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1.
Nature ; 628(8008): 664-671, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38600377

RESUMEN

Bitter taste sensing is mediated by type 2 taste receptors (TAS2Rs (also known as T2Rs)), which represent a distinct class of G-protein-coupled receptors1. Among the 26 members of the TAS2Rs, TAS2R14 is highly expressed in extraoral tissues and mediates the responses to more than 100 structurally diverse tastants2-6, although the molecular mechanisms for recognizing diverse chemicals and initiating cellular signalling are still poorly understood. Here we report two cryo-electron microscopy structures for TAS2R14 complexed with Ggust (also known as gustducin) and Gi1. Both structures have an orthosteric binding pocket occupied by endogenous cholesterol as well as an intracellular allosteric site bound by the bitter tastant cmpd28.1, including a direct interaction with the α5 helix of Ggust and Gi1. Computational and biochemical studies validate both ligand interactions. Our functional analysis identified cholesterol as an orthosteric agonist and the bitter tastant cmpd28.1 as a positive allosteric modulator with direct agonist activity at TAS2R14. Moreover, the orthosteric pocket is connected to the allosteric site via an elongated cavity, which has a hydrophobic core rich in aromatic residues. Our findings provide insights into the ligand recognition of bitter taste receptors and suggest activities of TAS2R14 beyond bitter taste perception via intracellular allosteric tastants.


Asunto(s)
Colesterol , Espacio Intracelular , Receptores Acoplados a Proteínas G , Gusto , Humanos , Regulación Alostérica/efectos de los fármacos , Sitio Alostérico , Colesterol/química , Colesterol/metabolismo , Colesterol/farmacología , Microscopía por Crioelectrón , Interacciones Hidrofóbicas e Hidrofílicas , Espacio Intracelular/química , Espacio Intracelular/metabolismo , Ligandos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestructura , Reproducibilidad de los Resultados , Gusto/efectos de los fármacos , Gusto/fisiología , Transducina/química , Transducina/metabolismo , Transducina/ultraestructura
2.
Nature ; 621(7979): 610-619, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37557913

RESUMEN

The proper regulation of transcription is essential for maintaining genome integrity and executing other downstream cellular functions1,2. Here we identify a stable association between the genome-stability regulator sensor of single-stranded DNA (SOSS)3 and the transcription regulator Integrator-PP2A (INTAC)4-6. Through SSB1-mediated recognition of single-stranded DNA, SOSS-INTAC stimulates promoter-proximal termination of transcription and attenuates R-loops associated with paused RNA polymerase II to prevent R-loop-induced genome instability. SOSS-INTAC-dependent attenuation of R-loops is enhanced by the ability of SSB1 to form liquid-like condensates. Deletion of NABP2 (encoding SSB1) or introduction of cancer-associated mutations into its intrinsically disordered region leads to a pervasive accumulation of R-loops, highlighting a genome surveillance function of SOSS-INTAC that enables timely termination of transcription at promoters to constrain R-loop accumulation and ensure genome stability.


Asunto(s)
Inestabilidad Genómica , Regiones Promotoras Genéticas , Estructuras R-Loop , Terminación de la Transcripción Genética , Humanos , ADN de Cadena Simple/metabolismo , Inestabilidad Genómica/genética , Mutación , Estructuras R-Loop/genética , ARN Polimerasa II/metabolismo , Regiones Promotoras Genéticas/genética , Genoma Humano , Proteínas de Unión al ADN/metabolismo
3.
Nature ; 591(7849): 288-292, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33658715

