Metal vs plastic stents for preoperative biliary drainage in patients with periampullary cancer: An updated systematic review and meta-analysis.

BACKGROUND/PURPOSE: Metal stents (MS) are recommended for preoperative biliary drainage (PBD) in patients with periampullary cancer, but whether MS are superior in terms of re-intervention and direct cost is debatable. This study aimed to compare the effects of MS and PS on the outcomes of patients with periampullary cancer. METHODS: For this random-effects meta-analysis, electronic databases were screened for randomized controlled trials (RCTs) published until January 2022. Subgroup analyses were performed basis on the center type and presence of NAC. RESULTS: In this meta-analysis, seven RCTs (440 participants) were included. MS reduced re-interventions (risk ratio [RR] = 0.42, 95% confidence interval [CI] = 0.25-0.72) and direct costs (mean difference = -474 USD, 95% CI = -656 to -292). PBD-related complications (RR = 0.74, 95% CI = 0.32-1.71) and postoperative complications (RR = 0.73, 95% CI = 0.45-1.17) did not differ between MS and PS. Compared PS, MS reduced postoperative complications in high-volume centers (RR = 0.64, 95% CI = 0.49-0.84) and PBD-related complications in patients receiving NAC (RR = 0.29, 95% CI = 0.08-1.08). CONCLUSIONS: Metal stents likely reduces re-interventions and direct costs. Further studies are needed to confirm the effects of MS on the outcomes.

A newly developed bioartificial pancreas successfully controls blood glucose in totally pancreatectomized diabetic pigs.

Construction of a safe and functional bioartificial pancreas (BAP) that provides an adequate environment for islet cells may be an important approach to treating diabetic patients. Various types of BAP devices have been developed, but most of them involve extravascular implantation of islets in microcapsules or diffusion chambers. These devices have poor diffusive exchange between the islets and blood, and often rupture. To overcome these problems, we developed a new type of BAP composed of polyethylene-vinyl alcohol (EVAL) hollow fibers that are permeable to glucose and insulin and a poly-amino-urethane-coated, non-woven polytetrafluoroethylene (PTFE) fabric that allows cell adhesion. Porcine islets attached to the surface of the PTFE fabric, but not to the surface of the EVAL hollow fibers, allowing nutrient and oxygen exchange between blood flowing inside the fibers and cells outside. We inoculated this BAP with porcine islets and connected it to the circulation of totally pancreatectomized diabetic pigs. We found that blood glucose levels were reduced to a normal range and general health was improved, resulting in longer survival times. In addition, regulation of insulin secretion from the BAP was properly controlled in response to glucose both in vitro and in vivo. These results indicate that our newly developed BAP may be a potential therapy for the treatment of diabetes in humans.

PuraMatrix facilitates bone regeneration in bone defects of calvaria in mice.

Artificial bones have often used for bone regeneration due to their strength, but they cannot provide an adequate environment for cell penetration and settlement. We therefore attempted to explore various materials that may allow the cells to penetrate and engraft in bone defects. PuraMatrix is a self-assembling peptide scaffold that produces a nanoscale environment allowing both cellular penetration and engraftment. The objective of this study was to investigate the effect of PuraMatrix on bone regeneration in a mouse bone defect model of the calvaria. Matrigel was used as a control. The expression of bone-related genes (alkaline phosphatase, Runx2, and Osterix) in the PuraMatrix-injected bone defects was stronger than that in the Matrigel-injected defects. Soft X-ray radiographs revealed that bony bridges were clearly observed in the defects treated with PuraMatrix, but not in the Matrigel-treated defects. Notably, PuraMatrix treatment induced mature bone tissue while showing cortical bone medullary cavities. The area of newly formed bones at the site of the bone defects was 1.38-fold larger for PuraMatrix than Matrigel. The strength of the regenerated bone was 1.72-fold higher for PuraMatrix (146.0 g) than for Matrigel (84.7 g). The present study demonstrated that PuraMatrix injection favorably induced functional bone regeneration.

Endoscopic removal of a denture with clasps impacted in the ileocecum.

We report a case of endoscopic removal of a denture with clasps impacted in the ileocecum. The patient was a 63-year-old man hospitalized at another center with aspiration pneumonia. He had a history of cerebral bleeding, inflicted permanent damage with left hemiplegia, and dysphagia. Abdominal radiography for localization of a catheter in the femoral vein revealed a denture in the right lower quadrant of the abdomen. He was subclinical and could not recall when he might have swallowed the denture. The patient was brought by ambulance to our institution. Computed tomography showed a foreign body with the density of metal in the ileocecum without any severe complications such as obstruction or perforation. Following intestinal lavage from a nasogastric tube, we performed colonoscopy and successfully retrieved the denture. The patient showed no complications associated with endoscopic therapy and returned to the previous hospital 3 days after endoscopic removal of the denture.