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1.
Materials (Basel) ; 17(7)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38612119

RESUMEN

The restoration of ancient ceramics has attracted widespread attention as it can reveal the overall appearance of ancient ceramics as well as the original information and artistic charm of cultural relics. However, traditional manual restoration is constrained due to its time-consuming nature and susceptibility to damaging ancient ceramics. Herein, a three-dimensional (3D) printing technique was employed to accurately restore Chinese Yuan Dynasty Longquan celadon using hollow Al2O3 microsphere-modified 3D printing paste. The results show that the hollow Al2O3 microsphere content plays a vital role in the printability, physical properties, and firing performance of the modified 3D printing paste. The printed green bodies show no noticeable spacing or voids under moderate rheological conditions. The as-prepared ceramic body modified with 6 wt.% hollow Al2O3 microspheres and fired at 1280 °C exhibits optimal bending strength of 56.66 MPa and a relatively low density of 2.16 g∙cm-3, as well as a relatively uniform longitudinal elastic modulus and hardness along the interlayer. This 3D printing technique based on hollow Al2O3 microsphere-modified paste presents a promising pathway for achieving non-contact and damage-free restoration of cultural relics.

2.
J Agric Food Chem ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598840

RESUMEN

Sarcoplasmic calcium-binding protein (Cra a 4) from Crassostrea angulata belongs to the EF-hand superfamily, and understanding of its structure-allergenicity relationship is still insufficient. In this study, chemical denaturants were used to destroy the structure of Cra a 4, showing that disruption of the structure reduced its IgG-/IgE-binding activity. To explore which critical amino acid site affects the allergenicity of Cra a 4, the mutants were obtained by site-directed mutations in the disulfide bonds site (C97), conformational epitopes (I105, D114), or Ca2+-binding region (D106, D110) and their IgG-/IgE-binding activity was reduced significantly using serological tests. Notably, C97A had the lowest immunoreactivity. In addition, two conformational epitopes of Cra 4 were verified. Meanwhile, the increase of the α-helical content, surface hydrophobicity, and surface electrostatic potential of C97A affected its allergenicity. Overall, the understanding of the structure-allergenicity relationship of Cra a 4 allowed the development of a hypoallergenic mutant.

3.
Small ; 20(1): e2305009, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37641184

RESUMEN

As a high energy density power system, lithium-carbon dioxide (Li-CO2 ) batteries play an important role in addressing the fossil fuel crisis issues and alleviating the greenhouse effect. However, the sluggish transformation kinetic of CO2 and the difficult decomposition of discharge products impede the achievement of large capacity, small overpotential, and long life span of the batteries, which require exploring efficient catalysts to resolve these problems. In this review, the main focus is on the hot spot regulation strategies of the catalysts, which include the modulation of the active sites, the designing of microstructure, and the construction of composition. The recent progress of promising catalysis with hot spot regulated strategies is systematically addressed. Critical challenges are also presented and perspectives to provide useful guidance for the rational design of highly efficient catalysts for practical advanced Li-CO2 batteries are proposed.

4.
Environ Sci Pollut Res Int ; 30(57): 120832-120843, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37945960

RESUMEN

Machine learning models for predicting lead adsorption in biochar, based on preparation features, are currently lacking in the environmental field. Existing conventional models suffer from accuracy limitations. This study addresses these challenges by developing back-propagation neural network (BPNN) and random forest (RF) models using selected features: preparation temperature (T), specific surface area (BET), relative carbon content (C), molar ratios of hydrogen to carbon (H/C), oxygen to carbon (O/C), nitrogen to carbon (N/C), and cation exchange capacity (CEC). The RF model outperforms BPNN, improving R2 by 10%. Additional features and particle swarm optimization enhance the RF model's accuracy, resulting in an 8.3% improvement in R2, a decrease in RMSE by up to 56.1%, and a 55.7% reduction in MAE. The importance ranking of features places CEC > C > BET > O/C > H/C > N/C > T, highlighting the significance of CEC in lead adsorption. Strengthening the complexation effect may improve lead removal in biochar. This study contributes valuable insights for predicting and optimizing lead adsorption in biochar, addressing the accuracy gap in existing models. It lays the foundation for future investigations and the development of effective biochar-based solutions for sustainable lead removal in water remediation.


