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1.
EMBO J ; 42(21): e114220, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37691541

RESUMEN

DELLA proteins are master regulators of gibberellic acid (GA) signaling through their effects on gene expression. Enhanced DELLA accumulation in rice and wheat varieties has greatly contributed to grain yield increases during the green revolution. However, the molecular basis of DELLA-mediated gene repression remains elusive. In this work, we show that the rice DELLA protein SLENDER RICE1 (SLR1) forms a tripartite complex with Polycomb-repressive complex 2 (PRC2) and the histone deacetylase HDA702 to repress downstream genes by establishing a silent chromatin state. The slr1 mutation and GA signaling resulted in dissociation of PRC2 and HDA702 from GA-inducible genes. Loss-of-function or downregulation of the chromatin regulators impaired SLR1-dependent histone modification and gene repression. Time-resolved analysis of GA signaling revealed that GA-induced transcriptional activation was associated with a rapid increase of H3K9ac followed by H3K27me3 removal. Collectively, these results establish a general epigenetic mechanism for DELLA-mediated gene repression and reveal details of the chromatin dynamics during transcriptional activation stimulated by GA signaling.


Asunto(s)
Giberelinas , Oryza , Giberelinas/metabolismo , Giberelinas/farmacología , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Expresión Génica , Cromatina/genética , Cromatina/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
Plant Cell ; 34(8): 2969-2988, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35512211

RESUMEN

Polycomb repressive complex 2 (PRC2), which mediates the deposition of H3K27me3 histone marks, is important for developmental decisions in animals and plants. In the shoot apical meristem (SAM), Three Amino acid Loop Extension family KNOTTED-LIKE HOMEOBOX /BEL-like (KNOX/BELL) transcription factors are key regulators of meristem cell pluripotency and differentiation. Here, we identified a PRC2-associated coiled-coil protein (PACP) that interacts with KNOX/BELL transcription factors in rice (Oryza sativa) shoot apex cells. A loss-of-function mutation of PACP resulted in differential gene expression similar to that observed in PRC2 gene knockdown plants, reduced H3K27me3 levels, and reduced genome-wide binding of the PRC2 core component EMF2b. The genomic binding of PACP displayed a similar distribution pattern to EMF2b, and genomic regions with high PACP- and EMF2b-binding signals were marked by high levels of H3K27me3. We show that PACP is required for the repression of cell differentiation-promoting genes targeted by a rice KNOX1 protein in the SAM. PACP is involved in the recruitment or stabilization of PRC2 to genes targeted by KNOX/BELL transcription factors to maintain H3K27me3 and gene repression in dividing cells of the shoot apex. Our results provide insight into PRC2-mediated maintenance of H3K27me3 and the mechanism by which KNOX/BELL proteins regulate SAM development.


Asunto(s)
Oryza , Complejo Represivo Polycomb 2 , Animales , Diferenciación Celular/genética , Genes Homeobox , Histonas/genética , Histonas/metabolismo , Meristema/metabolismo , Oryza/metabolismo , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo
3.
Nucleic Acids Res ; 51(19): 10795-10807, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37757856

RESUMEN

As CRISPR technology is promoted to more fine-divided molecular biology applications, its inherent performance finds it increasingly difficult to cope with diverse needs in these different fields, and how to more accurately control the performance has become a key issue to develop CRISPR technology to a new stage. Herein, we propose a CRISPR/Cas12a regulation strategy based on the powerful programmability of nucleic acid nanotechnology. Unlike previous difficult and rigid regulation of core components Cas nuclease and crRNA, only a simple switch of different external RNA accessories is required to change the reaction kinetics or thermodynamics, thereby finely and almost steplessly regulating multi-performance of CRISPR/Cas12a including activity, speed, specificity, compatibility, programmability and sensitivity. In particular, the significantly improved specificity is expected to mark advance the accuracy of molecular detection and the safety of gene editing. In addition, this strategy was applied to regulate the delayed activation of Cas12a, overcoming the compatibility problem of the one-pot assay without any physical separation or external stimulation, and demonstrating great potential for fine-grained control of CRISPR. This simple but powerful CRISPR regulation strategy without any component modification has pioneering flexibility and versatility, and will unlock the potential for deeper applications of CRISPR technology in many finely divided fields.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Sistemas CRISPR-Cas/genética , Endonucleasas/genética , ARN/genética , ARN Guía de Sistemas CRISPR-Cas
4.
Lancet Oncol ; 25(2): 184-197, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38211606

