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1.
Neural Regen Res ; 17(3): 608-617, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34380901

RESUMO

Glial cells play an important role in signal transduction, energy metabolism, extracellular ion homeostasis and neuroprotection of the central nervous system. However, few studies have explained the potential effects of exosomes from glial cells on central nervous system health and disease. In this study, the genes expressed in exosomes from astrocytes and microglia were identified by deep RNA sequencing. Kyoto Encyclopedia of Genes and Genomes analysis indicated that several pathways in these exosomes are responsible for promoting neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease and Huntington's disease. Gene ontology analysis showed that extracellular exosome, mitochondrion and growth factor activity were enriched in exosomes from the unique astrocyte group, while extracellular exosome and mitochondrion were enriched in exosomes from the unique microglia group. Next, combined with the screening of hub genes, the protein-protein interaction network analysis showed that exosomes from astrocytes influence neurodegenerative diseases through metabolic balance and ubiquitin-dependent protein balance, whereas exosomes from microglia influence neurodegenerative diseases through immune inflammation and oxidative stress. Although there were differences in RNA expression between exosomes from astrocytes and microglia, the groups were related by the hub genes, ubiquitin B and heat shock protein family A (Hsp70) member 8. Ubiquitin B appeared to be involved in pleiotropic regulatory functions, including immune regulation, inflammation inhibition, protein catabolism, intracellular protein transport, exosomes and oxidative stress. The results revealed the clinical significance of exosomes from glia in neurodegenerative diseases. This study was approved by the Animal Ethics Committee of Nantong University, China (approval No. S20180102-152) on January 2, 2018.

2.
Appl Opt ; 60(21): 6030-6043, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34613267

RESUMO

White light interferometry is a well-established surface recovery technique. In this paper, a white light signal processing algorithm based on phase error compensation using spectrum selection is proposed. The derived nonlinear phase distribution from the correlogram is modeled as the combination of random errors and systemic deviations. By developing a new, to the best of our knowledge, recovery algorithm, the phase noise can be separated from the linear map and significantly attenuated. Based on the proposed algorithm, the spectrum features of white light LEDs and halogen lamps are investigated in detail. The inner products defined by three selected points are employed to generate a coefficient to evaluate the linearity of an unwrapped phase map within a certain spectrum region. The optimal spectrum range corresponding to the best measurement performance can then be located where the coefficient approximates 1 and the spectrum energy stays relatively high. The simulations are carried out under different levels of SNR and scan step noises, which show that the new method can effectively reduce additional disturbance from the recovered topography. In experiments, the system with the proposed method is first calibrated by a step height standard (VLSI, 182.7±2.0nm) with the repeatability of 0.44 nm. A silicon wafer and three roughness standards are also tested to further verify the robustness of the new method.

3.
Small ; 17(46): e2103125, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34612010

RESUMO

Stimuli-responsive crystals capable of energy conversion have emerged as promising materials for smart sensors, actuators, wearable devices, and robotics. Here, a novel ferrocene-based organic molecule crystal (Fc-Cz) that possesses anisotropic piezoelectric, optical, and mechanical properties is reported. It is demonstrated that the new crystal Fc-Cz can be used as an ultrasensitive piezoelectric material in fabricating strain sensors. The flexible sensor made of crystal Fc-Cz can detect small strains/deformations and motions with a fast response speed. Analysis based on density functional theory (DFT) indicates that an external pressure can affect the dipole moment by changing the molecular configuration of the asymmetric single crystal Fc-Cz in the crystalline state, leading to a change of polarity, and thereby an enhanced dielectric constant. This work demonstrates a new artificial organic small molecule for high-performance tactile sensors, indicating its great potential for developing low-cost flexible wearable sensors.

