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1.
Nucleic Acids Res ; 51(D1): D1397-D1404, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36134718

RESUMO

Numerous studies have shown that RNA plays an important role in the occurrence and development of diseases, and RNA-disease associations are not limited to noncoding RNAs in mammals but also exist for protein-coding RNAs. Furthermore, RNA-associated diseases are found across species including plants and nonmammals. To better analyze diseases at the RNA level and facilitate researchers in exploring the pathogenic mechanism of diseases, we decided to update and change MNDR v3.0 to RNADisease v4.0, a repository for RNA-disease association (http://www.rnadisease.org/ or http://www.rna-society.org/mndr/). Compared to the previous version, new features include: (i) expanded data sources and categories of species, RNA types, and diseases; (ii) the addition of a comprehensive analysis of RNAs from thousands of high-throughput sequencing data of cancer samples and normal samples; (iii) the addition of an RNA-disease enrichment tool and (iv) the addition of four RNA-disease prediction tools. In summary, RNADisease v4.0 provides a comprehensive and concise data resource of RNA-disease associations which contains a total of 3 428 058 RNA-disease entries covering 18 RNA types, 117 species and 4090 diseases to meet the needs of biological research and lay the foundation for future therapeutic applications of diseases.


Assuntos
Bases de Dados Genéticas , Doença , RNA , Animais , Mamíferos/genética , Neoplasias/genética , RNA/genética , RNA Longo não Codificante/genética , RNA não Traduzido , Doença/genética
2.
Clin Immunol ; 261: 109929, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38331303

RESUMO

Previous studies have shown that epigenetic factors are involved in the occurrence and development of rheumatoid arthritis (RA). However, the role of N6-methyladenosine (m6A) methylation in RA has not been determined. The aim of this study was to investigate the role and regulatory mechanisms of hypoxia-induced expression of the m6A demethylase alkB homolog 5 (ALKBH5) in RA fibroblast-like synoviocytes (FLSs). Synovial tissues were collected from RA and osteoarthritis (OA) patients, and RA FLSs were obtained. ALKBH5 expression in RA FLSs and collagen-induced arthritis (CIA) model rats was determined using quantitative reverse transcription-PCR (qRT-PCR), western blotting and immunohistochemistry (IHC). Using ALKBH5 overexpression and knockdown, we determined the role of ALKBH5 in RA FLS aggression and inflammation. The role of ALKBH5 in RA FLS regulation was explored using m6A-methylated RNA sequencing and methylated RNA immunoprecipitation coupled with quantitative real-time PCR. The expression of ALKBH5 was increased in RA synovial tissues, CIA model rats and RA FLSs, and a hypoxic environment increased the expression of ALKBH5 in FLSs. Increased expression of ALKBH5 promoted the proliferation and migration of RA-FLSs and inflammation. Conversely, decreased ALKBH5 expression inhibited the migration of RA-FLSs and inflammation. Mechanistically, hypoxia-induced ALKBH5 expression promoted FLS aggression and inflammation by regulating CH25H mRNA stability. Our study elucidated the functional roles of ALKBH5 and mRNA m6A methylation in RA and revealed that the HIF1α/2α-ALKBH5-CH25H pathway may be key for FLS aggression and inflammation. This study provides a novel approach for the treatment of RA by targeting the HIF1α/2α-ALKBH5-CH25H pathway.


Assuntos
Adenina/análogos & derivados , Agressão , Artrite Reumatoide , Humanos , Ratos , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Inflamação/metabolismo , Hipóxia , Fibroblastos/metabolismo , Proliferação de Células , Células Cultivadas , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
3.
J Autoimmun ; 146: 103214, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38648706

