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1.
Nat Commun ; 13(1): 4600, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933410

RESUMO

High-performance and low-cost photocatalysts play the key role in achieving the large-scale solar hydrogen production. In this work, we report a liquid-exfoliation approach to prepare NiPS3 ultrathin nanosheets as a versatile platform to greatly improve the light-induced hydrogen production on various photocatalysts, including TiO2, CdS, In2ZnS4 and C3N4. The superb visible-light-induced hydrogen production rate (13,600 µmol h-1 g-1) is achieved on NiPS3/CdS hetero-junction with the highest improvement factor (~1,667%) compared with that of pure CdS. This significantly better performance is attributed to the strongly correlated NiPS3/CdS interface assuring efficient electron-hole dissociation/transport, as well as abundant atomic-level edge P/S sites and activated basal S sites on NiPS3 ultrathin nanosheets advancing hydrogen evolution. These findings are revealed by the state-of-art characterizations and theoretical computations. Our work for the first time demonstrates the great potential of metal phosphorous chalcogenide as a general platform to tremendously raise the performance of different photocatalysts.

2.
Front Mol Neurosci ; 15: 932075, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909453

RESUMO

Background: In previous studies, alkaline phosphatase (ALP) level was a prognostic factor for patients with ischemic stroke, and globulin level was associated with hemorrhagic transformation (HT) after intravenous thrombolysis (IVT). However, the association between these serum biomarkers and prognosis in patients with acute ischemic stroke (AIS) who undergo IVT remains unclear. This study aimed to investigate the characteristics of serum ALP and globulin levels after IVT and to assess the relationship between these serum biomarkers and prognosis. Materials and methods: This retrospective study used a prospectively collected database. We included patients with AIS who received recombinant tissue plasminogen activator (rt-PA) IVT. Demographic information, vascular risk factors, laboratory test results, and other stroke-related data were collected for analysis. Clinical outcomes included HT and 3-month poor outcome (modified Rankin Scale scores ≥ 2) after IVT. The association of ALP and globulin levels with HT and poor outcome was investigated using multivariate logistic regression analysis. An individualized prediction model based on ALP and globulin levels for functional outcomes was established. Results: We enrolled 750 patients in this study; 452 patients (60.3%) had poor outcome, and 117 patients (15.6%) had HT after IVT. After adjusting for all confounders, serum globulin level [OR = 1.055; 95% confidence intervals (CI): 1.006-1.107; P = 0.028] was independently associated with HT in patients with IVT. Serum ALP (OR = 1.009; 95% CI: 1.002-1.016; P = 0.010) and globulin levels (OR = 1.062; 95% CI: 1.020-1.107; P = 0.004) were associated with 3-month poor outcome in these patients. The constructed individualized prediction model for the 3-month poor outcome comprised the National Institutes of Health Stroke Scale (NIHSS) score, Trial of Org 10172 in Acute Stroke Treatment (TOAST), history of antihypertensive therapy, ALP and globulin levels. The area under the curve of the training and validation sets were 0.726 and 0.706, respectively, revealing that the model had good discriminating power. The P-values for the Hosmer-Lemeshow test in the training and validation sets were 0.978 and 0.148, respectively, indicating the model had good calibration. Conclusion: This study found that higher serum globulin levels were independently associated with HT. Additionally, higher serum ALP and globulin levels were independently associated with a poor outcome in patients after IVT.

3.
J Hypertens ; 40(9): 1744-1750, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35943102

RESUMO

OBJECTIVES: Increased blood pressure variability (BPV) over 24 h or longer was associated with poor clinical outcomes in patients with intracerebral haemorrhage (ICH). However, the characteristics of beat-to-beat BPV, a rapid assessment of BPV and its association with outcome in ICH patients remain unknown. METHODS: We consecutively and prospectively recruited patients with ICH between June 2014 and December 2020. Five-minute noninvasive beat-to-beat recordings were measured serially at three time points, 1-2, 4-6 and 10-12 days after ICH onset. BPV was calculated using standard deviation (SD) and variation independent of mean (VIM). Favourable outcome was defined as modified Rankin Scale score of less than 2 at 90 days. RESULTS: The analysis included 66 participants (54.12 ±â€Š10.79 years; 71.2% men) and 66 age and sex-matched healthy controls. Compared with that in healthy adults, beat-to-beat BPV was significantly increased 1-2 days after ICH and was completely recovered 10-12 days later. BPV recorded 1-2 days after ICH onset was higher among patients with unfavourable outcomes than among those with favourable outcomes (all P < 0.05) and higher BPV on days 1-2 was independently associated with a 3-month unfavourable outcome after adjustment for major covariates. CONCLUSION: Beat-to-beat BPV was significantly increased among patients with ICH and could be completely recovered 10-12 days later. In addition, beat-to-beat BPV 1-2 days after ICH was independently associated with prognosis and could be regarded as a potential prognostic predictor and effective therapeutic target in the future.

