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1.
Nature ; 590(7846): 416-422, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33597761

RESUMO

Crystallization by particle attachment (CPA) is a frequently occurring mechanism of colloidal crystallization that results in hierarchical morphologies1-4. CPA has been exploited to create nanomaterials with unusual properties4-6 and is implicated in the development of complex mineral textures1,7. Oriented attachment7,8-a form of CPA in which particles align along specific crystallographic directions-produces mesocrystals that diffract as single crystals do, although the constituent particles are still discernible2,9. The conventional view of CPA is that nucleation provides a supply of particles that aggregate via Brownian motion biased by attractive interparticle potentials1,9-12. However, mesocrystals often exhibit regular morphologies and uniform sizes. Although many crystal systems form mesocrystals1-9 and individual attachment events have been directly visualized10, how random attachment events lead to well defined, self-similar morphologies remains unknown, as does the role of surface-bound ligands, which are ubiquitous in nanoparticle systems3,9,11. Attempts to understand mesocrystal formation are further complicated in many systems by the presence of precursor nanoparticles with a phase distinct from that of the bulk1,13,14. Some studies propose that such particles convert before attachment15, whereas others attribute conversion to the attachment process itself16 and yet others conclude that transformation occurs after the mesocrystals exceed a characteristic size14,17. Here we investigate mesocrystal formation by iron oxides, which are important colloidal phases in natural environments18,19 and classic examples of systems forming ubiquitous precursor phases and undergoing CPA accompanied by phase transformations15,19-21. Combining in situ transmission electron microscopy (TEM) at 80 degrees Celsius with 'freeze-and-look' TEM, we tracked the formation of haematite (Hm) mesocrystals in the presence of oxalate (Ox), which is abundant in soils, where iron oxides are common. We find that isolated Hm particles rarely appear, but once formed, interfacial gradients at the Ox-covered surfaces drive Hm particles to nucleate repeatedly about two nanometres from the surfaces, to which they then attach, thereby generating mesocrystals. Comparison to natural and synthetic systems suggests that interface-driven pathways are widespread.

2.
Environ Sci Technol ; 58(27): 12113-12122, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38917351

RESUMO

Size and purity of metal phosphate and metal sulfide colloids can control the solubility, persistence, and bioavailability of metals in environmental systems. Despite their importance, methods for detecting and characterizing the diversity in the elemental composition of these colloids in complex matrices are missing. Here, we develop a single-particle inductively coupled plasma time-of-flight mass spectrometry (sp-icpTOF-MS) approach to characterize the elemental compositions of individual metal phosphate and sulfide colloids extracted from complex matrices. The stoichiometry was accurately determined for particles of known composition with an equivalent spherical diameter of ≥∼200 nm. Assisted by machine learning (ML), the new method could distinguish particles of the copper sulfides covellite (CuS), chalcocite (Cu2S), and chalcopyrite particles (CuFeS2) with 75% (for Cu2S) to 99% (for CuFeS2) accuracy. Application of the sp-icpTOF-MS method to particles recovered from natural samples revealed that iron sulfide (FeS) particles in lake sediment contained ∼4% copper and zinc impurities, whereas pure pyrite (FeS2) was identified in hydraulic fracturing wastewater and confirmed by selected area electron diffraction. Colloidal mercury in an offshore marine sediment was present as pure mercury sulfide (HgS), whereas geogenic HgS recovered from an industrial process contained ∼0.08 wt % silver per Hg, enabling source apportionment of these colloids using ML. X-ray absorption spectroscopy confirmed that Hg was predominantly present as metacinnabar (ß-HgS) in the industrial process sample. The determination of impurities in individual colloids, such as zinc and copper in FeS, and silver in HgS may enable improved assessment of their origin, reactivity, and bioavailability potential.


Assuntos
Coloides , Espectrometria de Massas , Fosfatos , Solo , Sulfetos , Coloides/química , Sulfetos/química , Solo/química , Fosfatos/química , Sedimentos Geológicos/química , Metais/química
3.
Environ Sci Technol ; 58(6): 2798-2807, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38294779