Asunto(s)
Carbón Orgánico , Plomo , Adsorción , Carbono , Aprendizaje Automático
5.
Sci Adv ; 9(44): eadf2664, 2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37922362

RESUMEN

The mechanical cues of the external microenvironment have been recognized as essential clues driving cell behavior. Although intracellular signals modulating cell fate during sensory epithelium development is well understood, the driving force of sensory epithelium formation remains elusive. Here, we manufactured a hybrid hydrogel with tunable mechanical properties for the cochlear organoids culture and revealed that the extracellular matrix (ECM) drives sensory epithelium formation through shifting stiffness in a stage-dependent pattern. As the driving force, moderate ECM stiffness activated the expansion of cochlear progenitor cell (CPC)-derived epithelial organoids by modulating the integrin α3 (ITGA3)/F-actin cytoskeleton/YAP signaling. Higher stiffness induced the transition of CPCs into sensory hair cells (HCs) through increasing the intracellular Ca2+ signaling mediated by PIEZO2 and then activating KLF2 to accomplish the cell specification . Our results identify the molecular mechanism of sensory epithelium formation guided by ECM mechanical force and contribute to developing therapeutic approaches for HC regeneration.


Asunto(s)
Matriz Extracelular , Transducción de Señal , Epitelio , Citoesqueleto de Actina , Diferenciación Celular
6.
BMC Oral Health ; 23(1): 501, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468947

RESUMEN

BACKGROUND: The key to the success of endogenous regeneration is to improve the homing rate of stem cells, and low-energy laser is an effective auxiliary means to promote cell migration and proliferation. The purpose of this study was to observe whether low-energy neodymium (Nd: YAG) laser with appropriate parameters can affect the proliferation and migration of periodontal ligament stem cells (PDLSCs) through SDF-1/CXCR4 pathway. METHODS: h PDLSCs were cultured and identified. CCK8 assay was used to detect the proliferation of h PDLSCs after different power (0, 0.25, 0.5, 1, and 1.5 W) Nd: YAG laser (MSP, 10 Hz, 30 s, 300 µ m) irradiation at 2th, 3rd,5th, and 7th days, and the optimal laser irradiation parameters were selected for subsequent experiments. Then, the cells were categorized into five groups: control group (C), SDF-1 group (S), AMD3100 group (A), Nd: YAG laser irradiation group (N), and Nd: YAG laser irradiation + AMD3100 group (N + A). the migration of h PDLSCs was observed using Transwell, and the SDF-1 expression was evaluated using ELISA andRT-PCR. The SPSS Statistics 21.0 software was used for statistical analysis. RESULTS: The fibroblasts cultured were identified as h PDLSCs. Compared with the C, when the power was 1 W, the proliferation rate of h PDLSCs was accelerated (P < 0.05). When the power was 1.5 W, the proliferation rate decreased (P < 0.05). When the power was 0.25 and 0.5 W, no statistically significant difference in the proliferation rate was observed (P > 0.05). The number of cell perforations values as follows: C (956.5 ± 51.74), A (981.5 ± 21.15), S (1253 ± 87.21), N (1336 ± 48.54), and N + A (1044 ± 22.13), that increased significantly in group N (P < 0.05), but decreased in group N + A (P < 0.05). The level of SDF-1 and the expression level of SDF-1 mRNA in groups N and N + A was higher than that in group C (P < 0.05) but lower than that in group A (P < 0.05). CONCLUSIONS: Nd: YAG laser irradiation with appropriate parameters provides a new method for endogenous regeneration of periodontal tissue. SDF-1/CXCR4 signaling pathway may be the mechanism of LLLT promoting periodontal regeneration.