4.
Front Mol Neurosci ; 15: 879863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923753

RESUMO

Objective: Hyponatremia is the most common electrolyte disorder encountered in patients with neurological conditions, such as stroke. Studies have shown that it is associated with worse clinical outcomes and increased mortality in acute ischemic stroke (AIS). However, the role of hyponatremia has not been elucidated in patients with AIS who received intravenous thrombolysis (IVT) therapy. Therefore, this study aimed to investigate the effect of serum sodium levels on the clinical outcome and hemorrhagic transformation (HT) in patients with AIS who received thrombolytic therapy. Methods: Patients diagnosed with AIS who received IVT therapy between May 2015 and December 2020 were included in this study. All patients were screened for serum sodium levels immediately after hospital admission, before IVT therapy. The occurrence of HT was evaluated using computed tomography (CT) 24 ± 2 h after thrombolysis. Then, 3-month clinical outcomes were obtained by telephone calls or outpatient visits, and poor 3-month clinical outcomes were defined as modified Rankin Scale scores ≥3. The effects of serum sodium levels on the clinical outcome and HT were assessed using the multivariate logistic regression analysis. Results: Of the 963 included patients, 82 (8.5%) had hyponatremia, 157 (16.3%) developed HT, and 333 (34.6%) had poor 3-month outcomes. Of the 82 patients with hyponatremia, 21 (25.6%) developed HT, and 39 (47.6%) had poor 3-month outcomes. Patients with hyponatremia had a higher incidence of post-thrombolysis HT (25.6 vs. 15.4%, p = 0.017) and worse clinical outcome (47.6 vs. 33.4%, p = 0.01) than those with normal serum sodium levels. Patients had significantly lower serum sodium levels in those with HT [138.4 (136.4-140.3, IQR) vs. 139.0 (137.2-140.7, IQR) mmol/L, p = 0.019] and poor 3 month outcome [139.0 (137.2-140.7) vs. 138.4 (136.7-140.3) mmol/L, p = 0.005] than those without. After adjusting for major covariates, the multivariate logistic regression analysis revealed that lower serum sodium levels were independently associated with an increased risk of HT [odds ratio (OR) = 1.804; 95% CI: 1.048-3.105] and poor 3-month outcome (OR = 1.647; 95% CI: 1.012-2.679). Conclusion: Lower serum sodium level was an independent risk factor for post-thrombolysis HT and poor clinical outcome in patients with AIS who received thrombolytic therapy.

5.
Front Microbiol ; 13: 889374, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35859744

RESUMO

Calcium, as a second intracellular messenger, participate in various physiological and biochemical processes, including cell growth and proliferation, energy metabolism, information transfer, cell death, and immune response. Ca2+ channels or pumps in plasma and organelle membranes and Ca2+-related proteins maintain Ca2+ homeostasis by regulating Ca2+ inflow, outflow and buffering to avoid any adverse effects caused by Ca2+ overload or depletion. Thus, Ca2+ signaling also provides a target for virus invasion, replication, proliferation and release. After hijacking the host cell, viruses exploit Ca2+ signaling to regulate apoptosis and resist host immunity to establish persistent infection. In this review, we discuss cellular Ca2+ signaling and channels, interaction of calcium-associated proteins with viruses, and host cell fate, as well as the role of Ca2+ in cell death and antiviral response during viral infection.

