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1.
Phys Rev Lett ; 132(24): 243802, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949371

RESUMO

Orbital angular momentum (OAM) provides an additional degree of freedom for optical communication systems, and manipulating on-chip OAM is important in integrated photonics. However, there is no effective method to realize OAM topological charge conversion on chip. In this Letter, we propose a way to convert OAM by encircling two groups of exceptional points in different Riemann sheets. In our framework, any OAM conversion can be achieved on demand just by manipulating adiabatic and nonadiabatic evolution of modes in two on-chip waveguides. More importantly, the chiral OAM conversion is realized, which is of great significance since the path direction can determine the final topological charge order. Our Letter presents a special chiral behavior and provides a new method to manipulate OAM on the chip.

2.
Neural Plast ; 2024: 5599046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529366

RESUMO

Low back pain (LBP) is a leading cause of global disabilities. Numerous molecular, cellular, and anatomical factors are implicated in LBP. Current issues regarding neurologic alterations in LBP have focused on the reorganization of peripheral nerve and spinal cord, but neural mechanisms of exactly what LBP impacts on the brain required further researches. Based on existing clinical studies that chronic pain problems were accompanying alterations in brain structures and functions, researchers proposed logical conjectures that similar alterations occur in LBP patients as well. With recent extensive studies carried out using noninvasive neuroimaging technique, increasing number of abnormalities and alterations has been identified. Here, we reviewed brain alterations including white matters, grey matters, and neural circuits between brain areas, which are involved in chronic LBP. Moreover, brain structural and functional connectivity abnormalities are correlated to the happening and transition of LBP. The negative emotions related to back pain indicate possible alterations in emotional brain regions. Thus, the aim of this review is to summarize current findings on the alterations corresponding to LBP in the brain. It will not only further our understanding of etiology of LBP and understanding of negative emotions accompanying with back pain but also provide ideas and basis for new accesses to the diagnosis, treatment, and rehabilitation afterward based on integral medicine.


Assuntos
Dor Lombar , Humanos , Encéfalo/diagnóstico por imagem , Emoções , Medula Espinal
3.
Sensors (Basel) ; 24(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39001006

RESUMO

Infrared small target detection technology plays a crucial role in various fields such as military reconnaissance, power patrol, medical diagnosis, and security. The advancement of deep learning has led to the success of convolutional neural networks in target segmentation. However, due to challenges like small target scales, weak signals, and strong background interference in infrared images, convolutional neural networks often face issues like leakage and misdetection in small target segmentation tasks. To address this, an enhanced U-Net method called MST-UNet is proposed, the method combines multi-scale feature decomposition and fusion and attention mechanisms. The method involves using Haar wavelet transform instead of maximum pooling for downsampling in the encoder to minimize feature loss and enhance feature utilization. Additionally, a multi-scale residual unit is introduced to extract contextual information at different scales, improving sensory field and feature expression. The inclusion of a triple attention mechanism in the encoder structure further enhances multidimensional information utilization and feature recovery by the decoder. Experimental analysis on the NUDT-SIRST dataset demonstrates that the proposed method significantly improves target contour accuracy and segmentation precision, achieving IoU and nIoU values of 80.09% and 80.19%, respectively.

4.
J Environ Manage ; 351: 119978, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38169258

RESUMO

Global climate change exerts a significant impact on sustainable horticultural crop production and quality. Rising Global temperatures have compelled the agricultural community to adjust planting and harvesting schedules, often necessitating earlier crop cultivation. Notably, climate change introduces a suite of ominous factors, such as greenhouse gas emissions (CGHs), including elevated temperature, increased carbon dioxide (CO2) concentrations, nitrous oxide (N2O) and methane (CH4) ozone depletion (O3), and deforestation, all of which intensify environmental stresses on crops. Consequently, climate change stands poised to adversely affect crop yields and livestock production. Therefore, the primary objective of the review article is to furnish a comprehensive overview of the multifaceted factors influencing horticulture production, encompassing fruits, vegetables, and plantation crops with a particular emphasis on greenhouse gas emissions and environmental stressors such as high temperature, drought, salinity, and emission of CO2. Additionally, this review will explore the implementation of novel horticultural crop varieties and greenhouse technology that can contribute to mitigating the adverse impact of climate change on agricultural crops.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Mudança Climática , Dióxido de Carbono/análise , Agricultura , Produtos Agrícolas , Horticultura , Óxido Nitroso/análise , Metano/análise , Solo
5.
Molecules ; 29(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39125046

