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1.
Artigo em Inglês | MEDLINE | ID: mdl-35533008

RESUMO

Wearable integrated sensing devices with flexible electronic elements exhibit enormous potential in human-machine interfaces (HMI), but they have limitations such as complex structures, poor waterproofness, and electromagnetic interference. Herein, inspired by the profile of Lindernia nummularifolia (LN), a bionic stretchable optical strain (BSOS) sensor composed of an LN-shaped optical fiber incorporated with a stretchable substrate is developed for intelligent HMI. Such a sensor enables large strain and bending angle measurements with temperature self-compensation by the intensity difference of two fiber Bragg gratings' (FBGs') center wavelength. Such configurations enable an excellent tensile strain range of up to 80%, moreover, leading to ultrasensitivity, durability (≥20,000 cycles), and waterproofness. The sensor is also capable of measuring different human activities and achieving HMI control, including immersive virtual reality, robot remote interactive control, and personal hands-free communication. Combined with the machine learning technique, gesture classification can be achieved using muscle activity signals captured from the BSOS sensor, which can be employed to obtain the motion intention of the prosthetic. These merits effectively indicate its potential as a solution for medical care HMI and show promise in smart medical and rehabilitation medicine.

2.
Autophagy ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35543189

RESUMO

STING1 (stimulator of interferon response cGAMP interactor 1), the pivotal adaptor protein of cGAS (cyclic GMP-AMP synthase)-STING1 signaling, is critical for type I IFN production of innate immunity. However, excessive or prolonged activation of STING1 is associated with autoinflammatory and autoimmune diseases. Thus, preventing STING1 from over-activation is important to maintain immune homeostasis. Here, we reported that UXT (ubiquitously expressed prefoldin like chaperone), a small chaperone-like protein, was essential to prevent the excessive activation of STING1-mediated type I IFN signaling through autophagic degradation of STING1 via SQSTM1 (sequestosome 1). Upon DNA mimics or cyclic GMP-AMP (cGAMP) stimulation, UXT specifically interacted with STING1 and promoted STING1 degradation through selective macroautophagy/autophagy. Moreover, UXT was required for more efficient autophagic degradation of STING1 by facilitating the interaction of SQSTM1 and STING1. The in vivo role of UXT in attenuating the CGAS-STING1 signaling was further confirmed in the mouse model of DNA-virus infection and the TMPD (2,6,10,14-tetramethylpentadecane)-induced murine lupus model. Intriguingly, the expression of UXT was consistently impaired and exhibited a remarkable inverse correlation with type I IFN signature in the leukocytes and PBMCs (peripheral blood mononuclear cells) of several large SLE (systemic lupus erythematosus) cohorts. Importantly, the replenishment of UXT effectively suppressed the production of IFNs and ISGs in the PBMCs of SLE patients. Taken together, our study reveals a novel regulatory role of UXT in autophagic degradation of STING1 to maintain immune homeostasis. UXT might be a potential therapeutic target for alleviating aberrant type I IFNs in autoimmune diseases.

3.
Plant Methods ; 18(1): 62, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35546678

RESUMO

BACKGROUND: Rapid-cycling Brassica napus (B. napus-RC) has potential as a rapid trait testing system for canola (B. napus) because its life cycle is completed within 2 months while canola usually takes 4 months, and it is susceptible to the same range of diseases and abiotic stress as canola. However, a rapid trait testing system for canola requires the development of an efficient transformation and tissue culture system for B. napus-RC. Furthermore, effectiveness of this system needs to be demonstrated by showing that a particular trait can be rapidly introduced into B. napus-RC plants. RESULTS: An in-vitro regeneration protocol was developed for B. napus-RC using 4-day-old cotyledons as the explant. High regeneration percentages, exceeding 70%, were achieved when 1-naphthaleneacetic acid (0.10 mg/L), 6-benzylaminopurine (1.0 mg/L), gibberellic acid (0.01 mg/L) and the ethylene antagonist silver nitrate (5 mg/L) were included in the regeneration medium. An average transformation efficiency of 16.4% was obtained using Agrobacterium-mediated transformation of B. napus-RC cotyledons using Agrobacterium strain GV3101 harbouring a plasmid with an NPTII (kanamycin-selectable) marker gene and the Arabidopsis thaliana cDNA encoding ACYL-COA-BINDING PROTEIN6 (AtACBP6). Transgenic B. napus-RC overexpressing AtACBP6 displayed better tolerance to freezing/frost than the wild type, with enhanced recovery from cellular membrane damage at both vegetative and flowering stages. AtACBP6-overexpressing B. napus-RC plants also exhibited lower electrolyte leakage and improved recovery following frost treatment, resulting in higher yields than the wild type. Ovules from transgenic AtACBP6 lines were better protected from frost than those of the wild type, while the developing embryos of frost-treated AtACBP6-overexpressing plants showed less freezing injury than the wild type. CONCLUSIONS: This study demonstrates that B. napus-RC can be successfully regenerated and transformed from cotyledon explants and has the potential to be an effective trait testing platform for canola. Additionally, AtACBP6 shows potential for enhancing cold tolerance in canola however, larger scale studies will be required to further confirm this outcome.