RESUMEN

The evolutionarily conserved target of rapamycin (TOR) kinase acts as a master regulator that coordinates cell proliferation and growth by integrating nutrient, energy, hormone and stress signals in all eukaryotes1,2. Research has focused mainly on TOR-regulated translation, but how TOR orchestrates the global transcriptional network remains unclear. Here we identify ethylene-insensitive protein 2 (EIN2), a central integrator3-5 that shuttles between the cytoplasm and the nucleus, as a direct substrate of TOR in Arabidopsis thaliana. Glucose-activated TOR kinase directly phosphorylates EIN2 to prevent its nuclear localization. Notably, the rapid global transcriptional reprogramming that is directed by glucose-TOR signalling is largely compromised in the ein2-5 mutant, and EIN2 negatively regulates the expression of a wide range of target genes of glucose-activated TOR that are involved in DNA replication, cell wall and lipid synthesis and various secondary metabolic pathways. Chemical, cellular and genetic analyses reveal that cell elongation and proliferation processes that are controlled by the glucose-TOR-EIN2 axis are decoupled from canonical ethylene-CTR1-EIN2 signalling, and mediated by different phosphorylation sites. Our findings reveal a molecular mechanism by which a central signalling hub is shared but differentially modulated by diverse signalling pathways using distinct phosphorylation codes that can be specified by upstream protein kinases.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Desarrollo de la Planta , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Arabidopsis/citología , Arabidopsis/genética , Dominio Catalítico , Proteínas de Unión al ADN/metabolismo , Etilenos/metabolismo , Glucosa/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Meristema/metabolismo , Fosforilación , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Quinasas/metabolismo , Especificidad por Sustrato , Factores de Transcripción/metabolismo , Transcriptoma
4.
Mol Cell ; 69(1): 100-112.e6, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29290610

RESUMEN

As sessile organisms, plants must adapt to variations in the environment. Environmental stress triggers various responses, including growth inhibition, mediated by the plant hormone abscisic acid (ABA). The mechanisms that integrate stress responses with growth are poorly understood. Here, we discovered that the Target of Rapamycin (TOR) kinase phosphorylates PYL ABA receptors at a conserved serine residue to prevent activation of the stress response in unstressed plants. This phosphorylation disrupts PYL association with ABA and with PP2C phosphatase effectors, leading to inactivation of SnRK2 kinases. Under stress, ABA-activated SnRK2s phosphorylate Raptor, a component of the TOR complex, triggering TOR complex dissociation and inhibition. Thus, TOR signaling represses ABA signaling and stress responses in unstressed conditions, whereas ABA signaling represses TOR signaling and growth during times of stress. Plants utilize this conserved phospho-regulatory feedback mechanism to optimize the balance of growth and stress responses.


Asunto(s)
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Receptores de Superficie Celular/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Proteína Reguladora Asociada a mTOR/metabolismo , Transducción de Señal , Estrés Fisiológico
5.
PLoS Pathog ; 19(1): e1011128, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36689483

RESUMEN

Coronavirus disease 2019 is a respiratory infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Evidence on the pathogenesis of SARS-CoV-2 is accumulating rapidly. In addition to structural proteins such as Spike and Envelope, the functional roles of non-structural and accessory proteins in regulating viral life cycle and host immune responses remain to be understood. Here, we show that open reading frame 8 (ORF8) acts as messenger for inter-cellular communication between alveolar epithelial cells and macrophages during SARS-CoV-2 infection. Mechanistically, ORF8 is a secretory protein that can be secreted by infected epithelial cells via both conventional and unconventional secretory pathways. Conventionally secreted ORF8 is glycosylated and loses the ability to recognize interleukin 17 receptor A of macrophages, possibly due to the steric hindrance imposed by N-glycosylation at Asn78. However, unconventionally secreted ORF8 does not undergo glycosylation without experiencing the ER-Golgi trafficking, thereby activating the downstream NF-κB signaling pathway and facilitating a burst of cytokine release. Furthermore, we show that ORF8 deletion in SARS-CoV-2 attenuates inflammation and yields less lung lesions in hamsters. Our data collectively highlights a role of ORF8 protein in the development of cytokine storms during SARS-CoV-2 infection.


Asunto(s)
COVID-19 , Síndrome de Liberación de Citoquinas , SARS-CoV-2 , Proteínas Virales , Humanos , COVID-19/patología , Síndrome de Liberación de Citoquinas/patología , Inflamación , Sistemas de Lectura Abierta , SARS-CoV-2/fisiología , Proteínas Virales/metabolismo
7.
Mol Ther ; 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38796700

