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1.
Science ; 385(6708): adl2992, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39088624

RESUMEN

Late-onset Alzheimer's disease (LOAD) is the most common form of Alzheimer's disease (AD). However, modeling sporadic LOAD that endogenously captures hallmark neuronal pathologies such as amyloid-ß (Aß) deposition, tau tangles, and neuronal loss remains an unmet need. We demonstrate that neurons generated by microRNA (miRNA)-based direct reprogramming of fibroblasts from individuals affected by autosomal dominant AD (ADAD) and LOAD in a three-dimensional environment effectively recapitulate key neuropathological features of AD. Reprogrammed LOAD neurons exhibit Aß-dependent neurodegeneration, and treatment with ß- or γ-secretase inhibitors before (but not subsequent to) Aß deposit formation mitigated neuronal death. Moreover inhibiting age-associated retrotransposable elements in LOAD neurons reduced both Aß deposition and neurodegeneration. Our study underscores the efficacy of modeling late-onset neuropathology of LOAD through high-efficiency miRNA-based neuronal reprogramming.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Reprogramación Celular , Fibroblastos , MicroARNs , Neuronas , Esferoides Celulares , Humanos , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Secretasas de la Proteína Precursora del Amiloide/genética , Reprogramación Celular/genética , Fibroblastos/metabolismo , Fibroblastos/patología , MicroARNs/genética , MicroARNs/metabolismo , Neuronas/metabolismo , Neuronas/patología
2.
J Am Chem Soc ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110419

RESUMEN

(Z)-1,2-Disubstituted, trisubstituted, and tetrasubstituted alkenes are not only important units in medicinal chemistry, natural product synthesis, and material science but also useful intermediates in organic synthesis. Development of catalytic stereoselective transformations to access multisubstituted alkenes with various substitution patterns from easily accessible modular starting materials and readily available catalysts is a crucial goal in the field of catalysis. Water is an ideal hydrogen source for catalytic transfer hydrogenation despite of the high difficulty to activate water. Here, we report a cobalt-catalyzed protocol for regio- and stereoselective transfer semihydrogenation of 1,3-dienes to construct a broad scope of (Z)-1,2-disubstituted, (Z)-, (E)-trisubstituted, and tetrasubstituted alkenes in high stereoselectivity with H2O as the hydrogen source. Mechanistic studies revealed that the reactions proceeded through a unique Co(I)/Co(III) cycle and involved a 1,4-cobalt shift process, which is an unprecedented reaction pathway, providing a new platform for modular synthesis of multisubstituted alkenes as well as opportunities for designing novel reaction modes and pushing forward the advancement in organocobalt chemistry.

3.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2947-2952, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39041154

RESUMEN

This paper aimed to study the chemical constituents from Clitocybe clavipes. Silica gel, ODS, Sephadex LH-20, and semi-p reparative HPLC were employed to separate the ethanol extract of C. clavipes. Six compounds were identified by ~1H-NMR, ~(13)CNMR,and ESI-MS as clavilactone L(1), clavilactone A(2), clavilactone B(3), clavilactone E(4), clavilactone H(5), and clav ilactone I(6). Among them, compound 1 was a new meroterpenoid with a 10-membered carbocycle connected to a hydroquinone. Theantitumor activities of compounds 1-6 were determined by the methyl thiazolyl tetrazolium(MTT) ass ay. The results showed that compounds 1-6 exerted inhibitory effects on the proliferation of human gastric cancer cells(MGC-803),human non-small cell lung cancer cells(A549), and cervical cancer cells(HeLa). Compound 1 exhibited significant inhibitory activity against MGC-803 cells, with the half maximal inhibitory concentration(IC_(50)) of 11. 76 µmol·L~(-1).


