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Computer-aided differential diagnosis system for Alzheimer’s disease based on machine learning with functional and morphological image features in magnetic resonance imaging

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Journal of Biomedical Science and Engineering 2013年第11期6卷 1090-1098页

作者： Yasuo Yamashita Hidetaka Arimura Takashi Yoshiura Chiaki Tokunaga ohara tomoyuki Koji Kobayashi Yasuhiko Nakamura Nobuyoshi Ohya Hiroshi Honda Fukai Toyofuku Department of Clinical Radiology Graduate School of Medical Sciences Kyushu University Fukuoka Japan Department of Neuropsychiatry Graduate School of Medical Sciences Kyushu University Fukuoka Japan Division of Radiology Department of Medical Technology Kyusyu University Hospital Fukuoka Japan Faculty of Medical Science Kyushu University Fukuoka Japan Graduate School of Medical Science Kyushu University Fukuoka Japan Division of Radiology Department of Medical Technology Kyusyu University Hospital Fukuoka Japan

Alzheimer’s disease (AD) is a dementing disorder and one of the major public health problems in countries with greater longevity. The cerebral cortical thickness and cerebral blood flow (CBF), which are considered as morphological and functional image features, respectively, could be decreased in specific cerebral regions of patients with dementia of Alzheimer type. Therefore, the aim of this study was to develop a computer-aided classification system for AD patients based on machine learning with the morphological and functional image features derived from a magnetic resonance (MR) imaging system. The cortical thicknesses in ten cerebral regions were derived as morphological features by using gradient vector trajectories in fuzzy membership images. Functional CBF maps were measured with an arterial spin labeling technique, and ten regional CBF values were obtained by registration between the CBF map and Talairach atlas using an affine transformation and a free form deformation. We applied two systems based on an arterial neural network (ANN) and a support vector machine (SVM), which were trained with 4 morphological and 6 functional image features, to 15 AD patients and 15 clinically normal (CN) subjects for classification of AD. The area under the receiver operating characteristic curve (AUC) values for the two systems based on the ANN and SVM with both image?features were 0.901 and 0.915, respectively. The AUC values for the ANN-and SVM-based systems with the morphological features were 0.710 and 0.660, respectively, and those with the functional features were 0.878 and 0.903, respectively. Our preliminary results suggest that the proposed method may have potential for assisting radiologists in the differential diagnosis of AD patients by using morphological and functional image features.

关键词： Computer-aided Classification (CAD) Alzheimer’s Disease Magnetic Resonance Imaging (MRI) Arterial Spin Labeling (ASL) Fuzzy Membership Image Cortical Thickness Cerebral Blood Flow (CBF)

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Preoperative albumin-bilirubin score and liver resection percentage determine postoperative liver regeneration after partial hepatectomy

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World Journal of Gastroenterology 2024年第14期30卷 2006-2017页

作者： Kazuhiro Takahashi Masahiko Gosho Yoshihiro Miyazaki Hiromitsu Nakahashi Osamu Shimomura Kinji Furuya Manami Doi Yohei Owada Koichi Ogawa Yusuke ohara Yoshimasa Akashi Tsuyoshi Enomoto Shinji Hashimoto Tatsuya Oda Department of Gastrointestinal and Hepatobiliary-Pancreatic Surgery University of TsukubaTsukuba 3058-575IbarakiJapan Department of Biostatistics University of TsukubaTsukuba 3058-575IbarakiJapan

BACKGROUND The success of liver resection relies on the ability of the remnant liver to *** of the knowledge regarding the pathophysiological basis of liver regeneration comes from rodent studies,and data on humans are ***,there is limited knowledge about the preoperative factors that influence postoperative *** To quantify postoperative remnant liver volume by the latest volumetric software and investigate perioperative factors that affect posthepatectomy liver *** A total of 268 patients who received partial hepatectomy were *** were grouped into right hepatectomy/trisegmentectomy(RH/Tri),left hepa-tectomy(LH),segmentectomy(Seg),and subsegmentectomy/nonanatomical hepatectomy(Sub/Non)*** regeneration index(RI)and late rege-neration rate were defined as(postoperative liver volume)/[total functional liver volume(TFLV)]×100 and(RI at 6-months-RI at 3-months)/RI at 6-months,*** lower 25th percentile of RI and the higher 25th percentile of late regeneration rate in each group were defined as“low regeneration”and“delayed regeneration”.“Restoration to the original size”was defined as regeneration of the liver volume by more than 90%of the TFLV at 12 months *** The numbers of patients in the RH/Tri,LH,Seg,and Sub/Non groups were 41,53,99 and 75,*** RI plateaued at 3 months in the LH,Seg,and Sub/Non groups,whereas the RI increased until 12 months in the RH/Tri *** to our multivariate analysis,the preoperative albumin-bilirubin(ALBI)score was an independent factor for low regeneration at 3 months[odds ratio(OR)95%CI=2.80(1.17-6.69),P=0.02;per 1.0 up]and 12 months[OR=2.27(1.01-5.09),P=0.04;per 1.0 up].Multivariate analysis revealed that only liver resection percentage[OR=1.03(1.00-1.05),P=0.04]was associated with delayed ***,multivariate analysis demonstrated that the preoperative ALBI score[OR=2.63(1.00-1.05),P=0.02;per 1.

