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1.
Cell ; 185(2): 266-282.e15, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-35026153

RESUMEN

HIV-1-infected cells that persist despite antiretroviral therapy (ART) are frequently considered "transcriptionally silent," but active viral gene expression may occur in some cells, challenging the concept of viral latency. Applying an assay for profiling the transcriptional activity and the chromosomal locations of individual proviruses, we describe a global genomic and epigenetic map of transcriptionally active and silent proviral species and evaluate their longitudinal evolution in persons receiving suppressive ART. Using genome-wide epigenetic reference data, we show that proviral transcriptional activity is associated with activating epigenetic chromatin features in linear proximity of integration sites and in their inter- and intrachromosomal contact regions. Transcriptionally active proviruses were actively selected against during prolonged ART; however, this pattern was violated by large clones of virally infected cells that may outcompete negative selection forces through elevated intrinsic proliferative activity. Our results suggest that transcriptionally active proviruses are dynamically evolving under selection pressure by host factors.


Asunto(s)
VIH-1/genética , Provirus/genética , Transcripción Genética , Anciano , Secuencia de Bases , Evolución Biológica , Cromatina/metabolismo , Células Clonales , ADN Viral/genética , Epigénesis Genética/efectos de los fármacos , Femenino , Humanos , Ionomicina/farmacología , Masculino , Persona de Mediana Edad , Filogenia , Provirus/efectos de los fármacos , ARN Viral/genética , Acetato de Tetradecanoilforbol/farmacología , Transcripción Genética/efectos de los fármacos , Integración Viral/genética , Latencia del Virus/efectos de los fármacos , Latencia del Virus/genética
2.
Cell ; 183(1): 143-157.e13, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32877699

RESUMEN

Humoral responses in coronavirus disease 2019 (COVID-19) are often of limited durability, as seen with other human coronavirus epidemics. To address the underlying etiology, we examined post mortem thoracic lymph nodes and spleens in acute SARS-CoV-2 infection and observed the absence of germinal centers and a striking reduction in Bcl-6+ germinal center B cells but preservation of AID+ B cells. Absence of germinal centers correlated with an early specific block in Bcl-6+ TFH cell differentiation together with an increase in T-bet+ TH1 cells and aberrant extra-follicular TNF-α accumulation. Parallel peripheral blood studies revealed loss of transitional and follicular B cells in severe disease and accumulation of SARS-CoV-2-specific "disease-related" B cell populations. These data identify defective Bcl-6+ TFH cell generation and dysregulated humoral immune induction early in COVID-19 disease, providing a mechanistic explanation for the limited durability of antibody responses in coronavirus infections, and suggest that achieving herd immunity through natural infection may be difficult.


Asunto(s)
Infecciones por Coronavirus/inmunología , Centro Germinal/inmunología , Neumonía Viral/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Anciano , Anciano de 80 o más Años , Linfocitos B/inmunología , COVID-19 , Femenino , Centro Germinal/patología , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Proteínas Proto-Oncogénicas c-bcl-6/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Bazo/inmunología , Bazo/patología , Factor de Necrosis Tumoral alfa/metabolismo
3.
Plant Cell ; 36(5): 1736-1754, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38315889

RESUMEN

Roses are among the most popular ornamental plants cultivated worldwide for their great economic, symbolic, and cultural importance. Nevertheless, rapid petal senescence markedly reduces rose (Rosa hybrida) flower quality and value. Petal senescence is a developmental process tightly regulated by various phytohormones. Ethylene accelerates petal senescence, while gibberellic acid (GA) delays this process. However, the molecular mechanisms underlying the crosstalk between these phytohormones in the regulation of petal senescence remain largely unclear. Here, we identified SENESCENCE-ASSOCIATED F-BOX (RhSAF), an ethylene-induced F-box protein gene encoding a recognition subunit of the SCF-type E3 ligase. We demonstrated that RhSAF promotes degradation of the GA receptor GIBBERELLIN INSENSITIVE DWARF1 (RhGID1) to accelerate petal senescence. Silencing RhSAF expression delays petal senescence, while suppressing RhGID1 expression accelerates petal senescence. RhSAF physically interacts with RhGID1s and targets them for ubiquitin/26S proteasome-mediated degradation. Accordingly, ethylene-induced RhGID1C degradation and RhDELLA3 accumulation are compromised in RhSAF-RNAi lines. Our results demonstrate that ethylene antagonizes GA activity through RhGID1 degradation mediated by the E3 ligase RhSAF. These findings enhance our understanding of the phytohormone crosstalk regulating petal senescence and provide insights for improving flower longevity.


