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1.
Lab Invest ; 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230646

RESUMO

In the myocardial infarction microenvironment, the effect of macrophages on the function of bone marrow mesenchymal stem cells (BMSCs) is unclear. In this study, we investigated the role of hypoxia/serum deprivation (H/SD)-induced M1-type macrophage-derived exosomes on BMSC viability, migration, and apoptosis. We found that H/SD reduced BMSC viability and migration, increased BMSC apoptosis, and induced macrophage polarization toward the M1 phenotype. BMSCs were cultured by the supernatant of H/SD-induced THP-1 cells (M1-type macrophages) with or without exosome inhibitor treatment. The results show that BMSC apoptosis is increased in the H/SD-induced THP-1 cell supernatant group and is decreased by GM4869 treatment, indicating that M1-type macrophages induce BMSC apoptosis through exosomes. In addition, we confirm that miR-222 plays an important role in promoting BMSC apoptosis by targeting B-cell lymphoma (Bcl)-2. M1-type macrophage-derived exosomes significantly decrease BMSC viability and migration and increase BMSC apoptosis, and these effects are partly abolished by a miR-222 inhibitor. Our findings suggest that under H/SD conditions, exosomes derived from M1-type macrophages can induce BMSC apoptosis by delivering miR-222 to BMSCs.

2.
J Vet Med Sci ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234054

RESUMO

The Cap of porcine circovirus type 2 (PCV2) can be assembled into virus like particles (VLPs) in vitro that have multiple loops located on the particle surface. This would make it a good vehicle for displaying exogenous proteins or epitopes. We derived two epitopes, epitope B (EpB, S37HIQLIYNL45) and epitope 7 (Ep7, Q196WGRL200) from Gp5 of the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV). We replaced the core region of Loop CD (L75PPGGGSN82) and the carboxyl terminus (K222DPPL226) of PCV2 Cap, respectively, to construct a bi-epitope chimeric PCV2 Cap. Its immunogenicity and protective effects were evaluated as one PRRSV subunit vaccine. The chimeric PCV2 Cap was soluble, efficiently expressed in an Escherichia coli expression system, and could be self-assembled into chimeric virus like particles (cVLPs) with a diameter of 12-15 nm. Western blotting confirmed that the cVLPs could be specifically recognized by anti-PCV2, anti-EpB and anti-Ep7 antibodies. The cVLPs vaccine could alleviate the clinical symptoms and reduce the viral loads after HP-PRRSV challenge in 100-120 days old pigs. These data suggest that the cVLPs vaccine could provide pigs with partial protection against homologous PRRSV strains, and it provides a new design for additional PRRSV subunit vaccines.

3.
J Clin Invest ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34255748

RESUMO

PFKP (phosphofructokinase, platelet), the major isoform of PFK1 expressed in T cell acute lymphoblastic leukemia (T-ALL), is predominantly expressed in the cytoplasm to carry out its glycolytic function. Our study showed PFKP was a cyto-nuclear shuttling protein with functional nuclear export and nuclear localization sequences. Cyclin D3/CDK6 facilitated PFKP nuclear translocation by dimerization and by exposing the NLS of PFKP to induce the interaction between PFKP and importin 9. Nuclear PFKP stimulated the expression of C-X-C chemokine receptor type 4 (CXCR4), a chemokine receptor regulating leukemia homing/infiltration, to promote T-ALL cell invasion, which depended on the activity of c-Myc. In vivo experiments showed that nuclear PFKP promoted leukemia homing/infiltration into the bone marrow, spleen and liver, which could be blocked with CXCR4 antagonists. Immunohistochemistry staining of tissues from a clinically well-annotated cohort of T cell lymphoma/leukemia patients showed nuclear PFKP localization only in invasive cancers, but not in non-malignant T lymph node or reactive hyperplasia. The presence of nuclear PFKP in these specimens correlated with poor survival in patients with T cell malignancy, suggesting the potential utility of nuclear PFKP as a diagnostic marker.

