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1.
Life (Basel) ; 11(3)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801920

RESUMO

Ferroptosis is characterized as a novel form of regulated cell death, which is initiated by the lethal accumulation of lipid peroxidation catalyzed by cellular labile free iron. This iron driven cell death sharply differs from other well characterized forms of regulated cell death at morphological, genetic and biochemical levels. Increasing research has elaborated a high relevance between dysregulated ferroptosis and the pathogenesis of degenerative diseases and organs injury in human patients. Additionally, targeted induction of ferroptosis is considered as a potentially therapeutic design for the clinical intervention of other therapy-resistant cancers. It is well understood that mitochondria, the cellular powerhouse, determine several types of regulated cell death. Recently, compromised mitochondrial morphology and functionalities have been primarily formulated in ferroptosis. Several mitochondria associated proteins and metabolic processes have been elaborated to fine-tune ferroptotic program. Herein, we critically review the recent advances in this booming field, with focus on summarizing the multifaceted mitochondrial regulation of ferroptosis and providing a perspective on the potential biochemical basis. Finally, we are attempting to shed light on an integrative view on the possibility of mitochondria- and ferroptosis-targeting therapeutics as novel treatment designs for the intervention of ferroptosis related diseases.

2.
Materials (Basel) ; 14(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809150

RESUMO

The effectiveness of the mechanism of precipitation strengthening in metallic alloys depends on the shapes of the precipitates. Two different material systems are considered: tetragonal γ'' precipitates in Ni-based alloys and tetragonal θ' precipitates in Al-Cu-alloys. The shape formation and evolution of the tetragonally misfitting precipitates was investigated by means of experiments and phase-field simulations. We employed the method of invariant moments for the consistent shape quantification of precipitates obtained from the simulation as well as those obtained from the experiment. Two well-defined shape-quantities are proposed: (i) a generalized measure for the particles aspect ratio and (ii) the normalized λ2, as a measure for shape deviations from an ideal ellipse of the given aspect ratio. Considering the size dependence of the aspect ratio of γ'' precipitates, we find good agreement between the simulation results and the experiment. Further, the precipitates' in-plane shape is defined as the central 2D cut through the 3D particle in a plane normal to the tetragonal c-axes of the precipitate. The experimentally observed in-plane shapes of γ''-precipitates can be quantitatively reproduced by the phase-field model.

3.
Materials (Basel) ; 14(5)2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33800245

RESUMO

The effects of anisotropic interfacial properties and heterogeneous elasticity on the growth and ripening of plate-like θ'-phase (Al2Cu) in Al-1.69 at.% Cu alloy are studied. Multi-phase-field simulations are conducted and discussed in comparison with aging experiments. The precipitate/matrix interface is considered to be anisotropic in terms of its energy and mobility. We find that the additional incorporation of an anisotropic interfacial mobility in conjunction with the elastic anisotropy result in substantially larger aspect ratios of the precipitates closer to the experimental observations. The anisotropy of the interfacial energy shows comparably small effect on the precipitate's aspect ratio but changes the interface's shape at the rim. The effect of the chemo-mechanical coupling, i.e., the composition dependence of the elastic constants, is studied as well. We show that the inverse ripening phenomenon, recently evidenced for δ' precipitates in Al-Li alloys (Park et al. Sci. Rep. 2019, 9, 3981), does not establish for the θ' precipitates. This is because of the anisotropic stress fields built around the θ' precipitates, stemming from the precipitate's shape and the interaction among different variants of the θ' precipitate, that disturb the chemo-mechanical effects. These results show that the chemo-mechanical effects on the precipitation ripening strongly depend on the degree of sphericity and elastic isotropy of the precipitate and matrix phases.