关键词： Liver regeneration Albumin-bilirubin score Liver resection percentage Partial hepatectomy Human Regeneration index

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Automated measurement of three-dimensional cerebral cortical thickness in Alzheimer’s patients using localized gradient vector trajectory in fuzzy membership maps

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Journal of Biomedical Science and Engineering 2013年第3期6卷 327-336页

作者： Chiaki Tokunaga Hidetaka Arimura Takashi Yoshiura tomoyuki ohara Yasuo Yamashita Kouji Kobayashi Taiki Magome Yasuhiko Nakamura Hiroshi Honda Hideki Hirata Masafumi Ohki Fukai Toyofuku Department of Clinical Radiology Graduate School of Medical Sciences Kyushu University Fukuoka Japan Department of Health Sciences Faculty of Medical Sciences Kyushu University Fukuoka Japan Department of Health Sciences Graduate School of Medical Sciences Kyushu University Fukuoka Japan Department of Neuropsychiatry Graduate School of Medical Sciences Kyushu University Fukuoka Japan Division of Radiology Department of Medical Technology Kyushu University Hospital Fukuoka Japan

Our purpose in this study was to develop an automated method for measuring three-dimensional (3D) cerebral cortical thicknesses in patients with Alzheimer’s disease (AD) using magnetic resonance (MR) images. Our proposed method consists of mainly three steps. First, a brain parenchymal region was segmented based on brain model matching. Second, a 3D fuzzy membership map for a cerebral cortical region was created by applying a fuzzy c-means (FCM) clustering algorithm to T1-weighted MR images. Third, cerebral cortical thickness was three- dimensionally measured on each cortical surface voxel by using a localized gradient vector trajectory in a fuzzy membership map. Spherical models with 3 mm artificial cortical regions, which were produced using three noise levels of 2%, 5%, and 10%, were employed to evaluate the proposed method. We also applied the proposed method to T1-weighted images obtained from 20 cases, i.e., 10 clinically diagnosed AD cases and 10 clinically normal (CN) subjects. The thicknesses of the 3 mm artificial cortical regions for spherical models with noise levels of 2%, 5%, and 10% were measured by the proposed method as 2.953 ± 0.342, 2.953 ± 0.342 and 2.952 ± 0.343 mm, respectively. Thus the mean thicknesses for the entire cerebral lobar region were 3.1 ± 0.4 mm for AD patients and 3.3 ± 0.4 mm for CN subjects, respectively (p < 0.05). The proposed method could be feasible for measuring the 3D cerebral cortical thickness on individual cortical surface voxels as an atrophy feature in AD.

关键词： Alzheimer’s Disease (AD) Fuzzy C-Means Clustering (FCM) Three-Dimensional Cerebral Cortical Thickness Localized Gradient Vector

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Serum biomarker tests are useful in delineating between patients with gastric atrophy and normal,healthy stomach

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World Journal of Gastroenterology 2009年第7期15卷 853-859页

作者： Katsunori Iijima Yasuhiko Abe Ryosuke Kikuchi tomoyuki Koike Shuichi ohara Pentti Sipponen Tooru Shimosegawa Division of Gastroenterology Tohoku University Graduate School of Medicine Department of Pathology Helsinki University Central HospitalJorvi Hospital