4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(4): 513-520, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34494520

RESUMO

Objective To understand the current situation and predict the trends in number and composition of prenatal ultrasound screening staff in Beijing. Methods We analyzed the region,age,professional title and other characteristics of prenatal ultrasound screening personnel in Beijing during 2007-2015.We then built an ARIMA model basing on the current situation to predict the number and composition of the staff in 2016-2020. Results The number of prenatal ultrasound screening staff showed an upward trend in 2007-2020 and was predicted to reach 1269 in 2020.During this period,the educational achievement and professional title of the staff showed a downward trend,and the working years became shorter,mainly below 5 years.The proportion of resident doctors remained at 26.6%,and that of the staff receiving further education would reach 43.2% by the end of 2020. Conclusion The prediction under ARIMA model suggests that efforts should be made to strengthen the training of young doctors and provide them opportunities for further study.


Assuntos
Modelos Estatísticos , Diagnóstico Pré-Natal , Pequim , Feminino , Humanos , Gravidez , Ultrassonografia , Ultrassonografia Pré-Natal
5.
Lancet Reg Health West Pac ; 15: 100232, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34528013

RESUMO

Background: Ambient air pollution is leading risk factor for health burden in China. Few studies in China have investigated the economic loss related to short-term exposure to ambient PM2.5, which could trigger acute onset of cardiorespiratory diseases within a few days. Methods: Daily ambient air pollutants data are obtained for each city from the National Air Quality Monitoring System and daily hospitalization data are obtained from the urban employee-based basic medical insurance scheme database in 74 Chinese cities with an average coverage of 88.5 million urban employees during 2016-2017. A three-stage time-series analytic approach is used in this study to investigate the impact of short-term exposure to ambient fine particulate (PM2.5) air pollution on hospital admissions, expenses and hospital stays of three cause-specific cardiorespiratory diseases, including lower respiratory infections (LRI), coronary heart disease (CHD) and stroke in the included cities. Findings: Based on the time-series analysis using daily hospitalization data, 28,560 LRI cases, 54,600 CHD cases, and 23,989 stroke cases are attributable to ambient PM2.5 in the 74 cities during the study period, and the related attributable expenses are 220 million CNY (US$ 32.9 million) for LRI, 458 million CNY (US$ 68.5 million) for CHD, and 410 million CNY (US$ 65.8 million) for stroke, respectively. These attributable numbers account for 1.45% to 2.05% of total hospital admissions and 1.10% to 1.51% of total expenses for the three diseases during 2016-2017, respectively. The attributable numbers for the three cause-specific cardiorespiratory diseases would increase to 362,007 hospital admission cases and 3.68 billion CNY expenses ($US550 million) in the entire urban employee population (299 million) in China during 2016-2017, and the related direct economic loss of absence from work would be 798 million CNY (US$ 119.3 million). Interpretation: Our results support that short-term exposure to ambient PM2.5 pollution could lead to significant health and economic impacts in China. Reducing levels of ambient PM2.5 can avoid substantial health damage and expenditures, and generate appreciable economic benefits from decreasing absence from work. Funding: Natural Science Foundation of China (82073509, 71903010, 71903011), and the National Key Research and Development Program of China (2017YFC0211600, 2017YFC0211601).

6.
J Affect Disord ; 295: 703-710, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517243

RESUMO

BACKGROUND: Given that multimorbidity is strongly associated with disability in activities of daily living (ADL) and the mechanism still remains unclear, this study sought to investigate the mediating effect of depressive symptoms on such association. METHODS: A longitudinal dataset was drawn from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2015), including 3951 adults aged 45 years and above. By sex, logistic regression and mediation analysis (the Karlson, Holm, and Breen Method) were employed. RESULTS: The presence of multimorbidity was associated with increased odds of having depressive symptoms and developing ADL disability, and depressive symptoms was significantly associated with ADL disability among middle-aged and older women. Mediation analysis illustrated that depressive symptoms accounted for 6.36% of the effect of multimorbidity on ADL disability in women. LIMITATIONS: Results might not generalize to all middle-aged and older Chinese due to missing data on depressive symptoms and ADL. CONCLUSIONS: Multimorbidity increased the likelihood of ADL disability onset partially through depressive symptoms in middle-aged and older women, suggesting that emphasizing mental wellness of females with multimorbidity are necessary to prevent impairments in physical function.


