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排序方式: 共有781条查询结果,搜索用时 250 毫秒
21.
Nguyen Trung Dung Tran Viet Thu To Van Nguyen Bui Minh Thuy Masahito Hatsukano Koichi Higashimine Shinya Maenosono Ziyi Zhong 《RSC advances》2020,10(7):3775
In this work, we report the facile hydrothermal synthesis of manganese cobaltite nanoparticles (MnCo2O4.5 NPs) which can efficiently activate peroxymonosulfate (PMS) for the generation of sulfate free radicals (SO4˙−) and degradation of organic dyes. The synthesized MnCo2O4.5 NPs have a polyhedral morphology with cubic spinel structure, homogeneously distributed Mn, Co, and O elements, and an average size less than 50 nm. As demonstrated, MnCo2O4.5 NPs showed the highest catalytic activity among all tested catalysts (MnO2, CoO) and outperformed other spinel-based catalysts for Methylene Blue (MB) degradation. The MB degradation efficiency reached 100% after 25 min of reaction under initial conditions of 500 mg L−1 Oxone, 20 mg L−1 MnCo2O4.5, 20 mg L−1 MB, unadjusted pH, and T = 25 °C. MnCo2O4.5 NPs showed a great catalytic activity in a wide pH range (3.5–11), catalyst dose (10–60 mg L−1), Oxone concentration (300–1500 mg L−1), MB concentration (5–40 mg L−1), and temperature (25–55 °C). HCO3−, CO32− and particularly Cl− coexisting anions were found to inhibit the catalytic activity of MnCo2O4.5 NPs. Radical quenching experiments revealed that sulfate radicals are primarily responsible for MB degradation. A reaction sequence for the catalytic activation of PMS was proposed. The as-prepared MnCo2O4.5 NPs could be reused for at least three consecutive cycles with small deterioration in their performance due to low metal leaching. This study suggests a facile route for synthesizing MnCo2O4.5 NPs with high catalytic activity for PMS activation and efficient degradation of organic dyes.Catalytic degradation of organic dyes via manganese cobaltite nanoparticles-activated peroxymonosulfate. 相似文献
22.
Nghiem Nguyet Thu Truong Tuyet Mai Tran Th໋ Thu Trang Nguyen Anh Tuan Tran Chau Quyen Nguyen Lien Hanh Nguyen Huu Hoan Bui Thi Huong Lan Phung Thi Hau Ha Huy Tue Truong Viet Dung Ryohei Tsuji Yuta Watanabe Naoki Yamamoto Osamu Kanauchi 《Nutrients》2022,14(3)
Lactococcus lactis strain Plasma (LC-Plasma) is reported to have anti-viral effects via direct activation of plasmacytoid dendritic cells, which upregulate the production of type I and III interferons. A randomized, placebo-controlled, double-blind, parallel group study was designed for elementary schoolchildren, grades 1 to 3, in Vietnam. LC-Plasma or a control were administered to schoolchildren as a beverage (1.0 × 1011 count LC-Plasma/day/person). The primary endpoint was to determine the efficacy of LC-Plasma in reducing the cumulative days absent from school due to upper respiratory disease (URID) and gastrointestinal disease (GID), and the secondary endpoint was to evaluate the potency of LC-Plasma on URID/GID symptoms and general well-being scores. LC-Plasma intake significantly reduced the cumulative days absent from school due to URID/GID (Odds ratio (OR) = 0.57, p = 0.004) and URID alone (OR = 0.56, p = 0.005); LC-Plasma also significantly reduced the number of cumulative fever positive days during the first 4 weeks of intervention (OR = 0.58, p = 0.001) and cumulative days with diarrhea during the last 4 weeks of the intervention period (OR = 0.78, p = 0.01). The number of positive general wellbeing days was significantly improved in the LC-Plasma group compared with the control throughout the intervention period (OR = 0.93, 0.93, p = 0.03, 0.04 in the first and last 4 weeks of the intervention, respectively). These data suggest that LC-Plasma seems to improve the health condition of elementary schoolchildren and reduces school absenteeism due to infectious disease, especially URID. 相似文献
23.
