Sunlight and vitamin D status in normal Saudi subjects

Serum levels of the circulating form of vitamin D3, 25-hydroxycholecalciferol [25-(OH)D3], were determined in 59 university students, 26 males and 33 females, aged 18 to 26 yr and in 24 elderly subjects, 13 males and 11 females, with a mean age of 62 +/- 13 yr. The level of 25-(OH)D3 was significantly lower in the elderly persons (p less than 0.001) than in young students of both sexes, and was significantly higher in females than in males. Serum levels of 1, 25- and 24, 25-dihydroxycholecalciferol were measured in adult males and found to be within the normal range. A group of elderly patients were exposed to natural uv light, and the circulating levels of 25-(OH)D3, serum phosphorus, and alkaline phosphatase were determined both before and 1 day after the last exposure. The exposure to natural uv light resulted in a 2 1/2-fold increase in the level of 25-(OH)D3 and a significant decrease in the activity of alkaline phosphatase, but no significant change in serum phosphorus concentrations was observed. It is concluded that the low vitamin D3 status in Saudis is mainly due to avoidance of sunlight exposure and other factors discussed below.     

Disposition of 9-beta-D-arabinofuranosyl-2-fluoroadenine in mice, dogs, and monkeys

The metabolic disposition of 9-beta-D-arabinofuranosyl-2-fluoroadenine (2-F-AraA) has been studied in mice, dogs, and monkeys after iv administration. Following injection of 2-F-AraA (30 mg/m2) into mice, serum levels fell with apparent half-lives of 17 min for the alpha-phase and 72 min for the beta-phase. For dogs given the same dose, these values were less than 5 and 112 min, and, for monkeys, 26 and 125 min, respectively. A higher concentration of metabolites was present in the serum of dogs than in the serum of mice and monkeys. Phosphorylated derivatives of 2-F-AraA were present in each of several mouse tissues examined; liver contained the highest concentration. In 24 hr, mice excreted more than half of the administered compound in the urine as unchanged 2-F-AraA. For dogs given a dose of 400 mg/m2, a single phase of disappearance of the drug (t1/2 = 130 min) was observed. For a single monkey, there were two phases, with half-lives of 15 min and 6.7 hr. In the urine, monkeys excreted about half of either dose as parent compound; but dogs excreted only about one-fourth as unchanged drug. These data indicate that 2-F-AraA is extensively metabolized by dogs but less so by mice and monkeys.     

Computed tomography of orbital medial wall fractures

Increasing experience with computed tomographic evaluation of head trauma reveals this radiologic modality to be superior to conventional polytomography in the assessment of certain areas of maxillofacial injury. A comparison of hypocycloidal polytomography and computed tomography in nine patients with fractures of the medial wall of the orbit reveals CT to be superior in localization of the fracture site, delineation of displaced bone fragments, and recognition of herniation of intraorbital contents into the ethmoid labyrinth. Information regarding damage to the nasolacrimal duct and associated intraorbital abnormalities such as the presence and location of hemorrhage and foreign bodies is also available from the CT scan.     

The effects of oral diazepam premedication on blood gases

Blood gas analysis was performed before and 1 h after 10 mg oral diazepam premedication on 50 adult male patients undergoing different surgical operations. There was a significant (p less than 0.01) decrease in arterial oxygen tension, a significant (p less than 0.01) increase in alveolar--arterial oxygen tension difference, and no significant change in arterial carbon dioxide tension or pH after administration of the drug. It is concluded that diazepam given by mouth 1 h before operation increases venous admixture. It is suggested therefore that oral diazepam premedication should be given cautiously to patients with impaired cardiorespiratory reserve, preferably without adding a narcotic drug.     

Clinical trial with 2% sodium cromoglycate (Opticrom) in vernal keratoconjunctivitis.

An open assessment study was carried out during the summer of 1972 in which 2% sodium cromoglycate eyedrops were evaluated in the treatment of patients with vernal keratoconjunctivitis. A highly significant number of patients found the eyedrops effective, while a marked improvement was recorded in mild and moderate cases; in severe cases or in acute exacerbations additional steroid therapy was recommended. Sodium cromoglycate eyedrops were found to be as effective as Decadron and superior to Antistin-Privine. Furthermore SCG eyedrops could replace or reduce local steroid therapy in vernal keratoconjuntivitis and so avert the possible rise in ocular tension caused by steroids.