RESUMEN

BACKGROUND: Triple-negative breast cancers display heterogeneity in molecular drivers and immune traits. We previously classified triple-negative breast cancers into four subtypes: luminal androgen receptor (LAR), immunomodulatory, basal-like immune-suppressed (BLIS), and mesenchymal-like (MES). Here, we aimed to evaluate the efficacy and safety of subtyping-based therapy in the first-line treatment of triple-negative breast cancer. METHODS: FUTURE-SUPER is an ongoing, open-label, randomised, controlled phase 2 trial being conducted at Fudan University Shanghai Cancer Center (FUSCC), Shanghai, China. Eligible participants were females aged 18-70 years, with an Eastern Cooperative Oncology Group performance status of 0-1, and histologically confirmed, untreated metastatic or recurrent triple-negative breast cancer. After categorising participants into five cohorts according to molecular subtype and genomic biomarkers, participants were randomly assigned (1:1) with a block size of 4, stratified by subtype, to receive, in 28-day cycles, nab-paclitaxel (100 mg/m2, intravenously on days 1, 8, and 15) alone (control group) or with a subtyping-based regimen (subtyping-based group): pyrotinib (400 mg orally daily) for the LAR-HER2mut subtype, everolimus (10 mg orally daily) for the LAR-PI3K/AKTmut and MES-PI3K/AKTmut subtypes, camrelizumab (200 mg intravenously on days 1 and 15) and famitinib (20 mg orally daily) for the immunomodulatory subtype, and bevacizumab (10 mg/kg intravenously on days 1 and 15) for the BLIS/MES-PI3K/AKTWT subtype. The primary endpoint was investigator-assessed progression-free survival for the pooled subtyping-based group versus the control group in the intention-to-treat population (all randomly assigned participants). Safety was analysed in all patients with safety records who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (NCT04395989). FINDINGS: Between July 28, 2020, and Oct 16, 2022, 139 female participants were enrolled and randomly assigned to the subtyping-based group (n=69) or control group (n=70). At the data cutoff (May 31, 2023), the median follow-up was 22·5 months (IQR 15·2-29·0). Median progression-free survival was significantly longer in the pooled subtyping-based group (11·3 months [95% CI 8·6-15·2]) than in the control group (5·8 months [4·0-6·7]; hazard ratio 0·44 [95% CI 0·30-0·65]; p<0·0001). The most common grade 3-4 treatment-related adverse events were neutropenia (21 [30%] of 69 in the pooled subtyping-based group vs 16 [23%] of 70 in the control group), anaemia (five [7%] vs none), and increased alanine aminotransferase (four [6%] vs one [1%]). Treatment-related serious adverse events were reported for seven (10%) of 69 patients in the subtyping-based group and none in the control group. No treatment-related deaths were reported in either group. INTERPRETATION: These findings highlight the potential clinical benefits of using molecular subtype-based treatment optimisation in patients with triple-negative breast cancer, suggesting a path for further clinical investigation. Phase 3 randomised clinical trials assessing the efficacy of subtyping-based regimens are now underway. FUNDING: National Natural Science Foundation of China, Natural Science Foundation of Shanghai, Shanghai Hospital Development Center, and Jiangsu Hengrui Pharmaceuticals. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Proteínas Proto-Oncogénicas c-akt , Fosfatidilinositol 3-Quinasas/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , China , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
5.
Med Res Rev ; 44(3): 1189-1220, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38178560