6.
Tissue Eng Regen Med ; 2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35809187

RESUMO

Senescence is an inevitable natural life process that involves structural and functional degeneration of tissues and organs. Recently, the process of skin aging has attracted much attention. Determining a means to delay or even reverse skin aging has become a research hotspot in medical cosmetology and anti-aging. Dysfunction in the epidermis and fibroblasts and changes in the composition and content of the extracellular matrix are common pathophysiological manifestations of skin aging. Reactive oxygen species and matrix metalloproteinases play essential roles in this process. Stem cells are pluripotent cells that possess self-replication abilities and can differentiate into multiple functional cells under certain conditions. These cells also possess a strong ability to facilitate tissue repair and regeneration. Stem cell transplantation has the potential for application in anti-aging therapy. Increasing studies have demonstrated that stem cells perform functions through paracrine processes, particularly those involving exosomes. Exosomes are nano-vesicular substances secreted by stem cells that participate in cell-to-cell communication by transporting their contents into target cells. In this chapter, the biological characteristics of exosomes were reviewed, including their effects on extracellular matrix formation, epidermal cell function, fibroblast function and antioxidation. Exosomes derived from stem cells may provide a new means to reverse skin aging.

7.
Addict Behav ; 134: 107398, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35752086

RESUMO

AIMS: This study aimed to describe the prevalence of problematic mobile phone use (PMPU) and chronotype among Chinese college students, estimate PMPU development trajectories, and further examine the effect of PMPU trajectories on chronotype. DESIGN: In a stratified cluster sampling design, PMPU and chronotype were evaluated in 999 college students from two universities in a 2-year prospective investigation from April 2019 to April 2021, and an investigation was conducted every six months (time 1 âˆ¼ time 5, T1 âˆ¼ T5). PARTICIPANTS: N = 999 college students (mean age at T1: 18.8 years (SD = 1.2), 37.7% male) took part in the study. MEASUREMENTS: The Self-rating Questionnaire for Adolescent Problematic Mobile Phone Use (SQAPMPU) and the Pittsburgh Sleep Quality Index (PSQI) were used to assess the PMPU and sleep quality of college students at each time point. The Morning and Evening Questionnaire (MEQ) was adopted to investigate the chronotype of college students at T5. FINDINGS: The prevalence of PMPU at T1 âˆ¼ T5 was 24.3%, 27.3%, 35.1%, 31.2% and 31.9%, respectively. The prevalence rates of morning types (M-types), neutral types (N-types), and evening types (E-types) were 19.1%, 70.8%, and 10.1%, respectively. Using latent growth mixture modelling, we identified three trajectories of PMPU: low-level (49.5%), moderate-level (38.6%), and high-level score trajectories (11.9%). Multivariate logistic regression analysis results showed that a trajectory with a high score was positively associated with E-types (P < 0.05). After stratification by gender, a high-level score trajectory was positively associated with E-types only among female college students (P < 0.05). There were sex differences in the association between trajectories of PMPU and chronotype. CONCLUSION: Long-term symptoms of PMPU may be a potential risk factor for circadian rhythm disturbance among college students, and this effect was significantly different between genders.

8.
Nat Commun ; 13(1): 3335, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680936

RESUMO

The Madagascar's periwinkle is the model plant for studies of plant specialized metabolism and monoterpenoid indole alkaloids (MIAs), and an important source for the anticancer medicine vinblastine. The elucidation of entire 28-step biosynthesis of vinblastine allowed further investigations for the formation of other remarkably complex bioactive MIAs. In this study, we describe the discovery and characterization of vindolinine synthase, a Fe(II)/α-ketoglutarate-dependent (Fe/2OG) dioxygenase, that diverts assembly of tabersonine to vinblastine toward the formation of three alternatively cyclized MIAs: 19S-vindolinine, 19R-vindolinine, and venalstonine. Vindolinine synthase catalyzes a highly unusual, redox-neutral reaction to form a radical from dehydrosecodine, which is further cyclized by hydrolase 2 to form the three MIA isomers. We further show the biosynthesis of vindolinine epimers from tabersonine using hydrolase 2 catalyzed reverse cycloaddition. While the occurrence of vindolinines is rare in nature, the more widely found venalstonine derivatives are likely formed from similar redox-neutral reactions by homologous Fe/2OG dioxygenases.


