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1.
J Nutr Sci Vitaminol (Tokyo) ; 69(5): 326-339, 2023.
Article in English | MEDLINE | ID: mdl-37940573

ABSTRACT

We previously reported that black tea consumption for 12 wk reduced the risk of acute upper respiratory tract inflammation, and improved secretory capacity in individuals with low salivary SIgA levels (Tanaka Y et al. 2021. Jpn Pharmacol Ther 49: 273-288). These results suggested that habitual black tea consumption improves mucosal immunity. Therefore, in this study we evaluated the effect of black tea intake on gut microbiota, which is known to be involved in mucosal immunity, by analyzing the bacterial flora and the short-chain fatty acids (SCFAs) concentration of feces collected during the above clinical study. The clinical design was a randomized, single-blind, parallel-group, placebo-controlled study with 72 healthy Japanese adult males and females, who consumed three cups of black tea (Black Tea Polymerized Polyphenols 76.2 mg per day) or placebo per day for 12 wk. In all subjects intake of black tea significantly increased abundance of Prevotella and decreased fecal acetic acid concentration. Particularly in the subjects with low salivary SIgA levels, the change over time of total bacteria, Prevotella, and butyrate-producing bacteria, which are involved in normalizing immune function, were higher in the black tea group than in the placebo group. In subjects with low abundance of Flavonifractor plautii a butyrate-producing bacteria, black tea consumption significantly increased salivary SIgA concentration and the absolute number of Flavonifractor plautii. In conclusion, our results suggest that improvement of mucosal immunity via an increase in butyrate-producing bacteria in the gut may partly contribute to the suppressive effect of black tea consumption on acute upper respiratory tract inflammation observed in our previous report.


Subject(s)
Camellia sinensis , Gastrointestinal Microbiome , Adult , Male , Female , Humans , Tea , Single-Blind Method , Immunoglobulin A, Secretory , Inflammation , Butyrates
2.
PM R ; 2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37844015

ABSTRACT

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment for hematological malignancies. Several complications following allo-HSCT, such as graft-versus-host disease, infection, and malnutrition, often cause physical dysfunction, and the assessment of physical function and evaluation of muscle mass are incompletely performed. Use of ultrasound (US) allows muscle mass measurement in patients with poor general conditions. In allo-HSCT recipients, the correlation between physical function and muscle thickness, as measured by US, remains unclear. OBJECTIVE: To clarify whether muscle thickness measured by US correlated with physical function in allo-HSCT recipients. DESIGN: A single-center prospective cohort study. SETTING: Hospital. PATIENTS: Ninety-two patients underwent allo-HSCT at our hospital from April 2017 to March 2019. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): Biceps and quadriceps muscle thickness measured by US, grip strength, isometric muscle strength (elbow flexion and knee extension), and 6-minute walking test (6MWT) before allo-HSCT and on days 30, 90, 180, 1 year, and 2 years after allo-HSCT. The implementation rates of these assessments were also investigated. RESULTS: Correlations were observed between biceps thickness and elbow flexion muscle strength/grip strength before allo-HSCT, on days 30, 90, 180, 1 year, and 2 years after allo-HSCT (r = 0.71/0.74, 0.73/0.72, 0.70/0.79, 0.67/0.75, 0.72/0.75, and 0.85/0.79, respectively, all p < .001). At the same time points, quadriceps thickness moderately correlated with knee extensor strength (r = 0.49, 0.50, 0.45, 0.64, 0.61, and 0.58, all p < .001). However, biceps and quadriceps thicknesses did not correlate with the 6MWT. The percentages of patients measured with US and 6MWT were 93.4% and 82.4% (p = .01) on day 30 and 97.5% and 87.8% (p = .02) on day 90, respectively. CONCLUSIONS: US assessment may be a useful alternative method for estimating muscle strength in fragile allo-HSCT recipients, particularly when physical function assessment is difficult to quantify.