Asunto(s)
Movimiento Celular , Láseres de Estado Sólido , Ligamento Periodontal , Células Madre , Humanos , Bencilaminas , Ligamento Periodontal/citología , Receptores CXCR4 , Células Madre/citología
7.
BMC Plant Biol ; 23(1): 318, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316771

RESUMEN

BACKGROUND: The genus Rosa (Rosaceae) contains approximately 200 species, most of which have high ecological and economic values. Chloroplast genome sequences are important for studying species differentiation, phylogeny, and RNA editing. RESULTS: In this study, the chloroplast genomes of three Rosa species, Rosa hybrida, Rosa acicularis, and Rosa rubiginosa, were assembled and compared with other reported Rosa chloroplast genomes. To investigate the RNA editing sites in R. hybrida (commercial rose cultivar), we mapped RNA-sequencing data to the chloroplast genome and analyzed their post-transcriptional features. Rosa chloroplast genomes presented a quadripartite structure and had highly conserved gene order and gene content. We identified four mutation hotspots (ycf3-trnS, trnT-trnL, psbE-petL, and ycf1) as candidate molecular markers for differentiation in the Rosa species. Additionally, 22 chloroplast genomic fragments with a total length of 6,192 bp and > 90% sequence similarity with their counterparts were identified in the mitochondrial genome, representing 3.96% of the chloroplast genome. Phylogenetic analysis including all sections and all subgenera revealed that the earliest divergence in the chloroplast phylogeny roughly distinguished species of sections Pimpinellifoliae and Rosa and subgenera Hulthemia. Moreover, DNA- and RNA-sequencing data revealed 19 RNA editing sites, including three synonymous and 16 nonsynonymous, in the chloroplast genome of R. hybrida that were distributed among 13 genes. CONCLUSIONS: The genome structure and gene content of Rosa chloroplast genomes are similar across various species. Phylogenetic analysis based on the Rosa chloroplast genomes has high resolution. Additionally, a total of 19 RNA editing sites were validated by RNA-Seq mapping in R. hybrida. The results provide valuable information for RNA editing and evolutionary studies of Rosa and a basis for further studies on genomic breeding of Rosa species.


Asunto(s)
Genoma del Cloroplasto , Rosa , Rosa/genética , Genoma del Cloroplasto/genética , Filogenia , Edición de ARN/genética , Fitomejoramiento , ARN
8.
Mol Cell ; 83(13): 2316-2331.e7, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37390815

RESUMEN

The diabetes-cancer association remains underexplained. Here, we describe a glucose-signaling axis that reinforces glucose uptake and glycolysis to consolidate the Warburg effect and overcome tumor suppression. Specifically, glucose-dependent CK2 O-GlcNAcylation impedes its phosphorylation of CSN2, a modification required for the deneddylase CSN to sequester Cullin RING ligase 4 (CRL4). Glucose, therefore, elicits CSN-CRL4 dissociation to assemble the CRL4COP1 E3 ligase, which targets p53 to derepress glycolytic enzymes. A genetic or pharmacologic disruption of the O-GlcNAc-CK2-CSN2-CRL4COP1 axis abrogates glucose-induced p53 degradation and cancer cell proliferation. Diet-induced overnutrition upregulates the CRL4COP1-p53 axis to promote PyMT-induced mammary tumorigenesis in wild type but not in mammary-gland-specific p53 knockout mice. These effects of overnutrition are reversed by P28, an investigational peptide inhibitor of COP1-p53 interaction. Thus, glycometabolism self-amplifies via a glucose-induced post-translational modification cascade culminating in CRL4COP1-mediated p53 degradation. Such mutation-independent p53 checkpoint bypass may represent the carcinogenic origin and targetable vulnerability of hyperglycemia-driven cancer.