RESUMO

Supercapacitors (SCs) are widely recognized as competitive power sources for energy storage. The hierarchical structure of nickel vanadium sulfide nanoparticles encapsulated on graphene nanosheets (NVS/G) was fabricated using a cost-effective and scalable solvothermal process. The reaction contents of the composites were explored and optimized. TEM images displayed the nickel vanadium sulfide nanoparticles (NVS NPs) with 20-30 nm average size anchored to graphene nanosheets. The interconnection of graphene nanosheets encapsulating NVS nanoparticles effectively reduces the ion diffusion path between the electrode and electrolyte, thereby enhancing electrochemical performance. The NVS/G composite demonstrated improved electrochemical performance, achieving a maximum of 1437 F g-1 specific capacitance at 1 A g-1, remarkable rate capability retaining of 1050 F g-1 at 20 A g-1, and exceptional cycle stability with 91.2% capacitance retention following 10,000 cycles. The NVS/G composite was employed as a cathode, and reduced graphene oxide (rGO) was used as an anode material to assemble a device. Importantly, asymmetric SCs using NVS/G//rGO achieved 74.7 W h kg-1 energy density at 0.8 kW kg-1 power density, along with outstanding stability with 88.2% capacitance retention following 10,000 cycles. These superior properties of the NVS/G electrode highlight its significant potential in energy storage applications.

6.
Angew Chem Int Ed Engl ; 63(12): e202318784, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38291557

RESUMO

Plitidepsin (or dehydrodidemnin B), an approved anticancer drug, belongs to the didemnin family of cyclic depsipeptides, which are found in limited quantities in marine tunicate extracts. Herein, we introduce a new approach that integrates microbial and chemical synthesis to generate plitidepsin and its analogues. We screened a Tistrella strain library to identify a potent didemnin B producer, and then introduced a second copy of the didemnin biosynthetic gene cluster into its genome, resulting in a didemnin B titer of approximately 75 mg/L. Next, we developed two straightforward chemical strategies to convert didemnin B into plitidepsin, one of which involved a one-step synthetic route giving over 90 % overall yield. Furthermore, we synthesized 13 new didemnin derivatives and three didemnin probes, enabling research into structure-activity relationships and interactions between didemnin and proteins. Our study highlights the synergistic potential of biosynthesis and chemical synthesis in overcoming the challenge of producing complex natural products sustainably and at scale.


Assuntos
Antineoplásicos , Depsipeptídeos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/metabolismo , Depsipeptídeos/farmacologia , Antineoplásicos/farmacologia , Relação Estrutura-Atividade
7.
Small ; : e2310612, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087883

RESUMO

The biological system realizes the unity of action and perception through the muscle tissue and nervous system. Correspondingly, artificial soft actuators realize the unity of sensing and actuating functions in a single functional material, which will have tremendous potential for developing intelligent and bionic soft robotics. This paper reports the design of a laser-induced graphene (LIG) electrothermal actuator with self-sensing capability. LIG, a functional material formed by a one-step direct-write lasing procedure under ambient air, is used as electrothermal conversion materials and piezoresistive sensing materials. By transferring LIG to a flexible silicone substrate, the design ability of the LIG-based actuator unit is enriched, along with an effectively improved sensing sensitivity. Through the integration of different types of well-designed LIG-based actuator units, the transformations from multidimensional precursors to 2D and 3D structures are realized. According to the piezoresistive effect of the LIG units during the deformation process, the visual synchronous deformation state feedback of the LIG-based actuator is proposed. The multimodal crawling soft robotics and the switchable electromagnetic shielding cloak serve as the demonstrations of the self-sensing LIG-based actuator, showing the advantage of the design in remote control of the soft robot without relying on the assistance of visual devices.

