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1.
J Ethnopharmacol ; 282: 114581, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34464697

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The diterpenoids extracted from Euphorbia kansui S.L. Liou ex S.B.Ho, Euphorbia fischeriana Steud. have good antitumor effects. Jolkinolide B has anti-breast cancer effect, but it is unclear whether it has different therapeutic effects between luminal A subtype and luminal B subtype breast cancer. AIM OF THE STUDY: This study investigated the Jolkinolide B has different therapeutic, important targets and pathways effects between luminal A subtype and luminal B subtype breast cancer. MATERIALS AND METHODS: We used bioinformatics to predict the biological process and molecular mechanism of Jolkinolide B in treating two types of breast cancer. Then, in vitro, cultured MCF-7 cells and BT-474 cells were divided into control group, PI3K inhibitor + control group, Jolkinolide B group and PI3K inhibitor + Jolkinolide B group. The CCK-8 assay, Flow cytometric analysis and Transwell cell migration assay was used to detect the cell proliferation, apoptosis, and migration in each group, respectively. ELISA was used to measure the content of Akt and phosphorylated Akt (p-Akt) in cell lysis buffer. RESULTS: Compared to luminal A breast cancer, Jolkinolide B had more targets, proliferation, migration processes and KEGG pathways when treating luminal B subtype breast cancer. Jolkinolide B significantly prolonged the survival time of luminal B subtype breast cancer patients. Compared to the control group, the cell proliferation absorbance value (A value) and migration number of the two kinds of breast cancer cells in the Jolkinolide B group were decreased (P < 0.01, n = 6), and the number of apoptotic cells was increased (P < 0.01, n = 6). Compared to the Jolkinolide B group, the A value and migration number of the two types of breast cancer cells were significantly decreased in the PI3K inhibitor + Jolkinolide B group (P < 0.01, n = 6), and the number of apoptotic cells was significantly increased (P < 0.01, n = 6). In addition, compared to MCF-7 cells, the A value and migration number of BT-474 cells stimulated with Jolkinolide B were significantly decreased (P < 0.01, n = 6), and the number of apoptotic cells was significantly increased (P < 0.01, n = 6). Akt and p-Akt protein levels in the two breast cancer cell lines in the Jolkinolide B group were all decreased (P < 0.01, n = 6), especially in BT-474 cells stimulated by Jolkinolide B. CONCLUSION: Jolkinolide B regulates the luminal A and luminal B subtypes of breast cancer through PI3K-Akt, EGFR and other pathways. Jolkinolide B has more significant therapeutic effect on luminal B subtype breast cancer. In vitro, experiments verified that Jolkinolide B significantly inhibited the proliferation and migration activity of BT-474 breast cancer cells by downregulating the PI3K-Akt pathway.

2.
J Hazard Mater ; 423(Pt A): 127010, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34474368

RESUMO

BTEX and chlorinated aliphatic hydrocarbons (CAHs) are the common pollutants found at contaminated sites, and natural attenuation (NA) of CAHs was widely observed where they coexist. In this work, the groundwater in a site co-contaminated with BTEX and CAHs was monitored for 1 year. The compositions and activities of the microfloras, especially dechlorinators and their relationships with the contaminants, geochemical properties, seasons and depth were evaluated. The results are consistent with the well-known NA conceptual model where CAHs are not able to stimulate the enrichment of dechlorinators alone, but BTEX does promote dechlorination. The higher temperature, rather than ORP in the deeper groundwater of the wet season became a key factor to promote the abundance of dechlorinators, but only when BTEX was available, indicating that the substrates from the BTEX biodegradation played an important role in the dechlorinator enrichment. The elevated ORP in the shallower groundwater exceeded the optimum conditions for reductive dechlorination and no significant seasonal variation of dechlorinators was found. The co-occurrence network revealed the cooperative interactions among the functional microfloras in which dechlorinators, BTEX degraders, and fermentative bacteria jointly promoted the dechlorination. These findings provided us a further understanding of the NA processes in a commingled plume.

