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1.
Int J Chron Obstruct Pulmon Dis ; 19: 1591-1601, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005647

RESUMO

Background: Exercise is an indispensable component of pulmonary rehabilitation with strong anti-inflammatory effects. However, the mechanisms by which exercise prevents diaphragmatic atrophy in COPD (chronic obstructive pulmonary disease) remain unclear. Methods: Forty male C57BL/6 mice were assigned to the control (n=16) and smoke (n=24) groups. Mice in the smoke group were exposed to the cigarette smoke (CS) for six months. They were then divided into model and exercise training groups for 2 months. Histological changes were observed in lung and diaphragms. Subsequently, agonist U46639 and antagonist Y27632 of RhoA/ROCK were subjected to mechanical stretching in LPS-treated C2C12 myoblasts. The expression levels of Atrogin-1, MuRF-1, MyoD, Myf5, IL-1ß, TNF-α, and RhoA/ROCK were determined by Western blotting. Results: Diaphragmatic atrophy and increased RhoA/ROCK expression were observed in COPD mice. Exercise training attenuated diaphragmatic atrophy, decreased the expression of MuRF-1, and increased MyoD expression in COPD diaphragms. Exercise also affects the upregulation of RhoA/ROCK and inflammation-related proteins. In in vitro experiments with C2C12 myoblasts, LPS remarkably increased the level of inflammation and protein degradation, whereas Y27632 or combined with mechanical stretching prevented this phenomenon considerably. Conclusion: RhoA/ROCK plays an important role in the prevention of diaphragmatic atrophy in COPD.


Assuntos
Diafragma , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Atrofia Muscular , Doença Pulmonar Obstrutiva Crônica , Transdução de Sinais , Quinases Associadas a rho , Proteína rhoA de Ligação ao GTP , Animais , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Quinases Associadas a rho/metabolismo , Masculino , Atrofia Muscular/prevenção & controle , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Atrofia Muscular/fisiopatologia , Atrofia Muscular/etiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Diafragma/metabolismo , Diafragma/fisiopatologia , Diafragma/patologia , Linhagem Celular , Proteínas rho de Ligação ao GTP/metabolismo , Terapia por Exercício/métodos , Camundongos , Pulmão/patologia , Pulmão/metabolismo , Pulmão/fisiopatologia , Mediadores da Inflamação/metabolismo , Condicionamento Físico Animal
2.
Small ; : e2404741, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031679

RESUMO

Catalytic therapy has shown great potential for clinical application. However, conventional catalytic therapies rely on reactive oxygen species (ROS) as "therapeutic drugs," which have limitations in effectively inhibiting tumor recurrence and metastasis. Here, a biomimetic heterojunction catalyst is developed that can actively target orthotopic rectal cancer after oral administration. The heterojunction catalyst is composed of quatrefoil star-shaped BiVO4 (BVO) and ZnIn2S4 (ZIS) nanosheets through an in situ direct growth technique. Poly-norepinephrine and macrophage membrane coatings afford the biomimetic heterojunction catalyst (BVO/ZIS@M), which has high rectal cancer targeting and retention abilities. The coupled optical fiber intervention technology activates the multicenter coordination of five catalytic reactions of heterojunction catalysts, including two reduction reactions (O2→·O2 - and CO2→CO) and three oxidation reactions (H2O→·OH, GSH→GSSG, and LA→PA). These catalytic reactions not only induce immunogenic death in tumor cells through the efficient generation of ROS/CO and the consumption of GSH but also specifically lead to the use of lactic acid (LA) as an electron donor to improve catalytic activity and disrupt the LA-mediated immunosuppressive microenvironment, mediating synergistic catalysis and immunotherapy for orthotopic rectal cancer. Therefore, this optical fiber intervention triggered the combination of heterojunction catalytic therapy and immunotherapy, which exhibits prominent antitumor effects.