RESUMEN

Prader-Willi syndrome (PWS) is the prototypic genomic disorder resulting from deficiency of paternally expressed genes in the human chromosome 15q11-q13 region. The unique molecular mechanism involving epigenetic modifications renders PWS as the most attractive candidate to explore a proof-of-concept of epigenetic therapy in humans. The premise is that epigenetic modulations could reactivate the repressed PWS candidate genes from the maternal chromosome and offer therapeutic benefit. Our prior study identifies an EHMT2/G9a inhibitor, UNC0642, that reactivates the expression of PWS genes via reduction of H3K9me2. However, low brain permeability and poor oral bioavailability of UNC0642 preclude its advancement into translational studies in humans. In this study, a newly developed inhibitor, MS152, modified from the structure of UNC0642, has better brain penetration and greater potency and selectivity against EHMT2/G9a. MS152 reactivated maternally silenced PWS genes in PWS patient fibroblasts and in brain and liver tissues of PWS mouse models. Importantly, the molecular efficacy of oral administration is comparable with the intraperitoneal route. MS152 treatment in newborns ameliorates the perinatal lethality and poor growth, maintaining reactivation in a PWS mouse model at postnatal 90 days. Our findings provide strong support for MS152 as a first-in-class inhibitor to advance the epigenetic therapy of PWS in humans.

8.
J Infect Dis ; 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38366561

RESUMEN

BACKGROUND: Lysins (cell wall hydrolases) targeting Gram-negative organisms require engineering to permeabilize the outer membrane and access subjacent peptidoglycan to facilitate killing. In the current study, the potential clinical utility for engineered lysin, CF-370, was examined in vitro and in vivo against Gram-negative pathogens important in human infections. METHODS: MICs and bactericidal activity were determined using standard methods. An in vivo proof-of-concept efficacy study was conducted using a rabbit acute pneumonia model caused by Pseudomonas aeruginosa. RESULTS: CF-370 exhibited potent antimicrobial activity, with MIC50/90 values (in µg/mL) for: P. aeruginosa, 1/2; Acinetobacter baumannii, 1/1; Escherichia coli, 0.25/1; Klebsiella pneumoniae, 2/4; Enterobacter cloacae 1/4; and Stenotrophomonas maltophilia 2/8. CF-370 furthermore demonstrated: i) bactericidal activity; (ii) activity in serum; iii) a low propensity for resistance; iv) anti-biofilm activity; and v) synergy with antibiotics. In the pneumonia model, CF-370 alone decreased bacterial densities in lungs, kidneys and spleen vs. vehicle control, and demonstrated significantly increased efficacy when combined with meropenem (vs either agent alone). CONCLUSIONS: CF-370 is the first engineered lysin described with potent broad spectrum in vitro activity against multiple clinically-relevant Gram-negative pathogens, as well as potent in vivo efficacy in an animal model of severe invasive multi-system infection.

9.
J Infect Dis ; 229(6): 1648-1657, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38297970

RESUMEN

BACKGROUND: Staphylococcus aureus is the most common cause of life-threatening endovascular infections, including infective endocarditis (IE). These infections, especially when caused by methicillin-resistant strains (MRSA), feature limited therapeutic options and high morbidity and mortality rates. METHODS: Herein, we investigated the role of the purine biosynthesis repressor, PurR, in virulence factor expression and vancomycin (VAN) treatment outcomes in experimental IE due to MRSA. RESULTS: The PurR-mediated repression of purine biosynthesis was confirmed by enhanced purF expression and production of an intermediate purine metabolite in purR mutant strain. In addition, enhanced expression of the transcriptional regulators, sigB and sarA, and their key downstream virulence genes (eg, fnbA, and hla) was demonstrated in the purR mutant in vitro and within infected cardiac vegetations. Furthermore, purR deficiency enhanced fnbA/fnbB transcription, translating to increased fibronectin adhesion versus the wild type and purR-complemented strains. Notably, the purR mutant was refractory to significant reduction in target tissues MRSA burden following VAN treatment in the IE model. CONCLUSIONS: These findings suggest that the purine biosynthetic pathway intersects the coordination of virulence factor expression and in vivo persistence during VAN treatment, and may represent an avenue for novel antimicrobial development targeting MRSA.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Endocarditis Bacteriana , Staphylococcus aureus Resistente a Meticilina , Purinas , Proteínas Represoras , Infecciones Estafilocócicas , Vancomicina , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Animales , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Purinas/biosíntesis , Antibacterianos/farmacología , Vancomicina/farmacología , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/tratamiento farmacológico , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Ratones , Regulación Bacteriana de la Expresión Génica , Modelos Animales de Enfermedad , Pruebas de Sensibilidad Microbiana , Humanos
10.
BMC Genomics ; 25(1): 325, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561670