3.
J Nat Med ; 77(3): 604-609, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36854953

ABSTRACT

Food allergy is recognized as a global medical problem with increasing prevalence in recent years. Currently, the treatment of food allergy mainly involves avoidance of allergens and allergen-specific immunotherapy. Barring the spontaneous resolution of food allergy during the growth process, this disease is difficult to treat fundamentally. In recent years, the use of functional food ingredients derived from natural products has been attracting attention for their prophylactic use in food allergy. Theaflavins, i.e., black tea polyphenols, are potent antioxidants that have inhibitory effects on a variety of diseases. However, little is known about the preventive effect of theaflavins on food allergy. In this study, we designed a mouse model of food allergy and examined the effect of theaflavins using the severity of diarrhea, a symptom of food allergy, as an indicator. The administration of a black tea extract rich in theaflavins or theaflavin 1 (subgroup of theaflavins) to mice reduced the severity of diarrhea when compared with a normal diet. A reduction in malondialdehyde levels, a key marker of lipid peroxidation, was also observed. Overall, these data suggest that theaflavins may potentially inhibit food allergy by alleviating oxidative stress in the colon and can be a potential food material for prevention of food allergy.


Subject(s)
Food Hypersensitivity , Polyphenols , Mice , Animals , Polyphenols/pharmacology , Polyphenols/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Tea , Ovalbumin , Food Hypersensitivity/drug therapy
5.
J Alzheimers Dis ; 91(2): 673-681, 2023.
Article in English | MEDLINE | ID: mdl-36463447

ABSTRACT

BACKGROUND: The relationship between transesophageal echocardiography findings and cognitive function. OBJECTIVE: This study aimed to establish an association between transesophageal echocardiography findings and cognitive function in stroke survivors. METHODS: A single-center study was conducted between April 1, 2017 and March 31, 2022. All subjects that were included had a past history of ischemic stroke and were admitted after >21 days from onset. The participants underwent cognitive function tests including a Mini-Mental State Examination, Revised Hasegawa Dementia Scale, Frontal Assessment Battery, and transesophageal echocardiography. RESULTS: The results of 126 participants were analyzed. The cognitive function of participants with a spontaneous echo contrast (+) in the left atrium including appendage or of those with an aorta-arch plaque with a maximum thickness ≥4 mm significantly worse while neither the patent foramen ovale nor the branch extending plaque influenced cognitive function (The median cognitive scores of the spontaneous echo contrast (-) versus (+) were 26 versus 22, p < 0.01**, 26 versus 21, p < 0.001***, and 14 versus 11, p < 0.01**. Those of the aortic-arch plaque max thickness (<4 mm) versus (≥4 mm) were 26 versus 25, p < 0.05*, 27 versus 24, p < 0.05*, and 15 versus 13, p < 0.05*). CONCLUSION: Our findings show that spontaneous echo contrast in the left atrium and aortic-arch atheroma detected by transesophageal echocardiography, were negatively associated with cognitive function.


Subject(s)
Plaque, Atherosclerotic , Stroke , Humans , Echocardiography, Transesophageal/methods , Plaque, Atherosclerotic/complications , Plaque, Atherosclerotic/diagnostic imaging , Heart Atria/diagnostic imaging , Cognition
6.
Opt Lett ; 47(20): 5417-5420, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36240378

ABSTRACT

We have demonstrated a simple method for achieving broadband amplification and short-pulse generation in a polarizing maintained (PM) Yb fiber amplifier with the implementation of a narrow bandpass filter (NBF). By using an NBF with a spectral bandwidth of 3.3 nm at a wavelength of 1036 nm before the PM Yb amplifier, the spectral bandwidth was extended by self-phase modulation (SPM) in the PM YDF amplifier. The recompressed pulse duration of 125 fs obtained with the NBF was nearly three times shorter than that (350 fs) achieved without the NBF, and therefore the peak intensity of 0.35 MW with the NBF was over two times greater in comparison with that (0.16 MW) obtained without the NBF. We believe that this simple method is useful for developing an all-fiber laser system for high-power short pulse generation.