3.
J Colloid Interface Sci ; 606(Pt 2): 1811-1822, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34507172

RESUMO

Highly dispersed Pt nanoparticles supported UiO-66 catalysts were successfully prepared by the incipient wetness impregnation method. Their thermal catalytic performances were evaluated by toluene degradation. The physicochemical properties of the samples were characterized using a series of characterization methods. The catalytic activity of catalysts remained essentially unchanged in the high weight hourly space velocity, stability and water resistance test, which also indicated good catalytic performance. In the reusability test, the catalytic performance was found to be enhanced after the reaction, because of the catalyst might follow a Pt0-PtO synergistic catalytic mechanism (similar to Mars-van Krevelen mechanism) and there was a phase transition between Pt0 and PtO during the reaction. Firstly, the toluene adsorbed on the catalyst surface was oxidized by the activated lattice oxygen of the PtO. Then, consumption of oxygen atoms led to formation of oxygen vacancies, and finally the molecular oxygen adsorbed by Pt0 was activated and passed to the PtO to supplement the oxygen vacancies, forming a redox cycle. In addition, the possible catalytic oxidation mechanism of toluene was also revealed.

4.
J Colloid Interface Sci ; 606(Pt 2): 941-952, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34487941

RESUMO

Batch experiments were conducted to study the Cr(VI) removal by nanoscale zero valent iron and copper intercalated montmorillonite (MMT-nFe0/Cu0) nanocomposite. MMT-nFe0/Cu0 was characterized using SEM, TEM, XRD, FTIR, N2 adsorption-desorption isotherms and XPS. The results demonstrated that highly dispersed nanoscale Fe0/Cu0 (nFe0/Cu0) were successfully introduced into the montmorillonite (MMT) layers. In the reaction process, the combination of Cu0 and Fe0 acted as a galvanic cell, and electrocorrosion not only speeded up the reaction rate, but also increased reduction activity of nFe0. MMT-nFe0/Cu0 as an excellent carrier had good functions in dispersing nFe0 and Cu0 particles, pH buffering and could keep nFe0 and Cu0 particles from being released. Besides, no iron ions and very low concentrations of copper ions released in the reaction system, which greatly avoided the influence of secondary environmental pollution.


Assuntos
Ferro , Poluentes Químicos da Água , Bentonita , Cromo/análise , Cobre , Poluentes Químicos da Água/análise
5.
Front Plant Sci ; 12: 756956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721486

RESUMO

Increasing attention has been given to the impact of extreme drought stress on ecosystem ecological processes. Ecosystem respiration (Re) and soil respiration (Rs) play a significant role in the regulation of the carbon (C) balance because they are two of the largest terrestrial C fluxes in the atmosphere. However, the responses of Re and Rs to extreme drought in alpine regions are still unclear, particularly with respect to the driver mechanism in plant and soil extracellular enzyme activities. In this study, we imposed three periods of extreme drought events based on field experiments on an alpine peatland: (1) early drought, in which the early stage of plant growth occurred from June 18 to July 20; (2) midterm drought, in which the peak growth period occurred from July 20 to August 23; and (3) late drought, in which the wilting period of plants occurred from August 23 to September 25. After 5 years of continuous extreme drought events, Re exhibited a consistent decreasing trend under the three periods of extreme drought, while Rs exhibited a non-significant decreasing trend in the early and midterm drought but increased significantly by 58.48% (p < 0.05) during the late drought compared with the ambient control. Plant coverage significantly increased by 79.3% (p < 0.05) in the early drought, and standing biomass significantly decreased by 18.33% (p < 0.05) in the midterm drought. Alkaline phosphatase, polyphenol oxidase, and peroxidase increased significantly by 76.46, 77.66, and 109.60% (p < 0.05), respectively, under late drought. Structural equation models demonstrated that soil water content (SWC), pH, plant coverage, plant standing biomass, soil ß-D-cellobiosidase, and ß-1,4-N-acetyl-glucosaminidase were crucial impact factors that eventually led to a decreasing trend in Re, and SWC, pH, ß-1,4-glucosidase (BG), ß-1,4-xylosidase (BX), polyphenol oxidase, soil organic carbon, microbial biomass carbon, and dissolved organic carbon were crucial impact factors that resulted in changes in Rs. Our results emphasize the key roles of plant and soil extracellular enzyme activities in regulating the different responses of Re and Rs under extreme drought events occurring at different plant growth stages.