RESUMEN

BACKGROUND: Non-coding RNA is a key epigenetic regulation factor during skeletal muscle development and postnatal growth, and miR-542-3p was reported to be conserved and highly expressed in the skeletal muscle among different species. However, its exact functions in the proliferation of muscle stem cells and myogenesis remain to be determined. METHODS: Transfection of proliferative and differentiated C2C12 cells used miR-542-3p mimic and inhibitor. RT-qPCR, EdU staining, immunofluorescence staining, cell counting kit 8 (CCK-8), and Western blot were used to evaluate the proliferation and myogenic differentiation caused by miR-542-3p. The dual luciferase reporter analysis and rescued experiment of the target gene were used to reveal the molecular mechanism. RESULTS: The data shows overexpression of miR-542-3p downregulation of mRNA and protein levels of proliferation marker genes, reduction of EdU+ cells, and cellular vitality. Additionally, knocking it down promoted the aforementioned phenotypes. For differentiation, the miR-542-3p gain-of-function reduced both mRNA and protein levels of myogenic genes, including MYOG, MYOD1, et al. Furthermore, immunofluorescence staining immunized by MYHC antibody showed that the myotube number, fluorescence intensity, differentiation index, and myotube fusion index all decreased in the miR-542-3p mimic group, compared with the control group. Conversely, these phenotypes exhibited an increased trend in the miR-542-3p inhibitor group. Mechanistically, phosphatase and tensin homolog (Pten) was identified as the bona fide target gene of miR-542-3p by dual luciferase reporter gene assay, si-Pten combined with miR-542-3p inhibitor treatments totally rescued the promotion of proliferation by loss-function of miR-542-3p. CONCLUSIONS: This study indicates that miR-542-3p inhibits the proliferation and differentiation of myoblast and Pten is a dependent target gene of miR-542-3p in myoblast proliferation, but not in differentiation.


Asunto(s)
MicroARNs , MicroARNs/genética , MicroARNs/metabolismo , Epigénesis Genética , Proliferación Celular/genética , Diferenciación Celular/genética , ARN Mensajero/metabolismo , Desarrollo de Músculos/genética , Mioblastos , Luciferasas/genética , Luciferasas/metabolismo
11.
J Am Chem Soc ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597345

RESUMEN

Deubiquitinase-targeting chimeras (DUBTACs) have been recently developed to stabilize proteins of interest, which is in contrast to targeted protein degradation (TPD) approaches that degrade disease-causing proteins. However, to date, only the OTUB1 deubiquitinase has been utilized to develop DUBTACs via an OTUB1 covalent ligand, which could unexpectedly compromise the endogenous function of OTUB1 owing to its covalent nature. Here, we show for the first time that deubiquitinase USP7 can be harnessed for DUBTAC development. Based on a noncovalent ligand of USP7, we developed USP7-based DUBTACs that stabilized the ΔF508-CFTR mutant protein as effectively as the previously reported OTUB1-based DUBTAC. Importantly, using two different noncovalent ligands of USP7, we developed the first AMPK DUBTACs that appear to selectively stabilize different isoforms of AMPKß, leading to elevated AMPK signaling. Overall, these results highlight that, in addition to OTUB1, USP7 can be leveraged to develop DUBTACs, thus significantly expanding the limited toolbox for targeted protein stabilization and the development of novel AMPK DUBTACs as potential therapeutics.

12.
J Am Chem Soc ; 146(11): 7584-7593, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38469801

RESUMEN

Given the prevalent advancements in DNA- and RNA-based PROTACs, there remains a significant need for the exploration and expansion of more specific DNA-based tools, thus broadening the scope and repertoire of DNA-based PROTACs. Unlike conventional A- or B-form DNA, Z-form DNA is a configuration that exclusively manifests itself under specific stress conditions and with specific target sequences, which can be recognized by specific reader proteins, such as ADAR1 or ZBP1, to exert downstream biological functions. The core of our innovation lies in the strategic engagement of Z-form DNA with ADAR1 and its degradation is achieved by leveraging a VHL ligand conjugated to Z-form DNA to recruit the E3 ligase. This ingenious construct engendered a series of Z-PROTACs, which we utilized to selectively degrade the Z-DNA-binding protein ADAR1, a molecule that is frequently overexpressed in cancer cells. This meticulously orchestrated approach triggers a cascade of PANoptotic events, notably encompassing apoptosis and necroptosis, by mitigating the blocking effect of ADAR1 on ZBP1, particularly in cancer cells compared with normal cells. Moreover, the Z-PROTAC design exhibits a pronounced predilection for ADAR1, as opposed to other Z-DNA readers, such as ZBP1. As such, Z-PROTAC likely elicits a positive immunological response, subsequently leading to a synergistic augmentation of cancer cell death. In summary, the Z-DNA-based PROTAC (Z-PROTAC) approach introduces a modality generated by the conformational change from B- to Z-form DNA, which harnesses the structural specificity intrinsic to potentiate a selective degradation strategy. This methodology is an inspiring conduit for the advancement of PROTAC-based therapeutic modalities, underscoring its potential for selectivity within the therapeutic landscape of PROTACs to target undruggable proteins.


