Simultaneous analysis of hydrocortisone and hydrocortisone phosphate by high-pressure liquid chromatography: reversed-phase, ion-pairing approach

The reversed-phase, ion-pairing approach to high-pressure liquid chromatography was applied to the simultaneous analysis of hydrocortisone and its phosphate ester in laboratory-prepared samples and injectable solutions. Results of this technique were evaluated and compared with results of the official procedure.     

Microprocessor-based IEEE-488 interfacing unit as a development aid

The IEEE-488 standard has become one of the major standards for instrument interfacing used today, finding wide application in automatic test equipment and microcomputer-based controllers. This article describes a microprocessor-based IEEE-488 interfacing unit that is now in use as a development aid in our digital control laboratories. The unit offers an answer to specialized signal generation and intelligent data acquisition.     

Insulin reduces norepinephrine transporter mRNA in vivo in rat locus coeruleus

Acute and chronic in vitro insulin treatment can inhibit the uptake of norepinephrine (NE) by adult rat brain synaptosomes and slices, fetal neuronal cultures, and PC12 cells. In the present study we tested whether chronic in vivo insulin treatment could alter the biosynthetic capacity of rat locus coeruleus neurons for the NE transporter protein (NET). Chronic third ventricular insulin treatment resulted in a suppression of NET mRNA to about one third of the level of vehicle-treated controls. Our finding suggests that insulin may play a regulatory role in the synthesis of this transporter, thereby modulating activity in CNS noradrenergic pathways.     

The dos and don'ts of an oral mucosal biopsy performed by the general dentist

The recognition of a pathologic entity is only the first step in the chain of events which must be performed for accurate diagnoses and appropriate patient management. Other steps include selection of the type of biopsy to be performed; proper biopsy technique, instrumentation and specimen handling; appropriate fixation; detailed documentation; and postoperative patient instructions. If the clinician performs each step carefully and correctly, the patient is ensured of receiving an accurate diagnosis in the shortest possible period of time.     

Antibody selection for immunohistochemical survey of equine tissue

A membrane-bound protease induced by sulfur mustard in cultured normal human epidermal keratinocytes (NHEK) was purified and partially characterized. Maximum enzyme stimulation occurred at 16 hr after normal human epidermal keratinocytes were exposed to 300 microM sulfur mustard. Purification to homogeneity of the protease was accomplished by Triton X-100 solubilization, ultracentrifugation, and dialysis, followed by ion-exchange chromatography through DEAE-cellulose and finally hydrophobic column chromatography through phenyl Sepharose. Analysis of the purified enzyme by SDS-PAGE revealed a single polypeptide at the 80 kDa region. Further investigation of biochemical properties showed that a synthetic serine-specific Chromozym TRY peptide and the physiological protein laminin were good substrates for this enzyme. Moreover, this enzyme was inhibited mostly by the serine-protease inhibitors leupeptin and di-isopropyl fluorophosphate and not by the cysteine protease inhibitor E-64 or the metalloprotease inhibitor 1,10-phenanthroline (Component H, CH), indicating the serine protease nature of this enzyme. This enzyme had a pH optimum in the range of 7.0 to 8.0. Amino acid sequencing of the purified enzyme revealed that this enzyme belongs to the endopeptidase family (serine protease), and is homologous with a mammalian-type bacterial serine endopeptidase that can preferentially cleave K-X, including K-P. These results suggest that serine-protease stimulation may be one of the mechanisms of mustard-induced skin blister formation, and that some specific serine-protease inhibitors may be useful for the treatment of this sulfur mustard toxicity.     

Role of bronchial artery embolization in the management of hemoptysis

OBJECTIVE: To assess the modern morbidity of hemoptysis and the contribution of therapeutic bronchial artery embolization to its management. METHODS: Medical record review of patients admitted for the treatment of hemoptysis from January 1991 to November 1995 and of patients who had therapeutic bronchial artery embolization from June 1986 to August 1995. Hemoptysis was labeled major or minor. RESULTS: A total of 138 patients were admitted with hemoptysis, 31 with major and 107 with minor hemoptysis. No emergency pulmonary resections were required. Mean follow-up was 13.5 months. Mortality was 29.7% (41/138) but was caused by bronchial bleeding in only 4.3% (6/138). Twenty-six patients underwent therapeutic bronchial artery embolization (mean follow-up [range], 14 months [0.3-69.0 months]). The initial success rate (no further bleeding during the initial admission) was 85% (22/26). The long-term success rate (no further bleeding during follow-up) was 58% (15/26). Only 2 patients with therapeutic bronchial artery embolization died of further hemoptysis. CONCLUSIONS: Hemoptysis signals life-threatening diseases. Therapeutic bronchial artery embolization is a good treatment adjunct to control bronchial bleeding and reduces the need for high-risk emergency lung resections.