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1.
PLoS Genet ; 19(9): e1010937, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37756323

RESUMO

Telomeric repeat-containing RNA (TERRA) is a class of long noncoding RNAs (lncRNAs) that are transcribed from subtelomeric to telomeric region of chromosome ends. TERRA is prone to form R-loop structures at telomeres by invading into telomeric DNA. Excessive telomere R-loops result in telomere instability, so the TERRA level needs to be delicately modulated. However, the molecular mechanisms and factors controlling TERRA level are still largely unknown. In this study, we report that the RNA binding protein RBMX is a novel regulator of TERRA level and telomere integrity. The expression level of TERRA is significantly elevated in RBMX depleted cells, leading to enhanced telomere R-loop formation, replication stress, and telomere instability. We also found that RBMX binds to TERRA and the nuclear exosome targeting protein ZCCHC8 simultaneously, and that TERRA degradation slows down upon RBMX depletion, implying that RBMX promotes TERRA degradation by regulating its transportation to the nuclear exosome, which decays nuclear RNAs. Altogether, these findings uncover a new role of RBMX in TERRA expression regulation and telomere integrity maintenance, and raising RBMX as a potential target of cancer therapy.


Assuntos
Exossomos , RNA Longo não Codificante , Exossomos/genética , Heterocromatina , Proteínas Nucleares , RNA Longo não Codificante/genética , Telômero/genética , Humanos
2.
Proc Natl Acad Sci U S A ; 119(40): e2200835119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161936

RESUMO

Ice cores from alpine glaciers are unique archives of past global and regional climate conditions. However, recovering climate records from these ice cores is often hindered by the lack of a reliable chronology, especially in the age range of 100 to 500 anni (a) for which radiometric dating has not been available so far. We report on radiometric 39Ar dating of an ice core from the Tibetan Plateau and the construction of a chronology covering the past 1,300 a using the obtained 39Ar ages. This is made possible by advances in the analysis of 39Ar using the laser-based detection method atom trap trace analysis, resulting in a twofold increase in the upper age limit of 39Ar dating. By measuring the anthropogenic 85Kr along with 39Ar we quantify and correct modern air contamination, thus removing a major systematic uncertainty of 39Ar dating. Moreover, the 85Kr data for the top part of the ice core provide information on firn processes, including the age difference between the ice and its enclosed gas. This first application of 39Ar and 85Kr to an ice core facilitates further ice cores from nonpolar glaciers to be used for recovering climate records of the Common Era, a period including pronounced anomalies such as the Little Ice Age and the Medieval Warm Period.


Assuntos
Camada de Gelo , Datação Radiométrica , Clima , Mudança Climática , Datação Radiométrica/métodos , Tibet
3.
Small ; 20(6): e2307242, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37771206

RESUMO

Photovoltaic thin film solar cells based on kesterite Cu2 ZnSn(S, Se)4 (CZTSSe) have reached 13.8% sunlight-to-electricity conversion efficiency. However, this efficiency is still far from the Shockley-Queisser radiative limit and is hindered by the significant deficit in open circuit voltage (VOC ). The presence of high-density interface states between the absorber layer and buffer or window layer leads to the recombination of photogenerated carriers, thereby reducing effective carrier collection. To tackle this issue, a new window structure ZnO/AgNW/ZnO/AgNW (ZAZA) comprising layers of ZnO and silver nanowires (AgNWs) is proposed. This structure offers a simple and low-damage processing method, resulting in improved optoelectronic properties and junction quality. The ZAZA-based devices exhibit enhanced VOC due to the higher built-in voltage (Vbi ) and reduced interface recombination compared to the usual indium tin oxide (ITO) based structures. Additionally, improved carrier collection is demonstrated as a result of the shortened collection paths and the more uniform carrier lifetime distribution. These advances enable the fabrication of the first ITO-free CZTSSe solar cells with over 10% efficiency without an anti-reflective coating.

4.
J Med Virol ; 96(8): e29882, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39185672

RESUMO

Establishing reliable noninvasive tools to precisely diagnose clinically significant liver fibrosis (SF, ≥F2) remains an unmet need. We aimed to build a combined radiomics-clinic (CoRC) model for triaging SF and explore the additive value of the CoRC model to transient elastography-based liver stiffness measurement (FibroScan, TE-LSM). This retrospective study recruited 595 patients with biopsy-proven liver fibrosis at two centers between January 2015 and December 2021. At Center 1, the patients before December 2018 were randomly split into training (276) and internal test (118) sets, the remaining were time-independent as a temporal test set (96). Another data set (105) from Center 2 was collected for external testing. Radiomics scores were built with selected features from Deep learning-based (ResUNet) automated whole liver segmentations on MRI (T2FS and delayed enhanced-T1WI). The CoRC model incorporated radiomics scores and relevant clinical variables with logistic regression, comparing routine approaches. Diagnostic performance was evaluated by the area under the receiver operating characteristic curve (AUC). The additive value of the CoRC model to TE-LSM was investigated, considering necroinflammation. The CoRC model achieved AUCs of 0.79 (0.70, 0.86), 0.82 (0.73, 0.89), and 0.81 (0.72-0.91), outperformed FIB-4, APRI (all p < 0.05) in the internal, temporal, and external test sets and maintained the discriminatory power in G0-1 subgroups (AUCs range, 0.85-0.86; all p < 0.05). The AUCs of joint CoRC-LSM model were 0.86 (0.79-0.94), and 0.81 (0.72-0.90) in the internal and temporal sets (p = 0.01). The CoRC model was useful for triaging SF, and may add value to TE-LSM.


