Treatment Outcome of Papillary Carcinoma Confined to the Thyroid Isthmus

Objective: The purpose of this study is to evaluate the clinicopathologic characteristics and treatment outcomes of Papillary Thyroid Carcinomas (PTC) of the isthmus and to establish an appropriate surgical strategy. Methods: Thirty-four patients with PTC in isthmus are managed by surgery in National Cancer Center/Cancer Hospital of Chinese Academy of Medical Sciences, Peking Union Medical College from 1985-2008. Demographic data, surgical procedures, pathological features, stages and outcomes are analyzed. Results: Seven patients were men and 27 were women. The median age was 41 years (range, 20 - 71). Twenty-five patients were treated with thyroid isthmusectomy or wide field isthmusectomy, five with hemithyroidectomy (lobectomy and isthmusectomy) and four with hemithyroidectomy and partial resection of the contralateral lobe. Twenty-eight patients had a pathologically T1 lesion (pT1);two patients had a pT2 lesion and four had a pT3 lesion. Five patients (14.7%) had papillary carcinoma detected in one of the pretracheal lymph nodes. Thirty-two patients had a solitary lesion confined to the thyroid isthmus. One patient had two lesions in the thyroid isthmus and another one had two lesions located in the thyroid isthmus and right lobe respectively. With a median follow-up of 94 months (range, 12 - 274), two patients had a recurrence and both survived after a re-operation. There was no regional lymph node or distant organ recurrences. No deaths occurred. Conclusions: Isthmusectomy or wide field isthmusectomy could be a sufficient treatment for PTC confined to the thyroid isthmus. We also recommend that pretracheal lymph node dissection be considered.

Knockout of three aminopeptidase N genes does not affect susceptibility of Helicoverpa armigera larvae to Bacillus thuringiensis Cry1A and Cry2A toxins

Bacillus thuringiensis(Bt)insecticidal toxins have been globally utilized for control of agricultural insects through spraying or transgenic crops.Binding of Bt toxins to special receptors on midgut epithelial cells of target insects is a key step in the mode of action.Previous studies suggested aminopeptidase N1(APN1)as a receptor or putative receptor in several lepidopteran insects including Helicoverpa armigera through evidence from RNA interefence‐based gene silencing approaches.In the current study we tested the role of APNs in the mode of action of Bt toxins using clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR‐associated protein 9‐mediated gene knockout.Three APN genes(HaAPN1,HaAPN2 and HaAPN5)were individually knocked out in a susceptible strain(SCD)of H.armigera to establish three homozygous knockout strains.Qualitative in vitro binding studies indicated binding of Cry1Ac or Cry2Ab to midgut brush border membrane vesicles was not obviously affected by APN knockout.Bioassay results showed that none of the three knockouts had significant changes in susceptibility to Cry1A or Cry2A toxins when compared with the SCD strain.This suggests that the three HaAPN genes we tested may not be critical in the mode of action of Cry1A or Cry2A toxins in H.armigera.