Gamma Radiation Processed Polymeric Materials for High Performance Applications: A Review.

The polymeric properties are tailored and enhanced by high energy radiation processing, which is an effective technique to tune the physical, chemical, thermal, surface, and structural properties of the various thermoplastic and elastomeric polymeric components. The gamma and electron beam radiation are the most frequent radiation techniques used for crosslinking, compatibilizing, and grafting of various polymer blends and composites systems. The gamma radiation-induced grafting and crosslinking are the effective, rapid, clean, user-friendly, and well-controlled techniques for the polymeric materials for their properties improvement for high performance applications such as nuclear, automobile, electrical insulation, ink curing, surface modification, food packaging, medical, sterilization, and health-care in a different environment. Similarly, electron beam radiations crosslinking has been a well-known technique for properties development and has economic benefits over chemical crosslinking techniques. This review focuses on the development of polymeric multi component systems (functionalized polymer, blends, and nanohybrids), where partially nanoscale clay incorporation can achieve the desired properties, and partially by controlled high energy radiations crosslinking of blends and nanocomposites. In this review, various investigations have been studied on the development and modifications of polymeric systems, and controlled dose gamma radiation processed the polymer blends and clay-induced composites. Radiation induced grafting of the various monomers on the polymer backbone has been focused. Similarly, comparative studies of gamma and electron beam radiation and their effect on property devlopment have been focused. The high energy radiation modified polymers have been used in several high performance sectors, including automotive, wire and cable insulation, heat shrinkable tube, sterilization, biomedical, nuclear and space applications.

Thoracoscopic enucleation of oesophageal submucosal tumours in prone position gives excellent long-term outcome: A single-centre experience.

Background: Thoracoscopic enucleation of oesophageal leiomyomas has been adopted by many centres. The procedure when performed in prone position gives good results. The long-term outcome has not been reported earlier. This single-centre study establishes the role of this particular technique. Methods: A retrospective analysis of a prospectively maintained hospital database was performed and after following the study criteria eleven cases of oesophageal submucosal tumours were included in the study. All patients underwent thoracoscopic enucleation in the prone position by a single surgeon. Peri-operative data were recorded and patients followed up for a mean period of 78 months (range = 24-120 months). Results: Thoracoscopic enucleation in prone position was done for all patients with no conversions to an open procedure. Two patients had a mucosal rent during dissection that was repaired. There was no post-operative morbidity greater than Clavien-Dindo Grade 2. Long-term follow-up is available for eight patients (73%) with no recurrence of disease or symptoms. Conclusion: Oesophageal submucosal tumours (predominantly leiomyomas) are benign neoplasms with an indolent biological behaviour and deserve a procedure that would serve the purpose of minimal post-operative morbidity coupled with excellent outcome. Thoracoscopic enucleation in the prone position provides a physiological benefit that translates into better peri-operative outcomes without compromising the long-term outcome and should be the preferred form of treatment for oesophageal submucosal tumours.

Duodenal neuroendocrine tumours in morbidly obese: Amalgamated strategy to optimise outcome.

The association of gastroenteropancreatic neuroendocrine tumours (GEP-NETs) with obesity has been reported and researched on. Rendering of a laparoscopic treatment treating these concurring pathologies in unison has not been described. Two morbidly obese patients with duodenal NETs underwent a resectional procedure, with curative intent, in the form of laparoscopic subtotal gastrectomy with roux-en-y gastrojejunostomy with partial duodenectomy and a laparoscopic one-anastomosis gastric bypass-mini gastric bypass with remnant gastrectomy and partial duodenectomy. Both patients had an uneventful convalescence with acceptable weight loss and no evidence of tumour recurrence on follow-up. The indolent nature of NETs, as compared to the morbidity of obesity provides the rationale for treating this particular cohort of patients with a surgical procedure that would serve to remove the tumour and also provide therapeutic benefit for obesity. With experience in advanced laparoscopic procedures, this can be accomplished safely with acceptable results.

SMA syndrome: management perspective with laparoscopic duodenojejunostomy and long-term results.

BACKGROUND: Superior mesentery artery syndrome (SMAS) is a rare vasculo-anatomic occlusive pathologic entity for which a period of conservative medical management is advocated with surgery reserved for nonresponsive cases. We present our management plan that entails a single admission approach and complete rendering of medical and surgical treatment to the patient on a background of the socioeconomic and cultural trends prevalent in this geographic region. METHODS: A retrospective analysis of 22 cases of SMAS admitted in our health care system who underwent a period of preoperative conditioning followed by laparoscopic duodenojejunostomy from September 2009 to June 2019 was performed. Patients were followed up at regular intervals. RESULTS: The mean follow-up of the cohort was 41.2 months (2-108 months). The median length of stay was 6 days. The mean postoperative stay was 4.13 days. A subgroup of six patients who had severe physiological depletion required a period of preoperative optimisation. Five of the 22 (22.7%) patients suffered from postoperative complications in the form of delayed return of bowel functions. None of the patients had complications more than Clavien-Dindo grade 2 with no mortality. Long-term data are available for 19 patients (86.3%) which showed no symptom recurrence. CONCLUSION: Management of SMAS that entails an antecedent medical therapy followed by surgery can be accomplished in a single admission with good to excellent results in the intermediate and long-term follow-up. Physiologically depleted patients do require a period of intensive preconditioning but on long-term follow-up, they have excellent results.