4.
ACS Infect Dis ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34254783

RESUMO

Cerebral malaria (CM) is caused by Plasmodium falciparum, resulting in severe sequelae; one of its pathogenic factors is the low bioavailability of nitric oxide (NO). Our previous study suggested that the combination of artesunate (AS) and tetramethylpyrazine (TMP) exerts an adjuvant therapeutic effect on the symptoms of experimental CM (ECM) and that NO regulation plays an important role. In the present study, we further verified the effects of AS+TMP on cerebral blood flow (CBF) and detected NO-related indicators. We focused on the role of NO through S-nitrosoproteome based on previous proteomics data and explored the mechanism of AS+TMP for improving pathological ECM symptoms. We observed that AS+TMP reduces adhesion, increases CBF, and regulates NO synthase (NOS) activity, thereby regulating the level of S-nitrosothiols, such as metabolism-related or neuro-associated receptors, for improving ECM symptoms. These results demonstrated that AS+TMP could be an effective strategy in adjuvant therapy of CM.

5.
Physiol Plant ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237150

RESUMO

Paeonia is recognized globally due to its ornamental value. However, the mechanisms behind the formation of distinct levels of lignification in Paeonia stems remain largely unknown. In this study, we selected three representative Paeonia species, namely P. ostii (shrub), P. lactiflora (herb), and P. × 'Hexie' (semi-shrub), to evaluate and contrast their respective anatomical structure, phytochemical composition and transcriptomic profile. Our results showed that the degree of lignin deposition on the cell wall, along with the total amount of lignin and its monomers (especially G-lignin) were higher in P. ostii stems compared to the other two species at almost all development stages except 80 days after flowering. Furthermore, we estimated a total number of unigenes of 60,238 in P. ostii, 43,563 in P. × 'Hexie', and 40,212 in P. lactiflora from stem transcriptome. We then built a co-expression network of 25 transcription factors and 21 enzyme genes involved in lignin biosynthesis and identified nine key candidate genes. The expression patterns of these genes were positively correlated with the transcription levels of PAL, C4H, 4CL2, CCR, and COMT, as well as lignin content. Moreover, the highest relative expression levels of CCR, 4CL2, and C4H were found in P. ostii. This study provides an explanation for the observed differences in lignification between woody and herbaceous Paeonia stems, and constitutes a novel reference for molecular studies of stem-specific lignification process and lignin biosynthesis that can impact the ornamental industry.

6.
Nat Commun ; 12(1): 4063, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210975

RESUMO

Identification of novel functional domains and characterization of detailed regulatory mechanisms in cancer-driving genes is critical for advanced cancer therapy. To date, CRISPR gene editing has primarily been applied to defining the role of individual genes. Recently, high-density mutagenesis via CRISPR tiling of gene-coding exons has been demonstrated to identify functional regions in genes. Furthermore, breakthroughs in combining CRISPR library screens with single-cell droplet RNA sequencing (sc-RNAseq) platforms have revealed the capacity to monitor gene expression changes upon genetic perturbations at single-cell resolution. Here, we present "sc-Tiling," which integrates a CRISPR gene-tiling screen with single-cell transcriptomic and protein structural analyses. Distinct from other reported single-cell CRISPR screens focused on observing gene function and gene-to-gene/enhancer-to-gene regulation, sc-Tiling enables the capacity to identify regulatory mechanisms within a gene-coding region that dictate gene activity and therapeutic response.

