ABSTRACT
Iron-containing preparations available on the market vary in dosage, salt, and chemical state of iron contained in the preparation, as well as in the iron delivery process (immediate or prolonged-release). The present study aimed at characterizing the serum pharmacokinetics of iron in non pregnant women with iron deficiency anaemia (IDA) following a single oral administration of a prolonged-release ferrous sulphate tablet. This multicenter, single dose, open-label study was conducted in 30 women aged between 18 and 45 years with IDA. A single 160 mg oral dose of ferrous sulphate was given as 2 tablets of 80 mg of Tardyferon(®) under fasting conditions. Blood samples were collected before dosing and until 24 h post-dosing. Serum iron concentrations were determined using a routine colorimetric analytical method. Pharmacokinetic parameters were determined from the serum concentration profiles using a non compartmental approach. Serum profiles showed elevated levels of iron up to 12 h after drug intake. The median time to maximum serum concentrations (Tmax) occurred 4 h post-dosing. Between 2 and 8 h post-dosing, mean serum iron concentrations fluctuated by only 20%. Additionally, C8h and C12h represented on average 78.6% and 47.5% of the Cmax, respectively. This study demonstrates that a single oral dose of 160 mg Tardyferon(®) administered under fasting condition to 30 women with IDA leads to an optimal long-lasting release of iron in the gastrointestinal tract in the targeted population. This allows the attainment and maintenance of elevated serum iron levels for up to 12 h after administration.
Subject(s)
Anemia, Iron-Deficiency/drug therapy , Ferrous Compounds/pharmacokinetics , Ferrous Compounds/therapeutic use , Mucins/pharmacokinetics , Mucins/therapeutic use , Administration, Oral , Adolescent , Adult , Anemia, Iron-Deficiency/metabolism , Delayed-Action Preparations/pharmacokinetics , Delayed-Action Preparations/therapeutic use , Drug Combinations , Female , Humans , Middle Aged , Tablets/pharmacokinetics , Tablets/therapeutic use , Young AdultABSTRACT
BACKGROUND: Hirschsprung's disease (HD) is widely quoted to have an incidence of approximately 1 in 5000 live births. However, it is also known that regional variation in incidence can occur. The aim of this paper was to study the incidence of Hirschsprung's disease in Tasmania and to document a regional experience of HD. METHODS: A retrospective review of all patients with newly diagnosed HD between January 1998 and December 2005 was carried out. Data were extracted from medical records and reported. Tasmanian birth statistics from 1998 to 2005 were obtained from the Australian Bureau of Statistics website and the incidence was calculated. RESULTS: Over the 8-year study period, 14 new cases of HD were identified in Tasmania. The estimated incidence of HD in Tasmania based on this study is 1 in 3429. This incidence is higher than the widely quoted incidence of 1 in 5000, but the difference did not reach statistical significance. Between 2003 and 2005, there was a surge in the number of cases with 11 of 14 cases being derived from these 3 years. No obvious reasons were found to explain this surge in the number of cases. Abdominal distension and vomiting were most common modes of presentation (100 and 71%, respectively). There was delayed passage of meconium in 43%. CONCLUSION: The incidence of Hirschsprung's disease seems higher in Tasmania. The surge in the number of cases is also of interest, although the reasons behind this remain unknown. Delayed passage of meconium was also less common than previously cited.
Subject(s)
Hirschsprung Disease/epidemiology , Population Surveillance , Adolescent , Child , Child, Preschool , Female , Hirschsprung Disease/diagnosis , Humans , Incidence , Infant , Infant, Newborn , Male , Retrospective Studies , Tasmania/epidemiologyABSTRACT
The time evolution of the isotopic composition of seawater strontium (the ratio of strontium-87 to strontium-86) over the last 500 million years has the form of an asymmetric trough. The values are highest in the Cambrian and Recent (0.7091) and lowest in the Jurassic (0.7067). Superimposed on this trend are a number of smaller oscillations. Consideration of the geochemical cycle of strontium and the dynamics of weathering shows that only Himalayan-style continental collisions can influence the isotope ratio on the scale observed. The contemporary Himalayan orogeny is by far the largest since the late Precambrian Pan-African event that produced the high in the Cambrian.
ABSTRACT
The submarine hydrothermal activity on and near the Galápagos Rift has been explored with the aid of the deep submersible Alvin. Analyses of water samples from hydrothermal vents reveal that hydrothermal activity provides significant or dominant sources and sinks for several components of seawater; studies of conductive and convective heat transfer suggest that two-thirds of the heat lost from new oceanic lithosphere at the Galápagos Rift in the first million years may be vented from thermal springs, predominantly along the axial ridge within the rift valley. The vent areas are populated by animal communities. They appear to utilize chemosynthesis by sulfur-oxidizing bacteria to derive their entire energy supply from reactions between the seawater and the rocks at high temperatures, rather than photosynthesis.