4.
BMC Plant Biol ; 21(1): 152, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33761884

RESUMO

BACKGROUND: Prunus pedunculata Pall, the deciduous shrub of Amygdalus subgenus in Rosaceae, is a new kind of desert oil-bearing tree. It has a long story of being planted in the West and North of China for sand fixation and desert control. In addition, the seeds of P. pedunculata are rich of oil, especially the monounsaturated fatty acid and polyunsaturated fatty acid. However, little is known about the molecular mechanisms of oil accumulation during the seed development of P. pedunculata. RESULTS: The seeds of P. pedunculata from three independent plants at 10, 18, 24, 31, 39, 45, 59 and 73 days after flowering (DAF) were obtained and the oil compositions were evaluated. It showed that oleic acid was the dominant type of oil content in the mature seeds (from 32.724% at 10DAF to 72.06% at 73DAF). Next, transcriptome sequencing for the developing seeds produced 988.795 million high quality reads and TRINITY assembled 326,271 genes for the first transcriptome for P. pedunculata. After the assembled transcriptome was evaluated by BUSCO with 85.9% completeness, we identified 195,342, 109,850 and 121,897 P. pedunculata genes aligned to NR, GO and KEGG pathway databases, respectively. Then, we predicted 23,229 likely proteins from the assembled transcriptome and identified 1917 signal peptides and 5512 transmembrane related proteins. In the developing seeds we detected 91,362 genes (average FPKM > 5) and correlation analysis indicated three possible development stages - early (10 ~ 24DAF), middle (31 ~ 45DAF) and late (59 ~ 73DAF). We next analyzed the differentially expressed genes (DEGs) in the developing seeds. Interestingly, compared to 10DAF the number of DEGs was increased from 4406 in 18DAF to 27,623 in 73DAF. Based on the gene annotation, we identified 753, 33, 8 and 645 DEGs related to the fatty acid biosynthesis, lipid biosynthesis, oil body and transcription factors. Notably, GPAT, DGD1, LACS2, UBC and RINO were highly expressed at the early development stage, ω6-FAD, SAD, ACP, ACCA and AHG1 were highly expressed at the middle development stage, and LACS6, DGD1, ACAT1, AGPAT, WSD1, EGY2 and oleosin genes were highly expressed at the late development stage. CONCLUSIONS: This is the first time to study the developing seed transcriptome of P. pedunculata and our findings will provide a valuable resource for future studies. More importantly, it will improve our understanding of molecular mechanisms of oil accumulation in P. pedunculata.

5.
EMBO Rep ; 22(3): e50629, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33554448

RESUMO

Mitophagy is an essential cellular autophagic process that selectively removes superfluous and damaged mitochondria, and it is coordinated with mitochondrial biogenesis to fine tune the quantity and quality of mitochondria. Coordination between these two opposing processes to maintain the functional mitochondrial network is of paramount importance for normal cellular and organismal metabolism. However, the underlying mechanism is not completely understood. Here we report that PGC-1α and nuclear respiratory factor 1 (NRF1), master regulators of mitochondrial biogenesis and metabolic adaptation, also transcriptionally upregulate the gene encoding FUNDC1, a previously characterized mitophagy receptor, in response to cold stress in brown fat tissue. NRF1 binds to the classic consensus site in the promoter of Fundc1 to upregulate its expression and to enhance mitophagy through its interaction with LC3. Specific knockout of Fundc1 in BAT results in reduced mitochondrial turnover and accumulation of functionally compromised mitochondria, leading to impaired adaptive thermogenesis. Our results demonstrate that FUNDC1-dependent mitophagy is directly coupled with mitochondrial biogenesis through the PGC-1α/NRF1 pathway, which dictates mitochondrial quantity, quality, and turnover and contributes to adaptive thermogenesis.

6.
Entropy (Basel) ; 22(7)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-33286526

RESUMO

Diabetic peripheral neuropathy (DPN) is a very common neurological disorder in diabetic patients. This study presents a new percussion-based index for predicting DPN by decomposing digital volume pulse (DVP) signals from the fingertip. In this study, 130 subjects (50 individuals 44 to 89 years of age without diabetes and 80 patients 37 to 86 years of age with type 2 diabetes) were enrolled. After baseline measurement and blood tests, 25 diabetic patients developed DPN within the following five years. After removing high-frequency noise in the original DVP signals, the decomposed DVP signals were used for percussion entropy index (PEIDVP) computation. Effects of risk factors on the incidence of DPN in diabetic patients within five years of follow-up were tested using binary logistic regression analysis, controlling for age, waist circumference, low-density lipoprotein cholesterol, and the new index. Multivariate analysis showed that patients who did not develop DPN in the five-year period had higher PEIDVP values than those with DPN, as determined by logistic regression model (PEIDVP: odds ratio 0.913, 95% CI 0.850 to 0.980). This study shows that PEIDVP can be a major protective factor in relation to the studied binary outcome (i.e., DPN or not in diabetic patients five years after baseline measurement).

