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1.
Small ; 19(39): e2302387, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37231567

RESUMO

Van der Waals (vdW) heterostructures combining layered ferromagnets and other 2D crystals are promising building blocks for the realization of ultracompact devices with integrated magnetic, electronic, and optical functionalities. Their implementation in various technologies depends strongly on the development of a bottom-up scalable synthesis approach allowing for realizing highly uniform heterostructures with well-defined interfaces between different 2D-layered materials. It is also required that each material component of the heterostructure remains functional, which ideally includes ferromagnetic order above room temperature for 2D ferromagnets. Here, it is demonstrated that the large-area growth of Fe5- x GeTe2 /graphene heterostructures is achieved by vdW epitaxy of Fe5- x GeTe2 on epitaxial graphene. Structural characterization confirms the realization of a continuous vdW heterostructure film with a sharp interface between Fe5- x GeTe2 and graphene. Magnetic and transport studies reveal that the ferromagnetic order persists well above 300 K with a perpendicular magnetic anisotropy. In addition, epitaxial graphene on SiC(0001) continues to exhibit a high electronic quality. These results represent an important advance beyond nonscalable flake exfoliation and stacking methods, thus marking a crucial step toward the implementation of ferromagnetic 2D materials in practical applications.

2.
Glob Chang Biol ; 29(10): 2655-2668, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36794561

RESUMO

Numerous insects including pests and beneficial species undertake windborne migrations over hundreds of kilometers. In East Asia, climate-induced changes in large-scale atmospheric circulation systems are affecting wind-fields and precipitation zones and these, in turn, are changing migration patterns. We examined the consequences in a serious rice pest, the brown planthopper (BPH, Nilaparvata lugens) in East China. BPH cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The East Asian summer monsoon, characterized by abundant rainfall and southerly winds, is of critical importance for these northward movements. We analyzed a 42-year dataset of meteorological parameters and catches of BPH from a standardized network of 341 light-traps in South and East China. We show that south of the Yangtze River during summer, southwesterly winds have weakened and rainfall increased, while the summer precipitation has decreased further north on the Jianghuai Plain. Together, these changes have resulted in shorter migratory journeys for BPH leaving South China. As a result, pest outbreaks of BPH in the key rice-growing area of the Lower Yangtze River Valley (LYRV) have declined since 2001. We show that these changes to the East Asian summer monsoon weather parameters are driven by shifts in the position and intensity of the Western Pacific subtropical high (WPSH) system that have occurred during the last 20 years. As a result, the relationship between WPSH intensity and BPH immigration that was previously used to predict the size of the immigration to the LYRV has now broken down. Our results demonstrate that migration patterns of a serious rice pest have shifted in response to the climate-induced changes in precipitation and wind pattern, with significant consequences for the population management of migratory pests.


Assuntos
Hemípteros , Oryza , Tempo (Meteorologia) , China , Animais
3.
Angew Chem Int Ed Engl ; 62(27): e202303296, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37113018

RESUMO

The study of heterogeneous reactions for enantiomeric processes based on inorganic crystals has been resurgent in recent years. However, the question remains how homochirality develops in nature and chemical reactions. Here, the successful growth of B20 group PdGa single crystals with different chiral lattices enabled us to achieve enantioselective recognition of 3,4-dihydroxyphenylalanine (DOPA) based on a new mechanism, namely orbital angular momentum (OAM) polarization. The orbital textures of PdGa crystals indicate large OAM polarization near the Fermi level and carrying opposite signs. A positive or negative magnetization in the [111] direction is expected depending on the chiral lattice of PdGa crystals. Due to this, the adsorption energies of PdGa crystals and DOPA molecules differ depending on how well the O-2p orbital of DOPA pairs with the Pd-4d orbital of PdGa. The results provide one possible explanation for how chirality arises in nature by providing an enantioselective route with pure inorganic crystals.

