Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on l...Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on large yellow croaker (Pseudosciaena crocea). The fish were exposed to three concentrations of dissolved oxygen (DO; 1.5 mg/L and 2.0 mg/L, and 6.5 mg/L control). We collected blood after 6, 12, 24, 48, and 96 h exposure. There was a significant increase in red blood count, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin in the group exposed to 1.5 mg/L DO after 6 h or 12 h, and a delayed increase (only elevated after 48 h and 96 h) in these indices in the group exposed to 2.0 mg/L DO. Plasma glucose concentrations increased significantly in both hypoxic groups after 24 h. Furthermore, plasma lactate and lactate dehydrogenase activity increased significantly after the first 6 h exposure in both hypoxic groups. Our results suggest that large yellow croakers could not maintain the aerobic pathway and instead use anaerobic metabolism for survival when DO levels fall below 2.0 mg/L. We conclude that the occurrence of hypoxia (<2 mg/L DO) in the East China Sea could cause metabolic stress for large yellow croakers and may be partially responsible for the population decline of this species.展开更多
Therapeutic efficacy of QS （quinapyramine sulphate） and FCA （Freund＇s complete adjuvant） combination was studied. The aim of the study was to evaluate therapeutic efficacy of QS using FCA in Trypanosorna congolen...Therapeutic efficacy of QS （quinapyramine sulphate） and FCA （Freund＇s complete adjuvant） combination was studied. The aim of the study was to evaluate therapeutic efficacy of QS using FCA in Trypanosorna congolense infection. GrouPs treated with QS and FCA had parasite disappeared in peripheral circulation 2 days pi, relapse was observed one week later. Effect of treatment on rectal temperature shows no significance （p 〈 0.05）, normalization of rectal temperature occurred in QS and FCA treated groups （34.1℃） than untreated （42.8 ℃）, QS （37.4 ℃） and FCA （35.92 ℃） treated groups. Mean body weight was significant （p 〈 0.001） in QS and FCA, QS, and FCA groups. Packed cell volume and hemoglobin concentration for untreated groups were lower, but increased in QS, FCA, QS and FCA treated groups, indicating anemia amelioration. White blood cell counted in untreated, QS and FCA treated groups showed no significance （p 〈 0.05）, however, there was leukocytosis due to lymphocytosis in QS and FCA treated group （6.79 × 10^3/μl） compared with untreated and other groups. There was comparative decrease in serum liver enzymes in QS and FCA treated group than other groups. Therefore, QS at lower recommended dose with FCA may enhance efficacy of QS in trypanosomiasis.展开更多
基金Supported by the Special Research Fund for the National Non-profit Institutes (No. 2007M24)the Shanghai Postdoctoral Scientific Program (No. 07R214165)+1 种基金the National Natural Science Foundation of China (No. 40776047)the National Basic Research Program of China (973 Program) (No. 2010CB429005)
文摘Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on large yellow croaker (Pseudosciaena crocea). The fish were exposed to three concentrations of dissolved oxygen (DO; 1.5 mg/L and 2.0 mg/L, and 6.5 mg/L control). We collected blood after 6, 12, 24, 48, and 96 h exposure. There was a significant increase in red blood count, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin in the group exposed to 1.5 mg/L DO after 6 h or 12 h, and a delayed increase (only elevated after 48 h and 96 h) in these indices in the group exposed to 2.0 mg/L DO. Plasma glucose concentrations increased significantly in both hypoxic groups after 24 h. Furthermore, plasma lactate and lactate dehydrogenase activity increased significantly after the first 6 h exposure in both hypoxic groups. Our results suggest that large yellow croakers could not maintain the aerobic pathway and instead use anaerobic metabolism for survival when DO levels fall below 2.0 mg/L. We conclude that the occurrence of hypoxia (<2 mg/L DO) in the East China Sea could cause metabolic stress for large yellow croakers and may be partially responsible for the population decline of this species.
文摘Therapeutic efficacy of QS （quinapyramine sulphate） and FCA （Freund＇s complete adjuvant） combination was studied. The aim of the study was to evaluate therapeutic efficacy of QS using FCA in Trypanosorna congolense infection. GrouPs treated with QS and FCA had parasite disappeared in peripheral circulation 2 days pi, relapse was observed one week later. Effect of treatment on rectal temperature shows no significance （p 〈 0.05）, normalization of rectal temperature occurred in QS and FCA treated groups （34.1℃） than untreated （42.8 ℃）, QS （37.4 ℃） and FCA （35.92 ℃） treated groups. Mean body weight was significant （p 〈 0.001） in QS and FCA, QS, and FCA groups. Packed cell volume and hemoglobin concentration for untreated groups were lower, but increased in QS, FCA, QS and FCA treated groups, indicating anemia amelioration. White blood cell counted in untreated, QS and FCA treated groups showed no significance （p 〈 0.05）, however, there was leukocytosis due to lymphocytosis in QS and FCA treated group （6.79 × 10^3/μl） compared with untreated and other groups. There was comparative decrease in serum liver enzymes in QS and FCA treated group than other groups. Therefore, QS at lower recommended dose with FCA may enhance efficacy of QS in trypanosomiasis.
