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C B Michelsen

Publications and source records attributed to C B Michelsen.

23 records · Page 2Linked to original sources

Muscle and plasma amino acids after injury: the role of inactivity.

The amino acid pattern following total hip replacement is characterized by increases in muscle of the branched chain amino acids (leucine, isoleucine and valine), the aromatics (phenylalanine and tyrosine) as well as methionine. The nonessential amino acids in muscle tend to decline, glutamine having the most marked change. Plasma levels of the essential amino acids increase while the nonessentials tend to decrease. This pattern differs from that observed in other catabolic states (uremia, starvation, untreated diabetes) and is significantly different from the effects of inactivity and starvation combined. This suggests that injury can be characterized by a unique pattern of muscle and plasma amino acids.

Amino Acids↗

The significance of intracapsular cultures in total hip operations.

In a consecutive retrospective study of 1,500 total hip replacements, analysis of cultures taken at the time of operation revealed that positive cultures obtained in primary arthroplasties are not significant. In our series, no statistical difference could be demonstrated between primary and revision arthroplasty cultures as related to joint infection, but on the basis of other clinical studies and the higher incidence of positive cultures in revision arthroplasty cultures as related to joint infection, but on the basis of other clinical studies and the higher incidence of positive cultures in revision arthroplasties, it is believed that these cultures should be treated vigorously. Further studies are being carried out to help clarify the role of prophylactic antibiotics in hip replacement operations in the prevention of postoperative hip joint infection. Antibiotic therapy for the treatment of potentially contaminated hips is also being reviewed. Such studies must be performed over a long term period.

Arthroplasty↗

Preparative procedure for the purification of toxoids by gel filtration.

Sephadex gel filtration can be employed as a preparative procedure for the purification of both tetanus and diphtheria toxoids. A toxoid purification sequence is described in the text. By utilizing the described methods and columns, up to 100,000 human doses of diphtheria toxoid could be processed in a single operation. The method has given an 80% yield of diphtheria toxoid with a purity of 1,900 Lf per mg of N. The analysis of the material by immunodiffusion tests showed that a marked increase in purity was achieved. Antigenicity tests demonstrated that there was no significant difference in antigenic potency between the parent toxoid and its purified fraction. Factors limiting the effective separation of tetanus toxoid by gel filtration are discussed. The construction of the columns used is described in detail, as well as packing procedures and column characteristics such as bed volume, void volume, sample size, and flow rate.

Animals↗