4.
J Stroke Cerebrovasc Dis ; 30(2): 105489, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33276305

RESUMO

BACKGROUND: Ischemic stroke is clearly affected by microRNAs (miRNAs) due to dysfunction of their regulatory networks. Our clinical data confirmed decreased miR-221 levels in plasma collected from patients with acute ischemia compared with plasma from healthy controls. Therefore, we further aimed to demonstrate the regulatory mechanisms by which miR-221 exerts its neuroprotective effects in acute ischemic brain injury. METHODS: Middle cerebral artery occlusion (MCAO) was used to establish focal cerebral ischemia in adult male C57BL/6 mice. A miR-221 mimic or a negative mimic control was injected by intracerebroventricular administration 24 h prior to MCAO. After 48 h, cerebral infarction volume and neurological scores were calculated, and to determine the extent of neuroprotection by miR-221, neurobehavioral tests were performed. Quantitative real-time PCR, ELISA, and flow cytometry were also performed to identify the expression of inflammation-related cytokines and chemokines as well as infiltration/activation of various immune cells in the brain. RESULTS: The results showed that MCAO mice treated with a miR-221 mimic exhibited significantly decreased cerebral infarction volume and increased amelioration of behavioral deficits. Moreover, the expression of proinflammatory cytokines (TNF-α, MCP-1, VCAM-1, and IL-6) and chemokines (CCL2 and CCL3) was significantly decreased in the miR-221 mimic-treated group. In addition, the flow cytometry data showed that macrophage infiltration and microglial activation were blocked by miR-221 treatment. CONCLUSION: our results indicate that miR-221 could decrease brain damage in the setting of acute ischemic stroke by inhibiting the proinflammatory response, which furthered our understanding of the molecular basis of miR-221 and provided a new potential therapeutic target for the treatment of ischemic stroke .


Assuntos
Encéfalo/metabolismo , Citocinas/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Mediadores da Inflamação/metabolismo , AVC Isquêmico/metabolismo , MicroRNAs/metabolismo , Idoso , Animais , Encéfalo/patologia , Estudos de Casos e Controles , Citocinas/genética , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Humanos , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/patologia , AVC Isquêmico/genética , AVC Isquêmico/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/sangue , MicroRNAs/genética , Microglia/metabolismo , Microglia/patologia , Fármacos Neuroprotetores/administração & dosagem , Oligonucleotídeos/administração & dosagem , Transdução de Sinais
5.
Exp Mol Pathol ; 115: 104475, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32473154

RESUMO

The transcription factor EB (TFEB) is known for its role in lysosomal biogenesis, and it coordinates this process by driving autophagy and lysosomal gene expression during ischemia. In the present study, we aimed to explore the role of the TFEB-regulated autophagolysosome pathway (ALP) in rats with chronic cerebral ischemia (CCI) that were treated with remote ischemic postconditioning (RIPC). A modified 2-vessel occlusion (2-VO) method was utilized to establish the CCI rat model, and the CCI rats were identified by the Morris water maze test and histological staining. After the CCI rats were treated with RIPC, the damage to the rat cortex and hippocampal tissues and the status of the ALP were determined. Western blot analysis and immunofluorescence assays were performed to observe the nuclear translocation of TFEB. The rats were injected with TFEB siRNA via the lateral ventricle to investigate the effect of TFEB siRNA on the RIPC-treated CCI rats. The results suggested that RIPC of the CCI rats alleviated nerve injury, induced TFEB translocation into the nucleus, upregulated autophagy-related protein expression, and activated ALP machinery. Furthermore, TFEB siRNA decreased the levels of TFEB and impaired the neuroprotective effects of RIPC on the CCI rats. Collectively, we highlighted that RIPC attenuates damage in CCI rats via the activation of the TFEB-mediated ALP.


Assuntos
Autofagossomos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Isquemia Encefálica/patologia , Pós-Condicionamento Isquêmico , Lisossomos/metabolismo , Regulação para Cima , Animais , Autofagossomos/ultraestrutura , Encéfalo/patologia , Encéfalo/ultraestrutura , Doença Crônica , Regulação para Baixo , Lisossomos/ultraestrutura , Masculino , Tecido Nervoso/lesões , Tecido Nervoso/patologia , RNA Interferente Pequeno/metabolismo , Ratos Wistar
6.
Phys Chem Chem Phys ; 19(17): 10898-10904, 2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28401238

