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T M Murphy

Publications and source records attributed to T M Murphy.

99 records · Page 6Linked to original sources
PubMed1969

Immunochemical and enzymatic comparisons of the tryptophan synthase alpha subunits from five species of Enterobacteriaceae.

The reactive surface structures of alpha subunits of tryptophan synthase from Escherichia coli, Shigella dysenteriae, Salmonella typhimurium, Aerobacter aerogenes, and Serratia marcescens were compared by measuring (i) their reactivities in micro-complement-fixation assays with antibodies directed specifically to E. coli wild-type alpha subunit, (ii) their reactivities in enzyme neutralization assays with the same antibodies, and (iii) their binding affinities for tryptophan synthase beta(2) subunits. The enzymes from the four heterologous species cross-reacted in the microcomplement-fixation assays with the anti-E. coli alpha subunit antibodies, each to a different degree. However, neutralization titers of the antibodies reacting with the various alpha subunits were comparatively similar, and the beta(2) subunit-binding and -stimulating abilities of the alpha subunits were even more closely alike. The results suggested that the tertiary structure of the beta(2) subunit-binding site of the alpha subunit has been conserved, relative to the rest of the molecule, during the evolutionary divergence of the species of Enterobacteriaceae.

Antigen-Antibody Reactions↗
PubMedDate not supplied

Early reversal of postoperative hypoxemia.

Peridural analgesia was combined with the respiratory-stimulant effect of doxapram for intermittent hyperinflation of the lungs to reverse early postoperative (PO) hypoxemia following inhalation anesthesia for upper abdominal operations. Twenty unpremedicated men undergoing upper abdominal operations were studied for 5 hours in the recovery room. Ten of these patients received doxapram plus peridural analgesia; the other 10, doxapram plus morphine analgesia. Rectal temperature, PaO2, PaCO2, respiratory rate, exhaled minute ventilation (VE), tidal volume (VT), and blood pressure and pulse were measured. The mean increase from control for VE was 9.6 L/min and for VT, 356 ml/breath during doxapram therapy for the morphine group. Corresponding values for the peridural group were 14.4 L/min for VE and 660 ml/breath for VT. Mean PaO2 for the morphine group decreased significantly from the corresponding preoperative value (p less than 0.005). Lack of significant change between preoperative and PO values for PaO2 for the peridural group would indicate that under the conditions of this study, early PO hypoxemia can be reversed by the combination of peridural analgesia with doxapram therapy.

Adult↗
PubMedDate not supplied

Chronic opioids for chronic low back pain--solution or problem?

The article by Brown et al does not provide data to justify long-term opioid use but does suggest a treatment option for the many patients who have chronic back pain and who want the help that our medical delivery system often does not provide. Having worked in a tertiary referral pain clinic that serves many low back pain patients who have demonstrated the ineffectiveness of chronic opiate therapy, I am strongly ambivalent about recommending prescribing ongoing opioiod therapy for chronic pain patients. The caveats about prescribing opioids for such patients are most appropriate (i.e., do not prescribe opioids for those who have a history of problems with opioid therapy or for whom increased intake is associated with decreased function); however, for patients who do not display these problems (and there could be many out there), I am sympathetic with the sentiments expressed by Brown et al. A trial of these drugs might be warranted if all else fails and continued therapy with opioids seems justified, but only with zealous attention to monitoring function and therapeutic compliance, as outlined by the authors. With regard to the doses needed for control, the method of opioid administration might be important, that is, whether it is in tablets or in a masking vehicle. In this day of open dialogue, it is not fashionable to blind the patient to the drug or dose, but I believe blinding has a place in the care of a particular group of patients whose symptom (pain) can vary considerably with time. I have found that most chronic pain patients rarely, if ever, reduce their analgesic intake in better times, but an attentive physician can if masking vehicles are used. Thus the physician can limit the amount of drug consumed long term. In my personal experiences with comparable chronic nonmalignant pain patients (albeit in different hemispheres), the average opioid maintenance (methadone) dosage was halved by prescribing the drug in a masking vehicle rather than as a tablet. If pain complaints are reduced and if function is improved according to the record (eg, patient is working) and the relatives' report, and if you, the prescribing physician, are happy, then a long-term regimen of opioid therapy is probably fine. Further controlled trials are needed to see whether this therapy works, and if so, what are the optimal agent(s) and dosages, what is optimal monitoring, and most important of all, who is the optimal patient who might derive not only analgesia but also functional benefit rather than compromise from this therapy. If we cannot make patients better, we must not make them worse.

Analgesics, Opioid↗