Assuntos
Catharanthus , Alcaloides de Triptamina e Secologanina , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Catharanthus/metabolismo , Compostos Ferrosos/metabolismo , Regulação da Expressão Gênica de Plantas , Hidrolases/metabolismo , Oxirredução , Proteínas de Plantas/genética , Alcaloides de Triptamina e Secologanina/metabolismo , Vimblastina/análogos & derivados , Vimblastina/metabolismo
9.
Methods Mol Biol ; 2505: 69-77, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35732937

RESUMO

The plant Catharanthus roseus is well known for its spatial separation of iridoid and monoterpenoid indole alkaloid (MIA) biosynthesis at both intracellular and intercellular levels, collectively suggested by RNA in situ hybridization, enzymatic and transcriptomic studies using leaf epidermis, and fluorescent protein tagging studies. Although documented in other plant species, the long-distance transport of iridoid glycosides, such as secologanin, has not been known in C. roseus until a recent study suggested that secologanin is transported from root to shoot, by grafting low iridoid/MIA mutant scions onto wild-type stock plants. This chapter describes the in vitro cultivation of C. roseus plants and grafting techniques to enable studies concerning iridoid/MIA transport between organs. The iridoid and MIA analysis methods are also provided.


Assuntos
Catharanthus , Catharanthus/genética , Catharanthus/metabolismo , Regulação da Expressão Gênica de Plantas , Iridoides/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
10.
Methods Mol Biol ; 2505: 181-190, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35732945

RESUMO

Decades of research on the medicinal plant Catharanthus roseus have led to the complete elucidation of the 29-step pathway for the biosynthesis of the anticancer drug vinblastine from geraniol and tryptophan precursors. Several approaches have been used to identify the enzymes involved in this iconic and remarkably complex pathway. This chapter describes the use of the classic ethyl methanesulfonate (EMS) mutagenesis to create a selfed M2 mutant population, which can be rapidly screened to select mutants with altered monoterpenoid indole alkaloid (MIA) biosynthesis with a simple, high-throughput thin-layer chromatography (TLC)-based screening strategy. This TLC-based MIA screening has led to the discovery and characterization of three enzymes responsible for vinblastine biosynthesis.


Assuntos
Catharanthus , Alcaloides de Triptamina e Secologanina , Catharanthus/genética , Catharanthus/metabolismo , Cromatografia em Camada Delgada , Metanossulfonato de Etila , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Vimblastina
11.
Comput Intell Neurosci ; 2022: 3475679, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720942

RESUMO

Iron tailings sand is a kind of mineral waste, and open-air storage is a common treatment method for iron tailings, which not only has a huge impact on the ecological environment but also occupies a lot of land resources. Therefore, the preparation of high-ductility fiber reinforced iron tailings concrete and its application in practical engineering structures have good application prospects. This paper is based on the deep learning research on the mechanical and carbonization properties of hybrid fiber iron tailings concrete. Therefore, tailings sands with different substitution rates, single-mixed steel fiber, and mixed steel-PVA fiber concrete were prepared in this paper. Its compressive strength, split tensile strength, axial compressive strength, elastic modulus, strain, and carbonization depth were tested. Through the existing concrete compressive stress-strain curve equations, the nonlinear calculation of each group of concrete compressive stress-strain curve equations in this paper is carried out, some parameters are determined, and the carbonation depth equation is established. The results show that, with the increase of tailings content, the properties of concrete increase first and then decrease and the addition of fibers can effectively improve the strength, elastic modulus, peak strain, and carbonization depth of concrete. However, with the increase of PVA fiber content, its performance enhancement effect decreased.


Assuntos
Aprendizado Profundo , Ferro , Engenharia , Meio Ambiente , Aço
12.
Nanomaterials (Basel) ; 12(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35564273