Asunto(s)
Neoplasias , Proteína p53 Supresora de Tumor , Animales , Ratones , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Glucosa , Ubiquitina-Proteína Ligasas/metabolismo , Carcinogénesis/genética , Transformación Celular Neoplásica/genética
9.
Nat Struct Mol Biol ; 30(6): 753-760, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37081318

RESUMEN

SIN3-HDAC (histone deacetylases) complexes have important roles in facilitating local histone deacetylation to regulate chromatin accessibility and gene expression. Here, we present the cryo-EM structure of the budding yeast SIN3-HDAC complex Rpd3L at an average resolution of 2.6 Å. The structure reveals that two distinct arms (ARM1 and ARM2) hang on a T-shaped scaffold formed by two coiled-coil domains. In each arm, Sin3 interacts with different subunits to create a different environment for the histone deacetylase Rpd3. ARM1 is in the inhibited state with the active site of Rpd3 blocked, whereas ARM2 is in an open conformation with the active site of Rpd3 exposed to the exterior space. The observed asymmetric architecture of Rpd3L is different from those of available structures of other class I HDAC complexes. Our study reveals the organization mechanism of the SIN3-HDAC complex and provides insights into the interaction pattern by which it targets histone deacetylase to chromatin.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomycetales , Factores de Transcripción/metabolismo , Proteínas Represoras/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Cromatina , Histona Desacetilasas/genética
10.
Stem Cell Reports ; 18(1): 319-336, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36584686

RESUMEN

Functional cochlear hair cells (HCs) innervated by spiral ganglion neurons (SGNs) are essential for hearing, whereas robust models that recapitulate the peripheral auditory circuity are still lacking. Here, we developed cochlear organoids with functional peripheral auditory circuity in a staging three-dimensional (3D) co-culture system by initially reprogramming cochlear progenitor cells (CPCs) with increased proliferative potency that could be long-term expanded, then stepwise inducing the differentiation of cochlear HCs, as well as the outgrowth of neurites from SGNs. The function of HCs and synapses within organoids was confirmed by a series of morphological and electrophysiological evaluations. Single-cell mRNA sequencing revealed the differentiation trajectories of CPCs toward the major cochlear cell types and the dynamic gene expression during organoid HC development, which resembled the pattern of native HCs. We established the cochlear organoids with functional synapses for the first time, which provides a platform for deciphering the mechanisms of sensorineural hearing loss.


Asunto(s)
Cóclea , Ganglio Espiral de la Cóclea , Neuronas/metabolismo , Neuritas/metabolismo , Organoides
11.
Neuropathology ; 43(1): 100-103, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35989547

RESUMEN

Primary central nervous system T-cell lymphoma (T-PCNSL) is a rare neoplasm, and its underlying genetic features are poorly understood. Herein, we present the case of a 64-year-old man with T-PCNSL who presented with left-side limb weakness. Brain magnetic resonance imaging revealed a right parietal space-occupying lesion. Immunohistochemically, the tumor was positive for CD3, CD4, CD5, CD8, and CD56, and the Ki-67 labeling index was approximately 20%. These pathological features are consistent with those of T-cell lymphoma. Whole exome sequencing was performed, and we found a variant in the ACSS3 gene that could be related to disease pathogenesis. Our findings may help advance our understanding of the molecular pathogenesis of T-PCNSL. Further molecular analysis of such cases could help to improve adjuvant molecular diagnostic methods and targeted therapies for T-PCNSL.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Linfoma de Células T , Masculino , Humanos , Persona de Mediana Edad , Secuenciación del Exoma , Neoplasias del Sistema Nervioso Central/patología , Linfoma de Células T/genética , Encéfalo/patología , Genómica
12.
Angew Chem Int Ed Engl ; 61(52): e202209945, 2022 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-36305862