RESUMO

Solar photoexcitation of chromophoric groups in dissolved organic matter (DOM), when coupled to photoreduction of ubiquitous Fe(III)-oxide nanoparticles, can significantly accelerate DOM degradation in near-surface terrestrial systems, but the mechanisms of these reactions remain elusive. We examined the photolysis of chromophoric soil DOM coated onto hematite nanoplatelets featuring (001) exposed facets using a combination of molecular spectroscopies and density functional theory (DFT) computations. Reactive oxygen species (ROS) probed by electron paramagnetic resonance (EPR) spectroscopy revealed that both singlet oxygen and superoxide are the predominant ROS responsible for DOM degradation. DFT calculations confirmed that Fe(II) on the hematite (001) surface, created by interfacial electron transfer from photoexcited chromophores in DOM, can reduce dioxygen molecules to superoxide radicals (•O2-) through a one-electron transfer process. 1H nuclear magnetic resonance (NMR) and electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) spectroscopies show that the association of DOM with hematite enhances the cleavage of aromatic groups during photodegradation. The findings point to a pivotal role for organic matter at the interface that guides specific ROS generation and the subsequent photodegradation process, as well as the prospect of using ROS signatures as a forensic tool to help interpret more complicated field-relevant systems.


Assuntos
Matéria Orgânica Dissolvida , Compostos Férricos , Espécies Reativas de Oxigênio , Superóxidos , Fotólise
4.
Skin Res Technol ; 30(7): e13787, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38992866

RESUMO

BACKGROUD: Previous observational studies have shown that vitiligo usually co-manifests with a variety of dysglycemic diseases, such as Type 1 diabetes mellitus (T1DM) and Type 2 diabetes mellitus (T2DM). Mendelian randomization (MR) analysis was performed to further evaluate the causal association between fasting plasma glucose, glycosylated hemoglobin (HbA1c), T1DM, T2DM and vitiligo. MATERIALS AND METHODS: We used aggregated genome-wide association data from the Integrative Epidemiology Unit (IEU) online database of European adults vitiligo; HbA1c data were from IEU. Fasting blood glucose data were obtained from the European Bioinformatics Institute (EBI). T1DM and T2DM data were from FinnGen. We used bidirectional two-sample and multivariate MR analyses to test whether dysglycemic measures (fasting blood glucose, HbA1c), diabetes-related measures (T1DM, T2DM) are causatively associated with vitiligo. Inverse variance weighting (IVW) method was used as the main test method, MR-Egger, Weighted mode and Weighted median were used as supplementary methods. RESULTS: We found no statistically significant evidence to support a causal association between dysglycemic traits and vitiligo, but in the correlation analysis of diabetic traits, our data supported a positive causal association between T1DM and vitiligo (p = 0.018). In the follow-up multivariate MR analysis, our results still supported this conclusion (p = 0.016), and suggested that HbA1c was not a mediator of T1DM affecting the pathogenesis of vitiligo. No reverse causality was found in any of the reverse MR Analyses of dysglycemic traits and diabetic traits. CONCLUSIONS: Our findings support that T1DM is a risk factor for the development of vitiligo, and this conclusion may explain why the co-presentation of T1DM and vitiligo is often seen in observational studies. Clinical use of measures related to T1DM may be a new idea for the prevention or treatment of vitiligo.


Assuntos
Glicemia , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Estudo de Associação Genômica Ampla , Hemoglobinas Glicadas , Análise da Randomização Mendeliana , Vitiligo , Vitiligo/genética , Vitiligo/sangue , Vitiligo/epidemiologia , Humanos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Hemoglobinas Glicadas/metabolismo , Fatores de Risco , Adulto , Masculino , Feminino
5.
Pharm Biol ; 62(1): 214-221, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38353262

RESUMO

CONTEXT: Polyporus polysaccharide (PPS), the leading bioactive ingredient extracted from Polyporus umbellatus (Pers.) Fr. (Polyporaceae), has been demonstrated to exert anti-bladder cancer and immunomodulatory functions in macrophages. OBJECTIVE: To explore the effects of homogeneous Polyporus polysaccharide (HPP) on the proliferation and autophagy of bladder cancer cells co-cultured with macrophages. MATERIALS AND METHODS: MB49 bladder cancer cells and RAW264.7 macrophages were co-cultured with or without HPP intervention (50, 100, or 200 µg/mL) for 24 h. The cell counting kit-8 (CCK-8) assay and 5-ethynyl-2″-deoxyuridine (EdU) staining evaluated MB49 cell proliferation. Monodansylcadaverine (MDC) staining and transmission electron microscopy (TEM) observed autophagosomes. Western blotting detected the expression levels of autophagy-related proteins and PI3K/Akt/mTOR pathway proteins. RESULTS: HPP inhibited the proliferation of MB49 cells co-cultured with RAW264.7 cells but not MB49 cells alone. HPP altered the expression of autophagy-related proteins and promoted the formation of autophagosomes in MB49 cells in the co-culture system. Autophagy inhibitors 3-methyladenine (3-MA) and chloroquine (CQ) not only antagonized HPP-induced autophagy but also attenuated the inhibitory effects of HPP on MB49 cell proliferation in the co-culture system. HPP or RAW264.7 alone was not sufficient to induce autophagy in MB49 cells. In addition, HPP suppressed the protein expression of the PI3K/Akt/mTOR pathway in MB49 cells in the co-culture system. DISCUSSION AND CONCLUSIONS: HPP induced bladder cancer cell autophagy by regulating macrophages in the co-culture system, resulting in the inhibition of cancer cell proliferation. The PI3K/Akt/mTOR pathway was involved in HPP-induced autophagy in the co-culture system.


