Horner's syndrome in the emergency department.

We present a case of a 47-year-old female who was followed for 7 months with complaints of musculoskeletal pain involving the shoulder and scapula until she presented to the emergency department with Horner's syndrome and was diagnosed as having a superior pulmonary sulcus tumor. A review of the literature shows that although such tumors are a frequent cause of Horner's syndrome there are numerous other benign as well as malignant causes of Horner's syndrome. The differential diagnosis can be significantly narrowed by a knowledge of the anatomy and a careful physical examination. We present the anatomy, pathophysiology, differential diagnosis, and evaluation of patients who present to the emergency department with Horner's syndrome.

Saliva alcohol reagent strips in altered response protocols.

The prehospital care provider has been limited in his or her initial assessment of patients due to having available only a limited number of simple diagnostic tests. There has not been an accurate field test available to rule out significant ethanol intoxication. We designed a prospective trial for the prehospital setting to test the utility of a rapid, semi-quantitative, saliva alcohol reagent strip for patients with an altered level of consciousness. We found that these strips were useful in ruling out significant ethanol intoxication as a cause of an altered level of consciousness with a sensitivity of 85.7% and a specificity of 94.4%, but were not useful in accurately predicting the blood alcohol level. We conclude that these reagent strips are useful in the prehospital setting to provide information about patients with an altered level of consciousness.

Biogenesis of mitochondrial proteins. Regulation of production of delta-aminolaevulinate synthase by haemin in embryonic-chick liver.

The effect of haemin on the biogenesis of delta-aminolaevulinate synthase (ALA synthase) was investigated in primary cultures of embryonic-chick liver. The activity of the enzyme and the amount of the enzyme detected by 'immune-blotting' were determined in hepatocytes incubated with the porphyrogenic agent allylisopropylacetamide. The results of these studies indicated that the loss in ALA synthase activity in cells incubated in the presence of haemin (10 microM) was roughly proportional to a loss in the immune-reactive mass of the enzyme. Haemin was as effective as cycloheximide in causing depletion of ALA synthase in hepatocytes. We had previously established that haemin blocked the maturation of the precursor of ALA synthase [Ades (1983) Biochem. Biophys. Res. Commun. 110, 42-47]. From results reported in the present paper on analyses of immune-precipitated ALA synthase after pulse-labelling with [35S]methionine in the presence and in the absence of haemin, we determined that the inhibition of processing of pre-ALA synthase in cells by haemin was concentration-dependent. A concentration of 2 microM in the culture medium blocked the processing of pre-ALA synthase by 50% in hepatocytes. We also determined that, after inhibition of its maturation by haemin, pre-ALA synthase turned-over with a half-time of 30 min; on the other hand, mature ALA synthase turned-over with a half-time of 120 min.

Isolation of the mature subunit of delta-aminolaevulinate synthase from embryonic chick liver.

We presented evidence indicating that the established procedure for purifying delta-aminolaevulinate (ALA) synthase from embryonic-chick liver yielded an enzyme with a partially degraded subunit of molecular weight 51000 [Ades & Harpe (1981) J. Biol. Chem. 256, 9329-9333]. We now report the purification from livers of porphyric embryos of a preparation of ALA synthase which consisted primarily of a 63000-Da polypeptide and a component migrating as a smear of polypeptides with a minimum molecular weight of 52 000. Neither component could be recovered from liver mitochondria of normal embryos, where the amounts of ALA synthase were relatively low. The 52 000-Da component had been established to be the partially degraded subunit of the enzyme. Peptide-mapping analyses indicated that the 63 000- and the 52 000-Da components possessed significant structural homologies, and it was concluded that the 63 000-Da polypeptide represented the mature subunit of ALA synthase.

Biogenesis of mitochondrial proteins. Identification of the mature and precursor forms of the subunit of delta-aminolevulinate synthase from embryonic chick liver.

The purpose of this study was to determine the molecular weights of the mature subunit of embryonic chick liver delta-aminolevulinate synthase and of its putative precursor fom. Although an active enzyme with a subunit molecular weight of 51,000 could be purified from the livers of porphyric embryos, it was determined by immunoreplicate electrophoresis analyses of sodium dodecyl sulfate-solubilized liver homogenates and mitochondria from porphyric embryos that the actual molecular weight of the enzyme's subunit was 65,000 +/- 2,000. These results suggested that the usual procedure for purifying delta-aminolevulinate synthase from chick embryo yielded a partially degraded enzyme. When the products of cell-free translations of mRNA extracted from livers of porphyric embryos were analyzed, they contained a polypeptide of 75,000 +/- 400 daltons which specifically cross-reacted with anti-delta-aminolevulinate synthase. It is concluded that subunit of embryonic chick liver delta-aminolevulinate synthase present in mitochondria has a molecular weight of 65,000 and appears to be synthesized as a precursor of 75,000 daltons.