RESUMEN

The post-translational modifications (PTMs) on the tail of histone H3 control chromatin structure and influence epigenetics and gene expression. The current chemical methods including unnatural amino acid incorporation and protein splicing enable preparations of the histone with diverse PTMs in cellular contexts, but they are not applicable to edit native chromatin. The manipulation of histone-modifying enzymes alter the endogenous histone PTMs but the lack of specificity of most histone-modifying enzymes prevents precise control of specific H3 tail PTM patterns. Here we report a new method to edit the N-tail of histone H3 via sortase mediated metathesis (SMM). The sortase can install desired PTM patterns into histone H3 on nucleosomes in vitro and in cellulo. This study expands the application scope of sortase from ligation to metathesis in live cells using cell-penetrating peptides (CPPs). In addition, it offers a strategy to edit PTMs of cellular histone H3 with potential for the development of precise epigenome editing.


Asunto(s)
Cromatina , Histonas , Histonas/química , Procesamiento Proteico-Postraduccional , Nucleosomas , Código de Histonas
13.
BMC Oral Health ; 22(1): 409, 2022 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-36123683

RESUMEN

BACKGROUND: The study aimed to observe the effects of a Twinlight laser on the titanium surface proliferation of inflammatory Mesenchymal stem cells (MSCs), inflammatory cytokine expression, and osteogenic differentiation. METHODS: The MSCs were collected from bone tissue of healthy individuals.The cellular inflammatory model was established with 1 µg/mL lipopolysaccharide (LPS).Under the cellular inflammatory model,divided into five groups: the normal control group (C); the inflammatory control group (L); Er:YAG laser group (L + E); Nd:YAG laser group (L + N); Er:YAG laser and Nd:YAG laser group (L + E + N). The treated cells were inoculated onto titanium disks.The normal and inflammatory MSCs on the surface of titanium surface were examined by CCK-8, scanning election microscopy (SEM), quantitative real-time polymerase chain reaction (qRT­PCR) and other methods for their proliferation, growth pattern, expression of inflammatory factors Interleukin-6 (IL-6), Interleukin-8 (IL-8) and osteogenic genes Runx2 (Runt-related transcription factor 2) and alkaline phosphatase (ALP), providing the theoretical basis and experimental data for the Twinlight laser-assisted treatment of peri-implantitis. Statistical analyses were performed using a Student's t test with SPSS 17.0 software. RESULTS: Through observation using SEM, the cell densities of the L + E + N, L + E, and L + N groups were similar, but cell bodies in the L + E + N group were fuller and each had more than two pseudopodia. The expression level of IL-6 mRNA in the L, L + N, L + E, and L + E + N groups was higher than in group C (P < 0.05), and the expression level of IL-8 mRNA in the L + E + N group was significantly lower than in group L (P < 0.0001). On day 7, the expression level of ALP mRNA in the L, L + N, L + E, and L + E + N groups was lower than in group C (P < 0.05). On day 14, there was no significant difference in the expression level of ALP mRNA among the L + N, L + E + N, and C groups (P > 0.05). On day 7, the expression level of RUNX2 mRNA in the L + E + N group was higher than in group L (P < 0.001). On day 14, the expression level of RUNX2 mRNA in the L + E + N group was higher than in group L (P < 0.01). CONCLUSION: Twinlight laser treatment promoted cell proliferation, inhibited the expression of inflammatory cytokines, and effectively enhanced the osteogenic differentiation of cells on a titanium surface.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Fosfatasa Alcalina/metabolismo , Proliferación Celular , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Rayos Láser , Lipopolisacáridos/farmacología , ARN Mensajero/metabolismo , Sincalida/metabolismo , Sincalida/farmacología , Titanio/farmacología
14.
Lasers Med Sci ; 37(8): 3177-3182, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35727393