Assuntos
Técnicas de Imagem por Elasticidade , Cirrose Hepática , Fígado , Imageamento por Ressonância Magnética , Humanos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Adulto , Técnicas de Imagem por Elasticidade/métodos , Fígado/patologia , Fígado/diagnóstico por imagem , Curva ROC , Aprendizado Profundo , Idoso , Triagem/métodos
5.
Exp Eye Res ; 245: 109956, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38849003

RESUMO

Exposure to particulate matters in air pollution of 2.5 µm or less (PM2.5) was associated with loss of meibomian glands. The aim of this study was to verify that PM2.5 could directly impact meibomian gland epithelial cells and damage their function. To investigate the impact of PM2.5 on meibomian gland, immortalized human meibomian gland epithelial cells were treated with various concentrations of PM2.5in vitro. Meibomian gland cell microstructure, cell viability, expression of proliferating cell nuclear antigen and IL-1ß, and intracellular accumulation of acidic vesicles were measured by transmission electron microscopy, cell counting, Western blot and LysoTracker staining, respectively. To further study the effect of PM2.5in vivo, male C57BL/6J mice were treated with 5 mg/ml PM2.5 or vehicle for 3 months. Corneal fluorescein staining and ocular examinations were done before and after the treatment. Eyelids tissues were processed for morphological studies, immunostaining and Oil Red O staining. Our data suggest that exposure to PM2.5 caused significant meibomian gland dropout, clogged gland orifice and increased corneal fluorescein staining that were consistent with the clinical presentations of meibomian gland dysfunction. Prominent changes in the morphology and ultrastructure of meibomian glands was observed with PM2.5 treatment. PM2.5 promoted ductal keratinization, inhibited cell proliferation, induced cell apoptosis and increased Interleukin-1ß production in meibomian gland epithelial cells. This study may explain the association between PM2.5 exposure and meibomian gland dropout observed in clinic. PM2.5 resuspension instillation could be used to induce a meibomian gland dysfunction animal model.


Assuntos
Sobrevivência Celular , Células Epiteliais , Glândulas Tarsais , Camundongos Endogâmicos C57BL , Material Particulado , Material Particulado/toxicidade , Animais , Glândulas Tarsais/efeitos dos fármacos , Glândulas Tarsais/metabolismo , Glândulas Tarsais/patologia , Camundongos , Masculino , Humanos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Western Blotting , Microscopia Eletrônica de Transmissão , Disfunção da Glândula Tarsal/induzido quimicamente , Disfunção da Glândula Tarsal/metabolismo , Modelos Animais de Doenças , Contagem de Células , Interleucina-1beta/metabolismo , Células Cultivadas , Apoptose/efeitos dos fármacos
6.
Langmuir ; 40(32): 16757-16770, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39079054

RESUMO

We present a machine learning (ML) approach to static contact angle measurement, trained on a large data set (>7.2 million) of half drop contours based on solutions to the Young-Laplace equation where the contact angle is known a priori (removing all sources of error from human input). The data set included the effects of surface roughness, gravity, the size of drop relative to the image, and reflections of the drop on the surface. The presented ML model (valid for contact angles >110°), in combination with a new automated image and contour processing approach, is shown to be more accurate than other methods when benchmarked against an experimental data set, with an estimated error of 1°. The ML model is also 2 orders of magnitude faster at predicting contact angles than Young-Laplace fitting (the current best practice approach). The accuracy and speed of the presented approach provides a viable pathway toward robust and reproducible high-throughput contact angle analysis. This approach, Conan-ML, is open-source and provided for the use and development of new approaches to goniometry.