AIM:To study the value of serum biomarker tests to differentiate between patients with healthy or diseased stomach mucosa:*** with Helicobacter pylori(H pylori)gastritis or atrophic gastritis,who have a high risk of gastric cancer or peptic ulcer ***:Among 162 Japanese outpatients,pepsinogen-(Pg-)and(Pg)were measured using a conventional Japanese technique,and the European GastroPanel examination(Pg and Pg,gastrin-17 and H pylori antibodies).Gastroscopy with gastric biopsies was performed to classify the patients into those with healthy stomach mucosa,H pylori non-atrophic gastritis or atrophic ***:Pg-and Pg assays with the GastroPanel and the Japanese method showed a highly significant *** methodological reasons,however,serum Pg-,but not Pg,was twice as high with the GastroPanel test as with the Japanese *** biomarker assays revealed that 5%of subjects had advanced atrophic corpus gastritis which was also verified by endoscopic *** examination revealed an additional seven patients who had either advanced atrophic gastritis limited to the antrum or antrum-predominant H pylori *** compared to the endoscopic biopsy findings,the GastroPanel examination classified the patients into groups with "healthy" or "diseased" stomach mucosa with 94% accuracy,95% sensitivity and 93% specifi ***:Serum biomarker tests can be used to differentiate between subjects with healthy and diseased gastric mucosa with high accuracy.

关键词：血清标志物检测胃癌患者健康幽门螺杆菌胃炎消化性溃疡疾病萎缩性胃炎 Hpylori 血清PG

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Incidence of reflux esophagitis and Helicobacter pylori infection in diabetic patients

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World Journal of Gastroenterology 2008年第20期14卷 3212-3217页

作者： Ken Ariizumi tomoyuki Koike Shuichi ohara Yoshifumi Inomata Yasuhiko Abe Katsunori Iijima Akira Imatani Tomoyoshi Oka Tooru Shimosegawa Division of Gastroenterology TohokuUniversity Graduate School of Medicine Sendai Miyagi9808574 Japan Division of Diabetes and Metabolic Diseases Tohoku University Graduate School of Medicine Sendai Miyagi 9808574 Japan

AIM: To investigate the incidence of reflux esophagitis (RE) and H pylori infection in the diabetic patient. METHODS: The incidence of RE and H pylori infection were investigated in 85 patients with diabetes mellitus and the results were compared with controls. RESULTS: The incidence of RE in diabetic patients was 17.6%. Although this tended to be higher in diabetic patients, there were no statistically significant differences between diabetic patients and controls. The incidence of H pylori infection in diabetic patients was 53.7% but no statistically significant difference was seen between diabetic patients and controls in the incidence of H pylori infection. CONCLUSION: No significant differences could be seen between diabetic patients and controls in the incidence of RE and H pylori infection.

关键词：糖尿病食管炎幽门螺杆菌细菌感染

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Identification of the layered morphology of the esophageal wall by optical coherence tomography

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World Journal of Gastroenterology 2009年第35期15卷 4402-4409页

作者： Satoshi Yokosawa tomoyuki Koike Yasushi Kitagawa Waku Hatta Kaname Uno Yasuhiko Abe Katsunori Iijima Akira Imatani Shuichi ohara Tooru Shimosegawa Division of Gastroenterology Tohoku University Graduate School of Medicine1-1Seiryo-machiAoba-kuSendai Miyagi 980-8574Japan

AIM:To assess each layer of the optical coherence tomography(OCT)image of the esophageal wall with reference to the histological structure. METHODS:Resected specimens of fresh pig esophagus was used as a model for the esophageal *** injected cyanoacrylate adhesive into the specimens to create a marker,and scanned them using a miniature OCT *** localization of these markers was assessed in the OCT *** we compared the OCT-imaged morphology with the corresponding histological section,guided by the cyanoacrylate adhesive *** prepared a second set of experiments using nylon sutures as markers. RESULTS:The OCT image of the esophageal specimen has a clear five-layered morphology. First,it consisted of a relatively less reflective layer; second,a more reflective layer;third,a less reflective layer;fourth,a more reflective layer;and fifth,a less reflective *** the OCT images with marked histological sections showed that the first layer corresponded to stratified squamous epithelium; the second to lamina propria;the third to muscularis mucosa;fourth,submucosa;and fifth,muscularispropria with deeper structures of the esophageal ***:We demonstrated that the OCT image of the normal esophageal wall showed a five- layered morphology,which corresponds to histological esophageal wall components.

关键词：形态鉴定断层扫描光学相干氰基丙烯酸酯胶粘剂食道标记定位组织结构组织切片

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Brain activity following esophageal acid infusion using positron emission tomography

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World Journal of Gastroenterology 2010年第43期16卷 5481-5489页

作者： Shigeyuki Kobayashi Yasuhiko Abe Manabu Tashiro tomoyuki Koike Katsunori Iijima Akira Imatani Shuichi ohara Satoshi Watanabe Shin Fukudo Tooru Shimosegawa Division of Gastroenterology Tohoku University Graduate School of Medicine Division of Cyclotron Nuclear Medicine Cyclotron and Radioisotope Center Tohoku University Division of Behavioral Medicine Tohoku University Graduate School of Medicine