In this study, Mn2O3/MIL-100(Fe) composite was successfully synthesized by the hydrothermal method and applied for photocatalytic removal of rhodamine B (RhB) in water. The physical and chemical properties of the synthesized materials were characterized by XRD, FTIR, SEM, UV-visible, and BET analyses. Experimental results showed a great enhancement in the photocatalytic ability of the Mn2O3/MIL-100(Fe) composite as compared to individual Mn2O3 or MIL-100(Fe) under visible light and persulfate activation. The affecting factors such as pH, photocatalyst dose, RhB concentration, and Na2S2O8 concentration were investigated to find out the best conditions for efficient photocatalysis. By conducting a radical quenching test, all radicals of HO˙, SO4˙−, 1O2, and O2˙− were found to be important in photocatalytic decomposition. The mechanism was proposed for the enhancement of photocatalytic RhB removal via band potential calculation, charge separation, surface redox reaction, and key reactive oxidation species. With its durability, reusability, and high efficiency, the Mn2O3/MIL-100(Fe) composite emerges as a potential photocatalyst working under visible light for application in wastewater treatment.Effective charge transfer enhances the persulfate activation of Mn2O3/MIL-100(Fe) for photocatalytic removal of RhB under LED-generated visible light. 相似文献
24.
Tessa Timmers Rik Ossenkoppele Denise Visser Hayel Tuncel Emma E Wolters Sander CJ Verfaillie Wiesje M van der Flier Ronald Boellaard Sandeep SV Golla Bart NM van Berckel 《Journal of cerebral blood flow and metabolism》2020,40(12):2464
The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods. 相似文献
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Neuregulin‐1 positively modulates glial response and improves neurological recovery following traumatic spinal cord injury
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Arsalan Alizadeh Scott M. Dyck Hardeep Kataria Ghazaleh M. Shahriary Dung H. Nguyen Kallivalappil T. Santhosh Soheila Karimi‐Abdolrezaee 《Glia》2017,65(7):1152-1175
Spinal cord injury (SCI) results in glial activation and neuroinflammation, which play pivotal roles in the secondary injury mechanisms with both pro‐ and antiregeneration effects. Presently, little is known about the endogenous molecular mechanisms that regulate glial functions in the injured spinal cord. We previously reported that the expression of neuregulin‐1 (Nrg‐1) is acutely and chronically declined following traumatic SCI. Here, we investigated the potential ramifications of Nrg‐1 dysregulation on glial and immune cell reactivity following SCI. Using complementary in vitro approaches and a clinically‐relevant model of severe compressive SCI in rats, we demonstrate that immediate delivery of Nrg‐1 (500 ng/day) after injury enhances a neuroprotective phenotype in inflammatory cells associated with increased interleukin‐10 and arginase‐1 expression. We also found a decrease in proinflammatory factors including IL‐1β, TNF‐α, matrix metalloproteinases (MMP‐2 and 9) and nitric oxide after injury. In addition, Nrg‐1 modulates astrogliosis and scar formation by reducing inhibitory chondroitin sulfate proteoglycans after SCI. Mechanistically, Nrg‐1 effects on activated glia are mediated through ErbB2 tyrosine phosphorylation in an ErbB2/3 heterodimer complex. Furthermore, Nrg‐1 exerts its effects through downregulation of MyD88, a downstream adaptor of Toll‐like receptors, and increased phosphorylation of Erk1/2 and STAT3. Nrg‐1 treatment with the therapeutic dosage of 1.5 μg/day significantly improves tissue preservation and functional recovery following SCI. Our findings for the first time provide novel insights into the role and mechanisms of Nrg‐1 in acute SCI and suggest a positive immunomodulatory role for Nrg‐1 that can harness the beneficial properties of activated glia and inflammatory cells in recovery following SCI. 相似文献
29.
