78 research outputs found
Inorganic carbon assimilation by planktonic community in Santos Basin, Southwestern Atlantic Ocean
Primary production is essential in shaping biogeochemical cycles and microbial and ecosystem dynamics. Thedistribution of chemosynthetic rates in pelagic zones and their participation in the carbon cycle, especially whencompared to photosynthetic rates in the Southwestern Atlantic Ocean, are poorly constrained. This study aimedto measure pelagic photo- and chemosynthetic productivity and to analyze their spatial distribution and abioticdrivers. Samples for photosynthesis experiments collected at the surface and deep chlorophyll maximum (DCM)were incubated with 14C-bicarbonate at eight light levels, simulating in situ conditions. Samples for chemosynthesisexperiments were collected throughout the water column, from the surface, DCM, 250 m, 900 m, 1,200 m, and2,300 m, and were incubated in the dark. Rates were analyzed using statistical tests to verify spatial differencesbetween groups of samples and generalized linear models to identify correlations with environmental variables(temperature, salinity, density, mixed layer depth, dissolved oxygen, nitrite, nitrate, silicate, phosphate, turbidity,CDOM, and phycoerythrin and chlorophyll-a concentrations). Moreover, both processes were integrated from thesurface to the DCM and compared at the same stations to determine the relative contribution in the epipelagic zone.The photosynthetic and chemosynthetic rates were, on average, 3.00 ± 3.26 mg C m-3 h-1 and 0.97 ± 1.22 mg C m-3h-1, respectively. In most stations, chemosynthesis represented an average of 10.2% of total primary productivity,but surpassed photosynthesis in three experiments (reaching 63.4 – 78.8%). Photosynthesis displayed a clearoffshore-onshore gradient, along with correlated CDOM concentrations, indicating an autochthonous productionof the latter. Chemosynthesis, on the other hand, exhibited high variability and lack of prediction by studiedenvironmental variables, with isolated points of substantially higher activity
Instantaneous transport of salt, nutrients, suspended matter and chlorophyll-a in the tropical estuarine system of Santos
A contribuição dos canais estuarinos de Santos e São Vicente para a eutrofização da baía de Santos foi avaliada quantificando-se o transporte instantâneo de sal, fosfato e nitrogênio inorgânico dissolvido (NID), material em suspensão orgânico (MSO) e inorgânico (MSI) e clorofila-a, durante a estação seca (inverno austral- Agosto/1999) e chuvosa (verão austral- Janeiro/ 2000). As amostragens foram realizadas em períodos de sizígia e quadratura, durante as marés enchentes e vazantes, nas secções transversais das bocas dos canais de São Vicente e Santos. Os valores de transporte instantâneo obtidos durante o período de amostragem indicaram exportação de NID, principalmente sobre a forma de N-NH4 (valor máximo de 1155,1 g s-1) na estação chuvosa; importação de fosfato durante a estação seca (máximo de 385,6 g s-1) e exportação de MSI, MSO e clorofila-a em períodos de maior contribuição fluvial. Estes resultados indicam uma importante contribuição dos canais estuarinos de Santos e São Vicente para a eutrofização da baía de Santos, especialmente durante o período chuvoso.The contribution of the polluted São Vicente and Santos estuarine channels to the eutrophication of Santos bay was assessed through the quantification of instantaneous transport of salt, dissolved inorganic nitrogen (DIN) and phosphate, organic and inorganic matter (OSM and ISM) and chlorophyll-a (Chl-a), during dry (austral winter- August/ 1999) and rainy (austral summer- January/2000) seasons. Samplings were carried out during spring and neap tides, in flood and ebb phases, in two transversal sections at the mouths of the São Vicente and Santos channels. Instantaneous transport values generally indicated importation of salt to the estuarine channels, exportation of DIN to the bay, mainly as N-NH4, at a maximum rate of 1155.1 g s-1 during the rainy season; importation of phosphate during the dry season (maximum of 385 g s-1) and exportation of ISM, OSM and Chl-a during periods of greater freshwater discharge. These results demonstrate the great contribution made by the Santos and São Vicente estuaries to the eutrophication of Santos bay, especially in the rainy season
Exames de tomografia computadorizada e cintilografia para diagnóstico e plano de tratamento de osteocondroma condilar: relato de caso
