ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Serial circulating endotoxin measurements (quantitative chromogenic limulus assay) were performed in sera from 19 burned patients to determine the profile of circulating serial circulating endotoxin after burn and the effect of early wound excision on serial circulating endotoxin level. Results indicate an early endotoxemia with the peak serial circulating endotoxin levels 7 to 12 hours and 4 days after burn. More importantly, the level of circulating serial circulating endotoxin can be diminished by early excision; late wound excision was associated with a transient increase of serial circulating endotoxin level. Early excision, therefore, may play a critical role in limiting endotoxemia after burn injury.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Concentrations of the interleukin-2 receptor are significantly elevated in serum after burn injury. To examine the immunoregulatory potential of this molecule, suppressive activity of sera from patients with major burns (n=16; 40% to 80% total body surface area) was assessed before and after immunoaffinity adsorption with interleukin-2. The preadsorption level of interleukin-2 receptor in the pooled serum after burn injury was 6250 U/ml. This serum demonstrated a strong suppressive activity, inhibiting expression of cellular interleukin-2 receptor and proliferative responses of normal human lymphocytes to alloantigen and exogenous interleukin-2 by 60% to 90%. Adsorption of pooled serum after burn injury with interleukin-2 lowered the level of interleukin-2 receptor to 1800 U/ml and reduced its immunosuppressive activity. The percentage of interleukin-2 receptor-bearing cells, and cell proliferative responses, increased by 50% to 70% compared with sham adsorbed pooled serum after burn injury. Thus serum interleukin-2 receptor after burn injury may represent a specific mediator for downregulation of interleukin-2—dependent responses.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Burn patients often exhibit prolonged cell-mediated immune suppression. Of the mechanisms proposed to account for this, one invokes an inability on the part of T lymphocytes to undergo blastogenesis, clonal expansion, and differentiation—a process partially mediated by interleukin-2. Triplicate samples of 10% dilutions of burn serum from nine burn patients (three with >60% burn) were analyzed for their ability to suppress mitogen-induced lymphocyte blastogenesis. A separate aliquot of stimulated cultured lymphocytes was tagged with a monoclonal antibody to interleukin-2 receptors. The serum of patients with >60% burn was significantly more suppressive (as measured by depressed tritiated thymidine incorporation by cultured lymphocytes) than that taken from patients with smaller burns. In addition, serum from those with larger burns caused a marked reduction hi the interleukin-2 receptor—labeling index, suggesting that it possesses factor(s) that directly or indirectly block T lymphocyte interleukin-2 receptor expression.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The ability of polymorphonuclear leukocytes to kill bacteria and yeast is reflected by cellular chemiluminescence or similary by the production of H2O2during oxidative metabolism. With the use of flow cytometry and 2'7'dichlorodihydrofluorescein-diacetate, we determined the direct effect of thermal injury and the indirect effect of burn serum on murine polymorphonuclear leukocyte oxidative metabolism after stimulation on days 1, 5, and 10 after 25% total body surface area burn. Control or burn peritoneal leukocytes and 10% control or burn serum were incubated in vitro with 2'7'dichlorodihydrofluorescein-diacetate for 15 minutes, then stimulated with phorbol 12-myristate 13-acetate. The change in polymorphonuclear leukocyte fluorescence was calculated from fluorescence histograms before and after stimulation. The oxidative metabolism of burn polymorphonuclear leukocytes was clearly depressed on days 5 and 10 after burn injury. Control polymorphonuclear leukocytes in the presence of day 5 burn serum produced decreased levels of H2O2, returning to normal by day 10. In general, bactericidal activity is markedly depressed on days 5 and 10 after thermal injury and may be associated with increased risk of sepsis.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Four strains ofPseudomonas aeruginosashowed significant variation in the elaboration of the virulence-associated exoproducts, exotoxin A and proteases. These variations appeared to affect the mortality observed when these strains were used to infect burned mice. Further, these variations seemed to influence the efficacy of individual after sepsis treatments designed to (1) reduce total microbial load in the host (HIg treatment), (2) reduce total circulating protease load in the host (α1-PI treatment), or (3) neutralize the specific effects of exotoxin A (antitoxin treatment). Combined treatment, using all of these approaches, was significantly better than individual treatment.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Candida albicansdissemination through the gastrointestinal tract was examined in mice given a thermal injury, immunosuppressive therapy, or both. After gastrointestinal tract colonization widiC.albicans, mice were initially subjected to a 20% total body surface area, full-thickness, dorsal scald burn.Only one mouse in the burned group (5%) had evidence ofC.albicansin the liver at the time the mice were killed. No dissemination was observed in sham-burned animals. When mice were immunosuppressed with cyclophosphamide, an increased incidence of gastrointestinal tract dissemination was noted in burned (31%) and sham-burned (23%) mice; however, only 3 days after burn was there a significant difference in dissemination between burned and sham-burned mice (p< 0.02). This corresponded to the day of severest neutropenia in response to cyclophosphamide treatment. The results of the study indicate thatC.albicanscan disseminate from the gastrointestinal tract in response to thermal injury, but a significant suppression of the immune response must occur for the event to be commonplace.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The effect of in vivo administration of the immunomodulator TP-5 on the in vitro synthesis and release of C3, PGE2, and TXB2by guinea pig alveolar, splenic, and peritoneal macrophages was studied. Three groups of animals were studied: unburned control, burned, and burned +TP-5. There was no significant difference in the production of C3, PGE2, or TXB2by alveolar macrophages of the three groups of animals or by splenic macrophages of the three groups. There was a significant difference in the production of TXB2by peritoneal macrophages between the unburned control compared with the burned and burned plus TP-5 groups. Our conclusion is that peritoneal macrophages seem to be controlled by mechanisms that are different from those that control alveolar or splenic macrophages.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Skin equivalents containing allogeneic fibroblasts in a collagen matrix and overlaid with isologous epidermal cells have been successfully grafted to rodents. By contrast, skin equivalents containing isologous fibroblasts and allogeneic epidermal cells provoke a strong rejection response, characterized by the infiltration of mononuclear cells into the epidermis at 1 week and occlusion of the microvasculature and destruction of the epidermis by lymphocytes 2 weeks after grafting. Based on these findings, skin equivalents containing allogeneic fibroblasts could be used in the treatment of burn injuries, but the epidermis should be obtained from the patient.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Although the risk of nosocomial transmission of human immunodeficiency virus remains low, burn center personnel may be at greater risk. Approximately 10% of burn patients admitted to an urban center were found to be positive to the human immunodeficiency virus, consistent with other findings of increased prevalence in trauma patients. “Universal” precautions adequate for. other health care settings may not be sufficient in the burn center. Knowledge of a patient's human immunodeficiency virus status has important treatment implications.

ISSN:0273-8481    

出版商:OVID    

年代:1989

数据来源: OVID