Asunto(s)
Etilenos , Proteínas F-Box , Flores , Regulación de la Expresión Génica de las Plantas , Giberelinas , Proteínas de Plantas , Rosa , Etilenos/metabolismo , Etilenos/farmacología , Giberelinas/metabolismo , Giberelinas/farmacología , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Rosa/genética , Rosa/efectos de los fármacos , Rosa/metabolismo , Flores/genética , Flores/efectos de los fármacos , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Senescencia de la Planta/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/genética
4.
Nature ; 585(7824): 261-267, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32848246

RESUMEN

Sustained, drug-free control of HIV-1 replication is naturally achieved in less than 0.5% of infected individuals (here termed 'elite controllers'), despite the presence of a replication-competent viral reservoir1. Inducing such an ability to spontaneously maintain undetectable plasma viraemia is a major objective of HIV-1 cure research, but the characteristics of proviral reservoirs in elite controllers remain to be determined. Here, using next-generation sequencing of near-full-length single HIV-1 genomes and corresponding chromosomal integration sites, we show that the proviral reservoirs of elite controllers frequently consist of oligoclonal to near-monoclonal clusters of intact proviral sequences. In contrast to individuals treated with long-term antiretroviral therapy, intact proviral sequences from elite controllers were integrated at highly distinct sites in the human genome and were preferentially located in centromeric satellite DNA or in Krüppel-associated box domain-containing zinc finger genes on chromosome 19, both of which are associated with heterochromatin features. Moreover, the integration sites of intact proviral sequences from elite controllers showed an increased distance to transcriptional start sites and accessible chromatin of the host genome and were enriched in repressive chromatin marks. These data suggest that a distinct configuration of the proviral reservoir represents a structural correlate of natural viral control, and that the quality, rather than the quantity, of viral reservoirs can be an important distinguishing feature for a functional cure of HIV-1 infection. Moreover, in one elite controller, we were unable to detect intact proviral sequences despite analysing more than 1.5 billion peripheral blood mononuclear cells, which raises the possibility that a sterilizing cure of HIV-1 infection, which has previously been observed only following allogeneic haematopoietic stem cell transplantation2,3, may be feasible in rare instances.


Asunto(s)
Silenciador del Gen , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Heterocromatina/genética , Provirus/genética , Integración Viral/genética , Latencia del Virus/genética , Adulto , Anciano , Centrómero/genética , Cromosomas Humanos Par 19/genética , ADN Satélite/genética , Femenino , Genoma Viral/genética , Infecciones por VIH/sangre , VIH-1/aislamiento & purificación , Heterocromatina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Provirus/aislamiento & purificación , Proteínas Represoras/genética , Sitio de Iniciación de la Transcripción
5.
Proc Natl Acad Sci U S A ; 120(11): e2218960120, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36877848