6.
Technol Cancer Res Treat ; 20: 15330338211052142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34761715

RESUMO

Background: Identification of novel biomarkers is crucial for the diagnosis and treatment of esophageal squamous cell carcinoma (ESCC). This study aimed to reveal the clinical significance and molecular characteristics of MYC-associated factor X dimerization protein 1 (MXD1) in ESCC. Patients and methods: We collected 3 ESCC cohorts to investigate the effect of MXD1 on clinical outcomes. In addition, we compared and analyzed the possible transcription changes between MXD1-low and MXD1-high ESCC patients using bioinformatics. Moreover, immunohistochemical analysis was conducted to confirm the potential impact of MXD1 on the prognosis and tumor immune microenvironment (TIME). Results: MXD1 messenger RNA (mRNA) expression was significantly lower in tumors than in normal tissues. Low expression of MXD1 in ESCC was associated with a more aggressive tumor stage and worse prognosis at both the mRNA and protein levels. Moreover, MXD1-low ESCC showed upregulation of epithelial-mesenchymal transition and extracellular matrix-related gene sets, and significantly higher NFE2L2 and KIAA1324L mutation frequencies. In contrast, MXD1-high ESCC showed upregulation of tumor differentiation and immune-related gene sets. Furthermore, the CIBERSORT approach showed that high expression of MXD1 was associated with a higher proportion of neutrophils but a lower proportion of M2 macrophages. At the protein level, MXD1 expression was positively correlated with programmed cell death 1 ligand 1 (PDL1) and CD8 expression. In silico analysis predicted that MXD1-high ESCC was more likely to benefit from immunotherapy. Conclusion: This study suggests that MXD1 is a crucial prognostic factor in ESCC patients and is closely associated with specific transcriptional changes and TIME features.

7.
J Hazard Mater ; 424(Pt C): 127596, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34808448

RESUMO

The antibiotics pollution has currently captured increasing concerns due to its potential hazards to the environment and human health. The development of efficient and viable techniques for the removal of antibiotics is one of the research hotspots in fields of wastewater treatment and pharmaceutical industry. Although the photodegradation of antibiotics is widely studied, the evolution and toxicity of degradation intermediates have been rarely documented. Herein, Pt nanoparticles (NPs) decorated BiVO4 nanosheets (Pt/BiVO4 NSs) that exhibit excellent tetracycline (TC) photodegradation activity and stability have been prepared. Especially, the TC degradation efficiency reaches ca. 88.5% after 60 min under visible light irradiation, which is superior to most of the metal loaded two-dimensional photocatalysts reported hitherto. The excellent photocatalytic activity is attributable to the enhanced light absorption capacity and charge separation efficiency in Pt/BiVO4 NSs. h+, •O2- and •OH are the main active species for TC degradation, resulting in three possible degradation pathways. Furthermore, we first verify that TC solutions treated by Pt/BiVO4 NSs are harmless to Escherichia coli K-12 and various bacteria in natural rivers, which would not stimulate Escherichia coli to produce antibiotics resistance genes (ARGs). This work develops an environmentally friendly photodegradation strategy using Pt/BiVO4 NSs with potentials for efficient remediation of antibiotics pollution in wastewater.