7.
Int J Cancer ; 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34287840

RESUMO

Although cancer is highly heterogeneous, all metastatic cancer is considered American Joint Committee on Cancer (AJCC) Stage IV disease. Internal validation of nationally representative patient data from the National Cancer Database (n = 461 357; 2010-2013), and external validation using the Surveillance, Epidemiology, and End Results database (n = 106 595; 2014-2015) were assessed using the concordance index. Bayesian information criterion (BIC) and sample-size adjusted BIC identified distinct clusters. Kappa coefficients assessed external cluster validation. A Cox proportional hazards model with identified latent class as the stratification variable was used for overall survival. Latent class analysis identified five metastatic phenotypes with differences in overall survival (P < 0.0001): (Stage IVA) nearly-exclusive bone-only metastases (n = 59 049, 12.8%; median survival 12.7 months; common in lung, breast, and prostate cancers); (IVB) predominant lung metastases (n = 62 491, 13.5%; 11.4 months; common in breast, stomach, kidney, ovary, uterus, thyroid, cervix, and soft tissue cancers); (IVC) predominant liver/lung metastases (n = 130 014, 28.2%; 7.0 months; common in colorectum, pancreatic, lung, esophagus, and stomach cancers); (IVD) bone/liver/lung metastases predominant over brain (n = 61 004, 13.2%; 5.9 months; common in lung and breast cancers); and (IVE) brain/lung metastases predominant over bone/liver (n = 148 799, 32.3%; 5.7 months; lung cancer and melanoma). Long-term survivors were identified, particularly in Stages IVA-B. A pan-cancer nomogram model to predict survival (STARS: Site, Tumor, Age, Race, Sex) was created, validated, and provides 13% better prognostication than AJCC: 1-month concordance-index of 0.67 (95% CI 0.66-0.67) vs 0.61 (95% CI 0.60-0.61). STARS is simple, uses easily-accessible variables, better prognosticates survival outcomes, and provides a platform to develop novel metastasis-directed clinical trials. This article is protected by copyright. All rights reserved.

8.
Chin J Acad Radiol ; : 1-9, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: covidwho-1286228

RESUMO

Background: Coronary artery calcification (CAC) is an independent risk factor of major adverse cardiovascular events; however, the impact of CAC on in-hospital death and adverse clinical outcomes in patients with coronavirus disease 2019 (COVID-19) remains unclear. Objective: To explore the association between CAC and in-hospital mortality and adverse events in patients with COVID-19. Methods: This multicenter retrospective cohort study enrolled 2067 laboratory-confirmed COVID-19 patients with definitive clinical outcomes (death or discharge) admitted from 22 tertiary hospitals in China between January 3, 2020 and April 2, 2020. Demographic, clinical, laboratory results, chest CT findings, and CAC on admission were collected. The primary outcome was in-hospital death and the secondary outcome was composed of in-hospital death, admission to intensive care unit (ICU), and requiring mechanical ventilation. Multivariable Cox regression analysis and Kaplan-Meier plots were used to explore the association between CAC and in-hospital death and adverse clinical outcomes. Results: The mean age was 50 years (SD,16) and 1097 (53.1%) were male. A total of 177 patients showed high CAC level, and compared with patients with low CAC, these patients were older (mean age: 49 vs. 69 years, P < 0.001) and more likely to be male (52.0% vs. 65.0%, P = 0.001). Comorbidities, including cardiovascular disease (CVD) ([33.3%, 59/177] vs. [4.7%, 89/1890], P < 0.001), presented more often among patients with high CAC, compared with patients with low CAC. As for laboratory results, patients with high CAC had higher rates of increased D-dimer, LDH, as well as CK-MB (all P < 0.05). The mean CT severity score in high CAC group was also higher than low CAC group (12.6 vs. 11.1, P = 0.005). In multivariable Cox regression model, patients with high CAC were at a higher risk of in-hospital death (hazard ratio [HR], 1.731; 95% CI 1.010-2.971, P = 0.046) and adverse clinical outcomes (HR, 1.611; 95% CL 1.087-2.387, P = 0.018). Conclusion: High CAC is a risk factor associated with in-hospital death and adverse clinical outcomes in patients with confirmed COVID-19, which highlights the importance of calcium load testing for hospitalized COVID-19 patients and calls for attention to patients with high CAC. Supplementary Information: The online version contains supplementary material available at 10.1007/s42058-021-00072-4.