RESUMEN

HIV post-treatment controllers (PTCs) are rare individuals who maintain low levels of viremia after stopping antiretroviral therapy (ART). Understanding the mechanisms of HIV post-treatment control will inform development of strategies aiming at achieving HIV functional cure. In this study, we evaluated 22 PTCs from 8 AIDS Clinical Trials Group (ACTG) analytical treatment interruption (ATI) studies who maintained viral loads ≤400 copies/mL for ≥24 wk. There were no significant differences in demographics or frequency of protective and susceptible human leukocyte antigen (HLA) alleles between PTCs and post-treatment noncontrollers (NCs, n = 37). Unlike NCs, PTCs demonstrated a stable HIV reservoir measured by cell-associated RNA (CA-RNA) and intact proviral DNA assay (IPDA) during analytical treatment interruption (ATI). Immunologically, PTCs demonstrated significantly lower CD4+ and CD8+ T cell activation, lower CD4+ T cell exhaustion, and more robust Gag-specific CD4+ T cell responses and natural killer (NK) cell responses. Sparse partial least squares discriminant analysis (sPLS-DA) identified a set of features enriched in PTCs, including a higher CD4+ T cell% and CD4+/CD8+ ratio, more functional NK cells, and a lower CD4+ T cell exhaustion level. These results provide insights into the key viral reservoir features and immunological profiles for HIV PTCs and have implications for future studies evaluating interventions to achieve an HIV functional cure.


Asunto(s)
Linfocitos T CD8-positivos , Infecciones por VIH , Humanos , Células Asesinas Naturales , Activación de Linfocitos , ARN , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Viremia
6.
Plant Physiol ; 194(4): 2338-2353, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38084893

RESUMEN

Maintaining proper flower size is vital for plant reproduction and adaption to the environment. Petal size is determined by spatiotemporally regulated cell proliferation and expansion. However, the mechanisms underlying the orchestration of cell proliferation and expansion during petal growth remains elusive. Here, we determined that the transition from cell proliferation to expansion involves a series of distinct and overlapping processes during rose (Rosa hybrida) petal growth. Changes in cytokinin content were associated with the transition from cell proliferation to expansion during petal growth. RNA sequencing identified the AP2/ERF transcription factor gene RELATED TO AP2 4-LIKE (RhRAP2.4L), whose expression pattern positively associated with cytokinin levels during rose petal development. Silencing RhRAP2.4L promoted the transition from cell proliferation to expansion and decreased petal size. RhRAP2.4L regulates cell proliferation by directly repressing the expression of KIP RELATED PROTEIN 2 (RhKRP2), encoding a cell cycle inhibitor. In addition, we also identified BIG PETALub (RhBPEub) as another direct target gene of RhRAP2.4L. Silencing RhBPEub decreased cell size, leading to reduced petal size. Furthermore, the cytokinin signaling protein ARABIDOPSIS RESPONSE REGULATOR 14 (RhARR14) activated RhRAP2.4L expression to inhibit the transition from cell proliferation to expansion, thereby regulating petal size. Our results demonstrate that RhRAP2.4L performs dual functions in orchestrating cell proliferation and expansion during petal growth.


Asunto(s)
Arabidopsis , Rosa , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Regulación del Desarrollo de la Expresión Génica , Citocininas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proliferación Celular/genética , Flores
7.
J Am Chem Soc ; 146(32): 22266-22275, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38996381

RESUMEN

Single-atom catalysts (SACs) with unitary active sites hold great promise for realizing high selectivity toward a single product in the CO2 electroreduction reaction (CO2RR). However, achieving high Faradaic efficiency (FE) of multielectron products like methane on SACs is still challenging. Herein, we report a pressure-regulating strategy that achieves 83.5 ± 4% FE for the CO2-to-CH4 conversion on the asymmetric Cu-N2 sites, representing one of the best CO2-to-CH4 performances. Elevated CO2 pressure was demonstrated as an efficient way to inhibit the hydrogen evolution reaction via promoting the competing adsorption of reactant CO2, regardless of the nature of the active sites. Meanwhile, the asymmetric Cu-N2 structure could endow the Cu sites with stronger electronic coupling with *CO, thus suppressing the desorption of *CO and facilitating the following hydrogenation of *CO to *CHO. This work provides a synergetic strategy of the pressure-induced reaction environment regulating and the electronic structure modulating for selective CO2RR toward targeted products.

