Koji Teruya

Alveolar epithelial cells: differentiation and lung injury

Abstract:  Re‐epithelialization of alveolar epithelial cells is one of the important repair processes in many types of lung injury. The major functions of alveolar type II cells are synthesis and secretion of surfactant, hyperplasia in reaction to alveolar epithelial injury, and serving as progenitor cells for alveolar type I cells. The authors have examined the effects of several soluble factors on cultured alveolar type II cells in vitro, and also examined the histopathology and gene expression of surfactant proteins in the rat lungs with LPS, bleomycin and/or treated with keratinocyte growth factor. The authors next examined the effects of bone marrow stromal cells (BMSC) implanted transvenously into bleomycin‐induced lungs. The authors found that keratinocyte growth factor (KGF) is a strong growth factor for alveolar type II cells, and that KGF instillation prevents bleomycin‐induced lung injury. Furthermore, the authors showed the possibility of differentiation of implanted BMSC into alveolar epithelial cells. KGF and BMSC may play an important role in maintaining the alveolar epithelium and repairing the damaged epithelium after injury, and may well provide potential therapeutic alternatives.

Vascular hyperpermeability in pulmonary decompression illness: 'the chokes'.

Decompression illness (DCI) develops during or after diving. Pulmonary decompression illness (‘Chokes’) is rarely seen because the affected individual usually dies in the water. We encountered a rare and interesting case. A 60‐year‐old man complained of leg pain after diving. Despite rapid transfer to a nearby hospital, advanced respiratory failure and shock had set in. He was then transferred to our hospital for hyperbaric oxygen therapy (HBOT). On account of his poor general condition, we initially treated him in the intensive care unit without HBOT, where he showed extreme hyperpermeability and a high level of serum procalcitonin (PCT; 20.24 ng/mL). Despite large‐volume fluid therapy, severe intravascular dehydration and shock status remained. We assume that the injured endothelial cells induced vascular hyperpermeability and increased levels of inflammatory cytokines leading to the high serum PCT level. PCT might be a useful stress marker of endothelial damage and severity in DCI, including Chokes.

Unanticipated full stomach at anesthesia induction in a type I diabetic patient with asymptomatic gastroparesis

We encountered a case of unanticipated full stomach at anesthesia induction, despite a 12-h fasting period, in a type I diabetes patient with diabetic neuropathy presenting for elective vitrectomy for proliferative diabetic retinopathy. The patient had ingested seaweed 24 h prior to the surgery, and it was later found in the aspirated gastric content. Gastrointestinal dysfunction due to diabetic neuropathy and the high fiber content of the ingested seaweed are the probable causes of unanticipated full stomach in our case.