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1.
Cell ; 187(15): 3936-3952.e19, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38936359

RESUMEN

Duplication is a foundation of molecular evolution and a driver of genomic and complex diseases. Here, we develop a genome editing tool named Amplification Editing (AE) that enables programmable DNA duplication with precision at chromosomal scale. AE can duplicate human genomes ranging from 20 bp to 100 Mb, a size comparable to human chromosomes. AE exhibits activity across various cell types, encompassing diploid, haploid, and primary cells. AE exhibited up to 73.0% efficiency for 1 Mb and 3.4% for 100 Mb duplications, respectively. Whole-genome sequencing and deep sequencing of the junctions of edited sequences confirm the precision of duplication. AE can create chromosomal microduplications within disease-relevant regions in embryonic stem cells, indicating its potential for generating cellular and animal models. AE is a precise and efficient tool for chromosomal engineering and DNA duplication, broadening the landscape of precision genome editing from an individual genetic locus to the chromosomal scale.


Asunto(s)
Duplicación de Gen , Edición Génica , Genoma Humano , Humanos , Edición Génica/métodos , Sistemas CRISPR-Cas/genética , ADN/genética , Animales , Células Madre Embrionarias/metabolismo , Cromosomas Humanos/genética
2.
Cell ; 179(7): 1448-1450, 2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31835025

RESUMEN

Many targeted base transversions, insertions, and deletions remain challenging due to the lack of precise and efficient genome editing technologies. Recently, Anzalone et al. reported a versatile approach to achieve all types of genome edits, shedding new light on correcting most genetic variants associated with diseases.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica/métodos , Animales , Terapia Genética/métodos , Humanos
3.
Nature ; 632(8026): 930-937, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39085602

RESUMEN

The noradrenaline transporter (also known as norepinephrine transporter) (NET) has a critical role in terminating noradrenergic transmission by utilizing sodium and chloride gradients to drive the reuptake of noradrenaline (also known as norepinephrine) into presynaptic neurons1-3. It is a pharmacological target for various antidepressants and analgesic drugs4,5. Despite decades of research, its structure and the molecular mechanisms underpinning noradrenaline transport, coupling to ion gradients and non-competitive inhibition remain unknown. Here we present high-resolution complex structures of NET in two fundamental conformations: in the apo state, and bound to the substrate noradrenaline, an analogue of the χ-conotoxin MrlA (χ-MrlAEM), bupropion or ziprasidone. The noradrenaline-bound structure clearly demonstrates the binding modes of noradrenaline. The coordination of Na+ and Cl- undergoes notable alterations during conformational changes. Analysis of the structure of NET bound to χ-MrlAEM provides insight into how conotoxin binds allosterically and inhibits NET. Additionally, bupropion and ziprasidone stabilize NET in its inward-facing state, but they have distinct binding pockets. These structures define the mechanisms governing neurotransmitter transport and non-competitive inhibition in NET, providing a blueprint for future drug design.


Asunto(s)
Apoproteínas , Bupropión , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática , Norepinefrina , Piperazinas , Tiazoles , Humanos , Regulación Alostérica/efectos de los fármacos , Apoproteínas/antagonistas & inhibidores , Apoproteínas/química , Apoproteínas/metabolismo , Sitios de Unión , Transporte Biológico , Bupropión/química , Bupropión/metabolismo , Bupropión/farmacología , Cloruros/química , Cloruros/metabolismo , Conotoxinas/química , Conotoxinas/metabolismo , Conotoxinas/farmacología , Modelos Moleculares , Norepinefrina/química , Norepinefrina/metabolismo , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/metabolismo , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/química , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/antagonistas & inhibidores , Piperazinas/química , Piperazinas/metabolismo , Piperazinas/farmacología , Unión Proteica , Conformación Proteica/efectos de los fármacos , Sodio/química , Sodio/metabolismo , Tiazoles/química , Tiazoles/metabolismo , Tiazoles/farmacología
4.
EMBO J ; 42(1): e111703, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36326837

RESUMEN

EXD2 is a recently identified exonuclease that cleaves RNA and DNA in double-stranded (ds) forms. It thus serves as a model system for investigating the similarities and discrepancies between exoribonuclease and exodeoxyribonuclease activities and for understanding the nucleic acid (NA) unwinding-degradation coordination of an exonuclease. Here, using a single-molecule fluorescence resonance energy transfer (smFRET) approach, we show that despite stable binding to both substrates, EXD2 barely cleaves dsDNA and yet displays both exoribonuclease and exodeoxyribonuclease activities toward RNA-DNA hybrids with a cleavage preference for RNA. Unexpectedly, EXD2-mediated hybrid cleavage proceeds in a discrete stepwise pattern, wherein a sudden 4-bp duplex unwinding increment and the subsequent dwell constitute a complete hydrolysis cycle. The relatively weak exodeoxyribonuclease activity of EXD2 partially originates from frequent hybrid rewinding. Importantly, kinetic analysis and comparison of the dwell times under varied conditions reveal two rate-limiting steps of hybrid unwinding and nucleotide excision. Overall, our findings help better understand the cellular functions of EXD2, and the cyclic coupling between duplex unwinding and exonucleolytic degradation may be generalizable to other exonucleases.