8.
J Nanobiotechnology ; 19(1): 377, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34798888

RESUMO

BACKGROUND: As we know, radiotherapy plays an irreplaceable role in the clinical management on solid tumors. However, due to the non-specific killing effects of ionizing radiation, normal tissues damages would be almost simultaneous inevitably. Therefore, ideal radioprotective agents with high efficiency and low toxicity are always desirable. In this work, atomically precise Ag14 clusterzymes were developed, and their applications in radioprotection were studied in vitro and in vivo for the first time. METHODS: The ultra-small glutathione supported Ag14 clusterzymes were synthesized by convenient sodium borohydride (NaBH4) reduction of thiolate-Ag (I) complexes and then they were purified by desalting columns. The enzyme-like activity and antioxidant capacity of Ag14 clusterzymes have been tested by various commercial kits, salicylic acid method and electron spin resonance (ESR). Next, they were incubated with L929 cells to evaluate whether they could increase cell viability after γ-ray irradiation. And then Ag14 clusterzymes were intravenously injected into C57 mice before 7 Gy whole-body γ-ray irradiation to evaluate the radioprotection effects in vivo. At last, the in vivo toxicities of Ag14 clusterzymes were evaluated through biodistribution test, hematological details, serum biochemical indexes and histological test in female Balb/c mice with intravenous injection of Ag14 clusterzymes. RESULTS: Our studies suggested atomically precise Ag14 clusterzymes were potential radioprotectants. Ag14 clusterzymes exhibited unique superoxide dismutase (SOD)-like activity, strong anti-oxidative abilities, especially on •OH scavenging. The Ag14 clusterzymes could effectively improve cell viability through eliminating ROS and prevent DNA damages in cells dealt with γ-ray irradiation. In vivo experiments showed that Ag14 clusterzymes could improve the irradiated mice survival rate by protecting hematological systems and repairing tissue oxidative stress damage generated by γ-ray irradiation. In addition, bio-distribution and toxicological experiments demonstrated that the ultrasmall Ag14 clusterzymes could be excreted quickly from the body by renal clearance and negligible toxicological responses were observed in mice up to 30 days. CONCLUSION: In summary, atomically precise, ultrasmall and water soluble Ag14 clusterzymes with SOD-like activity were successfully developed and proved to be effective both in vitro and in vivo for radioprotection. Furthermore, with atomically precise molecular structure, Ag14 clusterzymes, on aspect of the catalytic and optical properties, may be improved by structure optimization on atom-scale level for other applications in disease diagnosis and treatment.

9.
Opt Express ; 29(22): 36535-36545, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34809062

RESUMO

The rapid and sensitive detection of plant-growth-regulator (PGR) residue is essential for ensuring food safety for consumers. However, there are many disadvantages in current approaches to detecting PGR residue. In this paper, we demonstrate a highly sensitive PGR detection method by using terahertz time-domain spectroscopy combined with metamaterials. We propose a double formant metamaterial resonator based on a split-ring structure with titanium-gold nanostructure. The metamaterial resonator is a split-ring structure composed of a titanium-gold nanostructure based on polyimide film as the substrate. Also, terahertz spectral response and electric field distribution of metamaterials under different analyte thickness and refractive index were investigated. The simulation results showed that the theoretical sensitivity of resonance peak 1 and peak 2 of the refractive index sensor based on our designed metamaterial resonator approaches 780 and 720 gigahertz per refractive index unit (GHz/RIU), respectively. In experiments, a rapid solution analysis platform based on the double formant metamaterial resonator was set up and PGR residues in aqueous solution were directly and rapidly detected through terahertz time-domain spectroscopy. The results showed that metamaterials can successfully detect butylhydrazine and N-N diglycine at a concentration as low as 0.05 mg/L. This study paves a new way for sensitive, rapid, low-cost detection of PGRs. It also means that the double formant metamaterial resonator has significant potential for other applications in terahertz sensing.