7.
Liver Int ; 44(2): 330-343, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38014574

RESUMO

Metabolic dysfunction-associated fatty liver disease (MAFLD) has reached epidemic proportions worldwide and is the most frequent cause of chronic liver disease in developed countries. Within the spectrum of liver disease in MAFLD, steatohepatitis is a progressive form of liver disease and hepatocyte ballooning (HB) is a cardinal pathological feature of steatohepatitis. The accurate and reproducible diagnosis of HB is therefore critical for the early detection and treatment of steatohepatitis. Currently, a diagnosis of HB relies on pathological examination by expert pathologists, which may be a time-consuming and subjective process. Hence, there has been interest in developing automated methods for diagnosing HB. This narrative review briefly discusses the development of artificial intelligence (AI) technology for diagnosing fatty liver disease pathology over the last 30 years and provides an overview of the current research status of AI algorithms for the identification of HB, including published articles on traditional machine learning algorithms and deep learning algorithms. This narrative review also provides a summary of object detection algorithms, including the principles, historical developments, and applications in the medical image analysis. The potential benefits of object detection algorithms for HB diagnosis (specifically those combined with a transformer architecture) are discussed, along with the future directions of object detection algorithms in HB diagnosis and the potential applications of generative AI on transformer architecture in this field. In conclusion, object detection algorithms have huge potential for the identification of HB and could make the diagnosis of MAFLD more accurate and efficient in the near future.


Assuntos
Inteligência Artificial , Hepatopatia Gordurosa não Alcoólica , Humanos , Algoritmos , Tecnologia , Hepatócitos
8.
Eye Contact Lens ; 50(2): 102-105, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37988104

RESUMO

OBJECTIVE: To determine whether fibroblast growth factor receptor (FGFR)-targeting drug could impact human meibomian gland. METHODS: We followed up with three patients who were using pemigatinib for 4 to 10 weeks. The patients were evaluated for their ocular surface disease index, best-corrected visual acuity, Schirmer test, cornea staining, meibum expressibility score, tear meniscus height, noninvasive tear film breakup time, and meibomian gland area. The distribution of the FGFR family, FGF7, and FGF10 were evaluated by immunofluorescence staining and Western blot in fresh tarsal tissues from deidentified patients who underwent lid plastic surgeries. RESULTS: All patients developed apparent meibomian gland atrophy, shortening and narrowing of ducts, and significantly increased meibum expressibility and decreased noninvasive tear film breakup time within 5 to 8 weeks. Laboratory evaluations confirmed that human meibomian gland expresses abundant fibroblast growth factor receptors. CONCLUSIONS: These findings indicate that meibomian gland is a target tissue of FGFR inhibitors, and patients who use these drugs may develop meibomian gland dysfunction.


Assuntos
Síndromes do Olho Seco , Doenças Palpebrais , Disfunção da Glândula Tarsal , Humanos , Glândulas Tarsais/metabolismo , Disfunção da Glândula Tarsal/metabolismo , Lágrimas/metabolismo , Síndromes do Olho Seco/metabolismo
9.
Chem Biodivers ; 21(8): e202400937, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38682724

RESUMO

Three new indole alkaloids, named talatensindoids A-C (1-3), together with two known biogenetically related indole alkaloids tryptamine (4) and L-tryptophan (5) were isolated from the Talaromyces assiutensis JTY2 based on the guidance of OSMAC approach. The structures of these indole alkaloids were determined by comprehensive spectroscopic analyses. The absolute configuration of 3 was confirmed by X-ray crystallographic analysis. Compound 1 represent the rare example of a chlorine-substituted indole alkaloid from natural products. The inhibitory activity of compounds 1-5 against two phytopathogenic fungi and three phytopathogenic bacteria was evaluated. Compound 1 exhibited broad spectrum antibacterial activities.


Assuntos
Alcaloides Indólicos , Testes de Sensibilidade Microbiana , Talaromyces , Talaromyces/química , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/isolamento & purificação , Cristalografia por Raios X , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bactérias/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Conformação Molecular , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Fungos/efeitos dos fármacos , Fungos/química
10.
Chem Biodivers ; 21(4): e202400188, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38372184

RESUMO

Two rare 5/5/5/6 four-ring system iridoids, allamancins A and B (1 and 2) together with one known biogenetically related iridoid derivative, 3-O-methyallamancin (3) were isolated from the flowers of Plumeria alba L. The structures of these iridoid derivatives were determined by comprehensive spectroscopic analyses. The absolute configuration of 1 was confirmed by X-ray crystallographic analysis. The inhibitory activities of compounds 1-3 against nitric oxide (NO) production induced and three cancer cell lines were evaluated in vitro. Compounds 1 and 3 showed inhibitory activities on NO production with IC50 values of 18.3±0.12 and 22.1±0.14 µM, respectively. Compounds 1-3 showed moderate inhibitory activities against cancer cell lines of A549, Hela and MCF-7.


Assuntos
Apocynaceae , Iridoides , Humanos , Iridoides/farmacologia , Iridoides/química , Células HeLa , Apocynaceae/química , Óxido Nítrico/metabolismo , Cristalografia por Raios X , Estrutura Molecular
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