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease characterized by joint inflammation and bone damage, that not only restricts patient activity but also tends to be accompanied by a series of complications, seriously affecting patient prognosis. Peroxisome proliferator-activated receptor gamma (PPARG), a receptor that controls cellular metabolism, regulates the function of immune cells and stromal cells. Previous studies have shown that PPARG is closely related to the regulation of inflammation. However, the role of PPARG in regulating the pathological processes of RA is poorly understood. MATERIALS AND METHODS: PPARG expression was examined in the synovial tissues and peripheral blood mononuclear cells (PBMCs) from RA patients and the paw of collagen-induced arthritis (CIA) model rats. Molecular biology experiments were designed to examine the effect of PPARG and cannabidiol (CBD) on RAW264.7 cells and CIA rats. RESULTS: The results reveal that PPARG accelerates reactive oxygen species (ROS) clearance by promoting autophagy, thereby inhibiting ROS-mediated macrophage polarization and NLRP3 inflammasome activation. Notably, CBD may be a promising candidate for understanding the mechanism by which PPARG regulates autophagy-mediated inflammation. CONCLUSIONS: Taken together, these findings indicate that PPARG may have a role for distinguishing between RA patients and healthy control, and for distinguishing RA activity; moreover, PPARG could be a novel pharmacological target for alleviating RA through the mediation of autophagy. CBD can act as a PPARG agonist that alleviates the inflammatory progression of RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Autofagia , Inflamação , PPAR gama , Espécies Reativas de Oxigênio , Animais , Feminino , Humanos , Masculino , Camundongos , Ratos , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Artrite Reumatoide/imunologia , Autofagia/efeitos dos fármacos , Canabidiol/farmacologia , Modelos Animais de Doenças , Inflamassomos/metabolismo , Inflamação/metabolismo , Inflamação/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , PPAR gama/metabolismo , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
4.
Opt Lett ; 49(2): 238-241, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38194537

RESUMO

The ongoing development of ratiometric optical thermometry is mainly trapped in thermally coupled levels of rare-earth ions and inefficient ultraviolet excitation. Herein, a new-type multiple sharp line emitting, blue light-excited K2NaInF6:Mn4+, Eu3+ fluoride phosphor has been reported as a ratiometric thermometer. The f-f transition of Eu3+ paves a steady reference to a highly temperature sensitive Mn4+d-d transition and enables high relative sensitivity of 1.65% K-1 at 573 K. An optical fiber thermometry on a household oven with a relative standard deviation of 0.11% surpasses the standard of precision measurement, showing great potential in practical application. This discovery offers a highly sensitive neotype blue light-excitable ratiometric temperature sensor, that is Mn4+-doped fluoride, promoting practical applications of optical thermometry.

5.
Exp Cell Res ; 433(2): 113828, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37875175

RESUMO

Allergic asthma is a chronic inflammatory disease of airways involving complex mechanisms, including MAS-related GPR family member X2 (MRGPRX2) and its orthologue MRGPRB2 on mast cells (MCs). Although miRNAs have been previously shown to related to allergic asthma, the role of miR-212/132 in this process has not been studied. In this study, the predicted pairing of miRNAs and MRGPRX2 (MRGPRB2) mRNAs was carried out by online databases and the function was verify using in vivo and in vitro experiments. Database prediction showed that miR-212/132 interact with MRGPRX2 and MRGPRB2. miR-212/132 mimics alleviated MRGPRB2 mRNA expression as well as pathology changes in lungs and AHR of mice with airway inflammation in vivo. The expression level of MRGPRB2 in the mice lungs after inhaled OVA was also decreased by miR-212/132 mimics. Meanwhile, miR-212/132 inhibited MCs degranulation and cytokines release triggered by C48/80 in vitro. Further, ASAP1 (ARF GTPase-Activating Protein 1) was selected from the junction related pathways using RNAseq and KEGG enrichment. ASAP1 mRNA level was upregulated in airway inflammation and MCs activation and decreased by miR-212/132 mimics. miR-212/132 attenuated OVA-induced airway inflammation by inhibiting MCs activation through MRGPRX2 and ASAP1.


