Change in Dietary Intake and Nutritional Status Using Mealworms as Hospital Meal in Postoperative Patients

The purpose of this study was to verify the validity of Mealworms as a hospital meal with increased nutrition density. We provided a meal for postoperative patients and conducted analysis of dietary intake and nutritional status of patients and assessment of acceptability of the meal. This study was carried out as a randomized control trial. Patients were supplied either a hospital meal using Mealworms (Experimental group) or a regular hospital meal (Control group). We investigated the administration amounts of parenteral nutrition (PN) and food intake of patients after surgery and measured anthropometry, body composition, and blood tests before surgery and at hospital discharge. We included 34 postoperative patients who were admitted to Gangnam Severance Hospital from March to September. In the groups of patients not supplied with PN, the experimental group (964.68±284.6 kcal, 38.82±12.9 g) had significantly higher dietary calorie and protein intake than the control group (666.62±153.7 kcal, 24.47±4.9 g)(P<0.05). Additionally in the group of patients not supplied with PN, the experimental group (1.37%) showed a significantly higher increase in fat free mass index than the control group (−3.46%)(P<0.05). In all subjects, calorie density and protein density were significantly higher in the experimental group (P<0.001), and acceptability of calorie (P=0.036) and protein (P=0.001) was also significantly higher in the experimental group. Therefore, the results of this study support the validity of the introduction of hospital meals using Mealworms.

Application of Ultrasonic Nano Crystal Surface Modification into Nitinol Stent Wire to Improve Mechanical Characteristics / 의학물리

Phase transformation, superelastic characteristics and variation of surface residual stress were studied for Nitinol shape memory alloy through application of UNSM technology, and life extension methods of stent were also studied by using elastic resilience and corrosion resistance. Nitinol wire of Oslash1.778 mm showed similar surface roughness before and after UNSM treatment, but drawing traces and micro defects were all removed by UNSM treatment. It also changed the surface residual stress from tensile to compressive values, and XRD result showed less intensive austenite peak and clear martensite and additional R-phase peaks after UNSM treatment. Fatigue resistance could be greatly improved through removal of surface defects and rearrangement of surface residual stress from tensile to compressive state, and development of surface modification system to improve not only bio-compatability but also resistance to corrosion and wear will make it possible to develop vascular stent which can be used for circulating system diseases which run first cause of death of recent Koreans.

A Study on Fatigue Characteristic of Stent Using Finite Element Analysis / 의학물리

Stents are frequently used throughout the human body. They keep pathways open in vascular or nonvascular duct for a long time. Therefore its stability is very important factor. In recent years, aconsiderable amount of research has been carried out in order to estimate mechanical properties of the stent such as expansion pressure behavior, radial recoil and longitudinal recoil using FEM (Finite element analyses). However, published works on simulation of stent fatigue behavior using FEM are relatively rare. In this paper, a nonlinear finite-element method was employed to analyses the compression of a stent using external pressure and fatigue behavior. Finite element analyses for the stent system were performed using NASTRAN FX. In conclusion this paper shows how the stent is behaved in the body, and its fatigue behavior.

A Study of Drug Content and Cell Cytotoxicity of Paclitaxel-eluting Stents Coated with Various Biopolymer / 의학물리

In this study, the paclitaxel eluting stent (PES) was prepared by coating a biliary stent with paclitaxel using various biopolymer such as poly (vinyl acetate) (PVAc), poly (lactic-co-glycolic acid) (PLGA), Silicone rubber for restenosis prevention in gastrointestinal disease by a dip-coating method. Drug contents of PES were increased as surface area of stent, concentration and molecular weight of coating polymer increase. In 1H-NMR specta, we know that drug did not change by confirming specific peaks of paclitaxel in PES. As shown in SEM image, PES prepared using various biopolymer is coated clearly and regularly except Silicone rubber coating polymer. In in vitro cell cytotoxicity test, bare stent showed low cytotoxic effect against CT-26 colon carcinoma cell line on 3 day. However, PES coated with PLGA 502H showed the highest cytotoxicity because PLGA 502H is biodegradable polymer and has less molecular weight than other coating polymer. These results suggest that PES coated various biopolymer can be prevented restenosis in gastrointestinal disease.