Asunto(s)
ADN de Forma Z , Quimera Dirigida a la Proteólisis , Proteolisis , Adenosina Desaminasa/metabolismo , ARN/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas de Unión al ADN/metabolismo
13.
Small ; : e2400516, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38686688

RESUMEN

Chronic wounds constitute an increasingly prevalent global healthcare issue, characterized by recurring bacterial infections, pronounced oxidative stress, compromised functionality of immune cells, unrelenting inflammatory reactions, and deficits in angiogenesis. In response to these multifaceted challenges, the study introduced a stimulus-responsive glycopeptide hydrogel constructed by oxidized Bletilla striata polysaccharide (OBSP), gallic acid-grafted ε-Polylysine (PLY-GA), and paeoniflorin-loaded micelles (MIC@Pae), called OBPG&MP. The hydrogel emulates the structure of glycoprotein fibers of the extracellular matrix (ECM), exhibiting exceptional injectability, self-healing, and biocompatibility. It adapts responsively to the inflammatory microenvironment of chronic wounds, sequentially releasing therapeutic agents to eradicate bacterial infection, neutralize reactive oxygen species (ROS), modulate macrophage polarization, suppress inflammation, and encourage vascular regeneration and ECM remodeling, playing a critical role across the inflammatory, proliferative, and remodeling phases of wound healing. Both in vitro and in vivo studies confirmed the efficacy of OBPG&MP hydrogel in regulating the wound microenvironment and enhancing the regeneration and remodeling of chronic wound skin tissue. This research supports the vast potential for herb-derived multifunctional hydrogels in tissue engineering and regenerative medicine.

14.
BMC Cancer ; 24(1): 462, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38614966

RESUMEN

BACKGROUND: Patients with metastatic gastric cancer (mGC) have poor prognosis. This real-world study aimed to describe treatment regimens and survival of mGC patients. METHODS: A retrospective analysis was conducted using anonymized German claims data (AOK PLUS) covering a period from 2010 to 2021. The study population included newly diagnosed mGC cases identified from 2011 to 2020. The index date was defined as the first diagnosis of metastasis on or after gastric cancer diagnosis. Therapy regimens were identified based on inpatient and outpatient data, and subsequently stratified by line of treatment. Survival analyses were conducted using the Kaplan-Meier method. RESULTS: The cohort consisted of 5,278 mGC incident cases (mean age: 72.7 years; male: 61.9%). Nearly half of the incident cases received mGC-related treatment (49.8%). Treated patients were more often male, younger, and had fewer comorbidities compared to untreated patients. Of the 2,629 mGC patients who started the first line of treatment (1LOT), 32.8% switched to 2LOT, and 10.2% reached 3LOT. Longer survival time was observed among disease-specific treated cases compared with untreated cases (median real-world overall survival (rwOS): 12.7 months [95%CI 12.1 - 13.3 months] vs. 3.7 months [95%CI 3.4 - 4.0 months]). CONCLUSION: Systemic therapy was not received in almost half of the mGC patients. In those patients, a very short median rwOS was observed. Treatment patterns were generally in line with the guideline recommendations, however, therapy switching rates and poor prognosis indicate high unmet needs also in the treated population.