RESUMO

Nitrogen (N) doping is an effective strategy for improving the solar-driven photocatalytic performance of anatase TiO2, but controllable methods for nitrogen-rich doping and associated defect engineering are highly desired. In this work, N-rich doped anatase TiO2 nanoparticles (4.2 at%) were successfully prepared via high-temperature nitridation based on thermally stable H3PO4-modified TiO2. Subsequently, the associated deep-energy-level defects such as oxygen vacancies and Ti3+ were successfully healed by smart photo-Fenton oxidation treatment. Under visible-light irradiation, the healed N-doped TiO2 exhibited a ~2-times higher activity of gas-phase acetaldehyde degradation than the non-treated one and even better than standard P25 TiO2 under UV-visible-light irradiation. The exceptional performance is attributed to the extended spectral response range from N-rich doping, the enhanced charge separation from hole capturing by N-doped species, and the healed defect levels with the proper thermodynamic ability for facilitating O2 reduction, depending on the results of ∙O2- radicals and defect measurement by electron spin resonance, X-ray photoelectron spectroscopy, atmosphere-controlled surface photovoltage spectra, etc. This work provides an easy and efficient strategy for the preparation of high-performance solar-driven TiO2 photocatalysts.

13.
Micromachines (Basel) ; 13(5)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35630223

RESUMO

We experimentally demonstrate enhanced spectral broadening of femtosecond optical pulses after propagation through silicon-on-insulator (SOI) nanowire waveguides integrated with two-dimensional (2D) graphene oxide (GO) films. Owing to the strong mode overlap between the SOI nanowires and the GO films with a high Kerr nonlinearity, the self-phase modulation (SPM) process in the hybrid waveguides is significantly enhanced, resulting in greatly improved spectral broadening of the femtosecond optical pulses. A solution-based, transfer-free coating method is used to integrate GO films onto the SOI nanowires with precise control of the film thickness. Detailed SPM measurements using femtosecond optical pulses are carried out, achieving a broadening factor of up to ~4.3 for a device with 0.4-mm-long, 2 layers of GO. By fitting the experimental results with the theory, we obtain an improvement in the waveguide nonlinear parameter by a factor of ~3.5 and in the effective nonlinear figure of merit (FOM) by a factor of ~3.8, relative to the uncoated waveguide. Finally, we discuss the influence of GO film length on the spectral broadening and compare the nonlinear optical performance of different integrated waveguides coated with GO films. These results confirm the improved nonlinear optical performance of silicon devices integrated with 2D GO films.

14.
PeerJ ; 10: e13341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35505678

RESUMO

In this study, the effect of strip clear-cutting on the natural regeneration performance of mature Pinus tabuliformis plantations in the three locations in western part of the Liaoning Province was analyzed. Strip clear-cutting, with clear-cut and uncut strip widths of 15, 20, 25 m, and 10 and 18 m, respectively, was conducted in spring 2014, and control, in each study location. Field investigations were conducted in 2017. Fifteen sample plots with sizes of 4 m2 (2 m × 2 m) were established in each clear-cut strip, uncut strip, and control. One to four saplings were randomly selected to measure the current year increment, and the lengths and numbers for branch of the first whorl. Three saplings were randomly selected from the center of the strip to measure the photosynthetic rate. Three sample plots with sizes of 4 m2 (2 m × 2 m) and 1 m2 (1 m × 1 m) were developed in each strip and control to determine the biodiversity of shrubs and herbs as well as the water content of the decomposition and semi-decomposition layer. The results show that the current year increment and branch length of the first whorl can be ordered as follows: clear-cut strips > control > uncut strips. Number of the branches of the first whorl can be ordered as follows: clear-cut strips > uncut strips > control. Strip clear-cutting was a statistically significant treatment for the current year increment and length and number of branches of the first whorl. The saplings from the clear-cut strip with a width of 25 m have the largest photosynthetic capacity compared with those from the other strips and control. The transpiration rates of the large, medium, and small saplings from clear-cut strips are the largest and those of saplings from the control are the smallest. The water content of the decomposition and semi-decomposition layer in the control is the highest, but no significant difference was confirmed between the strip clear-cutting approaches.