Assuntos
Polyporus , Neoplasias da Bexiga Urinária , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Apoptose , Polyporus/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Proliferação de Células , Polissacarídeos/farmacologia , Proteínas Relacionadas à Autofagia/farmacologia
6.
J Am Chem Soc ; 145(5): 2930-2940, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36696237

RESUMO

Surface terminations and defects play a central role in determining how water interacts with metal oxides, thereby setting important properties of the interface that govern reactivity such as the type and distribution of hydroxyl groups. However, the interconnections between facets and defects remain poorly understood. This limits the usefulness of conventional notions such as that hydroxylation is controlled by metal cation exposure at the surface. Here, using hematite (α-Fe2O3) as a model system, we show how oxygen vacancies overwhelm surface cation-dependent hydroxylation behavior. Synchrotron-based ambient-pressure X-ray photoelectron spectroscopy was used to monitor the adsorption of molecular water and its dissociation to form hydroxyl groups in situ on (001), (012), or (104) facet-engineered hematite nanoparticles. Supported by density functional theory calculations of the respective surface energies and oxygen vacancy formation energies, the findings show how oxygen vacancies are more prone to form on higher energy facets and induce surface hydroxylation at extremely low relative humidity values of 5 × 10-5%. When these vacancies are eliminated, the extent of surface hydroxylation across the facets is as expected from the areal density of exposed iron cations at the surface. These findings help answer fundamental questions about the nature of reducible metal oxide-water interfaces in natural and technological settings and lay the groundwork for rational design of improved oxide-based catalysts.

7.
J Transl Med ; 21(1): 810, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964279

RESUMO

Epitranscriptomic abnormalities, which are highly prevalent in primary central nervous system malignancies, have been identified as crucial contributors to the development and progression of gliomas. RNA epitranscriptomic modifications, particularly the reversible modification methylation, have been observed throughout the RNA cycle. Epitranscriptomic modifications, which regulate RNA transcription and translation, have profound biological implications. These modifications are associated with the development of several cancer types. Notably, three main protein types-writers, erasers, and readers, in conjunction with other related proteins, mediate these epitranscriptomic changes. This review primarily focuses on the role of recently identified RNA methylation modifications in gliomas, such as N6-methyladenosine (m6A), 5-methylcytosine (m5C), N7-methylguanosine (m7G), and N1-methyladenosine (m1A). We delved into their corresponding writers, erasers, readers, and related binding proteins to propose new approaches and prognostic indicators for patients with glioma.


Assuntos
Glioma , Transcriptoma , Humanos , Metilação , RNA/metabolismo , 5-Metilcitosina/metabolismo , Glioma/genética
8.
Chem Rev ; 121(13): 8161-8233, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34143612

RESUMO

Iron (Fe) is the fourth most abundant element in the earth's crust and plays important roles in both biological and chemical processes. The redox reactivity of various Fe(II) forms has gained increasing attention over recent decades in the areas of (bio) geochemistry, environmental chemistry and engineering, and material sciences. The goal of this paper is to review these recent advances and the current state of knowledge of Fe(II) redox chemistry in the environment. Specifically, this comprehensive review focuses on the redox reactivity of four types of Fe(II) species including aqueous Fe(II), Fe(II) complexed with ligands, minerals bearing structural Fe(II), and sorbed Fe(II) on mineral oxide surfaces. The formation pathways, factors governing the reactivity, insights into potential mechanisms, reactivity comparison, and characterization techniques are discussed with reference to the most recent breakthroughs in this field where possible. We also cover the roles of these Fe(II) species in environmental applications of zerovalent iron, microbial processes, biogeochemical cycling of carbon and nutrients, and their abiotic oxidation related processes in natural and engineered systems.