7.
Neurol Sci ; 43(12): 6855-6864, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36071265

ABSTRACT

BACKGROUND: It is important to gauge mortality in real time following an ischemic stroke. However, there is limited in-hospital and post-discharge clinical data that focuses on the real-time prognosis of acute ischemic strokes. PURPOSE: To comprehensively analyze ischemic stroke mortality during a hospital stay and 1 year after the onset of a stroke. MATERIALS AND METHODS: Initially, 1514 consecutive acute ischemic stroke patients were admitted to our facility within 7 days after the onset of a stroke. Of these, 1116 patients who were successfully surveyed 1 year after onset were finally analyzed. Baseline, physical, laboratory, and stroke clinical data were recorded and analyzed. RESULTS: The proportion of deaths within 1 year was 14.5%, 4.9% without discharge was and 9.6% after discharge within 1 year. Cardioembolic ischemic strokes were responsible for nearly 50% of the deaths within 1 year while the remaining deaths were due to non-cardioembolic ischemic strokes. After 1 year, survival rate in the hospital decreased significantly, depending on whether the stroke was recurrent or if there was bleeding without a stroke. CONCLUSIONS: Our study reveals the real-time survival data 1 year after the onset of a stroke, in-hospital and post-discharge mortality rates, and several issues associated with the treatment of acute ischemic strokes.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Humans , Aftercare , Risk Factors , Patient Discharge , Stroke/complications , Registries , Prognosis , Brain Ischemia/complications
8.
Front Nutr ; 9: 850103, 2022.
Article in English | MEDLINE | ID: mdl-35571922

ABSTRACT

Naringenin (NRG) is a plant-derived flavonoid. Due to its antioxidant, anti-inflammatory, and analgesic activities it is beneficial to human health and is often used as a functional food ingredient; however, it has poor water solubility and low in vivo bioavailability. Therefore, the efficacy of NRG can be improved by enhancing its water solubility to increase gastrointestinal absorption. Conventional methods for the formulation of NRG are very complex and use toxic organic solvents, making them impractical for the production of functional foods. The objective of this study was to develop a safe and effective NRG-based functional food material. Previously, we established a technology to prepare amorphous solid dispersions (SDs) from functional food ingredients with poor water solubility and used hot-melt extrusion technology that is comparatively simple and does not involve the use of organic solvents. In this study, we prepared NRG SD and evaluated them both physicochemically and biochemically. NRG SD had superior water solubility and gastrointestinal absorption relative to native NRG and showed higher analgesic efficacy in rats than crystalline NRG. NRG SD was administered to mice in a mixed diet for 28 days, and organ weights and hematological/clinical biochemical parameters were assessed. NRG SD did not demonstrate severe adverse effects. The results suggest that NRG SD is a safe and highly efficacious formulation that can be used as a functional food material in the future.

9.
Anesth Prog ; 69(1): 46-48, 2022 04 01.
Article in English | MEDLINE | ID: mdl-35377933

ABSTRACT

We report a case of severe bradycardia during general anesthesia due to reduced atrioventricular conduction capacity believed to have been caused by the trigeminocardiac reflex (TCR). A 46-year-old woman was scheduled for intraoral scar revision under general anesthesia. When the surgeon opened her mouth intraoperatively, the patient's blood pressure immediately increased, and she developed significant bradycardia and a transient Mobitz type II second-degree atrioventricular block. It was assumed that the mandibular division of the trigeminal nerve (V-3) was stimulated by the surgeon stretching the patient's mouth open while remifentanil simultaneously provided sympatholytic effects, resulting in activation of the TCR. The patient quickly responded well to atropine and had no additional complications.


