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1.
Methods Mol Biol ; 2196: 117-141, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32889717

RESUMO

The successful assembly of nucleosomes following DNA replication is critically important for both the inheritance of epigenetic information and the maintenance of genome integrity. This process, termed DNA replication-coupled (RC) nucleosome assembly, requires that DNA replication and nucleosome assembly function in a highly coordinated fashion to transmit both genetic and epigenetic information. In this chapter, we describe a genome-wide method for measuring nucleosome occupancy patterns on nascent strands, which we have termed Replication-Intermediate Nucleosome Mapping (ReIN-Map), to monitor the RC nucleosome assembly level genome-wide in vivo. This method takes advantage of next-generation sequencing and in vivo labeling of newly synthesized DNA using a thymidine analogue, 5-bromo-2'-deoxyuridine (BrdU), and involves parallel analyses of the nucleosome formation using micrococcal nuclease (MNase) digestion of chromatin (MNase-seq) and of the newly synthesized DNA levels using sonication shearing of chromatin s (Sonication-seq). Replicated chromatin was enriched by immunoprecipitation using antibodies against BrdU (BrdU-IP), which is incorporated into DNA during DNA synthesis; the DNA is then subjected to strand-specific sequencing.

2.
Environ Sci Technol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030897

RESUMO

Perfluorooctanoic acid (PFOA) is bioaccumulative in crops. PFOA bioaccumulation potential varies largely among crop varieties. Root exudates are found to be associated with such variations. Concentrations of low-molecular-weight organic acids (LMWOAs) in root exudates from a PFOA-high-accumulation lettuce variety are observed significantly higher than those from PFOA-low-accumulation lettuce variety (p < 0.05). Root exudates and their LMWOAs components exert great influences on the linear sorption-desorption isotherms of PFOA in soils, thus activating PFOA and enhancing its bioavailability. Among root exudate components, oxalic acid is identified to play a key role in activating PFOA uptake, with >80% attribution. Oxalic acid at rhizospheric concentrations (0.02-0.5 mM) can effectively inhibit PFOA sorption to soils by decreasing hydrophobic force, electrostatic attraction, ligand exchange, and cation-bridge effect. Oxalic acid enhances dissolution of metallic ions, iron/aluminum oxides, and organic matters from soils and forms oxalate-metal complexes, based on nuclear magnetic resonance spectra, ultraviolet spectra, and analyses of metal ions, iron/aluminum organometallic complexes, and dissolved organic carbon. The findings not only reveal the activation process of PFOA in soils by root exudates, particularly oxalic acid at rhizospheric concentrations, but also give an insight into the mechanism of enhancing PFOA accumulation in lettuce varieties.

3.
Int J Biol Macromol ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33031850

RESUMO

As one of the most promising biopolymers for a variety of potential applications, chitosan has attracted much attention because of its unique biological, chemical, and physical properties. The functionalization of chitosan has been adopted to synthesize novel chitosan derivatives with improved water-solubility and excellent biological activities. In this paper, chitosan was functionalized with a triphenylphosphonium group by means of the copper (I) catalyzed azide-alkyne "click" reaction and has been investigated as potential polymer for agricultural antifungal biomaterial. The influence of chemical modification on the structural characteristics and water-solubility of chitosan was investigated by FTIR spectroscopy, 1H NMR spectroscopy, elemental analysis, and UV-vis spectrum. Furthermore, the antifungal property of target chitosan derivative against four plant threatening fungal pathogens was evaluated and in vitro investigation demonstrated that triphenylphosphonium salt incorporated chitosan backbone had excellent antifungal property compared with chitosan and intermediate chitosan derivative. Notably, target chitosan derivative displayed relatively strongest antifungal effect with over 80% inhibitory index against Botrytis cinerea at 1.0 mg/mL. The results of a detailed antifungal study indicated that cationic chitosan derivative bearing 1,2,3-triazole and triphenylphosphonium moieties provided a promising platform for preparation of novel cationic antifungal biomaterials in the field of agriculture.