Asunto(s)
Proliferación Celular , Humanos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Estructura Molecular , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química
4.
J Chem Phys ; 161(1)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38958161

RESUMEN

The evaporation-induced deposition pattern of the linear diblock copolymer solution has attracted attention in recent years. Given its critical applications, we study deposition patterns of the linear diblock copolymer solution nanodroplet on a solid surface (the wall) by molecular dynamics simulations. This study focuses on the influence of the nonbonded interaction strength, including the interaction between the wall and polymer blocks (ɛAW and ɛBW), the interaction between the solvent and the wall (ɛSW), and the interaction between polymer blocks (ɛAB). Conditions leading to diverse deposition patterns are explored, including the coffee-ring and the volcano-like structures. The formation of the coffee-ring structure is attributed to receding interfaces, the heterogeneity inside the droplet, and the self-assembly of polymer chains. This study contributes to the establishment of guidelines for designing deposition patterns of the linear diblock copolymer solution nanodroplet, which facilitates practical applications such as inkjet printing.

5.
Nano Lett ; 24(31): 9675-9682, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39058271

RESUMEN

Feeding silkworms with functional materials as additives to produce naturally modified silk is a facile, diverse, controllable, and environmentally friendly method with a low cost of time and investment. Among various additives, carbon dots (CDs) show unique advantages due to their excellent biocompatibility and fluorescence stability. Here, a new type of green fluorescent carbon dots (G-CDs) is synthesized with a high oil-water partition ratio of 147, a low isoelectric point of 5.16, an absolute quantum yield of 71%, and critically controlled surface states. After feeding with G-CDs, the silkworms weave light yellow cocoons whose green fluorescence is visible to the naked eye under UV light. The luminous silk is sewn onto the cloth to create striking patterns with beautiful fluorescence. Such G-CDs have no adverse effect on the survival rate and the life cycle of silkworms and enable their whole bodies to glow under UV light. Based on the strong fluorescence, chemical stability, and biological safety, G-CDs are found in the digestive tracts, silk glands, feces, cocoons, and even moth bodies. G-CDs accumulate in the posterior silk glands where fibroin protein is secreted, indicating its stronger combination with fibroin than sericin, which meets the requirements for practical applications.


Asunto(s)
Bombyx , Carbono , Puntos Cuánticos , Seda , Animales , Seda/química , Carbono/química , Puntos Cuánticos/química , Fibroínas/química , Rayos Ultravioleta , Fluorescencia , Colorantes Fluorescentes/química , Propiedades de Superficie
6.
Talanta ; 278: 126533, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39029327

RESUMEN

Compact and user-friendly nucleic acid biosensors play a crucial role in advancing infectious disease research, particularly for coronavirus (COVID-19). While nanophotonic metasurface sensors hold promise for high-performance sensing, they face challenges due to their complexity and bulky readout instruments. In this study, we propose a gradient nanoplasmonic imaging (GNI) metasurface that incorporates the concept of an optical potential well, enabling label-free single-step detection of SARS-CoV-2 sequences. The metasurface sensor consists of nanopillars with continuous variations, forming an optical potential well that results in a centimeter-scale dark ring. This dynamic well exhibits high sensitivity to refractive index changes, recorded by a CCD. To further enhance the visualized sensing performance, plasmonic coupling of gold nanoparticles with the gold nanostructure is employed. Our metasurface-based biosensor achieves rapid single-step detection of SARS-CoV-2 sequences, with a low detection limit of 77.2 pM and a detection range of 0.1-100 nM. This biosensor not only demonstrates exceptional reproducibility and outstanding detection performance, but also maintains remarkable specificity in differentiating SARS-CoV-2 from other diseases with similar symptoms. This simple and spectrometer-free refractometric sensing scheme enables the construction of a compact and cost-efficient prototype. Our imaging-based metasurface biosensing strategy demonstrates valuable merits for rapid, sensitive, and quantitative detection, showcasing its potential as a valuable on-site nucleic acid diagnostic tool.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Oro , Nanopartículas del Metal , SARS-CoV-2 , SARS-CoV-2/aislamiento & purificación , Oro/química , Técnicas Biosensibles/métodos , Nanopartículas del Metal/química , COVID-19/diagnóstico , COVID-19/virología , Humanos , Límite de Detección , Nanotecnología/métodos
7.
World J Gastrointest Surg ; 16(6): 1582-1591, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983354