9.
Parasitol Res ; 2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34272998

RESUMO

Currently, conjugation of artemisinin-derived dimers, trimers, and tetramers is a viable strategy for developing new effective antimalarial candidates. Furthermore, nanotechnology is an effective means to achieve intravenous administration of hydrophobic drugs. In this paper, an ester-linked dihydroartemisinin trimer (DHA3) was synthesized and further prepared as self-assembled nanoparticles (DHA3NPs) by a one-step nanoprecipitation method. The pharmacokinetics and antimalarial pharmacodynamics of DHA3NPs were studied in rats and mice infected with Plasmodium yoelii BY265 (PyBY265). DHA3NPs had a regular spherical shape with a uniform size distribution of 140.27 ± 3.59 nm, entrapment efficiency (EE) of 99.63 ± 0.17%, and drug loading efficiency (DL) of 79.62 ± 0.11%. The in vitro release characterization revealed that DHA3NPs were easily hydrolysed into DHA in an esterase environment. The pharmacokinetics study demonstrated that the area under the concentration-time curve (AUC0-t) of DHA in DHA3NPs group was 2070.52 ± 578.76 h×ng×mL-1, which was higher than that of DHA and artesunate (AS) control groups (AUC0-t values of 724.18 ± 94.32 and 448.40 ± 94.45 h×ng×mL-1, respectively) (P < 0.05). The antimalarial pharmacodynamics in vivo suggested that DHA3NPS (ED90 7.82 ± 1.16 µmol×(kg×day)-1) had a superior antimalarial effect compared with that of control groups (ED90 values of 14.68 ± 0.98 (DHA) and 14.34 ± 1.96 (AS) µmol×(kg×day)-1) (P < 0.05). In addition, DHA3NPS reduced the recurrence ratio and improved the cure ratio and survival time. In summary, DHA3NPs exhibited promising pharmacokinetic characteristics and antimalarial pharmacodynamics in vivo.

10.
Nucleic Acids Res ; 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34268557

RESUMO

tRNAs harbor the most diverse posttranscriptional modifications. The 3-methylcytidine (m3C) is widely distributed at position C32 (m3C32) of eukaryotic tRNAThr and tRNASer species. m3C32 is decorated by the single methyltransferase Trm140 in budding yeasts; however, two (Trm140 and Trm141 in fission yeasts) or three enzymes (METTL2A, METTL2B and METTL6 in mammals) are involved in its biogenesis. The rationale for the existence of multiple m3C32 methyltransferases and their substrate discrimination mechanism is hitherto unknown. Here, we revealed that both METTL2A and METTL2B are expressed in vivo. We purified human METTL2A, METTL2B, and METTL6 to high homogeneity. We successfully reconstituted m3C32 modification activity for tRNAThr by METT2A and for tRNASer(GCU) by METTL6, assisted by seryl-tRNA synthetase (SerRS) in vitro. Compared with METTL2A, METTL2B exhibited dramatically lower activity in vitro. Both G35 and t6A at position 37 (t6A37) are necessary but insufficient prerequisites for tRNAThr m3C32 formation, while the anticodon loop and the long variable arm, but not t6A37, are key determinants for tRNASer(GCU) m3C32 biogenesis, likely being recognized synergistically by METTL6 and SerRS, respectively. Finally, we proposed a mutually exclusive substrate selection model to ensure correct discrimination among multiple tRNAs by multiple m3C32 methyltransferases.

11.
Am J Primatol ; : e23306, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34270109

RESUMO

In group-living mammals, an individual's fitness depends, in part, on the quality of social relationships it has with others. Among species of nonhuman primates in which one sex is philopatric, individuals of that sex often develop strong social bonds and alliances with closely related kin. Less is known regarding the social processes used by dispersing adults to form stable bonds with nonkin in their new group. From May to December 2009, April to August 2010, September to December 2011, and February to May 2012, we collected data on grooming interactions in wild Tibetan macaques (Macaca thibetana), a female philopatric species, at Mt. Huangshan, China. Our goal was to compare social interactions and bond formation between resident males, recent immigrant males, and resident females. Our results indicate that recent immigrant males formed stable partner relationships with a small number of resident females and groomed these females more frequently or for longer than they received grooming. In contrast, resident males switched female grooming partners more frequently, received more grooming than they gave, and formed relationships with a greater number of female partners. We argue that the ability of recent immigrant male Tibetan macaques to maintain strong and persistent social bonds with a small set of resident adult females is a primary factor that enables them to establish residence in a new multimale-multifemale group. The present study provides new and important insights into the integrated social strategies used by dispersing males and resident females to maintain group stability.

