Assuntos

RESUMO

Longitudinal changes in composition, abundance, and distribution of copepods were studied at the transition zone of Paranapanema River-Jurumirim Reservoir (SP, Brazil). The interchange of biotic material between marginal lakes and the river system was also examined. Water samples were obtained from 6 stations along a stretch of 13 km of the Paranapanema River, from an upstream reach with high water velocity up to the river mouth into Jurumirim Reservoir. Two other sites in lateral lakes were also sampled. Nine copepod taxa were identified: 3 calanoids (Argyrodiaptomus furcatus Sars, Notodiaptomus iheringi Wright, and N. conifer Sars) and 6 cyclopoids (Eucyclops Claus, Microcyclops Claus, Mesocyclops longisetus Thiébaud, Thermocyclops decipiens Fischer, T. minutus Lowndes, and Paracyclops Claus). Harpacticoids were also collected. Calanoid and cyclopoid nauplii and copepodids, and harpacticoids were the most abundant organisms. In general, there was a longitudinal decrease in copepod abundance, whereas an increase was detected near the lakes. The abundance of most copepods was inversely correlated with current velocity and suspended solids. Higher abundance was observed in the river main course during the rainy season, during which there is a higher connectivity between the lakes and the main river. This promotes exportation of biologic material from marginal lakes to the river system, a biotic exchange reflecting the importance of marginal lakes to the river community structure.

Assuntos

RESUMO

O presente estudo foi realizado na zona de desembocadura do rio Paranapanema, na Represa de Jurumirim, visando a verificar as mudanças longitudinais na composição, abundância e distribuição dos Copepoda e a analisar a influência de lagoas laterais na exportação de material biótico para o rio. Foram amostrados 6 pontos no rio (trecho de 13 km), desde um local mais a montante, com alta velocidade da correnteza, até um local com características mais lênticas, na desembocadura do rio na represa, além de duas lagoas conectadas ao rio. Foram identificados 9 taxa: 3 Calanoida (Argyrodiaptomus furcatus Sars, Notodiaptomus iheringi Wright e N. conifer Sars) e 6 Cyclopoida (Eucyclops Claus, Microcyclops Claus, Mesocyclops longisetus Thiébaud, Thermocyclops decipiens Fischer, T. minutus Lowndes e Paracyclops Claus), além de representantes da ordem Harpacticoida. Os organismos mais abundantes foram as fases de desenvolvimento nauplius e copepoditos, de Calanoida e Cyclopoida e os Harpacticoida. De forma geral, observou-se diminuição na abundância dos Copepoda, do ponto 1 ao ponto 5, aumentando, porém, no ponto 6 e nas lagoas marginais. A maioria dos Copepoda mostrou relação inversa com a velocidade da corrente e o material em suspensão. Sazonalmente, as maiores abundâncias no canal do rio foram observadas no período chuvoso, refletindo a importância das lagoas laterais na estrutura da comunidade do rio, visto que nesse período ocorre maior conexão entre os ambientes, acarretando a exportação de material biológico das lagoas para o rio.

Assuntos

RESUMO

Longitudinal changes in composition, abundance, and distribution of copepods were studied at the transition zone of Paranapanema River-Jurumirim Reservoir (SP, Brazil). The interchange of biotic material between marginal lakes and the river system was also examined. Water samples were obtained from 6 stations along a stretch of 13 km of the Paranapanema River, from an upstream reach with high water velocity up to the river mouth into Jurumirim Reservoir. Two other sites in lateral lakes were also sampled. Nine copepod taxa were identified: 3 calanoids (Argyrodiaptomus furcatus Sars, Notodiaptomus iheringi Wright, and N. conifer Sars) and 6 cyclopoids (Eucyclops Claus, Microcyclops Claus, Mesocyclops longisetus Thiébaud, Thermocyclops decipiens Fischer, T. minutus Lowndes, and Paracyclops Claus). Harpacticoids were also collected. Calanoid and cyclopoid nauplii and copepodids, and harpacticoids were the most abundant organisms. In general, there was a longitudinal decrease in copepod abundance, whereas an increase was detected near the lakes. The abundance of most copepods was inversely correlated with current velocity and suspended solids. Higher abundance was observed in the river main course during the rainy season, during which there is a higher connectivity between the lakes and the main river. This promotes exportation of biologic material from marginal lakes to the river system, a biotic exchange reflecting the importance of marginal lakes to the river community structure.

