RESUMEN
BACKGROUND: Although superior vena cava (SVC) syndrome has also been reported as a late complication of pacemaker (PM) implantation, acute onset of SVC syndrome caused by disdialysis syndrome in patients with PM implantation is very rare. There are no specific therapies or guidelines. CASE SUMMARY: A 96-year-old woman receiving dialysis was implanted with a PM due to sick sinus syndrome. She was referred to our facility for chest discomfort experienced during dialysis. Upon examination, unilateral pleural effusion on the right side was cloudy with a foul odour. The patient was diagnosed with pyothorax and treated with antibiotics. After the effusion was reduced, it gradually reaggravated and remained cloudy. In this case, SVC syndrome, which is generally considered a late complication after PM implantation, rapidly developed following the bacteraemia, resulting in impaired venous return, chylothorax, and disdialysis syndrome. After catheter intervention for SVC stenosis, the patient's symptoms promptly improved. The patient has been recurrence-free for a year. CONCLUSION: Acute SVC syndrome can cause dysdialysis in PM-implanted patients. Catheter intervention alone has improved this condition for a traceable period.
RESUMEN
Radiation therapy for head and neck cancers is frequently associated with adverse effects on the surrounding normal tissue. Irreversible damage to radiation-sensitive acinar cells in the salivary gland (SG) causes severe radiation-induced xerostomia (RIX). Currently, there are no effective drugs for treating RIX. We investigated the efficacy of treatment with conditioned medium derived from stem cells from human exfoliated deciduous teeth (SHED-CM) in a mouse RIX model. Intravenous administration of SHED-CM, but not fibroblast-CM (Fibro-CM), prevented radiation-induced cutaneous ulcer formation (p < 0.0001) and maintained SG function (p < 0.0001). SHED-CM treatment enhanced the expression of multiple antioxidant genes in mouse RIX and human acinar cells and strongly suppressed radiation-induced oxidative stress. The therapeutic effects of SHED-CM were abolished by the superoxide dismutase inhibitor diethyldithiocarbamate (p < 0.0001). Notably, quantitative liquid chromatography-tandem mass spectrometry shotgun proteomics of SHED-CM and Fibro-CM identified eight proteins activating the endogenous antioxidant system, which were more abundant in SHED-CM than in Fibro-CM (p < 0.0001). Neutralizing antibodies against those activators reduced antioxidant activity of SHED-CM (anti-PDGF-D; p = 0.0001, anti-HGF; p = 0.003). Our results suggest that SHED-CM may provide substantial therapeutic benefits for RIX primarily through the activation of multiple antioxidant enzyme genes in the target tissue.