Subject(s)
Atrioventricular Block , Bradycardia , Bradycardia/etiology , Female , Humans , Mandible , Middle Aged , Mouth , Trigeminal Nerve
10.
Sci Rep ; 12(1): 1538, 2022 01 27.
Article in English | MEDLINE | ID: mdl-35087177

ABSTRACT

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients frequently show physical dysfunction due to loss of muscle mass. This study aimed to clarify the reliability and validity of ultrasound in evaluating muscle mass and to analyze the patterns of change in muscle mass before and after allo-HSCT. We conducted a prospective observational study using data from 68 patients who had undergone their first allo-HSCT. We evaluated the thickness of the quadriceps, biceps, and suprahyoid muscle. Three individual evaluators underwent this examination for each muscle before transplantation and on days 30, 90, and 180 after allo-HSCT. Inter-rater reliability was calculated using the interclass correlation (ICC), and the level of correlation between muscle mass measured by ultrasound and psoas muscle mass assessed using computed tomography (CT) was assessed using Pearson correlation. ICC values ranged from 0.897 to 0.977 in the measurement. The correlation scores were 0.730, 0.546 and 0.579 between psoas muscle and the biceps, quadriceps, and suprahyoid muscle. The thickness of the biceps and quadriceps muscle were both significantly decreased after allo-HSCT from baseline. These results showed that the ultrasound technique was a reliable tool for evaluating muscle mass and detecting changes in muscle mass following allo-HSCT.


Subject(s)
Hematopoietic Stem Cell Transplantation
11.
Neurol Sci ; 43(2): 1079-1086, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34287724

ABSTRACT

BACKGROUND: Although the relationship between amyotrophic lateral sclerosis (ALS) and cervical spondylotic myelopathy (CSM) is important, data relating to CSM complications in ALS remain lacking. PURPOSE: We aimed to investigate and validate the spinal cord conditions of ALS patients. MATERIALS AND METHODS: We recruited all patients diagnosed with ALS, Parkinson's disease (PD), or chronic inflammatory demyelinating polyneuropathy (CIDP) who were admitted to our department from April 1, 2017, to March 31, 2020. We analyzed the cervical or thoracolumbar magnetic resonance imaging (MRI) scans of these 128 patients. Data relating to spondylosis, cord compression, spinal canal diameter, spinal cord diameter, and the closest distance between the cervical spinal canal and cord were validated using MRI. RESULTS: Of the 128 patients, 52 had ALS, 48 had PD, and 28 had CIDP. The proportions of both cervical spondylosis and cervical cord compression were highest in the ALS group compared with the other patient groups (p < 0.05). The proportion of cervical spondylosis in ALS patients reached 38.3%, and that of cervical cord compression reached 53.2%. The closest distance between the cervical spinal canal and cord was also significantly smaller in ALS patients compared with CIDP patients (p < 0.05). In contrast to the cervical cord findings, there were no significant differences in the thoracolumbar cord between ALS patients and the other patient groups. CONCLUSIONS: Of the three disease groups, the proportion of CSM was highest in ALS patients. Furthermore, cervical cord conditions were significantly more crowded in the ALS patients than in the other patient groups.


Subject(s)
Amyotrophic Lateral Sclerosis , Cervical Cord , Spinal Cord Compression , Spinal Cord Diseases , Spondylosis , Amyotrophic Lateral Sclerosis/complications , Amyotrophic Lateral Sclerosis/epidemiology , Cervical Cord/diagnostic imaging , Cervical Vertebrae/diagnostic imaging , Cohort Studies , Humans , Incidence , Magnetic Resonance Imaging , Spinal Cord , Spinal Cord Compression/diagnostic imaging , Spinal Cord Compression/epidemiology , Spinal Cord Compression/etiology , Spondylosis/complications , Spondylosis/diagnostic imaging , Spondylosis/epidemiology
12.
Neurol Sci ; 43(4): 2387-2396, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34748067