8.
Appl Opt ; 62(17): 4543-4550, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707150

RESUMO

It is important to determine the ideal combination of housing materials, groups of refractive materials, and their optical powers for athermalizing achromatic and apochromatic optical systems. This study proposes a combined design approach that utilizes three or more glass types to resolve thermal aberrations and defocus achromatic and apochromatic optical systems. It selects a suitable glass type using a 3D glass chart and calculates the optical power analytically. Furthermore, a temperature-insensitive optical system with a 450-750 nm band based on refractive materials (CDGM Glass Co., Ltd.) is designed, with the modular transfer function value of the center field of view decreasing by less than 0.024 in the temperature range of -40∘ C to +80∘ C and the secondary spectrum aberration decreasing by over three times and being maintained within 0.08 mm.

9.
Pestic Biochem Physiol ; 197: 105651, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072526

RESUMO

Solenopsis invicta is a main issue in southern China and is causing significant damage to the local ecological environment. The extensive use of insecticides has resulted in the development of tolerance in S. invicta. In our study, ten S. invicta colonies from Sichuan Province exhibited varying degrees of tolerance against flonicamid, with LC50 values from 0.49 mg/L to 8.54 mg/L. The sensitivity of S. invicta to flonicamid significantly increased after treatment with the P450 enzyme inhibitor piperonyl butoxide (PBO). Additionally, the activity of P450 in S. invicta was significantly enhanced after being treated with flonicamid. Flonicamid induced the expression levels of CYP4aa1, CYP9e2, CYP4C1, and CYP6A14. The expression levels of these P450 genes were significantly higher in the tolerant colonies compared to the sensitive colonies, and the relative copy numbers of CYP6A14 in the tolerant colonies were 2.01-2.15 fold. RNAi feeding treatment effectively inhibited the expression of P450 genes, thereby reducing the tolerance of S. invicta against flonicamid. In addition, the overexpression of CYP6A14 in D. melanogaster resulted in reduced sensitivity to flonicamid. Our investigations revealed hydrophobic interactions between flonicamid and seven amino acid residues of CYP6A14, along with the formation of a hydrogen bond between Glu306 and flonicamid. Our findings suggest that flonicamid can effectively control S. invicta and P450 plays a pivotal role in the tolerance of S. invicta against flonicamid. The overexpression of CYP6A14 also increased tolerance to flonicamid.


Assuntos
Formigas , Inseticidas , Animais , Formigas Lava-Pés , Drosophila melanogaster , Inseticidas/toxicidade
10.
Sensors (Basel) ; 23(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37050754

RESUMO

This paper proposes a new pose and focal length estimation method using two vanishing points and a known camera position. A vanishing point can determine the unit direction vector of the corresponding parallel lines in the camera frame, and as input, the unit direction vector of the corresponding parallel lines in the world frame is also known. Hence, the two units of direction vectors in camera and world frames, respectively, can be transformed into each other only through the rotation matrix that contains all the information of the camera pose. Then, two transformations can be obtained because there are two vanishing points. The two transformations of the unit direction vectors can be regarded as transformations of 3D points whose coordinates are the values of the corresponding unit direction vectors. The key point in this paper is that our problem with vanishing points is converted to rigid body transformation with 3D-3D point correspondences, which is the usual form in the PnP (perspective-n-point) problem. Additionally, this point simplifies our problem of pose estimation. In addition, in the camera frame, the camera position and two vanishing points can form two lines, respectively, and the angle between the two lines is equal to the angle between the corresponding two sets of parallel lines in the world frame. When using this geometric constraint, the focal length can be estimated quickly. The solutions of pose and focal length are both unique. The experiments show that our proposed method has good performances in numerical stability, noise sensitivity and computational speed with synthetic data and real scenarios and also has strong robustness to camera position noise.