Asunto(s)
Neoplasias del Bazo , Neoplasias Gástricas , Humanos , Masculino , Anciano , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/terapia , Estudios Retrospectivos , Pacientes Internos , Pacientes Ambulatorios , Alemania/epidemiología
15.
Langmuir ; 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326982

RESUMEN

In this work, the interaction performance of zwitterionic surfactant [dodecyl dimethyl sulfopropyl betaine (DSB-12) and hexadecyl dimethyl sulfopropyl betaine (DSB-16)] at the n-octadecane oil surface is investigated from experimental and simulation insights. For a macroscopic experiment, interfacial interferometry technology was developed for real-time monitor interaction performances and to obtain the quantitative interfacial thickness and mass results. The Langmuir model was characterized by thermodynamic analysis, deducing the aggregation spontaneity of DSB-16 > DSB-12 with ΔGagg(DSB-16) = -5.94 kJ mol-1 < ΔGagg(DSB-12) = 24.08 kJ mol-1. A three-step dynamic model (adsorption, arrangement, and aggregation) was characterized by kinetic analysis, indicating arrangement process as slow-limiting step with k2(arr) < k1(ads), k3(agg). For microscopic simulation, and molecular dynamic (MD) method was utilized to theoretically investigate interaction performances and obtain the interfacial configuration and energy results. The interaction stability and interaction strength were indicated to be DSB-16 > DSB-12 with differences of final energy ΔEfin = 48-88 kcal mol-1. The interaction mechanism was explained by proposing the model of "response enhancement" and "deposition activity" for DSB-16 interactions, and "response decrease" and "elution activity" for DSB-12 interactions. The different performances can be attributed to the different interaction forms and forces of surfactants. This work provided a platform for performance and mechanism investigation between the surfactant molecule and oil surface, which is of great significance in reservoir exploitation and enhanced oil recovery (EOR).

16.
Langmuir ; 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38343075

RESUMEN

Investigation of asphaltene adsorption at rock surfaces plays an important role in enhanced oil recovery (EOR) for the petroleum industry. In this work, the interaction performances of asphaltene adsorption at carbonate dolomite and calcite surfaces are investigated based on experimental and simulation insights. On the one hand, macroscopic interaction performances were investigated by spectroscopy experiments to obtain the Langmuir thermodynamic model and pseudo-second-order (PSO) kinetic model. The results indicated monolayer molecular asphaltene adsorption for both dolomite and calcite, while they showed 'slow adsorption-slow desorption' for dolomite but 'fast adsorption-fast desorption' for calcite. Meanwhile, dolomite showed a higher adsorption capacity with qm(dol 1) = 5.35 mg/g > qm(cal 1) = 1.28 mg/g and a stronger adsorption spontaneity with ΔGm(dol 1)θ = -7.76 kJ/mol < ΔGm(cal 1)θ = -4.76 kJ/mol. On the other hand, microscopic interaction performances were investigated for three asphaltene molecules by molecular dynamics simulation (MDS) with ∼8 Å distance-placing and 500 ps time-running. According to the results, dolomite showed higher system stability than calcite with a lower final energy of ΔEdol-cal = -58 kJ/mol, and archipelago asphaltene showed higher adsorption stability with the smallest equilibrium energy of Earch(dol) = -147 kJ/mol for albite and Earch(cal) = -89 kJ/mol for calcite. The model of molecular orientation and force dominance was proposed as the interaction mechanism for asphaltene adsorption, which "lie sideways" at low concentrations but "stands upright" at high concentrations. This work allows the performance investigation and mechanism illustration of asphaltene adsorption at rock surfaces, which can help gain a fundamental understanding of the EOR during reservoir exploitation.

17.
Inorg Chem ; 63(14): 6564-6570, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38531079

RESUMEN

Extensive research has been dedicated to exploring the potential applications of organic-inorganic hybrid metal halides in optoelectronics. This study presents findings on three metal halides based on phenylbutanammonium (PBA). Specifically, (PBA)2MnBr4(H2O)2 and (PBA)2Sn(IV)Cl6 exhibit zero-dimensional structures with P21/c and Pnma space groups, respectively, while (PBA)2Sn(II)Br4 features a two-dimensional structure with P1̅ space group. Under UV excitation, (PBA)2MnBr4(H2O)2 exhibits double emission arising from the 4T1 → 6A1 transitions of Mn2+ in two distinct coordination environments. The emission spectrum of (PBA)2SnCl6 aligns with that of PBACl, suggesting that the luminescence originates from the organic component. The yellow emission of (PBA)2SnBr4 is attributed to the self-trapped excitons. This study introduces the PBA series of compounds, revealing that varying metal ions and halogen combinations can adjust the structural dimensions and influence optical properties. The insights gained from this work serve as a guide for the preparation of efficient white light-emitting diodes.