12.
Ann Palliat Med ; 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34263647

RESUMO

BACKGROUND: Stress urinary incontinence (SUI) is defined as involuntary leakage of urine from the external urethra due to increased abdominal pressure, for example, upon sneezing, coughing, or exercise. Acupuncture is an effective therapy for patients with SUI, although objective evidence of its benefits or mechanism of action is limited. Patients with SUI often harbor structural changes of pelvic floor, the parameters of which are measurable from various perspectives and in multiple dimensions, dynamically and comprehensively, through transperineal ultrasound (TPUS). The status of such changes may then be assessed following acupuncture procedures. In the present investigation, TPUS serves to gauge the immediate effects of acupuncture on pelvic floor structures in female patients with SUI. METHODS: This protocol calls for a prospective, randomized, controlled, and single-blinded study of 72 female patients with SUI, each randomly assigned as test or control group members. The test group is subjected to one-time acupuncture at the Zhongji (RN3) acupoint for a period of 10 min, whereas the control group undergoes sham acupuncture in the same manner. In both groups, TPUS imaging of pelvic floor is performed before, during, and immediately after acupuncture procedures. Bladder neck mobility (BND), urethral rotation angle (URA), retrovesical angle (RVA), lowest point of bladder (BN-S), and presence/absence of urethral funneling or bladder bulging are then recorded as outcome measures. DISCUSSION: Above efforts are intended to assess real-time pelvic floor structural changes in women undergoing acupuncture for SUI. The subsequent findings may help objectively document the efficacy of acupuncture in this setting and clarify its mechanism of action. TRIAL REGISTRATION: Registration with the Chinese Clinical Trial Registry (ChiCTR200041559) (http:// www.chictr.org.cn/edit.aspx?pid=64591&htm=4), was effective December 29, 2020. DATES OF STUDY: 12/19/2020 to 06/30/2022.

13.
Adv Sci (Weinh) ; : e2003708, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34258870

RESUMO

Islet transplantation has shown promise as a curative therapy for type 1 diabetes (T1D). However, the side effects of systemic immunosuppression and limited long-term viability of engrafted islets, together with the scarcity of donor organs, highlight an urgent need for the development of new, improved, and safer cell-replacement strategies. Induction of local immunotolerance to prevent allo-rejection against islets and stem cell derived ß cells has the potential to improve graft function and broaden the applicability of cellular therapy while minimizing adverse effects of systemic immunosuppression. In this mini review, recent developments in non-encapsulation, local immunomodulatory approaches for T1D cell replacement therapies, including islet/ß cell modification, immunomodulatory biomaterial platforms, and co-transplantation of immunomodulatory cells are discussed. Key advantages and remaining challenges in translating such technologies to clinical settings are identified. Although many of the studies discussed are preliminary, the growing interest in the field has led to the exploration of new combinatorial strategies involving cellular engineering, immunotherapy, and novel biomaterials. Such interdisciplinary research will undoubtedly accelerate the development of therapies that can benefit the whole T1D population.

14.
J Phys Chem Lett ; : 6919-6926, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34282920

RESUMO

The present work reports highly efficient flexible and reabsorption-free scintillators based on two zero-dimensional (0D) organic copper halides (TBA)CuX2 (TBA = tetrabutylammonium cation; X = Cl, Br). The (TBA)CuX2 exhibit highly luminescent green and sky-blue emissions peaked at 510 and 498 nm, with large Stokes shifts of 224 and 209 nm and high photoluminescence quantum yields (PLQYs) of 92.8% and 80.5% at room temperature for (TBA)CuCl2 and (TBA)CuBr2 single crystals (SCs), respectively. Interestingly, above room temperature, their PLQYs increase with temperature and reach near unity at 320 and 345 K for (TBA)CuCl2 and (TBA)CuBr2, respectively. The excellent properties originate from self-trapped excitons (STEs) in individual [CuX2]- quantum rods, which is demonstrated by the temperature-dependent PL, ultrafast transient absorption (TA) combined with density functional theory (DFT) calculations. The (TBA)CuX2 scintillators show bright radioluminescence (RL), impressive linear response to dose rate in a broad range, and high light yields. Their potential application in X-ray imaging is demonstrated by using (TBA)CuX2 composite scintillation screens. Importantly, flexible scintillators are demonstrated to be superior than flat ones for imaging nonplanar objects by conformally coating, which produce accurate images with negligible distortion.

