123 research outputs found
流体構造連成とモード同定による多自由度翼列フラッター解析の研究
学位の種別: 課程博士審査委員会委員 : (主査)東京大学教授 渡辺 紀徳, 東京大学教授 金子 成彦, 東京大学教授 鈴木 宏二郎, 東京大学准教授 寺本 進, 東京大学准教授 姫野 武洋University of Tokyo(東京大学
Anatomical Risk Factors for Reintervention after Arterial Switch Operation for Taussig–Bing Anomaly
Background: This study aimed to determine the factors related to reintervention, especially for pulmonary artery stenosis (PS), in patients with Taussig–Bing anomaly (TBA) after arterial switch operation (ASO).
Methods:This retrospective study included 34 patients with TBA who underwent ASO between 1993 and 2018. Preoperative anatomical and physiological differences and long-term outcomes were determined using a case-matched control with transposition of the great arteries (TGA) with ventricular septal defect (VSD) and TBA with an anterior and rightward aorta.
Results: The median age and body weight at ASO were 43 (16–102) days and 3.6 (2.8–3.8) kg, respectively. Aortic arch obstruction and coronary anomalies were present in 64% and 41% patients, respectively. The hospital mortality rate was 11%, including one cardiac death, and late mortality rate was 2.9%. Furthermore, 41% patients underwent 26 reinterventions for PS. Patients undergoing PS-related reintervention had a significantly larger native pulmonary artery: aortic annulus size ratio than those not receiving reintervention (1.69 vs. 1.41, P = 0.02). This ratio was the only predictor of PS-related reintervention; it was significantly higher in the TBA group than in the TGA/VSD group. PS-related reintervention was required more in the TBA group than in the TGA/VSD group.
Conclusions: Regardless of complex coronary anatomy and associated anomalies, early and late survival were acceptable. Postoperative PS was strongly associated with having a larger native pulmonary valve, suggesting that an optimal surgical reconstruction was required for achieving an appropriate aortopulmonary anatomical relationship during ASO. (243 words
Mechanistic species distribution modeling reveals a niche shift during invasion
Niche shifts of nonnative plants can occur when they colonize novel climatic conditions. However, the mechanistic basis for niche shifts during invasion is poorly understood and has rarely been captured within species distribution models. We quantified the consequence of between-population variation in phenology for invasion of common ragweed (Ambrosia artemisiifolia L.) across Europe. Ragweed is of serious concern because of its harmful effects as a crop weed and because of its impact on public health as a major aeroallergen. We developed a forward mechanistic species distribution model based on responses of ragweed development rates to temperature and photoperiod. The model was parameterized and validated from the literature and by reanalyzing data from a reciprocal common garden experiment in which native and invasive populations were grown within and beyond the current invaded range. It could therefore accommodate between-population variation in the physiological requirements for flowering, and predict the potentially invaded ranges of individual populations. Northern-origin populations that were established outside the generally accepted climate envelope of the species had lower thermal requirements for bud development, suggesting local adaptation of phenology had occurred during the invasion. The model predicts that this will extend the potentially invaded range northward and increase the average suitability across Europe by 90% in the current climate and 20% in the future climate. Therefore, trait variation observed at the population scale can trigger a climatic niche shift at the biogeographic scale. For ragweed, earlier flowering phenology in established northern populations could allow the species to spread beyond its current invasive range, substantially increasing its risk to agriculture and public health. Mechanistic species distribution models offer the possibility to represent niche shifts by varying the traits and niche responses of individual populations. Ignoring such effects could substantially underestimate the extent and impact of invasions
Navigated Self-Assembly of a Pd<sub>2</sub>L<sub>4</sub> Cage by Modulation of an Energy Landscape under Kinetic Control
Two cases of multiple infarctions due to vertebral arterial occlusion associated with atlantoaxial subluxation caused by rheumatoid arthritis
Case 1: A 58-year-old woman with rheumatoid arthritis (RA) suffered from pontine and cerebellar infarctions and underwent three-dimensional computed tomography angiography (3D-CTA) of the vertebral artery (VA) with left-sided rotation of the head. This revealed a destroyed right atlantoaxial (AA) joint and right VA occlusion, which had caused the infarction. No recurrent infarctions have been observed after transarticular screw fixation (Magerl technique) was performed. Case 2: A 68-yearold woman with RA also suffered from pontine and cerebellar infarctions and underwent 3D-CTA of the VA with right-sided rotation of the head. This revealed a destroyed left AA joint and left VA occlusion, which had caused the infarction. No recurrentinfarctions have been observed after posterior fusion between the occiput and 3rd cervical vertebra was performed. In both cases of RA, who had multiple infarctions due to VA occlusion and a temporary thrombus formation, 3D-CTA in a rotated position helped to diagnose arterial occlusion. In addition, posterior fusion of the AA joint was a useful surgical technique
Indication for Endoscopic Resection of Submucosal Colorectal Carcinoma: Special Reference to Lymph Node Metastasis
We investigated the relationship between histological factors and lymph node metastasis in
77 lesions with submucosally invasive colorectal carcinomas to establish useful criteria for
lesions in which endoscopic treatment alone results in cure of malignancy. There were positive
correlations between histological factors, including the level of invasion, the histologic grade,
presence or absence of lymphatic invasion, presence or absence of budding, and lymph node
metastasis (p < 0.05, p < 0.05, p < 0.005, p < 0.01). The presence or absence of venous
invasion did not influence lymph node metastasis. Laparoscopic surgery involving lymph node
dissection should be indicated for sm1 carcinoma lesions with unfavorable histological factors.
In lesions diagnosed as sm2 or sm3 prior to resection, intestinal resection involving lymph node
dissection by laparoscopic surgery should be directly performed without endoscopic resection
Prehospital predicting factors using a decision tree model for patients with witnessed out-of-hospital cardiac arrest and an initial shockable rhythm
The effect of prehospital factors on favorable neurological outcomes remains unclear in patients with witnessed out-of-hospital cardiac arrest (OHCA) and a shockable rhythm. We developed a decision tree model for these patients by using prehospital factors. Using a nationwide OHCA registry database between 2005 and 2020, we retrospectively analyzed a cohort of 1,930,273 patients, of whom 86,495 with witnessed OHCA and an initial shockable rhythm were included. The primary endpoint was defined as favorable neurological survival (cerebral performance category score of 1 or 2 at 1 month). A decision tree model was developed from randomly selected 77,845 patients (development cohort) and validated in 8650 patients (validation cohort). In the development cohort, the presence of prehospital return of spontaneous circulation was the best predictor of favorable neurological survival, followed by the absence of adrenaline administration and age. The patients were categorized into 9 groups with probabilities of favorable neurological survival ranging from 5.7 to 70.8% (areas under the receiver operating characteristic curve of 0.851 and 0.844 in the development and validation cohorts, respectively). Our model is potentially helpful in stratifying the probability of favorable neurological survival in patients with witnessed OHCA and an initial shockable rhythm.Tateishi K., Saito Y., Yasufuku Y., et al. Prehospital predicting factors using a decision tree model for patients with witnessed out-of-hospital cardiac arrest and an initial shockable rhythm. Scientific Reports 13, 16180 (2023); https://doi.org/10.1038/s41598-023-43106-w
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