RESUMEN

Inflammation is the body's defense response to exogenous or endogenous stimuli, involving complex regulatory mechanisms. Discovering anti-inflammatory drugs with both effectiveness and long-term use safety is still the direction of researchers' efforts. The inflammatory pathway was initially identified to be involved in tumor metastasis and HIV infection. However, research in recent years has proved that the CXC chemokine receptor type 4 (CXCR4)/CXC motif chemokine ligand 12 (CXCL12) axis plays a critical role in the upstream of the inflammatory pathway due to its chemotaxis to inflammatory cells. Blocking the chemotaxis of inflammatory cells by CXCL12 at the inflammatory site may block and alleviate the inflammatory response. Therefore, developing CXCR4 antagonists has become a novel strategy for anti-inflammatory therapy. This review aimed to systematically summarize and analyze the mechanisms of action of the CXCR4/CXCL12 axis in more than 20 inflammatory diseases, highlighting its crucial role in inflammation. Additionally, the anti-inflammatory activities of CXCR4 antagonists were discussed. The findings might help generate new perspectives for developing anti-inflammatory drugs targeting the CXCR4/CXCL12 axis.


Asunto(s)
Infecciones por VIH , Receptores CXCR4 , Humanos , Infecciones por VIH/tratamiento farmacológico , Quimiocina CXCL12 , Inflamación/tratamiento farmacológico , Antiinflamatorios/farmacología , Descubrimiento de Drogas
6.
Immunology ; 172(2): 295-312, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38453210

RESUMEN

Hyperactivation of the cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signalling pathway has been shown to be associated with the development of a variety of inflammatory diseases, and the discovery of an inhibitor of the cGAS-STING signalling pathway holds great promise in the therapeutic interventions. Epimedium flavonoid (EF), a major active ingredient isolated from the medicinal plant Epimedium, has been reported to have good anti-inflammatory activity, but its exact mechanism of action remains unclear. In the present study, we found that EF in mouse bone marrow-derived macrophages (BMDMs), THP-1 (Tohoku Hospital Pediatrics-1) as well as in human peripheral blood mononuclear cells (hPBMC) inhibited the activation of the cGAS-STING signalling pathway, which subsequently led to a decrease in the expression of type I interferon (IFN-ß, CXCL10 and ISG15) and pro-inflammatory cytokines (IL-6 and TNF-α). Mechanistically, EF does not affect STING oligomerization, but inhibits the formation of functional STING signalosome by attenuating the interaction of interferon regulatory factor 3 (IRF3) with STING and TANK-binding kinase 1 (TBK1). Importantly, in vivo experiments, EF has shown promising therapeutic effects on inflammatory diseases mediated by the cGAS-STING pathway, which include the agonist model induced by DMXAA stimulation, the autoimmune inflammatory disease model induced by three prime repair exonuclease 1 (Trex1) deficiency, and the non-alcoholic steatohepatitis (NASH) model induced by a pathogenic amino acid and choline deficiency diet (MCD). To summarize, our study suggests that EF is a potent potential inhibitor component of the cGAS-STING signalling pathway for the treatment of inflammatory diseases mediated by the cGAS-STING signalling pathway.


Asunto(s)
Epimedium , Flavonoides , Proteínas de la Membrana , Nucleotidiltransferasas , Transducción de Señal , Nucleotidiltransferasas/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Transducción de Señal/efectos de los fármacos , Humanos , Ratones , Flavonoides/farmacología , Epimedium/química , Factor 3 Regulador del Interferón/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/efectos de los fármacos , Ratones Endogámicos C57BL , Citocinas/metabolismo , Células THP-1 , Proteínas Serina-Treonina Quinasas/metabolismo , Antiinflamatorios/farmacología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/efectos de los fármacos
7.
Small ; 20(16): e2308806, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38010127