RESUMO

Resistive switching in metal-insulator-metal nanosctructures is being intensively studied for nonvolatile memory applications. Here, we report unipolar resistive switching in Pt/MgO/Ta/Ru structures, with a 30 nm oxide barrier. A forming process was needed to initiate the resistive switching, which was then observed for all Set and Reset voltage polarity combinations. We studied the influence of the voltage polarity on the variability of the Set/Reset voltages and ON/OFF resistances and revealed the importance of a thin TaOx layer working as an oxygen revervoir for resistive switching. The mechanism behind this phenomenon can be understood in terms of conductive filaments formation/rupture with a contribution from Joule heating. Resistance change is thus caused by a voltage-driven oxygen vacancy motion in the MgO layer and a filament model was proposed for each polarity mode. A OFF/ON resistance ratio of at least 2 orders of magnitude was obtained with resistive states stable up to 104 s. Our results open the prospect to improve switching performance in other resistive switching systems, by proving a better understanding of the differences between operation modes.

7.
J Arthroplasty ; 32(9): 2706-2711, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28483213

RESUMO

BACKGROUND: To translate and cross-culturally adapt the University of California at Los Angeles (UCLA) activity score into a simplified Chinese version (UCLA-C) and evaluate the reliability and validity of the UCLA-C for patients with both knee arthroscopy and total knee arthroplasty. METHODS: Cross-cultural adaptation was performed according to the internationally recognized guidelines of the American Academy of Orthopaedic Surgeons Outcome Committee. A total of 200 participants (100 arthroscopy and 100 total knee arthroplasty) were recruited in this study. An intraclass correlation coefficient (ICC) was used to determine reliability. Construct validity was analyzed by evaluating the correlations between UCLA-C and the Tegner activity score, Knee Injury and Osteoarthritis Outcome Score, and the short-form (36) health survey. RESULTS: The original version of the UCLA activity score was cross-culturally well adapted and translated into simplified Chinese. UCLA-C was found to have excellent reliability in both arthroscopy (ICC = 0.984, 95% confidence interval 0.976-0.989) and arthroplasty (ICC = 0.946, 95% confidence interval 0.920-0.964). Absolute reliability as evaluated by minimal detectable change was 0.789 and 0.837 for both arthroscopy and arthroplasty groups. Moderate to high correlations between UCLA-C and Tegner activity score (0.799, P < .001); Knee Injury and Osteoarthritis Outcome Score (0.449-0.715, P < .001); and Physical Functioning, Pain, General Health, and Social Functioning (0.549-0.746, P < .001) subdomains of short-form (36) health survey were observed. CONCLUSION: UCLA-C was demonstrated to have excellent acceptability, reliability, and validity in both arthroscopy and arthroplasty, and could be recommended for patients in mainland China.


Assuntos
Artroplastia do Joelho , Artroscopia , Comparação Transcultural , Artropatias/cirurgia , Articulação do Joelho/cirurgia , Adolescente , Adulto , Idoso , Povo Asiático , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Tradução , Adulto Jovem
9.
Environ Sci Technol ; 50(17): 9034-43, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27502019

RESUMO

The hydrodynamic and structural properties of Microcystis extracellular polymeric substances (EPS) in electrolytes with different valences and ionic strengths were investigated via using dynamic light scattering, the fluorescence excitation emission matrix coupled with parallel factor (EEM-PARAFAC) analysis, two-dimensional correlation spectroscopy (2D-COS), and cryogenic transmission electron microscopy (Cryo-TEM). The hydrodynamic diameters of EPS colloids exhibited no variation for monovalent NaCl but a substantial increase for divalent CaCl2 and MgCl2. However, the negative electrophoretic mobilities for all complexes indicated that charge neutralization would not be the main mechanism for EPS aggregation. Application of EEM-PARAFAC and 2D-Fourier transform infrared (FTIR)-COS revealed obvious electrolyte binding potential with both fluorescent phenolic and aromatic compounds and nonfluorescent polysaccharides. The complexation model showed that divalent Ca(2+) and Mg(2+) exhibited a strong binding capability with phenolic -OH, aromatic C═C, and polysaccharide C-O groups, while the monovalent electrolyte exhibited negligible association with these groups. Such a strong complexation can bridge each individual biomolecule together to form EPS aggregates and Microcystis colonies, as supported by in situ Cryo-TEM and light microscope observation, respectively. Given the increased concentration in natural ecosystems, electrolyte cations, especially divalent cations, would play increased roles in Microcystis bloom formation and thus should be considered.