Asunto(s)
Exorribonucleasas , ARN , ARN/metabolismo , Exorribonucleasas/genética , Exorribonucleasas/metabolismo , Cinética , ADN/metabolismo , Exodesoxirribonucleasas/metabolismo
5.
Nature ; 599(7884): 325-329, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34552241

RESUMEN

Glutamate-gated kainate receptors are ubiquitous in the central nervous system of vertebrates, mediate synaptic transmission at the postsynapse and modulate transmitter release at the presynapse1-7. In the brain, the trafficking, gating kinetics and pharmacology of kainate receptors are tightly regulated by neuropilin and tolloid-like (NETO) proteins8-11. Here we report cryo-electron microscopy structures of homotetrameric GluK2 in complex with NETO2 at inhibited and desensitized states, illustrating variable stoichiometry of GluK2-NETO2 complexes, with one or two NETO2 subunits associating with GluK2. We find that NETO2 accesses only two broad faces of kainate receptors, intermolecularly crosslinking the lower lobe of ATDA/C, the upper lobe of LBDB/D and the lower lobe of LBDA/C, illustrating how NETO2 regulates receptor-gating kinetics. The transmembrane helix of NETO2 is positioned proximal to the selectivity filter and competes with the amphiphilic H1 helix after M4 for interaction with an intracellular cap domain formed by the M1-M2 linkers of the receptor, revealing how rectification is regulated by NETO2.


Asunto(s)
Proteínas de la Membrana/metabolismo , Receptores de Ácido Kaínico/metabolismo , Microscopía por Crioelectrón , Electrofisiología , Células HEK293 , Humanos , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Proteínas de la Membrana/ultraestructura , Modelos Moleculares , Unión Proteica , Receptores de Ácido Kaínico/química , Receptores de Ácido Kaínico/genética , Receptores de Ácido Kaínico/ultraestructura , Receptor de Ácido Kaínico GluK2
6.
Apoptosis ; 29(9-10): 1309-1329, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38886311

RESUMEN

Disulfidptosis is a novel form of cell death that is distinguishable from established programmed cell death pathways such as apoptosis, pyroptosis, autophagy, ferroptosis, and oxeiptosis. This process is characterized by the rapid depletion of nicotinamide adenine dinucleotide phosphate (NADPH) in cells and high expression of solute carrier family 7 member 11 (SLC7A11) during glucose starvation, resulting in abnormal cystine accumulation, which subsequently induces andabnormal disulfide bond formation in actin cytoskeleton proteins, culminating in actin network collapse and disulfidptosis. This review aimed to summarize the underlying mechanisms, influencing factors, comparisons with traditional cell death pathways, associations with related diseases, application prospects, and future research directions related to disulfidptosis.


Asunto(s)
Muerte Celular , Humanos , Muerte Celular/genética , Animales , Apoptosis/genética , NADP/metabolismo , Autofagia/genética , Glucosa/metabolismo , Ferroptosis/genética
7.
Radiology ; 311(1): e230459, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38563669