AIM: To investigate symptoms and brain activity following esophageal acid infusion. METHODS: Fifteen healthy volunteers were recruited for the study. Hydrochloric acid (pH 1 and 2) and distilled water (pH 7) were randomly and repeatedly infused into the esophagus. The brain activity was evaluated by positron emission tomography. The severity of heartburn elicited by the infusion was rated on an auditory analog scale of ***: The severity of heartburn following each infusion showed a step-wise increase with increasing acidity of the perfusate. The heartburn scores were significantly higher in the second pH 1 infusion compared with the first infusion. Acid and distilled water infusion induced activation of various brain areas such as the anterior insula, temporal gyrus, and anterior/ posterior cingulate cortex. At pH 1 or 2, in particular, activation was observed in some emotion-related brain areas such as the more anterior part of the anterior cingulate cortex, parahippocampal gyrus, or the temporal pole. Strong activation of the orbitofrontal cortex was found by subtraction analysis of the two second pH 1 infusions, with a significant increase of heartburn symptoms. CONCLUSION: Emotion-related brain areas were activated by esophageal acid stimulation. The orbitofrontal area might be involved in symptom processing, with esophageal sensitization induced by repeated acid stimulation.

关键词： Esophageal acid infusion Brain imaging Positron emission tomography

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Effect of BNT162b2 mRNA COVID-19 vaccine on sperm morphokinetics and DNA integrity: A prospective observational study in Japan

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Asian pacific Journal of Reproduction 2023年第2期12卷 58-63页

作者： Yasuhiro ohara Shimpei Mizuta Hidehiko Matsubayashi Tomomoto Ishikawa Tsuyoshi Takiuchi Tadashi Kimura Department of Reproductive Medicine Reproduction Clinic Osaka4-20Ofuka-choKita-kuOsakaJapan Department of Obstetrics and Gynecology Graduate School of MedicineOsaka University2-15YamadaokaSuita CityOsakaJapan Department of Reproductive Medicine Reproduction Clinic Tokyo1-5-2Higashi-shinbashiMinato-kuTokyoJapan Department of Clinical Genomics Graduate School of MedicineOsaka University2-15YamadaokaSuita CityOsakaJapan

Objective:To assess whether the coronavirus disease 2019(COVID-19)mRNA vaccine affects sperm morphokinetics using a computer-assisted semen analyzer and other semen parameters using a sperm chromatin structure ***:Healthy male volunteers in two Japanese clinics between May 2021 and December 2021 were prospectively *** donated sperm twice,two days apart,in the following phases:before vaccination,2 weeks after the first vaccine dose,and 2,4,and 12 weeks after the second *** sperm parameters,sperm motility characteristics,and the percentage of DNA-damaged sperm were compared among the different ***:Ninety-six semen samples from ten volunteers,who were vaccinated with the BNT162b2 mRNA vaccine,were *** were no significant differences between any phases in basic semen findings and parameters of the sperm chromatin structure *** sperm motion characteristics,the average linear velocity,beat-cross frequency,and sperm motility index significantly decreased after the second vaccine dose(P=0.018,P=0.003,and P=0.027,respectively),with no significant differences between any two phases by post-hoc pairwise ***:After COVID-19 mRNA vaccination,while sperm motion characteristics might fluctuate,no apparent deterioration of basic sperm parameters or sperm DNA integrity was *** the adverse effects of COVID-19 on sperm,our findings suggest that there might be no reason to refrain from vaccination for healthy individuals.

关键词： Computer-assisted semen analyzer COVID-19 vaccine Flow cytometry Male fertility Sperm chromatin structure assay

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Pain in Non-Athlete Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement and Hip Labral Tears: A Longitudinal Study

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Health 2023年第9期15卷 990-1002页

作者： Kaori Sano Yuko Uesugi Hidetsugu ohara Graduate School of Health Sciences Kobe University Kobe Japan Department of Nursing Kinjo Gakuin University Nagoya Japan Department of Orthopedic Surgery Hirakata City Hospital Hirakata Japan