RESUMEN

BACKGROUND: Intraoperative persistent hypotension (IPH) during pancreaticoduodenectomy (PD) is linked to adverse postoperative outcomes, yet its risk factors remain unclear. AIM: To clarify the risk factors associated with IPH during PD, ensuring patient safety in the perioperative period. METHODS: A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD. These factors included age, gender, body mass index, American Society of Anesthesiologists classification, comorbidities, medication history, operation duration, fluid balance, blood loss, urine output, and blood gas parameters. IPH was defined as sustained mean arterial pressure < 65 mmHg, requiring prolonged deoxyepinephrine infusion for > 30 min despite additional deoxyepinephrine and fluid treatments. RESULTS: Among 1596 PD patients, 661 (41.42%) experienced IPH. Multivariate logistic regression identified key risk factors: increased age [odds ratio (OR): 1.20 per decade, 95% confidence interval (CI): 1.08-1.33] (P < 0.001), longer surgery duration (OR: 1.15 per additional hour, 95%CI: 1.05-1.26) (P < 0.01), and greater blood loss (OR: 1.18 per 250-mL increment, 95%CI: 1.06-1.32) (P < 0.01). A novel finding was the association of arterial blood Ca2+ < 1.05 mmol/L with IPH (OR: 2.03, 95%CI: 1.65-2.50) (P < 0.001). CONCLUSION: IPH during PD is independently associated with older age, prolonged surgery, increased blood loss, and lower plasma Ca2+.

8.
Bioresour Technol ; 406: 130955, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38871228

RESUMEN

Thermophilic semi-continuous composting (TSC) is effective for kitchen waste (KW) treatment, but large amounts of NH3-rich odorous gas are generated. This study proposes a TSC-biofiltration (BF) two-stage process. Compost from the front-end TSC was used as the packing material in the BF to remove NH3 from the exhaust gas. The BF process was effective in removing up to 83.7 % of NH3, and the NH3 content was reduced to < 8 ppm. Seven days of BF improved the quality of the product from TSC by enhancing the germination index to 134.6 %, 36.5 % higher than that in the aerated-only group. Microbial community analysis revealed rapid proliferation and eventual dominance in the BF of members related to compost maturation and the nitrogen cycle from Actinobacteria, Proteobacteria, Chloroflexi, and Bacteroidetes. The results suggest that the TSC-BF two-stage process is effective in reducing NH3 emissions from TSC and improving compost quality.


Asunto(s)
Amoníaco , Compostaje , Fertilizantes , Compostaje/métodos , Filtración/métodos , Eliminación de Residuos/métodos , Temperatura , Suelo/química , Bacterias/metabolismo
9.
Small ; : e2402842, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38923165

RESUMEN

The nacre-inspired multi-nanolayer structure offers a unique combination of advanced mechanical properties, such as strength and crack tolerance, making them highly versatile for various applications. Nevertheless, a significant challenge lies in the current fabrication methods, which is difficult to create a scalable manufacturing process with precise control of hierarchical structure. In this work, a novel strategy is presented to regulate nacre-like multi-nanolayer films with the balance mechanical properties of stiffness and toughness. By utilizing a co-continuous phase structure and an extensional stress field, the hierarchical nanolayers is successfully constructed with tunable sizes using a scalable processing technique. This strategic modification allows the robust phase to function as nacre-like platelets, while the soft phase acts as a ductile connection layer, resulting in exceptional comprehensive properties. The nanolayer-structured films demonstrate excellent isotropic properties, including a tensile strength of 113.5 MPa in the machine direction and 106.3 MPa in a transverse direction. More interestingly, these films unprecedentedly exhibit a remarkable puncture resistance at the same time, up to 324.8 N mm-1, surpassing the performance of other biodegradable films. The scalable fabrication strategy holds significant promise in designing advanced bioinspired materials for diverse applications.