10.
Microbiol Spectr ; : e0123121, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34730415

RESUMO

The spread of multidrug-resistant (MDR) Gram-negative bacteria (GNB) has led to serious public health problems worldwide. Colistin, as a "last resort" for the treatment of MDR bacterial infections, has been used significantly in recent years and has led to the continuous emergence of colistin-resistant strains. In this study, we aimed to investigate the synergistic effect on the antimicrobial and antibiofilm activities of a colistin/furanone C-30 combination against colistin-resistant GNB in vitro and in vivo. According to antimicrobial resistance profiles, most of the colistin-resistant strains we collected showed MDR phenotypes. The checkerboard method and time-kill curve showed that the combination with furanone C-30 increases the antibacterial activity of colistin significantly. In addition, the furanone C-30/colistin combination can not only inhibit the formation of bacterial biofilm but also has a better eradication effect on preformed mature biofilms. The result of scanning electron microscopy (SEM) demonstrated that the furanone C-30/colistin combination led to a significant reduction in the number of cells in biofilms. Furthermore, furanone C-30 at 50 µg/ml did not cause any additional toxicity to RAW264.7 cells according to a cytotoxicity assay. In in vivo infection experiments, the furanone C-30/colistin combination increased the survival rate of infected Galleria mellonella larvae as well as decreased the microbial load in a mouse thigh infection model. The synergistic effect of the furanone C-30/colistin combination against colistin-resistant GNB is encouraging, and this work may shed light on a new therapeutic approach to combat colistin-resistant pathogens. IMPORTANCE Colistin is among the few antibiotics effective against multidrug-resistant Gram-negative bacteria (GNB) clinical isolates. However, colistin-resistant GNB strains have emerged in recent years. Therefore, the combination of colistin and nonantibacterial drugs has attracted much attention. In this study, the furanone C-30/colistin combination showed good antibacterial and antibiofilm activity in vitro and in vivo. In addition, increased membrane permeability leads to the synergistic effect of the furanone C-30/colistin combination. Because of the low cytotoxicity of furanone C-30, this combination has good application prospects in clinical anti-infective therapy. This finding might shed light on the discovery of combination therapy for infections caused by colistin-resistant GNB pathogens.

11.
Sci Total Environ ; : 151405, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780819

RESUMO

Since the existing satellite thermal infrared (TIR) land surface temperature (LST) is susceptible to cloud contamination and other factors, surface urban heat island (SUHI) studies based on TIR LST are limited to clear-sky conditions and are not representative of SUHI under all-weather conditions, which result in a possible clear-sky bias for SUHI. This study introduces a newly released 1-km all-weather LST product (TRIMS LST), which is spatiotemporally seamless, to investigate the real SUHI under all-weather conditions for five megacities (i.e. Harbin, Beijing, Shanghai, Guangzhou, and Chengdu) in China. Firstly, this study compares TRIMS SUHI with MODIS SUHI under clear-sky, partial-cloudy, and cloudy conditions. Secondly, the extent of the influence of cloudiness on SUHI is quantified. Finally, the monthly TRIMS SUHI is used to analyze the clear-sky bias that is caused by using only clear-sky data for the SUHI. Results indicate that (i) the absence of pixel data leads to negative offsets in the SUHI intensities calculated by MODIS LST, and these offsets expand gradually with increases in the number of missing-pixel data, causing the maximum offset to reach -1.83 °C under cloudy conditions in Chengdu; (ii) cloud can mitigate the SUHI for most cities: when the cloud coverage in Guangzhou reaches 90-100%, the daytime SUHI intensity decreases from 2.66 °C for clear-sky conditions to 1.70 °C; the mitigating effect differs at daytime and nighttime; and (iii) clear-sky bias varies significantly across climate zones and seasons, with a varying range of -1.6-1.2 °C for the five selected cities.