15.
J Med Chem ; 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34279930

RESUMO

The development of a safe and effective COVID-19 vaccine is of paramount importance to terminate the current pandemic. An adjuvant is crucial for improving the efficacy of the subunit COVID19 vaccine. α-Galactosylceramide (αGC) is a classical iNKT cell agonist which causes the rapid production of Th1- and Th2-associated cytokines; we, therefore, expect that the Th1- or Th2-skewing analogues of αGC can better enhance the immunogenicity of the receptor-binding domain in the spike protein of SARS-CoV-2 fused with the Fc region of human IgG (RBD-Fc). Herein, we developed a universal synthetic route to the Th1-biasing (α-C-GC) and Th2-biasing (OCH and C20:2) analogues. Immunization of mice demonstrated that αGC-adjuvanted RBD-Fc elicited a more potent humoral response than that observed with Alum and enabled the sparing of antigens. Remarkably, at a low dose of the RBD-Fc protein (2 µg), the Th2-biasing agonist C20:2 induced a significantly higher titer of the neutralizing antibody than that of Alum.

16.
J Colloid Interface Sci ; 603: 651-665, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34225070

RESUMO

To fabricate high-quality catalysts with abundant active sites, a series of transition-metal-modified nitrogenous carbon catalysts (Ta-NOC, Nb-NOC, and Nb/Ta-NOC) was successfully fabricated via pyrolysis and ion exchange. Owing to the high conductivity and ion transport capacity of its unique nitrogen-carbon structure, and synergistic effect of dual-metal active sites on modulating electronic structure, Nb/Ta-NOC catalyst exhibited an excellent catalytic performance and a remarkable electrochemical stability in triiodide reduction reaction (IRR) and hydrogen evolution reaction (HER). Nb/Ta-NOC catalyst achieved an ideal conversion efficiency of 8.45% for IRR in solar cells, which was higher than that of Pt electrode (7.63%). Furthermore, Nb/Ta-NOC catalyst exhibited a small overpotential of 145 mV at a current density of 10 mA·cm-2 and a Tafel slope of 77 mV dec-1 for HER. This work provided a new approach for the rational design of the active-sites-rich electrocatalysts for energy conversion applications.

17.
J Colloid Interface Sci ; 604: 292-300, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34265686

RESUMO

Hollow structures draw much attention for high energy density supercapacitors due to their large hollow cavities, high specific surface area, and low interfacial contact resistance. However, constructing hierarchical hollow structures remains a challenge. Herein, we reported a facile template-free method for a novel urchin-like hollow nickel cobalt sulfide (NiCo2S4). The hollow interior and urchin exterior remarkably improved the specific capacitance and accommodated structural collapse caused by electrochemical reactions. Owing to these features, the urchin-like hollow NiCo2S4 spheres exhibited an impressive capacitance of 1398F g-1 at 1 A g-1 and maintained 1110F g-1 with a large current density of 10 A g-1. The hybrid supercapacitor fabricated by NiCo2S4 and active carbon possesses an energy density of 39.3 Wh kg-1 at a power density of 749.6 W kg-1 and an outstanding cycling stability of 74.4% retention after 5000 cycles. Our work presents a facile method of constructing a hollow structure of binary sulfide materials and also makes progress on highly efficient supercapacitors.

18.
J Colloid Interface Sci ; 604: 441-457, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34273781

RESUMO

Developing electrocatalysts with excellent catalytic performance and superior durability for hydrogen evolution reaction (HER) remains a challenge. Herein, metal-nitrogen sites (M-Nx, M = Ni and Cu) are successfully implanted into zeolitic imidazolate zinc framework (ZIF-8)-derived nitrogen-doped porous carbon (ZIF/NC) to prepare Ni-ZIF/NC and Cu-ZIF/NC electrocatalysts for the HER. These M-Nx active sites significantly enhanced the electrocatalytic activities of Ni-ZIF/NC and Cu-ZIF/NC. Metal Ni acted as a catalyst for catalysis of Ni-ZIF/NC to form carbon nanotubes-like structures, which provided convenient ion transmission pathways. Owing to its special morphology and an increased number of defects, Ni-ZIF/NC displayed superior electrocatalytic activity in the HER compared to those of Cu-ZIF/NC and ZIF/NC. In an alkaline environment, Ni-ZIF/NC exhibited an overpotential at the current density of 10 mA cm-2 (η10) of 163.0 mV and Tafel slope of 85.0 mV dec-1, demonstrating an electrocatalytic property equivalent to that of Pt/C. In an acidic environment, Ni-ZIF/NC yielded a η10 of 177.4 mV and Tafel slope of 83.9 mV dec-1, which were comparable to those of 20 wt.% Pt/C. Moreover, Ni-ZIF/NC and Cu-ZIF/NC also exhibited superior stabilities in alkaline environments. This work offers a valuable strategy for controlling the morphology and implanting M-Nx active sites into carbon for designing novel catalysts for use in alternative new energy applications.