RESUMEN

Background Microwave ablation (MWA) is currently under preliminary investigation for the treatment of multifocal papillary thyroid carcinoma (PTC) and has shown promising treatment efficacy. Compared with surgical resection (SR), MWA is minimally invasive and could preserve thyroid function. However, a comparative analysis between MWA and SR is warranted to draw definitive conclusions. Purpose To compare MWA and SR for preoperative US-detected T1N0M0 multifocal PTC in terms of overall and 1-, 3-, and 5-year progression-free survival rates and complication rates. Materials and Methods In this retrospective study, 775 patients with preoperative US-detected T1N0M0 multifocal PTC treated with MWA or SR across 10 centers between May 2015 and December 2021 were included. Propensity score matching (PSM) was performed for patients in the MWA and SR groups, followed by comparisons between the two groups. The primary outcomes were overall and 1-, 3-, and 5-year progression-free survival (PFS) rates and complication rates. Results After PSM, 229 patients (median age, 44 years [IQR 36.5-50.5 years]; 179 female) in the MWA group and 453 patients (median age, 45 years [IQR 37-53 years]; 367 female) in the SR group were observed for a median of 20 months (range, 12-74 months) and 26 months (range, 12-64 months), respectively. MWA resulted in less blood loss, shorter incision length, and shorter procedure and hospitalization durations (all P < .001). There was no evidence of differences in overall and 1-, 3-, or 5-year PFS rates (all P > .05) between MWA and SR (5-year rate, 77.2% vs 83.1%; P = .36) groups. Permanent hoarseness (2.2%, P = .05) and hypoparathyroidism (4.0%, P = .005) were encountered only in the SR group. Conclusion There was no evidence of a significant difference in PFS rates between MWA and SR for US-detected multifocal T1N0M0 PTC, and MWA resulted in fewer complications. Therefore, MWA is a feasible option for selected patients with multifocal T1N0M0 PTC. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Georgiades in this issue.


Asunto(s)
Microondas , Neoplasias de la Tiroides , Humanos , Femenino , Adulto , Persona de Mediana Edad , Microondas/uso terapéutico , Estudios Retrospectivos , Cáncer Papilar Tiroideo/diagnóstico por imagen , Cáncer Papilar Tiroideo/cirugía , Hospitalización , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/cirugía
8.
BMC Cardiovasc Disord ; 24(1): 592, 2024 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-39462324

RESUMEN

BACKGROUND: The effectiveness and adverse effects of coenzyme Q10 for heart failure remain unclear owing to small sample sizes and variations in the quality of existing studies in literature. METHODS: The databases of EMBASE, PubMed, Web of Science, CINAHL databases, Scopus, Cochrane Central Register of Controlled Trials, VIP, Wanfang, and CNKI were searched for randomized controlled trials on the coenzyme Q10-assisted treatment of heart failure. Relevant literature was retrieved, data were extracted, and the risk of bias of the included studies was evaluated by two investigators independently using the Review Manager 5.4 software and the STATA 15 software. RESULTS: In total, 33 studies were included in this meta-analysis, which showed that all-cause mortality [RR = 0.64, 95% CI (0.48, 0.85), P = 0.002; GRADE: moderate quality], hospitalization for heart failure [RR = 0.50, 95% CI (0.37, 0.67), P < 0.00001; GRADE: moderate quality], New York Heart Association classification [MD = - 0.29, 95% CI (- 0.39, - 0.19), P < 0.00001; GRADE: low quality], and brain natriuretic peptide level [MD = - 91.97, 95% CI (- 103.11, - 80.83), P < 0.00001; GRADE: low quality] were lower in the coenzyme Q10 group than in the control group. Meanwhile, left ventricular ejection fraction [MD = 0.51, 95% CI (0.31, 0.71), P < 0.00001; GRADE: low quality] and 6-min walk test result [MD = 31.70, 95% CI (19.96, 43.43), P < 0.00001; GRADE: moderate quality] were better than those in the control group. CONCLUSIONS: According to the existing evidence, coenzyme Q10 reduces all-cause mortality, hospitalization for heart failure, New York Heart Association classification, and brain natriuretic peptide level and improves left ventricular ejection fraction and 6-min walk test result in those with heart failure without major adverse effects. TRIAL REGISTRATION: This study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO, http://www.crd.york.ac.uk/prospero ), with the registration number CRD42023493184.


Asunto(s)
Insuficiencia Cardíaca , Ubiquinona , Función Ventricular Izquierda , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tolerancia al Ejercicio/efectos de los fármacos , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/diagnóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función , Factores de Riesgo , Volumen Sistólico/efectos de los fármacos , Factores de Tiempo , Resultado del Tratamiento , Ubiquinona/análogos & derivados , Ubiquinona/uso terapéutico , Ubiquinona/efectos adversos , Función Ventricular Izquierda/efectos de los fármacos
9.
J Clin Psychol ; 80(2): 279-290, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37847787

RESUMEN

OBJECTIVE: Suicidal ideation and sleep problems are both common in nurses. However, few longitudinal studies are available to examine the temporal association between sleep and suicidal ideation in nurses. METHOD: Data from the Health Longitudinal Survey of Nurses in Shandong Province was analyzed, involving 623 female nurses who had completed data of concern in 2018 (T1) and 2019 (T2). Sleep problem was assessed by the Pittsburgh Sleep Quality Index, in which the transition patterns for global and specific sleep component and the cumulative number of sleep component problems were defined. Suicidal ideation was measured by the ninth item of the Patient Health Questionnaire. Binary logistic regression was used to explore the association between sleep and suicidal ideation. RESULTS: Chronic and deteriorated global sleep problems is associated with a greater risk of suicidal ideation. For the specific component of sleep, sleep disturbance and short sleep duration are associated with a higher risk of suicidal ideation. The higher number of cumulative sleep component problems is associated with a higher risk of suicidal ideation. CONCLUSION: Findings indicate sleep disturbance and short sleep duration may be pathways to suicidal ideation. Initiatives that target at sleep problems may be important to reduce suicidal ideation in nurses.