RESUMEN

Developing high-performance infrared (IR) nonlinear optical (NLO) materials is urgent but challenging due to the competition between NLO coefficient and bandgap in one compound. Herein, by coupling NLO-active [BS3] planar units and halide-centered polycations, six new metal thioborate halides ABa3B2S6X (A = Rb, Cs; X = Cl, Br, I) composed of zero-dimensional [XBamRbn/Csn] polycations and [BS3] units, belonging to a new A I B 3 II C 2 III Q 6 VI X VII ${\mathrm{A}}^{\mathrm{I}}{\mathrm{B}}_{3}^{\mathrm{II}}{\mathrm{C}}_{2}^{\mathrm{III}}{\mathrm{Q}}_{6}^{\mathrm{VI}}{\mathrm{X}}^{\mathrm{VII}}$ family, are rationally designed and fabricated. The compounds show an interesting structural transition from Pbcn (ABa3B2S6Cl) to Cmc21 (ABa3B2S6Br and ABa3B2S6I) driven by the clamping effect of polycationic frameworks. ABa3B2S6Br and ABa3B2S6I are the first series metal thioborate halide IR NLO materials, and the introduction of [BS3] unit effectively widens the bandgap of planar unit-constructed chalcogenides. ABa3B2S6Br and ABa3B2S6I, exhibiting wide bandgaps (3.55-3.60 eV), high laser-induced damage thresholds (≈ 6 × AgGaS2), and strong SHG effects (0.5-0.6 × AgGaS2) with phase-matching behaviors, are the promising IR NLO candidates for high-power laser applications. The results enrich the chemical and structural diversity of boron chemistry and give some insights into the design of new IR NLO materials with planar units.

8.
Small ; 20(25): e2308724, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38229571

RESUMEN

In future information storage and processing, magnonics is one of the most promising candidates to replace traditional microelectronics. Yttrium iron garnet (YIG) films with perpendicular magnetic anisotropy (PMA) have aroused widespread interest in magnonics. Obtaining strong PMA in a thick YIG film with a small lattice mismatch (η) has been fascinating but challenging. Here, a novel strategy is proposed to reduce the required minimum strain value for producing PMA and increase the maximum thickness for maintaining PMA in YIG films by slight oxygen deficiency. Strong PMA is achieved in the YIG film with an η of only 0.4% and a film thickness up to 60 nm, representing the strongest PMA for such a small η reported so far. Combining transmission electron microscopy analyses, magnetic measurements, and a theoretical model, it is demonstrated that the enhancement of PMA physically originates from the reduction of saturation magnetization and the increase of magnetostriction coefficient induced by oxygen deficiency. The Gilbert damping values of the 60-nm-thick YIG films with PMA are on the order of 10-4. This strategy improves the flexibility for the practical applications of YIG-based magnonic devices and provides promising insights for the theoretical understanding and the experimental enhancement of PMA in garnet films.

9.
Opt Express ; 32(4): 6266-6276, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439334

RESUMEN

Augmented reality (AR) display, as a next-generation innovative technology, is revolutionizing the ways of perceiving and communicating by overlaying virtual images onto real-world scenes. However, the current AR devices are often bulky and cumbersome, posing challenges for long-term wearability. Metasurfaces have flexible capabilities of manipulating light waves at subwavelength scales, making them as ideal candidates for replacing traditional optical elements in AR display devices. In this work, we propose and fabricate what we believe is a novel reflective polarization multiplexing gradient metasurface based on propagation phase principle to replace the optical combiner element in traditional AR display devices. Our designed metasurface exhibits different polarization modulations for reflected and transmitted light, enabling efficient deflection of reflected light while minimizing the impact on transmitted light. This work reveals the significant potential of metasurfaces in next-generation optical display systems and provides a reliable theoretical foundation for future integrated waveguide schemes, driving the development of next-generation optical display products towards lightweight and comfortable.