4.
J Integr Plant Biol ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546447

RESUMO

Flowering time is a fundamental factor determining the global distribution and final yield of rice (Oryza sativa). Although diverse flowering time genes have been reported in this crop, the transcriptional regulation of its key flowering genes are poorly understood. Here, we report that a basic leucine zipper transcription factor, bZIP71, functions as a flowering repressor. The overexpression of bZIP71 delays flowering, while the bzip71 mutant flowers early in both long-day and short-day conditions. A genetic analysis showed that the regulation of flowering by bZIP71 might be independent of Heading date 2 (Hd2), Hd4, and Hd5. Importantly, bZIP71 directly associates with the Early heading date 1 (Ehd1) promoter and represses its transcription, and genetically the function of bZIP71 is impaired in the ehd1 mutant. Moreover, bZIP71 interacts with major components of polycomb repressive complex 2 (PRC2), SET domain group protein 711 (SDG711), and Fertilization independent endosperm 2 (FIE2), through which bZIP71 regulates the H3K27me3 level of Ehd1. Taken together, we present a transcriptional regulatory mechanism in which bZIP71 enhances the H3K27me3 level of Ehd1 and transcriptionally represses its expression, which not only offers a novel insight into a flowering pathway, but also provides a valuable putative target for the genetic engineering and breeding of elite rice cultivars. This article is protected by copyright. All rights reserved.

5.
Indian J Ophthalmol ; 70(5): 1736-1741, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35502063

RESUMO

Purpose: To evaluate changes in the levator palpebrae superioris (LPS) muscle on 3.0 T magnetic resonance imaging (MRI) after triamcinolone acetonide injection for treating upper lid retraction (ULR) with Graves' ophthalmopathy (GO) and to explore the value of LPS muscle quantitative measurement for clinical treatment. Methods: Patients with GO showing ULR were studied retrospectively and they underwent 3.0 T MRI scans before and after subconjunctival injection o f triamcinolone acetonide. The largest thickness (T) and highest signal intensity (SI) of LPS muscle on the affected eyes were measured in the sequences of coronal T2-weighted, fat-suppressed fast spin echo imaging (T2WI-fs) and T1-weighted, fat-suppressed, contrast-enhanced fast spin echo imaging (T1WI-fs + C), respectively. The SI ratio (SIR) (LPS muscle SI/ipsilateral temporalis SI) was calculated individually. Depending on the therapeutic effect, patients were divided into effective group and non-effective group. Independent t-test was used to compare SIR and T of LPS muscle in different treatment groups before treatment, and paired sample t-test was used to compare SIR and T of LPS muscle before and after treatment. Then cut-off level for predicting therapeutic effect and the receiver operating characteristic curve (ROC) curve were analyzed. Results: Sixty-two patients (77 eyes) were enrolled. After treatment, the T of LPS muscle showed significant decrease in all sequences in both effective and non-effective treatment groups. However, changes in SIR of LPS muscle in the two groups were different; SIR of LPS muscle on T2WI-fs and T1WI-fs + C decreased after treatment in the effective group (PT2 < 0.001, PT1 + C < 0.001) and SIR of LPS muscle showed no statistically difference in all sequences (all P > 0.05) in the non-effective group. There was a correlation between SIR of LPS muscle before treatment and after treatment with triamcinolone acetonide injection, which was that SIR of LPS muscle in the effective treatment group was lower than that in the non-effective treatment group on T1WI-fs + C (P < 0.001). SIR of LPS muscle on T1WI-fs + C showed 87.5% sensitivity and 66.7% specificity to predict therapeutic effect (area under the ROC curve [AUC] = 0.840). Conclusion: In GO patients with ULR, 3.0 T MRI can be used to evaluate the response of triamcinolone acetonide injection. SIR of LPS may be a predictor of its efficacy.