9.
Environ Toxicol ; 38(3): 591-603, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36370150

RESUMO

OBJECTIVE: Environmental contaminants such as cadmium (Cd) may have a deleterious impact on sperm and reduce male fertility by compromising the blood-testis barrier (BTB). Hence, the effects of the traditional Chinese medicine Qiangjing tablet (QJP) on sperm quality and BTB alterations induced by Cd in mouse testes were examined. METHODS: Adult KM mice challenged with Cd chloride were examined, QJP was administered to mice as an oral drug by gavage, and the experiments lasted 2 weeks. Testicular and epididymal weights, sperm quality, anti-sperm antibodies (AsAb), hormone levels, and histology were evaluated. Changes in the levels of N-cadherin, occludin, ZO-1, claudin-11, F-actin, and ß-tubulin and their mRNAs were evaluated. The effects of QJP on the PI3K/Akt/Rictor pathway were evaluated. RESULTS: CdCl2 decreased reproductive organ weight, sperm quality, and testosterone (T) levels; increased AsAb, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels; induced structural damage in testicles with BTB disruption; increased BTB permeability; and decreased N-cadherin, occludin, ZO-1, claudin-11, F-actin, and ß-tubulin expression. After treatment, QJP blocked the effects of Cd on reproductive organ weight, sperm quality, and T; mitigated germinal epithelium compartment alterations; decreased AsAb, FSH, and LH levels; and preserved BTB ultrastructure and function. In addition, QJP induced increases in N-cadherin, occludin, ZO-1, claudin-11, F-actin, and ß-tubulin levels and the expression of their mRNAs through the PI3K/Akt/Rictor pathway. After the application of JRAB2011, the levels of a specific mTORC2 suppressor, Rictor, and the BTB-protective effect of QJP were greatly reduced. CONCLUSIONS: We demonstrated the effect of QJP against Cd-induced damage to the BTB, and the results indicate that QJP may play a significant role in opposing the effects of Cd through the PI3K/Akt/Rictor pathway.


Assuntos
Barreira Hematotesticular , Fosfatidilinositol 3-Quinases , Camundongos , Masculino , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cádmio/metabolismo , Actinas/metabolismo , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/farmacologia , Ocludina/metabolismo , Medicina Tradicional Chinesa , Testículo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Caderinas/metabolismo , Hormônio Foliculoestimulante/metabolismo , Claudinas/metabolismo , Espermatogênese
10.
Molecules ; 28(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36838720

RESUMO

In order to explore the effects of different pretreatment methods on the ultrasonic far-infrared synergistic drying characteristics and quality of wolfberry, the bioactive components (polysaccharide, total phenol, total flavonoids, and antioxidants), the quality characteristics (rehydration ratio, color, vitamin C content, and betaine content), and the microstructure of the dried products were used as evaluation indices to test wolfberry treated by five different pretreatments (hot blanching; candied pretreatment; NaOH solution treatment; NaCl solution treatment; and Na2CO3 solution treatment). The results showed that hot blanching pretreatment improved the drying rate and shortened the drying time, and that the vitamin C content of dried products pretreated by hot blanching (92.56 mg/100 g) was higher than that of dried products pretreated by other methods. All five pretreatment methods increased the contents of the total phenols, vitamin C, and betaine of wolfberry. Wolfberry treated by candied pretreatment had lower color differences and higher contents of polysaccharide (0.83 g/g), total phenol (9.26 mg/g), and total flavonoids (2.61 mg/g) than wolfberry treated by the other pretreatment methods. Wolfberry pretreated by NaCl solution had the strongest antioxidant capacity (65.01%). Wolfberry pretreated by Na2CO3 solution had the highest betaine content (3.24%). The observation of the microstructure of the dried products revealed that hot blanching caused the most damage to wolfberry, while the candied pretreatment was less destructive to the tissue cells of wolfberry. On the whole, the dried wolfberry products obtained by the candied pretreatment were of a better quality than products obtained by the other pretreatment methods.