4.
Value Health ; 23(10): 1307-1315, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33032774

RESUMO

OBJECTIVES: Hospital readmission is a main cost driver for healthcare systems, but existing works often had poor or moderate predictive results. Although the available information differs in different studies, improving prediction is different from the search for important explanatory variables. With large sample size and abundant information, this study explores state-of-the-art machine-learning algorithms and shows their performance in prediction. METHODS: Using administrative data on 1 631 611 hospital stays from Quebec between 1995 and 2012, we predict the probability of 30-day readmission at hospital admission and discharge. We compare the performance between traditional logistic regression, logistic regression with penalization, and more recent machine-learning algorithms such as random forest, deep learning, and extreme gradient boosting. RESULTS: After a 10-fold cross-validation on the training set (80% of the data), machine learning produced very good results on a separate hold-out test set (20% of the data). The importance of explanatory variables is not the same for different algorithms. The area under receiver operating characteristic curve (AUC) reached above 0.79 at hospital admission and above 0.88 at hospital discharge. Diagnostic codes, which include many different categories, are among the most predictive variables. Logistic regression with penalization also produced good results, but a standard logistic regression failed without penalization. The good results are confirmed by calibration curves. CONCLUSION: Although the identification of those at highest risk of readmission is just 1 step to preventing hospital readmissions, 30-day readmission is highly predictable with machine learning.

5.
Chemistry ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034925

RESUMO

Over the past decades, N -heterocyclic carbene (NHC) organocatalysis has undergone flourish development on the basis of closed-shell reaction paths. By contrast, the emerging area of single electron transfer (SET) reactions enabled by NHC catalysis still remain underdeveloped, but offer plenty of opportunities to develop new catalytic modes and useful synthetic methods. A number of interesting transformations were triggered by the SET process from the electron-rich Breslow intermediates to various single-electron acceptors. In additions, recent studies released that the Breslow radical cations could also be generated by single-electron reduction of the electron-deficient acyl azolium intermediates. These discoveries open a new avenue for NHC organocatalysis to harness radical reactions. The present review will focus on the exciting advancements in the dynamic area of radical NHC organocatalysis.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33022658

RESUMO

The structural evolution of Er55Al25Co20 metallic glasses (MGs) at high pressure was studied through X-ray diffraction with synchrotron radiation. The relative volume VP/V0, pair distribution function g(r), and relative resistance as functions of pressure were discussed. A reversible polyamorphic transition with an obvious hysteresis was detected in the Er55Al25Co20 MGs. The irreversible annihilation of free volume and voids led to a densification of the specimens. Electronic resistance measurements demonstrated that the transition was strongly correlated with the electronic structural evolution. The results provided a new insight into understanding the mechanism of polyamorphism in MGs.

7.
Urol Int ; : 1-6, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33022676

RESUMO

OBJECTIVE: The aim of this study was to estimate the clinical effects of allogeneic acellular dermal matrix (ADM) in the surgical therapy of anterior urethral stricture (AUS). METHODS: We retrospectively collected the clinical data of 49 patients with AUS who underwent urethral repair surgery with ADM in the Department of Urology of the Peking University People's Hospital, and in the First Affiliated Hospital of the People's Liberation Army, from September 2015 to January 2019. The changes in urine flow rate and conditions of urethral mucosal coverage were observed as well as complications and outcomes, and statistical analysis was performed. RESULTS: The average maximum urine flow rates at the 1st, 6th, and 12th month post-surgery were 16.3 ± 1.5, 15.0 ± 1.9, and 14.6 ± 2.1 mL/s, respectively. These values were significantly higher than the preoperative maximum urine flow rate, 1.3 ± 0.5 mL/s (p < 0.05). Cystoscopy was performed in 11 patients 12 months after surgery, with microscopic assessment revealing good urethral epithelial mucosal coverage. Only 2 patients developed infection 2-4 weeks after surgery, while 7 patients developed noninfective urethral restricture 6-10 months after surgery and 1 patient developed urinary fistula 5 months after surgery. All of these statuses improved after receiving appropriate treatment. CONCLUSIONS: Use of ADM represents a new option for the surgical management of AUS repair and reconstruction, with positive clinical effects. In addition, it has the advantages of convenient for operation procedures and access, with no need for additional sampling surgery.

