Can Reinforcement Learning Be Applied to Surgery?

Background: Remarkable progress has recently been made in the field of artificial intelligence (AI).Objective: We sought to investigate whether reinforcement learning could be used in surgery in the future.Methods: We created simple 2D tasks (Tasks 1–3) that mimicked surgery. We used a neural network library, Keras, for reinforcement learning. In Task 1, a Mac OS X with an 8 GB memory (MacBook Pro, Apple, USA) was used. In Tasks 2 and 3, a Ubuntu 14. 04LTS with a 26 GB memory (Google Compute Engine, Google, USA) was used.Results: In the task with a relatively small task area (Task 1), the simulated knife finally passed through all the target areas, and thus, the expected task was learned by AI. In contrast, in the task with a large task area (Task 2), a drastically increased amount of time was required, suggesting that learning was not achieved. Some improvement was observed when the CPU memory was expanded and inhibitory task areas were added (Task 3).Conclusions: We propose the combination of reinforcement learning and surgery. Application of reinforcement learning to surgery may become possible by setting rules, such as appropriate rewards and playable (operable) areas, in simulated tasks

Effect of alternation of kinetic coefficients on step instabilities on Si(0 0 1) vicinal face

金沢大学総合メディア基盤センターWith taking account of alternation of kinetic coefficients, we study the possibility of step instabilities on a Si(0 0 1) vicinal face. In sublimation, a step with large kinetic coefficient recedes faster than that with small kinetic coefficient, and step pairs are formed. The upper side step in the step pair is the step with large kinetic coefficient. An equidistant array of the pairs is unstable against bunching. Number of steps Nmax in bunches increases with time as Nmax ∼ tβ. The exponent β = 0.5 when the bunch grows via successive collisions of step pairs, and β ≈ 1.2 when the bunch grows via coalescence of bunches. © 2007 Elsevier B.V. All rights reserved

Induction of fatty liver by Coleus forskohlii extract through enhancement of de novo triglyceride synthesis in mice

AbstractColeus forskohlii extract (CFE), an herbal ingredient, is used for weight-loss products. CFE's alleged efficacy is attributed to forskolin. However, CFE has been shown to induce fatty liver in mice, with components other than forskolin playing a part in this effect. The present study addressed the underlying mechanism of CFE-induced fatty liver by analyzing changes in CFE-treated mice of lipid concentrations and of the levels of mRNAs encoding enzymes and transcription factors known to be related to fatty liver. Mice were fed a diet containing 0, 0.3 and 1% CFE for 2 weeks. CFE at 1% clearly induced fatty liver, as demonstrated by histological examination and confirmed by increases in triglyceride concentrations in liver. However, treated mice did not exhibit elevation in plasma levels of non-esterified fatty acids. Comprehensive analysis of liver mRNA levels revealed accumulation of multiple transcripts, including mRNAs encoding enzymes acetyl-CoA carboxylase and long-chain elongase; transcription factor peroxisome proliferator-activated receptor gamma (PPARγ); and lipid-droplet-associated fat-specific protein 27 (Fsp27). These findings suggest that the de novo synthesis and accumulation of triglyceride in the liver, through the enhanced expression of specific lipogenic mRNAs, is a major underlying mechanism of fatty liver induction by CFE

Stapled intestinal anastomosis is a simple and reliable method for management of intestinal caliber discrepancy in children

PURPOSE: Popularity of minimally invasive surgeries has led to the development of stapled intestinal anastomosis for adults. The advanced instruments used in this technique are getting suitable with the small intestinal lumens of neonates and infants. We reviewed and compared the intraoperative and postoperative results of stapled and hand-sewn anastomoses in children. METHODS: The operative data of children who underwent stapled and hand-sewn anastomoses between March 2005 and December 2011 were collected and analyzed retrospectively. Furthermore, we compared patients who underwent anastomoses for colostomy closure of anorectal malformation (4 stapled, 9 hand-sewn) and those who underwent anastomoses for treatment of ileal atresia (3 stapled, 11 hand-sewn). RESULTS: In the 47 patients who underwent stapled anastomosis, no intraoperative complications were observed and postoperative complications included wound infection (n = 3), delayed gastric emptying (n = 1), and ileus (n = 1). No complications suggesting anastomotic dilatation were identified. It was observed that patients who underwent stapled anastomosis for colostomy takedown with caliber discrepancy had significantly shorter surgery time than those who underwent hand-sewn anastomosis. CONCLUSION: Our results suggest that stapled anastomosis is safe and effective for various surgical diseases in neonates, infants, and children