Assuntos
Lycium , Lycium/química , Ultrassom , Fenol , Betaína , Cloreto de Sódio , Antioxidantes/química , Ácido Ascórbico/química , Dessecação/métodos , Fenóis , Flavonoides , Polissacarídeos
11.
Molecules ; 28(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513468

RESUMO

Ultrasonic (US) maltreatment was performed before the vacuum far-infrared drying (VFID) of Codonopsis pilosula (CP) slices to investigate the effects of different US parameters on the drying characteristics and nutrients of CP slices. The grey correlation method with relative correlation degree (ri) as the evaluation measure was used to construct a model for the evaluation of the pretreatment quality of CP and to determine the optimal pretreatment conditions. The results showed that with the increase in US frequency and power, the drying rate increased. Under the conditions of US power of 180 W, frequency of 60 kHz and a pre-treatment time of 30 min, the drying time reduced by 28.6%. The contents of polysaccharide and syringin in dried CP slices pretreated by US increased by 14.7% and 62.0%, respectively, compared to the non-pre-treated samples, while the total flavonoid content decreased by 10.0%. In terms of colour, pretreatment had a certain protective effect on the red colour of dried products. The highest relative correlation (0.574) and the best overall quality of performance were observed at 180 W, 60 kHz and 30 min. Overall, US technology is suitable for the pretreatment processing of CP, which is of great significance to the drying of CP.


Assuntos
Codonopsis , Ultrassom , Cinética , Dessecação/métodos , Vácuo
12.
Pharm Biol ; 61(1): 271-280, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36655371

RESUMO

CONTEXT: Therapeutic effects of Qiangjing tablets (QJT) on sperm vitality and asthenozoospermia (AZS) have been confirmed. However, the mechanism of action remains unclear. OBJECTIVE: This study investigates the effects of QJT on AZS and the underlying mechanism of action. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were randomly divided into six groups: Control, ORN (ornidazole; 200 mg/kg), ORN + QJT-low (0.17 g/mL), ORN + QJT-middle (0.33 g/mL), ORN + QJT-high (0.67 g/mL), and ORN + QJT + Radicicol (0.67 g/mL QJT and 20 mg/kg radicicol) groups. Pathological evaluation and analysis of mitophagy were conducted by H&E staining and transmission electron microscopy, respectively. Reactive oxygen species were detected by flow cytometry. Protein expression was determined by Western blotting. RESULTS: QJT significantly improved ORN-treated sperm motility and kinematic parameters, as well as the pathological symptoms of testicular and epididymal tissues. In particular, QJT mitigated impaired mitochondrial morphology, and increased the PHB, Beclin-1, LC3-II protein, and ROS levels (p < 0.05), and reduced the protein expression levels of LC3-I and p62 (p < 0.05). Mechanistically, QJT antagonized the downregulation of SCF and Parkin protein levels (p < 0.05). Furthermore, QJT significantly increased the protein expressions levels of LKB1, AMPKα, p-AMPKα, ULK1 and p-ULK1 (p < 0.05). The ameliorative effect of QJT on pathological manifestations, mitochondrial morphology, and the expressions of mitophagy and mitochondrial ubiquitination-related proteins was counteracted by radicicol. DISCUSSION AND CONCLUSIONS: QJT improved AZS via mitochondrial ubiquitination and mitophagy mediated by the LKB1/AMPK/ULK1 signaling pathway. Our study provides a theoretical basis for the treatment of AZS and male infertility.


Assuntos
Astenozoospermia , Medicamentos de Ervas Chinesas , Animais , Masculino , Ratos , Proteínas Quinases Ativadas por AMP , Astenozoospermia/tratamento farmacológico , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Medicamentos de Ervas Chinesas/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/uso terapêutico , Mitofagia , Ratos Sprague-Dawley , Sêmen , Motilidade dos Espermatozoides , Comprimidos/uso terapêutico , Ubiquitinação
13.
BMC Endocr Disord ; 22(1): 189, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869471

RESUMO

BACKGROUND: With the deepening of social aging, the incidence rate of osteoporosis and diabetes continues to rise. More and more clinical studies show that diabetes is highly correlated with osteoporosis. Diabetes osteoporosis is considered as a metabolic bone disease of diabetes patients. This study aims to explore the role and mechanism of metformin (Met) in diabetic osteoporosis. METHODS: Mouse MC3T3-E1 cells were treated with Met (0.5 mM) and exposed to high glucose (HG, 35 mM). The cells were cultured in an osteogenic medium for osteogenic differentiation, and the cell proliferation ability was determined using Cell Counting Kit-8; Alkaline phosphatase (ALP) activity detection and alizarin red staining were utilized to evaluate the effect of Met on MC3T3-E1 osteogenic differentiation. Western blot was used to detect the expressions of osteogenesis-related proteins (Runx2 and OCN) as well as Wnt/ß-catenin signaling pathway-related proteins in MC3T3-E1 cells. RESULTS: HG inhibited proliferation and calcification of MC3T3-E1 cells, down-regulated ALP activity, and the expression of Runx2 and OCN in MC3T3-E1 cells. Meanwhile, the activity of the Wnt/ß-catenin signaling pathway was inhibited. Met treatment was found to significantly stimulate the proliferation and calcification of MC3T3-E1 cells under HG conditions, as well as increase the ALP activity and the protein expression level of Runx2 and OCN in the cells. As a result, osteogenic differentiation was promoted and osteoporosis was alleviated. Apart from this, Met also increased the protein expression level of Wnt1, ß-catenin, and C-myc to activate the Wnt/ß-catenin signaling pathway. CONCLUSION: Met can stimulate the proliferation and osteogenic differentiation of MC3T3-E1 cells under HG conditions. Met may also treat diabetic osteoporosis through Wnt/ß-catenin activation.