10.
Plant Cell ; 33(12): 3721-3742, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34498077

RESUMEN

Plant SNF1-Related Kinase1 (SnRK1) is an evolutionarily conserved energy-sensing protein kinase that orchestrates transcriptional networks to maintain cellular energy homeostasis when energy supplies become limited. However, the mechanism by which SnRK1 regulates this gene expression switch to gauge cellular energy status remains largely unclear. In this work, we show that the rice histone H3K27me3 demethylase JMJ705 is required for low energy stress tolerance in rice plants. The genetic inactivation of JMJ705 resulted in similar effects as those of the rice snrk1 mutant on the transcriptome, which impairs not only the promotion of the low energy stress-triggered transcriptional program but also the repression of the program under an energy-sufficient state. We show that the α-subunit of OsSnRK1 interacts with and phosphorylates JMJ705 to stimulate its H3K27me3 demethylase activity. Further analysis revealed that JMJ705 directly targets a set of low energy stress-responsive transcription factor genes. These results uncover the chromatin mechanism of SnRK1-regulated gene expression in both energy-sufficient and -limited states in plants and suggest that JMJ705 functions as an upstream regulator of the SnRK1α-controlled transcriptional network.


Asunto(s)
Metabolismo Energético , Homeostasis/genética , Oryza/fisiología , Proteínas de Plantas/genética , Transcripción Genética/fisiología , Oryza/genética
11.
Opt Lett ; 49(1): 165-168, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134178

RESUMEN

Near-unity circular dichroism (CD) with high quality (Q)-factors has wide applications in chiral lasers, modulators, detectors, etc. In this work, we firstly suggest a feasible approach to realize near-unity CD (∼0.94) with a high Q-factor (>2 × 104) supported by a toroidal dipole (TD) empowered superchiral quasi-bound states in the continuum (BICs) metasurface. Based on intensity, excellent electrical switching is achieved by adjusting the Fermi energy of the graphene on the metasurface. High refractive index sensitivity (136.2 nm/RIU) and figure of merit (1135 RIU-1) demonstrate its superior chiral sensing detection performance. Moreover, the near-unity CD displays a large robustness to the asymmetry offset. Our work paves a feasible avenue for well-designed superchiral quasi-BIC metasurfaces with high Q-factor near-unity CD for chiral applications in electrically tunable modulators, switches, sensors, etc.

12.
FASEB J ; 37(12): e23290, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37921465

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disease where abnormal amyloidogenic processing of amyloid-ß precursor protein (APP) occurs and has been linked to neuronal dysfunction. Hypometabolism of glucose in the brain can lead to synaptic loss and neuronal death, which in turn exacerbates energy deficiency and amyloid-ß peptide (Aß) accumulation. Lactate produced by anaerobic glycolysis serves as an energy substrate supporting neuronal function and facilitating neuronal repair. Vestigial-like family member 4 (VGLL4) has been recognized as a key regulator of the hypoxia-sensing pathway. However, the role of VGLL4 in AD remains unexplored. Here, we reported that the expression of VGLL4 protein was significantly decreased in the brain tissue of AD model mice and AD model cells. We further found that overexpression of VGLL4 reduced APP amyloidogenic processing and ameliorated neuronal synaptic damage. Notably, we identified a compromised hypoxia-sensitive capability of LDHA regulated by VGLL4 in the context of AD. Upregulation of VGLL4 increased the response of LDHA to hypoxia and enhanced the expression levels of LDHA and lactate by inhibiting the ubiquitination and degradation of LDHA. Furthermore, the inhibition of lactate production by using sodium oxamate, an inhibitor of LDHA, suppressed the neuroprotective function of VGLL4 by increasing APP amyloidogenic processing. Taken together, our findings demonstrate that VGLL4 exerts a neuroprotective effect by upregulating LDHA expression and consequently promoting lactate production. Thus, this study suggests that VGLL4 may be a novel player involved in molecular mechanisms relevant for ameliorating neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Ratones , Animales , Enfermedad de Alzheimer/metabolismo , Ácido Láctico , Precursor de Proteína beta-Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Hipoxia , Ratones Transgénicos , Factores de Transcripción
13.
Langmuir ; 40(14): 7520-7531, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38552210