7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(10): 1155-1163, 2020 Oct 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33268575

RESUMO

OBJECTIVES: Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) controls mitochondrial biogenesis, but its role in cardiovascular diseases is unclear. The purpose of this study is to explore the effect of PGC1α on myocardial ischemia-reperfusion injury and the underlying mechanisms. METHODS: The transverse coronary artery of SD rat was ligated for 30 minutes followed by 2 hours of reperfusion. Triphenyltetrazolium chloride (TTC) staining was performed to measure the area of myocardial infarction. Immunohistochemistry and Western blotting were used to detect the PGC1α expression in myocardium. The rat cardiomyocyte H9C2 was subjected to hypoxia/reoxygenation (H/R) with the knockdown of PGC1α or hypoxia- inducible factor 1α (HIF-1α), or with treatment of metformin. Western blotting was used to detect the expression of PGC1α, HIF-1α, p21, BAX, and caspase-3. CCK-8 was performed to detect cell viability, and flow cytometry was used to detect apoptosis and mitochondrial superoxide (mitoSOX) release. RT-qPCR was used to detect the mRNA expression of PGC1α and HIF-1α. Besides, chromatin immunoprecipitation (ChIP)-qPCR and luciferase reporter gene assay were applied to detect the transcriptional regulation effect of HIF-1α on PGC1α. RESULTS: After I/R, the PGC1α expression was increased in infarcted myocardium. H/R induced H9C2 cell apoptosis (P<0.001). The release of mitoSOX (P<0.001) and protein expression of PGC1α, and apoptosis-related p21, BAX, and caspase-3 were increased. However, knockdown of PGC1α reduced apoptosis (P<0.01) and mitoSOX release (P<0.001), and decreased protein expression of apoptosis-related gene. HIF-1α is bound to the promoter region of PGC1α. Knockdown of HIF-1α inhibited the transcription and protein expression of PGC1α and further to reduce the apoptosis (all P<0.001) and mitoSOX release (P<0.01). While overexpression of PGC1α reversed the effects caused by HIF-1α knockdown (all P<0.001). Metformin effectively reduced H/R-induced apoptosis (P=0.013), mitoSOX release (P<0.001), HIF-1α, PGC1α and apoptosis-related protein expression, recovered the cell viability (P<0.001), and reduced myocardial infarction (P=0.003). CONCLUSIONS: After I/R, HIF-1α up-regulates the expression of PGC1α, leading to an increase in ROS production and aggravation of injury. Metformin can inhibit the accumulation of HIF-1α during hypoxia and effectively protect myocardium from ischemia/reperfusion injury.

9.
Int J Neurosci ; : 1-12, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33045891

RESUMO

Objective Microglia activation is an essential pathological mechanism of spinal cord ischemia-reperfusion injury (SCIRI). Previous studies showed dexmedetomidine (DEX) could alleviate SCIRI while the mechanism was not clear. This study aims to investigate the role of DEX in microglial and clarify the underlying.Methods The motion function of mice was quantified using the Basso Mouse Scale for Locomotion. The expression of long non-coding RNA (lncRNA) small nucleolar RNA host gene 14 (SNHG14) was determined by qRT-PCR. The expression of high-mobility group box 1 (HMGB1) was measured by western blot. The activation of microglia was evaluated by the expression of ED-1 and the level of TNF-α and IL-6. The interplay between SNHG14 and HMGB1 was confirmed with RNA pull-down and RIP assay. The stability of HMGB1 was measured by ubiquitination assay and cycloheximide-chase assay.Results DEX inhibited microglial activation and down-regulated SNHG14 expression in SCIRI mice and oxygen and glucose deprivation/reoxygenation (OGD/R)-treated primary microglia. Functionally, SNHG14 overexpression reversed the inhibitory effect of DEX on OGD/R-induced microglial activation. Further investigation confirmed that SNHG14 bound to HMGB1, positively regulated HMGB1 expression by enhancing its stability. In addition, the silence of HMGB1 eliminated the pro-activation impact of SNHG14 overexpression on DEX-treated microglia under the OGD/R condition. Finally, in vivo experiments showed SNHG14 overexpression abrogated the therapeutic effect of DEX on SCIRI mice by up-regulating HMGB1.Conclusion DEX accelerated HMGB1 degradation via down-regulating SNHG14, thus inhibiting microglial activation in SCIRI mice.