15.
Int J Stroke ; : 17474930221104991, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35619218

RESUMO

RATIONALE: Remote ischemic conditioning (RIC) combined with intravenous thrombolysis (IVT) may improve functional outcomes in patients with acute ischemic stroke (AIS). AIM: To assess the efficacy and safety of RIC combined with IVT for AIS. METHODS AND DESIGN: SERIC-IVT is a multicenter, randomized, parallel-controlled, blinded endpoint clinical trial. A total of 558 patients with AIS who underwent IVT therapy will be randomly assigned 1:1 to receive RIC or sham-RIC plus standard medical therapy. The cuff pressures of the RIC group and the sham-RIC group will be 200 mm Hg and 60 mm Hg, respectively, performed twice a day for seven consecutive days. STUDY OUTCOMES: The primary efficacy outcome is the proportion of patients with a favorable functional outcome as defined as a modified Rankin Scale ⩽ 1 at 90 days. Safety outcomes include mortality and adverse events within 90 days. SAMPLE SIZE ESTIMATES: A sample size of 558 patients with AIS (279 in each group) will allow detection of a shift of 13.14% toward favorable functional outcome at 90 days (modified Rankin Scale ⩽ 1) with 5% significance and 80% power. DISCUSSION: RIC is a promising adjuvant treatment for AIS. SERIC-IVT will inform on whether RIC treatment combined with IVT improves functional outcomes in AIS patients and identify any safety issues.

16.
Colloids Surf B Biointerfaces ; 215: 112526, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35512561

RESUMO

Most chemotherapy agents have serious side effects due to lack of tumor targeting, which affects their clinical application. In addition, as an essential characteristic of malignant tumor, hypoxia is attracting exclusive research focus regarding its non-invasive real-time tracing in novel targeting delivery system. Herein, we designed a mixed micelle with tumor targeting and hypoxia responsiveness for tumor therapy and imaging. In particular, the dual-modified mix micelles were self-assembled by folic acid (FA) and 2-(2-nitroimidazole) ethylamine (NI) conjugated polymers, in which paclitaxel (PTX) and quantum dots (QDs) were co-loaded into the hydrophobic core. The drug loaded micelles showed satisfactory drug encapsulation, good storage stability, and sustained release properties. In vitro cell experiments showed that the mixed micelles exhibited enhanced cytotoxic effect and improved the cellular uptake, especially under hypoxic conditions, which was due to the FA mediated active targeting effect and NI induced hypoxic responsive release. In vivo experiments further proved that the mixed micelles possessed outstanding tumor targeting and hypoxia responsive properties. Furthermore, the drug loaded micelles showed excellent anti-tumor effect and can realize real-time in vivo imaging. This work demonstrates that the dual-modified mixed micelles co-loading with PTX and QDs might provide a novel approach for tumor therapy and imaging.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/química , Ácido Fólico/química , Humanos , Hipóxia , Micelas , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Paclitaxel/química
17.
Pharmaceuticals (Basel) ; 15(4)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35455477

RESUMO

Although polymeric platinum(IV) (Pt(IV)) prodrugs can reduce the side effects of cisplatin, the efficacy of the prodrug is still limited by its non-targeted distribution, poor penetration in deep tumor tissue, and low cytotoxicity in tumor cells. To improve the clinical potential of polymeric prodrug micelle, we synthesized amphiphilic polymeric Pt(IV) with high Pt content (22.5%), then developed a theranostic nanocomplex by integrating polymeric Pt(IV) with superparamagnetic Mn0.6Zn0.4Fe2O4 via simple self-assembly. Due to the high content of Mn0.6Zn0.4Fe2O4 (41.7% w/w), the theranostic nanocomplex showed high saturation magnetization (103.1 emu g-1) and excellent magnetocaloric effect (404 W g-1), both of them indicating its advantages in efficient magnetic targeting (MT), magnetic hyperthermia (MH), and magnetic resonance imaging (MRI). In vitro, in combination with MH, the theranostic nanocomplex showed as high cytotoxicity as cisplatin because of a significant increase in platinum of cellular uptake. In vivo, the accumulation of theranostic nanocomplex in tumors was increased by MT and confirmed by MRI. Furthermore, MH improved penetration of theranostic nanocomplex in tumors as expanding blackened area in tumors was observed by MRI. Based on these properties, the theranostic nanocomplex, under the assistance of MT and MH, showed the highest tumor growth inhibition rate (88.38%) after different treatments, while the body weight of mice increased slightly, indicating low side effects compared to those of cisplatin. The study provided an advanced theranostic nanocomplex with low toxicity and high efficacy, indicating a great clinical potential of polymeric Pt(IV).