3.
Biotechnol Adv ; 73: 108374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38729229

RESUMO

Indigo is a natural dye extensively used in the global textile industry. However, the conventional synthesis of indigo using toxic compounds like aniline, formaldehyde, and hydrogen cyanide has led to environmental pollution and health risks for workers. This method also faces growing economic, sustainability, and environmental challenges. To address these issues, the concept of bio-indigo or indigo biosynthesis has been proposed as an alternative to aniline-based indigo synthesis. Among various enzymes, Flavin-containing Monooxygenases (FMOs) have shown promise in achieving a high yield of bio-indigo. However, the industrialization of indigo biosynthesis still encounters several challenges. This review focuses on the historical development of indigo biosynthesis mediated by FMOs. It highlights several factors that have hindered industrialization, including the use of unsuitable chassis (Escherichia coli), the toxicity of indole, the high cost of the substrate L-tryptophan, the water-insolubility of the product indigo, the requirement of reducing reagents such as sodium dithionite, and the relatively low yield and high cost compared to chemical synthesis. Additionally, this paper summarizes various strategies to enhance the yield of indigo synthesized by FMOs, including redundant sequence deletion, semi-rational design, cheap precursor research, NADPH regeneration, large-scale fermentation, and enhancement of water solubility of indigo.


Assuntos
Índigo Carmim , Índigo Carmim/metabolismo , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/genética , Oxigenases/metabolismo , Oxigenases/genética , Corantes/química , Corantes/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
4.
Sci Adv ; 10(19): eadm9561, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38718119

RESUMO

Lactic acid (LA) accumulation in the tumor microenvironment poses notable challenges to effective tumor immunotherapy. Here, an intelligent tumor treatment microrobot based on the unique physiological structure and metabolic characteristics of Veillonella atypica (VA) is proposed by loading Staphylococcus aureus cell membrane-coating BaTiO3 nanocubes (SAM@BTO) on the surface of VA cells (VA-SAM@BTO) via click chemical reaction. Following oral administration, VA-SAM@BTO accurately targeted orthotopic colorectal cancer through inflammatory targeting of SAM and hypoxic targeting of VA. Under in vitro ultrasonic stimulation, BTO catalyzed two reduction reactions (O2 → •O2- and CO2 → CO) and three oxidation reactions (H2O → •OH, GSH → GSSG, and LA → PA) simultaneously, effectively inducing immunogenic death of tumor cells. BTO catalyzed the oxidative coupling of VA cells metabolized LA, effectively disrupting the immunosuppressive microenvironment, improving dendritic cell maturation and macrophage M1 polarization, and increasing effector T cell proportions while decreasing regulatory T cell numbers, which facilitates synergetic catalysis and immunotherapy.


Assuntos
Compostos de Bário , Materiais Biomiméticos , Neoplasias Colorretais , Terapia de Imunossupressão , Nanotubos , Robótica , Titânio , Microambiente Tumoral , Veillonella , Materiais Biomiméticos/administração & dosagem , Catálise , Neoplasias Colorretais/tratamento farmacológico , Staphylococcus aureus , Nanotubos/química , Titânio/administração & dosagem , Titânio/farmacologia , Compostos de Bário/administração & dosagem , Compostos de Bário/farmacologia , Membrana Celular/química , Administração Oral , Oxirredução , Terapia de Imunossupressão/métodos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Ácido Láctico/metabolismo , Humanos , Linhagem Celular Tumoral
5.
Adv Sci (Weinh) ; 11(22): e2310211, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460166

RESUMO

The precise targeted delivery of therapeutic agents to deep regions of the brain is crucial for the effective treatment of various neurological diseases. However, achieving this goal is challenging due to the presence of the blood‒brain barrier (BBB) and the complex anatomy of the brain. Here, a biomimetic self-propelled nanomotor with cascade targeting capacity is developed for the treatment of neurological inflammatory diseases. The self-propelled nanomotors are designed with biomimetic asymmetric structures with a mesoporous SiO2 head and multiple MnO2 tentacles. Macrophage membrane biomimetic modification endows nanomotors with inflammatory targeting and BBB penetration abilities The MnO2 agents catalyze the degradation of H2O2 into O2, not only by reducing brain inflammation but also by providing the driving force for deep brain penetration. Additionally, the mesoporous SiO2 head is loaded with curcumin, which actively regulates macrophage polarization from the M1 to the M2 phenotype. All in vitro cell, organoid model, and in vivo animal experiments confirmed the effectiveness of the biomimetic self-propelled nanomotors in precise targeting, deep brain penetration, anti-inflammatory, and nervous system function maintenance. Therefore, this study introduces a platform of biomimetic self-propelled nanomotors with inflammation targeting ability and active deep penetration for the treatment of neurological inflammation diseases.


