Biomedical subjects

L L Ketch

Publications and source records attributed to L L Ketch.

8 recordsLinked to original sources

PubMed1994

Trauma primes cells.

Trauma induces many dramatic and complex changes in host cellular response. This complexity arises from the constellation of signals induced by stress, infection, and injury. Cellular priming, defined as altered response to an agonist induced by an antecedent stimulus, appears to be operative after trauma. If the interaction between two signalling pathways is such that one augments (or depresses) the other, subsequent stimulation of the second "primed" pathway can result in an exaggerated (or attenuated) response. Thus, trauma can prime cells in either a constructive or destructive fashion. Receptor stimulation by priming agents results in the activation of receptor-specific cell signalling pathways. These intracellular signalling pathways can "crosstalk" modifying each other in either a positive of negative fashion. The positive or negative character of interpathway crosstalk eventually manifests itself physiologically as constructive or destructive priming. Could the characteristics of the initial priming predict the sense of the final cellular message? Although the magnitude of both the priming stimulus and subsequent stimuli are important, the temporal relationship between the two stimuli as well as the positive or negative character of their interacting signal pathways need to be considered. It is unclear whether any one characteristic alone determines the sense of the priming effect. In general, it is the interaction of two stimuli with a cell at all three levels (magnitude, character, and temporal relationship) that dictates the final cellular response.

Animals↗

PubMed1993

Pressure sores.

Explore the source record for details and available documents.

Humans↗

PubMed1989

Aeromonas hydrophila infection complicating digital replantation and revascularization.

Two cases of thumb replantation and one of finger revascularization complicated by Aeromonas hydrophila infection are reported. Two digits were lost because of infection in soft tissue and osteomyelitis. One thumb had extensive necrosis. In all cases the infection was difficult to eradicate, probably because of ischemia. All three patients sustained their injuries while cutting meat or fish. These infection sources have not been previously reported. Note is made of Aeromonas hydrophila in medicinal leeches that are used in microvascular surgery and the potential for iatrogenic infection.

Accidents, Occupational↗

PubMed1988

Management of associated soft-tissue injury.

Initially, soft-tissue injuries associated with vascular trauma require management according to the general surgical principles of wound care. Antimicrobial prophylaxis should be instituted. The mechanism and extent of injury must be determined, and debridement and irrigation should be completed in the operating room with the intent to preserve vital structures, decrease bacterial contamination, and render the wound free of devitalized tissue. Prompt coverage of exposed vascular repairs is vital in order to minimize the chance for infection and to protect the repair from desiccation and subsequent trauma. Early primary closure of heavily contaminated wounds can have disastrous results. Therefore, questionable wounds should be managed by delayed primary closure after repeated irrigation and debridements, with the definitive decision as to the timing of wound closure being based on quantitative cultures. The plastic and reconstructive surgeon can aid the vascular surgeon in the primary or secondary closure of such wounds by bringing healthy, vascularized muscle to cover the vascular repair. Vascularized muscle has proved superior in the coverage and healing of contaminated wounds. If conditions permit, this can be most readily accomplished by transfer of local muscle. Musculocutaneous flaps are of special value in cases that require increased durability or where extended coverage is necessary. With either of these flap techniques, the surgeon must be thoroughly familiar with the anatomy, blood supply, and function of the local muscles. Free-tissue transfer is to be utilized when local tissue is severely damaged in a way that precludes the use of adjacent muscle or myocutaneous flaps. Strict adherence to the principles and techniques of microsurgery, thorough evaluation of the zone of injury and recipient blood vessels, and understanding of the principles governing local muscle transfer are essential for a successful outcome.

Bacterial Infections↗

PubMed1983

Surgical correction of the fat neck.

This is an up-to-date review of the state of the art in the treatment of the fat neck at the University of Miami School of Medicine, based on twenty-five years of experience including several thousand cases. The combination of submental lipectomy, platysma myectomy, facelift, submandibular lipectomy, platysma myotomy, and posterior muscle traction with suture fixation has consistently produced marked improvement in the fat neck. Under this regimen, when the patient returns in five to ten years for a second lift, it is rare that the neck requires more than the skin tightening that comes with a simple facelift.

Adipose Tissue↗

PubMed1980

Surgical implications of Behçet's disease.

Behcet's disease, though originally described as a triad of oral and genital aphthous ulcers and inflammatory ocular lesions, has had several new elements added to its description. The updated syndrome now includes gastrointestinal (GI) involvement as well as polyarthritis, neuritis, myocarditis, and glomerulonephritis. Of particular importance to the surgeon are the GI manifestations that include hemorrhage and perforation. A review of the literature indicates that the GI manifestations of Behcet's disease are not uncommon and, though usually mild, may necessitate surgical intervention. Our experience with a patient with GI hemorrhage and subsequent perforation underlines the occasional urgent complications of this disease.

Adult↗

PubMedDate not supplied

Healing characteristics of expanded autografts on wounds covered with homograft and Biobrane temporary wound dressing.

This study compared the healing characteristics of expanded autografts on wounds with interstices that were closed with cryopreserved cadaver homograft split-thickness skin and wounds with interstices that were closed with the synthetic skin substitute, Biobrane temporary wound dressing. Nine paired wounds in four patients with large burns were used in this study. When Biobrane temporary wound dressing adhered to a wound, epithelial migration did not proceed until it was removed. Although wounds covered with homograft immediately had the appearance of healed wounds, biopsy specimens showed evidence of a delay in epithelial migration. Although these results indicate impaired epithelial migration with the use of both materials, we concluded that homograft offered an advantage because the wounds that were covered with it remained closed during the entire reepithelialization process.

Adult↗

PubMedDate not supplied

WEB2170, a specific platelet-activating factor antagonist, attenuates neutrophil priming by human serum after clinical burn injury: the 1991 Moyer Award.

Primed neutrophils may contribute to endothelial and end-organ damage after burn injury because of increased endothelial adherence and enhanced toxic oxygen metabolite generation in response to a "second insult" such as bacterial sepsis. The purposes of this study were to determine: (1) whether serum from patients with thermal injury causes priming of the neutrophil NADPH:O2 oxidoreductase, (2) whether time after burn (early vs late) influences neutrophil priming, and (3) whether priming could be attenuated by a specific platelet-activating factor antagonist, WEB2170. Normal human neutrophils were incubated with 10% sera that was obtained from healthy adult controls (normal human sera) and with 10% sera from patients with greater than 30% total body surface area burns, which was collected early (early postburn sera) (i.e., between 12 and 48 hours after burn) or late (late postburn sera) (5 to 15 days, after burn). Priming of the neutrophil oxidase was tested for by measurement of the generation of superoxide anion after a stimulus of 10(-6) mol/L formyl-methionine-leucine-phenylalanine (fMLP). In separate experiments, neutrophils were pretreated with WEB2170 before serum incubation and fMLP stimulation to block any priming that may be mediated by platelet-activating factor. All sera caused an increased rate of superoxide anion production in response to fMLP and thus "primed" the neutrophil NADPH:O2 oxidoreductase. Greater priming occurred after incubation with late postburn sera than with other sera. WEB2170 completely inhibited priming by normal human sera and early postburn sera and partially inhibited priming by late postburn sera.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