Distribution and sources of aliphatic and polycyclic aromatic hydrocarbons in surface sediments of Itajaí-Açu estuarine system in Brazil

The Itajaí-Açu estuarine system, located in southern Brazil, has great economic importance due to the presence of two ports (Itajaí and Navegantes). This system is affected by industrial and dredging activities, which can cause the remobilization of pollutants accumulated over time in the sediment. In this context, hydrocarbons were assessed in twelve surface sediment samples. n-Alkane and polycyclic aromatic hydrocarbons (PAH) concentrations were determined by gas chromatography and their sources assessed. Total concentrations ranged between 0.50 ± 0.04 and 69.70 ± 3.90 μg g-1 dry weight (d.w.) for n-alkanes and from 63.9 ± 12.1 to 1459.0 ± 43.5 ng g-1 d.w. for PAH. Most of the sediment samples presented carbon preference index (CPI) values close to unity, indicating that the area is submitted to petroleum-related sources, mainly close to Itajaí harbor, where an intense unresolved complex mixture (UCM) was observed. The presence at all stations of αβ-hopane biomarkers also indicated petrogenic input. Based on selected PAH ratios, the sedimentary PAH composition reflects a mixture of both petrogenic and pyrolytic sources. A comparison of the PAH concentrations found in this study with those listed in the sediment quality guidelines (SQGs) indicated that adverse biological effects on the biota are rarely expected.The Itajaí-Açu estuarine system, located in southern Brazil, has great economic importance due to the presence of two ports (Itajaí and Navegantes). This system is affected by industrial and dredging activities, which can cause the remobilization of pollu28460361

Mouse anti-RANKL antibody delays oral wound healing and increases TRAP-positive mononuclear cells in bone marrow

Objectives: Denosumab, a human monoclonal antibody (mAb) that neutralizes receptor activator for nuclear factor κB ligand (RANKL), is associated with osteonecrosis of the jaw. However, the effect of denosumab on oral wounds is unclear. The aim was to determine the effect of anti-RANKL mAb on oral wounds and bone marrow. Materials and methods: The direct effect of the mAb on fibroblasts, macrophages, and osteoclasts were assessed in vitro. In vivo, mouse anti-RANKL mAb was administered to mice for 9 weeks prior to palatal bone denudation surgery. Mice were euthanized 3 weeks post-surgery, and wound healing was histomorphometrically analyzed. Long bones were assessed using micro-computed tomography, quantitative real-time polymerase chain reaction, and flow cytometry. Results: The mAb had no effect on macrophages and fibroblasts but significantly suppressed osteoclast proliferation in vitro. The mAb treatment significantly increased bone mass by suppressing osteoclasts in vivo. The expression of pro-osteoclastic genes was promoted in the bone marrow of the mAb-administered animals. Consistently, the mAb significantly induced the development of tartrate-resistant acid phosphatase (TRAP)-positive mononuclear cells (MNCs) but not osteoclasts in bone marrow. The mAb treatment had no effect on gross healing of the palatal wounds. However, significant inflammation was retained in the connective tissue facing the once denuded bone surface. Conclusions: Repair of the damaged palate was delayed, and significant inflammation was sustained in the connective tissue by anti-RANKL mAb treatment. Clinical relevance: Denosumab impairs osteoclastic bone repair. Care should be exercised to minimize osseous trauma when invasive procedures are performed on patients taking denosumab

Electronic structure of Si and Ge gold-doped clathrates

The electronic properties of single phase type-I clathrate compounds, Ba8Au6(SiorGe)40 and Ba8Ge46-x have been investigated. The crystal structure, electrical resistivities, magnetic susceptibilities, the density of states at the Fermi level, and the band gap (where applicable) were determined. Ba8Au6Si40 and Ba8Au6Ge40 show a metallic behavior whereas Ba8Ge46-x is semiconducting. On a basis of this work, a first evidence is presented of the existence of type-I mixed-clathrates containing both silicon and germanium

Pegada de carbono em áreas de maricultura.

