Efficacy and safety of cold forceps biopsy for diminutive pharyngeal neoplasms: Single-center, prospective pilot study.

BACKGROUND: Management of diminutive pharyngeal neoplasms is controversial. Thus, we conducted a single-center, prospective pilot study to investigate the efficacy and safety of endoscopic excision with cold forceps biopsy (CFB) of these lesions. PATIENTS AND METHODS: Thirty-nine lesions endoscopically diagnosed with narrow-band imaging as pharyngeal neoplasms of 3 mm or smaller were excised with CFB using jumbo biopsy forceps (cap diameter 2.8 mm, jaw volume 12.4 mm3 ). The primary outcome was endoscopically determined local remnant/recurrence rate 3 months after CFB. The secondary outcomes were histopathologically determined local remnant/recurrence rate; risk factors associated with the endoscopic remnant/recurrence; and incidence of intraoperative or delayed bleeding and other adverse events. RESULTS: Histological diagnosis of the 39 CFB-excised lesions were: 11 high-grade dysplasia (28.2%), 22 low-grade dysplasia (56.4%), two basal cell hyperplasia (5.1%) and four atypical squamous epithelium (10.3%).Twenty-seven patients (30 lesions) underwent follow-up endoscopy 3 months after CFB; the endoscopic and pathological local remnant/recurrence rate was 20% (6/30; 95% confidence interval (CI), 7.7-36.6%) and 16.7% (5/30; 95% CI, 5.6-34.7%), respectively. Location of the lesion in the hypopharynx was a significant risk factor associated with the endoscopic local remnant/recurrence (P = 0.049). No significant adverse events occurred. CONCLUSIONS: Cold forceps biopsy with jumbo biopsy forceps appears to be a safe and effective technique for excising diminutive pharyngeal neoplasms. Although small, the excised lesions may have a remarkably high frequency of high-grade dysplasia. (Clinical trial registration number: UMIN000037980).

Self-fusion and fusion cell isolation of transformants derived from white rot fungus Phanerochaete sordida YK-624 by simple visual method.

In order to develop a simple method for crossing two transformants, we first attempted to elucidate the fusion type (self-compatibility or -incompatible) of Phanerochaete sordida YK-624. Two transformants expressing green or red fluorescent protein derived from an auxotrophic mutant were constructed. Each recombinant protein fluoresced by expression as a fused protein with glyceraldehyde-3-phosphate dehydrogenase. On co-culture of both transformants, a number of sequential hyphal cells emitting dual fluorescence were formed at the contact areas of both hyphae. Some of the single cells isolated as protoplasts and chlamydospore from the co-cultures also expressed these fluorescent proteins. These results suggest that P. sordida YK-624 possesses a self-compatible fusion system. In addition, transformant strains with different fluorescence derived from this fungus can readily undergo self-fusion and nuclear interchange events by confrontational and mixed cultivation, and we developed a simple method that allows fused cells to be isolated as chlamydospores.

Direct lactic acid production from beech wood by transgenic white-rot fungus Phanerochaete sordida YK-624.

A lactic acid (LA)-producing strain of the hyper-lignin-degrading fungus Phanerochaete sordida YK-624 with the lactate dehydrogenase-encoding gene from Bifidobacterium longum (Blldh) was constructed. When the endogenous pyruvate decarboxylase gene-knocked down and Blldh-expressing transformant was cultured with beech wood meal, the transformant was able to successively delignify and ferment the substrate. Supplementation of calcium carbonate into the culture medium, significantly increased the level of LA accumulation. Direct LA production (at 0.29g/l) from wood was confirmed, and additional inclusion of exogenous cellulase in this fermentation yielded significant further improvement in LA accumulation (up to 1.44g/l). This study provides the first report of direct production of LA by fermentation from woody biomass by a single microorganism, and indicates that transgenic white-rot fungi have a potential use for development of simple/easy applications for wood biorefinery.