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Biomedical subjects

K M Fallon

Publications and source records attributed to K M Fallon.

4 recordsLinked to original sources

Polyamines in relation to growth in carrot cell cultures.

Changes in polyamine metabolism were investigated in relation to growth of cell suspension cultures of carrot (Daucus carota, cv Chantenay). Changes in levels of the major amines putrescine and spermidine throughout the culture period correlated poorly with changes in fresh weight, but a closer correlation with the minor component spermine was observed. The arginine decarboxylase (ADC) inhibitor difluoromethylarginine (DFMA) strongly and specifically inhibited ADC activity in the supernatant, reduced the major amine (putrescine) by 95% and the total amine content by 80%. It had no effect on cell number and stimulated fresh weight by over 25% through increased cell expansion. Spermine content, in contrast, increased with DFMA concentration in parallel with fresh weight increases. Difluoromethylornithine strongly inhibited ornithine decarboxylase activity in the pellet, but had little effect on either polyamine levels or culture growth. It was concluded that little evidence for a correlation between free polyamines and cell number in carrot cultures could be detected, but that a possible correlation between spermine content and cell expansion was observed.

Journal Article↗

Fat embolization and fatal cardiac arrest during hip arthroplasty with methylmethacrylate.

PURPOSE: This case report describes a cardiac arrest during a cemented hip arthroplasty procedure. Hemodynamic instability during methylmethacrylate use in arthroplasty surgery can be explained by fat embolization rather than the inherent toxicity of the monomer. CLINICAL FEATURES: A 78-yr-old woman required a cemented hemiarthroplasty for a pathologic left subcapital fracture. The patient's past medical history included stable angina, diet-controlled type II diabetes and metastatic breast cancer. During the cementing of the canal and insertion of the femoral prosthesis, desaturation, hypotension and cardiac arrest occurred. The patient underwent a successful intraoperative resuscitation and was transferred to the intensive care unit where she subsequently developed disseminated intravascular coagulopathy. The patient died 24 hr later and autopsy confirmed the cause of death as fat embolization. CONCLUSION: The deleterious cardiovascular effects of methylmethacrylate have been discussed in the literature. However, clinical evidence supports fat embolization during arthroplasty surgery as a greater determinant of hemodynamic compromise. Surgical precautions are paramount in minimizing the sequelae of Bone Implantation Syndrome and anesthetic treatment consists of supportive care.

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