ABSTRACT

BACKGROUND AND PURPOSE: Multiple embolic sources are sometimes observed simultaneously in patients with embolic stroke. The present study investigated the effects of coexisting aortic arch atheroma ≥ 4 mm thick and atrial fibrillation (AF) on short-term stroke recurrence and functional outcome. METHODS: Transesophageal echocardiography (TEE) was performed in consecutive embolic stroke patients, and 395 patients were classified into 4 groups according to the presence of aortic arch atheroma ≥ 4 mm thick and AF: AF - /ARCH - group, AF + /ARCH - group, AF - /ARCH + group, and AF + /ARCH + group. In accordance with these 4 groups, we evaluated stroke recurrence and all-cause death for 3 months after stroke onset, and also evaluated the 3-month functional outcome using the modified Rankin scale (mRS). RESULTS: Among the 128 AF patients, 39.1% also had aortic arch atheroma ≥ 4 mm thick. Of the 395 enrolled cases, the AF + /ARCH + group showed the highest frequencies of stroke recurrence and all-cause death during 3 months after onset. On multivariate analysis, stroke recurrence or all-cause death during 3 months after onset was relatively more frequent in the AF + /ARCH + group than in the AF + /ARCH - group (OR, 2.34; 95% CI, 0.82-6.69; p = 0.11), but that was not statistically significant, and poor functional outcome (mRS score 3-6) at 3 months was significantly more frequent in the AF + /ARCH + group than in the AF + /ARCH - group (OR, 2.59; 95% CI, 1.08-6.24; p = 0.0339). CONCLUSIONS: Aortic arch atheroma concomitant with AF is not rare and appears associated with increased risks of stroke recurrence and poor functional outcome.


Subject(s)
Atrial Fibrillation , Plaque, Atherosclerotic , Stroke , Aorta, Thoracic/diagnostic imaging , Atrial Fibrillation/complications , Atrial Fibrillation/epidemiology , Echocardiography, Transesophageal/adverse effects , Humans , Plaque, Atherosclerotic/complications , Plaque, Atherosclerotic/diagnostic imaging , Risk Factors , Stroke/complications , Stroke/diagnostic imaging , Stroke/epidemiology
13.
J Alzheimers Dis ; 84(2): 787-796, 2021.
Article in English | MEDLINE | ID: mdl-34602471

ABSTRACT

BACKGROUND: Many issues persist in the today's Alzheimer's disease (AD) screening and the breakthrough method is desired. OBJECTIVE: We aim to validate the association between venous reflux and AD, and to develop a new method for AD screening. METHODS: We examined spontaneous echo contrast, area, diameter, retrograde velocity, and anterograde velocity of the bilateral cervical internal jugular vein (IJV) using carotid ultrasonography. RESULTS: A total of 112 patients participated in this study, with 26 diagnosed as AD. The proportion of both or either IJV spontaneous echo contrast (+) occupied 25 of total 26 AD patients, which showed 96.2%of sensitivity and 98.5%negative predictive value. The IJV velocities also showed significant correlation with AD diagnosis, although the IJV area or diameter did not. CONCLUSION: Our results indicate that the validation of the spontaneous echo contrast or velocities of the IJV are convenient AD diagnosis screening methods and that the venous reflux disturbance correlates with AD development.


Subject(s)
Alzheimer Disease/diagnosis , Cognition/physiology , Echocardiography , Jugular Veins/physiology , Mass Screening , Regional Blood Flow , Aged , Female , Humans , Male
14.
PLoS One ; 16(9): e0257247, 2021.
Article in English | MEDLINE | ID: mdl-34555048