10.
J Reprod Immunol ; 142: 103192, 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32950783

RESUMO

BACKGROUND: Neisseria gonorrhoeae (N.g) is Gram-negative bacteria and can lead to endometritis in female. Toll-like receptors regulate immune response in various diseases. However, the roles of TLR2 and TLR4 in. Neisseria gonorrhoeae-induced infection damage in human endometrial epithelia were investigated. METHODS: hEECs were infected with N.g (MOI 10 and 100) and cell viability and apoptosis were measured by CCK8 and flow cytometry assays in both infected groups with the uninfected normal hEECs as negative control. TLR2/TLR4 proteins were measured by ELISA method. Pro-inflammatory markers NLRP3, PGES (PGE2) and TNF-α were assessed by RT-qPCR (mRNA expression) and Elisa (protein concentrations). Transfection assays were performed to up- or down- regulate expression of TLR2 and TLR4 so as to study the functions of TLR2/TLR4 in. N.g-infected hEECs, followed by apoptosis and inflammation assessment. Similarly, we explored the interactions between TLR2/TLR4 and Nrf2/NF-κB/p65 by knocking down TLR2/TLR4 to detect the signaling and further regulating the signaling to evaluate TLR2/ TLR4, apoptosis and inflammation in cells. RESULTS: N.g suppressed cell viabilities and induced cell apoptosis and inflammation. TLR2/TLR4 downregulation inhibited the infection damage. Nrf2 was activated while NF-κB/p65 was depleted as TLR2/ TLR4 was knocked down. Activation of Nrf2 and inhibition of NF-κB resulted in decrease of TLR2/TLR4, which could retard apoptosis and inflammation induced by N.g infection. CONCLUSION: TLR2/TLR4 depletion could alleviate the N.g-infected hEECs via Nrf2/NF-kB signaling, suggesting that TLR2/TLR4 inhibitors might serve as a treatment to reduce N.g infection in human endometrial epithelia.

11.
Angew Chem Int Ed Engl ; 59(37): 15968-15973, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452143

RESUMO

In situ exsolution of metal nanoparticles in perovskite under reducing atmosphere is employed to generate a highly active metal-oxide interface for CO2 electrolysis in a solid oxide electrolysis cell. Atomic-scale insight is provided into the exsolution of CoFe alloy nanoparticles in La0.4 Sr0.6 Co0.2 Fe0.7 Mo0.1 O3-δ (LSCFM) by in situ scanning transmission electron microscopy (STEM) with energy-dispersive X-ray spectroscopy and DFT calculations. The doped Mo atoms occupy B sites of LSCFM, which increases the segregation energy of Co and Fe ions at B sites and improves the structural stability of LSCFM under a reducing atmosphere. In situ STEM measurements visualized sequential exsolution of Co and Fe ions, formation of CoFe alloy nanoparticles, and reversible exsolution and dissolution of CoFe alloy nanoparticles in LSCFM. The metal-oxide interface improves CO2 adsorption and activation, showing a higher CO2 electrolysis performance than the LSCFM counterparts.

12.
Clin Cancer Res ; 26(16): 4302-4312, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32332018

RESUMO

PURPOSE: To identify a predictive biomarker of sorafenib for hepatocellular carcinoma personalized therapy. EXPERIMENTAL DESIGN: The patients treated with or without sorafenib after hepatocellular carcinoma recurrence from multicenters were matched with propensity score matching analysis. The expression levels of Fms-like tyrosine kinase 3 (FLT3) in hepatocellular carcinoma specimens of the matched patients (n = 276) were analyzed by IHC. The optimal cut-off point of FLT3 levels for overall survival (OS) was defined via Cutoff Finder. Subgroup analysis of OS was employed to investigate the association between FLT3 levels and sorafenib benefit. The predictive value was assessed via Cox regression models with an interaction term. Hepatocellular carcinoma and paratumoral normal tissues were used to investigate the expression and copy-number variation of FLT3. Patient-derived xenograft (PDX) models were used to confirm the association between FLT3 levels and sorafenib response. RESULTS: Patients with FLT3-high hepatocellular carcinoma exhibited a superior OS upon sorafenib treatment. High FLT3 levels were predictive of sorafenib benefit in terms of OS (P interaction = 0.00006). Copy-number losses and decreased expression of FLT3 in hepatocellular carcinoma were detected in about 64% of patients. Moreover, the PDXs derived from tumors with high FLT3 levels also displayed a better response to sorafenib. CONCLUSIONS: Sorafenib may be able to delay tumor progression in patients with FLT3-high hepatocellular carcinoma. This potential biomarker needs to be further validated in independent cohorts prior to helping stratify patients for precision therapy in advanced hepatocellular carcinoma.

