The characteristics of knife tool marks retained on hard tissues can be used to outline the shape and angle of a knife. The purpose of this study was to describe such marks on bone tissues that had been chopped with knives. A chopping stage with a gravity accelerator and a fixed bone platform was designed to reconstruct the chopping action. A digital microscope was also used to measure the knife angle (θ) and retained V-shape tool mark angle (ψ) in a pig skull. The κ value (elasticity coefficient; θ/ψ) was derived and recorded after the knife angle (θ) and the accompanied velocity were compared with the proportional impulsive force of the knife and ψ on the bone. The constant impulsive force revealed a correlation between the V-shape tool mark angle (ψ) and the elasticity coefficient (κ). These results describe the tool marks--crucial in the medicolegal investigation--of a knife on hard tissues.
Rationale:
Denatonium benzoate is a useful indicator to ensure that the respirator being used by an individual forms a tight enough seal to adequately protect against unwanted airborne exposure. Although the relative risk for adverse effects of fit testing using denatonium benzoate is low, the absolute number of workers with adverse reactions may nevertheless be sizeable.
Patient concerns:
A 34-year-old female nurse rapidly developed shortness of breath, cough, and agitation after denatonium benzoate fit testing. She had a history of allergy to shrimp, crab, mite, and disinfecting products (containing quaternary ammonium).
Diagnoses:
Due to typical symptoms of asthma after exposure to denatonium benzoate aerosol without any other apparent cause, serial pulmonary function tests indicating obstructive lung function and a higher concentration of immunoglobulin antibody E, she was diagnosed with allergic asthma.
Interventions:
This patient was treated with omalizumab (Xolair), corticosteroid, β
2
agonist, montelukast, and Symbicort turbuhaler.
Outcomes:
The patient showed quick responses after treatment with diphenhydramine (intramuscularly), fenoterol HBr (inhalation), and prednisolone (oral). Approximately 2 weeks later, she suffered from difficulty breathing and asthmatic symptoms again when she was exposed to polished wax and disinfectant. She was treated with omalizumab (Xolair), corticosteroid, β
2
agonist, montelukast, and Symbicort turbuhaler. The patient was in stable condition with improvement in symptoms during follow-up.
Lessons:
There may be potentially important health risks when healthcare workers are exposed to denatonium benzoate. Individuals who have a history of allergy to disinfecting products (containing quaternary ammonium) should avoid exposure of denatonium benzoate. More advanced research is needed in the future.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.