8.
Anal Chem ; 96(18): 7101-7110, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38663376

RESUMEN

While DNA amplifier-built nanobiosensors featuring a DNA polymerase-free catalytic hairpin assembly (CHA) reaction have shown promise in fluorescence imaging assays within live biosystems, challenges persist due to unsatisfactory precision stemming from premature activation, insufficient sensitivity arising from low reaction kinetics, and poor biostability caused by endonuclease degradation. In this research, we aim to tackle these issues. One aspect involves inserting an analyte-binding unit with a photoinduced cleavage bond to enable a light-powered notion. By utilizing 808 nm near-infrared (NIR) light-excited upconversion luminescence as the ultraviolet source, we achieve entirely a controllable sensing event during the biodelivery phase. Another aspect refers to confining the CHA reaction within the finite space of a DNA self-assembled nanocage. Besides the accelerated kinetics (up to 10-fold enhancement) resulting from the nucleic acid restriction behavior, the DNA nanocage further provides a 3D rigid skeleton to reinforce enzymatic resistance. After selecting a short noncoding microRNA (miRNA-21) as the modeled low-abundance sensing analyte, we have verified that the innovative NIR light-powered and DNA nanocage-confined CHA nanobiosensor possesses remarkably high sensitivity and specificity. More importantly, our sensing system demonstrates a robust imaging capability for this cancer-related universal biomarker in live cells and tumor-bearing mouse bodies, showcasing its potential applications in disease analysis.


Asunto(s)
Técnicas Biosensibles , ADN , Rayos Infrarrojos , MicroARNs , MicroARNs/análisis , Humanos , Técnicas Biosensibles/métodos , Animales , ADN/química , Ratones , Imagen Óptica , Nanoestructuras/química
9.
Anal Chem ; 96(5): 2142-2151, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38258616

RESUMEN

While three-dimensional (3D) DNA walking amplifiers hold considerable promise in the construction of advanced DNA-based fluorescent biosensors for bioimaging, they encounter certain difficulties such as inadequate sensitivity, premature activation, the need for exogenous propelling forces, and low reaction rates. In this contribution, a variety of profitable solutions have been explored. First, a catalytic hairpin assembly (CHA)-achieved nonenzymatic isothermal nucleic acid amplification is integrated to enhance sensitivity. Subsequently, one DNA component is simply functionalized with a photocleavage-bond to conduct a photoresponsive manner, whereby the target recognition occurs only when the biosensor is exposed to an external ultraviolet light source, overcoming premature activation during biodelivery. Furthermore, a special self-propelling walking mechanism is implemented by reducing biothiols to MnO2 nanosheets, thereby propelling forces that are self-supplied to a Mn2+-reliant DNAzyme. By carrying the biosensing system with a DNA molecular framework to induce a unique concentration localization effect, the nucleic acid contact reaction rate is notably elevated by 6 times. Following these, an ultrasensitive in vitro detection performance with a limit of detection down to 2.89 fM is verified for a cancer-correlated microRNA biomarker (miRNA-21). Of particular importance, our multiple concepts combined 3D DNA walking amplifier that enables highly efficient fluorescence bioimaging in live cells and even bodies, exhibiting a favorable application prospect in disease analysis.


Asunto(s)
Técnicas Biosensibles , ADN Catalítico , MicroARNs , ADN Catalítico/química , Compuestos de Manganeso , Óxidos , ADN/química , MicroARNs/análisis , Técnicas Biosensibles/métodos , Límite de Detección
10.
IUBMB Life ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39139071

RESUMEN

Senescent cells are typically characterized by a stable proliferation arrested in dividing cells accompanied with a senescence-associated secretory phenotype (SASP). Skin cellular senescence is the primary cause of skin aging, whereas the lack of identified skin senescence markers limits our understanding of the mechanisms involved in skin aging. Recent studies have revealed that intracellular calcium signaling has emerged as a key player in regulating cellular senescence and aging. However, the implication and roles of calcium signaling in skin keratinocyte senescence remain only partially understood. In this study, we developed a model for skin keratinocyte senescence using ionizing radiation (I/R) stimulation and found that the calcium-associated gene transglutaminase 2 (TGM2) was significantly induced compared with normal control. Interestingly, inhibition of TGM2 was found to delay skin keratinocyte senescence by suppressing I/R-promoted intracellular calcium signaling, accumulation of reactive oxygen species (ROS), DNA damage, as well as NF-κB-mediated SASP secretion. Taken together, our findings demonstrate that inhibition of TGM2 contributes to bypassing I/R-induced skin keratinocyte senescence and sheds light on novel strategies against skin stresses caused by I/R.

