Erratum: Rhinitis in children less than 6 years of age: current knowledge and challenges

[This corrects the article on p. 115 in vol. 1, PMID: 22053307.].     

An unexpected tumor causing right ventricular obstruction

A 58‐year‐old male with a history of a soft tissue sarcoma in remission presented with a 2 weeks history of progressive dyspnea. Transthoracic echocardiography showed right ventricular dilation; right ventricular systolic pressure (RVSP) of 110 mm Hg, and a lobulated mass in the right ventricular outflow tract (RVOT) causing obstruction. Microbubble contrast was administered showing perfusion within the mass, which suggested malignancy. A CT pulmonary angiogram (CTPA) confirmed the presence of the mass in the RVOT without evidence of pulmonary embolism. This case demonstrates the importance of the multimodality imaging approach for the differential diagnosis of masses in the RVOT.     

Heinz Bodies Formed in Erythrocytes by Fatty Acid Ozonides and Ozone

Ozonides of the methyl esters of oleic, linoleic, linolenic and arachidonic acids were found to produce Heinz body inclusions in human and mouse erythrocytes. No simple relationships between structure and activity were noted.

Concomitant with Heinz body formation, methemoglobin and loss of cellular thiols were observed. Methyl ozonides readily oxidized glutathione and 1 mole of oxidized glutathione was formed per mole of methyl oleate ozonide. Methyl ozonides catalyzed the formation of disulfide-linked interchain polymers between hemoglobin and ovalbumin. Heinz bodies were not produced with ozone in the absence of unsaturated lipids. Heinz bodies were observed in the blood of mice exposed to ozone (0.85 ppm) for 48 hours.

These observations suggest that fatty acid ozonides could serve as a toxic chemical species formed on ozone inhalation and could explain the divergent protective effects of lipid antioxidants and thiol generating systems in vivo.     

Advances in 4D radiation therapy for managing respiration: Part I – 4D imaging

Techniques for managing respiration during imaging and planning of radiation therapy are reviewed, concentrating on free-breathing (4D) approaches. First, we focus on detailing the historical development and basic operational principles of currently-available “first generation” 4D imaging modalities: 4D computed tomography, 4D cone beam computed tomography, 4D magnetic resonance imaging, and 4D positron emission tomography. Features and limitations of these first generation systems are described, including necessity of breathing surrogates for 4D image reconstruction, assumptions made in acquisition and reconstruction about the breathing pattern, and commonly-observed artifacts. Both established and developmental methods to deal with these limitations are detailed. Finally, strategies to construct 4D targets and images and, alternatively, to compress 4D information into static targets and images for radiation therapy planning are described.