Assuntos
Doenças Palpebrais , Triancinolona Acetonida , Túnica Conjuntiva , Doenças Palpebrais/tratamento farmacológico , Humanos , Lipopolissacarídeos/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Transtornos da Visão
6.
Sheng Li Xue Bao ; 74(2): 145-154, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503062

RESUMO

The aim of this study was to investigate the harmful effects of acute hypoxia on mouse cerebral cortex and hippocampus and the underlying mechanism. Mouse model of acute hypoxia was constructed by using a sealed glass jar. Laser speckle contrast imaging was used to detect the changes of cerebral blood flow after different time duration of hypoxia. Total superoxide dismutase (T-SOD) and malondialdehyde (MDA) assay kits were used to detect oxidative stress in cerebral cortex and hippocampus. Immunofluorescent staining was used to detect neuroinflammatory response of microglia in the cerebral cortex and hippocampus. One-step TUNEL method was used to detect neuronal apoptosis. The results showed that, compared with non-hypoxia (0 min hypoxia) group, 30 min hypoxia group exhibited decreased cerebral blood flow, higher percentage of CD68+/Iba1+ microglia, and increased neural apoptosis in the cerebral cortex and hippocampus. Compared with 30 min group, 60 min hypoxia group showed significantly decreased cerebral blood flow, increased MDA content in the cortex, as well as greater percentage of CD68+/Iba1+ microglia and neuronal apoptosis in the cerebral cortex and hippocampus. These results suggest that acute hypoxia damages brain tissue in a time-dependent manner and the oxidative stress and neuroinflammation are important mechanisms.


Assuntos
Hipocampo , Hipóxia , Animais , Córtex Cerebral/metabolismo , Hipocampo/metabolismo , Malondialdeído , Camundongos , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia
7.
Sci Rep ; 12(1): 7380, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513480

RESUMO

Recently, low-concentration atropine (0.01%) has gained increased attention in controlling myopia progression with satisfying effects and minimal side effects. However, studies concerning responders to 0.01% atropine are limited. This retrospective observational cohort study aimed to determine the responder characteristics of 0.01% atropine in Asian children. One hundred forty children (aged between 3 and 15 years) receiving 0.01% atropine were analyzed for the factors influencing annual spherical equivalent changes (SE). The mean age was 9.13 (2.6) years, the mean baseline SE was - 1.56 (1.52) diopters (D), and the mean annual SE change was - 0.52 (0.49) D. A 58.63% responder rate (146/249) of myopic control was achieved with 0.01% atropine in our entire cohort under the criteria of less than 0.5 D of myopic progression annually. The subjects were stratified into 4 subgroups based on a cut-off point of baseline SE of - 1.5 D and baseline age of 9 years. The responder rate differed significantly with the highest being the youngest with the lowest myopia subgroups. Our results demonstrated that children with myopia better than - 1.5 D and younger than 9 years had the highest potential to achieve successful myopic control under 0.01% atropine therapy.


Assuntos
Atropina , Miopia , Adolescente , Criança , Pré-Escolar , Progressão da Doença , Humanos , Midriáticos , Miopia/tratamento farmacológico , Soluções Oftálmicas/uso terapêutico , Refração Ocular , Estudos Retrospectivos
8.
Commun Biol ; 5(1): 436, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538218

RESUMO

Glioblastomas remain the most lethal primary brain tumors. Natural killer (NK) cell-based therapy is a promising immunotherapeutic strategy in the treatment of glioblastomas, since these cells can select and lyse therapy-resistant glioblastoma stem-like cells (GSLCs). Immunotherapy with super-charged NK cells has a potential as antitumor approach since we found their efficiency to kill patient-derived GSLCs in 2D and 3D models, potentially reversing the immunosuppression also seen in the patients. In addition to their potent cytotoxicity, NK cells secrete IFN-γ, upregulate GSLC surface expression of CD54 and MHC class I and increase sensitivity of GSLCs to chemotherapeutic drugs. Moreover, NK cell localization in peri-vascular regions in glioblastoma tissues and their close contact with GSLCs in tumorospheres suggests their ability to infiltrate glioblastoma tumors and target GSLCs. Due to GSLC heterogeneity and plasticity in regards to their stage of differentiation personalized immunotherapeutic strategies should be designed to effectively target glioblastomas.