11.
Plant Cell Environ ; 47(2): 387-407, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38058262

RESUMEN

The escalating impact of climate change and ultraviolet (UV) radiation is subjecting plants to unique combinations of UV-B and drought stress. These combined stressors could have additive, synergistic, or antagonistic effects, but the precise nature of these impacts remains uncertain, hampering our ability to predict plant adaptations approach towards stressors. Our analysis of various studies shows that UV-B or drought conditions detrimentally influence plant growth and health metrics by the enhanced generation of reactive oxygen species causing damage to lipids, proteins, carbohydrates and DNA. Further reducing biomass accumulation, plant height, photosynthetic efficiency, leaf area, and water transpiration, while enhancing stress-related symptoms. In response to UV-B radiation and drought stress, plants exhibit a notable up-regulation of specific acclimation-associated metabolites, including proline, flavonoids, anthocyanins, unsaturated fatty acids, and antioxidants. These metabolites play a pivotal role in conferring protection against environmental stresses. Their biosynthesis and functional roles are potentially modulated by signalling molecules such as hydrogen peroxide, abscisic acid, jasmonic acid, salicylic acid, and ethylene, all of which have associated genetic markers that further elucidate their involvement in stress response pathways. In comparison to single stress, the combination of UV-B and drought induces the plant defence responses and growth retardation which are less-than-additive. This sub-additive response, consistent across different study environments, suggests the possibility of a cross-resistance mechanism. Our outlines imply that the adverse effects of increased drought and UV-B could potentially be mitigated by cross-talk between UV-B and drought regimes utilizing a multidimensional approach. This crucial insight could contribute significantly to refining our understanding of stress tolerance in the face of ongoing global climate change.


Asunto(s)
Antocianinas , Resiliencia Psicológica , Sequías , Plantas/efectos de la radiación , Estrés Fisiológico/genética
12.
BMC Cancer ; 24(1): 416, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575885

RESUMEN

BACKGROUND: Through research on the gut microbiota (GM), increasing evidence has indicated that the GM is associated with esophageal cancer (ESCA). However, the specific cause-and-effect relationship remains unclear. In this study, Mendelian randomization (MR) analysis was applied to investigate the causal relationship between the GM and ESCA, including its subtypes. METHODS: We collected information on 211 GMs and acquired data on ESCA and its subtypes through genome-wide association studies (GWASs). The causal relationship was primarily assessed using the inverse variance weighted (IVW) method. Additionally, we applied the weighted median estimator (WME) method, MR-Egger method, weighted mode, and simple mode to provide further assistance. Subsequent to these analyses, sensitivity analysis was conducted using the MR-Egger intercept test, MR-PRESSO global test, and leave-one-out method. RESULT: Following our assessment using five methods and sensitivity analysis, we identified seven GMs with potential causal relationships with ESCA and its subtypes. At the genus level, Veillonella and Coprobacter were positively correlated with ESCA, whereas Prevotella9, Eubacterium oxidoreducens group, and Turicibacter were negatively correlated with ESCA. In the case of esophageal adenocarcinoma (EAC), Flavonifractor exhibited a positive correlation, while Actinomyces exhibited a negative correlation. CONCLUSION: Our study revealed the potential causal relationship between GM and ESCA and its subtypes, offering novel insights for the advancement of ESCA diagnosis and treatment.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Neoplasias Esofágicas/genética
13.
Langmuir ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014533

