Environmental change in Jiaozhou Bay recorded by nutrient components in sediments

Inorganic or bulk organic chemical indicators, including organic carbon (OC), total nitrogen, organic nitrogen (ON), fixed ammonium (N-fix), exchangeable ammonium, exchangeable nitrate, organic phosphorus (OP), inorganic phosphorus (IP), and biogenic silica (BSi), were examined in a 3-m core collected in Jiaozhou Bay (JZB) to decipher how the environment has changed during the preceding two centuries of increasing anthropogenic influence in this region. Concentrations of BSi, OC, and OP reveal overall increases to ca.30 cm (similar to 1984), then decreased toward the surface, probably reflecting a decrease in the productivity of overlying waters since 1984. Aquaculture might play an important role in the decrease of nutrient elements in the upper layers recorded in sediments. The decreased molar BSi/OC ratios upcore may be due to a change in dominance from large- to small-sized diatoms, as shown in other research. However, the shift may also be related to changes from heavily-silicified to lightly-silicified diatoms or to non-siliceous forms such as dinoflagellates. ON concentrations increased towards the surface sediment, which is most likely consistent with the increase in fertilizer application and wastewater discharge. Concentrations of IP, total P. and Nfix all decreased conspicuously upcore at 41 cm depth (similar to 1977), and were largely consistent with the decrease in rainfall and freshwater discharge to JZB. Our data suggest that the environment has significantly changed since the 1980s. Anthropogenic activities in the watersheds may exert a substantial influence on carbon cycling processes in estuaries and potentially the coastal ocean. (C) 2010 Elsevier Ltd. All rights reserved

Periodic assessment of (ET-1) and Nitric Oxide (NO) in hypertensive disorders of pregnancy (HDP)

INTRODUCTION Hypertensive Disorders of Pregnancy (HDP) is an independent risk factor of cardiovascular (CVS) disease. Endothelin-1 (ET-1), a potent vasoconstrictor, has been identified as a pivotal mediator in both essential hypertension and HDP. Disturbances in Nitric Oxide (NO) bioavailability found in endothelial dysfunction may increase susceptibility to cardiovascular diseases. METHODOLOGY Thirty six pregnant women at 30-36 weeks period of gestation from the following categories (i) pregnancy induced hypertension (PIH) (ii) chronic hypertension during pregnancy (CH) and (iii) normal pregnant women (Control). Blood pressure indices measurements and sample collection was done at antepartum (30-36 weeks), post partum (8 weeks and 12 weeks). Endothelin-1 and serum NO were measured using the Human ET-1 (Endothelin-1) and NO ELISA Kit. RESULTS All blood pressure indices were significantly higher in HDP patients compared to control during antenatal and post partum periods. Serum ET-1 was significantly higher in patients with HDP compared to control during antenatal until 3 months post partum. This was accompanied by significantly lower levels of serum NO in HDP patients. CONCLUSION Persistently high levels of ET-1 and low levels of NO up to 3 months post partum in patients with history of HDP indicate presence of persistent endothelial dysfunction despite BP normalisation in PIH patients. Long term NO/ET-1 imbalance may account for the increased CVS disease risk