8.
Sensors (Basel) ; 20(19)2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023183

RESUMO

Inter-satellite laser communication (Is-OWC) is one of the main space optical communication technologies currently studied in various countries. In recent years, a kind of Is-OWC communication terminal without independent beacon light has appeared. Such terminals do not have a separate beacon laser with a large divergence angle, but use a narrower communication beam to complete space capture and tracking. Therefore, the energy of the light beam divided by the acquisition, tracking, and aiming (ATP) system is greatly reduced. How to perform high-precision spot position detection under extremely low signal-to-noise ratio (SNR) is a problem that must be faced. Aiming to resolve this problem, this article proposes to use a cosine signal to modulate the intensity of the signal light, so as to convert the problem of detecting a weak light signal into the problem of detecting a line spectrum signal. The authors used the time reversal convolution (TRC) algorithm with a window function to suppress noise and enhance the spectrum line, so as to accurately detect the amplitudes of the weak photocurrents. Finally, by calculating the ratio of the photocurrent amplitude values, the precise spot position is obtained. In the experiment, when the output SNR of the four-quadrant detector (QD) is as low as -17.86 dB, the proposed method can still detect the spot position and the absolute error is limited within 0.0238 mrad.

9.
Curr Genet ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025160

RESUMO

Replication-coupled (RC) nucleosome assembly is an essential process in eukaryotic cells to maintain chromatin structure during DNA replication. The deposition of newly-synthesized H3/H4 histones during DNA replication is facilitated by specialized histone chaperones. CAF-1 is an important histone chaperone complex and its main subunit, Cac1p, contains a PIP and WHD domain for interaction with PCNA and the DNA, respectively. While Cac1p subunit was extensively studied in different systems much less is known regarding the importance of the PIP and WHD domains in replication fork progression and genome stability. By exploiting a time-lapse microscopy system for monitoring DNA replication in individual live cells, we examined how mutations in these Cac1p domains affect replication fork progression and post-replication characteristics. Our experiments revealed that mutations in the Cac1p WHD domain, which abolished the CAF-1-DNA interaction, slows down replication fork progression. In contrast, mutations in Cac1p PIP domain, abolishing Cac1p-PCNA interaction, lead to extended late-S/Anaphase duration, elevated number of RPA foci and increased spontaneous mutation rate. Our research shows that Cac1p WHD and PIP domains have distinct roles in high replisome progression and maintaining genome stability during cell cycle progression.

10.
Theranostics ; 10(25): 11754-11774, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052245

RESUMO

Rationale: The crosstalk between cardiac microvascular endothelial cells (CMECs) and cardiomyocytes (CMs) has emerged as a key component in the development of, and protection against, cardiac diseases. For example, activation of endothelial nitric oxide synthase (eNOS) in CMECs, by therapeutic strategies such as ischemic preconditioning, plays a critical role in the protection against myocardial ischemia/reperfusion (I/R) injury. However, much less is known about the signals produced by CMs that are able to regulate CMEC biology. Here we uncovered one such mechanism using Tongxinluo (TXL), a traditional Chinese medicine, that alleviates myocardial ischemia/reperfusion (I/R) injury by activating CMEC eNOS. The aim of our study is to identify the signals produced by CMs that can regulate CMEC biology during I/R. Methods: Ex vivo, in vivo, and in vitro settings of ischemia-reperfusion were used in our study, with the protective signaling pathways activated in CMECs identified using genetic inhibition (p70s6k1 siRNA, miR-145-5p mimics, etc.), chemical inhibitors (the eNOS inhibitor, L-NNA, and the small extracellular vesicles (sEVs) inhibitor, GW4869) and Western blot analyses. TritonX-100 at a dose of 0.125% was utilized to inactivate the eNOS activity in endothelium to investigate the role of CMEC-derived eNOS in TXL-induced cardioprotection. Results: We found that while CMEC-derived eNOS activity was required for the cardioprotection of TXL, activation of eNOS in CMECs by TXL did not occur directly. Instead, eNOS activation in CMECs required a crosstalk between CMs and CMECs through the uptake of CM-derived sEVs. We further demonstrate that TXL induced CM-sEVs contain increased levels of Long Intergenic Non-Protein Coding RNA, Regulator Of Reprogramming (Linc-ROR). Upon uptake into CMECs, linc-ROR downregulates its target miR-145-5p leading to activation of the eNOS pathway by facilitating the expression of p70s6k1 in these cells. The activation of CMEC-derived eNOS works to increase survival in both the CMECs and the CMs themselves. Conclusions: These data uncover a mechanism by which the crosstalk between CMs and CMECs leads to the increased survival of the heart after I/R injury and point to a new therapeutic target for the blunting of myocardial I/R injury.