Assuntos
Biomimética , Barreira Hematoencefálica , Dióxido de Silício , Animais , Dióxido de Silício/química , Camundongos , Biomimética/métodos , Barreira Hematoencefálica/metabolismo , Compostos de Manganês/química , Materiais Biomiméticos/química , Sistemas de Liberação de Medicamentos/métodos , Óxidos/química , Curcumina/uso terapêutico , Curcumina/farmacologia , Modelos Animais de Doenças , Doenças Neuroinflamatórias , Inflamação , Macrófagos , Encéfalo/metabolismo , Nanopartículas/química
6.
Adv Mater ; 36(24): e2312008, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38501999

RESUMO

Antiferromagnetic (AFM) materials are a pathway to spintronic memory and computing devices with unprecedented speed, energy efficiency, and bit density. Realizing this potential requires AFM devices with simultaneous electrical writing and reading of information, which are also compatible with established silicon-based manufacturing. Recent experiments have shown tunneling magnetoresistance (TMR) readout in epitaxial AFM tunnel junctions. However, these TMR structures are not grown using a silicon-compatible deposition process, and controlling their AFM order required external magnetic fields. Here are shown three-terminal AFM tunnel junctions based on the noncollinear antiferromagnet PtMn3, sputter-deposited on silicon. The devices simultaneously exhibit electrical switching using electric currents, and electrical readout by a large room-temperature TMR effect. First-principles calculations explain the TMR in terms of the momentum-resolved spin-dependent tunneling conduction in tunnel junctions with noncollinear AFM electrodes.

7.
Microbiol Res ; 282: 127629, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330819

RESUMO

Apart from its role in translation, codon bias is also an important mechanism to regulate mRNA levels. The traditional frequency-based codon optimization strategy is rather efficient in organisms such as N. crassa, but much less in yeast P. pastoris which is a popular host for heterologous protein expression. This is because that unlike N. crassa, the preferred codons of P. pastoris are actually AU-rich and hence codon optimization for extremely low GC content comes with issues of pre-mature transcriptional termination or low RNA stability in spite of translational advantages. To overcome this bottleneck, we focused on three reporter genes in P. pastoris first and confirmed the great advantage of GC-prone codon optimization on mRNA levels. Then we altered the codon bias profile of P. pastoris by introducing additional rare tRNA gene copies. Prior to that we constructed IPTG-regulated tRNA species to enable chassis cells to switch between different codon bias status. As demonstrated again with reporter genes, protein yield of luc and 0788 was successfully increased by 4-5 folds in chassis cells. In summary, here we provide an alternative codon optimization strategy for genes with unsatisfactory performance under traditional codon frequency-based optimization.


Assuntos
Uso do Códon , Pichia , Pichia/genética , Códon/genética , RNA Mensageiro/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Proteínas Recombinantes/genética
8.
Clin Transl Oncol ; 26(2): 496-514, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37407805

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common types of malignant tumors, with a slow onset, rapid progression, and frequent recurrence. Previous research has implicated mitochondrial ribosomal genes in the development, metastasis, and prognosis of various cancers. However, further research is necessary to establish a link between mitochondrial ribosomal protein (MRP) family expression and HCC diagnosis, prognosis, ferroptosis-related gene (FRG) expression, m6A modification-related gene expression, tumor immunity, and drug sensitivity. METHODS: Bioinformatics resources were used to analyze data from patients with HCC retrieved from the TCGA, ICGC, and GTEx databases (GEPIA, UALCAN, Xiantao tool, cBioPortal, STRING, Cytoscape, TISIDB, and GSCALite). RESULTS: Among the 82 MRP family members, 14 MRP genes (MRPS21, MRPS23, MRPL9, DAP3, MRPL13, MRPL17, MRPL24, MRPL55, MRPL16, MRPL14, MRPS17, MRPL47, MRPL21, and MRPL15) were significantly upregulated differentially expressed genes (DEGs) in HCC tumor samples in comparison to normal samples. Receiver-operating characteristic curve analysis indicated that all 14 DEGs show good diagnostic performance. Furthermore, TCGA analysis revealed that the mRNA expression of 39 MRPs was associated with overall survival (OS) in HCC. HCC was divided into two molecular subtypes (C1 and C2) with distinct prognoses using clustering analysis. The clusters showed different FRG expression and m6A methylation profiles and immune features, and prognostic models showed that the model integrating 5 MRP genes (MRPS15, MRPL3, MRPL9, MRPL36, and MRPL37) and 2 FRGs (SLC1A5 and SLC5A11) attained a greater clinical net benefit than three other prognostic models. Finally, analysis of the CTRP and GDSC databases revealed several potential drugs that could target prognostic MRP genes. CONCLUSION: We identified 14 MRP genes as HCC diagnostic markers. We investigated FRG and m6A modification-related gene expression profiles and immune features in patients with HCC, and developed and validated a model incorporating MRP and FRG expression that accurately and reliably predicts HCC prognosis and may predict disease progression and treatment response.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Prognóstico , Ribossomos , Proteínas Ribossômicas/genética , Biomarcadores Tumorais/genética , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos , Proteínas de Transporte de Sódio-Glucose
9.
Adv Mater ; 36(3): e2308726, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37842855