Assuntos
Atividades Cotidianas , Pessoas com Deficiência , Adulto , Idoso , China/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Multimorbidade , Aposentadoria
7.
J Neurophysiol ; 126(4): 1148-1158, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34495792

RESUMO

During the noninvasive evaluation phase for refractory epilepsy, the localization of the epileptogenic zone (EZ) is essential for the surgical protocols. Confirmation of laterality is required when the preoperative evaluation limits the EZ to bilateral anterior temporal lobes or bilateral frontal lobes. High-frequency oscillations (HFOs) are considered to be promising biological markers for the EZ. However, a large number of studies on HFOs stem from intracranial research. There were few quantitative measures for scalp HFOs, so we proposed a new method to quantify and analyze scalp HFOs. This method was called the "scalp-HFO index" (HI) and calculated in both the EZ and non-EZ. The calculation was based on the numbers and spectral power of scalp HFOs automatically detected. We labeled the brain lobes involved in the EZ as regions of interest (ROIs). The HIs based on the ripple numbers (n-HI) and spectral power (s-HI) were significantly higher in the ROI than in the contra-ROI (P = 0.012, P = 0.003), indicating that HIs contributed to the lateralization of EZ. The sensitivity and specificity of n-HI for the localization of the EZ were 90% and 79.58%, respectively, suggesting that n-HI was valuable in localizing the EZ. HI may contribute to the implantation strategy of invasive electrodes. However, few scalp HFOs were recorded when the EZ was located in the medial cortex region.NEW & NOTEWORTHY We proposed the scalp-high-frequency oscillation (HFO) index (HI) as a quantitative assessment method for scalp HFOs to locate the epileptogenic zone (EZ). Our results showed that the HI in regions of interest (ROIs) was significantly higher than in contra-ROIs. Sensitivity and specificity of HI based on ripple rates (n-HI) for EZ localization were 90% and 79.58%, respectively. If the n-HI of the brain region was >1.35, it was more likely to be an epileptogenic region. Clinical application of HIs as an indicator may facilitate localization of the EZ.

8.
Int J Gen Med ; 14: 4529-4534, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421311

RESUMO

Background: Neonatal ventilator-associated pneumonia (NVAP) is one of the main infections acquired in hospitals, and soluble triggering receptors expressed on myeloid cells-1 (sTREM-1) are a TREM-1 subtype that can be released into the blood or bodily fluids during an infection. Methods: The patients included in the present study were divided into three groups: the NVAP group, the first control group, and the second control group (n = 20, each). Children requiring respiratory treatment were assigned to the NVAP group, newborns who received mechanical ventilation and had neonatal respiratory distress syndrome were assigned to the first control group, and newborns with normal X-ray and electrocardiogram results but no non-pulmonary infection was assigned to the second control group. The blood and bronchoalveolar lavage fluid (BALF) sTREM-1 levels in all newborns were analyzed. Results: The acute-phase blood and BALF sTREM-1 levels were significantly higher in the NVAP group than in the first control group, and the blood sTREM-1 expression level was lower in the second control group than in the NVAP group. Conclusion: The present results suggest that sTREM-1 might be a useful biomarker for NVAP prediction in the Department of Pediatrics.

9.
Opt Lett ; 46(16): 3881-3884, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388765

RESUMO

For the design of achromatic metalenses, one key challenge is to accurately realize the wavelength dependent phase profile. Because of the demand of tremendous simulations, traditional methods are laborious and time consuming. Here, a novel deep neural network (DNN) is proposed and applied to the achromatic metalens design, which turns complex design processes into regression tasks through fitting the target phase curves. During training, x-y projection pairs are put forward to solve the phase jump problem, and some additional phase curves are manually generated to optimize the DNN performance. To demonstrate the validity of our DNN, two achromatic metalenses in the near-infrared region are designed and simulated. Their average focal length shifts are 2.6% and 1.7%, while their average relative focusing efficiencies reach 59.18% and 77.88%.