18.
Bull Environ Contam Toxicol ; 109(1): 61-67, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35412056

RESUMO

The present study performed a continuous mode of bioleaching to investigate the leaching efficiency of Titanium (Ti) from bauxite residue using Penicillium Tricolor at between 4% and 12% pulp densities during a 120-day running. Obtained results of the current study showed that increased pulp density led to a decrease in biomass, dissolved oxygen, and amount of leaching Ti as well as an increase in pH value. Further, it was found that efficiency of bioleaching can be enhanced by increasing the rate of aeration, retention time, and concentration of carbon source. However, it was also evident that, at high pulp density, excessive agitation did not give an expected leaching efficiency but a collapse of biomass. In addition, results of the present study showed that the maximum leaching amount of Ti was 3202 mg/L with a corresponding leaching ratio of 50.35% during the whole bioleaching process. Moreover, it was noted that the biomass showed a significant negative correlation with the pH value and dissolved oxygen. However, the biomass showed a significant positive correlation with leaching amount of Ti and thus indicate that microbial metabolic activities are the uppermost factor affecting the continuous leaching performance.


Assuntos
Óxido de Alumínio , Penicillium , Oxigênio/metabolismo , Penicillium/metabolismo , Titânio
19.
Angew Chem Int Ed Engl ; 61(22): e202201886, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35293091

RESUMO

A multiple resonance thermally activated delayed fluorescence (MR-TADF) molecule with a fused, planar architecture tends to aggregate at high doping ratios, resulting in broad full width at half maximum (FWHM), redshifting electroluminescence peaks, and low device efficiency. Herein, we propose a mono-substituted design strategy by introducing spiro-9,9'-bifluorene (SBF) units with different substituted sites into the MR-TADF system for the first time. As a classic steric group, SBF can hinder interchromophore interactions, leading to high device efficiency (32.2-35.9 %) and narrow-band emission (≈27 nm). Particularly, the shield-like molecule, SF1BN, seldom exhibits a broadened FWHM as the doping ratio rises, which differs from the C3-substituted isomer and unhindered parent emitter. These results manifest an effective method for constructing highly efficient MR-TADF emitters through a spiro strategy and elucidate the feasibility for steric modulation of the spiro structure in π-framework.

20.
Front Physiol ; 13: 835173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35273521

RESUMO

Objective: Recent studies have demonstrated the positive roles of remote ischemic conditioning (RIC) in patients with cerebrovascular diseases; however, the mechanisms remain unclear. This study aimed to explore the effect of serial RIC on dynamic cerebral autoregulation (dCA) and serum biomarkers associated with brain injury, both of which are related to the prognosis of cerebrovascular disease. Methods: This was a self-controlled interventional study in healthy adults. The RIC was conducted twice a day for 7 consecutive days (d1-d7) and comprised 4 × 5-min single arm cuff inflation/deflation cycles at 200 mmHg. All participants underwent assessments of dCA ten times, including baseline, d1, d2, d4, d7, d8, d10, d14, d21, and d35 of the study. Blood samples were collected four times (baseline, d1, d7, and d8) immediately after dCA measurements. The transfer function parameters [phase difference (PD) and gain] were used to quantify dCA. Four serum biomarkers associated with brain injury, ubiquitin C-terminal hydrolase-L1, neuron-specific enolase, glial fibrillary acidic protein, and S100ß were tested. Results: Twenty-two healthy adult volunteers (mean age 25.73 ± 1.78 years, 3 men [13.6%], all Asian) were enrolled in this study. Bilateral PD values were significantly higher since four times of RIC were completed (d2) compared with PD values at baseline (left: 53.31 ± 10.53 vs. 45.87 ± 13.02 degree, p = 0.015; right: 54.90 ± 10.46 vs. 45.96 ± 10.77 degree, p = 0.005). After completing 7 days of RIC, the significant increase in dCA was sustained for at least 28 days (d35, left: 53.11 ± 14.51 degree, P = 0.038; right: 56.95 ± 14.57 degree, p < 0.001). No difference was found in terms of different serum biomarkers related to brain injury before and after RIC. Conclusion: The elevation in dCA was detected immediately after four repeated times of RIC, and 7-day consecutive RIC induced a sustained increase in dCA for at least 28 days and did not affect blood biomarkers of brain injury in healthy adults. These results will help us to formulate detailed strategies for the safe and effective application of RIC in patients with cerebrovascular disease.

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