Assuntos
Glioblastoma , Diferenciação Celular , Glioblastoma/metabolismo , Glioblastoma/terapia , Humanos , Imunoterapia Adotiva , Células Matadoras Naturais , Células-Tronco Neoplásicas
9.
Adv Sci (Weinh) ; : e2200986, 2022 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-35434937

RESUMO

Cholestatic drug-induced liver injury (DILI) induced by drugs or other xenobiotics is a severe and even fatal clinical syndrome. Here, living materials of hierarchy-assembled dual probiotics system are fabricated by sequentially encapsulating probiotic Lactobacillus delbrueckii subsp. bulgaricus (LDB) and Lactobacillus rhamnosus GG (LGG) into Ca2+ -complexed polymer microspheres for effective prevention of cholestatic DILI. Upon entering intestinal tract of the constructed living materials, LGG is released because of pH-triggered dissolution of outer enteric polymer coating. The released LGG can inhibit hepatic bile acids (BAs) synthesis by activating intestinal farnesoid X receptor-fibroblast growth factor 15(FGF-15) signaling pathway. BAs excretion is also facilitated by LGG through increasing the abundance of bile salt hydrolase (BSH)-active gut commensal bacteria. Furthermore, exposed positively-charged chitosan shell can absorb the excessive BAs via electrostatic interaction, which leads to steady BAs fixation by the imprisoned LDB, decreasing the total BAs amounts in enterohepatic circulation. Together, the fabricated living materials, obtained here, can effectively prevent cholestatic DILI through dredging cholestasis via gut-liver axis modulation. The therapeutic effect is demonstrated in α-naphthylisothiocyanate and clinical antiepileptic drug valproate acid-induced cholestatic DILI mouse models, which reveal the great potential for effective cholestatic DILI management.

10.
Chem Commun (Camb) ; 58(33): 5100-5103, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35388834

RESUMO

A perylene five-membered ring diimide, PDI39, was developed as a new electron-deficient building block for n-type semiconductors. The π-expanded conjugated molecules containing azulenes were synthesized from PDI39. These conjugated molecules show helical geometry and near-infrared absorption up to 810 nm.

11.
Bioengineered ; 13(4): 11122-11136, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35481488

RESUMO

Alcoholic liver disease (ALD), with its increasing morbidity and mortality, has seriously and extensively affected the health of people worldwide. Caffeic Acid Dimethyl Ether (CADE) significantly inhibits alcohol-induced hepatic steatosis in vivo through AMP-activated protein kinase (AMPK) pathway, but its in-depth mechanism remains unclear. This work aimed to clarify further mechanism of CADE in improving hepatic lipid accumulation in ALD through the microRNA-378b (miR-378b)-mediated Ca2+/calmodulin-dependent protein kinase kinase 2 (CaMKK2)-AMPK signaling pathway. Here, we reported that the hepatic or serum triglyceride (TG), total cholesterol (TC), alanine aminotransferase (ALT), and aspartate transaminase (AST) levels were sharply escalated by ethanol while prominently decreased by CADE. Ethanol sharply up-regulated miR-378b expression while CADE effectively prevented the elevation of miR-378b in vivo. And treatment of CADE surely increased mRNA and protein expression of CaMKK2 as a kinase of AMPK and reduced lipid accumulation in the livers of alcohol-fed C57BL/6 mice. MiR-378b escalation exacerbated hepatic steatosis and inhibited CaMKK2-AMPK signaling, while miR-378b deficiency alleviated lipid accumulation and activated the CaMKK2 cascade. Furthermore, CADE alleviated the lipid deposition and reversed the disorder of CaMKK2-AMPK signaling pathway induced by miR-378b over-expression. However, knockdown of miR-378b eliminated the beneficial effect of CADE on lipid metabolism. In brief, our results showed that CADE ultimately improved hepatic lipid deposition by regulating the CaMKK2-AMPK signaling pathway through miR-378b.