10.
Thorac Cancer ; 15(19): 1502-1512, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38798202

RESUMEN

BACKGROUND: Malignant mesothelioma (MM) is an exceedingly rare tumor with poor prognosis due to the limited availability of effective treatment. Immunotherapy has emerged as a novel treatment approach for MM, but less than 40% of the patients benefit from it. Thus, it is necessary to identify accurate and effective biomarkers that can predict the overall survival (OS) and immunotherapy efficacy for MM. METHODS: DNA sequencing was used to identify the genomic landscape based on the data from 86 Chinese patients. T cell receptor (TCR) sequencing was used to characterize MM TCR repertoires of 28 patients between October 2016 and April 2023. RESULTS: Patients with TP53, NF2, or CDKN2A variants at the genomic level, as well as those exhibiting lower Shannon index (<6.637), lower evenness (<0.028), or higher clonality (≥0.194) according to baseline tumor tissue TCR indexes, demonstrated poorer OS. Furthermore, patients with TP53, CDKN2A, or CDKN2B variants and those with a lower evenness (<0.030) in baseline tumor tissue showed worse immunotherapy efficacy. The present study is the first to identify five special TCR Vß-Jß rearrangements associated with MM immunotherapy efficacy. CONCLUSIONS: The present study reported the largest-scale genomic landscape and TCR repertoire of MM in Chinese patients and identified genomic and TCR biomarkers for the prognosis and immunotherapy efficacy in MM. The study results might provide new insights for prospective MM trials using specific genes, TCR indexes, and TCR clones as biomarkers and offer a reference for future antitumor drugs based on TCR-specific clones.


Asunto(s)
Biomarcadores de Tumor , Mesotelioma Maligno , Humanos , Mesotelioma Maligno/genética , Masculino , Femenino , Biomarcadores de Tumor/genética , Persona de Mediana Edad , Anciano , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Pronóstico , Genómica/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Adulto , Mesotelioma/genética , Mesotelioma/mortalidad , Mesotelioma/patología , Inmunoterapia/métodos , Linfocitos T/metabolismo , Linfocitos T/inmunología
11.
Angew Chem Int Ed Engl ; 63(33): e202405290, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38818654

RESUMEN

Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from a newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for cobalt catalysis and a general approach that enable rapid construction of highly diversified enantioenriched allylic alcohols containing a 1,1-, 1,2-disubstituted and trisubstituted alkene as well as axial stereogenicity in up to 99 % yield and 99 : 1 er without the need of preformation of alkenyl-metal reagents. DFT calculations revealed the origin of enantioselectivity.

12.
BMC Microbiol ; 24(1): 158, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720268

RESUMEN

BACKGROUND: The production of succinic acid (SA) from biomass has attracted worldwide interest. Saccharomyces cerevisiae is preferred for SA production due to its strong tolerance to low pH conditions, ease of genetic manipulation, and extensive application in industrial processes. However, when compared with bacterial producers, the SA titers and productivities achieved by engineered S. cerevisiae strains were relatively low. To develop efficient SA-producing strains, it's necessary to clearly understand how S. cerevisiae cells respond to SA. RESULTS: In this study, we cultivated five S. cerevisiae strains with different genetic backgrounds under different concentrations of SA. Among them, KF7 and NBRC1958 demonstrated high tolerance to SA, whereas NBRC2018 displayed the least tolerance. Therefore, these three strains were chosen to study how S. cerevisiae responds to SA. Under a concentration of 20 g/L SA, only a few differentially expressed genes were observed in three strains. At the higher concentration of 60 g/L SA, the response mechanisms of the three strains diverged notably. For KF7, genes involved in the glyoxylate cycle were significantly downregulated, whereas genes involved in gluconeogenesis, the pentose phosphate pathway, protein folding, and meiosis were significantly upregulated. For NBRC1958, genes related to the biosynthesis of vitamin B6, thiamin, and purine were significantly downregulated, whereas genes related to protein folding, toxin efflux, and cell wall remodeling were significantly upregulated. For NBRC2018, there was a significant upregulation of genes connected to the pentose phosphate pathway, gluconeogenesis, fatty acid utilization, and protein folding, except for the small heat shock protein gene HSP26. Overexpression of HSP26 and HSP42 notably enhanced the cell growth of NBRC1958 both in the presence and absence of SA. CONCLUSIONS: The inherent activities of small heat shock proteins, the levels of acetyl-CoA and the strains' potential capacity to consume SA all seem to affect the responses and tolerances of S. cerevisiae strains to SA. These factors should be taken into consideration when choosing host strains for SA production. This study provides a theoretical basis and identifies potential host strains for the development of robust and efficient SA-producing strains.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Saccharomyces cerevisiae , Ácido Succínico , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ácido Succínico/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fermentación
13.
Biotechnol Adv ; 73: 108372, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38714276