Assuntos
Lagos , Microcystis/metabolismo , Cátions , Eletrólitos/metabolismo , Polímeros/química
10.
J Headache Pain ; 17(1): 99, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27778243

RESUMO

BACKGROUND: Antioxidants have been proven to weaken hyperalgesia in neuropathic pain. Endogenous antioxidant defense system may have a role in the prevention of hyperalgesia in migraine. In this study, we aimed to evaluate the role of nuclear factor E2-related factor 2/antioxidant response element (Nrf2/ARE) pathway in regulating the activation of the trigeminovascular system (TGVS) and hypersensitivity in nitroglycerin (NTG)-induced hyperalgesia rats. METHODS: The expression levels of Nrf2, HO, HO1, and NQO1 in the trigeminal nucleus caudalis (TNC) were detected by western blot. Immunofluorescence was used to demonstrate the cell-specific localization of Nrf2 in TNC. Sulforaphane, a Nrf2 activator, was administered to NTG-induced rats. Then, the number of c-Fos- and nNOS-immunoreactive neurons in TNC was evaluated using immunofluorescence, and c-Fos and nNOS protein levels were quantified using western blot. Von Frey hair testing was used to evaluate the tactile thresholds of rats at different time points in different groups. RESULTS: Total cellular and nuclear levels of the proteins Nrf2, HO1, and NQO1 were elevated in TNC after NTG injection, and Nrf2 was found to be located in the nucleus and cytoplasm of the neurons. Sulforaphane pretreatment significantly increased the nuclear Nrf2, HO1, and NQO1 levels in TNC. In addition, sulforaphane exposure effectively inhibited the expression of nNOS and c-Fos, reduced the number of nNOS and c-Fos immunoreactive neurons in TNC, and attenuated the tactile thresholds induced by NTG injection. CONCLUSION: Oxidative stress was involved in nitroglycerin-induced hyperalgesia. Activation of the Nrf2/ARE pathway inhibited the activation of TGVS and prevented the induction of hyperalgesia. Sulforaphane might therefore be an effective agent for hyperalgesia. Further studies are needed to discover the underlying mechanisms of the process.


Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Hiperalgesia/metabolismo , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , Núcleo Inferior Caudal do Nervo Trigêmeo/efeitos dos fármacos , Animais , Anticarcinógenos/farmacologia , Heme Oxigenase (Desciclizante)/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/metabolismo , Hiperalgesia/induzido quimicamente , Isotiocianatos/farmacologia , Masculino , Transtornos de Enxaqueca/metabolismo , NAD(P)H Desidrogenase (Quinona)/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/metabolismo , Nitroglicerina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Sulfóxidos , Núcleo Inferior Caudal do Nervo Trigêmeo/metabolismo , Vasodilatadores/farmacologia
11.
Appl Microbiol Biotechnol ; 99(20): 8691-700, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26062534

RESUMO

Expelling heterologous compounds out of hosts by transporters is a potential strategy to enhance product titers in microbial cell factories. In this work, to increase heterologous polyketide 6-deoxyerythronolide B (6dEB, erythromycin precursor) production, tripartite multidrug efflux pumps MacAB-TolC, AcrAB-TolC, MdtEF-TolC, and MexAB-OprM were modulated in a 6dEB production strain. Compared with the control, overexpression of a single component of efflux pumps (except oprM) repressed 6dEB production, but modulation of two components MacA and MacB or the complete pumps MacAB-TolC and MdtEF-TolC significantly improved 6dEB titer by 100 ± 11, 118 ± 54, and 98 ± 12 %, respectively. In addition, to avoid the challenging fine-tuning components of pumps, the transcriptional regulators of efflux pumps were modulated to improve the 6dEB production. Overexpression of RpoH (activator of MdtEF-TolC) and EvgA (activator of EmrKY-TolC and AcrAD-TolC) strongly increased 6dEB titer by 152 ± 54 and 142 ± 85 %, respectively. This is the first report of transporter engineering for improving heterologous polyketide production in Escherichia coli. Our results provide an effective strategy for improving the yield of the heterologous products in chassis cell.