11.
J Sci Food Agric ; 103(10): 4850-4857, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36917022

RESUMO

BACKGROUND: Rice starch retrogradation is prone to occur during instant rice storage, which contributes to reduced viscosity, poor sensory characteristics, and shortened shelf life. The purpose of this study was to explore the anti-retrogradation effect of soybean soluble polysaccharides (SSPS) on instant rice and the possible interaction between SSPS and high-moisture starch products. RESULTS: We studied the effects of SSPS on the retrogradation of instant rice, using hardness as an index. The optimal amount of SSPS was 0.2%. Hardness, enthalpy, relative crystallinity, and full width at half maximum values were lower in the SSPS-treated group than in the control group (no SSPS) during storage. The weight loss rate of instant rice had the following trend: SSPS-treated group (0 day) < control group (0 day) < SSPS-treated group (28 days) < control group (28 days). The lower the weight loss rate, the lower was the material loss. Scanning electron microscopy results showed that the gaps between starch granules were less obvious in the control group than in the SSPS-treated group during storage. The SSPS-treated group presented a starch network with uniform chambers. SSPS might compete with starch molecules for water absorption, thereby improving water retention and limiting starch retrogradation. CONCLUSION: The results showed that adding SSPS to instant rice could effectively inhibit starch retrogradation, because the interaction of SSPS and amylopectin side chains inhibited the crosslinking of starch molecules through hydrogen bonds, which hindered the formation of ordered structures. It was helpful to understand the anti-retrogradation mechanism of SSPS during the storage of instant rice, and provided the basis for the industrial production of high-water-content starch foods. © 2023 Society of Chemical Industry.


Assuntos
Oryza , Oryza/química , Glycine max , Polissacarídeos , Amido/química , Água
12.
Beilstein J Org Chem ; 19: 998-1007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404799

RESUMO

Five new eudesmane-type sesquiterpenoids (aquisinenoids F-J (1-5)) and five known compounds (6-10) were isolated from the agarwood of Aquilaria sinensis. Their structures, including absolute configurations, were identified by comprehensive spectroscopic analyses and computational methods. Inspired by our previous study on the same kinds of skeletons, we speculated that the new compounds have anticancer and anti-inflammatory activities. The results did not show any activity, but they revealed the structure-activity relationships (SAR).

13.
Sensors (Basel) ; 22(14)2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35890821

RESUMO

In industrial production, flaws and defects inevitably appear on surfaces, resulting in unqualified products. Therefore, surface defect detection plays a key role in ensuring industrial product quality and maintaining industrial production lines. However, surface defects on different products have different manifestations, so it is difficult to regard all defective products as being within one category that has common characteristics. Defective products are also often rare in industrial production, making it difficult to collect enough samples. Therefore, it is appropriate to view the surface defect detection problem as a semi-supervised anomaly detection problem. In this paper, we propose an anomaly detection method that is based on dual attention and consistency loss to accomplish the task of surface defect detection. At the reconstruction stage, we employed both channel attention and pixel attention so that the network could learn more robust normal image reconstruction, which could in turn help to separate images of defects from defect-free images. Moreover, we proposed a consistency loss function that could exploit the differences between the multiple modalities of the images to improve the performance of the anomaly detection. Our experimental results showed that the proposed method could achieve a superior performance compared to the existing anomaly detection-based methods using the Magnetic Tile and MVTec AD datasets.