12.
Photodiagnosis Photodyn Ther ; : 102634, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34801775

RESUMO

BACKGROUND: Lesions in both the cervix and vagina require an efficacious non-invasive treatment therapy such as 5-Aminolevulinic acid photodynamic therapy(5-ALA-PDT). In this study, we evaluate clinical efficacy and safety of 5-ALA PDT for cervical intraepithelial neoplasia with vaginal intraepithelial neoplasia (CIN & VAIN). METHODS: A retrospective analysis was performed on 48 patients diagnosed with CIN & VAIN and receiving 5-ALA PDT. All patients were first followed up at 3, 6 and 12 months after treatment, then every 6 months thereafter. RESULTS: Out of 1051 patients referred for CIN (4.56%), 48 were diagnosed with CIN&VAIIN. The patients had statistically significant average vaginal and cervical lesion areas of 1.22 and 0.41 cm2 respectively. 4 patients were lost during follow-up. The patients' complete remission (CR) rate was 88.64% (39/44) at 3-6 months after treatment, while the total HPV clearance rate was 46.34 and 60.98% at 3- and 12-months follow-up,respectively. HPV16/18 combined with other high-risk human papillomaviruses (hrHPV) (HPV16/18 and other hrHPV) infection exhibited a lower HPV clearance rate (P=0.006). The treatment time in high-grade intraepithelial neoplasia (HSIL) was higher than that of low-grade intraepithelial neoplasia (LSIL). Notably, atypical vessels and endocervical canal lesions involvement significantly affected 5-ALA PDT. Moreover, 5 patients had residual lesions (11.36%) during follow-up, one patient presented recurrence (2.56%), while 4 had successful pregnancy. CONCLUSIONS: 5-ALA-PDT is a non-invasive, effective, and safe therapy for treating CIN & VAIN and can maintain the structural and functional integrity of target organs. However, its efficacy is relatively poor in patients with endocervical canal lesions involvement, atypical vessels, and HPV16/18 and other hrHPV infection.

13.
Artigo em Inglês | MEDLINE | ID: mdl-34802757

RESUMO

P-nitrophenol (PNP), a widely used compound, is harmful to the environment and human health. In this study, four iron-based Prussian blue analogs (PBAs) were prepared by coprecipitation (Co-Fe PBA, Mn-Fe PBA, Cu-Fe PBA and Fe-Fe PBA). The Co-Fe PBA exhibited high peroxymonosulfate (PMS) activation performance for PNP degradation, removing over 90% of PNP in 60 min at an optimal pH of 7, temperature at 30 ℃, initial concentration of 20 mg/L, PBA dose of 0.2 g/L and PMS dose of 1 g/L. The physicochemical properties of the Co-Fe PBA were investigated by various characterization methods. The catalytic activity of PBA and the influence of various process parameters and water quality on the catalytic reaction were investigated to elucidate the mechanism of p-nitrophenol degradation by PBA-activated persulfate. Moreover, the mechanism of accelerated degradation of PNP under HCO3- conditions and the role of major reactive oxides were determined by EPR measurement methods and free radical trapping experiments. HCO3- was found to directly activate PMS to produce reactive oxygen species, and 1O2, ∙OH and SO4∙- were all greatly increased. This work presents a promising green heterogeneous catalyst for the degradation of emerging contaminants (ECs) in real wastewater with natural organic matter and coexisting anions by PMS activation.

14.
J Hazard Mater ; : 127757, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34799163

RESUMO

The consumption of lithium-ion batteries raises raw material demand for and the pressure on ecological sustainability. Metals can be recovered in shorter paths while considerably boosting material use, hence selective recycling of specific elements is becoming a hotspot. This paper proposes a thermally-driven closed-loop recycling process for scrap LiNi1/3Co1/3Mn1/3O2 cathodes, in which Li is efficiently extracted by water leaching. Then, by combining the leaching residue with Li2CO3, a solid-phase synthesis is carried out, with Li being targeted to heal into Ni-Co-Mn-O to construct the layered structure. The electrochemical performance of the resynthesized cathode material is comparable to that of the commercial LiNi0.5Co0.2Mn0.3O2 (NCM523) material. During the thermal-driven conversion, solid-state processes can be observed. To ensure charge conservation, Li+ in the unstable layered structure is released and mixed with SO42- to produce Li2SO4, and lattice oxygen escapes and transforms with Ni2+ to generate NiO. For the resynthesized process, the spherical shape of Ni-Co-Mn-O is largely retained. Notably, sulfur is remained in the form of SO42- throughout the closed-loop process and is therefore free of contamination. The thermal-driven conversion recycling process revealed in this study will encourage researchers to ensure more efforts in efficient and selective recovery for sustainable energy storage of rechargeable batteries.