Assuntos
Eritromicina/análogos & derivados , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Engenharia Metabólica/métodos , Policetídeos/metabolismo , Transporte Biológico Ativo , Eritromicina/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
12.
Molecules ; 20(6): 11034-45, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26083037

RESUMO

Chitosan-based active films were developed by incorporation of carvacrol (10 g/L), pomegranate peel extract (PPE, 10 g/L) and carvacrol + PPE (10 g/L of each) and their physical, antioxidant and antimicrobial properties were investigated. Incorporation of carvacrol and carvacrol + PPE into the films significantly decreased the water vapor permeability, tensile strength and percentage of elongation at break. Incorporation of carvacrol, PPE and carvacrol + PPE into the films decreased the transparency, but significantly increased the total phenol content and antioxidant activity. All the films, with the exception of PPE-incorporated film, exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, the antibacterial activity against Staphylococcus aureus of the film incorporated with carvacrol + PPE was moderately higher than that incorporated with carvacrol or PPE alone, suggesting a synergistic action between carvacrol and PPE.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Quitosana/química , Lythraceae/química , Monoterpenos/química , Extratos Vegetais/química , Cimenos , Testes de Sensibilidade Microbiana , Permeabilidade , Fenóis , Resistência à Tração
13.
J Nat Prod ; 77(2): 200-5, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24484201

RESUMO

Eight new glucosylated coumaroyltyramine derivatives, teuvissides A-H (1-8), were isolated from whole plants of Teucrium viscidum. Their structures were elucidated using spectroscopic data and chemical methods. The antihyperglycemic activities of these compounds were evaluated in HepG2 cells and 3T3-L1 adipocytes, and all of the isolates elicited different levels of glucose consumption at a concentration of 2.0 µM. Teuvissides A (1), B (2), and F (6) induced 2.2-, 2.1-, and 2.2-fold changes, respectively, in the levels of glucose consumption in HepG2 cells and 2.5-, 2.1-, and 2.3-fold changes, respectively, in 3T3-L1 adipocytes relative to the basal levels.


Assuntos
Ácidos Cumáricos/isolamento & purificação , Ácidos Cumáricos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Teucrium/química , Tiramina/análogos & derivados , Adipócitos/efeitos dos fármacos , Animais , Ácidos Cumáricos/química , Medicamentos de Ervas Chinesas/química , Glucose/análogos & derivados , Glucose/farmacologia , Glicosídeos/química , Células Hep G2 , Humanos , Hipoglicemiantes/química , Insulina/farmacologia , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Tiramina/química , Tiramina/isolamento & purificação , Tiramina/farmacologia
14.
Chem Pharm Bull (Tokyo) ; 62(5): 472-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24789929

RESUMO

Two new neo-clerodane diterpenoids, teucvisins A and B (1, 2), and three new 19-nor-neoclerodane diterpenoids, teucvisins C-E (3-5), together with ten known constituents (6-15) were isolated from the whole plants of Teucrium viscidum. All the isolates were evaluated for their inhibitory activities of lipopolysaccharide (LPS)-induced nitric oxide production in RAW264.7 macrophages. The results indicated that compounds 11 and 15 showed moderate inhibition with an IC50 value of 21.9 and 22.4 µM, respectively.


Assuntos
Diterpenos Clerodânicos/farmacologia , Macrófagos/efeitos dos fármacos , Teucrium/química , Animais , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/isolamento & purificação , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Relação Estrutura-Atividade
15.
Zhongguo Zhong Yao Za Zhi ; 39(14): 2777-81, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25272514

RESUMO

Distribution channel of Chinese herbal medicines has been changing. From Han to Ming Dynasty, Chinese herbal medicine were mainly trafficked to urban by dealers or farmers; From the Ming Dynasty to the foundation of new China, distribution channels are primarily intermediated with township "bazaar" and national distribution center with fixed place and regularly trading hours. In the planned economy period, the state-owned herbal medicine company was the sole medium with monopoly nature. From the mid1980s to the end of last century, planned economy and market economy have been co-existing. Stepping into 21st century, producing area highlighted in the distribution channels. Presence or absence and rise or fall of different types of distribution market went throughout the changing process of distribution channels, which became an important clue. Changes were motivated by economical consideration of channel subject, which originated from commodity characteristic and social environment changes.