RESUMO

Piezoelectric, pyroelectric, and ferroelectric materials are considered unique biomedical materials due to their dielectric crystals and asymmetric centers that allow them to directly convert various primary forms of energy in the environment, such as sunlight, mechanical energy, and thermal energy, into secondary energy, such as electricity and chemical energy. These materials possess exceptional energy conversion ability and excellent catalytic properties, which have led to their widespread usage within biomedical fields. Numerous biomedical applications have demonstrated great potential with these materials, including disease treatment, biosensors, and tissue engineering. For example, piezoelectric materials are used to stimulate cell growth in bone regeneration, while pyroelectric materials are applied in skin cancer detection and imaging. Ferroelectric materials have even found use in neural implants that record and stimulate electrical activity in the brain. This paper reviews the relationship between ferroelectric, piezoelectric, and pyroelectric effects and the fundamental principles of different catalytic reactions. It also highlights the preparation methods of these three materials and the significant progress made in their biomedical applications. The review concludes by presenting key challenges and future prospects for efficient catalysts based on piezoelectric, pyroelectric, and ferroelectric nanomaterials for biomedical applications.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Materiais Biocompatíveis/farmacologia , Encéfalo , Catálise , Proliferação de Células
10.
BMC Complement Med Ther ; 23(1): 418, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985995

RESUMO

BACKGROUND: Physical exercise training is the central component of pulmonary rehabilitation. This study aimed to further investigate the rehabilitative effects of pulmonary-based Qigong exercise (PQE) in stable patients with chronic obstructive pulmonary disease (COPD). METHODS: In this randomized, assessor-blinded clinical trial, 44 participants with stable COPD were randomly assigned to 2 groups in a 1:1 ratio. Participants in the control group received usual care for 3 months. Participants in the intervention group received usual care combined with PQE (60 min each time, 2 times per day, 7 days per week, for 3 months). The outcome included exercise capacity, lung function test, skeletal muscle strength, dyspnea, and quality of life were measured before and after intervention. RESULTS: A total of 37 participants completed the trial. Compared to the control group, after 3 months of PQE, the mean change in exercise capacity, skeletal muscle strength, and quality of life were statistically significant (P < 0.05, for each), but no significant differences were observed in lung function (except for the forced expiratory volume in one second) and dyspnea (P > 0.05, for each). CONCLUSION: The findings of study suggest that the proposed program of 3 months of PQE intervention has significant improvement in exercise capacity, skeletal muscle strength, and quality of life of COPD-stable patients. TRIAL REGISTRATION: This study was registered in the Chinese Clinical Trial Registry (Trial ID: ChiCTR-1800017405 on 28 July 2018; available at https://www.chictr.org.cn/showproj.html?proj=28343 ).


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qigong , Humanos , Qualidade de Vida , Pulmão , Doença Pulmonar Obstrutiva Crônica/terapia , Exercício Físico , Dispneia/reabilitação
11.
Nanoscale ; 15(48): 19407-19422, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37965689

RESUMO

Treating cancer remains one of the most formidable challenges in modern medicine, with traditional treatment options often being limited by poor therapeutic outcomes and unacceptable side effects. Nanocatalytic therapy activates tumor-localized catalytic reactions in situ via nontoxic or minimally toxic nanocatalysts responding to unique cues from the tumor microenvironment or external stimuli. In particular, sonocatalytic cancer therapy is a promising approach that has emerged as a potential solution to this problem through the combination of ultrasound waves and catalytic materials to selectively target and destroy cancer cells. Compared to light, ultrasound exhibits higher spatial precision, lower energy attenuation, and superior tissue penetrability, furnishing more energy to catalysts. Multidimensional modulation of nanocatalyst structures and properties is pivotal to maximizing catalytic efficiency given constraints in external stimulative energy as well as substrate types and levels. In this review, we discuss the various theories and mechanisms underlying sonocatalytic cancer therapy, as well as advanced catalysts that have been developed for this application. Additionally, we explore the design of sonocatalytic cancer therapy systems, including the use of heterojunction catalysts and the optimal conditions for achieving maximum therapeutic effects. Finally, we highlight the potential benefits of sonocatalytic cancer therapy over traditional cancer treatments, including its noninvasive nature and lower toxicity.


