Solvent Extraction of DNA with a Hydrolysable Double-chain Surfactant

A cationic lipophilic surfactant with two hydrolysable groups, di(1-octadecyloxycarbonylmethyl)dimethylammonium chloride, was synthesized and solvent extraction of deoxyribonucleotide (DNA) into organic solution (isooctane/1-octanol) with it as an extractant was examined. Not only a forward extraction of DNA into the organic phase but also back extraction into the aqueous phase (pH9) at room temperature proceeded efficiently. The forward extraction is promoted by electrostatic interactions of the surfactant and DNA and the back extraction is exclusively caused by hydrolysis of the surfactant to a non-surfactant.ArticleSEPARATION SCIENCE AND TECHNOLOGY. 44(2):466-475 (2009)journal articl

Ordered Counterfactual Explanation by Mixed-Integer Linear Optimization

Post-hoc explanation methods for machine learning models have been widely used to support decision-making. One of the popular methods is Counterfactual Explanation (CE), also known as Actionable Recourse, which provides a user with a perturbation vector of features that alters the prediction result. Given a perturbation vector, a user can interpret it as an "action" for obtaining one's desired decision result. In practice, however, showing only a perturbation vector is often insufficient for users to execute the action. The reason is that if there is an asymmetric interaction among features, such as causality, the total cost of the action is expected to depend on the order of changing features. Therefore, practical CE methods are required to provide an appropriate order of changing features in addition to a perturbation vector. For this purpose, we propose a new framework called Ordered Counterfactual Explanation (OrdCE). We introduce a new objective function that evaluates a pair of an action and an order based on feature interaction. To extract an optimal pair, we propose a mixed-integer linear optimization approach with our objective function. Numerical experiments on real datasets demonstrated the effectiveness of our OrdCE in comparison with unordered CE methods.Comment: 20 pages, 5 figures, to appear in the 35th AAAI Conference on Artificial Intelligence (AAAI 2021

Clinical training stress and autonomic nervous function in female medical technology students : analysis of heart rate variability and 1/f fluctuation

To evaluate the level of stress induced by clinical training, ambulatory electrocardiograms from 12 healthy female medical technology students were recorded and the spectral components of heart rate variability (HRV) were analyzed as an index of autonomic nervous function. The HF power reflecting parasympathetic tone was significantly decreased at awakening, compared with that before clinical training (p 0.01). The LF/HF ratio reflecting sympathetic activity also significantly increased during, compared with before clinical training (p 0.01). The slope of the spectral density also changed before and during the clinical training from -1.20 0.04 to -1.09 0.03 (p 0.05). The 1/f fluctuation of HRV appeared comfortable, and tension was apparently adequate while undergoing clinical training. None of these HRV indices statistically changed while asleep. Thus, the students perceived the stress as a comfortable level of tension and analyzing spectral components and 1/f fluctuation of HRV might be a useful method for evaluating study stress

Antral Somatostatin Contents and Acidity of Gastric Juice in Normal Subjects and Patients with Duodenal Ulcer

The antral somatostatin contents were investigated in biopsy specimens of the antrum from normal subjects and patients with duodenal ulcer. There was good correlation (r=0.77044) between antral somatostatin contents and maximal acidity in normal subjects, but the correlation between antral somatostatin contents and maximal acid output was not significant (r=0.254367). This result may indicate that antral somatostatin content is regulated by intragastric pH in normal subjects. On the other hands, no correlation was observed between antral somatostatin contents and acidity or acid output in patients with duodenal ulcer. Therefore the impaired regulation of acid on antral somatostatin contents could be one of the important factors in the pathogenesis of duodenal ulcer disease

Multidendritic sensory neurons in the adult Drosophila abdomen: origins, dendritic morphology, and segment- and age-dependent programmed cell death

<p>Abstract</p> <p>Background</p> <p>For the establishment of functional neural circuits that support a wide range of animal behaviors, initial circuits formed in early development have to be reorganized. One way to achieve this is local remodeling of the circuitry hardwiring. To genetically investigate the underlying mechanisms of this remodeling, one model system employs a major group of <it>Drosophila </it>multidendritic sensory neurons - the dendritic arborization (da) neurons - which exhibit dramatic dendritic pruning and subsequent growth during metamorphosis. The 15 da neurons are identified in each larval abdominal hemisegment and are classified into four categories - classes I to IV - in order of increasing size of their receptive fields and/or arbor complexity at the mature larval stage. Our knowledge regarding the anatomy and developmental basis of adult da neurons is still fragmentary.</p> <p>Results</p> <p>We identified multidendritic neurons in the adult <it>Drosophila </it>abdomen, visualized the dendritic arbors of the individual neurons, and traced the origins of those cells back to the larval stage. There were six da neurons in abdominal hemisegment 3 or 4 (A3/4) of the pharate adult and the adult just after eclosion, five of which were persistent larval da neurons. We quantitatively analyzed dendritic arbors of three of the six adult neurons and examined expression in the pharate adult of key transcription factors that result in the larval class-selective dendritic morphologies. The 'baseline design' of A3/4 in the adult was further modified in a segment-dependent and age-dependent manner. One of our notable findings is that a larval class I neuron, ddaE, completed dendritic remodeling in A2 to A4 and then underwent caspase-dependent cell death within 1 week after eclosion, while homologous neurons in A5 and in more posterior segments degenerated at pupal stages. Another finding is that the dendritic arbor of a class IV neuron, v'ada, was immediately reshaped during post-eclosion growth. It exhibited prominent radial-to-lattice transformation in 1-day-old adults, and the resultant lattice-shaped arbor persisted throughout adult life.</p> <p>Conclusion</p> <p>Our study provides the basis on which we can investigate the genetic programs controlling dendritic remodeling and programmed cell death of adult neurons, and the life-long maintenance of dendritic arbors.</p