Background Little published evidence supports the widely held contention that research in pregnancy is underfunded compared with other disease areas.
Objectives To assess absolute and relative government and charitable funding for maternal and perinatal research in the UK and internationally.
Search strategy, selection criteria, data collection, and analysis Major research funding bodies and alliances were identified from an Internet search and discussions with opinion leaders/senior investigators. Websites and annual reports were reviewed for details of strategy, research spend, grants awarded, and allocation to maternal and/or perinatal disease using generic and disease-specific search terms.
Main results Within the imprecision in the data sets, ≤1% of health research spend in the UK was on maternal/perinatal health. Other countries fared better with 1–4% investment, although nonexclusive categorisation may render this an overestimate. In low-resource settings, government funders focused on infectious disease but not maternal and perinatal health despite high relative disease burden, while global philanthropy concentrated on service provision rather than research. Although research expenditure has been deemed as appropriate for 'reproductive health' disease burden in the UK, there are no data on the equity of maternal/perinatal research spend against disease burden, which globally may justify a manyfold increase.
Author's conclusions This systematic review of research expenditure and priorities from national and international funding bodies suggests relative underinvestment in maternal/perinatal health. Contributing factors include the low political priority given to women's health, the challenging nature of clinical research in pregnancy, and research capacity dearth as a consequence of chronic underinvestment. 相似文献
Objectives To assess absolute and relative government and charitable funding for maternal and perinatal research in the UK and internationally.
Search strategy, selection criteria, data collection, and analysis Major research funding bodies and alliances were identified from an Internet search and discussions with opinion leaders/senior investigators. Websites and annual reports were reviewed for details of strategy, research spend, grants awarded, and allocation to maternal and/or perinatal disease using generic and disease-specific search terms.
Main results Within the imprecision in the data sets, ≤1% of health research spend in the UK was on maternal/perinatal health. Other countries fared better with 1–4% investment, although nonexclusive categorisation may render this an overestimate. In low-resource settings, government funders focused on infectious disease but not maternal and perinatal health despite high relative disease burden, while global philanthropy concentrated on service provision rather than research. Although research expenditure has been deemed as appropriate for 'reproductive health' disease burden in the UK, there are no data on the equity of maternal/perinatal research spend against disease burden, which globally may justify a manyfold increase.
Author's conclusions This systematic review of research expenditure and priorities from national and international funding bodies suggests relative underinvestment in maternal/perinatal health. Contributing factors include the low political priority given to women's health, the challenging nature of clinical research in pregnancy, and research capacity dearth as a consequence of chronic underinvestment. 相似文献
30.
Lan Huu NGUYEN Dung Huy NGUYEN Thach Ngoc TRAN Phung Tran NGUYEN Quy Hoang THI Yossef AELONY Jean Paul Daniel HOMASSON 《Respirology (Carlton, Vic.)》2010,15(3):491-494
Background and objective: A high percentage of bronchoscopically extracted foreign bodies in Ho Chi Minh City were pits of the sapote fruit, a finding previously unreported. This paper presents a review of foreign body extractions, which identifies the substances found, documents the diagnostic pathway and draws attention to the specific aspiration risk of the sapote pit. Methods: The records of 100 consecutive adults who were found to have a bronchial foreign body during flexible bronchoscopy were reviewed. Results: In 83% of patients, the foreign body extraction was performed more than 2 weeks after the aspiration had occurred. In only 34% of patients was the diagnosis of an aspirated foreign body considered early in the patient's clinical course. The most frequent foreign bodies found were sapote pits (41%), followed by small bones (38%). Foreign bodies were lodged more frequently in the right bronchial tree (64%). In 98% of patients, the foreign bodies were successfully removed with the flexible scope. There was one postoperative death, which was not ascribed to the procedure. Conclusions: Physicians need to consider foreign body aspirations when evaluating patients with recurrent pneumonia, unexplained cough or atelectasis. Awareness of this problem might lead to public health measures that could reduce the incidence of these aspirations. 相似文献