Assuntos
Neoplasias , Humanos , Neoplasias/terapia , Ondas Ultrassônicas , Microambiente Tumoral
12.
Cureus ; 15(9): e45793, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37872914

RESUMO

Hypokalemia may be present in some patients with Sjogren's syndrome. When a patient with Sjogren's syndrome presents with hypokalemia, we would first consider it to be a result of the renal involvement of Sjogren's syndrome. However, in this case report, we present a young woman with Sjogren's syndrome who presented with hypokalemia that was not caused by renal tubular acidosis but by the presence of a coexisting aldosterone-producing adenoma. Cases of Sjogren's syndrome coexisting with aldosterone-producing adenoma are extremely rare. This finding underscores the need for more careful differential diagnosis in patients with Sjogren's syndrome who also have hypokalemia.

13.
Contemp Clin Trials Commun ; 36: 101214, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37842323

RESUMO

Introduction: Negative symptoms and cognitive impairment are common residual symptoms of schizophrenia that seriously affect the quality of life and social function of patients. The intervention of residual symptoms is an important part of schizophrenia rehabilitation. Traditional Chinese exercise has been applied as a supplementary rehabilitation method for schizophrenia. However, research on its use and pertinence in the rehabilitation of residual symptoms remains lacking. In this study, we will verify the intervention effect of a new method, namely, shen-based qigong exercise, on the residual symptoms of schizophrenia, in the hopes of finding a safe and effective rehabilitation method for the residual symptoms of schizophrenia. Methods: This is a single-centre randomised controlled trial. A total of 60 schizophrenics who meet the criteria will be randomly divided into the control and intervention groups in accordance with the ratio of 1:1. Conventional drug treatment will remain unchanged in both groups. In this case, the control group will be given daily rehabilitation, whereas the intervention group will be given daily rehabilitation and shen-based qigong exercise intervention. The intervention period will be 12 weeks. The primary outcome will be negative symptoms assessed by the Scale for the Assessment of Negative Symptoms. The secondary outcome will be the global cognitive function assessed by the Repeatable Battery for the Assessment of Neuropsychological Status and event-related potential P300. Other outcomes will include specific cognitive domain (i.e. working memory), quality of life and social function. The results will be measured within 1 week before and after the intervention. Discussion: The results of this study will likely help find an economical and convenient rehabilitation method for the residual symptoms of schizophrenia and, at the same time, may promote the popularisation and application of traditional Chinese exercises and traditional Chinese medicine theories in the treatment of mental diseases. Trial registration: ClinicalTrials.gov registry number: NCT05310955.

14.
Acta Biomater ; 168: 440-457, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37479159

RESUMO

Cosmetics for perming hair are commonly used but have negative impacts on hair fibers. Repairing damaged hair with conditioners, hair oil, and hair masks can provide relief but cannot prevent injuries. Recent research has shown that proteins and amino acids can remodel hair's disulfide bonds. However, the permeation ability of proteins is limited, and amino acids may disrupt the secondary structure of hair keratins. Our study demonstrates that peptides can be safely, efficiently, and promisingly used for hair perming. A bioinspired peptide, PepACS (PepA-PepC-SPB), was designed through bioinformatics. It can interact with keratin's sulfhydryl group in situ to remodel disulfide bonds without affecting hair fiber's tensile properties. The potential of PepACS to repair cuticle injuries is also observed through scanning electron microscope visualization. Besides, linking PepACS with mCherry enables hair dyeing. This research suggests that biomaterials can be applied in the hair care industry. STATEMENT OF SIGNIFICANCE: Chemical perming products can have negative impacts on people's health and hair fibers, making it essential to explore alternative methods. Peptides treatment is a promising option, but synthesizing sulfur-rich short peptides for hair perming has not been demonstrated before. In this paper, we utilized bioinformatics to design bio-inspired peptides that can interact with hair keratins and form curled shapes. Our study demonstrates that bioinformatics tools can be utilized to design bioinspired peptides with unique functions. Sulfur-rich short peptides can be heterologously expressed with fusion strategies, and PepACS can securely bind hair fibers through disulfide bonds. Importantly, perming hair with 0.01% PepACS maintains the mechanical properties of hair, and dyeing hair with the fusion protein PepACS_mCh can be facilitated by ethanol. These findings suggest that the strategy of perming and dyeing hair through peptides is non-injurious, and the peptides used for repairing hair damage show tremendous potential.