RESUMEN

By combining molecular simulations and experimental measurements, the effect of the Nafion content on the performance of proton-exchange membrane fuel cells (PEMFCs) is explained from the perspective of the triple-phase boundary (TPB). The evaporation process of Nafion solvent is simulated on a triple-phase model to mimic the formation of the TPB, and the influence of the Nafion content on the TPB structure is investigated. When the Nafion content is 1.415 mg/m2, the coverages of Nafion on both Pt particles and the carbon carrier are saturated at 42.1% and 32.7%, respectively. With the increase of Nafion content, the amount of water molecules around Pt particles is increased, and the surrounding O2 content is decreased. The experimental PEMFC performance has confirmed such simulation results, which demonstrates a trend of enhancing first and then weakening with the increase of Nafion content and reaches a maximum with the Nafion content of 2.96 mg/m2. Therefore, the correlation between the structure of the TPB and the cell's efficiency has been established at a molecular level, enabling enhancements in the design of the TPB morphology and an increase in PEMFC efficiency.

14.
Environ Sci Technol ; 58(1): 960-969, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38150269

RESUMEN

SO2 reduction with CH4 to produce elemental sulfur (S8) or other sulfides is typically challenging due to high energy barriers and catalyst poisoning by SO2. Herein, we report that a comproportionation reaction (CR) induced by H2S recirculating significantly accelerates the reactions, altering reaction pathways and enabling flexible adjustment of the products from S8 to sulfides. Results show that SO2 can be fully reduced to H2S at a lower temperature of 650 °C, compared to the 800 °C required for the direct reduction (DR), effectively eliminating catalyst poisoning. The kinetic rate constant is significantly improved, with CR at 650 °C exhibiting about 3-fold higher value than DR at 750 °C. Additionally, the apparent activation energy decreases from 128 to 37 kJ/mol with H2S, altering the reaction route. This CR resolves the challenges related to robust sulfur-oxygen bond activation and enhances CH4 dissociation. During the process, the well-dispersed lamellar MoS2 crystallites with Co promoters (CoMoS) act as active species. H2S facilitates the comproportionation reaction, reducing SO2 to a nascent sulfur (Sx*). Subsequently, CH4 efficiently activates CoMoS in the absence of SO2, forming H2S. This shifts the mechanism from Mars-van Krevelen (MvK) in DR to sequential Langmuir-Hinshelwood (L-H) and MvK in CR. Additionally, it mitigates sulfation poisoning through this rapid activation reaction pathway. This unique comproportionation reaction provides a novel strategy for efficient sulfur resource utilization.


Asunto(s)
Metano , Dióxido de Azufre , Metano/química , Sulfuros/química , Temperatura , Azufre/química , Oxidación-Reducción
15.
Nucleic Acids Res ; 50(8): 4769-4783, 2022 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-35446403

RESUMEN

It is important to control CRISPR/Cas9 when sufficient editing is obtained. In the current study, rational engineering of guide RNAs (gRNAs) is performed to develop small-molecule-responsive CRISPR/Cas9. For our purpose, the sequence of gRNAs are modified to introduce ligand binding sites based on the rational design of ligand-RNA pairs. Using short target sequences, we demonstrate that the engineered RNA provides an excellent scaffold for binding small molecule ligands. Although the 'stem-loop 1' variants of gRNA induced variable cleavage activity for different target sequences, all 'stem-loop 3' variants are well tolerated for CRISPR/Cas9. We further demonstrate that this specific ligand-RNA interaction can be utilized for functional control of CRISPR/Cas9 in vitro and in human cells. Moreover, chemogenetic control of gene editing in human cells transfected with all-in-one plasmids encoding Cas9 and designer gRNAs is demonstrated. The strategy may become a general approach for generating switchable RNA or DNA for controlling other biological processes.


Asunto(s)
Edición Génica , ARN Guía de Kinetoplastida , Humanos , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo , Sistemas CRISPR-Cas/genética , Ligandos , Plásmidos
16.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34353903

RESUMEN

Vertebrate mammals express a protein called Ki-67 which is most widely known as a clinically useful marker of highly proliferative cells. Previous studies of human cells indicated that acute depletion of Ki-67 can elicit a delay at the G1/S boundary of the cell cycle, dependent on induction of the checkpoint protein p21. Consistent with those observations, we show here that acute Ki-67 depletion causes hallmarks of DNA damage, and the damage occurs even in the absence of checkpoint signaling. This damage is not observed in cells traversing S phase but is instead robustly detected in mitotic cells. The C-terminal chromatin-binding domain of Ki-67 is necessary and sufficient to protect cells from this damage. We also observe synergistic effects when Ki-67 and p53 are simultaneously depleted, resulting in increased levels of chromosome bridges at anaphase, followed by the appearance of micronuclei. Therefore, these studies identify the C terminus of Ki-67 as an important module for genome stability.