PURPOSE: To report an uncommon case of osteochondroma affecting the mandibular condyle of a young patient and to illustrate the important contributions of different imaging resources to the diagnosis and treatment planning of this lesion. CASE DESCRIPTION: A 24-year-old female patient with the chief complaint of an increasing facial asymmetry and pain in the left pre-auricular region, revealing a reduced mouth opening, mandibular deviation and posterior cross-bite over a period of 18 months. Panoramic radiography revealed an enlargement of the left condyle, whereas computed tomography (CT) sections and three-dimensional CT showed a well-defined bone growth arising from condylar neck. The scintigraphy exam showed an abnormal osteogenic activity in the left temporomandibular joint. The condyle was surgically removed and after 18 months follow-up the panoramic radiography and CT scans showed no signs of recurrence. CONCLUSION: Although osteochondroma is a benign bone tumor that rarely arises in cranial and maxillofacial region, it should be considered in the differential diagnosis of slow-growing masses of the temporomandibular area and the use of different imaging exams significantly contribute to the correct diagnosis and treatment planning of this pathological condition.OBJETIVO: Relatar um caso incomum de osteocondroma afetando o côndilo mandibular de uma paciente jovem e ilustrar as importantes contribuições dos diferentes exames por imagem para o diagnóstico e plano de tratamento desta lesão. DESCRIÇÃO DO CASO: Paciente do sexo feminino, 24 anos, com queixa principal de uma crescente assimetria facial e dor na região pré-auricular esquerda, além de apresentar redução da abertura bucal, desvio de mandíbula e mordida cruzada posterior, por um período de 18 meses. A radiografia panorâmica revelou um aumento do côndilo esquerdo, enquanto secções de tomografia computadorizada e reconstrução 3D exibiram um crescimento ósseo bem definido originando-se do côndilo. O exame de cintilografia revelou uma atividade osteogênica anormal na região de articulação tempormandibular esquerda. O côndilo foi cirurgicamente removido e após 18 meses de acompanhamento a radiografia panorâmica e a tomografia computadorizada não revelaram nenhum sinal de recorrência. CONCLUSÃO: Apesar de o osteocondroma ser um tumor ósseo benigno que raramente surge na região crânio maxilofacial, ele deve ser considerado como diagnóstico diferencial para massas de crescimento lento na área temporomandibular e o uso de diferentes exames por imagem contribuem significativamente para o correto diagnóstico e plano de tratamento desta condição patológica
Human Papillomavirus Genotype Distribution among Cervical Cancer Patients prior to Brazilian National HPV Immunization Program
To evaluate the impact of HPV immunization and possible changes in virus type-specific prevalence associated with cervical cancer, it is important to obtain baseline information based on socioeconomic, educational, and environmental characteristics in human populations. We describe these characteristics and the type-specific HPV distribution in 1,183 women diagnosed with cervical cancer in two Brazilian healthcare institutions located at the Southeastern (Rio de Janeiro/RJ) and the Amazonian (Belém/PA) regions. Large differences were observed between women in these regions regarding economic, educational, and reproductive characteristics. The eight most frequent HPV types found in tumor samples were the following: 16, 18, 31, 33, 35, 45, 52, and 58. Some HPV types classified as unknown or low risk were found in tumor samples with single infections, HPV 83 in RJ and HPV 11, 61, and 69 in PA. The proportion of squamous cervical cancer was lower in RJ than in PA (76.3% versus 87.3%, 푝 < 0.001). Adenocarcinoma was more frequent in RJ than in PA (13.5% versus 6.9%, 푝 < 0.001). The frequency of HPV 16 in PA was higher in younger women (푝 < 0.05). The success of a cervical cancer control program should consider HPV types, local health system organization, and sociodemographic diversity of Brazilian regions
Human Papillomavirus Genotype Distribution among Cervical Cancer Patients prior to Brazilian National HPV Immunization Program
To evaluate the impact of HPV immunization and possible changes in virus type-specific prevalence associated with cervical cancer, it is important to obtain baseline information based on socioeconomic, educational, and environmental characteristics in human populations. We describe these characteristics and the type-specific HPV distribution in 1,183 women diagnosed with cervical cancer in two Brazilian healthcare institutions located at the Southeastern (Rio de Janeiro/RJ) and the Amazonian (Belém/PA) regions. Large differences were observed between women in these regions regarding economic, educational, and reproductive characteristics. The eight most frequent HPV types found in tumor samples were the following: 16, 18, 31, 33, 35, 45, 52, and 58. Some HPV types classified as unknown or low risk were found in tumor samples with single infections, HPV 83 in RJ and HPV 11, 61, and 69 in PA. The proportion of squamous cervical cancer was lower in RJ than in PA (76.3% versus 87.3%, p<0.001). Adenocarcinoma was more frequent in RJ than in PA (13.5% versus 6.9%, p<0.001). The frequency of HPV 16 in PA was higher in younger women (p<0.05). The success of a cervical cancer control program should consider HPV types, local health system organization, and sociodemographic diversity of Brazilian regions
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