Flow-injection/pervaporation coupling for the determination of sulphide in Kraft liquors.

A dynamic manifold has been coupled with a pervaporation module for the determination of sulphide ion in complex matrices such as Kraft liquors. The method is based on ethylene blue formation and features detection limits of 0.68 and 0.42 microg mL(-1) of S(2-) for injection and continuous introduction of the sample, respectively, with linear ranges of 1-15 and 1-10 microg mL(-1). The method is highly selective as the interferences from other sulphur species are avoided in the pervaporation process; thus, it has been applied successfully to the determination of the analyte in white and green bleaching liquors.

Primary idiopathic hypomagnesemia in two female siblings.

Two female siblings with primary idiopathic hypomagnesemia, born to consanguineous parents, are described. Both presented at 6 weeks of age, with convulsions and persistent hypocalcemia (calcium 1.5 adn 1.6 mmol/l; normal range (NR) 2.2-2.6 mmol/l), which could not be controlled with anticonvulsants and/or calcium gluconate. On further investigation they were also found to have hypomagnesemia (magnesium 0.17 mmol/l and 0.22 mmol/l; NR 0.65-1.05 mmol/l). Convulsions and the low serum calcium and magnesium levels were first managed by im and then by oral administration of magnesium supplements. A burst in circulating parathyroid hormone levels to well above the physiological range was observed at the start of therapy. Serum magnesium values of the mother and father were just below the normal range, with normal serum calcium. This type of infantile primary hypomagnesemia appears to be a hereditary disease with autosomal recessive characteristics, although a partially penetrant X-linked or autosomal dominant trait cannot be excluded.

Bone minerals in beta-thalassemia minor.

Homozygous beta-thalassemia is a severe hereditary disorder associated with osteopenia. Recently it was suggested that thalassemia minor may be a risk factor for osteoporosis. The purpose of the present study was to investigate this suggestion. Bone mineral status was assessed in 22 premenopausal women and 21 men with beta-thalassemia minor. In vivo neutron activation analysis was applied to measure hand-bone phosphorus (HBP), single-photon absorptiometry to measure forearm bone mineral content (BMC), and dual-energy X-ray absorptiometry to measure spinal bone mineral density (BMD). Comparison of the HBP, BMC, and BMD values with those of sex- and age-matched healthy subjects without the beta-thalassemia trait failed to indicate a statistically significant difference for either sex group. Concerning the biochemical markers of bone metabolism that were studied (serum calcium, phosphate, alkaline phosphatase, osteocalcin, and parathyroid hormone, and 3-h fasting urine calcium-to-urine creatinine ratio) no difference was observed between the study subjects and matched controls. In conclusion, the present study showed that subjects with beta-thalassemia minor are not at risk for osteoporosis.