Assuntos
Tinturas para Cabelo , Queratinas Específicas do Cabelo , Humanos , Queratinas Específicas do Cabelo/análise , Queratinas Específicas do Cabelo/metabolismo , Tinturas para Cabelo/análise , Tinturas para Cabelo/química , Tinturas para Cabelo/metabolismo , Proteínas/metabolismo , Peptídeos/metabolismo , Aminoácidos/análise , Cabelo/química , Dissulfetos/metabolismo
15.
Opt Express ; 31(3): 4122-4128, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785387

RESUMO

Sidewall tilting is an important parameter to describe the grating morphology and would affect the diffraction efficiency of three-dimensional (3D) display devices based on pixelated nanogratings. However, there is currently a lack of a non-destructive measurement method that can accurately measure the sidewall tilting of the pixelated nanogratings. This is mainly because the kind of nanograting is manufactured in a micron-scale pixel region and the grating lines generally have various directions to ensure that the display device can display images smoothly. In this work, we propose to use a home-made imaging Mueller matrix ellipsometer (IMME) to monitor sidewall tilting of pixelated nanogratings. Simulation and experiments were carried out to characterize the sidewall tilting angle. Through the combination of Mueller matrix elements, we can quickly and qualitatively identify the tilting angle for the purpose of on-line quality monitoring of the device. Through the inverse calculation of the Mueller matrix, we can accurately and quantitatively obtain the value of the tilting, so as to meet the demands of the device design. It is expected the proposed method can provide guidance for the identification and detection of tilting in 3D display elements based on pixelated gratings.

16.
Artigo em Inglês | MEDLINE | ID: mdl-35954897

RESUMO

With the acceleration of urban construction, the pollutant emission of non-road mobile machinery such as construction machinery is becoming more and more prominent. In this paper, a portable emissions measurement system (PEMS) tested the emissions of eight different types of construction machinery under actual operating conditions and was used for idling, walking, and working under the different emission reduction techniques. The results showed that the pollutant emission of construction machinery is affected by the pollutant contribution of working conditions. According to different emission reduction techniques, the diesel oxidation catalyst (DOC) can reduce carbon monoxide (CO) by 41.6-94.8% and hydrocarbon (HC) by 92.7-95.1%, catalytic diesel particulate filter (CDPF) can reduce particulate matter (PM) by 87.1-99.5%, and selective catalytic reduction (SCR) using urea as a reducing agent can reduce nitrogen oxides (NOx) by 60.3% to 80.5%. Copper-based SCR is better than vanadium-based SCR in NOx reduction. In addition, the study found that when the enhanced 3DOC + CDPF emission reduction technique is used on forklifts, DOC has a "low-temperature saturation effect", which will reduce the emission reduction effect of CO and THC. The use of Burner + DOC + CDPF emission reduction techniques and fuel injection heating process will increase CO's emission factors by 3.2-3.5 and 4.4-6.7 times compared with the actual operating conditions.


Assuntos
Poluentes Atmosféricos , Sidnonas , Poluentes Atmosféricos/análise , Material Particulado/análise , Emissões de Veículos/análise , Emissões de Veículos/prevenção & controle
17.
Opt Lett ; 47(14): 3580-3583, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35838735

RESUMO

The diffraction grating, as an element that can control the direction of the emitted light, is the key component used in holographic sampling three-dimensional (3D) displays. The structural accuracy of nanogratings greatly affects the precision of light modulation, thus influencing the cross talk and resolution in 3D displays. It is of great significance for the nondestructive measurement of nanogratings. However, existing measurement methods have certain limitations such as destructiveness and low measurement efficiency in the face of measuring such pixelated nanogratings. In this work, aimed at the measurement requirements and challenges of pixelated nanogratings in 3D displays, we propose to use a self-designed imaging Mueller matrix ellipsometer (IMME) for grating characterization. A sample containing 6 periods and 10 orientations of pixelated gratings is investigated to verify the effectiveness of the method used. Through the measurement and fitting data, the measurement data obtained by using the IMME can be well matched with the theoretical results. At the same time, the extraction results of the structural parameters, periods, and orientations are also consistent with the measurement results from scanning electron microscopy. It is expected that the IMME will provide a guarantee for the accurate display of 3D holography.

