A high-resolution method for amino acid analysis of physiological fluids containing mixed disulfides

In this paper we report a high-resolution method and special buffers for the analysis for 45 common amino acids and related compounds and seven less-common components occasionally found in physiological fluids. Careful optimization of the chromatographic protocol resolves cysteine-penicillamine mixed disulfide, penicillamine disulfide, and dihydroxyphenylalanine from cystine and methionine; cysteine-homocysteine mixed disulfide is eluted between tyrosine and phenylalanine. Argininosuccinic acid is eluted before ethanolamine; glycerophosphoethanolamine is separated from taurine; glucosaminic acid is eluted between urea and aspartic acid. A Beckman Instruments System 6300 Amino Acid Analyzer was used. System performance is examined in terms of coefficient of variation (CV) over the concentration range of 1.0-5.0 nmol/50 microL; average CV for all components is better than 1.5%. Method performance is assessed through the analysis of normal and abnormal urine and plasma specimens.     

EXTERNAL CEPHALIC VERSION

External cephalic version has been used periodically for centuries to manage breech presentations. As cesarean section rates have escalated in the last two decades, ways to curb this rise have been evaluated. By reducing the number of infants that arrive in labor in a representation, it is possible to impact the overall cesarean section rate. External cephalic version is a safe, effective method when used in appropriate cases of breech presentation. A forward or backward roll can be accomplished in women at term with singleton gestations, adequate amniotic fluid, and reactive nonstress tests. Parity, fetal and placental position, and descent of the presenting part may all influence the success rate of the version.     

Immunogold localization of type IV collagen and laminin in the aging human outflow system

Tissue from the outflow system of six surgically enucleated aged eyes was used for an ultrastructural immunocytochemical study of the distribution of laminin and type IV collagen. The immunogold technique provided precise localization of laminin beneath lining endothelial cells of the inner wall of Schlemm's canal. Laminin labelling was absent in the trabecular beams. Type IV collagen was found in the basement membranes of the trabecular beams and in fine filamentous basement membrane material in the cribriform layer. Electron dense plaques in the cribriform layer labelled positively for laminin in the outer coarse fibrillar zone but not in the electron dense core. Long-spacing collagen was negative for type IV collagen.     

Effects of alminoprofen on the allergic reactions

The effects of alminoprofen, a nonsteroidal anti-inflammatory agent, on the experimental animal models of allergic reactions were examined and compared with those of ibuprofen. Alminoprofen at 30 mg/kg given intraduodenally significantly suppressed passive anaphylactic bronchoconstrictions, while ibuprofen did not at the same doses. In vitro studies revealed that alminoprofen, in contrast to ibuprofen, exerted an inhibitory effect on arachidonate 5-lipoxygenase activity which initiates the bio-synthesis of leukotrienes. Alminoprofen inhibited arachidonic acid-induced ear edema in mice and homologous passive cutaneous anaphylaxis in rats at high doses, while ibuprofen did not at the high doses. From its characteristic feature of inhibitory effects on 5-lipoxygenase activity and the experimental model of type I allergic reaction, it is suggested that alminoprofen is a new type of nonsteroidal anti-inflammatory agent.     

A profile of tobacco use among teenage dependents.

This study profiles tobacco use by 2,241 dependent teenagers in grades 6-12 at two Army posts. Data were collected in February 1989 by self-administered questionnaires. Results show 40.9% of dependent teenagers have tried smoking and 16.4% have tried smokeless tobacco. Most youths who tried tobacco did so experimentally. Current use is 10.4% smoking and 2.8% smokeless tobacco. While there is little difference in the proportion of boys and girls who have tried or currently smoke, trial and current use of smokeless tobacco is almost exclusively by males. Whites are more likely to ever use tobacco than other ethnic groups.     

Effects of Nitrite Exposure on Acid–Base Balance, Respiratory Protein, and Ion Concentrations of Giant Freshwater Prawn Macrobrachium rosenbergii at Low pH

Macrobrachium rosenbergii that had been exposed individually for 24 h to 0 (control), 2, 5, 10 mg/L nitrite-N (nitrite as nitrogen) at 4.3 and 7.7 pH levels were examined for hemolymph nitrite-N, oxyhemocyanin, protein, acid–base balance, ion concentrations, and ammonia-N (ammonia as nitrogen) excretion. Hemolymph oxyhemocyanin, protein, pH, HCO₃ ⁻ , TCO₂, osmolality, and ion concentrations were inversely related to ambient nitrite-N concentration and were lower at pH 4.3. However, hemolymph nitrite-N, PO₂ and PCO₂ levels, and ammonia-N excretion were directly related to ambient nitrite-N, and were higher at pH 4.3. Ambient nitrite-N and pH level interacted to cause changes in hemolymph nitrite-N, oxyhemocyanin, protein, PO₂, and pH levels. It is concluded that for M. rosenbergii following nitrite exposure, the incorporated nitrite causes a decrease of pH and an increase of PO₂ in the hemolymph where it reduces oxyhemocyanin level; disturbs nitrogen excretion, ion regulation, and respiratory gas exchange; and may lead to a decrease of oxygen-carrying capacity, which are affected more at low pH. Received: 31 August 1996/Accepted: 9 July 1997     

Case report 733

Calcific tendinitis at the site of origin of the rectus femoris muscle is a rare lesion. Presumed to be formed by deposition of hydroxyapatite crystals, this entity may be confused with other lesions such as os acetabuli or posttraumatic abnormalities. The characteristic location and appearance of the calcifications in a symptomatic patient with no history of trauma should allow diagnosis and subsequent symptomatic therapy.