ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

Burn injury and intradermal injection of bradykinin or histamine cause permeability changes visualized as dye-release lesions in the skin of guinea pigs injected intravenously with Evans blue dye. Antihistamine pretreatment ablates the histamine but not the effect of thermal injury or bradykinin. Bradykinin is generated via activation of Hageman factor in a two-step reaction. Steps 1 and 2 can be inhibited by corn trypsin inhibitor and soy bean trypsin inhibitors, respectively. Dye-release lesions were reduced from thermal injury and bradykinin injections when these substances were injected into the skin first. Angiotensin-converting enzyme deactivates bradykinin by degrading it. Angiotensin-converting enzyme inhibitor neutralizes angiotensin-converting enzyme. Dye-release lesions from both thermal injury and bradykinin injection were enhanced because of continued bradykinin build-up when these treatments were preceded by subcutaneous injections of angiotensin-converting enzyme inhibitor. Thus bradykinin is generated in thermal injury via the Hageman factor-dependent pathway. Hageman factor sits at the apex of a series of interrelated cascade systems, all of which impinge on the animal's immune status. Uncontrolled Hageman factor activation in thermal injury may be the link among all the events collectively known as the “post thermal injury immunosuppression syndrome.”

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

Cultured human keratinocytes are used for skin grafts, but their success is limited by late graft loss. Development of antibody to fetal bovine serum (FBS) protein used in culture media for in vitro keratinocyte growth has been identified. The persistence of FBS antigen in skin grafts is important in the induction of the immune response and the susceptibility of the keratinocytes to immune-mediated injury. The magnitude and longevity of FBS protein persistence on human keratinocytes was studied. Secondary passage human keratinocytes were grown in media supplemented with 5% FBS. The media was changed to one supplemented with pooled human AB serum, and the amount of FBS protein incorporated in the tissue was measured over the following 8 days by an ELISA reaction directed against FBS antigen. Incorporated FBS antigen decreased for the first 3 days to 31% of maximum. There was no further significant decrease for 5 days. Keratinocytes grown in alternative serum supplements (NuSerum [Collaborative Research Inc., Bedford, Mass.] and Serum Plus [Hazelton Research Products Inc., Lenexa, Kan.]), which contain reduced amounts of FBS, offered no significant reduction in FBS protein incorporation. This duration of antigen persistence would make human keratinocytes susceptible to cell destruction by immune response to FBS and may contribute to delayed loss of human keratinocyte grafts.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

The effects of inhalation injury on the pulmonary microvascular fluid flux and bronchial blood flow were examined in a long-term study of sheep (N= 13). They were insufflated with either 48 breaths of cotton smoke (n= 8) or air (n= 5) while they were deeply anesthetized with halothane. After injury, anesthesia was discontinued and the animals were mechanically ventilated throughout the experimental period (24 hours). Bronchial blood flow increased significantly at all time points recorded and reached its peak 20 minutes after the inhalation trauma (11 ± 1 ml/hr to 106 ± 18 ml/hr;p< 0.05). Thereafter, bronchial blood flow decreased to a value that was six to eight times above the baseline measurement for the remainder of the study period. With these changes in blood flow, there was a concomitant increase in lung lymph flow. This variable gradually increased and was 633% of the baseline value (6 ± 1 ml/hr to 44 ± 8 ml/hr) 24 hours after the challenge with smoke. The control animals showed little or no change in cardiopulmonary function during the experimental period. There is no correlation between the increase in bronchial blood flow and lung lymph flow patterns after cotton smoke inhalation injury.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

