The Gidra population in lowland Papua New Guinea, having lived as a no-salt culture, is now subjected to modernization. In 1981, salt consumption, body fatness and blood pressures were measured for people in four ecologically different villages. Daily salt consumption of individuals was estimated from the sodium level per unit weight of creatinine in the morning urine and the daily urinary excretion of creatinine (estimation from fat free mass). The estimated value significantly correlated (r=0.53) with actually measured value in 30 selected subjects. Estimated sodium consumption and the urinary sodium potassium ratio were generally lower in remote villages from the town, and the salt consumption levels were less than 5 g/day/person in all the villages. Body fatness, calculated from the two skinfold values, was variable with sex, age group and village, the most being in the females in a coastal village which was adjacent to the town. The age-related increment of blood pressures was significant only in females; systolic blood pressure and pulse pressure were elevated in female elders. Conclusively, blood pressures were considered to be related, not to salt consumption, but to body fatness in the Gidra.

The cross-sectional association of blood pressure with urinary sodium and potassium excretion was investigated with a stepwise regression analysis. Spot urine of 7441 females between 40 and 69 years was collected from 169 municipalities (88 urban and 81 rural) covering all prefectures in Japan. The filter paper sampling technique for urine was used to collect samples of subjects from March to December in 1985. Spot urine samples were analyzed for sodium, potassium and creatinine. In addition, 24-hr sodium and potassium excretions were estimated by predictive equations. Blood pressure, sodium excretion and sodium/potassium ratios were higher in rural areas than in urban areas. Consistent positive correlations between urinary sodium and blood pressure, and negative correlations between urinary potassium and blood pressure were observed in the whole country of Japan, in both urban and rural areas, and also in separate observations of twelve regions in Japan with some exceptions. When compared in standardized partial regression coefficients, relative effects of potassium on systolic blood pressure were higher than those of sodium in the whole of Japan, in urban and rural areas, and in five among the twelve regions. The present Japanese study confirmed a positive within-population relationship between sodium excretion and blood pressure and a negative relationship between potassium excretion and blood pressure.

Lactic dehydrogenase (LDH) is a glycolytic enzyme that may be elevated in the serum of patients with gonadal and extragonadal germinomas. In this report, a case of unilateral ovarian pure dysgerminoma with remarkably elevated levels of serum LDH is presented. After complete excision of the tumor, serum LDH levels promptly returned to normal levels. Although an electrophoretic pattern of serum LDH isoenzymes was within normal limits pre-operatively, an increase in LDH-1 and 2 was found 1 week after operation. Seventeen additional examples of ovarian dysgerminomas with elevated serum LDH levels have been reported in the English literature including five cases who had high levels of two fast fractions of LDH. These data suggest that serum LDH levels and its isoenzymes pattern are useful tumor markers for diagnosis and post-therapy surveillance in patients with ovarian dysgerminomas.

No abstract