11.
Braz J Med Biol Res ; 53(11): e10068, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33053111

RESUMO

Diabetes mellitus (DM) has a high prevalence in patients with pancreatic cancer (PaC), but the prognostic value of DM in PaC remains controversial. Alterations of P-glycoprotein (P-gp) and cytochrome P450 3A4 (CYP3A4) contribute to multidrug resistance and intestinal metabolism in a variety of cancer types, which may be implicated in DM development. This study aimed to explore the potential prognostic value of P-gp and CYP3A4 in PaC patients in the context of DM through long-term follow-up. We retrospectively reviewed the medical records of patients with PaC admitted at The First People's Hospital of Changzhou, Jiangsu, China, from January 2011 to November 2019 and identified two cohorts of adult patients with PaC, including 24 with DM and 24 without DM (non-DM). The baseline clinical characteristics and outcomes were compared. Immunohistochemistry showed that protein expression of P-gp, but not CYP3A, in duodenum tissues was significantly upregulated in PaC patients with DM compared with those without DM. Kaplan-Meier analysis and log-rank test showed that the survival of patients with PaC and DM/high expression of P-gp was not significantly reduced compared with that of patients without DM/low expression of P-gp. These findings suggested that P-gp expression levels were different in the DM and non-DM groups of patients with PaC, but DM and duodenal P-gp levels were not associated with the long-term survival of patients with PaC. It appears that the presence of DM or P-gp expression levels may not serve as effective prognostic markers for PaC.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1440-1444, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067934

RESUMO

OBJECTIVE: To explore the efficacy and adverse reactions of decitabine combined with reduction FLAG regimen on the senile patients with high-risk AML. METHODS: 12 senile patients with high-risk AML received decitabine combined with reduced FLAG regimen (decitabine 20 mg/m2, intravenous drip, qd, d 1-5; fludarabine 30 mg/m2, intravenous drip lasts 30 min, qd, d 3-6; Ara-C 1 g/m2, intravenous drip, qd, d 3-6; and G-CSF 300 µg/d, subcu- taneous injection, d 2 to neutrophils reached the lowest return to>1.0×109/L) in our study. The efficacy and adverse reactions of this regimen were analyzed. RESULTS: 9 patients achieved complete remission(CR) after one course of decitabine combined with reduced FLAG regimen, 2 patients achieved partial remission (PR) and 1 patient reached a stable disease (SD). The overall response rate was 92%. The median follow-up period was 7.4 months ranged from 3 to 12 months. The median survival time for all patients was 6.4 months. The main treatment-related toxicities were myelosuppression and infection due to neutropenia. Severe non-hematologic toxicities were not observed in these patients, and there was no treatment-related mortality. CONCLUSION: Decitabine combined with reduced FLAG regimen has a definite clinical efficacy in the treatment of senile patients with high-risk AML. This regimen, as induction remission regimen, can effectively improve the CR rate and reduce the adverse reactions. Therefore, it may be used as one of the preferred induction remission regimen to treat the senile patients with high-risk AML.