Background: Pain in patients with orthopedic problems is an important aspect of surgical evaluation. However, the effect on the quality of life depends not only on the degree of pain but also on its type. Hip arthroscopy has been performed for hip joint symptoms caused by femoroacetabular impingement (FAI) and hip labrum tears. However, the degree and type of pain after hip arthroscopy remains unknown. Objective: This study aimed to clarify the degree and type of pain during 6 months after hip arthroscopy. Methods: Non-athlete patients aged 20 - 65 years who underwent hip arthroscopy between December 2018 and October 2019 participated in a questionnaire survey before hospitalization and at 1, 3, and 6 months after surgery. The questionnaire comprised the Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ) for quality of life, International Physical Activity Questionnaire (IPAQ) for activities, and the Short-Form McGill Pain Questionnaire (SF-MPQ-2) for pain. Results: The analysis included 10 patients (men: 4, women: 6, mean age: 38 ± 8.6 years, FAI: 6 cases, hip labrum tears: 4 cases). The average time from symptom onset to surgery was 26.9 ± 19.0 months. The analysis from before surgery to 6 months after surgery showed improvement over time in all scale scores (JHEQ, IPAQ, and SF-MPQ-2). The degree of pain was significantly improved based on the JHEQ visual analog scale evaluation (P = 0.019) 3 months after surgery. Significant improvement in intermittent pain (P = 0.011) based on SF-MPQ-2 was noted 3 months after surgery;however, no significant improvement in continuous pain was noted. Conclusions: Patients who underwent hip arthroscopy showed significant improvements in the degree of pain and type of intermittent pain from before surgery to 3 months after surgery, however, no change was observed in continuous pain.

关键词： Hip Arthroscopy Orthopedic Quality of Life Type of Pain

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计算机口语在线练习系统对日语习得的影响 ——以日语专业大学生的自主学习为例

计算机口语在线练习系统对日语习得的影响 ...

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作者： ohara Shoran 华东师范大学

学位级别：硕士

在学习者自主学习的过程中,计算机在线口语学习系统为其提供了宝贵的口语练习机会。然而,该线上系统对日语习得中输入、输出的影响仍缺乏定量研究,另外,虽有许多研究探讨了教师在自主学习过程中的反馈,如纠错和鼓励等,但几乎都是采用定... 详细信息

在学习者自主学习的过程中,计算机在线口语学习系统为其提供了宝贵的口语练习机会。然而,该线上系统对日语习得中输入、输出的影响仍缺乏定量研究,另外,虽有许多研究探讨了教师在自主学习过程中的反馈,如纠错和鼓励等,但几乎都是采用定性方法研究其对学习者语言习得的影响。本研究以中国日语专业基础阶段学习者为对象,定量调查分析了“自主学习中使用计算机在线口语练习系统进行长期持续的口语练习对学习者自主学习意识产生的影响”。同时,本研究还依托于开发的口语练习系统,定量调查并探讨了在为期13个月的自主学习中,“长期持续的线上口语练习”以及“对自主口语练习的纠错与激励等反馈形式”对输入及口语特征变化的影响。问卷调查结果显示,在进行自主口语练习时,相较于在现实中面对面的方式,学习者使用计算机在线口语练习系统时会更加放松。另外,没有证据表明长期持续的口语练习会对学习者的自主学习策略和自主学习时间产生影响。对输入和口语特征的定量研究显示,在自主学习过程中,根据学习者的认知水平而研发的在线口语练习促进了学习者的输入理解,且对输出也产生较大的影响。实验过程中还观察到了学习者的一些行为,如:以插图和照片为线索聆听旁白讲解、查询语句含义和语法意思、自主查询和学习单词以便使用日语表达自己的想法等等。研究结果表明,长期持续的自主口语练习不仅可以帮助学习者促进输入、提升口语,还可以满足其挑战自我口语能力、进行与自身认知水平相符的口语练习的需求。另外,研究还提供了一种新视角,即对于处于语言习得基础阶段的学习者来说,他们处理的语言信息并不局限于基础阶段学习的“基础水平”,而可以是高于现阶段语言能力涉及思维能力的问题。从反馈形式看,与教师对学生的鼓励相比,口语纠错反馈对输入和输出产生了消极影响。这可能是因为,纠错反馈加重了学习者的焦虑,其负面影响超过了学习者根据纠错自我修正语言错误所产生的正面影响。对于自主学习者来说,纠错反馈本来只是为学习者个人定制的一种学习信息。如果想让学习者有效地利用纠错反馈,需要做的是帮助学习者将思维方式从他人决策型学习转变为自我决策型学习。在中国大学日语专业教育中,由于考虑到学习者的语言水平,基础阶段的输出仅限于简单的交流,而激发好奇心和培养思维能力的学习互动往往被推迟到高年级阶段。在自主学习过程中持续引进符合学习者认知水平的在线口语练习,有助于学习者的日语习得提升,进而有利于在早期阶段导入培养学习者思维能力的讨论活动。在该过程中,教师首先应当增强学习者的信心和动力,鼓励他们积极使用目标语言进行表达,而非只进行纠错反馈。

关键词：自主学习在线口语学习系统输入输出纠错反馈

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