Mera: A scalable high throughput automated micro-physiological system

There is an urgent need for scalable Microphysiological Systems (MPS's)1 that can better predict drug efficacy and toxicity at the preclinical screening stage. Here we present Mera, an automated, modular and scalable system for culturing and assaying microtissues with interconnected fluidics, inbuilt environmental control and automated image capture. The system presented has multiple possible fluidics modes. Of these the primary mode is designed so that cells may be matured into a desired microtissue type and in the secondary mode the fluid flow can be re-orientated to create a recirculating circuit composed of inter-connected channels to allow drugging or staining. We present data demonstrating the prototype system Mera using an Acetaminophen/HepG2 liver microtissue toxicity assay with Calcein AM and Ethidium Homodimer (EtHD1) viability assays. We demonstrate the functionality of the automated image capture system. The prototype microtissue culture plate wells are laid out in a 3 × 3 or 4 × 10 grid format with viability and toxicity assays demonstrated in both formats. In this paper we set the groundwork for the Mera system as a viable option for scalable microtissue culture and assay development.

Endostitch-assisted endoscopic Zenker's diverticulostomy: a tried approach for difficult cases

The aim was to describe a tried approach to endoscopic Zenker's diverticulostomy, especially in those patients with unfavorable anatomy or smaller pouches who may otherwise be relegated to open repair. The study design was a retrospective case series The setting was an urban, tertiary care university medical center There were seven patients, both inpatient and outpatient, with chief complaints of dysphagia. All had a documented Zenker's diverticulum (ZD) on barium swallow. All of the patients were deemed by the primary surgeon to have some anatomic factor that limited exposure of the diverticulum. The patients underwent Endostitch-assisted endoscopic Zenker's diverticulostomy. Records were retrospectively reviewed, including preoperative and postoperative swallowing status, radiographic findings, operative findings, and follow-up results. Seven patients were reviewed, each of whom had successful endoscopic treatment of ZD. Notably, in each case, an anatomical factor precluded the seating of the gastrointestinal anastomosis (GIA) stapler on the cricopharyngeal bar without the use of endoscopic retention sutures. The majority of the patients were discharged on postoperative day one. All but one patient noted a marked improvement in swallowing function immediately following the procedure and at their outpatient follow-up visit. Endoscopic Zenker's diverticulostomy has been well-described and established as a reliable technique in a majority of cases. We report on our experience using a previously described technique specifically for difficult, unfavorable, or contraindicated cases and suggest the employment of this technique as an alternative method to facilitate endoscopic repair and possibly limit the need for an open approach.