RESUMEN

This study investigated the feasibility of using an Er:YAG laser to pretreat glass-ceramic surface and evaluate the effect of the treatment on the bonding strength and marginal adaptation between glass-ceramic and dentin. Glass-ceramic samples (CEREC Blocs) and third molars were cut into 6 mm × 6 mm × 2 mm plates. Thirty ceramic plates were randomly divided into 5 groups: group A (control), group B (pretreated with 9.6% hydrofluoric acid [HF]), group C (pretreated with the Er:YAG laser at 300 mJ and 15 Hz), group D (pretreated with the Er:YAG laser at 400 mJ and 15 Hz), and group E (pretreated with the Er:YAG laser at 500 mJ and 15 Hz). The surface morphologies of the samples in each group were studied under a scanning electron microscope, and the sample displaying optimal etching parameters was selected for subsequent experiments. Based on the surface treatments, 30 ceramic and dentin plates were randomly allocated into 3 groups: the control, laser, and acid-etching groups. After bonding a ceramic plate to a dentin plate, the microleakage and bonding strength were measured, and the pretreatment effects of the Er:YAG laser and 9.6% HF were compared. Group E exhibited an etching effect that was more pronounced and uniform than that in groups C and D. Microleakage and bonding strength analyses revealed that the laser and acid-etching groups differed significantly from the control group in dye penetration depth and shear strength (P < 0.05), although the laser and acid-etching groups did not differ from each other. Both 9.6% hydrofluoric acid and Er:YAG laser pretreatments can coarsen glass-ceramic surfaces, improve the marginal adaptation and bonding strength between the glass-ceramic and dentin, and decrease microleakage of the materials. The two treatments showed no apparent differences in pretreatment outcomes.


Asunto(s)
Recubrimiento Dental Adhesivo , Láseres de Estado Sólido , Cerámica , Ácido Fluorhídrico , Ensayo de Materiales , Cementos de Resina/farmacología , Resistencia al Corte , Propiedades de Superficie
15.
Bioresour Technol ; 352: 127092, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35367323

RESUMEN

This study evaluated the effectiveness of shrimp shell biochar (SBC) and nickel (Ni) loaded SBC in increasing methane yield during anaerobic digestion of food waste. The results indicated that the methane yields of control (without SBC), SBC, SBC loaded with the low concentration of Ni, and SBC loaded with the high concentration of Ni were 81.8, 116.1, 134.7, and 99.2 mL/(g·VS), respectively. SBC promoted the efficiency and stability of the whole anaerobic digestion process including hydrolysis, volatile fatty acid conversion and methanogenesis. While the invigorating effect of loaded Ni at the low concentration of 0.88 mg/g was mainly concentrated in methanogenesis, the inhibition effect of the high Ni concentration was comprehensive. SBC helped Methanosarcina proliferation, and low concentration Ni promoted the number and activity of Methanosarcina and Methanosaeta. The results show that biochar loaded with a low level of trace elements such as Ni can promote the anaerobic digestion process.


Asunto(s)
Eliminación de Residuos , Oligoelementos , Anaerobiosis , Reactores Biológicos , Carbón Orgánico , Digestión , Alimentos , Metano , Níquel
17.
Ambio ; 51(7): 1739-1751, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35230659

RESUMEN

Watershed and catchment area-based water quality management are important methods for comprehensive management of rivers and lakes. The impacts of land use/land cover (LULC) on river water quality vary with spatial scales, such as watersheds, catchments, and riparian zones. Achieving an effective spatial scale relationship between LULC and water quality, determining priority management areas, and reaching sustainable development of large estuarine deltas remain problematic. In this study, buffering analysis on the water quality data of the Yangtze River Estuary from 2009 to 2018 was conducted based on LULC, and the priority management areas of the basin were identified. Also, we infer that future river restoration or management efforts should focus on priority management area construction of a 1500 m riparian zone and a 150 km reach zone. Conclusively, establishing a priority management area within the effective buffer zone is key to watershed water quality management.


Asunto(s)
Estuarios , Ríos , Monitoreo del Ambiente/métodos , Lagos , Calidad del Agua
18.
J Am Chem Soc ; 144(8): 3360-3364, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35175758

RESUMEN

We describe a new method to produce histone H2B by semisynthesis with an engineered sortase transpeptidase. N-Terminal tail site-specifically modified acetylated, lactylated, and ß-hydroxybutyrylated histone H2Bs were incorporated into nucleosomes and investigated as substrates of histone deacetylase (HDAC) complexes and sirtuins. A wide range of rates and site-specificities were observed by these enzyme forms suggesting distinct biological roles in regulating chromatin structure and epigenetics.


