No abstract

The newly proposed 15- and 24-loci mycobacterial interspersed repetitive unit (MIRU)-variable-number tandem repeat (VNTR) typing method was evaluated for its ability to differentiate 181 Mycobacterium tuberculosis Beijing family strains. Compared with the original 12-loci MIRU-VNTR typing method, the 15-loci system dramatically improved the discriminatory power for Beijing strains; however, large clusters that could be further differentiated by IS6110 restriction fragment length polymorphism (RFLP) were still obtained. The clonal stability and allelic diversity of a total of 31 VNTR loci were evaluated. VNTRs 3232, 3820, and 4120 were identified as the effective hypervariable VNTR set for the second-line typing of clustered strains following the 15-loci based scheme. Consequently, the discriminatory power of the new scheme (18 loci) equaled that of IS6110 RFLP.

We used 909 strains to compare the population structures of the Mycobacterium tuberculosis Beijing family between different birth-year cohorts in Japan. The results revealed that the spread of a modern sublineage that has high transmissibility is currently increasing, while the spread of an ancient sublineage, STK, has significantly decreased in younger generations.

No abstract

Aortico-pulmonary paraganglioma (APPG) is a rare middle mediastinal tumor. We experienced a case of APPG in a 52-year-old man. Chest computed tomography and magnetic resonance imaging revealed a multi-cystic mass in the subaortic area. A left thoracotomy was performed without definitive preoperative diagnosis. The tumor was strongly adherent to the pericardium and the surrounding large vessels, but a complete resection was undertaken. Histological and immunohistochemical examination revealed that it was a malignant paraganglioma with a microscopically positive surgical margin. After radiotherapy of 50 Gy for the mediastinum, the patient almost recovered from his hoarseness by thyroplasty. We also reviewed nine Japanese cases of APPG reported previously. Though APPG is rare, we must consider that a middle mediastinal tumor may be APPG, and preoperative examination and preoperative planning are necessary to prevent massive bleeding and microscopic residual tumor.