Israel Medical Association Journal

Background: Tumor necrosis factor is associated with various local and systemic inflammatory sequelae following snakebite. Xanthine oxidase is a principal mediator of remote tissue injury (e.g., lungs, heart, liver).

Objective: To investigate in a snakebite-like animal model the as yet unexplored role of TNF and XO in mediating organ damage following snakebite.

Methods: Sprague-Dawley rats were injected intramuscularly with a non-lethal 500 g/kg dose of Vipera aspis venom (n=10) or saline (n=10). Blood pressure and heart rate were continuously monitored, TNF- was measured in the blood, and total XO + xanthine dehydrogenase activity was assessed in various tissues. Lung histology and permeability indices were analyzed.

Results: Venom injection caused a significant (P0.05) reduction in both heart rate and invasive arterial pressure. The blood circulating TNF levels were significantly higher in the intoxicated group (P0.05 vs. saline group), with changes seen at 30 minutes from intoxication in both groups. Total XO + XDH activity in the kidney, lung and liver of the venom-injected group was significantly (P0.05) higher than in the saline group, while the activity in the heart was similar.

Conclusions: The mediation of remote organ and hemodynamic changes following intramuscular injection of a non-lethal dose of Vipera aspis venom can be attributed partly to TNF and partly to XO. More research is needed to better understand the role of either compound and the time frame of their activity before specific antagonists can be introduced for snakebite management.
 

Background: Exposure of newborn animals to high concentrations of oxygen leads to diffuse alveolar damage similar to that seen in bronchopulmonary dysplasia in human infants. Therefore, neonatal rats are a suitable practical model of hyperoxic lung damage in human infants.

Objective: To determine the involvement of tumor necrosis factor-alpha and interleukin-6 in lung injury in neonatal rats exposed to 100% O2 concentration.

Methods: A randomized controlled study was designed in which litters of term Sprague-Dawley rat pups were assigned to experimental or control groups. The pups in the experimental group were placed in 100% O2 from birth for 9 days, while the control pups were placed in room air. Twelve to 15 pups from each group were sacrificed on day 1, 3, 6, 9 and 13 after birth for bronchoalveolar lavage collection and lung histologic study. The bronchoalveolar lavage fluid was assayed for TNFα and IL-6.

Results: Newborn rats exposed to 100% O2 for the first 9 days of life showed severe pulmonary edema and hypercellularity on days 1 and 3, which then improved to nearly complete resolution on days 6 and 9. Pulmonary TNFα was produced early on O2 exposure (day 3) and pulmonary IL-6 later (days 6 and 9).

Conclusions: Hyperoxia induces sequential production of pulmonary TNFα and IL-6, which corresponds to the severity of the pathological findings and the known inflammatory and anti-inflammatory role of these cytokines.

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TNFα= tumor necrosis factor-alpha

IL-6= interleukin-6

Background: Multiple organ injury in children is an increasingly frequent phenomenon in the modern emergency room. Adrenal hemorrhage associated with this type of trauma has received little attention in the past.

Objectives: Using computed tomography, we sought to determine the rate and nature of adrenal gland injury in children following blunt abdominal trauma due to motor vehicular accident.

Methods: A total of 121 children with blunt abdominal trauma were examined and total body CT was performed in cases of multi-organ trauma or severe neurological injury.

Results: Of all the children who presented with blunt abdominal trauma over a 51 month period, 6 (4.95%) had adrenal hemorrhage. In all cases only the right adrenal gland was affected. Coincidental injury to the chest and other abdominal organs was noted in 66.7% and 50% of patients, respectively.

Conclusions: Traumatic adrenal injury in the pediatric population may be more common than previously suspected. Widespread application of the more sophisticated imaging modalities available today will improve the detection of damage to the smaller organs in major collision injuries and will help in directing attention to the mechanism of trauma.