Asunto(s)
Cromatina/metabolismo , Cromosomas Humanos , Antígeno Ki-67/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Anafase , Sitios de Unión , Línea Celular , Daño del ADN , Inestabilidad Genómica , Humanos , Antígeno Ki-67/genética , Mitosis , Dominios Proteicos , Proteína p53 Supresora de Tumor/genética , Proteína 1 de Unión al Supresor Tumoral P53/genética , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo
17.
Eye Contact Lens ; 50(1): 41-47, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37934166

RESUMEN

OBJECTIVES: To develop and validate a deep learning-based model for predicting 12-month axial length (AL) elongation using baseline factors and early corneal topographic changes in children treated with orthokeratology (Ortho-K) and to investigate the association between these factors and myopia control impact. METHODS: A total of 115 patients with Ortho-K were enrolled. Influential baseline factors that have a statistically significant correlation with 12-month AL from medical records were selected using Pearson correlation coefficients. Simultaneously, the height, area, and volume of the defocus region were directly calculated from the corneal topography. Then, the prediction model was developed by combining multiple linear regression and deep neural network and evaluated in an independent group (83 patients for developing the algorithm and 32 patients for evaluation). RESULTS: Age ( r= -0.30, P <0.001), spherical equivalent refractive (SE; r =0.20, P =0.032), and sex ( r =0.19, P =0.032) were significantly correlated with the AL elongation while pupil diameter, flat k, steep k, horizontal corneal diameter (white to white), anterior chamber depth, and cell density were not ( P >0.1). The prediction model was developed using age, SE, and corneal topographic variation, and the validation of the model demonstrated its effectiveness in predicting AL elongation. CONCLUSIONS: The AL elongation was accurately predicted by the deep learning model, which effectively incorporated both baseline factors and corneal topographic variation.


Asunto(s)
Aprendizaje Profundo , Miopía , Procedimientos de Ortoqueratología , Niño , Humanos , Longitud Axial del Ojo , Miopía/terapia , Topografía de la Córnea , Refracción Ocular , Estudios Retrospectivos
18.
Eur Arch Otorhinolaryngol ; 281(6): 2893-2903, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38206390

RESUMEN

INTRODUCTION: Currently, age-related hearing loss has become prevalent, awareness and screening rates remain dismally low. Duing to several barriers, as time, personnel training and equipment costs, available hearing screening tools do not adequately meet the need for large-scale hearing detection in community-dwelling older adults. Therefore, an accurate, convenient, and inexpensive hearing screening tool is needed to detect hearing loss, intervene early and reduce the negative consequences and burden of untreated hearing loss on individuals, families and society. OBJECTIVES: The study harnessed "medical big data" and "intelligent medical management" to develop a multi-dimensional screening tool of age-related hearing loss based on WeChat platform. METHODS: The assessment of risk factors was carried out by cross-sectional survey, logistic regression model and receiver operating characteristic (ROC) curve analysis. Combining risk factor assessment, Hearing handicap inventory for the elderly screening version and analog audiometry, the screening software was been developed by JavaScript language and been evaluated and verified. RESULTS: A total of 401 older adults were included in the cross-sectional study. Logistic regression model (univariate, multivariate) and reference to literature mention rate of risk factors, 18 variables (male, overweight/obesity, living alone, widowed/divorced, history of noise, family history of deafness, non-light diet, no exercising habit, smoking, drinking, headset wearer habit, hypertension, diabetes, hyperlipidemia, cardiovascular and cerebrovascular diseases, hyperuricemia, hypothyroidism, history of ototoxic drug use) were defined as risk factors. The area under the ROC curve (AUC) of the cumulative score of risk factors for early prediction of age-related hearing loss was 0.777 [95% CI (0.721, 0.833)]. The cumulative score threshold of risk factors was defined as 4, to classify the older adults into low-risk (< 4) and high-risk (≥ 4) hearing loss groups. The sensitivity, specificity, positive predictive value, and negative predictive value of the screen tool were 100%, 65.5%, 71.8%, and 100.0%, respectively. The Kappa index was 0.6. CONCLUSIONS: The screening software enabled the closed loop management of real-time data transmission, early warning, management, whole process supervision of the hearing loss and improve self-health belief in it. The software has huge prospects for application as a screening approach for age-related hearing loss.


