Transoral mucosal excision sutured gastroplasty: a pilot study for GERD and obesity with two-year follow-up.

INTRODUCTION: An outpatient transoral endoscopic procedure for gastroesophageal reflux disease (GERD) and obesity would be appealing if safe, effective, and durable. We present the first in human experience with a new system. METHODS: Eight patients with GERD (3) and obesity (5) were selected according to a preapproved study protocol. All GERD patients had preprocedure manometry and pH monitoring to document GERD as well as quality of life and symptom questionnaires. Obese patients (body mass index >35) underwent a psychological evaluation and tests for comorbidities. Under general anesthesia, a procedure was performed at the gastroesophageal junction including mucosal excision, suturing of the excision beds for apposition, and suture knotting. RESULTS: One patient with micrognathia could not undergo the required preprocedural passage of a 60 F dilator and was excluded. The first 2 GERD patients had incomplete procedures due to instrument malfunction. The subsequent 5 subjects had a successfully completed procedure. Four patients were treated for obesity and had an average excess weight loss of 30.3% at 2-year follow-up. Of these patients, one had an 8-mm outlet at the end of the procedure recognized on video review--a correctable error--and another vomited multiple times postoperatively and loosened the gastroplasty sutures. The treated GERD patient had resolution of reflux-related symptoms and is off all antisecretory medications at 2-year follow-up. Her DeMeester score was 8.9 at 24 months. CONCLUSION: The initial human clinical experience showed promising results for effective and safe GERD and obesity therapy.

Mucosal excision and suturing for obesity and GERD.

BACKGROUND: Suture and staple-based endoluminal devices for gastroesophageal reflux disease (GERD) and obesity have failed to demonstrate long-term efficacy. OBJECTIVE: To demonstrate the feasibility of mucosal excision and full-thickness suture apposition of the excision beds to create sufficient scar tissue formation at the gastroesophageal junction for the intraluminal treatment of GERD or obesity. DESIGN: Survival animal experiments. PATIENTS: Seven mongrel dogs. Interventions. Under general endotracheal anesthesia, a Barostat test was performed on 4 dogs. A mucosal excision device was introduced through the esophagus into the proximal stomach. Two to 4 mucosal excisions were performed on all dogs at or just below the gastroesophageal junction and the mucosal pieces were removed. After hemostasis, an intraluminal suturing instrument was introduced and either 2 or 4 sutures were placed through the excision beds to bring them into apposition. These were tied and the suture strands cut. All dogs were survived for 2 months. End-term endoscopies were performed, and a repeat Barostat procedure was performed on the animals undergoing an antireflux procedure. After euthanasia the stomachs were explanted, examined, photographed, and sectioned for histologic examination. RESULTS: All dogs survived without complication. In the 4 GERD dogs, the Barostat studies demonstrated a significant decrease in gastroesophageal junction compliance. In the 3 dogs undergoing the obesity procedure, the gastric outlet apposition to a 6-mm endoscope was satisfactory with full insufflation and the desired scarring was seen on histologic examination. CONCLUSION: It is possible to create adequate gastroesophageal junction scarring for the treatment of GERD and obesity. A clinical pilot study will be initiated.

Application of an end-to-end biomarker discovery platform to identify target engagement markers in cerebrospinal fluid by high resolution differential mass spectrometry.

The rapid identification of protein biomarkers in biofluids is important to drug discovery and development. Here, we describe a general proteomic approach for the discovery and identification of proteins that exhibit a statistically significant difference in abundance in cerebrospinal fluid (CSF) before and after pharmacological intervention. This approach, differential mass spectrometry (dMS), is based on the analysis of full scan mass spectrometry data. The dMS workflow does not require complex mixing and pooling strategies, or isotope labeling techniques. Accordingly, clinical samples can be analyzed individually, allowing the use of longitudinal designs and within-subject data analysis in which each subject acts as its own control. As a proof of concept, we performed multifactorial dMS analyses on CSF samples drawn at 6 time points from n = 6 cisterna magna ported (CMP) rhesus monkeys treated with 2 potent gamma secretase inhibitors (GSI) or comparable vehicle in a 3-way crossover study that included a total of 108 individual CSF samples. Using analysis of variance and statistical filtering on the aligned and normalized LC-MS data sets, we detected 26 features that were significantly altered in CSF by drug treatment. Of those 26 features, which belong to 10 distinct isotopic distributions, 20 were identified by MS/MS as 7 peptides from CD99, a cell surface protein. Six features from the remaining 3 isotopic distributions were not identified. A subsequent analysis showed that the relative abundance of these 26 features showed the same temporal profile as the ELISA measured levels of CSF A beta 42 peptide, a known pharmacodynamic marker for gamma-secretase inhibition. These data demonstrate that dMS is a promising approach for the discovery, quantification, and identification of candidate target engagement biomarkers in CSF.

Anatomy of NOTES gastrotomy in human tissue.

BACKGROUND: Transoral natural orifice translumenal endoscopic surgery (NOTES) procedural success depends on a secure gastrotomy closure. Balloon gastrotomy is the most common technique to date, but the stomach-layer defect sizes and their relationship in human tissue has not been determined. METHODS: Ten 2-cm diameter controlled radial expansion balloon gastrotomies were performed in ex vivo human tissue. All gastrotomies were located on the anterior stomach wall. The main axis of the elliptical-shaped serosal and longitudinal muscle layer opening, the mucosal opening, and the circular muscle layer opening (after removal of mucosa) was measured. All steps were photo documented and electronically analyzed for common opening size. RESULTS: The average common opening was 1 +/- 0.6 to 1.3 cm, although the main axis of a single layer can be as long as 2.2 cm. The average serosal/longitudinal muscle layer defect measured 1.5 cm, the average mucosal defect 1.6 cm, and the average circular muscle layer defect 1.5 cm. CONCLUSION: These findings on NOTES gastrotomy anatomy demonstrate the complexity of the stomach wall opening and the challenge of providing a fail-safe gastrotomy closure. Further in vivo human studies are advised.

Label-free detection of differential protein expression by LC/MALDI mass spectrometry.

Protein abundance changes during disease or experimental perturbation are increasingly analyzed by label-free LC/MS approaches. Here we demonstrate the use of LC/MALDI MS for label-free detection of protein expression differences using Escherichia coli cultures grown on arabinose, fructose or glucose as a carbon source. The advantages of MALDI, such as detection of only singly charged ions, and MALDI plate archiving to facilitate retrospective MS/MS data collection are illustrated. MALDI spectra from RP chromatography of tryptic digests of the E. coli lysates were aligned and quantitated using the Rosetta Elucidator system. Approximately 5000 peptide signals were detected in all LC/MALDI runs spanning over 3 orders of magnitude of signal intensity. The average coefficients of variation for all signals across the entire intensity range in all technical replicates were found to be <25%. Pearson correlation coefficients from 0.93 to 0.98 for pairwise comparisons illustrate high replicate reproducibility. Expression differences determined by Analysis of Variance highlighted over 500 isotope clusters ( p < 0.01), which represented candidates for targeted peptide identification using MS/MS. Biologically interpretable protein identifications that could be derived underpin the general utility of this label-free LC/MALDI strategy.