients affected by either inflammatory or fibrotic diseases have been poorly investigated. Nasal polyposis is a chronic inflammatory disease of the sinus mucosa characterized by tissue inflammation and remodeling. We tested the hypothesis that proteasome inhibition of nasal polyp fibroblasts might reduce their proliferation and inflammatory and fibrotic response. Accordingly, we investigated the effect of the proteasome inhibitor Z-Leu-Leu-Leu-B(OH)2 (MG262) on cell viability and proliferation and on the production of collagen and inflammatory cytokines in nasal polyp and nasal mucosa fibroblasts obtained from surgery specimens. MG262 reduced the viability of nasal mucosa and polyp fibroblasts concentration- and time-dependently, with marked effects after 48 h of treatment. The proteasome inhibitor bortezomib provoked a similar effect. MG262-induced cell death involved loss of mitochondrial membrane potential, caspase-3 and poly(ADP-ribose) polymerase activation, induction of c-Jun phosphorylation, and mitogen-activated protein kinase phosphatase-1 expression. Low concentrations of MG262 provoked growth arrest, inhibited DNA replication and retinoblastoma phosphorylation, and increased expression of the cell cycle inhibitors p21 and p27. MG262 concentration-dependently inhibited basal and transforming growth factor-β-induced collagen mRNA expression and interleukin (IL)-1β-induced production of IL-6, IL-8, monocyte chemoattractant protein-1, regulated on activation normal T cell expressed and secreted, and granulocyte/macrophage colony-stimulating factor in both fibroblast types. MG262 inhibited IL-1β/tumor necrosis factor-α-induced activation of nuclear factor-κB. We conclude that noncytotoxic treatment with MG262 reduces the proliferative, fibrotic, and inflammatory response of nasal fibroblasts, whereas high MG262 concentrations induce apoptosis.

Tumores malignos da cavidade nasal: avaliação por tomografia computadorizada

OBJETIVO: Analisar os aspectos tomográficos dos tumores malignos da cavidade nasal. MATERIAIS E MÉTODOS: Foram estudados 18 pacientes - dez homens e oito mulheres - com tumor da cavidade nasal, os quais realizaram tomografia computadorizada da face. RESULTADOS: Dos tumores, seis eram casos de carcinoma epidermóide, três melanomas, dois carcinomas adenóides císticos, um adenocarcinoma polimórfico de baixo grau, um carcinoma indiferenciado, um carcinoma neuroendócrino, um linfoma não-Hodgkin, um rabdomiossarcoma alveolar, um sarcoma fusocelular grau II e um estesioneuroblastoma. As lesões foram mais freqüentes (p > 0,05) no lado esquerdo e no andar médio. CONCLUSÃO: Os carcinomas epidermóides apresentam grau de destruição correspondente ao seu volume, semelhante aos tumores epidermóides de outros sítios. O septo nasal foi acometido de maneira diferente, de acordo com os tipos histológicos.

Estudo da translucência nucal, ducto venoso, osso nasal e idade materna na detecção de cromossomopatia fetal em uma população de alto risco

OBJETIVO: Avaliar a translucência nucal, o ducto venoso, o osso nasal e a idade materna > 35 anos como testes de rastreamento para aneuploidias entre 12 e 14 semanas de gestação em pacientes de alto risco. MATERIAIS E MÉTODOS: Estudo prospectivo observacional envolvendo 92 gestantes entre 12 e 14 semanas submetidas a biópsia de vilo corial por alto risco de trissomia, baseado na medida da translucência nucal (17,4%) e idade materna >35 anos (78,3%). Antes da biópsia de vilo corial, realizaram-se medida da translucência nucal, avaliação de fluxo no ducto venoso e identificação do osso nasal. Calcularam-se a sensibilidade, a especificidade, o valor preditivo positivo e o valor preditivo negativo para testes realizados em paralelo e em seqüência. RESULTADOS: Encontrou-se alteração cromossômica em 12 (13,5%) fetos; 7 (58,3%) apresentavam trissomia 21. Osso nasal foi identificado em todos os fetos com trissomia. Translucência nucal, ducto venoso e idade materna isolados mostraram baixa sensibilidade (41,67-58,33%) e baixo valor preditivo positivo (10-45,45%). A associação translucência nucal + ducto venoso + idade materna apresentou o melhor resultado (sensibilidade: 100%; especificidade: 6,49%; valor preditivo positivo: 14,29%; valor preditivo negayivo: 100%). CONCLUSÃO: Em gestantes com idade > 35 anos, a associação translucência nucal + ducto venoso mostra-se como a mais sensível para a indicação de procedimento invasivo.

Análise por tomografia computadorizada do teto etmoidal: importante área de risco em cirurgia endoscópica nasal

OBJETIVO: Avaliar a profundidade das fossas olfatórias e a freqüência de assimetria na altura e na inclinação lateral do contorno do teto etmoidal. MATERIAIS E MÉTODOS: Estudo retrospectivo de 200 tomografias computadorizadas dos seios da face no plano coronal realizadas no período de agosto a dezembro de 2006. As profundidades das fossas olfatórias foram classificadas segundo Keros. O teto etmoidal foi avaliado quanto à simetria entre os lados. RESULTADOS: O tipo de Keros mais encontrado foi o tipo II (73,3%), seguido do tipo I (26,3%) e do tipo III (0,5%). Em 12% (24 exames) havia assimetria entre os lados quanto à altura do teto etmoidal, e em 48,5% (97 exames) observou-se assimetria do contorno do teto, com inclinação lateral da lâmina crivosa de um dos lados. CONCLUSÃO: Em relação à profundidade das fossas olfatórias, o tipo II de Keros foi o mais freqüente. Verificou-se que a assimetria do teto do seio etmoidal, na maioria dos casos, estava relacionada com a inclinação lateral da lamela lateral da lâmina crivosa.