Asunto(s)
Tamizaje Masivo , Humanos , Masculino , Femenino , Anciano , Estudios Transversales , Tamizaje Masivo/métodos , Factores de Riesgo , Persona de Mediana Edad , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/epidemiología , Curva ROC , Anciano de 80 o más Años , Presbiacusia/diagnóstico , Presbiacusia/epidemiología , Medición de Riesgo/métodos , Modelos Logísticos , Vida Independiente
19.
J Craniofac Surg ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109861

RESUMEN

BACKGROUND: The prevalence of skin redundancy and lack of creases in the Asian upper eyelids makes blepharoplasty popular. Although many incision designs have been developed to improve upper eyelid laxity, there is a lack of a universal method to match various upper eyelid conditions. We present a systematic preoperative evaluation and design approach that incorporates eye esthetics to determine the shape and amount of skin to be removed to create attractive eyes. METHODS: A retrospective review of 352 patients who underwent incisional blepharoplasty from May 2020 to May 2022 was performed. The excised area was determined preoperatively according to the degree of upper eyelid skin laxity, and the best of the three precise designs is chosen. RESULTS: All patients undergoing the procedure achieved a satisfactory eyelid appearance immediately after surgery. Patients were followed up for 3 to 12 months. All patients had significant improvement in upper eyelid skin laxity and a natural shape of the eyelid. No defects that required revision surgery to improve were present, and 91.7% of the patients were satisfied with the long-term outcome. CONCLUSIONS: This systematic approach to preoperative design is simple, effective, and feasible to avoid scar exposure while addressing the lateral hood and achieve an attractive blepharoplasty appearance.

20.
Molecules ; 29(14)2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39064993

RESUMEN

Bayberry pomace, a nutrient-rich material abundant in dietary fiber (DF), has historically been underutilized due to a lack of thorough research. This study aimed to investigate the physicochemical and functional properties of the DF. Ultrasonic enzymatic treatment was performed to extract the total DF, which was then optimized to produce modified soluble dietary fiber (MSDF) and insoluble dietary fiber (MIDF). The optimized conditions yielded 15.14% of MSDF with a water-holding capacity (WHC) of 54.13 g/g. The DFs were evaluated for their structural, physicochemical, and functional properties. The MSDF showed a higher (p < 0.05) WHC, oil-holding capacity (OHC), swelling capacity (SC), cation exchange capacity (CEC), and glucose adsorption capacity (GAC) (about 14.15, 0.88, 1.23, 1.22, and 0.34 times) compared to the DF. Additionally, the MSDF showed strong, superior radical scavenging and blood sugar-lowering capabilities, with a more porous surface morphology. A Fourier-transform infrared (FT-IR) spectroscopy analysis indicated that enzymatic modification degraded the cellulose and hemicellulose, reducing the DF crystallinity. Overall, the results demonstrated that cellulase hydrolysis could effectively improve the physicochemical and functional properties of DF, thereby paving the way for its development into functional food products.


Asunto(s)
Fibras de la Dieta , Myrica , Fibras de la Dieta/análisis , Myrica/química , Hidrólisis , Espectroscopía Infrarroja por Transformada de Fourier , Celulasa/metabolismo , Celulasa/química , Fenómenos Químicos , Extractos Vegetales/química , Polisacáridos/química
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