RESUMEN

This study investigated the reaction mechanism of aluminum-magnesium (Al-Mg) alloy particles with water (Al-Mg/H2O) through thermogravimetric analysis-differential scanning calorimetry experiments and kinetic analysis using isoconversional methods and the master plot technique to determine the reaction mechanism function, with the aim of providing insights to support metal powder/water ramjet engine design and combustion characteristics. The results showed that the Al-Mg/H2O reaction occurred in two distinct stages, with stage 1 primarily involving the reaction of Mg elements in the L(Al-Mg) alloy with water while Al played a leading role in stage 2. Notably, the reaction temperatures of Al-Mg particles were significantly lower than those for either Al or Mg particles alone in a water vapor environment. Additionally, the activation energy of stage 1 was lower than that for the individual Al and Mg particles and decreased with increasing Mg content in stage 2. Furthermore, the concentration of Mg in the alloy was found to have a major influence on the reaction mechanism, which followed a random nucleation and growth model. Overall, this work elucidated an alternating endothermic and exothermic staged reaction process for Al-Mg/H2O dominated first by Mg and then Al with kinetic insights providing theoretical support for optimizing Al-Mg alloy compositions for improved ignition and combustion performance in metal powder/water ramjet engines.

14.
Fish Shellfish Immunol ; 144: 109258, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38042226

RESUMEN

Large yellow croaker (Larimichthys crocea) is the most productive marine fish in China. Cryptocaryon irritans is an extremely destructive parasite that causes great economic losses in large yellow croaker aquaculture industry. Therefore, it is very necessary to study the immune response of large yellow croaker in response to C. irritans infection. In this study, the transcriptomic profiles of large yellow croaker were sequenced and analyzed in the brain and head kidney at 72 h after C. irritans infection. Cytokines and chemokines related terms were significantly enriched based on the GO enrichment of down-regulated differentially expressed genes (DEGs) from the head kidney. Meanwhile, cytokine-cytokine receptor interaction was significantly enriched based on the KEGG enrichment of up-regulated DEGs from the brain and down-regulated DEGs from the head kidney, respectively. Moreover, the majority of inflammation-related DEGs were significantly up-regulated in the brain, but distinctly down-regulated in the head kidney. These results showed that the brain and head kidney might play different roles against C. irritans infection, and the inflammatory response of large yellow croaker may be restrained during C. irritans infection. Taken together, the transcriptomic analyses will be helpful to more comprehensively understand the immune mechanism of teleost against C. irritans infection, and provide a theoretical basis for the prevention and treatment of Cryptosporidiosis.


Asunto(s)
Infecciones por Cilióforos , Cilióforos , Enfermedades de los Peces , Hymenostomatida , Perciformes , Animales , Cilióforos/fisiología , Proteínas de Peces/genética , Perfilación de la Expresión Génica/veterinaria
15.
Chem Rev ; 122(23): 16911-16982, 2022 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-36347015

RESUMEN

Nucleation and growth are critical steps in crystallization, which plays an important role in determining crystal structure, size, morphology, and purity. Therefore, understanding the mechanisms of nucleation and growth is crucial to realize the controllable fabrication of crystalline products with desired and reproducible properties. Based on classical models, the initial crystal nucleus is formed by the spontaneous aggregation of ions, atoms, or molecules, and crystal growth is dependent on the monomer's diffusion and the surface reaction. Recently, numerous in situ investigations on crystallization dynamics have uncovered the existence of nonclassical mechanisms. This review provides a summary and highlights the in situ studies of crystal nucleation and growth, with a particular emphasis on the state-of-the-art research progress since the year 2016, and includes technological advances, atomic-scale observations, substrate- and temperature-dependent nucleation and growth, and the progress achieved in the various materials: metals, alloys, metallic compounds, colloids, and proteins. Finally, the forthcoming opportunities and challenges in this fascinating field are discussed.