Assuntos
Algoritmos
14.
Molecules ; 27(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35684345

RESUMO

Transition metal-substituted polyoxometalates (POMs) were filled into a metal-organic framework (MOF) to construct a series of POM@MOF composites (PMo12O40@MIL-101, PMo11VO40@MIL-101, PMo10V2O40@MIL-101). The composite materials possess ultra-high adsorption ability, especially for PMo10V2O40@MIL-101, with an adsorption capacity of 912.5 mg·g-1 for cationic antibiotic tetracycline in wastewater, much higher than that of isolated MIL-101(Fe) and the commonly used adsorption materials, such as activated carbon and graphene oxide. In particular, they can be used as efficient photocatalysts for the photodegradation of antibiotics under visible light irradiation. The complete photodegradation of the adsorbed species can induce the facile reusability of these composites for multiple cycles. This work opens an avenue to introduce POMs into an MOF matrix for the simultaneous adsorption and photodegradation of antibiotics.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Poluentes Químicos da Água , Adsorção , Antibacterianos , Luz
15.
J Gene Med ; 23(8): e3349, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33899983

RESUMO

BACKGROUND: Propofol (PPF) plays a protective role in ischemia-reperfusion (I/R) in multiple organs, including renal ischemia-reperfusion injury (RIRI). The present study aimed to investigate the underlying mechanisms by which PPF exerts its protective functions in RIRI. METHODS: BALB/c mice were employed for the construction of RIRI animal model. PPF pre-treatment was carried out before I/R. An in vitro I/R model was established with HK-2 cells after hypoxia/reoxygenation (H/R) culture, and PPF was utilized to treat the cells before H/R. A quantitative-polymerase chain reaction (qPCR) was conducted to detect long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and miR-126-5p expression levels. Flow cytometry was adopted to detect the apoptosis of HK-2 cells. Bioinformatics analysis, qPCR, a luciferase reporter gene experiment and a RNA immunoprecipitation experiment were used to determine the regulatory relationship between MALAT1 and miR-126-5p. The expression level of vascular endothelial growth factor A (VEGFA) was examined by western blotting. RESULTS: MALAT1 expression was augmented and miR-126-5p was decreased in RIRI models. PPF pre-treatment remarkably reduced creatinine and urea nitrogen levels in the serum of BALB/c mice with RIRI, and diminished the apoptosis of HK-2 cells treated with H/R. In addition, PPF pre-treatment markedly restrained the expression of MALAT1 in both in vivo and in vitro models and up-regulated miR-126-5p expression. MALAT1 could adsorb miR-126-5p to repress it and up-regulate VEGFA. MALAT1 overexpression reversed the protective effects of PPF on RIRI. CONCLUSIONS: PPF protects the kidney against RIRI by inhibiting MALAT1 and up-regulating miR-126-5p expression, as well as indirectly inhibiting the expression of VEGFA.


Assuntos
MicroRNAs/genética , Propofol/farmacologia , RNA Longo não Codificante/genética , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Túbulos Renais/citologia , Masculino , Camundongos Endogâmicos BALB C , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Fator A de Crescimento do Endotélio Vascular/genética
16.
Exp Cell Res ; 390(1): 111937, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32135165

RESUMO

The proliferation and migration of Schwann cells contribute to nerve regeneration after peripheral nerve injury (PNI). In recent years, roles of long non-coding RNAs (lncRNAs) in PNI have been gradually uncovered. However, a highly conserved nuclear lncRNA Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in peripheral nerve regeneration remains enigmatic. MALAT1 expression in injured sciatic nerve of mice with PNI was measured by real-time PCR. The proliferative and migrative abilities of Schwann cells were determined after upregulating or downregulating Malat1. The relationship among MALAT1, miR-129-5p, and BDNF was measured. In this study, we found elevated MALAT1 expression in injured sciatic nerve. MALAT1 upregulation in Schwann cells promoted cell proliferation and migration. However, downregulation of MALAT1 caused the suppression of Schwann cell proliferation and migration. Mechanistically, we discovered MALAT1 negatively regulated miR-129-5p through directly binding. Brain-derived neurotrophic factor (BDNF) was a target of miR-129-5p. MALAT1 positively modulated BDNF expression and secretion via decreasing miR-129-5p. Downregulation of BDNF rescued the influences of MALAT1 overexpression on Schwann cell proliferation and migration. In conclusion, MALAT1 was enhanced after PNI and it promoted the proliferation and migration of Schwann cells through sponging miR-129-5p to increase BDNF expression and secretion. This study proved that MALAT1 may be a vital regulator in peripheral nerve regeneration.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Movimento Celular , Proliferação de Células , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Células de Schwann/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , RNA Longo não Codificante/genética , Células de Schwann/fisiologia
17.
Exp Cell Res ; 388(1): 111803, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31877301