Assuntos
Asma , Mastócitos , MicroRNAs , Animais , Camundongos , Asma/induzido quimicamente , Asma/genética , Asma/metabolismo , Degranulação Celular , Inflamação/induzido quimicamente , Inflamação/metabolismo , Mastócitos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Ovalbumina/efeitos adversos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , RNA Mensageiro/metabolismo , Humanos
6.
Appl Microbiol Biotechnol ; 108(1): 376, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884656

RESUMO

Mushroom poisoning contributes significantly to global foodborne diseases and related fatalities. Amanita mushrooms frequently cause such poisonings; however, identifying these toxic species is challenging due to the unavailability of fresh and intact samples. It is often necessary to analyze residues, vomitus, or stomach extracts to obtain DNA sequences for the identification of species responsible for causing food poisoning. This usually proves challenging to obtain usable DNA sequences that can be analyzed using conventional molecular biology techniques. Therefore, this study aimed to develop a DNA mini-barcoding method for the identification of Amanita species. Following the evaluation and optimization of universal primers for DNA mini-barcoding in Amanita mushrooms, we found that the internal transcribed spacer (ITS) gene sequence primer ITS-a was the most suitable DNA barcode primer for identifying Amanita species. Forty-three Amanita samples were subsequently amplified and sequenced. The sequences obtained were analyzed for intra- and inter-species genetic distances, and a phylogenetic tree was constructed. The findings indicated that the designed primers had strong universality among the Amanita samples and could accurately identify the target gene fragment with a length of 290 bp. Notably, the DNA mini-barcode accurately identified the 43 Amanita samples, demonstrating high consistency with the conventional DNA barcode. Furthermore, it effectively identified DNA from digested samples. In summary, this DNA mini-barcode is a promising tool for detecting accidental ingestion of toxic Amanita mushrooms. It may be used as an optimal barcode for species identification and traceability in events of Amanita-induced mushroom poisoning. KEY POINTS: • Development of a DNA mini-barcoding method for Amanita species identification without fresh samples. • The ITS-a primer set was optimized for robust universality in Amanita samples. • The mini-barcode is suitable for screening toxic mushroom species in mushroom poisoning cases.


Assuntos
Amanita , Código de Barras de DNA Taxonômico , DNA Fúngico , Intoxicação Alimentar por Cogumelos , Filogenia , Intoxicação Alimentar por Cogumelos/diagnóstico , Amanita/genética , DNA Fúngico/genética , Primers do DNA/genética , DNA Espaçador Ribossômico/genética , Análise de Sequência de DNA , Humanos
7.
Fa Yi Xue Za Zhi ; 40(1): 20-29, 2024 Feb 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38500457

RESUMO

OBJECTIVES: To explore the context and hotspot changes of forensic mixed stain research through bibliometric approach. METHODS: The literature of forensic mixed stain included in the core collection of Web of Science database from 2011 to 2022 were collected as the study object, and the annual publication number, countrie (region), institution, journal, keywords, etc. were bibliometrically and visually analyzed using the R-based Bibliometrix 1.1.6 package and VOSviewer 1.6.18 software. RESULTS: A total of 732 articles on forensic mixed stain were included from 2011 to 2022, with the annual number of articles published and the annual citation frequency showing a steady increase year by year. Among the 59 countries (regions) with the most published articles, the United States ranked first with 246 articles, followed by China with 153 articles. The literature came from 104 journals, and the total number of articles published in the top 10 journals was 633. FORENSIC SCI INT GENET ranked first with 307 articles. Visual analysis using VOSviewer software showed that keywords could be divided into four research clusters, namely the genetic marker development group (blue), the mixed stain typing analysis theory group (red), the sequencing analysis group (yellow), and the case sample research group (green). It can be divided into four development stages in terms of different time periods: early development (2011-2013), middle development (2014-2016), rapid development (2017-2020) and latest development (2021-2022). CONCLUSIONS: The number of publications by domestic and foreign scholars in the study of mixed stain in forensic science is showing a relatively stable trend. Machine learning, next generation sequencing and other research have been the hottest topics that have attracted the most attention in recent years, which is expected to further develop the theory of mixed stain typing and sequencing analysis in forensic mixed stain research.


