PubMed Health⌕ Search

Biomedical subjects

J A Koenig

Publications and source records attributed to J A Koenig.

22 records · Page 2Linked to original sources
PubMed1988

Works in progress #2. Threaded acetabular components. Design rationale and preliminary clinical experience.

Two design rationales for threaded acetabular components, the S-ROM Anderson cup and S-ROM SuperCup, are discussed. Components have been followed for at least six months, with a range of six to 24 months. The average follow up is nine months. One hundred components in 96 patients had sufficient follow up and full clinical and roentgenographic evaluations to be included in this study. The 100 hips were divided into four groups based on S-ROM Anderson cup versus S-ROM SuperCup and on primary versus revision. Each hip was evaluated on a clinical and radiologic basis. Based on clinical and roentgenographic evaluations of both the primary and revision situations of the S-ROM SuperCup, consistently good to excellent results were observed. To date, no case has undergone revision for clinical or roentgenographic failure. Dramatic pain relief was exhibited by 96% of patients. Although early results are very encouraging, longer follow ups are necessary.

Acetabulum↗
PubMedDate not supplied

Flavin-containing monooxygenase activity in human liver microsomes.

Human liver microsomal flavin-containing monooxygenase activity has been studied using dimethylaniline N-oxidation and thiobenzamide S-oxidation. Except for one subject, the capacity of human liver microsomes to mediate these reactions were markedly increased at pH 8.4 compared to pH 7.4. The mean dimethylaniline N-oxidase activities at pH 7.4 and 8.4 in the four subjects tested were 2.49 +/- 1.13 and 6.59 +/- 4.04 nmol mg-1 min-1, respectively (mean +/- SD, N = 4). The mean thiobenzamide S-oxidase activities at pH 7.4 and 8.4 were 1.39 +/- 0.51 and 2.74 +/- 1.28 nmol mg-1 min-1, respectively. At pH 7.4, an antibody to the human liver NADPH-cytochrome P-450 reductase inhibited dimethylaniline N-oxidation between 4 and 38%. The same antibody had no effect on this reaction at pH 8.4. Except for one subject, a battery of cytochrome P-450 inhibitors also had little effect on this reaction. Further, preincubating human microsomes at 45 degrees C in the absence of NADPH for 4 min destroyed approximately 90% of the dimethylaniline N-oxidase activity. These data collectively suggested that the flavin-containing mono-oxygenase is the major enzyme mediating this reaction in human liver microsomes. In contrast to dimethylaniline N-oxidation, thiobenzamide S-oxidation was significantly inhibited by the anti-reductase at both pH 7.4 and 8.4, respectively. These data indicate that cytochromes P-450 contribute significantly to this reaction in human liver microsomes.

Adolescent↗