A emissão de dióxido de carbono (CO2) e metano (CH4) pelas atividades de maricultura (malacocultura e algicultura) mundial ainda é pouco estudada, em contraste com outras atividades de cultivo como bovinocultura e suinocultura. A pegada de Carbono consiste na estimativa da quantidade global de emissões de GEE associadas a um produto ao longo de sua cadeia de suprimentos limitada ao estudo apenas ao impacto ambiental com relação ao potencial global de aquecimento. A fim de determinar a pegada de carbono de diferentes áreas de maricultura foi realizada determinação do fluxo de CO2 e estimativa do sequestro de C na calcificação das conchas e conversão de biomassa em cultivos de moluscos das espécies Crassostrea gigas, Perna perna e da macroalga Kappaphycus alvarezii. Os valores de fluxo de CO2 e CH4 utilizados foram coletados com câmaras de difusão nas áreas de produção. As amostras foram coletadas e analisadas posteriormente por cromatografia gasosa. O cálculo para estimar a conversão de carbono é obtido pela soma das emissões (CO2 e CH4). A pegada de carbono associada às ostras é dada pelo somatório do balanço de GEE na área de produção (-2,2 g C/kg de mexilhão in natura) com o sequestro realizado pelas conchas (-66,4 g C/kg de mexilhão in natura). Já para mexilhões o balanço de GEE na área de produção foi de -2,3 g C/kg de ostra in natura e considerando apenas o sequestro realizado pela conversão de carbono as conchas de -94 g C/kg de ostra in natura. O somatório do balanço de carbono demonstrou que a ostreicultura teve o maior sequestro de carbono (-91,7 g C/kg de ostra in natura), seguido pela mitilicultura (-68,6 g C/kg de mexilhão in natura) e a algicultura (-60,4 g C/kg de alga seca). O cálculo realizado utilizou apenas os valores de carbono associados diretamente ao sequestro na área de cultivo e o sequestro realizado pelas conchas, não considerando os demais fatores emissores de gases de efeito estufa. Uma avaliação holística do balanço de CO2 deve ser realizada através de estudos de impacto do ciclo de vida. Do ponto de vista da produção, sem levar em conta os processos de processamento, estocagem e transporte, os cultivos de moluscos e macroalga apresentaram uma tendência ao sequestro de carbono, indo de encontro às atividades tradicionais de agricultura e pecuária

VARIABILIDADE NAS TAXAS FISIOLÓGICAS DO MEXILHÃO PERNA PERNA EM DOIS SÍTIOS DE CULTIVO DO LITORAL NORTE DE SANTA CATARINA