15.
Med Phys ; 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800037

RESUMO

PURPOSE: The main purpose of this work was to generate and validate the dosimetric accuracy of proton beams of dimensions that are appropriate for in vivo small animal and in vitro ultra-high dose rate (FLASH) radiotherapy experiments using a synchrotron-based treatment delivery system. This study was performed to enable future investigations of the relevance of a spread-out Bragg peak (SOBP) under FLASH conditions. METHODS: The spill characteristics of the small field fixed horizontal beam line were modified to deliver accelerated protons in times as short as 2 ms and to control the dose delivered. A Gaussian-like transverse beam profile was transformed into a square uniform one at FLASH dose rates, while avoiding low-dose regions, a crucial requirement to protect normal tissue during FLASH irradiation. Novel beam-shaping devices were designed using Monte Carlo techniques to produce up to about 6 cm3 of uniform dose in SOBPs while maximizing the dose rate. These included a scattering foil, a conical flattening filter to maximize the flux of protons into the region of interest, energy filters, range compensators, and collimators. The shapes, sizes, and positions of the components were varied to provide the required field sizes and SOBPs. RESULTS: The designed and fabricated devices were used to produce 10-, 15-, and 20-mm diameter, circular field sizes and 10-, 15-, and 20-mm SOBP modulation widths at uniform physical dose rates of up to 375 Gy/s at the center of the SOBP and a minimum dose rate of about 255 Gy/s at the entrance, respectively, in cylindrical volumes. The flatness of lateral dose profiles at the center could be adjusted to within ± 1.5% at the center of the SOBP. Assessment of systematic uncertainties, such as impact of misalignments and positioning uncertainties, was performed using simulations, and the results were used to provide appropriate adjustments to ensure high-accuracy FLASH beam delivery for both in vitro and in vivo preclinical experiments. CONCLUSIONS: It is feasible to use synchrotron-generated proton beams of sufficient dimensions for FLASH radiobiology experiments. We expect to use the system we developed to acquire in vitro and in vivo small animal FLASH radiobiology data as a function of dose, dose rate, oxygen content, and linear energy transfer to help us understand the underlying mechanisms of the FLASH phenomenon. This article is protected by copyright. All rights reserved.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34800270

RESUMO

A coupled g-C3N4/PDS system, named gCN-P, has been put forward to degrade refractory organic pollutants under simulated sunlight which integrates photocatalysis and PS-AOPs (advanced oxidation of persulfate based on sulfate radicals). The coupled g-C3N4 and PDS showed superior synergistic effect for MO degradation under simulated sunlight. Results showed that almost all MO was removed in the gCN-P system after irradiation for 80 min under simulated sunlight. The degradation rate of gCN-P system was improved by 12.6 and 4.9 times compared to single PDS and g-C3N4 systems, respectively. And only by adding 0.01 g of persulfate into the gCN-P system. The results of quenching experiments and EPR showed that O2-, 1O2 and h+ were main active species for the degradation of MO in the gCN-P system under simulated sunlight. Application of the gCN-P system in tap water samples demonstrated its excellent performance in real-world water environment, and the gCN-P system was employed for removing other new contaminants such as bisphenol A, ciprofloxacin, and paracetamol. The results demonstrated the gCN-P system can effectively remove organic pollutants under sunlight in practices.