10.
Health Policy Plan ; 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34379765

RESUMO

High drug costs are putting pressures on health care budgets and posing an obstacle for China to achieve universal coverage. Policies such as the direct price ceiling, and the Essential Medicines Program-with the Zero Markup Drug Policy (ZMDP) one key component-were implemented, coming out with limited evidence for a success. As a benchmark of China's recent health reform, Sanming city initiated the ZMDP in January 2013; and further piloted the first reference pricing (RP) policy in China in September 2014, with the intention to dis-incentivize the use of costly original drugs. In this study, we used hospital-based drug procurement data of 14 drug substances that were subjected to the RP, from four hospitals in Sanming and a neighbouring city Longyan, between 2012 and 2016. Adopting the difference-in-difference (DID) approach, we evaluated the impacts of the RP together with the ZMDP. On the one hand, we found that the ZMDP had no impact on drugs' procurement prices, volumes and costs. While on the other hand, we found that the introduction of RP was not associated with changes in unit prices for the 14 drugs in Sanming. However, the RP pilot was associated with a 25.9% [95% confidence interval (CI), 12.9-37.0%] decrease in monthly drug procurement volumes and a 47.7% (95% CI, 33.7-58.7%) decrease in the total drug costs. In particular, it reduced the procurement volumes of original drugs by 56.8% (95% CI, 47.0-64.7%). Subgroup analyses by hospital level and therapeutic class found similar results. We draw lessons for the Chinese government to experiment RP on a larger scale, considering the development and effective regulation of the generic market. This is a first report on the effects of RP in China, Asia and middle-income countries.

11.
Nanoscale Res Lett ; 16(1): 132, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34406517

RESUMO

Most Alzheimer's disease drugs do not work efficiently because of the blood-brain barrier. Therefore, we designed a new nanopreparation (PS-DZP-CHP): cholesterol-modified pullulan (CHP) nanoparticle with polysorbate 80(PS) surface coverage, as donepezil (DZP) carrier to realize brain tissue delivery. By size analysis and isothermal titration calorimetry, we chose the optimal dosing ratio of the drug with nanomaterials (1:5) and designed a series of experiments to verify the efficacy of the nanoparticles. The results of in vitro release experiments showed that the nanoparticles can achieve continuous drug release within 72 h. The results of fluorescence observation in mice showed a good brain targeting of PS-DZP-CHP nanoparticles. Furthermore, the nanoparticle can enhance the drug in the brain tissue concentration in mice. DZP-CHP nanoparticles were used to pretreat nerve cells with Aß protein damage. The concentration of lactate dehydrogenase was determined by MTT, rhodamine 123 and AO-EB staining, which proved that DZP-CHP nanoparticles had a protective effect on the neurotoxicity induced by Aß25-35 and were superior to free donepezil. Microthermal perpetual motion meter test showed that PS-DZP-CHP nanoparticles have an affinity with apolipoprotein E, which may be vital for this nanoparticle targeting to brain tissue.

12.
Arch Public Health ; 79(1): 157, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34462011

RESUMO

BACKGROUNDS: Non-communicable diseases (NCDs) have become a priority public health issue. The aim of this study was to examine whether socio-economic inequalities exist in chronic disease management among Chinese adults, and whether the relationship between SES and chronic disease management mediated by social capital. METHODS: We used combined data from China Health and Retirement Longitudinal Study (CHARLS). A total of 19,291 subjects, including 14,905 subjects from 2011 survey, 2036 subjects from 2013, and 2350 subjects from 2015 was included in this study. RESULTS: Subjects living in urban setting, with higher education attainment and economic status were more likely to have annual health checks, and to be diagnosed for those with hypertension, diabetes and dyslipidemia (all P < 0.05). Social participation could mediate the association between social economic status (SES) and annual health checks, diagnosis of hypertension and dyslipidemia, and health education of hypertension. Health checks could mediate the association between social participation and the diagnosis of hypertension, diabetes and dyslipidemia. The proportions of mediation were 17.5, 23.9 and 8.9%, respectively. There were no mediating effects observed from cognitive social capital variable-perceived helpfulness. CONCLUSION: It is necessary to deeply reform our social security system and enhance the social capital construction to promote those low SES people's physical health.