Asunto(s)
Coloides , Cristalización , Cinética , Coloides/química , Difusión , Temperatura
16.
J Fluoresc ; 34(1): 179-190, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37166611

RESUMEN

Simple and sensitive detection of cardiac biomarkers is of great significance for early diagnosis and prevention of acute myocardial infarction (AMI). Here, a ratiometric fluorescent nanohybrids probe (AuNCs-QDs) was synthesized through the coupling of bovine serum albumin-functionalized gold nanoclusters (AuNCs) with CdSe/ZnS quantum dots (QDs) to realize simple and sensitive detection of cardiac biomarker myoglobin (Mb). The AuNCs-QDs probe shows pink fluorescence under UV light, with two emission peaks at 468 nm and 630 nm belonging to QDs and AuNCs, respectively. Importantly, the presence of Mb caused fluorescence quenching of the blue-emitting QDs, thereby inhibiting the fluorescence resonance energy transfer (FRET) process between QDs and AuNCs, and reducing the fluorescence intensity ratio (F468/F630) of AuNCs-QDs probe effectively. As the concentration of Mb increases, the ratiometric fluorescent probe also exhibits a visible fluorescence color change. The detection limit was as low as 4.99 µg/mL, and the response of the probe to Mb showed a good linear relationship up to 0.52 mg/mL. Moreover, the probe has excellent specificity for Mb. Besides, the AuNCs-QDs has been applied to detect Mb of urine samples. More importantly, we also developed an AuNCs-QDs probe modified smartphone-aided paper-based strip for on-site monitoring of Mb. As far as we know, this is the first report of a smartphone-aided paper-based strip for on-site quick monitoring of Mb, which provides a useful approach for AMI biomarker monitoring and may can be extended to other medical diagnostics.


Asunto(s)
Nanopartículas del Metal , Puntos Cuánticos , Mioglobina , Teléfono Inteligente , Espectrometría de Fluorescencia , Colorantes Fluorescentes , Oro , Biomarcadores
17.
Mol Biol Rep ; 51(1): 83, 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38183491

RESUMEN

Inflammation is a complex biological response triggered when an organism encounters internal or external stimuli. These triggers activate various signaling pathways, leading to the release of numerous inflammatory mediators aimed at the affected tissue. Ensuring precision and avoiding the excessive activation, the inflammatory process is subject to tight regulation. Histone deacetylase 3 (HDAC3), a member of class I HDACs family, stands out for its significant role in modulating various inflammatory signaling, including Nuclear Factor kappa B (NF-κB) signaling, Mitogen-activated protein kinase (MAPK) signaling and Janus kinase/signal transduction and activator of transcription (JAK-STAT) signaling. In this review, we illuminate the intricate molecular mechanisms of HDAC3 across these inflammatory pathways. We emphasize its importance in orchestrating a balanced inflammatory response and highlight its promising potential as a therapeutic target.


Asunto(s)
Histona Desacetilasas , Inflamación , Humanos , Histona Desacetilasas/genética , Mediadores de Inflamación , Quinasas Janus
18.
J Phys Chem A ; 128(27): 5386-5397, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38951489

RESUMEN

We provide an approach to sample rare events during classical ab initio molecular dynamics and quantum wavepacket dynamics. For classical AIMD, a set of fictitious degrees of freedom are introduced that may harmonically interact with the electronic and nuclear degrees of freedom to steer the dynamics in a conservative fashion toward energetically forbidden regions. A similar approach when introduced for quantum wavepacket dynamics has the effect of biasing the trajectory of the wavepacket centroid toward the regions of the potential surface that are difficult to sample. The approach is demonstrated for a phenol-amine system, which is a prototypical problem for condensed phase-proton transfer, and for model potentials undergoing wavepacket dynamics. In all cases, the approach yields trajectories that conserve energy while sampling rare events.