ABSTRACT

Although a significant association between periodontal disease and atherosclerotic cardiovascular disease has been reported, their cause-to-effect relationship remains controversial. This randomized controlled clinical trial aimed to investigate the effect of advanced self-care on atherosclerotic cardiovascular disease-related vascular function markers flow-mediated brachial artery dilatation (FMD) and serum asymmetric dimethylarginine (ADMA) level in patients with early-stage periodontal disease. The study was designed as a parallel group, 3-month follow-up, open-label, randomized controlled trial. The control group received standard care for periodontal diseases, whereas the test group additionally applied disinfectant using a custom-fabricated prescription tray for advanced self-care twice a day. Overall, 110 patients provided data for FMD and serum ADMA level. No significant improvements in FMD were observed in the control (mean increase, -0.1%; 95% confidence interval [CI], -1.0-0.8; P = 0.805) or test (mean increase, -0.3%; 95% CI, -1.1-0.4; P = 0.398) group. No significant changes in serum ADMA levels were observed (mean reduction, 0.01 µmol/L; 95% CI, -0.00-0.02; P = 0.366 and mean reduction, 0.00 µmol/L; 95% CI, -0.01-0.01; P = 0.349, respectively). No significant between-group differences were found in FMD (mean difference, -0.2%; 95% CI, -1.4-0.9; p = 0.708) or serum ADMA levels (mean difference, 0.01 nmol/L; 95% CI, -0.00-0.03; p = 0.122). Significant improvements in the average probing pocket depth were observed in the control and test groups. The bleeding on probing score in the test group was significantly reduced, while that in the control group was reduced, although not significantly. Periodontal care for a 3-month duration did not provide better endothelial function although improvements of periodontal status in patients with early-stage periodontal diseases. This trial is registered in UMIN Clinical Trials Registry (www.umin.ac.jp/ctr/; ID: UMIN000023395).


Subject(s)
Atherosclerosis/prevention & control , Oral Hygiene/methods , Periodontal Diseases/prevention & control , Periodontal Diseases/therapy , Self Care , Adult , Aged , Arginine/analogs & derivatives , Arginine/blood , Atherosclerosis/complications , Biomarkers/blood , Brachial Artery/pathology , Dilatation, Pathologic , Endothelium, Vascular/drug effects , Female , Follow-Up Studies , Humans , Japan , Male , Mandible/physiology , Maxilla/physiology , Middle Aged , Treatment Outcome , Young Adult
16.
J Atheroscler Thromb ; 28(7): 776-785, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-32908035

ABSTRACT

AIM: Aortic arch atherosclerosis, particularly complex aortic arch plaques (CAPs), is an important source of cerebral emboli. CAPs and atrial fibrillation (AF) often co-exist; however, the prevalence and risk of CAPs in acute ischemic stroke patients with AF is unclear. METHODS: In patients with acute ischemic stroke with non-valvular AF admitted to Jichi Medical University Hospital during April 2016 to September 2019, we retrospectively evaluated the presence of CAPs on transesophageal echocardiography (TEE). RESULTS: CAPs were observed in 41 (38.7 %) of 106 patients with non-valvular AF. Older age, diabetes mellitus, chronic kidney disease, low high-density lipoprotein cholesterol (HDL-C) levels, higher levels of glycohemoglobin A1c (HbA1c), higher CHADS2 and CHA2DS2-VASc scores, and intracranial or carotid artery stenosis were more frequently observed in CAPs-positive than in CAPs-negative patients. In multivariable analyses, older age (odds ratio [OR]: 1.2 per year increase; 95% confidence interval [CI]: 1.07-1.24; P<0.0001), diabetes mellitus (OR: 4.7; 95%CI: 1.27-17.35; P<0.05), and low HDL-C (OR: 0.95 per 1 mg/dl increase; 95%CI: 0.92-0.99; P<0.01) were independent risk factors for CAPs. The prevalence of CAPs was age-dependent, and there was a significantly higher risk in patients aged either 75-84 years or >84 years than in those aged <65 (OR: 7.6; 95%CI: 1.50-38.62, and OR: 32.1; 95%CI: 5.14-200.11, respectively). CONCLUSIONS: Even in patients with ischemic stroke with non-valvular AF, concomitant CAPs should be considered in older individuals and those who have diabetes or low HDL-C.