13.
Histol Histopathol ; : 18360, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34291441

RESUMO

Lot of attention had been paid to the role of circular RNAs (circRNAs) in carcinogenesis recently. However, knowledge about circRNAs in NSCLC development is far from satisfactory. In this study, we aimed to provide a novel insight into the circRIP2 in NSCLC development. We used NSCLC tissues, as well as cell lines to elucidate the expression and location of circRIP2 in NSCLC. We also established the circRIP2 overexpression cells A549-circRIP2 and repression cells HCC827-shcircRIP2 for further functional and mechanism studies. The pro-tumorigenic role of circRIP2 was tested by using CCK-8, BrdU and transwell assays. The interaction between circRIP2 and miR-671-5p were validated by luciferase reporter assay, RIP assay, as well as RNA pull down assay. We showed circRIP2 is differentially expressed NSCLC, and acted as a predictor for overall survival (OS) and disease-free survival (DFS). CircRIP2 promoted NSCLC progression by acting as a miRNA sponge for miR-671-5p, thus facilitating its target gene FOXM1 expression. Targeting circRIP2 could be potentially beneficial for NSCLC patients in the future.

14.
Lancet Reg Health West Pac ; 6: 100075, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34327408

RESUMO

Background: We evaluated a large-scale pilot program in Shaanxi Province, western rural China, which integrated prenatal screening interventions for congenital abnormalities into routine antenatal programs. Methods: We surveyed 1,597 mothers who gave birth between 2009 and 2016. Adopting the interrupted time-series design, we evaluated the program's impact on awareness, coverage, and cost, by comparing two counties with only supply-side policies, and two counties from the neighbouring province with no policies; and among the two counties with both supply- and demand-side policies and the two counties with only supply-side policies. We adjusted the sampling procedure and women's background characteristics. We conducted subgroup analyses by women's education. Findings: After one year of implementation, the coverage of prenatal foetal aneuploidies and B-ultrasound screening rose by 25.0% and 23.5%. The program's supply-side policies attributed to 17.2 percentage points (90%CI 7.8-26.6%) and 27.3 percentage points (90%CI 16.2-38.5%) in coverage, and contributed to a higher median cost of 796.5RMB (90%CI 595.5-997.5). These significantly affected women with secondary education and above. However, the program's demand-side measures, that is, vouchers, seemed to be effective only in the mountainous regions, which raised awareness, and increased coverage of prenatal foetal aneuploidies screening by 28.6 percentage points (90%CI 13.4-43.8%), while not increasing costs. These significantly affected women with primary education and below. Education-related inequalities widened post-program in counties with only supply-side policies, but no inequalities existed in counties with demand-side policies. Interpretation: Shaanxi's program made a pilot study to other provinces of China to integrate antenatal services. Government subsidies might be more effective in targeting specific geographic locations and people with primary education and lower.