Assuntos
Diabetes Mellitus , Metformina , Osteoporose , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/farmacologia , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Osteoblastos , Osteogênese , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , beta Catenina/farmacologia
14.
Sensors (Basel) ; 22(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35062643

RESUMO

The target recognition algorithm is one of the core technologies of Zanthoxylum pepper-picking robots. However, most existing detection algorithms cannot effectively detect Zanthoxylum fruit covered by branches, leaves and other fruits in natural scenes. To improve the work efficiency and adaptability of the Zanthoxylum-picking robot in natural environments, and to recognize and detect fruits in complex environments under different lighting conditions, this paper presents a Zanthoxylum-picking-robot target detection method based on improved YOLOv5s. Firstly, an improved CBF module based on the CBH module in the backbone is raised to improve the detection accuracy. Secondly, the Specter module based on CBF is presented to replace the bottleneck CSP module, which improves the speed of detection with a lightweight structure. Finally, the Zanthoxylum fruit algorithm is checked by the improved YOLOv5 framework, and the differences in detection between YOLOv3, YOLOv4 and YOLOv5 are analyzed and evaluated. Through these improvements, the recall rate, recognition accuracy and mAP of the YOLOv5s are 4.19%, 28.7% and 14.8% higher than those of the original YOLOv5s, YOLOv3 and YOLOv4 models, respectively. Furthermore, the model is transferred to the computing platform of the robot with the cutting-edge NVIDIA Jetson TX2 device. Several experiments are implemented on the TX2, yielding an average time of inference of 0.072, with an average GPU load in 30 s of 20.11%. This method can provide technical support for pepper-picking robots to detect multiple pepper fruits in real time.


Assuntos
Robótica , Zanthoxylum , Algoritmos , Meio Ambiente , Projetos de Pesquisa
15.
Environ Sci Technol ; 55(1): 677-688, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33351596

RESUMO

The expression of specific crystal facets in different nanostructures is known to play a vital role in determining the sensitivity toward the photodegradation of organics, which can generally be ascribed to differences in surface structure and energy. Herein, we report the synthesis of hematite nanoplates with controlled relative exposure of basal (001) and edge (012) facets, enabling us to establish direct correlation between the surface structure and the photocatalytic degradation efficiency of methylene blue (MB) in the presence of hydrogen peroxide. MB adsorption experiments showed that the capacity on (001) is about three times larger than on (012). Density functional theory calculations suggest the adsorption energy on the (001) surface is 6.28 kcal/mol lower than that on the (012) surface. However, the MB photodegradation rate on the (001) surface is around 14.5 times faster than on the (012) surface. We attribute this to a higher availability of the photoelectron accepting surface Fe3+ sites on the (001) facet. This facilitates more efficient iron valence cycling and the heterogeneous photo-Fenton reaction yielding MB-oxidizing hydroxyl radicals at the surface. Our findings help establish a rational basis for the design and optimization of hematite nanostructures as photocatalysts for environmental remediation.


Assuntos
Compostos Férricos , Azul de Metileno , Luz , Fotólise
16.
Zhonghua Nan Ke Xue ; 26(2): 118-122, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33346413