Assuntos
Medicamentos de Ervas Chinesas/economia , Medicamentos de Ervas Chinesas/provisão & distribuição , Cidades , Desenvolvimento Econômico , Marketing
16.
Mol Neurobiol ; 61(8): 4992-5001, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38157120

RESUMO

Neurodegenerative diseases, a group of debilitating disorders, have garnered increasing attention due to their escalating prevalence, particularly among aging populations. Alzheimer's disease (AD) reigns as a prominent exemplar within this category, distinguished by its relentless progression of cognitive impairment and the accumulation of aberrant protein aggregates within the intricate landscape of the brain. While the intricate pathogenesis of neurodegenerative diseases has been the subject of extensive investigation, recent scientific inquiry has unveiled a novel player in this complex scenario-transient receptor potential mucolipin 1 (TRPML1) channels. This comprehensive review embarks on an exploration of the intricate interplay between TRPML1 channels and neurodegenerative diseases, with an explicit spotlight on Alzheimer's disease. It immerses itself in the intricate molecular mechanisms governing TRPML1 channel functionality and elucidates their profound implications for the well-being of neurons. Furthermore, the review ventures into the realm of therapeutic potential, pondering the possibilities and challenges associated with targeting TRPML1 channels as a promising avenue for the amelioration of neurodegenerative disorders. As we traverse this multifaceted terrain of neurodegeneration and the enigmatic role of TRPML1 channels, we embark on a journey that not only broadens our understanding of the intricate machinery governing neuronal health but also holds promise for the development of innovative therapeutic interventions in the relentless battle against neurodegenerative diseases.


Assuntos
Mutação , Doenças Neurodegenerativas , Canais de Potencial de Receptor Transitório , Humanos , Canais de Potencial de Receptor Transitório/metabolismo , Canais de Potencial de Receptor Transitório/genética , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Animais , Mutação/genética , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia
17.
Commun Biol ; 7(1): 781, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38944651

RESUMO

Macrolide antibiotics, pivotal in clinical therapeutics, are confronting resistance challenges mediated by enzymes like macrolide esterases, which are classified into Ere-type and the less studied Est-type. In this study, we provide the biochemical confirmation of EstX, an Est-type macrolide esterase that initially identified as unknown protein in the 1980s. EstX is capable of hydrolyzing four 16-membered ring macrolides, encompassing both veterinary (tylosin, tidipirosin, and tilmicosin) and human-use (leucomycin A5) antibiotics. It uses typical catalytic triad (Asp233-His261-Ser102) from alpha/beta hydrolase superfamily for ester bond hydrolysis. Further genomic context analysis suggests that the dissemination of estX is likely facilitated by mobile genetic elements such as integrons and transposons. The global distribution study indicates that bacteria harboring the estX gene, predominantly pathogenic species like Escherichia coli, Salmonella enterica, and Klebsiella pneumoniae, are prevalent in 74 countries across 6 continents. Additionally, the emergence timeline of the estX gene suggests its proliferation may be linked to the overuse of macrolide antibiotics. The widespread prevalence and dissemination of Est-type macrolide esterase highlight an urgent need for enhanced monitoring and in-depth research, underlining its significance as an escalating public health issue.