13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1746-1749, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067984

RESUMO

AbstractObjective: To evaluate the diagnostic value of serum PCT, CRP and SAA for bloodstream infection(BSI) in patients with hematopathy. METHODS: Sixty hematopathy patients with bloodstream infection from July 2016 to June 2018 were selected and enroued in bloodstream infection group. Sixty-five patients with negative blood culture during the same period were selected and enrolled in non-bloodstream infection group. The ROC curves were drawn and used to eualuate the diagnostic value of above montioned indexes. RESULTS: The levels of PCT, CRP and SAA in the bloodstream infection group were higher than those in the non-bloodstream infection group (P<0.05). ROC curve showed that AUC values of PCT, CRP, SAA and the combined test detection were 0.868, 0.746, 0.678 and 0.900, respectively, there was no significant difference in AUC between combined test and PCT test (P>0.05). AUC of combined test and PCT test were higher than those of CRP and SAA test, and the difference was statistically significant (P<0.05), but there was no significant difference in AUC between CRP and SAA (P>0.05). The optimal PCT detection threshold was 0.49 ng/ml, the sensitivity and specificity were 75.0% and 83.1%, respectively. The optimal critical value for CRP detection was 15.76 mg/L, the sensitivity and specificity were 60.0% and 80.0% respectively. The optimal SAA detection threshold was 35.66 mg/L, the sensitivity and specificity were 81.7% and 53.8%, respectively. CONCLUSION: PCT, CRP and SAA detection have good diagnostic value for blood stream infection in patients with hematopathy. The diagnostic value of PCT is better than CRP and SAA, and there is no significant difference in diagnostic value between combined test and PCT test.

14.
ISA Trans ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33069372

RESUMO

In bearings defect diagnosis applications, information fusion has been widely used to improve identification accuracy for different types of faults, which may lead to high-dimensionality and information redundancy of the data and thus degenerate the classification performance. Therefore, it is a major challenge for machinery fault diagnosis to extract optimal features from high-dimensional and redundant data for classification. In addition, in order to guarantee the performance of fault diagnosis, conventional supervised methods usually require a large amount of labeled data available for learning. However, it is extremely difficult, costly and time-consuming to collect faulty labeled samples with class information, especially for expensive and critical machines, which often results in only a few labeled data available with a large amount of unlabeled data redundant. In this paper, we propose a novel bearing defect diagnosis model based on semi-supervised kernel local Fisher Discriminant Analysis (SSKLFDA) using pseudo labels, which can effectively extract optimal features for classification and simultaneously utilize unlabeled data for regularizing the supervised dimensionality reduction. The proposed SSKLFDA first adopts Density Peak Clustering technique to generate pseudo cluster labels for the labeled and unlabeled data and then regularizes the between-class scatter and within-class scatter according to two corresponding regularization strategies associated with the generated pseudo cluster labels. This regularization can further improve the discriminant performance of the extracted features and also make it suitable for the cases with the multimodality and noises. In order to accommodate for non-linear feature extraction, the kernel version of the proposed method is also provided with the introduction of kernel trick. The experimental results under different feature dimensions, numbers of labeled data, and subsequent classifiers scenarios demonstrate that the proposed SSKLFDA based bearings fault diagnosis model achieves higher classification performance than other existing dimensionality reduction methods-based models.

15.
J Exp Psychol Gen ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001683

RESUMO

Response errors often cause individuals to slow down their subsequent reactions (posterror slowing [PES]). Despite intensive investigations on PES, the adaptive nature of PES remains unresolved. Here, we systematically examined this issue by manipulating response-stimulus intervals (RSIs) and examining their influence on behaviors and neural dynamics of PES. Behavioral and electrophysiological (EEG) measures were recorded while male and female human participants performed a four-choice flanker task as RSIs were manipulated. Behaviorally, PES showed maladaptive features at short RSIs but some adaptive features at long RSIs. EEG results indicated that RSIs did not affect basic error-related processing, indexed by the same pattern in the contrasts between flanker errors and correct responses on the error-related negativity (ERN), error positivity (Pe), or theta band, no matter at short or long RSIs. However, RSIs significantly influenced postflanker error attentional adjustment, motor inhibition, and sensory sensitivity. At short RSIs, compared with postcorrect trials, postflanker error trials elicited larger beta band power and smaller P1 amplitude but did not affect alpha band power, suggesting that motor processing was inhibited, and subsequent sensory processing was impaired, but no attentional adjustment occurred. By contrast, at long RSIs, postflanker error trials led to smaller alpha and beta band power but did not affect P1 amplitude, indicating that attentional adjustment but not motor inhibition occurred, and sensory processing was not impaired. Together with behavioral results, the current study demonstrated that PES was adaptive at long RSIs but maladaptive at short RSIs. We further discuss the role of central resources in the adaptability of PES. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

