PePIF1, a P-lineage of PIF-like transposable element identified in protocorm-like bodies of Phalaenopsis orchids.

BACKGROUND: Orchids produce a colorless protocorm by symbiosis with fungi upon seed germination. For mass production of orchids, the prevailing approaches are both generation of protocorm-like bodies (PLBs) from callus and multiplication of adventitious buds on inflorescence. However, somaclonal variations occur during micropropagation. RESULTS: We isolated the two most expressed transposable elements belonging to P Instability Factor (PIF)-like transposons. Among them, a potential autonomous element was identified by similarity analysis against the whole-genome sequence of Phalaenopsis equestris and named PePIF1. It contains a 19-bp terminal inverted repeat flanked by a 3-bp target site duplication and two coding regions encoding ORF1- and transposase-like proteins. Phylogenetic analysis revealed that PePIF1 belongs to a new P-lineage of PIF. Furthermore, two distinct families, PePIF1a and PePIF1b, with 29 and 37 putative autonomous elements, respectively, were isolated, along with more than 3000 non-autonomous and miniature inverted-repeat transposable element (MITE)-like elements. Among them, 828 PePIF1-related elements were inserted in 771 predicted genes. Intriguingly, PePIF1 was transposed in the somaclonal variants of Phalaenopsis cultivars, as revealed by transposon display, and the newly inserted genes were identified and sequenced. CONCLUSION: A PIF-like element, PePIF1, was identified in the Phalaenopsis genome and actively transposed during micropropagation. With the identification of PePIF1, we have more understanding of the Phalaenopsis genome structure and somaclonal variations during micropropagation for use in orchid breeding and production.

Transoral laser marsupialization of epiglottic cysts.

OBJECTIVE: The objective of this study is to investigate the safety and effectiveness of laser marsupialization of epiglottic cysts via a transoral route. STUDY DESIGN: A prospective clinical series. METHODS: Twenty-eight consecutive patients with epiglottic cyst underwent laser marsupialization of an epiglottic cyst via a transoral approach. Pre- and postoperative laryngoscopic examinations were carried out. RESULTS: A total of 28 patients were enrolled, including 19 males and 9 females, ranging in age from 38 to 69 years, with a mean age of 54 years. Among these patients, 23 had a lumpy throat, and the remaining 5 had a voice alternation. The diameters of the cysts ranged from 1 to 3 cm. No perioperative bleeding or airway swelling was noted in any patient. The postoperative follow-up period ranged from 4 to 41 (mean, 16) months. No recurrence was found during the follow-up examinations. CONCLUSION: Transoral laser marsupialization is a simple, safe, and effective method for treatment of epiglottic cysts. This procedure has the potential to serve as the treatment of choice in the management of this condition.

Paraganglioma presenting as chronic otitis media with cholesteatoma: pitfalls and strategies.

The coexistence of paraganglioma with cholesteatoma is a very rare clinical disorder. The clinical presentations are nonspecific. There may be radiological characteristics of either cholesteatoma or paraganglioma in the middle ear area, but the diagnosis of the coexistence of the 2 is usually made only postoperatively. Here is such a case that is made more interesting not only because it initially presented with conductive hearing loss but also because the clinical picture mimicked chronic otitis media. The patient underwent postauricular tympanomastoidectomy with extended facial recess approach to remove the tumor. No evidence of recurrence and complications were noted.