RESUMO

Schwann cells, a crucial element in peripheral nervous system, play important roles after peripheral nerve injury. In recent years, the role of miR-485-5p has been discovered in neurological diseases. However, the involvement of miR-485-5p and peripheral nerve injury remains unknown. Mice were subjected to sciatic nerve crush to mimic peripheral nerve injury and the expression of miR-485-5p was detected in sciatic nerve stumps by real-time PCR. BrdU assay was used to analyze the proliferation of Schwann cells after transfection with miR-485-5p mimic and miR-485-5p inhibitor. The effect of miR-485-5p on Schwann cell myelination was determined by evaluating levels of cyclic adenosine monophosphate (cAMP)-induced myelin-associated proteins, including Krox20 and MBP, as well as the coculture of Schwann cells and dorsal root ganglion (DRG) neurons via immunostaining with anti-MBP antibodies. The regulation mechanism of miR-485-5p was measured by bioinformatics analysis, luciferase reporter assay, and real-time PCR and Western blot. We found miR-485-5p expression was downregulated post nerve injury. miR-485-5p mimic significantly suppressed the proliferation and cAMP-induced expression levels of Krox20 and MBP in Schwann cells. Conversely, miR-485-5p inhibitor promoted these changes in Schwann cells. Also, miR-485-5p inhibitor elevated MBP-positive myelinated fibers. Cdc42 and Rac1 are targets of miR-485-5p in Schwann cells. Downregulation of cdc42 reversed the effect of miR-485-5p inhibitor on the proliferation of Schwann cells. And reducing Rac1 expression attenuated the effect of miR-485-5p silencing on Schwann cell myelination. In conclusion, this study indicated that miR-485-5p suppressed the proliferation and myelination of Schwann cells via targeting cdc42 and Rac1. Which may provide a novel method for the treatment of peripheral nerve injury.


Assuntos
Proliferação de Células , MicroRNAs/metabolismo , Bainha de Mielina/metabolismo , Neuropeptídeos/genética , Traumatismos dos Nervos Periféricos/metabolismo , Células de Schwann/metabolismo , Proteína cdc42 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/genética , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neuropeptídeos/metabolismo , Traumatismos dos Nervos Periféricos/genética , Células de Schwann/fisiologia , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
18.
Int Arch Allergy Immunol ; 181(6): 446-455, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32299080

RESUMO

BACKGROUND: Wheat is known as the most widely consumed food all over the world. Although many types of wheat allergy have been recognized, their treatment still has a long way to go due to the complex pathogenesis. Oral immunotherapy (OIT) is under investigation for the treatment of wheat allergies. Previous studies have demonstrated that OIT using intact wheat allergens can induce tolerance, but is accompanied by a high risk of anaphylactic reactions. OBJECTIVES: Our objective was to prepare modified wheat allergens with hypoallergenic and tolerance-inducing properties to reduce adverse effects during immunotherapy. METHODS: Wheat gliadin was degraded by hydrolysis with pepsin and trypsin, and then the hydrolysate was deamidated with hydrochloric acid. The IgE-binding capacity and T cell reactivity of the degraded gliadins were evaluated in vitro. Pepsin-digested gliadin (peptic-GLI) was applied in a mouse model to investigate whether it would induce oral tolerance. RESULTS: Degradation with pepsin decreased IgE-binding capacity and maintained T cell reactivity. Oral administration of peptic-GLI to mice before sensitization and challenge with gliadin could significantly suppress the production of IgE, IgG1, and type 2 T helper cytokines. Moreover, the development of anaphylactic reactions and allergic responses of the small intestine induced by gliadin challenge were inhibited by oral administration of peptic-GLI. CONCLUSIONS: The findings of this study indicate that peptic-GLI with low allergenicity and potential for tolerance induction may become useful in wheat immunotherapy with less adverse effects.