O presente estudo foi realizado na zona de desembocadura do rio Paranapanema, na Represa de Jurumirim, visando a verificar as mudanças longitudinais na composição, abundância e distribuição dos Copepoda e a analisar a influência de lagoas laterais na exportação de material biótico para o rio. Foram amostrados 6 pontos no rio (trecho de 13 km), desde um local mais a montante, com alta velocidade da correnteza, até um local com características mais lênticas, na desembocadura do rio na represa, além de duas lagoas conectadas ao rio. Foram identificados 9 taxa: 3 Calanoida (Argyrodiaptomus furcatus Sars, Notodiaptomus iheringi Wright e N. conifer Sars) e 6 Cyclopoida (Eucyclops Claus, Microcyclops Claus, Mesocyclops longisetus Thiébaud, Thermocyclops decipiens Fischer, T. minutus Lowndes e Paracyclops Claus), além de representantes da ordem Harpacticoida. Os organismos mais abundantes foram as fases de desenvolvimento nauplius e copepoditos, de Calanoida e Cyclopoida e os Harpacticoida. De forma geral, observou-se diminuição na abundância dos Copepoda, do ponto 1 ao ponto 5, aumentando, porém, no ponto 6 e nas lagoas marginais. A maioria dos Copepoda mostrou relação inversa com a velocidade da corrente e o material em suspensão. Sazonalmente, as maiores abundâncias no canal do rio foram observadas no período chuvoso, refletindo a importância das lagoas laterais na estrutura da comunidade do rio, visto que nesse período ocorre maior conexão entre os ambientes, acarretando a exportação de material biológico das lagoas para o rio.

RESUMO

CD44 is a transmembrane glycoprotein involved in cell-cell and cell-substrate interactions. As a cell surface molecule, CD44 may be shed or released into the circulation by proteolytic enzymatic mechanisms. Therefore, soluble CD44 can be found in cell culture supernatants as well as in plasma. In this study we evaluated the levels of soluble total CD44 (sCD44) in serum samples of patients with breast and colorectal carcinoma as well as non-Hodgkin's lymphoma in order to correlate prognosis with sCD44 expression. Besides, we evaluated other clinical tumour markers routinely used, Cancer Antigen (CA) 15.3 and CA 19.9. We investigated 132 serological samples from breast cancer patients, 48 sera from colorectal tumours, 48 samples from stage IV non-Hodgkin's lymphoma and sera from 80 individuals without evidence of cancer or autoimmune disease. Breast cancer patients were divided into three groups: a) patients with no clinical evidence of positive nodules and no metastatic disease; b) patients with positive nodules; and c) patients with metastasis. sCD44 mean serum levels in these groups were 198+/-54 ng/ml, 221+/-78 ng/ml and 242+/-119 ng/ml, respectively, while the marker CA 15.3 values were 15.6+/-6.6 U/ml, 14.0+/-5.8 U/ml and 211.5+/-358.9 U/ml, respectively. sCD44 levels for colorectal tumour were 243+/-72 ng/ml, while CA 19.9 serum levels were 230+/-270 U/ml. Stage IV non-Hodgkin's lymphoma sCD44 levels were 398+/-160 ng/ml. sCD44, CA 15.3 and CA 19.9 values for healthy individuals without evidence of any cancer pathology were 223+/-58 ng/ml, 16.4+/-6.2 U/ml and 33+/-14 U/ml, respectively. From these results we conclude that sCD44 might be used as a reliable marker for patients with non-Hodgkin's lymphoma. However, sCD44 levels failed to correlate with prognosis, tumour burden or metastasis in breast and colorectal cancer patients. Neither was any correlation found between high CA 15.3 or CA 19.9 levels and soluble CD44 serum level.

Assuntos