15.
Stem Cell Res Ther ; 12(1): 395, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256832

RESUMO

BACKGROUND: Hepatic steatosis is a big hurdle to treat type 2 diabetes (T2D). Fasting-mimicking diet (FMD) has been shown to be an effective intervention in dyslipidemia of T2D. However, fasting may impair the normal glucose metabolism. Human umbilical cord-derived mesenchymal stem cell (UC-MSC) transplantation has been discovered to regulate immune reactions and reduce hyperglycemia in diabetes. However, the effect of UC-MSCs on improving the lipid metabolism disorder is not quite satisfactory. We have investigated the efficacy comparison and interaction between FMD and UC-MSC infusion, aiming to establish effective T2D therapies and explore its mechanism. METHODS: C57/BL6 mice were fed with high-fat diet (HFD) to induce a diet-induced obese (DIO) mouse model. Leptin receptor-deficient (db/db) mice were used for follow-up experiments. DIO or db/db mice were divided into 4 groups: phosphate buffer saline (PBS), UC-MSCs, FMD, and UC-MSCs + FMD. At the end of the study period, mice were fasted and sacrificed, with the measurement of physiological and biochemical indexes. In addition, the fresh liver, skin, and white adipose tissue were analyzed by histology. RESULTS: FMD restored the lipid metabolism in DIO mice, whereas its capacity to rescue hyperglycemia was uncertain. Infusion of UC-MSCs was effective in T2D glycemic control but the impact on dyslipidemia was insufficient. Furthermore, both the glucose and the lipid alterations of DIO and db/db mice recovered after UC-MSCs combined with FMD. It was proved that UC-MSCs promoted FMD effects on ameliorating hyperglycemia and restoring the lipid metabolism in T2D mice, while FMD had little promotion effect on UC-MSCs. Mechanistically, we discovered that UC-MSC infusion significantly modulated systematic inflammatory microenvironment, which contributed to concerted actions with FMD. CONCLUSIONS: We established a strategy that combined UC-MSC infusion and FMD and was effective in treating T2D, which provided potential approaches for developing novel clinical T2D therapies.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Diabetes Mellitus Tipo 2/terapia , Jejum , Controle Glicêmico , Camundongos , Cordão Umbilical
16.
Exp Neurol ; 344: 113814, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34280452

RESUMO

The functional roles of microRNAs (miRNAs) have been studied in various diseases, including hypoxic-ischemic brain damage (HIBD). However, changes in the expression of miRNAs and the underlying mechanisms in the pineal gland during HIBD remain unknown. Based on the previous study by microRNA array, hundreds of miRNAs showed altered expression patterns in the pineal gland in a rat model of HIBD. MiR-375-3p was found to be significantly upregulated and abundant in the pineal gland. Further investigation in an in vitro HI model of pinealocytes showed that miRNA-375 exacerbated the damage to pineal function. After oxygen-glucose deprivation / reoxygenation (OGD/R), miR-375-3p expression increased, while aralkylamine N-acetyltransferase (AANAT) expression and melatonin (MT) secretion decreased. Overexpression of miRNA-375 in pinealocytes aggravated the influence of OGD/R on AANAT expression and MT secretion. Because miRNA-375 overexpression in pinealocytes induced decreased rasd1 mRNA and protein expression, rasd1 may mediate the effect of miR-375-3p on pineal function. Furthermore, miR-375-3p aggravated the cognitive impairment caused by HIBD in rats, as observed by Morris water maze test, and also affected emotion and circadian rhythm in HIBD-treated rats. Thus, miR-375-3p may be a key regulatory molecule in the pineal gland following HIBD, and targeting of miR-375-3p may represent a new strategy for the treatment of HIBD.

17.
ACS Nano ; 15(6): 9924-9934, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34096697

RESUMO

Dual-modal fluorescence and magnetic resonance imaging (FLI/MRI) is important for the early diagnosis of malignant tumors. However, facile and opportune strategies to synergistically enhance fluorescence intensity and magnetic resonance (MR) contrast have rarely been reported. Herein, we present a facile strategy using albumin aggregates (AAs) to synergistically enhance the fluorescence intensity by aggregation-induced emission (AIE) and MR contrast with prolonged rotational correlation time (τR) of Gd(III) chelates and the diffusion correlation time (τD) of surrounding water molecules. The amphiphilic dual-modal FLI/MRI probe of NGd was facilely loaded into albumin pockets and then formed AAs to generate a supramolecular structure of NGd-albumin aggregates (NGd-AAs), which show excellent biocompatibility and biosafety, and exhibit superior fluorescence quantum yield and r1 over NGd with 6- and 8-fold enhancement, respectively. Moreover, compared with the clinical MRI contrast agent Gd-DOTA, r1 of NGd-AAs showed a 17-fold enhancement. Therefore, NGd-AAs successfully elicited high-performance dual-modal FLI/MRI in vitro and in vivo and high contrast MR signals were observed in the liver and tumor after intravenous injection of NGd-AAs at a dosage of 6 µmol Gd(III)/kg body weight. This generic and feasible strategy successfully realized a synergistic effect for dual-modal FLI/MRI.