Electrical burns or ischemia (induced by vascular ligation) were produced in the legs of 15 anesthetized dogs to study evolution of tissue changes compared with impedance alterations. After the application of 1-ampere currents at 60 Hz, animals were monitored from 1 to 4 days. Muscle impedance was measured with frequency sweeping to determine tissue destruction. Nuclear magnetic resonance spectroscopy (phosphorus 31) was used to assess metabolic activity, and results were compared to impedance measurements. In burned limbs, 70% reduction in muscle impedance was seen, which corresponds to decreased metabolic activity (absent organic phosphates) and suggests necrosis. Visually viable tissue had impedance decreases of 25% and levels of organic phosphates slightly lower than normal. Relaxation frequencies in dogs with severe burns exceeded 80 kHz; in viable tissue, 30 to 40 kHz (normal: 30 kHz). In ischemic muscle, organic phosphates decreased rapidly (1 to 2 hours); impedance changes evolved more slowly (1 day), but they ultimately reached the same degree of severity. Measurement of impedance may be a valuable adjunct in the evaluation of electrical burns, since significant changes strongly suggest nonviability.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

Aluminum contaminates various fluids that are used in intravenous therapy, and it is associated with bone disease and encephalopathy. Albumin is highly contaminated with aluminum, which is eliminated primarily by renal excretion. Patients with burns receive large quantities of albumin and have impaired renal function, which puts them at hypothetical risk for aluminum loading. To assess the risk of aluminum loading we analyzed sera from 12 patients with burns for aluminum concentrations. Serum aluminum concentration was elevated in 8 of the 12 patients, and levels were at or near toxicity in 3 of the 8. Serum aluminum and serum creatinine levels directly correlated,r= 0.71 andp< 0.005. No relation was found between serum aluminum and amount of albumin received. However, patients with the highest serum aluminum levels were the most severely burned and none survived. Thus patients with burns who are receiving albumin are at risk for aluminum loading. Impaired renal function contributes to aluminum retention.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

The early pulmonary hypertension seen with endotoxin (lipopolysaccharide) has been reported as resulting from the release of thromboxane A2. We studied the cardiopulmonary response to endotoxin in sheep with and without treatment with a thromboxane synthetase inhibitor, OKY-046. The animals were implanted with instruments for crystallographic dimension analysis of the left ventricle and measurement of left ventricular, aortic, left atrial, and pulmonary arterial pressures and cardiac index. Thirteen sheep received 1.0 μg/kg ofEscherichia coliendotoxin with (n= 6) and without (n= 7) OKY-046 (10 μg/kg bolus, then 10 μg/kg/min). OKY-046 prevented the increase in pulmonary arterial pressure and decrease in cardiac index usually seen during the early phase of endotoxemia. Between 8 and 12 hours after the administration of endotoxin, cardiac index increased from 6.4 ± 0.8 to 8.4 ± 0.8 L/min/m2. Concomitantly, the end-systolic pressure/diameter relationship (a sensitive myocardial contractility index) significantly decreased from 14.7 ± 0.6 to 7.7 ± 0.7 mm Hg/mm. Another index of the left ventricular contractility, the maximum rate of pressure rise was also reduced. OKY-046 prevented decreases in end-systolic pressure/diameter relationship and maximum rate of pressure rise.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

Composite skin grafts of xenodermis or allodermis with a thin split-thickness isograft overlay were evaluated for stability and contraction. Male inbred Lewis rats were used as recipients, with Buffalo rats serving as allogeneic dermis donors. Cryopreserved human skin was used for xenodermis grafts. The two components of the composite graft, the xenodermis or allodermis and the isograft overlay, were grafted in one operation to a surgically created wound. Wounds were observed for 1 year. The composite skin grafts took fairly well, although spotty loss of the overlaid isograft was noted. The xenodermis and allodermis remained grossly intact even at 1 year after grafting. However, composite skin grafts in this animal model contracted more than did sheet isografts alone.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

In our society, we take for granted the ability to travel with few restrictions. For most travelers, the major factor that limits travel is cost. However, for a significant number of Americans, the phrase “freedom to travel” is meaningless. These are the physically handicapped, a group with special needs that has long been denied what every American assumes to be a natural right.

ISSN:0273-8481    

出版商:OVID    

年代:1990

数据来源: OVID