18.
Foods ; 11(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35741918

RESUMO

Deoxynivalenol (DON) contamination in germs and germ oil is posing a serious threat to food and feed security. However, the transformation pathway, the distribution of DON, and its degradation products in edible oil refining have not yet been reported in detail. In this work, we systematically explored the variation of DON in maize germ oil during refining and demonstrated that the DON in germ oil can be effectively removed by refining, during which a part of DON was transferred to the wastes, and another section of DON was degraded during degumming and alkali refining. Moreover, the DON degradation product was identified to be norDON B by using the ultraviolet absorption spectrum, high-performance liquid chromatography (HPLC), ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS), and nuclear magnetic resonance (NMR) methods, and the degradation product was found to be distributed in waste products during oil refining. This study provides a scientific basis and useful reference for the production of non-mycotoxins edible oil by traditional refining.

19.
Adv Healthc Mater ; 11(14): e2200641, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35521819

RESUMO

Clinically, bacteria-induced contagion and insufficient osseointegrative property inevitably elicit the failure of orthopedic implants. Herein, a heterostructured coating consisting of simvastatin (SIM)-laden metal-organic frameworks and polydopamine nanolayers is created on a porous bioinert polyetheretherketone implant. The heterostructured coating significantly promotes cytocompatibility and osteogenic differentiation through multimodal osteogenicity mechanisms of zinc ion (Zn2+ ) therapy, SIM drug therapy, and surface micro-/nano-topological stimulation. Under the illumination of near-infrared (NIR) light, singlet oxygen (1 O2 ) and local hyperthermia are produced; besides, NIR light dramatically accelerates the release of Zn2+ ions from heterostructured coatings. Gram-positive and -negative bacteria are effectively eradicated by the synergy of photothermal/photodynamic effects and photo-induced accelerated delivery of Zn2+ ions. The superior osteogenicity and osseointegration, as well as photoswitchable disinfection controlled by NIR light are corroborated via in vivo results. This work highlights the great potential of photoresponsive heterostructured orthopedic implants in treatment of the noninvasive bone reconstruction of bacteria-associated infectious tissues through multimodal phototherapy and photoswitchable ion-therapy.


Assuntos
Estruturas Metalorgânicas , Osteogênese , Antibacterianos/farmacologia , Benzofenonas , Desinfecção , Indóis , Íons/farmacologia , Estruturas Metalorgânicas/farmacologia , Polietilenoglicóis/farmacologia , Polímeros , Staphylococcus aureus
20.
RSC Adv ; 12(18): 11090-11099, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35425054

RESUMO

Drug-free antibacterial strategies are of great significance for pathogenic bacterial infection treatment in clinical practice. Phototherapy with antibacterial function plays a vital role in mainstream germicidal research. However, phototherapy could lead to residual heat and excess reactive oxygen species (ROS), which are the main side-effects during antibacterial treatment. Unique CoFe2O4/MXene (CM) nanoenzymes, which were fabricated with electrostatic interactions, have been designed to conquer those challenges caused by side-effects of phototherapy in our research. The CM nanoenzymes possess many promising properties including photothermal and photodynamic induced phototherapy and mimic peroxidase (POD), glutathione oxidase (GSHOx), and catalase (CAT). Upon treatment with near-infrared (NIR) light, CM nanoenzymes can create a local high-temperature circumstance as well as raise bacterial membrane permeability. Furthermore, the photodynamic process and multi-enzyme-mimicking activities of CM enzymes boost the interbacterial ROS level. Herein, bacteria can hardly survive in synergistic phototherapy and multi-enzyme-mimicking catalytic therapy in vitro and in vivo. Meanwhile, the CM nanoenzymes exhibit excellent biocompatibility in vitro and in vivo. Overall, this research establishes a strong foundation for effectively employing nanoenzymes, leading to a new way to cure bacterial infections.

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