Medida do comprimento do osso nasal entre 11 e 15 semanas de gestação em uma população brasileira: estudo preliminar

OBJETIVO: Determinar valores de referência para o comprimento do osso nasal entre 11 e 15 semanas de gestação em uma população brasileira. MATERIAIS E MÉTODOS: Realizou-se estudo de corte transversal com 171 gestantes normais entre 11 e 15 semanas completas. O osso nasal foi medido por via transabdominal em todos os casos. Foram calculados os percentis 5 a 95 para o comprimento do osso nasal pela fórmula: média ± 1,645 desvio-padrão. Para avaliar a correlação do comprimento do osso nasal com parâmetros antropométricos fetais utilizou-se o coeficiente de correlação de Spearman, com intervalo de confiança de 95%. RESULTADOS: O osso nasal foi mensurado em todos os casos, sendo que o comprimento médio variou de 1,69 mm a 2,94 mm. O comprimento do osso nasal mostrou-se fortemente correlacionado com todos os parâmetros antropométricos fetais (p < 0,001) e com a idade gestacional (R² = 0,59). CONCLUSÃO: Apesar de ser um estudo preliminar, a curva de referência do comprimento do osso nasal foi estabelecida.

Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films.

The biological uptake of plutonium (Pu) in aquatic ecosystems is of particular concern since it is an alpha-particle emitter with long half-life which can potentially contribute to the exposure of biota and humans. The diffusive gradients in thin films technique is introduced here for in-situ measurements of Pu bioavailability and speciation. A diffusion cell constructed for laboratory experiments with Pu and the newly developed protocol make it possible to simulate the environmental behavior of Pu in model solutions of various chemical compositions. Adjustment of the oxidation states to Pu(IV) and Pu(V) described in this protocol is essential in order to investigate the complex redox chemistry of plutonium in the environment. The calibration of this technique and the results obtained in the laboratory experiments enable to develop a specific DGT device for in-situ Pu measurements in freshwaters. Accelerator-based mass-spectrometry measurements of Pu accumulated by DGTs in a karst spring allowed determining the bioavailability of Pu in a mineral freshwater environment. Application of this protocol for Pu measurements using DGT devices has a large potential to improve our understanding of the speciation and the biological transfer of Pu in aquatic ecosystems.

Delivery of antigen to nasal-associated lymphoid tissue microfold cells through secretory IgA targeting local dendritic cells confers protective immunity.

BACKGROUND: Transmission of mucosal pathogens relies on their ability to bind to the surfaces of epithelial cells, to cross this thin barrier, and to gain access to target cells and tissues, leading to systemic infection. This implies that pathogen-specific immunity at mucosal sites is critical for the control of infectious agents using these routes to enter the body. Although mucosal delivery would ensure the best onset of protective immunity, most of the candidate vaccines are administered through the parenteral route. OBJECTIVE: The present study evaluates the feasibility of delivering the chemically bound p24gag (referred to as p24 in the text) HIV antigen through secretory IgA (SIgA) in nasal mucosae in mice. RESULTS: We show that SIgA interacts specifically with mucosal microfold cells present in the nasal-associated lymphoid tissue. p24-SIgA complexes are quickly taken up in the nasal cavity and selectively engulfed by mucosal dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin-positive dendritic cells. Nasal immunization with p24-SIgA elicits both a strong humoral and cellular immune response against p24 at the systemic and mucosal levels. This ensures effective protection against intranasal challenge with recombinant vaccinia virus encoding p24. CONCLUSION: This study represents the first example that underscores the remarkable potential of SIgA to serve as a carrier for a protein antigen in a mucosal vaccine approach targeting the nasal environment.

Concha nasal média secundária: relato de caso

A concha nasal média secundária é uma rara variação anatômica na cavidade nasal, descrita pela primeira vez por Khanobthamchai et al. como uma estrutura óssea revestida por partes moles originária da parede lateral do meato médio. Na maioria dos casos relatados na literatura ocorre bilateralmente, sem complicações associadas. Neste artigo descrevemos um caso encontrado em nosso serviço, com tal variação anatômica incomum.

The impact of bioavailability limitations on microbial stable isotope fractionation in a multiphase system

Stable isotope fractionation analysis of contaminants is a promising method for assessing biodegradation of contaminants in natural systems. However, standard procedures to determine stable isotope fractionation factors, so far, neglect the influence of pollutant bioavailability on stable isotope fractionation. On a microscale, bioavailability may vary due to the spatio-temporal variability of local contaminant concentrations, limited effective diffusivities of the contaminants and cell densities, and thus, the pollutant supply might not meet the intrinsic degradation capacity of the microorganisms. The aim of this study was to demonstrate the effect of bioavailability on the apparent stable isotope fractionation, using a multiphase laboratory setup. The data gained show that the apparent isotope fractionation factors observed during biodegradation processes depend on the amount of biomass and/or the rate of toluene mass transfer from a second to the aqueous phase. They indicate that physico-chemical processes need to be taken into account when stable isotope fractionation analysis is used for the quantification of environmental contaminant degradation.