Peroral endoscopic myotomy for the treatment of achalasia after failed pneumatic dilation.

BACKGROUND AND AIMS: POEM is a rescue endoscopic therapy for patients who had previously failed surgical or endoscopic treatment. However, data regarding its effectiveness after failed pneumatic dilation (PD) and its long-term effects are limited. We aimed to retrospectively investigate the long-term outcomes in patients who had undergone POEM after failed PD. METHODS: Data from 66 achalasia patients with a 2-year follow-up period were analyzed. Intraprocedural events were compared between the first POEM group (patients without prior-endoscopic intervention) and prior PD group (patients who had pre-POEM PD). Symptom evaluation, HRM and 24 h-pH DeMeester scores between the two groups were performed at 2 years after the POEM procedure. Muscularis externa samples were obtained from the lower esophagus using POEM to assess the muscle fibrosis with Azan-Mallory staining. RESULTS: POEM was successfully performed for all achalasia patients. During the 2-year follow-up period, the success rate of POEM was 96.15% (25/26) for patients with prior PD and 95% (38/40) with primary POEM. For patients with type II achalasia and who underwent prior PD, the post-procedure DeMeester score was higher compared to patients who underwent POEM only (P < 0.05). A larger number of patients who underwent primary POEM (27.50%, 11/40) complained of mild heartburn compared to patients who underwent POEM after PD (7.69%, 2/26) (P < 0.05). With regards to fibrosis, the majority of patients who underwent POEM only were classified as F-1 (45.00%, 18/40), while the majority of patients who underwent prior PD were classified as F-2 (42.3%, 11/26). The degree of fibrosis was significantly different between the two groups (P < 0.05). Both surgical time and prior PD were correlated with the degree of fibrosis (P < 0.05). CONCLUSIONS: Despite the technical challenges, pre-POEM endoscopic treatment does not impact the safety and efficacy of POEM in achalasia patients. Longer follow-up studies using larger cohorts are needed to determine long-term outcomes and complications of POEM.

Characterization of an Ecdysteroid-Regulated 16 kDa Protein Gene in Chinese Oak Silkworm, Antheraea pernyi (Lepidoptera: Saturniidae).

A large number of ecdysteroid-regulated 16 kDa proteins (ESR16s) of insects have been isolated and annotated in GenBank; however, knowledge on insect ESR16s remain limited. In the present study, we characterized an ecdysteroid-regulated 16 kDa protein gene isolated in Chinese oak silkworm, Antheraea pernyi Guérin-Méneville ('ApESR16' in the following), an important silk-producing and edible insect. The obtained cDNA sequence of ApESR16 is 1,049 bp, harboring an open reading frame of 441 bp that encodes a polypeptide of 146 amino acids. CD-search revealed that ApESR16 contains the putative cholesterol/lipid binding sites on conserved domain Npc2_like (Niemann-Pick type C-2) belonging to the MD-2-related lipid-recognition superfamily. Sequence comparison revealed that ApESR16 exhibits 51-57% identity to ESR16s of lepidopteran insects, 36-41% identity to ESR16 or NPC2a of nonlepidopteran insects, and 28-32% identity to NPC2a of vertebrates, indicating a high sequence divergence during the evolution of animals. Phylogenetic analysis found that the used sequences were divided into two groups corresponding to vertebrates and invertebrates, and the used insect sequences were also well clustered according to their families. The A. pernyi ESR16 mRNA is expressed during all four developmental stages and in all tested tissues. Injection of 20-hydroxyecdysone (20-E) into A. pernyi diapausing pupae triggering diapause termination induced upregulation of ESR16 mRNA compared to the diapausing pupae, with the highest expression level at day 2 in the ovaries but day 12 in the fat body. Our results suggested that ApESR16 might be a diapause-related gene and plays a vital role in the pupal diapause of A. pernyi.