Assuntos
Proteínas Quinases Ativadas por AMP , MicroRNAs , Proteínas Quinases Ativadas por AMP/genética , Animais , Ácidos Cafeicos , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/genética , Etanol/toxicidade , Humanos , Lipídeos , Éteres Metílicos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo
12.
Front Cardiovasc Med ; 9: 823436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35391847

RESUMO

Motivation: Retinal microvasculature is a unique window for predicting and monitoring major cardiovascular diseases, but high throughput tools based on deep learning for in-detail retinal vessel analysis are lacking. As such, we aim to develop and validate an artificial intelligence system (Retina-based Microvascular Health Assessment System, RMHAS) for fully automated vessel segmentation and quantification of the retinal microvasculature. Results: RMHAS achieved good segmentation accuracy across datasets with diverse eye conditions and image resolutions, having AUCs of 0.91, 0.88, 0.95, 0.93, 0.97, 0.95, 0.94 for artery segmentation and 0.92, 0.90, 0.96, 0.95, 0.97, 0.95, 0.96 for vein segmentation on the AV-WIDE, AVRDB, HRF, IOSTAR, LES-AV, RITE, and our internal datasets. Agreement and repeatability analysis supported the robustness of the algorithm. For vessel analysis in quantity, less than 2 s were needed to complete all required analysis.

13.
Front Cardiovasc Med ; 9: 794925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419440

RESUMO

Background: Currently, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) are commonly used in the treatment of coronary atherosclerotic heart disease. But the optimal timing for CABG after acute myocardial infarction (AMI) is still controversial. The purpose of this article was to evaluate the optimal timing for CABG in AMI. Methods: We searched the PubMed, Embase, and Cochrane library databases for documents that met the requirements. The primary outcome was in-hospital mortality. The secondary outcomes were perioperative myocardial infarction (MI) incidence and cerebrovascular accident incidence. Results: The search strategy produced 1,742 studies, of which 19 studies (including data from 113,984 participants) were included in our analysis. In total, 14 studies compared CABG within 24 h with CABG late 24 h after AMI and five studies compared CABG within 48 h with CABG late 48 h after AMI. The OR of in-hospital mortality between early 24 h CABG and late 24 h CABG group was 2.65 (95%CI: 1.96 to 3.58; P < 0.00001). In the undefined ST segment elevation myocardial infarction (STEMI)/non-ST segment elevation myocardial infarction (NSTEMI) subgroup, the mortality in the early 24 h CABG group (OR: 3.88; 95%CI: 2.69 to 5.60; P < 0.00001) was significantly higher than the late 24 h CABG group. Similarly, in the STEMI subgroup, the mortality in the early 24 h CABG group (OR: 2.62; 95% CI: 1.58 to 4.35; P = 0.0002) was significantly higher than that in the late 24 h CABG group. However, the mortality of the early 24 h CABG group (OR: 1.24; 95%CI: 0.83 to 1.85; P = 0.29) was not significantly different from that of the late 24 h CABG group in the NSTEMI group. The OR of in-hospital mortality between early 48 h CABG and late 48 h CABG group was 1.91 (95%CI: 1.11 to 3.29; P = 0.02). In the undefined STEMI/NSTEMI subgroup, the mortality in the early 48 h CABG group (OR: 2.84; 95%CI: 1.31 to 6.14; P < 0.00001) was higher than the late 48 h CABG group. The OR of perioperative MI and cerebrovascular accident between early CABG and late CABG group were 1.38 (95%CI: 0.41 to 4.72; P = 0.60) and 1.31 (95%CI: 0.72 to 2.39; P = 0.38), respectively. Conclusion: The risk of early CABG could be higher in STEMI patients, and CABG should be delayed until 24 h later as far as possible. However, the timing of CABG does not affect mortality in NSTEMI patients. There was no statistical difference in perioperative MI and cerebrovascular accidents between early and late CABG.