With the growing socioeconomic activity of mussel farming on Santa Catarina’s coast, the identification of new cultivation sites became necessary. Among a variety of methods used for the analysis of potential producing areas, studying of the mussel physiological rates may be considered as one of the most appropriated, specially when addressing the monitoring of sites already established and the negative effects of environmental pollution. This report presents a preliminary comparison between two areas of cultivation in the northern coast of the state (municipalities of Penha and Bombinhas). In both locations, environmental data (temperature, salinity and seston) and physiological parameters of the mussels (growth, and filtration, respiration and assimilation rates) were analysed. Our findings suggested a direct relationship between temperature and mussel growth rate and also between salinity and respiration rates for both areas. The seston concentration showed a high environmental variability as a response to the continental drainage. In addition, the filtration and assimilation rates seemed to be influenced by the stages of embryonic follicle maturation. In terms of production, the sites showed larger differences during the colder months as compared to the warmer ones, when the results were quite similar. More conclusive results are dependent of studies conducted along a complete annual cycle.Com a crescente atividade sócio-econômica da mitilicultura na costa do estado de Santa Catarina, problemas relacionados com a identificação de novos sítios de cultivo tornaram-se prioritários. Dentre os mais diferentes métodos utilizados para análise de potenciais regiões produtoras, o estudo das taxas fisiológicas dos mexilhões enquadram-se como uma das mais adequadas, incluindo neste caso, o monitoramento de sítios já estabelecidos e problemas relacionados com a poluição ambiental. Este relatório faz referência a uma preliminar comparação entre duas áreas de cultivo do mexilhão Perna perna no litoral norte do estado (municípios de Penha e Bombinhas). Dados ambientais de temperatura, salinidade, material em suspensão e fisiológicos do mexilhão como crescimento, filtração, respiração e assimilação foram comparados. Os principais resultados deste estudo podem ser resumidos em: relação direta entre a temperatura e a taxa de crescimento e relação entre a salinidade e a taxa de respiração para os dois ambientes. O material em suspensão apresentou uma maior variabilidade ambiental influenciada pelos aportes continentais mas que necessitam de maiores investigações. A importância das taxas de maturação dos folículos embrionários dos mexilhões foi sugerida na relação com as taxas de filtração e assimilação. Em termos de produção, os ambientes mostraram maiores diferenças nos meses frios e similar resultados nos meses quentes. Entretanto, resultados conclusivos estão dependentes de estudos ao longo de um ciclo anual

Balanço de gases de efeito estufa em áreas de malacocultura.

O papel da malacocultura no balanço de gases de efeito estufa (GEE) ainda é controverso. A produção de ostras e mexilhões é apontada por alguns estudos como uma fonte emissora de GEE através da respiração dos animais e acúmulo de pseudofezes no sedimento. Entretanto, outros estudos sugerem que a malacocultura pode atuar como um sumidouro de GEE através da imobilização de carbono nas conchas. O presente estudo avaliou o fluxo de CO2 e CH4 na interface água atmosfera em três áreas de malacocultura em Santa Catarina. Foram realizadas cinco campanhas extensivas de coleta de amostras e dados nos anos de 2018 e 2019 em áreas de produção e controles em Penha, Ribeirão da Ilha e Palhoça. As amostras de GEE foram coletadas com câmaras estáticas no período da manhã e novamente no período da tarde. As concentrações de GEE em cada amostra foram determinadas por cromatografia gasosa no laboratório da Embrapa Meio Ambiente (Jaguariúna-SP). A média de CO2 foi de 10,1 ± 43,0 mg C-CO2 m-2 d-1 nas áreas de produção e 18,2 ± 51,1 mg C-CO2 m-2 d-1 nas áreas de controle. A média de CH4 foi de 0,23 ± 0,27 mg C-CH4 m-2 d-1 nas áreas de produção e 0,32 ± 0,30 mg C-CH4 m-2 d-1 nas áreas de controle. Para ambos os gases, a emissão de carbono foi ligeiramente menor nas áreas de malacocultura quando comparadas com as áreas controle (sem produção), apesar de não ter sido verificada diferença estatística entre as áreas. Os resultados obtidos sugerem que a malacocultura não teve impacto na emissão de CO2 e CH4. Esta conclusão é referente apenas à emissão direta dos gases produzidos na coluna d?água e liberados para a atmosfera, sem considerar o carbono sequestrado no processo de formação das conchas

Early effects of parathyroid hormone on bisphosphonate/steroid-associated compromised osseous wound healing