Asunto(s)
Histonas , Sirtuinas , Cromatina , Histona Desacetilasas/genética , Histonas/química , Nucleosomas
19.
Nat Commun ; 13(1): 959, 2022 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-35181650

RESUMEN

Record rainfall and severe flooding struck eastern China in the summer of 2020. The extreme summer rainfall occurred during the COVID-19 pandemic, which started in China in early 2020 and spread rapidly across the globe. By disrupting human activities, substantial reductions in anthropogenic emissions of greenhouse gases and aerosols might have affected regional precipitation in many ways. Here, we investigate such connections and show that the abrupt emissions reductions during the pandemic strengthened the summer atmospheric convection over eastern China, resulting in a positive sea level pressure anomaly over northwestern Pacific Ocean. The latter enhanced moisture convergence to eastern China and further intensified rainfall in that region. Modeling experiments show that the reduction in aerosols had a stronger impact on precipitation than the decrease of greenhouse gases did. We conclude that through abrupt emissions reductions, the COVID-19 pandemic contributed importantly to the 2020 extreme summer rainfall in eastern China.


Asunto(s)
Aerosoles/análisis , COVID-19/epidemiología , Gases de Efecto Invernadero/análisis , Lluvia , Emisiones de Vehículos/análisis , China/epidemiología , Inundaciones , Actividades Humanas/estadística & datos numéricos , Humanos , Pandemias/estadística & datos numéricos , SARS-CoV-2 , Estaciones del Año
20.
Med Sci Monit ; 28: e932191, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34983919

RESUMEN

BACKGROUND This study aimed to compare the effectiveness of subgingival scaling and root planing with the Twinlight laser, Er: YAG laser, and hand instrumentation on the removal of endotoxin and attachment of human gingival fibroblasts (HGFs) to cementum surfaces in vitro. MATERIAL AND METHODS Single-rooted teeth extracted for periodontal disease were collected and divided into 3 groups: group A, root planing with Gracey curet no. 5/6; group B, irradiation with Er: YAG laser; group C, irradiation with Er: YAG laser and Nd: YAG laser. Endotoxins were determined by the limulus amebocyte lysate test. Cell attachment and proliferation of HGFs on root specimens were evaluated by cell counting kit-8 assay. The root surface and cell morphology were observed by scanning electron microscope. RESULTS A flat root surface with scratches was found in group A, Group B had a homogeneous rough morphology without carbonization, and group C had a non-homogeneous rough morphology with ablation. The endotoxin concentration was highest in group A (P<0.05) and lowest in group C (P>0.05). HGFs cultured in group B showed significantly increased adhesion and proliferation compared with groups A and C (P<0.05). HGFs in group B were well attached, covered densely by pseudopodia. HGFs in group A were round with poor extension and short pseudopodia, while the cells in the group C were in narrow, triangular, or polygonal shapes. CONCLUSIONS Twinlight laser-assisted periodontal treatment effectively improved the biocompatibility of root surface and promoted the attachment and proliferation of fibroblasts by removing calculus and reducing the concentration of endotoxins.


Asunto(s)
Fibroblastos/fisiología , Encía , Terapia por Láser , Láseres de Estado Sólido/uso terapéutico , Enfermedades Periodontales , Aplanamiento de la Raíz/métodos , Adhesión Celular , Encía/microbiología , Encía/patología , Humanos , Terapia por Láser/instrumentación , Terapia por Láser/métodos , Microscopía Electrónica de Rastreo/métodos , Enfermedades Periodontales/microbiología , Enfermedades Periodontales/fisiopatología , Enfermedades Periodontales/terapia , Propiedades de Superficie
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