14.
Pharmacol Res ; 179: 106198, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367343

RESUMO

Despite recent advances in diagnosis and therapeutic strategies, treatment of non-small-cell lung cancer (NSCLC) remains unsatisfactory in terms of prognosis. Andrographolide (AD), a principal active component of Andrographis paniculata (Burm.f.) Nees, exerts anti-cancer therapeutic properties. AD has been used for centuries in China for clinical treatment of viral infections. However, the pharmacological biology of AD in NSCLC remains unknown. In this study, AD regulated autophagy and PD-L1 expression in NSCLC. Molecular dynamics simulations indicated that AD bound directly to signal transducer and activator of transcription-3 (STAT3) with high affinity. Proteomics analysis indicated that AD reduced the expression of tumour PD-L1 in NSCLC by suppressing JAK2/STAT3 signalling. AD modulated the P62-dependent selective autophagic degradation of PD-L1 by inhibiting STAT3 phosphorylation. In vivo study revealed that AD suppressed tumour growth in H1975 xenograft mice and Lewis lung carcinoma cell models, and better efficacy was obtained at higher concentrations. AD prolonged the survival time of the mice and enhanced the treatment efficacy of anti-PD-1 mAb immunotherapy by stimulating CD8+ T cell infiltration and function. This work elucidated the specific mechanism by which AD inhibited NSCLC. Treatment with the combination of AD and anti-PD-1 mAb immunotherapy could be a potential strategy for patients with NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Autofagia , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Diterpenos , Humanos , Imunidade , Neoplasias Pulmonares/metabolismo , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Tradit Chin Med ; 42(2): 314-320, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35473354

RESUMO

Chronic respiratory diseases (CRDs) are among the most common noncommunicable diseases globally, with high morbidity and mortality rates. Acupuncture, a treatment method derived from Traditional Chinese Medicine, has been shown to be effective at treating CRDs, with little risk of adverse effects. Scientific research on the mechanisms underlying the effects of acupuncture, especially, its immune regulatory function, has rapidly advanced in recent years. Herein, the diverse immune regulatory mechanisms underlying the beneficial effects of acupuncture are summarized from the perspectives of innate immunity, adaptive immunity, and neuroimmunity. A better understanding of these mechanisms will ultimately provide a scientific basis for the clinical use of acupuncture for the treatment of CRDs.


Assuntos
Terapia por Acupuntura , Humanos , Medicina Tradicional Chinesa
16.
Front Oncol ; 12: 830981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35449577

RESUMO

Purpose: This study aimed to quantitatively evaluate the range uncertainties that arise from daily cone-beam CT (CBCT) images for proton dose calculation compared to CT using a measurement-based technique. Methods: For head and thorax phantoms, wedge-shaped intensity-modulated proton therapy (IMPT) treatment plans were created such that the gradient of the wedge intersected and was measured with a 2D ion chamber array. The measured 2D dose distributions were compared with 2D dose planes extracted from the dose distributions using the IMPT plan calculated on CT and CBCT. Treatment plans of a thymoma cancer patient treated with breath-hold (BH) IMPT were recalculated on 28 CBCTs and 9 CTs, and the resulting dose distributions were compared. Results: The range uncertainties for the head phantom were determined to be 1.2% with CBCT, compared to 0.5% for CT, whereas the range uncertainties for the thorax phantom were 2.1% with CBCT, compared to 0.8% for CT. The doses calculated on CBCT and CT were similar with similar anatomy changes. For the thymoma patient, the primary source of anatomy change was the BH uncertainty, which could be up to 8 mm in the superior-inferior (SI) direction. Conclusion: We developed a measurement-based range uncertainty evaluation method with high sensitivity and used it to validate the accuracy of CBCT-based range and dose calculation. Our study demonstrated that the CBCT-based dose calculation could be used for daily dose validation in selected proton patients.

17.
ACS Omega ; 7(13): 11371-11381, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35415365

RESUMO

A novel two-dimensional α-Fe2O3/sulfur-doped polyimide (FO/SPI) direct Z-scheme photocatalyst was successfully constructed by a facile thermal treatment method. The effects of α-Fe2O3 nanosheets on the morphology, chemical structure, and photoelectronic properties of FO/SPI composites were systematically characterized by different spectroscopic means. These methods include X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, transient fluorescence spectra, and so forth. It was confirmed that the small amounts of α-Fe2O3 can availably facilitate exfoliation of bulk SPI, resulting in a transformation of SPI from bulk to 2D layered composite that illustrates tight interface through the coordination Fe-N bond and an all-solid-state direct Z-scheme junction. Thus, the transfer and separation efficiency of photogenerated electron/hole pairs were significantly enhanced, which greatly promoted improvement of the photocatalytic activity of the FO/SPI composite for methyl orange degradation under solar light. This work provides a new approach to constructing efficient inorganic-organic Z-scheme photocatalyst based on strong interface interaction.