16.
Mol Ther ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038325

RESUMO

Tissue stem cell senescence leads to stem cell exhaustion, which results in tissue homeostasis imbalance and a decline in regeneration capacity. However, whether neural stem cell (NSC) senescence occurs and causes neurogenesis reduction during aging is unknown. In this study, mice at different ages were used to detect age-related hippocampal NSC (H-NSC) senescence, as well as the function and mechanism of embryonic stem cell-derived small extracellular vesicles (ESC-sEVs) in rejuvenating H-NSC senescence. We found a progressive cognitive impairment, as well as age-related H-NSC senescence, in mice. ESC-sEV treatment significantly alleviated H-NSC senescence, recovered compromised self-renewal and neurogenesis capacities, and reversed cognitive impairment. Transcriptome analysis revealed that myelin transcription factor 1 (MYT1) is downregulated in senescent H-NSCs but upregulated by ESC-sEV treatment. In addition, knockdown of MYT1 in young H-NSCs accelerated age-related phenotypes and impaired proliferation and differentiation capacities. Mechanistically, ESC-sEVs rejuvenated senescent H-NSCs partly by transferring SMAD family members 4 (SMAD4) and 5 (SMAD5) to activate MYT1, which downregulated egl-9 family hypoxia inducible factor 3 (Egln3), followed by activation of hypoxia inducible factor 2 subunit α (HIF-2α), nicotinamide phosphoribosyl transferase (NAMPT), and sirtuin 1 (Sirt1) successively. Taken together, our results indicated that H-NSC senescence caused cellular exhaustion, neurogenesis reduction, and cognitive impairment during aging, which can be reversed by ESC-sEVs. Thus, ESC-sEVs may be promising therapeutic candidates for age-related diseases.

17.
Cardiovasc Diabetol ; 19(1): 161, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998742

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) increases the risks of heart failure and mortality in patients with hypertension, however the underlying mechanism is unclear. This study aims to investigate the impact of coexisting T2DM on left ventricular (LV) deformation and myocardial perfusion in hypertensive individuals. MATERIALS AND METHODS: Seventy hypertensive patients without T2DM [HTN(T2DM-)], forty patients with T2DM [HTN(T2DM+)] and 37 age- and sex-matched controls underwent cardiac magnetic resonance examination. Left ventricular (LV) myocardial strains, including global radial (GRPS), circumferential (GCPS) and longitudinal peak strain (GLPS), and resting myocardial perfusion indices, including upslope, time to maximum signal intensity (TTM), and max signal intensity (MaxSI), were measured and compared among groups by analysis of covariance after adjusting for age, sex, body mass index (BMI) and heart rate followed by Bonferroni's post hoc test. Backwards stepwise multivariable linear regression analyses were performed to determine the effects of T2DM on LV strains and myocardial perfusion indices in patients with hypertension. RESULTS: Both GRPS and GLPS deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM+) group; GCPS in HTN(T2DM+) group was lower than those in both HTN(T2DM-) and control groups. Compared with controls, HTN(T2DM-) group showed higher myocardial perfusion, and HTN(T2DM+) group exhibited lower perfusion than HTN(T2DM-) group and controls. Multiple regression analyses considering covariates of systolic blood pressure, age, sex, BMI, heart rate, smoking, indexed LV mass and eGFR demonstrated that T2DM was independently associated with LV strains (GRPS: p = 0.002, model R2= 0.383; GCPS: p < 0.001, model R2= 0.472; and GLPS: p = 0.002, model R2= 0.424, respectively) and perfusion indices (upslope: p < 0.001, model R2= 0.293; TTM: p < 0.001, model R2= 0.299; and MaxSI: p < 0.001, model R2= 0.268, respectively) in hypertension. When both T2DM and perfusion indices were included in the regression analyses, both T2DM and TTM were independently associated with GRPS (p = 0.044 and 0.017, model R2= 0.390) and GCPS (p = 0.002 and 0.001, model R2= 0.424), and T2DM but not perfusion indices was independently associated with GLPS (p = 0.002, model R2= 0.424). CONCLUSION: In patients with hypertension, T2DM had an additive deleterious effect on subclinical LV systolic dysfunction and myocardial perfusion, and impaired myocardial perfusion by coexisting T2DM was associated with deteriorated LV systolic dysfunction.