Assuntos
Alérgenos/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Dessensibilização Imunológica/métodos , Gliadina/uso terapêutico , Tolerância Imunológica , Hipersensibilidade a Trigo/terapia , Administração Oral , Alérgenos/imunologia , Alérgenos/metabolismo , Animais , Feminino , Gliadina/imunologia , Gliadina/metabolismo , Hidrólise , Camundongos , Camundongos Endogâmicos BALB C , Pepsina A/metabolismo , Hipersensibilidade a Trigo/imunologia
19.
Protein Expr Purif ; 175: 105714, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32738434

RESUMO

Cancer immunotherapy has recently attracted attention as an approach for cancer treatment through the activation of the immune system. Group-specific component (Gc) protein is a precursor for macrophage activating factor (GcMAF), which has a promising immunomodulatory effect on the suppression of tumor growth and angiogenesis. In this study, we successfully purified Gc protein from human serum using anion-exchange chromatography combined with affinity chromatography using a 25-OH-D3-immobilized column. The purity of Gc protein reached 95.0% after anion-exchange chromatography. The known allelic variants of Gc protein are classified into three subtypes-Gc1F, Gc1S and Gc2. The fragment sequence of residues 412-424 determined according to their MS/MS spectra is available to evaluate the subtypes of Gc protein. The data showed that the Gc protein purified in this study consisted of the Gc1F and Gc2 subtypes. Our method improved the purity of Gc protein, which was not affected by the treatment to convert it into GcMAF using ß-galactosidase- or neuraminidase-immobilized resin, and will be useful for biological studies and/or advanced clinical uses of GcMAF, such as cancer immunotherapy.


Assuntos
Cromatografia de Afinidade , Fatores Ativadores de Macrófagos , Proteína de Ligação a Vitamina D , Humanos , Fatores Ativadores de Macrófagos/química , Fatores Ativadores de Macrófagos/isolamento & purificação , Proteína de Ligação a Vitamina D/química , Proteína de Ligação a Vitamina D/isolamento & purificação
20.
Biotechnol Appl Biochem ; 67(5): 783-789, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31584216

RESUMO

Microalgae are potential candidate for biofuel production as alternative one for fossil fuels. CO2 in flue gas is available carbon source to support microalgae growth. In this study, the effects of different concentrations of the simulated flue gas onto algal growth and photosynthetic activity were evaluated for both Chlorella sp. AE10 and Chlorella sp. Cv. The growth profiles were correlated by a simple kinetic model. It was indicated that the simulated flue gas led to low pH and the photosynthetic activity was partially destroyed. Chlorella sp. Cv can tolerate full simulated flue gas, 10% CO2  + 200 ppm NOx  + 100 ppm SOx . The pH in medium maintained at 6 and the photosynthetic activity was more than 0.6 at the first 6 days. If the concentration of NOx was more 100 ppm and that of SOx was more than 50 ppm, the pH was declined to 4 at day 2 or 3 for Chlorella sp. AE10. At the same time, the related photosynthetic activities of Chlorella sp. AE10 were less than 0.4, which was not suitable for algal growth. It was shown that Chlorella sp. Cv could be used for CO2 fixation from the simulated flue gas.


Assuntos
Dióxido de Carbono/metabolismo , Chlorella/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Cinética , Modelos Biológicos , Óxidos de Nitrogênio/metabolismo , Fotossíntese
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