RESUMEN

Anaerobic digestion (AD) is an effective and applicable technology for treating organic wastes to recover bioenergy, but it is limited by various drawbacks, such as long start-up time for establishing a stable process, the toxicity of accumulated volatile fatty acids and ammonia nitrogen to methanogens resulting in extremely low biogas productivities, and a large amount of impurities in biogas for upgrading thereafter with high cost. Microbial electrolysis cell (MEC) is a device developed for electrosynthesis from organic wastes by electroactive microorganisms, but MEC alone is not practical for production at large scales. When AD is integrated with MEC, not only can biogas production be enhanced substantially, but also upgrading of the biogas product performed in situ. In this critical review, the state-of-the-art progress in developing AD-MEC systems is commented, and fundamentals underlying methanogenesis and bioelectrochemical reactions, technological innovations with electrode materials and configurations, designs and applications of AD-MEC systems, and strategies for their enhancement, such as driving the MEC device by electricity that is generated by burning the biogas to improve their energy efficiencies, are specifically addressed. Moreover, perspectives and challenges for the scale up of AD-MEC systems are highlighted for in-depth studies in the future to further improve their performance.


Asunto(s)
Fuentes de Energía Bioeléctrica , Biocombustibles , Electrólisis , Anaerobiosis , Fuentes de Energía Bioeléctrica/microbiología , Reactores Biológicos , Metano/metabolismo
14.
J Nat Med ; 78(3): 702-708, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38662303

RESUMEN

Two new sesterterpenoids, atractylodes japonica terpenoid acid I (1) and atractylodes japonica terpenoid aldehyde I (2), were isolated from the rhizomes of Atractylodes japonica Koidz. ex Kitam together with ten known compounds (3-12). Their structures were elucidated on the basis of comprehensive spectroscopic analysis (1D/2D NMR, HRESIMS and IR). In addition, all of these isolated compounds were evaluated for their cytotoxic activities against human gastric cancer cell MGC-803 and human hepatocellular cancer cell HepG-2. Most of them exhibited moderate to weak inhibitory effects with IC50 values in the range of 25.15-88.85 µM except for 9-12.


Asunto(s)
Atractylodes , Rizoma , Sesterterpenos , Atractylodes/química , Humanos , Estructura Molecular , Línea Celular Tumoral , Sesterterpenos/química , Sesterterpenos/farmacología , Sesterterpenos/aislamiento & purificación , Rizoma/química , Células Hep G2 , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Extractos Vegetales/química , Extractos Vegetales/farmacología
15.
Int Immunopharmacol ; 133: 112053, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38615380

RESUMEN

Although PD-1 inhibitors have revolutionized the treatment paradigm of non-small cell lung cancer (NSCLC), their efficacy in treating NSCLC has remained unsatisfactory. Targeting cancer-associated fibroblasts (CAFs) is a potential approach for improving the immunotherapy response. Multitarget antiangiogenic tyrosine kinase receptor inhibitors (TKIs) can enhance the efficacy of PD-1 inhibitors in NSCLC patients. However, the effects and mechanisms of antiangiogenic TKIs on CAFs have not been elucidated. In this study, we first compared anlotinib with other antiangiogenic TKIs and confirmed the superior efficacy of anlotinib. Furthermore, we established NSCLC-associated CAF models and found that anlotinib impaired CAF viability and migration capacity and contributed to CAF apoptosis and cell cycle arrest in the G2/M phase. Moreover, anlotinib treatment attenuated the capacity of CAFs to recruit lung cancer cells and macrophages. Experiments in animal models suggested that anlotinib could enhance the efficacy of anti-PD1 therapy in NSCLC and affect CAF proliferation and apoptosis. Anlotinib increased the abundance of tumor-infiltrating CD8 + T cells, and PD-1 inhibitor-induced cytotoxicity to tumor cells was achieved through the transformation of the tumor microenvironment (TME) caused by anlotinib, which may partly explain the synergistic antitumor effect of anlotinib and PD-1 inhibitors. Mechanistically, anlotinib affects CAF apoptosis and cell viability at least in part by inhibiting the AKT pathway. In conclusion, our study suggested that anlotinib could regulate the TME, inhibit the AKT pathway and promote CAF apoptosis, providing new insights into the antitumor effect of anlotinib and improving the efficacy of immunotherapy.