18.
Artigo em Inglês | MEDLINE | ID: mdl-35270289

RESUMO

In this study, fixed-bed adsorption of Pb(II) from an aqueous solution using chitosan-coated bentonite (CCB) was investigated. Characterization of CCB was performed using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The effects of varying bed height (1.3 to 4.3 cm), flow rate (0.20 to 0.60 mL/min), and initial concentration (500 to 1500 mg/L) on the length of mass transfer zone (Zm) and adsorption capacity at breakthrough (qb) and exhaustion (qe) were examined. Low flow rate and high bed height were determined to cause a longer time to reach breakthrough and exhaustion. Meanwhile, the fixed-bed system was observed to quickly attain breakthrough and exhaustion under high initial concentrations. Kinetic column models such as the Thomas, Yoon-Nelson, and Clark models were used to predict the breakthrough curves. High R2 values (0.9758 ≤ R2 ≤ 0.8087) were attained for the Thomas model, which indicates that there is good agreement between experimental data and linear plots generated by the Thomas model. Moreover, the Thomas model is best in describing the breakthrough curves of Pb(II) removal under a fixed-bed system.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Adsorção , Bentonita , Quitosana/química , Chumbo , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
19.
BMC Cardiovasc Disord ; 22(1): 103, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287572

RESUMO

BACKGROUND: Calcified plaque is thought to adversely impact outcomes after percutaneous coronary intervention (PCI). This study sought to evaluate the impact of nodular calcification in patients with acute coronary syndrome treated with primary percutaneous coronary intervention. METHODS: Using optical coherence tomography (OCT), 500 culprit plaques with calcification were analyzed from 495 acute coronary syndrome (ACS) patients on whom PCI was performed. Based on morphology, we classified calcification into two subtypes: nodular calcification and non-nodular calcification. Nodular calcification was defined as protruding mass with an irregular surface, high backscattering, and signal attenuation while non-nodular calcification was defined as an area with low backscattering heterogeneous region with a well-delineated border without protrusion into the lumen on OCT. RESULTS: Calcified culprit plaques were divided into nodular calcification group (n = 238) and non-nodular calcification group (n = 262). Patients with nodular calcification were older (p < 0.001) and had lower left ventricular ejection fraction (p = 0.006) compared to patients with non-nodular calcification. Minimum stent area (5.0 (3.9, 6.3) mm2 vs. 5.4 (4.2, 6.7) mm2, p = 0.011) and stent expansion (70 (62.7, 81.8) % vs. 75 (65.2, 86.6) %, p = 0.004) were significantly smaller in the nodular calcification group than in the non-nodular calcification group. Stent under-expansion was most frequent (p = 0.003) in the nodular calcification group. CONCLUSION: This study demonstrate that the presence of nodular calcification is associated with a smaller minimum stent area and a higher incidence of stent under-expansion. Lesions with nodular calcification may be at risk of stent under-expansion.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Placa Aterosclerótica , Calcificação Vascular , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/terapia , Angiografia Coronária/métodos , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Stents , Volume Sistólico , Tomografia de Coerência Óptica/métodos , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Calcificação Vascular/terapia , Função Ventricular Esquerda
20.
Cell Rep ; 38(11): 110529, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35294871

RESUMO

De-etiolation is indispensable for seedling survival and development. However, how sugars regulate de-etiolation and how sugars induce ethylene (ET) for seedlings to grow out of soil remain elusive. Here, we reveal how a sucrose (Suc) feedback loop promotes de-etiolation by inducing ET biosynthesis. Under darkness, Suc in germinating seeds preferentially induces 1-amino-cyclopropane-1-carboxylate synthase (ACS7; encoding a key ET biosynthesis enzyme) and associated ET biosynthesis, thereby activating ET core component ETHYLENE-INSENSITIVE3 (EIN3). Activated EIN3 directly inhibits the function of Suc transporter 2 (SUC2; a major Suc transporter) to block Suc export from cotyledons and thereby elevate Suc accumulation of cotyledons to induce ET. Under light, ET-activated EIN3 directly inhibits the function of phytochrome A (phyA; a de-etiolation inhibitor) to promote de-etiolation. We therefore propose that under darkness, the Suc feedback loop (Suc-ACS7-EIN3-|SUC2-Suc) promotes Suc accumulation in cotyledons to guarantee ET biosynthesis, facilitate de-etiolation, and enable seedlings to grow out of soil.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cotilédone/metabolismo , Etilenos , Retroalimentação , Regulação da Expressão Gênica de Plantas , Luz , Plântula/metabolismo , Solo , Sacarose , Açúcares
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