Assuntos
Bibliometria , Corantes , China , Ciências Forenses , Sequenciamento de Nucleotídeos em Larga Escala
8.
Mol Cancer ; 22(1): 42, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859310

RESUMO

N6-methyladenosine (m6A) methylation is the most universal internal modification in eukaryotic mRNA. With elaborate functions executed by m6A writers, erasers, and readers, m6A modulation is involved in myriad physiological and pathological processes. Extensive studies have demonstrated m6A modulation in diverse tumours, with effects on tumorigenesis, metastasis, and resistance. Recent evidence has revealed an emerging role of m6A modulation in tumour immunoregulation, and divergent m6A methylation patterns have been revealed in the tumour microenvironment. To depict the regulatory role of m6A methylation in the tumour immune microenvironment (TIME) and its effect on immune evasion, this review focuses on the TIME, which is characterized by hypoxia, metabolic reprogramming, acidity, and immunosuppression, and outlines the m6A-regulated TIME and immune evasion under divergent stimuli. Furthermore, m6A modulation patterns in anti-tumour immune cells are summarized.


Assuntos
Evasão da Resposta Imune , Microambiente Tumoral , Humanos , Metilação , Adenosina , Carcinogênese
9.
Small ; 19(22): e2300699, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36843312

RESUMO

AgCuSe-based materials have attracted great attentions recently in thermoelectric (TE) field due to their extremely high electron mobility, ultralow lattice thermal conductivity, and abnormal "brittle-ductile" transition at room temperature. However, although the investigation on the crystal structure of AgCuSe low-temperature phase (named as ß-AgCuSe) was started more than half a century before, it is still in controversy yet, which greatly limits the understanding of its intriguing electrical, thermal, and mechanical performance. In this work, via adopting the advanced three-dimensional electron diffraction technique, this study finds that the AgCuSe-based materials crystalize in an incommensurately modulated structure with an orthorhombic Pmmn(0ß1/2)s00 superspace group. The local lattice distortion in the incommensurately modulated structure has weak effects on the conduction band minimum due to the delocalized and isotropic feature of Ag 5s states, leading to high carrier mobility. Likewise, the inhomogeneous, weak, and anisotropic Ag-Se bonds result in the high degree of anharmonicity and ultralow lattice thermal conductivity. Furthermore, alloying S in AgCuSe reinforces the interaction between the adjacent Ag-Se layers, yielding the "brittle-ductile" transition at room temperature. This work well interprets the structure-performance relationship of AgCuSe-based materials and sheds light on the future investigation of this class of promising TE materials.

10.
Small ; 19(52): e2304718, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37621034

RESUMO

Materials with low thermal conductivity have received significant attention across various research fields, including thermal insulation materials, thermal barrier coatings, and thermoelectric materials. Exploring novel materials with intrinsically low thermal conductivity and investigating their phonon transport properties, chemical bonding, and atomic coordination are crucial. In this study, a novel ternary sulfide is successfully discovered, Cu2 ZrS3 , which is achieved by introducing copper ions into both the interlayer and intralayer of ZrS2 . The resulting structure encompasses various coordination forms within each layer, such as [CuS4 ], [ZrS6 ], and [CuS3 ], leading to pronounced phonon anharmonicity induced by the asymmetric bonding of tri-coordinated Cu atoms within the [ZrS6 ] layer. As a result, Cu2 ZrS3 exhibits intrinsically low lattice thermal conductivity (κL ) of about 0.83 W m-1 K-1 at 300 K and 0.35 W m-1 K-1 at 683 K, which are in the exceptionally low level among sulfides. In comparison to the conventional approach of inserting guests between layers, the substitution of atoms within layers provides a novel and effective strategy for designing low κL materials in transition metal dichalcogenides (TMDCs).