Asunto(s)
Adenocarcinoma del Pulmón , Apoptosis , Indoles , Neoplasias Pulmonares , Receptor de Muerte Celular Programada 1 , Proteínas Proto-Oncogénicas c-akt , Quinolinas , Quinolinas/farmacología , Quinolinas/uso terapéutico , Animales , Indoles/farmacología , Indoles/uso terapéutico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/inmunología , Apoptosis/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Ratones , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/patología , Línea Celular Tumoral , Transducción de Señal/efectos de los fármacos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Ratones Endogámicos BALB C , Sinergismo Farmacológico
16.
Yi Chuan ; 46(4): 279-289, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38632091

RESUMEN

H2A.Z, one of the most well-known variants of histone H2A, has been extensively investigated on its dual roles in gene transcription in recent years. In this review, we focus on the intricate involvement of H2A.Z in transcriptional regulation, including the assembly of distinct H2A.Z subtypes, post-translational modifications and genomic distributions. Emphasis is placed on the biological and pathophysiological implications, particularly in tumorigenesis and nervous system development. We summarize the dynamic regulatory mechanisms governing H2A.Z deposition or eviction on chromatin to provide insights for understanding the diversity of histone variants and promoting the search of new targets in concerned disease diagnosis and treatment.


Asunto(s)
Histonas , Nucleosomas , Histonas/metabolismo , Cromatina , Regulación de la Expresión Génica , Genoma
17.
Microsyst Nanoeng ; 10: 49, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38595945

RESUMEN

The high stretchability of two-dimensional (2D) materials has facilitated the possibility of using external strain to manipulate their properties. Hence, strain engineering has emerged as a promising technique for tailoring the performance of 2D materials by controlling the applied elastic strain field. Although various types of strain engineering methods have been proposed, deterministic and controllable generation of the strain in 2D materials remains a challenging task. Here, we report a nanoimprint-induced strain engineering (NISE) strategy for introducing controllable periodic strain profiles on 2D materials. A three-dimensional (3D) tunable strain is generated in a molybdenum disulfide (MoS2) sheet by pressing and conforming to the topography of an imprint mold. Different strain profiles generated in MoS2 are demonstrated and verified by Raman and photoluminescence (PL) spectroscopy. The strain modulation capability of NISE is investigated by changing the imprint pressure and the patterns of the imprint molds, which enables precise control of the strain magnitudes and distributions in MoS2. Furthermore, a finite element model is developed to simulate the NISE process and reveal the straining behavior of MoS2. This deterministic and effective strain engineering technique can be easily extended to other materials and is also compatible with common semiconductor fabrication processes; therefore, it provides prospects for advances in broad nanoelectronic and optoelectronic devices.

18.
J Chem Phys ; 160(14)2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38591682

RESUMEN

Designing homogeneous networks is considered one typical strategy for solving the problem of strength and toughness conflict of polymer network materials. Experimentalists have proposed the hypothesis of obtaining a structurally homogeneous hydrogel by crosslinking tetra-armed polymers, whose homogeneity was claimed to be verified by scattering characterization and other methods. Nevertheless, it is highly desirable to further evaluate this issue from other perspectives. In this study, a coarse-grained molecular dynamics simulation coupled with a stochastic reaction model is applied to reveal the topological structure of a polymer network synthesized by tetra-armed monomers as precursors. Two different scenarios, distinguished by whether internal cross-linking is allowed, are considered. We introduce the Dijkstra algorithm from graph theory to precisely characterize the network structure. The microscopic features of the network structure, e.g., loop size, dispersity, and size distribution, are obtained via the Dijkstra algorithm. By comparing the two reaction scenarios, Scenario II exhibits an overall more idealized structure. Our results demonstrate the feasibility of the Dijkstra algorithm for precisely characterizing the polymer network structure. We expect this work will provide a new insight for the evaluation and description of gel networks and further help to reveal the dynamic process of network formation.