RESUMO

OBJECTIVE: To study the correlation between the brain regional homogeneity (ReHo) features and the clinical characteristics of the patients with psychogenic erectile dysfunction (pED). METHODS: Using IIEF-5 and the Self-Esteem and Relationship (SEAR) questionnaire, we evaluated the erectile function and psychosocial status of 32 pED patients and 28 healthy male subjects. Then, we compared the regional brain activity between the patients and healthy controls by resting-state functional magnetic resonance imaging (RS-fMRI) and the ReHo method, analyzed the correlation of the ReHo value of the altered brain regions with the results of IIEF-5 and SEAR questionnaire investigation, and explored the relationship between the ReHo features and the symptoms of the pED patients. RESULTS: Compared with the healthy male subjects, the pED patients obtained significantly lower IIEF-5 scores (22.21 ± 0.98 vs 13.97 ± 3.60, P < 0.01) and SEAR scores (61.92 ± 3.73 vs 37.58 ± 7.96, P < 0.01), a higher ReHo value of the left lateral cerebellum, and a lower ReHo value of the right precentral gyrus. The ReHo value of the left lateral cerebellum was correlated negatively with the IIEF-5 scores (r= -0.51, P < 0.01) and SEAR scores (r = -0.54, P < 0.01), while that of the right precentral gyrus positively with the IIEF-5 scores (r = 0.57, P < 0.01) and SEAR scores (r = 0.66, P < 0.01). CONCLUSIONS: Patients with pED had lateral cerebellum-mediated abnormal sensory integration and precentral gyrus-related dysfunction of motor imagery and motor execution.


Assuntos
Encéfalo/diagnóstico por imagem , Disfunção Erétil/psicologia , Estudos de Casos e Controles , Cerebelo/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino
17.
Zhonghua Nan Ke Xue ; 26(8): 740-744, 2020 Aug.
Artigo em Zh | MEDLINE | ID: mdl-33377738

RESUMO

OBJECTIVE: To study the effect of Qiangjing Tablets (QJT) on the secretion of the inflammatory cytokines IL-1ß and TNF-ɑ from Sertoli cells in infertile mice based on the microenvironment of spermatogenesis. METHODS: We isolated and cultured mouse Sertoli cells, established the model of Ureaplasma urealyticum (UU) infection in the cells, and treated the cells with QJT at the concentrations of 2.5%, 5% and 10% in the serum. After modeling, we determined the contents of IL-1ß and TNF-ɑ in the supernatant of the cells by ELISA and examined the effect of QJT on the secretion of the inflammatory factors from the Sertoli cells by analyzing the dose-effect and time-effect relationships of the drug. RESULTS: In comparison with the blank control, the UU-infected Sertoli cells showed significantly increased secretion of IL-1ß and TNF-ɑ (P < 0.05), the former reaching the peak value in 12 hours and the latter in 24 hours, followed by a downward trend. The secretion of IL-1ß was remarkably inhibited in the 5% and 10% QJT groups (P < 0.05) and that of TNF- ɑ in the 10% QJT group compared with those in the UU infection model group (P < 0.05). CONCLUSIONS: The secretion of IL-1ß and TNF-ɑ is significantly increased in the UU-infected Sertoli cells, and that of IL-1ß negatively correlated with time. QJT-containing serum can inhibit the secretion of IL-1ß and TNF-ɑ from Sertoli cells, and the inhibitory effect of IL-1 ß is most significant at 5% and 10% and that of TNF- ɑ at 10%.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Interleucina-1beta/metabolismo , Células de Sertoli/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Células de Sertoli/metabolismo , Comprimidos
18.
Inorg Chem ; 58(24): 16727-16735, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31755255

RESUMO

Nanostructure engineering of hematite is a promising strategy to overcome its performance limitations as a photodegradation catalyst for organic dyes or toxic organic chemicals. Precise control of exposed facets plays a vital role as an optimization strategy. Although great progress has been made in the synthesis of different crystal morphologies, design principles remain ad hoc, awaiting systematic control of facet expression within a clean synthesis protocol yielding versatile results. Herein, we report a simple method that enables precise morphology control to synthesize 2D hexagonal hematite nanosheets from two-line ferrihydrite. Nanosheet sizes and facet proportions were successfully tuned by changing the pH, the ratio of solvent ethanol to water, and the concentration of FeIII ions. The growth mechanism appears to involve a combination of ferrihydrite solid-state transformation and assembly into hematite, followed by an ion-by-ion growth that perfects the surface terminations. The finding helps to establish a rational basis for the design and optimization of hematite nanostructures.

