PubMed HealthSearch

Biomedical subjects

G Ray

Publications and source records attributed to G Ray.

At least 37 records · Page 2Linked to original sources

Systems identification scheme for the estimation of the linear viscoelastic properties of the intervertebral disc.

In recent years, traumas due to pilot ejection, automobile accidents, etc., have generated much interest in the biomechanical modelling of the responses of the human spine to high rates of loading. The predicted responses of these models, however, are dependent on the assumed mechanical properties of the discs and vertebrae. The knowledge of these mechanical properties constitute an important aspect of any mathematical model of the spine, i.e., in both quasistatic and dynamic simulations.

Biomechanical Phenomena

A prospective analysis interstitial pneumonia and opportunistic viral infection among recipients of allogeneic bone marrow grafts.

A prospective study of 80 bone marrow transplant recipients with acute leukemia and aplastic anemia employed serial viral cultures, determination of complement-fixing antibody to cytomegalovirus (CMV), and study of material obtained from open lung biopsy and autopsy. There were 43 episodes of interstitial pneumonia, 28 of which were fatal. About 40% of the cases were idiopathic. CMV was the most common candidate pathogen, present in 47% of affected lungs. By a median of 53 days following transplantation, 46% of the recipients were shedding CMV from some site. This event was three times more frequent among recipients who had positive titers of antibody to CMV before transplantation than among seronegative recipients. Failure to respond werologically to CMV infection markedly increased the hazard of dying of interstitial pneumonia. Graft-vs-host disease significantly increased the incidence and lethality of interstitial pneumonia. The presence of leukemia (rather than aplastic anemia) and/or certain factors in the technique of preparation for engraftment may have been significant.

Acute Disease

DHPG effectively treats CMV infection in heart and heart-lung transplant patients: a preliminary report.

Cytomegalovirus (CMV) infection in heart and heart-lung transplant recipients represents a serious if not mortal complication. This study reviews the beneficial effects of 9-(1,3-dihydroxy-2-proproxymethyl) guanine (DHPG), an experimental antiviral agent, in patients with CMV infections. Thirteen of 76 heart and heart-lung transplant patients treated with cyclosporine have developed CMV. Nine of 13 patients developed infections since DHPG has been available. Seven patients received hearts, and two received heart and lungs. Six patients were treated, four heart and two heart-lung recipients; five of six had negative CMV serology before surgery, and all had CMV positive donors. Of the patients not treated, one died at home from disseminated CMV; two had resolution of symptoms and were discharged before the diagnosis was made. In the treated group, three patients had gastrointestinal ulcerative disease, two in the stomach and one in the cecum. The other three patients had CMV pneumonia. DHPG was effective in resolving patient symptoms in five of six patients. The patient who did not respond had a cecal ulcer, multiorgan failure, multiple infections, and died. Two patients with abdominal pain had gastric ulcers that were proved with endoscopy. CMV-induced ulcer disease was diagnosed within 2 hours by fluorescent antibody staining, and resolution was documented by endoscopy. Three patients with CMV pneumonia were treated; two were heart-lung transplant recipients. All started to respond within 72 hours. One heart-lung transplant recipient has had a 9-month course of DHPG because of recurrence of infection when the drug was stopped. The usual dosage was 10 mg/kg/day over 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Acyclovir