Assuntos
Esterases , Esterases/genética , Esterases/metabolismo , Esterases/química , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Macrolídeos/metabolismo , Humanos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Filogenia , Hidrolases/genética , Hidrolases/metabolismo , Hidrolases/química
18.
Front Cell Dev Biol ; 12: 1396890, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983788

RESUMO

Background: The Juan-Bi decoction (JBD) is a classic traditional Chinese medicines (TCMs) prescription for the treatment of rheumatoid arthritis (RA). However, the active compounds of the JBD in RA treatment remain unclear. Aim: The aim of this study is to screen effective compounds in the JBD for RA treatment using systems pharmacology and experimental approaches. Method: Botanical drugs and compounds in the JBD were acquired from multiple public TCM databases. All compounds were initially screened using absorption, distribution, metabolism, excretion, and toxicity (ADMET) and physicochemical properties, and then a target prediction was performed. RA pathological genes were acquired from the DisGeNet database. Potential active compounds were screened by constructing a compound-target-pathogenic gene (C-T-P) network and calculating the cumulative interaction intensity of the compounds on pathogenic genes. The effectiveness of the compounds was verified using lipopolysaccharide (LPS)-induced RAW.264.7 cells and collagen-induced arthritis (CIA) mouse models. Results: We screened 15 potentially active compounds in the JBD for RA treatment. These compounds primarily act on multiple metabolic pathways, immune pathways, and signaling transduction pathways. Furthermore, in vivo and in vitro experiments showed that bornyl acetate (BAC) alleviated joint damage, and inflammatory cells infiltrated and facilitated a smooth cartilage surface via the suppression of the steroid hormone biosynthesis. Conclusion: We screened potential compounds in the JBD for the treatment of RA using systems pharmacology approaches. In particular, BAC had an anti-rheumatic effect, and future studies are required to elucidate the underlying mechanisms.

19.
J Cardiovasc Pharmacol ; 61(5): 355-60, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23188130

RESUMO

Qian Yang He Ji (QYHJ) is a traditional Chinese medicine composed of Digitalis purpurea, Uncaria gambir, Fructus tribuli terrestris, and Ligustrum lucidum. Here, we explored whether combining an antihypertensive angiotensin II receptor blocker (ARB) therapy with QYHJ can improve the arterial functionality of hypertensive patients. One hundred and eight hypertensive patients were randomized into 2 groups; 1 group (n = 53) was treated with ARB and the other group (n = 55) was treated with ARB combined with QYHJ. Each of the 2 groups included 3 subgroups (pure hypertension, hypertension with diabetes, and hypertension with coronary heart disease) and was further divided into patients with and without complications. The cardioankle vascular index and intima-media thickness and pulse pressure were the outcome evaluation parameter. Combined QYHJ and ARB treatment reduced the values of cardioankle vascular index, systolic blood pressure, diastolic blood pressure, and pulse pressure to significantly lower levels than ARB treatment alone did in hypertension patients after 6 months of treatment. ARB improves hypertension, but a combined QYHJ treatment can additionally ameliorate the arterial functionality not only in solely hypertensive patients but also in hypertensive patients with diabetes and coronary heart disease complications. QYHJ coapplication might be a choice to further improve the arterial functionality during an ARB hypertension treatment.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Espessura Intima-Media Carotídea , Medicamentos de Ervas Chinesas/uso terapêutico , Hipertensão/tratamento farmacológico , Rigidez Vascular/efeitos dos fármacos , Idoso , Artérias/efeitos dos fármacos , Artérias/fisiopatologia , Quimioterapia Combinada , Eletrocardiografia , Feminino , Frequência Cardíaca , Humanos , Hipertensão/fisiopatologia , Masculino , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Inquéritos e Questionários
20.
Micromachines (Basel) ; 14(2)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36838128

RESUMO

The preparation of micro/nano periodic surface structures using femtosecond laser machining technology has been the academic frontier and hotspot in recent years. The formation and evolution of micro/nano periodic ripples were investigated on 2205 stainless steel machined by femtosecond laser. Using single spot irradiation with fixed laser fluences and various pulse numbers, typical ripples, including nano HSFLs (‖), nano LSFLs (⟂), nano HSFLs (⟂) and micro grooves (‖), were generated one after another in one test. The morphologies of the ripples were analyzed, and the underlying mechanisms were discussed. It was found that the nano holes/pits presented at all stages could have played a key role in the formation and evolution of micro/nano periodic ripples. A new kind of microstructure, named the pea pod-like structure here, was discovered, and it was suggested that the formation and evolution of the micro/nano periodic ripples could be well explained by the pea pod-like structure model.

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