13.
Cell Res ; 30(6): 551-552, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32284560

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

15.
Emerg Microbes Infect ; 9(1): 263-274, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31997725

RESUMO

In the present study, a total of 1102304 serum samples were collected to detected human brucellosis between the years 2012 and 2016 in Inner Mongolia. Overall, an average of 3.79% anti-Brucella positive in Inner Mongolia was presented but the range of positive rates were among 0.90 to 7.07% in 12 regions. Seroprevalence of human brucellosis increased gradually from 2012 to 2016. However, the incidence rate of human brucellosis showed a declining trend. One hundred and seven Brucella strains were isolated and identified as B. melitensis species, and B. melitensis biovar 3 was the predominant biovar. MLVA-11 genotypes 116 was predominant and had crucial epidemiology to the human population. All 107 strains tested were sorted into 75 MLVA-16 genotypes, with 54 single genotypes representing unique isolates. This result revealed that these Brucellosis cases had epidemiologically unrelated and sporadic characteristics. The remaining 21 shared genotypes among two to four strains, confirming the occurrence of cross-infection and multiple outbreaks. Extensive genotype-events were observed between strains from this study and Kazakhstan, Mongolia, and Turkey, these countries were key members of the grassland silk road. Long-time trade in small ruminants (sheep) in these countries has possibly promoted the spread of Brucella spp. in these regions.


Assuntos
Brucella/genética , Brucelose/epidemiologia , Alelos , China/epidemiologia , Genótipo , Humanos , Filogenia , Estudos Soroepidemiológicos , Fatores de Tempo
16.
World J Emerg Med ; 11(1): 37-47, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893002

RESUMO

BACKGROUND: Penehyclidine is a newly developed anticholinergic agent. We aimed to investigate the role of penehyclidine in acute organophosphorus pesticide poisoning (OP) patients. METHODS: We searched the Pubmed, Cochrane library, EMBASE, Chinese National Knowledge Infrastructure (CNKI), Chinese Biomedical literature (CBM) and Wanfang databases. Randomized controlled trials (RCTs) recruiting acute OP patients were identified for meta-analysis. Main outcomes included cure rate, mortality rate, time to atropinization, time to 60% normal acetylcholinesterase (AchE) level, rate of intermediate syndrome (IMS) and rate of adverse drug reactions (ADR). RESULTS: Sixteen RCTs involving 1,334 patients were identified. Compared with the atropine- or penehyclidine-alone groups, atropine combined with penehyclidine significantly increased the cure rate (penehyclidine+atropine vs. atropine, 0.97 vs. 0.86, RR 1.13, 95% CI [1.07-1.19]; penehyclidine+atropine vs. penehyclidine, 0.93 vs. 0.80, RR 1.08, 95% CI [1.01-1.15]) and reduced the mortality rate (penehyclidine+atropine vs. atropine, 0.015 vs. 0.11, RR 0.17, 95% CI [0.06-0.49]; penehyclidine+atropine vs. penehyclidine, 0.13 vs. 0.08, RR 0.23, 95% CI [0.04-1.28]). Atropine combined with penehyclidine in OP patients also helped reduce the time to atropinization and AchE recovery, the rate of IMS and the rate of ADR. Compared with a single dose of atropine, a single dose of penehyclidine also significantly elevated the cure rate, reduced times to atropinization, AchE recovery, and rate of IMS. CONCLUSION: Atropine combined with penehyclidine benefits OP patients by enhancing the cure rate, mortality rate, time to atropinization, AchE recovery, IMS rate, total ADR and duration of hospitalization. Penehyclidine combined with atropine is likely a better initial therapy for OP patients than atropine alone.

17.
Angew Chem Int Ed Engl ; 59(12): 4814-4821, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944516

RESUMO

The electrochemical CO2 reduction reaction (CO2 RR) to give C1 (formate and CO) products is one of the most techno-economically achievable strategies for alleviating CO2 emissions. Now, it is demonstrated that the SnOx shell in Sn2.7 Cu catalyst with a hierarchical Sn-Cu core can be reconstructed in situ under cathodic potentials of CO2 RR. The resulting Sn2.7 Cu catalyst achieves a high current density of 406.7±14.4 mA cm-2 with C1 Faradaic efficiency of 98.0±0.9 % at -0.70 V vs. RHE, and remains stable at 243.1±19.2 mA cm-2 with a C1 Faradaic efficiency of 99.0±0.5 % for 40 h at -0.55 V vs. RHE. DFT calculations indicate that the reconstructed Sn/SnOx interface facilitates formic acid production by optimizing binding of the reaction intermediate HCOO* while promotes Faradaic efficiency of C1 products by suppressing the competitive hydrogen evolution reaction, resulting in high Faradaic efficiency, current density, and stability of CO2 RR at low overpotentials.