Subject(s)
Aorta, Thoracic , Aortic Diseases , Atrial Fibrillation , Ischemic Stroke , Plaque, Atherosclerotic , Age Factors , Aged , Aged, 80 and over , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/pathology , Aortic Diseases/complications , Aortic Diseases/diagnosis , Aortic Diseases/physiopathology , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Echocardiography, Transesophageal/methods , Female , Humans , Intracranial Embolism/diagnosis , Intracranial Embolism/epidemiology , Intracranial Embolism/etiology , Ischemic Stroke/diagnosis , Ischemic Stroke/epidemiology , Ischemic Stroke/etiology , Japan/epidemiology , Male , Plaque, Atherosclerotic/complications , Plaque, Atherosclerotic/diagnostic imaging , Prevalence , Retrospective Studies , Risk Assessment/methods , Risk Assessment/statistics & numerical data , Risk Factors
17.
RSC Adv ; 11(33): 20570-20579, 2021 Jun 03.
Article in English | MEDLINE | ID: mdl-35479912

ABSTRACT

A series of Ru and Ni supported catalysts were prepared and their catalytic performance was evaluated in the steam reforming of xylenes. The effects of active metals, active metal loading sequence, and the calcination temperature of the support on the catalyst activity and stability were investigated. The bimetallic 2Ru → 15Ni catalyst shows much higher activity and stability than the monometallic 2Ru and 15Ni catalyst owing to the synergic effect of Ni and Ru. The 2Ru → 15Ni catalyst has the least coke deposition owing to its high conversion performance and much less coke precursor being formed on the catalyst surface. After decoking, most of the small-sized pores cannot be recovered because of the pore collapse under severe hydrothermal conditions. o-Xylene has the lowest reactivity due to electronic and steric effects. Besides the steam reforming reaction, demethylation and C-C cracking are also observed, forming benzene and toluene. The catalyst with a loading sequence of 15Ni → 2Ru shows high activity at low temperatures (550-600 °C), but undergoes an activity drop at high temperatures (625-650 °C) because the Ni sintering at high temperatures greatly affects the state of Ru on the catalyst. The catalyst with a loading sequence of 2Ru → 15Ni has an advantage at high temperatures owing to its better sintering resistance. The simultaneously loaded 2Ru ↔ 15Ni catalyst shows the lowest activity. The high calcination temperature of the support enhances the catalyst stability by eliminating the small-sized pores before reaction; on the other hand, the elimination of pores decreases the dispersion of the active metals. The 2Ru → 15Ni catalyst calcined at 1000 °C balances the active metal dispersion and resistance to sintering under severe hydrothermal conditions, showing the best activity and stability. The catalyst calcined at 1000 °C has the best coke resistance with only 0.166 g gcat -1 of coke formation after the 24 h durability test. The DTG results indicate that the carbon formed on the catalysts is mainly graphitic carbon.

18.
J Thromb Thrombolysis ; 51(2): 522-529, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32583305

ABSTRACT

The treatment of ischemic stroke has recently witnessed dramatic developments. However, there are limited data on ischemic stroke characteristics in aged patients. As part of the South Tochigi Acute Ischemic Stroke Registry, we prospectively enrolled 636 consecutive acute ischemic stroke patients (within 7 days after the onset) who were ≥ 60 years of age and who were admitted to two independent institutes from April 1, 2016 to February 28, 2019. We analyzed three groups divided by age: early-aged (60-69 years), middle-aged (70-79 years), and oldest-aged (≥ 80 years). From the 636 subjects, 194 were early-aged, 215 were middle-aged, and 227 were oldest-aged. There were significant differences in the ischemic stroke subtypes in each aging group (p < 0.01). The proportion of cardioembolism was 22.2% in early-aged, 27.4% in middle-aged, and 41.4% in the oldest-aged patients. The proportion of patients with a modified Rankin Scale of 0-2 at 1 year after onset decreased to 42.2% in middle-aged and 17.8% in oldest-aged with cardioembolic ischemic stroke. The proportion of patients receiving anticoagulation therapy before admission was 25.6% (36.7% of atrial fibrillation [AF]) in early-aged, 39.0% (52.3% of AF) in middle-aged, and 18.1% (21.0% of AF) in oldest-aged patients (p < 0.001). Our study reports characteristics of clinical ischemic stroke in an aging population. The assessment of cardiogenic embolism is important for an aging population.