18.
Org Biomol Chem ; 22(4): 708-713, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38165289

RESUMEN

The introduction of aromatic substituents into organic compounds significantly alters their physical and chemical characteristics. Yet, achieving precise control over the site-selectivity of arylation continues to pose a considerable challenge. We present here a controllable method for the site-selective mono-, di-, and triarylation of pyrazolone with diaryliodonium salts. The method showcases robustness, flexibility, and excellent compatibility with a broad range of functional groups. It enables control over both the site of arylation and the number of aryl additions. Specifically, three of the four substitutable positions in pyrazolone can be selectively arylated, effectively producing four products under controlled conditions. Additionally, the method supports one-pot sequential arylation, leading to an array of products with diverse aromatic substituents. Control experiments revealed the specific conditions of each reaction step.

19.
Future Oncol ; 20(15): 1013-1030, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37814886

RESUMEN

Objective: To evaluate treatment patterns, healthcare resource utilization (HRU) and costs among peripheral T-cell lymphoma (PTCL) patients in the USA. Methods: A retrospective cohort study, using the IQVIA PharMetrics® Plus claims database from 1 April 2011 to 30 November 2021, identified PTCL patients receiving systemic treatments. Three mutually exclusive subcohorts were created based on line of therapy (LOT): 1LOT, 2LOT and ≥3LOT. Common treatment regimens, median time on treatment, all-cause and PTCL-related HRU and costs were estimated. Results: Among 189 PTCL patients identified, 61.9% had 1LOT, 21.7% had 2LOT and 16.4% had ≥3LOT. The most common treatment regimens in the 1LOT were CHOP/CHOP-like, CHOEP/CHOEP-like and brentuximab vedotin; monotherapies were most common in the 2LOT and ≥3LOT. All-cause and PTCL-related hospitalizations and prescriptions PPPM increased with increasing LOT. Nearly 70% of total treatment costs were PTCL related. Conclusion: Higher utilization of combination therapies in the 1LOT and monotherapies in subsequent LOTs were observed, alongside high PTCL-related costs.


Peripheral T-cell lymphomas (PTCL) are a rare and fast-growing form of blood cancer. About 8000­12,000 people in the USA are diagnosed with PTCL every year. As it is a rare disease and has many types, and there is a limited understanding of the patients who have PTCL and the treatments they receive in the real world. The purpose of this study was to evaluate how these patients are treated, what are they treated with and what are the costs of these treatments in the USA. The data collected on these patients was divided into three groups based upon the number of lines of treatment/therapy (LOT) they received: 1LOT, 2LOT and ≥3LOT. This study researched different treatments and their duration in each line of therapy. Among 189 PTCL patients included in the study, the average age of patients was 55 years and 62% were male. Among these patients, 62% had 1LOT, 22% had 2LOT and 16% had ≥3LOT. The most common treatments in the 1LOT were traditional chemotherapy regimens followed by targeted therapies: CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or CHOP-like, CHOEP (cyclophosphamide, doxorubicin, vincristine, etoposide and prednisone) or CHOEP-like, and brentuximab vedotin. Treatment regimens with only one drug were most common in the 2LOT and ≥3LOT. The total cost of PTCL treatment in the USA is very high; 70% of this cost is related to their treatment with various drugs. More research is needed to better understand the treatment and cost of this rare cancer.


Asunto(s)
Linfoma de Células T Periférico , Humanos , Linfoma de Células T Periférico/tratamiento farmacológico , Linfoma de Células T Periférico/epidemiología , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Brentuximab Vedotina/uso terapéutico , Costos de la Atención en Salud , Doxorrubicina , Ciclofosfamida/uso terapéutico , Vincristina/uso terapéutico , Prednisona
20.
J Craniofac Surg ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38771203

RESUMEN

Osteosarcoma (OS) is a highly malignant tumor, and chemotherapy resistance suggests poor prognosis in OS patients. In this study, the authors discovered that miR-9 has a pro-angiogenic role in OS. The anti-angiogenic effects of cisplatin were greatly increased when miR-9 was suppressed in OS. In addition, the authors demonstrated that miR-9 plays a pro-angiogenic role by targeting apoptosis-inducing factor 1 (APE1) in OS. Importantly, our in vivo experiments showed that inhibition of miR-9 combined with cisplatin could suppress xenograft tumor growth by targeting APE1 and decreasing angiogenesis in OS. In summary, our results suggest that miR-9 plays a role as a tumor promoter, and inhibiting miR-9 and APE1 is a new strategy for inhibiting OS angiogenesis and chemotherapy resistance.

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