19.
J Affect Disord ; 294: 128-136, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34284318

RESUMO

BACKGROUND: We aimed to explore the risk profiles attributable to psychosocial and behavioural problems during the coronavirus disease 2019 pandemic. To this end, we created a risk-prediction nomogram model. METHODS: A national multicentre study was conducted through an online questionnaire involving 12,186 children (6-11 years old) and adolescents (12-16 years old). Respondents' psychosocial and behavioural functioning were assessed using the Achenbach Child Behaviour Checklist (CBCL). Data were analysed using STATA software and R-language. RESULTS: The positive detection rate of psychological problems within Wuhan was greater than that outside Wuhan for schizoid (P = 0.005), and depression (P = 0.030) in children, and for somatic complaints (P = 0.048), immaturity (P = 0.023), and delinquent behaviour (P = 0.046) in adolescents. After graded multivariable adjustment, seven factors associated with psychological problems in children and adolescents outside Wuhan were parent-child conflict (odds ratio (OR): 4.94, 95% confidence interval (95% CI): 4.27-5.72), sleep problems (OR: 4.05, 95% CI: 3.77-4.36), online study time (OR: 0.41, 95% CI: 0.37-0.47), physical activity time (OR: 0.510, 95% CI: 0.44-0.59), number of close friends (OR: 0.51, 95% CI: 0.44-0.6), time spent playing videogames (OR: 2.26, 95% CI: 1.90-2.69) and eating disorders (OR: 2.71, 95% CI: 2.35-3.11) (all P < 0.001). Contrastingly, within Wuhan, only the first four factors, namely, parent-child conflict (5.95, 2.82-12.57), sleep problems (4.47, 3.06-6.54), online study time (0.37, 0.22-0.64), and physical activity time (0.42, 0.22-0.80) were identified (all P < 0.01). Accordingly, nomogram models were created with significant attributes and had decent prediction performance with C-indexes over 80%. LIMITATION: A cross-sectional study and self-reported measures. CONCLUSIONS: Besides the four significant risk factors within and outside Wuhan, the three additional factors outside Wuhan deserve special attention. The prediction nomogram models constructed in this study have important clinical and public health implications for psychosocial and behavioural assessment.

20.
Aging (Albany NY) ; 13(undefined)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285141

RESUMO

BACKGROUND: Epigenetic dysregulation has been increasingly proposed as a hallmark of cancer. Here, the aim of this study is to establish an epigenetic-related signature for predicting the prognosis of lung adenocarcinoma (LUAD) patients. RESULTS: Five epigenetic-related genes (ERGs) (ARRB1, PARP1, PKM, TFDP1, and YWHAZ) were identified as prognostic hub genes and used to establish a prognostic signature. According our risk score system, LUAD patients were stratified into high and low risk groups, and patients in the high risk group had a worse prognosis. ROC analysis indicated that the signature was precise in predicting the prognosis. A new nomogram was constructed based on the five hub genes, which can predict the OS of every LUAD patients. The calibration curves showed that the nomogram had better accuracy in prediction. Finally, candidate drugs that aimed at hub ERGs were identified, which included 47 compounds. CONCLUSIONS: Our epigenetic-related signature nomogram can effectively and reliably predict OS of LUAD patients, also we provide precise targeted chemotherapeutic drugs. METHODS: The genomic data and clinical data of LUAD cohort were downloaded from the TCGA database and ERGs were obtained from the EpiFactors database. GSE31210 and GSE50081 microarray datasets were included as independent external datasets. Univariate Cox, LASSO regression, and multivariate Cox analyses were applied to construct the epigenetic-related signature.

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