19.
Molecules ; 29(4)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38398616

RESUMEN

Phytopathogenic fungi cause plant diseases and economic losses in agriculture. To efficiently control plant pathogen infections, a total of 19 spirotryprostatin A derivatives and 26 spirooxindole derivatives were designed, synthesized, and tested for their antifungal activity against ten plant pathogens. Additionally, the intermediates of spirooxindole derivatives were investigated, including proposing a mechanism for diastereoselectivity and performing amplification experiments. The bioassay results demonstrated that spirotryprostatin A derivatives possess good and broad-spectrum antifungal activities. Compound 4d exhibited excellent antifungal activity in vitro, equal to or higher than the positive control ketoconazole, against Helminthosporium maydis, Trichothecium roseum, Botrytis cinerea, Colletotrichum gloeosporioides, Fusarium graminearum, Alternaria brassicae, Alternaria alternate, and Fusarium solan (MICs: 8-32 µg/mL). Compound 4k also displayed remarkable antifungal activity against eight other phytopathogenic fungi, including Fusarium oxysporium f. sp. niveum and Mycosphaerella melonis (MICs: 8-32 µg/mL). The preliminary structure-activity relationships (SARs) were further discussed. Moreover, molecular docking studies revealed that spirotryprostatin A derivatives anchored in the binding site of succinate dehydrogenase (SDH). Therefore, these compounds showed potential as natural compound-based chiral fungicides and hold promise as candidates for further enhancements in terms of structure and properties.


Asunto(s)
Antifúngicos , Benzopiranos , Fungicidas Industriales , Nitrilos , Oxindoles , Piperazinas , Compuestos de Espiro , Antifúngicos/química , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad , Fungicidas Industriales/farmacología
20.
Cardiovasc Diabetol ; 23(1): 51, 2024 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310324

RESUMEN

BACKGROUND: It has been confirmed that the ApoB/ApoA1 ratio is closely associated with the incidence of cardiometabolic diseases (CMD). However, due to uncontrolled confounding factors in observational studies, the causal relationship of this association remains unclear. METHODS: In this study, we extracted the ApoB/ApoA1 ratio and data on CMD and its associated risk factors from the largest European Genome-Wide Association Study. The purpose was to conduct Mendelian Randomization (MR) analysis. The causal relationship between the ApoB/ApoA1 ratio and CMD was evaluated using both univariable and multivariable MR analyses. Furthermore, bidirectional MR analysis was performed to estimate the causal relationship between the ApoB/ApoA1 ratio and risk factors for CMD. The final verification confirmed whether the ApoB/ApoA1 ratio exhibits a mediating effect in CMD and related risk factors. RESULTS: In terms of CMD, a noteworthy correlation was observed between the increase in the ApoB/ApoA1 ratio and various CMD, including ischemic heart disease, major adverse cardiovascular events, aortic aneurysm, cerebral ischemic disease and so on (all PFDR<0.05). Meanwhile, the ApoB/ApoA1 ratio was significantly associated with CMD risk factors, such as hemoglobin A1c, fasting insulin levels, waist-to-hip ratio, sedentary behavior, and various others, demonstrating a notable causal relationship (all PFDR<0.05). Additionally, the ApoB/ApoA1 ratio played a mediating role in CMD and relative risk factors. CONCLUSIONS: This MR study provides evidence supporting the significant causal relationship between the ApoB/ApoA1 ratio and CMD and its risk factors. Moreover, it demonstrates the mediating effect of the ApoB/ApoA1 ratio in CMD and its risk factors. These findings suggest that the ApoB/ApoA1 ratio may serve as a potential indicator for identifying the risk of developing CMD in participants.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Isquemia Miocárdica , Humanos , Estudio de Asociación del Genoma Completo , Biomarcadores , Factores de Riesgo
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