19.
Environ Res ; 251(Pt 2): 118688, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38493855

RESUMEN

The widespread usage of quaternary ammonium compounds (QACs) as disinfectants during the COVID-19 pandemic poses significant environmental risks, such as toxicity to organisms and the emergence of superbugs. In this study, different inorganic salts (NaCl, KCl, CaCl2, MgCl2) were used to induce endophytes LSE01 isolated from hyperaccumulating plants. After five generations of cultivation under 80 g/L NaCl, the minimum inhibitory concentration (MIC) of LSE01 to QACs increased by about 3-fold, while its degradation extent increased from 8% to 84% for C12BDMA-Cl and 5%-89% for C14BDMA-Cl. Transmission electron microscopy (TEM) and three-dimensional fluorescence spectra indicated that the cells induced by high concentration of salt caused plasmolysis and secreted more bound extracellular polymeric substances (B-EPS); these changes are likely to be an important reason for the observed increased resistance and enhanced degradation extent of LSE01 to QACs. Our findings suggest that salt-induction could be an effective way to enhance the resistance and removal of toxic organic pollutants by functional microorganisms.


Asunto(s)
Endófitos , Compuestos de Amonio Cuaternario , Salinidad , Compuestos de Amonio Cuaternario/farmacología , Pruebas de Sensibilidad Microbiana , Bacterias/efectos de los fármacos , Biodegradación Ambiental
20.
Anesth Analg ; 138(3): 589-597, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38100389

RESUMEN

BACKGROUND: The goal of this study was to investigate the efficacy of neostigmine on postoperative cognitive dysfunction (POCD) and determine its effect on systematic markers of oxidative stress in older patients. METHODS: This double-blind placebo-controlled trial enrolled 118 elderly patients (≥65 years) undergoing noncardiac surgeries who were allocated to a neostigmine treatment group (0.04 mg/kg) or a placebo control group (normal saline) postoperatively. POCD was diagnosed if the Z -scores for the mini-mental state examination and the Montreal Cognitive Assessment were both ≤-1.96. Postoperative serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), and brain-derived neurotrophic factor (BDNF) were also compared. Multivariable regression analysis with dose adjustment of atropine was used to demonstrate the influence of neostigmine on the incidence of POCD. RESULTS: Patients receiving neostigmine had a significantly reduced incidence of POCD compared to patients who were treated with placebo on the first day after surgery (-22%, 95% confidence interval [CI], -37 to -7), but not on the third (8%, 95% CI, -4 to 20) or seventh day after surgery (3%, 95% CI, -7 to 13). Postoperative plasma MDA levels were significantly lower ( P = .016), but SOD and BDNF levels were increased ( P = .036 and .013, respectively) in the neostigmine group compared to the control group on the first day after surgery. CONCLUSIONS: Neostigmine reduced POCD on the first day after noncardiac surgery in older patients. Neostigmine treatment inhibited oxidative stress and increased serum BDNF levels. There was no significant influence of neostigmine on POCD on the third or seventh day after surgery. The clinical influence of neostigmine on POCD should be further investigated.


Asunto(s)
Disfunción Cognitiva , Complicaciones Cognitivas Postoperatorias , Anciano , Humanos , Factor Neurotrófico Derivado del Encéfalo , Disfunción Cognitiva/complicaciones , Neostigmina/efectos adversos , Complicaciones Cognitivas Postoperatorias/inducido químicamente , Complicaciones Cognitivas Postoperatorias/diagnóstico , Complicaciones Cognitivas Postoperatorias/epidemiología , Complicaciones Posoperatorias/inducido químicamente , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Superóxido Dismutasa , Método Doble Ciego
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