Summary: Administration of intermittent parathyroid hormone (PTH) promoted healing of tibial osseous defects and tooth extraction wounds and prevented the development of necrotic lesions in rats on a combined bisphosphonate and steroid regimen. Introduction: Osteonecrosis of the jaw (ONJ) has emerged in association with antiresorptive therapies. The pathophysiology of ONJ is unknown and no established cure currently exists. Our objective was to determine the effect of intermittent PTH administration on early osseous healing in the jaw and long bones of rats receiving bisphosphonate and steroid treatment. Methods: Ovariectomized rats received the combination therapy of alendronate and dexamethasone (ALN/DEX) for 12 weeks. Osseous wounds were created in the jaw and tibia. PTH was administered intermittently and healing at 2 weeks post-op was compared between the jaw and tibia by microcomputed tomography and histomorphometric analyses. Results: ALN/DEX treatment was associated with necrotic open wounds in the jaw but had no negative effects on healing and promoted bone fill in tibial defects. PTH therapy prevented the development of necrotic lesions in the jaw and promoted healing of the tibial defects. PTH therapy was associated with the promotion of osteocyte survival in osseous wounds both in the jaw and tibia. Conclusions: Wound healing was impaired in the jaw in rats on a combined bisphosphonate and steroid regimen, and PTH therapy rescued necrotic lesions. These findings suggest that PTH therapy could be utilized to prevent ONJ from occurring in patients on combination antiresorptive and steroid therapy

HuR is exported to the cytoplasm in oral cancer cells in a different manner from that of normal cells

HuR, a ubiquitously expressed member of the Hu protein family that binds and stabilizes an AU-rich element (ARE)-containing mRNAs, is known to shuttle between the nucleus and the cytoplasm via several export pathways. When normal cells were treated with heat shock, HuR was exported to the cytoplasm in a chromosome maintenance region 1 (CRM1)-dependent manner. However, in this study, we demonstrate that HuR is exported to the cytoplasm in oral cancer cells even if the cells were treated with the inhibitor of the CRM1-independent export pathway. Immunohistochemical and biochemical analyses showed that HuR existed in both the cytoplasm and the nucleus in oral cancer cells, such as HSC-3 and Ca9.22, but existed entirely inside the nucleus in normal cells. AU-rich element-mRNAs were also exported to the cytoplasm and stabilised in the oral cancer cells, which were inhibited by HuR knockdown. This export of HuR was not affected by at least 7 h of treatment of leptomycin B (LMB), which is an inhibitor of the CRM1-dependent export pathway. These findings suggest that HuR is exported to the cytoplasm in oral carcinoma cells in a different manner from that of normal cells, and is likely to occur through the perturbation of a normal export pathway

HbA1c levels in schoolchildren with type 1 diabetes are seasonally variable and dependent on weather conditions

Aims/hypothesis: We evaluated seasonal HbA$_{1c}$ changes in children with type 1 diabetes and its relation with measures of weather conditions. Methods: HbA$_{1c}$ changes over more than 3 years were evaluated in type 1 diabetic patients who were younger than 18 years and had diabetes duration of more than 12 months, and correlated with measures of weather conditions (ambient temperature, hours of sunshine and solar irradiance). After comparison of autocorrelation patterns, patterns of metabolic control and meteorological data were evaluated using Spearman rank correlation. Results: A total of 3,935 HbA$_{1c}$ measurements in 589 school (≥7 years) and 88 preschool (<7 years) children were analysed. Mean (±SD) HbA$_{1c}$ level for the whole study period was 7.65±1.12%. The lowest HbA$_{1c}$ levels were observed in late summer and the highest in winter months, with differences consistently exceeding 0.44%. Autocorrelation analysis of HbA$_{1c}$ levels in schoolchildren showed a sine-wave pattern with a cycle length of roughly 12 months, which mirrored changes in ambient temperature. Strong negative correlations of HbA$_{1c}$ with ambient temperature (R=−0.56; p=0.0002), hours of sunshine (R=−0.52; p=0.0007) and solar irradiance (R=−0.52; p=0.0006) were present in schoolchildren, but not in preschoolers (p≥0.29 for each correlation). Conclusions/interpretation: Seasonal changes of HbA$_{1c}$ levels in schoolchildren with type 1 diabetes are a significant phenomenon and should be considered in patient education and diabetes management. They may potentially affect the results of clinical trials using HbA$_{1c}$ levels as their primary outcome, as well as HbA$_{1c}$-based diagnosis of diabetes