17.
Gynecol Endocrinol ; : 1-7, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766534

RESUMO

OBJECTIVES: To evaluate the effectiveness of Growth hormone (GH) co-treatment during in vitro fertilization (IVF) cycles in women of different ages who manifest unexplained poor embryonic development. METHOD: This cohort study included a total of 2647 patients with unexplained poor embryonic development in their previous IVF procedures: 872 women received GH co-treatment and 1775 untreated women served as a control group. Patients were divided into 6 groups according to treatment and stratified by age (<35 years of age, A-GH group and A-control group; 35-40 years, B-GH group and B-control group; and ≥40 years, C-GH group and C-control group). The primary outcome was the oocyte-cleavage rate and the clinical pregnancy rate (CPR). RESULTS: The oocyte-cleavage rates among the three age groups were significantly higher in the GH group compared to the same-aged control group. In both group A and group B, there was no significant difference in clinical pregnancy rate between the GH group and controls. However, in patients ≥40 years of age, the clinical pregnancy rate in the GH group was significantly higher than in the control group (31.8% vs. 13.7%, p = 0.019). In the three age groups, there was no significant difference in the live birth rate between the GH group and controls. In the multivariate logistic regression analysis model, in both group A and group B, the number of cleaved embryos was independent predictors for CPR (OR = 1.464, 95% CI: 1.311-1.634; respectively, OR = 1.336, 95% CI: 1.126-1.586); Besides, in both group B and group C, age was independent predictors for CPR (OR = 0.657, 95%CI: 0.555-0.778; respectively, OR = 0.622, 95%CI: 0.391-0.989). However, only in group C, supplementation GH increased CPR as compared with not supplementation GH (OR = 2.339, 95%CI: 1.182-6.670). CONCLUSIONS: For patients with unexplained poor embryonic development, supplementation with GH increased the oocyte-cleavage rates in all three age groups, and the clinical pregnancy rate gradually improved commensurate with increasing age. There was no difference in the clinical pregnancy rate in group A and group B, but group C improved significantly. Therefore, compared with patients under 40 years of age, patients ≥40 may benefit more from GH supplementation.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34783135

RESUMO

Chemical fixation of carbon dioxide (CO 2 ) into value-added organics is regarded as a competitive and viable method in large scale industrial production, during which the catalysts with promoting CO 2 activation ability are needed. Herein, we proposed an in-plane heterostructure strategy to construct Lewis acid-base sites for efficient CO 2 activation. By taking ultrathin in-plane Cu 2 O/Cu heterostructures as a prototype, we show that Lewis acid-base sites on heterointerface can facilitate a mixed C and O dual coordination on surface, which not only strengthen CO 2 adsorption, but also effectively activate the inert molecules. As revealed by in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and quasi in-situ X-ray photoelectron spectroscopy (XPS), Lewis acid-base sites could readily activate CO 2 to •CO 2 - species, which is the key intermediate radical for CO 2 fixation. As a result, abundant Lewis acid-base sites endow Cu 2 O/Cu nanosheets with excellent performances for dimethyl carbonate generation, a high conversion yield of 28% with nearly 100% selectivity under mild conditions. This study provides a model structure for CO 2 fixation reactions.

19.
J Mater Chem B ; 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34797365

RESUMO

Neural electrodes are used for acquiring neuron signals in brain-machine interfaces, and they are crucial for next-generation neuron engineering and related medical applications. Thus, developing flexible, stable and high-resolution neural electrodes will play an important role in stimulation, acquisition, recording and analysis of signals. Compared with traditional metallic electrodes, electrodes based on graphene and other two-dimensional materials have attracted wide attention in electrophysiological recording and stimulation due to their excellent physical properties such as unique flexibility, low resistance, and high optical transparency. In this review, we have reviewed the recent progress of electrodes based on graphene, graphene/polymer compounds and graphene-related materials for neuron signal recording, stimulation, and related optical signal coupling technology, which provides an outlook on the role of electrodes in the nanotechnology-neuron interface as well as medical diagnosis.

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