• Archives of Craniofacial Surgery
• /
• v.22 no.3
• /
• pp.141-147
• /
• 2021

Background: Arteriovenous malformation (AVM) which is a high-blood-flow lesion with connections between arteries and veins without an intervening capillary bed, is difficult to manage. The ear is the second most common site of extracranial AVM. However, studies regarding the management of this condition remain lacking. The purpose of this study was to share managing experiences in our center and to investigate the treatment effect through a retrospective analysis of cases. Methods: Among 265 patients with AVM treated in our vascular anomalies center between January 2008 and January 2021, 10 patients with auricular AVM were included in the study to investigate the lesion distribution, clinical stage, and treatment methods by performing a retrospective evaluation. Results: Among 10 patients, five patients had AVMs distributed in the upper half of the ear, one patient in the lower half of the ear, and four patients in whole ear, respectively. Seven patients had Schobinger stage II, and three had stage III. One patient received surgical treatment only, four patients received sclerotherapy only, and five patients received both surgical treatment and sclerotherapy. The posttreatment status was checked as controlled in two patients, improved in seven patients, persistent in one patient. There were no worsening patients. Conclusion: Auricular AVM is a disease that is difficult to manage by one specific department, thus requiring a collaborative management effort from multidisciplinary team.

• Microbiology and Biotechnology Letters
• /
• v.32 no.2
• /
• pp.101-109
• /
• 2004

In order to enhance the productivity of AVM $B_{la}$ produced by Streptomyces avermitilis as a secondary metabolite, we established a basic protocol necessary for protoplast fusion with high-producing strains as a fusion partner, and then obtained various kinds offusants by adopting a massive strain-development procedure (a miniaturized strain screening system). An alternative fusion method using UV and/or NTG mutation of protoplasts was developed to screen genetic recombinants without specific selectable markers. In this method, the mutants obtained by protoplast fusion after UV and/or NTG treatment (95% death rate) of the respective fusion partner (protoplasts of the respective mutants resistant against L-isoleucine antimetabolites such as O-methylthreonine and/or azaleucine) were regarded as DNA-recombined protoplast fusants. Notably it was demonstrated that most of the protoplast recombinants obtained by the UV mutation method were able to biosynthesize higher amount of AVM $B_{la}$ , reaching almost three times higher level (almost equal to the industrial productivity), compared to the average AVM Bla amount of the parallel mother strains.