11.
Inorg Chem ; 62(20): 7964-7975, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37164943

RESUMO

Development of highly thermally stable broadband near-infrared (NIR) luminescence materials is crucial for advancing the prolonged stable application of smart NIR light sources. In this study, a zero-thermal-quenching and reversible temperature-dependent broadband NIR-emitting Cs2NaAl3F12:Cr3+ phosphor is demonstrated, benefiting from its stable polyhedron-cluster-building rigid structure. The excellent thermal stability of Cs2NaAl3F12:Cr3+ is rooted in its stable [Al6Na4F45] cluster building unit, which provides a rigid structure with a weak electron-phonon coupling effect and a wide band gap with a huge thermal activated barrier. Such characteristics are well revealed by multiple studies on crystal structure, electronic structure, Huang-Rhys factor S, configuration coordinate model, and Debye temperature. The incorporation of Li or K instead of Na weakens the luminescence thermal stability, directly proving the importance of the stable [Al6Na4F45] cluster for stable Cr3+ substitution and rigid structure construction. Furthermore, Cs2NaAl3F12:Cr3+ presents much superior thermal stability compared to traditional rigid garnet-type fluorides Na3X2Li3F12:Cr3+ (X = Al, Ga, In). A high-power NIR LED is presented, utilizing the high quantum efficiency (∼71%) and extremely thermally stable broadband NIR emission around 750 nm of Cs2NaAl3F12:Cr3+. It realizes clear vein and cartilage imaging in the human hand, demonstrating its potential in medical diagnosis applications. This result provides important insights for designing new-type rigid crystal structures using stable polyhedron clusters as basic units, advancing the development of highly thermally stable NIR-emitting phosphors.

12.
Mol Biol Rep ; 50(11): 9273-9282, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37812351

RESUMO

BACKGROUND: As the world's leading fiber crop and a major oil-producing crop, cotton fiber yield and fiber quality are affected by environmental stresses, especially heat, drought and salinity. The LAZ1 (Lazarus 1) family genes are responsive to abscisic acid, drought, and salt treatments. Currently, mining and functional analyses of LAZ1 family genes in cotton have not been reported. METHODS AND RESULTS: In this study, 20 GhLAZ1 genes, designated GhLAZ1-1 - GhLAZ1-20, were identified in the genome of Gossypium hirsutum through the construction of an HMM model, and their molecular properties, chromosomal localization, phylogeny, gene structure, evolutionary selection pressure, promoter cis elements and gene expression under salt stress were analyzed. With the exception of GhLAZ1-17 and GhLAZ1-20, the remaining 18 GhLAZ1 genes were unevenly localized on 13 chromosomes in G. hirsutum; evolutionary analysis showed that these genes could be divided into three subfamilies; and evolutionary selection pressure analysis demonstrated that the GhLAZ1 genes were all under purifying selection. Many elements related to light responses, hormone responses, and abiotic stresses were predicted on the GhLAZ1 family gene promoters, and real-time quantitative PCR results showed that GhLAZ1-2, GhLAZ1-8, and GhLAZ1-18 were upregulated significantly in salt-treated cotton leaves. CONCLUSIONS: Our results suggested that GhLAZ1 genes were involved in the salt tolerance mechanism in G. hirsutum and provided a reference for further exploring the function and molecular mechanism of LAZ1 genes.


Assuntos
Gossypium , Família Multigênica , Gossypium/genética , Estresse Fisiológico/genética , Regiões Promotoras Genéticas/genética , Ácido Abscísico , Regulação da Expressão Gênica de Plantas/genética , Filogenia , Proteínas de Plantas/genética
13.
J Am Chem Soc ; 144(18): 8030-8037, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35446042

RESUMO

The conduction type of semiconductors is vitally important in many fields (e.g., photovoltaics, transistors, and thermoelectrics), but so far, there is no effective and simple indicator to quickly judge or predict the conduction type of various semiconductors. In this work, based on the relationship between the formation energy of charged defect and the Fermi level, we propose a simple and low-cost strategy for high-throughput screening the potential n-type or p-type semiconductors from the material database by using energy positions of band edges as indicators. As a case study, we validate this strategy in searching potential n-type thermoelectric materials from copper (Cu)-containing metal chalcogenides. A new promising thermoelectric material, CuIn5Se8, with potential intrinsic n-type conduction, is successfully screened from 407 Cu-containing metal chalcogenides and validated in the subsequent experiments. Upon doping iodine in CuIn5Se8, a peak thermoelectric figure of merit zT of 0.84 is obtained at 850 K. Beyond thermoelectrics, the strategy proposed in this study also sheds light on the new material development with desired conduction types in photovoltaics, transistors, and other fields.