18.
Adv Mater ; 32(7): e1906513, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31943380

RESUMO

Ferroelectric materials with spontaneous polarization-induced internal electric fields have drawn increasing attention in solar fuel production due to the intrinsic polarized structure. However, the origination of charge separation in these materials at the nano/microlevel is ambiguous owing to the complexity of the multielectric fields. Besides, the observed charge separation ability is far from theoretical expectation. Herein, by spatially resolved surface photovoltage spectroscopy, it is clearly demonstrated that the depolarization field in single-domain ferroelectric PbTiO3 (PTO) nanoplates is the main driving force for charge separation and it can effectively drive photogenerated electrons and holes to the positive and negative polarization facets, respectively. Moreover, the charge separation ability of PTO nanoplates increases with increasing particle size along the polarization direction, due to the increasing potential difference between the opposite polarization facets. Furthermore, this driving force for charge separation directly contributes to the enhancement of the photocatalytic hydrogen evolution reaction activity in ferroelectrics. Finally, it is proved that the screening field compensates part of the depolarization field and can be diminished by adding a dielectric layer on the ferroelectric surface. These findings demonstrate the importance of increasing the depolarization field and decreasing the screening field for efficient charge separation in ferroelectric semiconductor photocatalysts.

19.
Diagnostics (Basel) ; 10(1)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936481

RESUMO

Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications of diabetes. It has become an essential public health crisis, especially for care in the home. Synchronized electrocardiogram (ECG) and photoplethysmography (PPG) signals were obtained from healthy non-diabetic (n = 37) and diabetic (n = 85) subjects without peripheral neuropathy, recruited from the diabetic outpatient clinic. The conventional parameters, including low-/high-frequency power ratio (LHR), small-scale multiscale entropy index (MEISS), large-scale multiscale entropy index (MEILS), electrocardiogram-based pulse wave velocity (PWVmean), and percussion entropy index (PEI), were computed as baseline and were then followed for six years after the initial PEI measurement. Three new diabetic subgroups with different PEI values were identified for the goodness-of-fit test and Cox proportional Hazards model for relative risks analysis. Finally, Cox regression analysis showed that the PEI value was significantly and independently associated with the risk of developing DPN after adjustment for some traditional risk factors for diabetes (relative risks = 4.77, 95% confidence interval = 1.87 to 6.31, p = 0.015). These findings suggest that the PEI is an important risk parameter for new-onset DPN as a result of a chronic complication of diabetes and, thus, a smaller PEI value can provide valid information that may help identify type 2 diabetic patients at a greater risk of future DPN.

20.
Adv Mater ; 32(6): e1906193, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894628

RESUMO

Reversible exsolution and dissolution of metal nanoparticles in perovskite has been investigated as an efficient strategy to improve CO2 electrolysis performance. However, fundamental understanding with regard to the reversible exsolution and dissolution of metal nanoparticles in perovskite is still scarce. Herein, in situ exsolution and dissolution of CoFe alloy nanoparticles in Co-doped Sr2 Fe1.5 Mo0.5 O6-δ (SFMC) revealed by in situ X-ray diffraction, scanning transmission electron microscopy, environmental scanning electron microscopy, and density functional theory calculations are reported. Under a reducing atmosphere, facile exsolution of Co promotes reduction of the Fe cation to generate CoFe alloy nanoparticles in SFMC, accompanied by structure transformation from double perovskite to layered perovskite at 800 °C. Under an oxidizing atmosphere, spherical CoFe alloy nanoparticles are first oxidized to flat CoFeOx nanosheets, and then dissolved into the bulk with structure evolution from layered perovskite back to double perovskite. Electrochemically, CO2 electrolysis performance can be retrieved during 12 redox cycles due to the regenerative ability of the CoFe alloy nanoparticles. The anchoring of the CoFe alloy nanoparticles in SFMC perovskite via reduction shows enhanced CO2 electrolysis performance and stability compared with the parent SFMC perovskite.

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