Assuntos
Meios de Contraste , Neoplasias , Albuminas , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
18.
Inorg Chem ; 60(12): 8581-8591, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34096270

RESUMO

The coordination between a ligand and a metal is a spontaneous and uncontrollable process. In this Article, we successfully observe the formation of metal coordination in a triphenylamine-functionalized salicylaldehyde Schiff base with a copper(II) ion. The ligand TPA-Py first reacts with Cu2+ in a stepwise process to afford the dynamic complex TPA-Py@Cu2+ ([ligand]:[Cu2+] = 1:1), which further reacts with an extra copper(II) ion to afford 2TPA-Py@4Cu2+ with the following stepwise (or cumulative) stability constants: K1 = 4.0694 × 103 and K2 = 1.0761 × 106, respectively. The entire metal coordination process can be visualized, and the coordination mode of the probe toward copper was further evaluated by ultraviolet-visible/fluorescence spectra, single-crystal X-ray diffraction, density functional theory calculations, high-resolution mass spectra, and nuclear magnetic resonance spectroscopic titrations. Compound TPA-Py exhibited excellent sensitivity and specificity toward copper(II) ions in THF/water media with a low limit of detection of 2.687 × 10-7 mol L-1. In addition, TPI-An-Py can be applied to the detection of Cu2+ in real samples with satisfactory recoveries in the range of 100-112% in lake water and 98-101% in tap water. This Article not only reports an excellent fluorescence probe for copper(II) ion detection but also presents an instance for more fully understanding the metal coordination process.

19.
Adv Mater ; 33(31): e2007100, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34117808

RESUMO

Hydrogen economy has emerged as a very promising alternative to the current hydrocarbon economy, which involves the process of harvesting renewable energy to split water into hydrogen and oxygen and then further utilization of clean hydrogen fuel. The production of hydrogen by water electrolysis is an essential prerequisite of the hydrogen economy with zero carbon emission. Among various water electrolysis technologies, alkaline water splitting has been commercialized for more than 100 years, representing the most mature and economic technology. Here, the historic development of water electrolysis is overviewed, and several critical electrochemical parameters are discussed. After that, advanced nonprecious metal electrocatalysts that emerged recently for negotiating the alkaline oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are discussed, including transition metal oxides, (oxy)hydroxides, chalcogenides, phosphides, and nitrides for the OER, as well as transition metal alloys, chalcogenides, phosphides, and carbides for the HER. In this section, particular attention is paid to the catalyst synthesis, activity and stability challenges, performance improvement, and industry-relevant developments. Some recent works about scaled-up catalyst synthesis, novel electrode designs, and alkaline seawater electrolysis are also spotlighted. Finally, an outlook on future challenges and opportunities for alkaline water splitting is offered, and potential future directions are speculated.

20.
Risk Manag Healthc Policy ; 14: 1843-1853, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994815

RESUMO

Background: The Coronavirus Diseases (COVID-19) pandemic is a global public health challenge and provides an opportunity to investigate the unclear relationship between risk perception, social support, and mental health. This study aims to examine the association between risk perception and mental health while taking social support as a moderator. Methods: An online cross-sectional study recruiting 2993 participants was conducted in China, from 1st to 10th, February 2020. The relationship between risk perception, social support, and mental health was examined using multivariate linear regression analyses. Results: This study indicated that risk perception was associated with a higher level of mental health symptoms. The subscale "Perceived uncontrollability" seemed to present a stronger correlation with depressive symptoms (Beta=0.306) and post-traumatic stress disorder (PTSD) symptoms (Beta=0.318) than the subscale "Perceived Severity" did. Moreover, social support moderated the relationship between perceived uncontrollability and mental health symptoms. Conclusion: In the context of the COVID-19 pandemic, it is necessary to design mental health strategies and programs from a risk perception perspective (more mental health strategies should be delivered to build reasonable risk perception), while social support from family and friends may be protective to against depressive symptoms and PTSD symptoms. There is a demand for mental health intervention from a risk perception perspective.

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