14.
J Org Chem ; 87(19): 12759-12771, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36170012

RESUMO

Herein, we report dialkoxylation of N-substituted indoles through a hypervalent iodine-mediated umpolung strategy, affording trans-2,3-dimethoxyindolines with up to 95% yield. In addition, C5-selective bromination of 2,3-dialkoxyindoline via NBS-mediated rearomatization was achieved. DFT calculation of the sequence of electrophilic addition and nucleophilic substitution pathway of N-substituted indoles has also been investigated.


Assuntos
Iodo , Indóis , Iodetos
15.
Mol Biol Rep ; 49(7): 6405-6413, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35441355

RESUMO

BACKGROUND: Upland cotton is one of the main cultivated species of cotton, and salt stress is an important factor in its growth and development. Wall-associated receptor kinase galacturonan binding (GUB_WAK_bind) is an extracellular domain of wall-associated kinase (WAK), which can sense the environment and play a role in the response to plant stress. METHODS AND RESULTS: In this study, the GUB_WAK_bind gene in Gossypium hirsutum was identified and analyzed by bioinformatics at the whole genome level, including its physicochemical properties, evolutionary development, gene structure, chromosome positioning, cis-acting elements in the promoter, etc., and the expression of the GUB_WAK_bind genes under salt stress were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). A total of 22 GUB_WAK_bind gene members were identified in Gossypium hirsutum and divided into three subgroups by evolutionary development and motif analysis, most of which contained motif 5, which is similar to the motif pattern of subgroup members. The number of exons in this gene family is between 1 and 4, the number of introns is between 0 and 3, and 22 gene members are distributed on 14 chromosomes of Gossypium hirsutum. Almost all gene members have adverse stress response elements in their promoter region. The expression analysis in response to salt stress showed that the selected six genes were induced by NaCl stress with significant expression differences (P < 0.05). CONCLUSIONS: The results of this study have a certain reference value for understanding the evolution and function of GUB_WAK_bind genes and studying the salt tolerance genes of Gossypium hirsutum.


Assuntos
Genoma de Planta , Gossypium , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Gossypium/genética , Família Multigênica , Filogenia , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
16.
Sensors (Basel) ; 22(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36015752

RESUMO

To study the effect of frequency on the attenuation characteristics of acoustic emission signals in wood, in this paper, two types of hard wood and soft wood were studied separately, and the energy attenuation model of the propagation process of AE sources with different frequencies was established. First, using the piezoelectric inverse effect of the AE sensor, an arbitrary waveform generator was used to generate frequency-tunable pulses in the range of 1 kHz to 150 kHz as the AE source, where the AE source energy could be regulated by the output voltage level. Then, five AE sensors were placed at equal intervals of 100 mm on the surface of the specimen to collect AE signals, and the sampling frequency was set to 500 kHz. Finally, the energy value of AE signal of each sensor was calculated based on the AC principle, and the energy attenuation model was established by exponential fitting. The results showed that both the amplitude and energy of the AE signals of different frequencies showed negative exponential decay with the increase of propagation distance, and, at the same frequency, the change of AE source energy level had no significant effect on its attenuation rate. Compared with hard wood, the energy attenuation of the AE signal of soft wood was more sensitive to the change of frequency, and, at the same frequency, the attenuation rate of soft wood was smaller than that of hard wood.


Assuntos
Acústica , Madeira
17.
Molecules ; 27(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35164219