IgA 腎症における腎生検後 5 年間の治療反応性と腎予後の関連性

Background: Immunoglobulin A nephropathy (IgAN) is the most common type of primary glomerulonephritis. Since most patients have a relatively benign renal prognosis, long-term follow-up is required. During such a long course of disease, relapse of IgAN is occasionally observed after upper respiratory tract infection or without any trigger. However, little is known about the impact of relapse on long-term renal outcomes. Methods: In this retrospective cohort study of biopsy-proven primary IgAN, we analyzed the association of 5-year therapeutic responsiveness (relapse) with the subsequent development of end-stage kidney disease (ESKD) using a 5-year landmark analysis (Cox model) and explored predictors of relapse from histological and clinical data at baseline. Results: Among 563 patients from the exploratory cohort, most relapses (13.7%) occurred within 5 years after treatment. Using 5-year landmark analysis, among 470 patients, 79 developed ESKD during a median follow-up period of 155 months. Even after adjustment for clinicopathological relevant confounders, hazard ratios (95% confidence intervals) in the relapse and non-responder groups compared with the remission group were 2.86 (1.41-5.79) and 2.74 (1.48-5.11), respectively. Among 250 patients who achieved remission within 5 years, proteinuria, eGFR, mesangial hypercellularity, endocapillary hypercellularity, segmental sclerosis, and crescent, but not interstitial fibrosis/tubular atrophy, were independent predictors of 5-year relapse in multivariable logistic regression analysis, CONCLUSIONS: Both relapsers and non-responders had similarly strong association with ESKD in patients with IgAN. We also confirmed the predictors of relapse 5 years after renal biopsy, which may guide the treatment strategies for patients with IgAN who occasionally relapse after remission.博士（医学）・乙第1530号・令和5年3月15

Diagnostic utility of fractional exhaled nitric oxide in prolonged and chronic cough according to atopic status

AbstractBackgroundCough-variant asthma (CVA) and cough-predominant asthma (CPA) are the major causes of persistent cough in Japan. The utility of fractional exhaled nitric oxide (FeNO) measurement in the differential diagnosis of persistent cough has been reported, but the influence of atopic status, which is associated with higher FeNO levels, on the diagnostic utility of FeNO has been unknown.MethodsWe retrospectively analyzed 105 non-smoking patients with prolonged and chronic cough that were not treated with corticosteroids and anti-leukotrienes.ResultsCPA was diagnosed in 37 patients, CVA in 40, and non-asthmatic cough (NAC) in 28. FeNO levels were significantly higher in the CPA [35.8 (7.0–317.9) ppb] and CVA [24.9 (3.1–156.0) ppb] groups than in the NAC group [18.2 (6.9–49.0) ppb] (p < 0.01 by Kruskal–Wallis test). The optimal cut-off for distinguishing asthmatic cough (AC; CPA and CVA) from NAC was 29.2 ppb [area under the curve (AUC) 0.74, p < 0.01]. Ninety-one percent of subjects with FeNO levels ≥29.2 ppb had AC. Meanwhile, 40% of AC patients had FeNO levels <29.2 ppb. Stratified cut-off levels were 31.1 ppb (AUC 0.83) in atopic subjects vs. 19.9 ppb (AUC 0.65) in non-atopic subjects (p = 0.03 for AUC).ConclusionsAlthough high FeNO levels suggested the existence of AC, lower FeNO levels had limited diagnostic significance. Atopic status affects the utility of FeNO levels in the differential diagnosis of prolonged and chronic cough

胎盤増殖因子の可溶性Fms様チロシンキナーゼ-1に対する血中濃度比の上昇は安定冠動脈疾患患者における有害事象発症の予測因子である

OBJECTIVE: To investigate the predictive values of placental growth factor (PlGF) and its endogenous antagonist, soluble fms-like tyrosine kinase-1 (sFlt-1), for the long-term prognosis of patients with stable coronary artery disease (CAD). Both PlGF and sFlt-1 play important roles in the pathological mechanisms of atherosclerosis. We recently demonstrated that the plasma levels of these molecules are correlated with the severity of coronary atherosclerosis. METHODS: We enrolled 464 patients with stable CAD who consecutively underwent coronary angiography. Baseline blood samples were collected from the femoral artery immediately before coronary angiography (after the administration of 20 units of heparin), and the plasma levels of PlGF and sFlt-1 were measured. A Cox proportional hazard regression analysis was performed to evaluate the relationship between these parameters and the occurrence of all-cause death (ACD) and total cardiovascular events (TCVE) during a median follow-up of 3.3 years. RESULTS: A total of 31 ACDs and 51 TCVEs occurred. Patients with higher PlGF/sFlt-1 ratios (>4.22×10(-2)) had a significantly higher risk of both ACD and TCVE than patients with lower ratios (<4.22×10(-2)) (hazard ratio [HR]: 3.32, 95% confidence interval [CI]: 1.43 to 7.72, p=0.005, and HR: 2.23, 95% CI: 1.23 to 4.03, p=0.008, respectively). A multivariate analysis showed the PlGF/sFlt-1 ratio to be an independent predictor for ACD, but not TCVE.博士（医学）・甲615号・平成26年3月17日発行元の規定により、本文の登録不可。本文は以下のURLを参照 "http://dx.doi.org/10.2169/internalmedicine.52.9073