18.
J Colloid Interface Sci ; 583: 234-242, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-33002695

RESUMO

Heating treatment is widely used in the preparation of metallic materials with controlled phase behavior and mechanical properties. However, for the soft materials assembled by short peptides, especially simple dipeptides, the detailed influences of heating treatment on the structures and functions of the materials remain largely unexplored. Here we showed that by thermal annealing or quenching of aromatic peptide solutions under kinetic control, we are able to control the self-assembly of peptide into materials with distinct phase behavior and macroscopic properties. The thermal annealing of the heated peptide solutions will lead to the formation of large nanobelts or bundles in solution, and no gels will be formed. However, by quenching the heated peptide solution, a self-supporting hydrogel will be formed quickly. Structure analysis revealed that the peptides preferred to self-assembled into much thinner and flexible nanohelices during quenching treatment. Moreover, the stability of the gels further increased with the repeated heating and quenching cycling of the peptide solutions. The results demonstrated that the heat treatment can be used to control the structure and function of self-assembled materials in a way similar to that of the conventional metallic or alloy materials.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 118995, 2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-33032118

RESUMO

KTaO3 and Cu2+ doped KTaO3 were prepared by a solvothermal process. The measurements of XRD, FTIR, XPS, SEM, BET specific surface area, DRS, photoluminescence, photocurrent and electrochemical impedance spectroscopy measurements were carried out to investigate their physical and chemical properties. Especially, the photocatalytic activities of them were revealed by the photocatalysis of MB with irradiation of light in UV-Vis region. The measurements indicate that the Cu2+ doping does not obviously influence the phase and microstructure of KTaO3, but highly changes the optical and electrochemical properties. Cu2+ doped KTaO3 shows higher photocatalytic activity than KTaO3 in the degradation of methylene blue with irradiation of light in UV-Vis region, which results from the enhanced light absorbance, more efficient transfers and separation of photogenerated charge carriers.

20.
Sci Total Environ ; 755(Pt 1): 142505, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33038839

RESUMO

Chlorpyrifos is an important organophosphorus insecticide. It is highly toxic to mammals and can pollute the environment. Cupriavidus nantongensis X1T can efficiently degrade chlorpyrifos. Immobilization technology can also improve the viability, stability and catalytic ability of bacteria. In this study, strain X1T was, therefore, captured on various composite immobilized carriers, sodium alginate (SA), diatomite (KLG), chitosan (CTS) and polyvinyl alcohol (PVA). The four types of immobilized beads (SA, SA + KLG, SA + CTS and SA + PVA) could form a slice and honeycomb structure to capture strain X1T. The results showed that SA + CTS (SC) was an optimal material combination for the immobilization of strain X1T to degrade chlorpyrifos. Compared with SA-X1T, after adding CTS, the specific surface area and adsorption capacity for chlorpyrifos were increased 3.4 and 1.7 fold, respectively. SC-X1T could degrade 96.6% of chlorpyrifos at 20 mg/L within 24 h and the degradation rate constant was 4.8 fold greater than immobilized strain LLBD2, a well-studied chlorpyrifos-degrading strain. The immobilized beads SC-X1T also showed a more stable and greater degradation ability than X1T free cells for chlorpyrifos in industrial wastewater. The synergy of adsorption and degradation of immobilized strain X1T is suitable for in-situ remediation of chlorpyrifos contaminated environment.

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