RESUMO

Firstly, 2,3-butanediol (2,3-BDO) is a chemical platform used in several applications. However, the pathogenic nature of its producers and the expensive feedstocks used limit its scale production. In this study, cane molasses was used for 2,3-BDO production by a nonpathogenic Clostridium ljungdahlii. It was found that cane molasses alone, without the addition of other ingredients, was favorable for use as the culture medium for 2,3-BDO production. Compared with the control (i.e., the modified DSMZ 879 medium), the differential genes are mainly involved in the pathways of carbohydrate metabolism, membrane transport, and amino acid metabolism in the case of the cane molasses alone. However, when cane molasses alone was used, cell growth was significantly inhibited by KCl in cane molasses. Similarly, a high concentration of sugars (i.e., above 35 g/L) can inhibit cell growth and 2,3-BDO production. More seriously, 2,3-BDO production was inhibited by itself. As a result, cane molasses alone with an initial 35 g/L total sugars was suitable for 2,3-BDO production in batch culture. Finally, an integrated fermentation and membrane separation process was developed to maintain high 2,3-BDO productivity of 0.46 g·L-1·h-1. Meanwhile, the varied fouling mechanism indicated that the fermentation properties changed significantly, especially for the cell properties. Therefore, the integrated fermentation and membrane separation process was favorable for 2,3-BDO production by C. ljungdahlii using cane molasses.


Assuntos
Reatores Biológicos , Butileno Glicóis/metabolismo , Clostridium/metabolismo , Fermentação , Membranas/metabolismo , Melaço/análise , Técnicas de Cultura Celular por Lotes , Butileno Glicóis/química , Clostridium/crescimento & desenvolvimento , Membranas/química
18.
Exp Eye Res ; 213: 108810, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34757002

RESUMO

Retinal arterial macroaneurysms are characterized by the acquired fusiform or saccular dilatations of the retinal artery. Angiotensin II (Ang II) is a major signal molecule of the renin-angiotensin system, which exerts a range of pathogenic actions that are relevant to retinal vascular abnormalities. We aimed to study the effect of Ang II on retinal vessels and explore its relationship with retinal aneurysmal disease. C57BL/6J male mice were administered Ang II at 1000 ng/kg/min for 28 days, and the mice given saline served as controls. The mice in the treatment group were treated once daily by gastric gavage of candesartan cilexetil (an antagonist of Ang II type 1 (AT1) receptor) at 100 mg/kg/day. The in vivo imaging of murine retinas was performed using fundus photography, optical coherence tomography, fluorescein angiography, and indocyanine green angiography at 7th, 14th, and 28th days of infusion. At the end of the infusion and treatment, the morphological changes were evaluated by histopathological examination and electron microscopy; the levels of related proteins in murine retinas were examined by antibody array and Western blot analyses. We found that Ang II infusion induced aneurysm formation in mice retina, which presented as either solitary aneurysms or retinal arterial beading. The aneurysm formation was often accompanied with vessel leakage. Moreover, Ang II infusion itself may result in increased vascular permeability and ganglion cell and inner plexiform layer thickening. The blockade of AT1 receptors by systemic administration of candesartan cilexetil alleviated the Ang II-induced retinal vasculopathy. The protein level analysis further showed that Ang II upregulated IL-1ß, PDGFR-ß, and MMP-9 expression, and the expression of IL-1ß could be inhibited by AT1 receptor antagonist. Our study provides evidence that Ang II is a crucial factor in retinal aneurysm formation and vessel leakage. It is probably the combined effect of Ang II on vessel inflammatory response, pericyte function, and extracellular matrix remodeling that predisposes the retinal arterial wall to aneurysm formation and blood-retinal barrier breakdown.


Assuntos
Angiotensina II/fisiologia , Macroaneurisma Arterial Retiniano/metabolismo , Artéria Retiniana/fisiopatologia , Vasoconstritores/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Benzimidazóis/farmacologia , Compostos de Bifenilo/farmacologia , Pressão Sanguínea/fisiologia , Barreira Hematorretiniana , Western Blotting , Corantes/administração & dosagem , Modelos Animais de Doenças , Angiofluoresceinografia , Verde de Indocianina/administração & dosagem , Interleucina-1beta/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Macroaneurisma Arterial Retiniano/diagnóstico , Macroaneurisma Arterial Retiniano/tratamento farmacológico , Tetrazóis/farmacologia , Tomografia de Coerência Óptica
19.
Nucleic Acids Res ; 47(1): 391-405, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30371886