The impact of building up the limb muscle mass by the resistance exercise with the intake of milk in middle-aged and elderly women

Background: In the rapidly aging Japanese society, the most serious disorder to prevent is sarcopenia for extending healthy life expectancy. Objective: This study was carried out to clarify whether five kinds of specific and simple resistance exercise performing at home for the short term (42 days) with theintake of whole milk could help to increase the limb muscle mass in middle-aged and elderly women. Participants and measurements: Subjects were 39 healthy women aged 50 to 80 years who gave the consent to participate in the present study. Body composition, physical fitness, food and nutrient intake were measured. Oral glucose-tolerance test (OGTT) was also performed. Groups and results: Subjects were categorized in two groups; Group I with the increase of the limb muscle mass after exercise and Group II with no increase. Body weight before exercise (Group I, 51.6±5.5 kg vs Group II, 58.5±10.3 kg), the body mass index (BMI) (21.7±2.5 kg/m2 vs 24.3±3.9 kg/m2), the limb muscle mass (14.4±1.3 kg vs 15.6±2.0 kg), the skeletal muscle mass index (SMI) (6.0±0.5 kg/m2 vs 6.5±0.7 kg/m2), were all significantly high in Group II. The intake of milk before exercise in Group I (162.1±103.7 g/day) was significantly higher than in Group II (92.5±63.3 g/day). The blood glucose level at 30 min after glucose loading in Group I before exercise was significantly higher than that in Group Ⅱ (199.3 ± 31.1 mg/dl vs 177.0±34.1 mg/dl). Conclusion: The subjects in Group I could successfully increase the limb muscle mass, but the subjects in Group II, whose weight, BMI, the limb muscle mass were significantly high before exercise, could not increase the muscle mass by resistance exercise with the intake of milk. It was considered that the resistance exercise carried out in this study was not strong enough for Group II. We assumed that the BMI value could be the indicator of the strength of exercise for building up the muscle mass in middle-aged and elderly individuals

Selection of Mouse Strains Showing High and Low-incidences of Alloxan-induced Diabetes and Quantitative Morphological Analysis of Langerhan's Islands in Two Strains

ヒト疾患モデル動物を開発する目的で,古くから実験的糖尿病として知られているアロキサン誘発糖尿病をとりあげ,ICR系マウスを選抜基礎集団として,高発症系,低発症系への選抜育種を20代まで継続し,近交系として確立することができた.得られた結果は以下の通りである. 1.選抜20代における発症率は,高発症系で98.9%,低発症系で0%であった.選抜世代に伴う発症率の変化は,高発症系では13代で98.7%,低発症系では7代で0%に達し,それ以後の世代においては一定の範囲内で推移した.本実験で用いたED50値では,両系統とも,すでに選抜限界に達したものと考えられる.また,本実験で採用した兄妹交配法により,選抜20代における両系統の近交係数値は98.6%となり,両系統は近交系として確立された. 2.選抜20代における血糖値は,高発症系で455mg/dl,低発症系で127mg/dl,を示した.選抜世代に伴う血糖値の変化は,高発症系では8代で395mg/dlとなり,それ以後の世代では350～400mg/dl前後の値で推移した.低発症系では7代で128mg/dlとなり,それ以後の世代では120～130mg/dlの範囲内で推移した. 3.近交系として確立された高発症系,低発症系について,膵臓単位面積に占める膵島面積,膵島数,膵島全細胞に占めるβ細胞数の割合などについて定量形態学的検討を加えたが,コントロール区では,低発症系が高発症系に比較して,いずれの測定値についても有意に多く,またアロキサン投与区においても同様の傾向にあることが確認された.以上の結果から,アロキサンに対する感受性の違いで選抜世代を進めてきた高発症系,低発症系が膵臓組織の定量形態学的特性によって特徴づけられてきていることが確認された