19.
Environ Sci Technol ; 53(17): 10197-10207, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31397154

RESUMO

Hematite nanoparticles are abundant in the photic zone of aquatic environments, where they play a prominent role in photocatalytic transformations of bound organics. Here, we examine the photocatalytic degradation of rhodamine B by visible light using two different structurally well-defined hematite nanoparticle morphologies. In addition to detailed solid characterization and aqueous kinetics measurements, we also exploit species-selective scavengers in electron paramagnetic resonance spectroscopy to sequester specific reaction channels and thereby assess their impact. The photodegradation rates for nanoplates dominated by {001} facets and nanocubes dominated by {012} facets were 0.13 and 0.7 h-1, respectively, and the turnover frequencies for the active sites on {001} and {012} were 7.89 × 10-3 and 3.07× 10-3 s-1, yielding apparent activation energies of 17.13 and 24.94 kcal/mol within the energetic span model, respectively. Facet-specific differences appear to be directly not linked with the simple aerial cation site density but instead with their extent of undercoordination. By establishing this linkage, the findings lay a foundation for predicting the photocatalytic degradation efficiency for the myriad of possible hematite nanoparticle morphologies and more broadly help unveil key reactions at the interface that may govern photocatalytic organic transformations in natural and engineered aquatic environments.


Assuntos
Compostos Férricos , Nanopartículas , Catálise , Fotólise
20.
Zhonghua Nan Ke Xue ; 24(5): 436-441, 2018 May.
Artigo em Zh | MEDLINE | ID: mdl-30171760

RESUMO

OBJECTIVE: To investigate the effects of Qiangjing Tablets (QJT) on sperm quality and the MAPK signaling pathway in the SD rat model of asthenospermia (AS). METHODS: A total of 100 male SD rats were randomly divided into five groups of equal number, blank control, AS model control, high-dose QJT, medium-dose QJT, and low-dose QJT. All the rats were intragastrically administered ORN at 200 mg/kg/d for establishment of the AS model except those in the blank control group, which were given 1% CMC sodium solution at 1 ml/100 g by gavage. Meanwhile the animals of the high-, medium-, and low-dose QJT groups were gavaged with QJT at 6700, 3300 and 1700 mg/kg/d, respectively, qd 6 days a week for 20 days. Then the testis issue and the apoptosis of the testicular cells were observed under the electron microscope, the expression of vimentin in the testis was determined with the immunohistochemical SP method, that of ERK1/2 detected by Western blot, and the concentration of TGF-ß1 in the semen measured by ELISA. RESULTS: The AS model controls showed round nuclei of spermatocytes, homogeneously distributed chromatins, broken or lost mitochondria, and expanded rough endoplasmic reticulum in the testis tissue. In comparison, the rats of the high-, medium-, and low-dose QJT groups exhibited round nuclei of spermatocytes, homogeneously distributed chromatins, and well-structured mitochondria, rough endoplasmic reticulum and ribosome, which were all similar those of the blank controls. Compared with the blank controls, the AS model rats manifested significantly increased expressions of ERK1/2 (1.00 ± 0.00 vs 1.26 ± 0.10, P<0.01) and vimentin (0.16 ± 0.01 vs 0.17 ± 0.01, P<0.01) and apoptosis rate of cells in the testis tissue (ï¼»9.20 ± 3.07ï¼½ vs ï¼»42.20 ± 9.17ï¼½ %, P<0.01), but decreased level of TGF-ß1 in the semen (ï¼»627.67 ± 26.07ï¼½ vs ï¼»566.73 ± 68.44ï¼½ ng/ml, P<0.05). In comparison with the model controls, the rats of the high- and medium- -dose QJT groups presented remarkably down-regulated expressions of ERK1/2 (1.26 ± 0.10 vs 1.14 ± 0.08, P<0.01; 1.26 ± 0.10 vs 1.18 ± 0.05, P<0.05) and vimentin (0.17 ± 0.01 vs 0.16 ± 0.01, P<0.01; 0.17 ± 0.01 vs 0.17 ± 0.09, P<0.05) and decreased rate of cell apoptosis (ï¼»42.20 ± 9.17ï¼½ vs ï¼»21.60 ± 5.94ï¼½ %, P<0.01; ï¼»42.20 ± 9.17ï¼½ vs ï¼»33.95 ± 6.39ï¼½ %, P<0.05). The concentration of TGF-ß1 in the semen was markedly lower in the high-dose QJT than in the AS model control group (ï¼»621.78 ± 30.80ï¼½ vs ï¼»566.73 ± 68.44ï¼½ ng/ml, P < 0.05). CONCLUSIONS: Qiangjing Tablets could improve semen quality in asthenospermia rats by acting against oxidative stress.


Assuntos
Astenozoospermia/enzimologia , Medicamentos de Ervas Chinesas/farmacologia , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Análise do Sêmen , Animais , Apoptose , Masculino , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sêmen , Transdução de Sinais , Espermatozoides , Testículo/metabolismo , Testículo/ultraestrutura , Fator de Crescimento Transformador beta1/metabolismo , Vimentina/metabolismo
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