Subject(s)
Embolic Stroke/etiology , Ischemic Stroke/etiology , Age Factors , Aged , Aged, 80 and over , Embolic Stroke/diagnosis , Female , Humans , Ischemic Stroke/diagnosis , Male , Middle Aged , Prospective Studies
19.
Sci Rep ; 10(1): 14460, 2020 Sep 02.
Article in English | MEDLINE | ID: mdl-32879406

ABSTRACT

A mode-locked laser that can produce a broadband spectrum and ultrashort pulse has been applied for many applications in an extensive range of scientific fields. To obtain stable mode-locking during a long time alignment-free, a semiconductor saturable absorber is one of the most suitable devices. Dynamics from noise to a stable mode-locking state in the spectral-domain are known as complex and a non-repetitive phenomenon with the time scale from nanoseconds to milliseconds. Thus, a conventional spectrometer, which is composed of a grating and line sensor, cannot capture the spectral behavior from noise to stable mode-locking. As a powerful spectral measurement technique, a time-stretch dispersive Fourier transformation (TS-DFT) has been recently used to enable a successive single-shot spectral measurement over a couple of milliseconds time span. Here, we experimentally demonstrate real-time spectral evolution of femtosecond pulse build-up in a homemade passive mode-locked Yb fiber laser with a semiconductor saturable absorber mirror using TS-DFT. Capturing 700 consecutive spectra (~ 17 µs time window) in real-time using the time-stretch technique, we are able to resolve the transient dynamics that lead to stable mode-locking. Before setting stable mode-locking, an oscillating or shifting fringe pattern in the consecutive spectra was detected. This signature proves the existence of multiple pulses (including a soliton molecule) which is temporally separated with a different relative phase. The dynamics on multiple pulses is originated from a fast relaxation time of the saturable absorption effect. This study provides novel insights into understanding the pulse behavior during the birth of an ultrafast mode-locked laser pulse and the stable single-pulse operation which is highly stabilized.

20.
J Neurol Sci ; 415: 116924, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-32460146

ABSTRACT

OBJECTIVES: Magnetic resonance angiography (MRA), three-dimensional computed tomography angiography, and cerebral angiography may be used to assess intracranial vertebrobasilar stenosis. However, these examinations cannot be performed at patients' bedsides. Our purpose was to develop a new bedside method to assess intracranial vertebrobasilar arterial stenosis. METHODS: We developed the new method using carotid duplex ultrasonography combined with the head-up test. A total of 141 subjects admitted between June 1, 2017 and March 31, 2019 were enrolled in this study. We calculated vertebral arterial peak systolic velocities (PSVs), end-diastolic velocities (EDVs), and mean velocities (MVs) at 0°, 16°, and 30° head-up angles. Vertebrobasilar arterial stenosis was confirmed using MRA. RESULTS: We excluded 28 subjects and included data for 113 subjects and 226 vessels in the final analysis. Cervical vertebral arterial PSV, EDV, and MV gradually decreased from 0° to 30° only in stenotic intracranial vertebral arteries. Sensitivity (probability of detection) was 75.5% and specificity (true negative rate) was 79.7% when EDV at the 30° head-up angle decreased ≥19.5% from the initial 0° head-up angle. Specificity was better (86.4%; sensitivity: 69.4%) when EDV was <9.1 cm/s at the 30° head-up angle. CONCLUSION: This new method easily detects intracranial vertebrobasilar arterial stenosis.


Subject(s)
Carotid Stenosis , Ultrasonography, Doppler, Duplex , Blood Flow Velocity , Carotid Arteries/diagnostic imaging , Carotid Artery, Internal/diagnostic imaging , Constriction, Pathologic , Humans , Predictive Value of Tests , Sensitivity and Specificity
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