RESUMO

In human cells, telomeres are elongated by the telomerase complex that contains the reverse transcriptase hTERT and RNA template TERC/hTR. Poly(A)-specific ribonuclease (PARN) is known to trim hTR precursors by removing poly(A) tails. However, the precise mechanism of hTR 3' maturation remains largely unknown. Target of Egr1 (TOE1) is an Asp-Glu-Asp-Asp (DEDD) domain containing deadenylase that is mutated in the human disease Pontocerebella Hypoplasia Type 7 (PCH7) and implicated in snRNA and hTR processing. We have previously found TOE1 to localize specifically in Cajal bodies, where telomerase RNP complex assembly takes place. In this study, we showed that TOE1 could interact with hTR and the telomerase complex. TOE1-deficient cells accumulated hTR precursors, including oligoadenylated and 3'-extended forms, which was accompanied by impaired telomerase activity and shortened telomeres. Telomerase activity in TOE1-deficient cells could be rescued by wild-type TOE1 but not the catalytically inactive mutant. Our results suggest that hTR 3' end processing likely involves multiple exonucleases that work in parallel and/or sequentially, where TOE1 may function non-redundantly as a 3'-to-5' exonuclease in conjunction with PARN. Our study highlights a mechanistic link between TOE1 mutation, improper hTR processing and telomere dysfunction in diseases such as PCH7.


Assuntos
Doenças Cerebelares/genética , Proteínas Nucleares/genética , Homeostase do Telômero/genética , Telômero/genética , Doenças Cerebelares/patologia , Exonucleases/genética , Exorribonucleases/genética , Células HeLa , Humanos , Mutação , RNA/genética , Telomerase/genética
20.
BMC Ophthalmol ; 20(1): 105, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32178637

RESUMO

BACKGROUND: To study the morphologic and biochemical changes in the retina and sclera induced by form deprivation high myopia (FDHM) in guinea pigs and explore the possible mechanisms of FDHM formation. METHODS: Forty 3-week-old guinea pigs were randomized into the blank control (Group I, 20 cases) and model groups (20 cases). In the model group, the right eyes of the guinea pigs were sutured for 8 weeks to induce FDHM (Group II) and the left eyes were considered a self-control group (Group III). The refractive errors were measured with retinoscopy. The anterior chamber depth (AC), lens thickness (L), vitreous chamber depth (V) and axial length (AL) were measured using ultrasonometry A. Retinal and scleral morphology and ultrastructural features were observed with light and electron microscopy. The malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in the retina and sclera were detected with a chemical colorimetric assay. RESULTS: After 8 weeks of stitching, the refractive errors of Group II changed from (+ 3.59 ± 0.33) D to (- 7.96 ± 0.55) D, and these values were significantly higher than those of Group I (+ 0.89 ± 0.32) D and Group III (- 0.55 ± 0.49) D (P < 0.05). The vitreous chamber depth (4.12 ± 0.13) mm and axial length (8.93 ± 0.22) mm of Group II were significantly longer than those of Group I [(3.71 ± 0.23) mm and (7.95 ± 0.37) mm, respectively] and Group III [(3.93 ± 0.04) mm and (8.01 ± 0.15) mm, respectively] (P < 0.05). With the prolongation of form deprivation (FD), the retina and scleral tissues showed thinning, the ganglion cell and inner and outer nuclear layers of the retina became decreased, and the arrangement was disordered. In Group II, the SOD activity was significantly lower than that in Group I and Group III; the MDA content was significantly higher than that in Group I and Group III. The differences were statistically significant (P < 0.05). CONCLUSIONS: These findings suggested that in the FDHM guinea pigs model, the refractive errors, the vitreous chamber depth, and axial length increased significantly with prolongation of monocular FD time, and morphological structural changes in the retina and sclera were observed. Oxygen free radicals might participate in the formation of FDHM.


Assuntos
Proteínas do Olho/metabolismo , Miopia Degenerativa/diagnóstico , Retina/patologia , Esclera/patologia , Animais , Modelos Animais de Doenças , Cobaias , Miopia Degenerativa/metabolismo , Retina/metabolismo , Retinoscopia , Esclera/metabolismo
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