Decreased total and ionized calcium levels and haematological indices in occupational lead exposure as evidence of the endocrine disruptive effect of lead

The multisystem and prime environmental and occupational toxin, lead (Pb) is seldom included in the list of endocrine disruptors group like bisphenols A, B and F, nonylphenol, benzoquine, equiline etc. One hundred and thirty-seven subjects consisting of 86 lead workers and 51 unexposed individuals (as controls) participated in the study. Dietary intake including dairy products and micronutrients as assessed by 24-hour dietary recall was similar between lead workers and controls. Calcium homeostasis and haematological indices were evaluated in all subjects. Blood lead level was significantly higher in the lead workers than in controls (P<0.001). Total and ionized calcium levels were in contrast significantly decreased in lead workers compared with controls (P<0.01, P<0.001 respectively). Inorganic phosphate level though slightly raised compared to controls did not reach statistical significance (P>0.05). The haematological indices, haemoglobin, haematocrit, and mean cell haemoglobin concentration like calcium levels were all significantly reduced (P<0.001) in all cases. Semi-quantitative assessment of erythrocyte protoporphyrin was trace (±) in both lead workers and controls (i.e. similar). Serum copper level was significantly higher in Pb workers than in controls (P<0.005). These decreases are consistent with a repression of the endocrine systems regulating both erythropoiesis and calcium homeostasis resident in the proximal convoluted tubule(PCT) of the kidney; the most vulnerable site to Pb damage. Our findings therefore, appear to provide evidence or a reminder that Pb satifies the conditions defining EDCs and should be recognized as one, especially in developing countries where high environmental Pb and malnutrition co-exist and may magnify this effec

Ascitic lipids and albumin gradient in the differentiation between cirrhotic and malignant ascites in Nigerian Africans

The purpose of this study was to investigate the efficacy of ascitic fluid lipid analysis, and to compare it with albumin gradient and AF total protein in discriminating between cirrhotic ascites and ascites caused by malignancies in Nigerian patients. 40 consecutive ascitic patients, (22 with cirrhotic ascites and 18 with neoplasms metastatic to the peritoneum) were studies prospectively. The roup with liver cirrhosis (LC) consisted of non-alcoholics; 60 percent were hepatitis B surface antigen positive. The patients with malignant ascites comprised four with ovarian carcinoma; three each of lymphoma, gastric and breast carcinoma; two bronchogenic carcinoma; and one each of prostatic, testicular and colon carcinoma. The results show that AF cholesterol provides excellent discrimination between the two types of ascites. Of five diagnostic parameters tested, AF cholesterol gave the best combination of results for the predictive value of a positive test and the predictive value of a negative test. Determination of AF cholesterol and albumin gradient are useful in differentiation ascites caused by malignancies from ascites due to LC. However, AF cholesterol measurement may have considerable advantages in cost effectiveness

Seasonal variations of the gravity wave momentum flux in the Antarctic mesosphere and lower thermosphere

Airglow imager and dynasonde/imaging Doppler interferometer (IDI) radar wind measurements at Halley Station, Antarctica (75.6degreesS, 26.6degreesW) have been used to estimate the seasonal variation of the vertical fluxes of horizontal momentum carried by high-frequency atmospheric gravity waves. The cross-correlation coefficients between the vertical and horizontal wind perturbations were calculated from sodium (Na) airglow imager data collected during the austral winter seasons of 2000 and 2001. These were combined with wind velocity variances from coincident radar measurements to estimate the daily averaged upper limit of the vertical flux of horizontal momentum due to gravity waves. The resulting momentum flux at the Na airglow altitudes, while displaying a large day-to-day variability, showed a marked rotation from the northwest to the southeast throughout the winter season. Calculations show that this rotation is consistent with seasonal changes in the wind field filtering of gravity waves below the Na airglow region. The calculations also indicate that while the magnitude of the meridional wind is small, this filtering leads to the observed seasonal changes in the meridional momentum flux