Asunto(s)
Trastornos del Sueño-Vigilia , Ideación Suicida , Humanos , Femenino , Estudios Prospectivos , Estudios Transversales , Sueño , Trastornos del Sueño-Vigilia/epidemiología , China/epidemiología , Factores de Riesgo
10.
Eur Radiol ; 33(12): 8727-8735, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37466709

RESUMEN

OBJECTIVES: Microwave ablation (MWA) has been widely used for unifocal papillary thyroid carcinoma (U-PTC) and has recently been preliminarily used in multifocal papillary thyroid carcinoma (M-PTC). However, the efficacy and safety of MWA for M-PTC have not been investigated in large samples. The aim of the present study was to evaluate the efficacy and safety of MWA for M-PTC and compare them with MWA for U-PTC. MATERIALS AND METHODS: This retrospective multicentre study enrolled 504 patients (376 females) who underwent MWA for U-PTC (340 cases) or M-PTC (164 cases) from Jan 2015 to Dec 2020. The median age of the patients was 43 years (age range, 20-80 years). Propensity score matching (PSM) was used to balance the baseline characteristics between M-PTC group and U-PTC group. The tumour progression, tumour disappearance, and complication rates were compared between the two groups. RESULTS: The complete ablation was achieved in all enrolled cases in one session. According to the statistical results, no significant differences were shown in tumour progression-free survival (p  = 0.29) or cumulative tumour progression rate (6.7% vs. 4.3%, p  = 0.33) between the M-PTC and U-PTC groups during the follow-up time. However, the tumour disappearance rate in the M-PTC group was lower in the U-PTC group (40.9% vs. 62.8%, p < 0.001), and tumour disappearance was slower in the M-PTC group (p < 0.001). The complication rate showed no significant difference (3.0% vs. 4.9%, p  = 0.571). CONCLUSIONS: MWA is an effective and safe treatment for selected patients with M-PTC, and the prognosis is similar to that of U-PTC. CLINICAL RELEVANCE STATEMENT: The present study provided evidence that compared with unifocal papillary thyroid cancer, microwave ablation could also treat multifocal T1N0M0 papillary thyroid cancer safely with similar clinical outcome, which could promote the application of minimally invasive treatment for papillary thyroid cancer. KEY RESULTS: • Microwave ablation for multifocal and unifocal T1N0M0 papillary thyroid carcinoma had similar tumour progression rates after propensity score matching (6.7% vs. 4.3%, p = 0.33). • The tumour disappearance rate in the multifocal group was lower than that in the unifocal group (40.9% vs. 62.8%, p < 0.001), and tumour disappearance was slower in the multifocal group (p < 0.001). • Tumour size, number, and location were not risk factors for tumour progression in the multifocal papillary thyroid cancer group.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Femenino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Cáncer Papilar Tiroideo/cirugía , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Estudios Retrospectivos , Resultado del Tratamiento , Microondas/uso terapéutico , Carcinoma Papilar/cirugía , Carcinoma Papilar/patología
11.
Nanotechnology ; 34(41)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37379820

RESUMEN

The revolutionary products obtained from atomic and close-to-atomic scale manufacturing (ACSM) has motivated people to conduct more in-depth research. There is a pressing need to surpass the constraints of current technology and achieve precise construction at the atomic scale. The emergence of DNA nanotechnology has enabled DNA to serve as a template for precisely localizing functional components. These advantages of DNA in bottom-up manufacturing give it great potential in ACSM. From this perspective, we review the ability of DNA to accurately build complex structures and discuss its application and prospects in precise atomic manipulation. Finally, opportunities and challenges for DNA in ACSM are systematically summarized.


Asunto(s)
ADN , Nanotecnología , Humanos , ADN/química
12.
Proc Natl Acad Sci U S A ; 117(24): 13499-13508, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32467165

RESUMEN

The existence of multiple serotypes renders vaccine development challenging for most viruses in the Enterovirus genus. An alternative and potentially more viable strategy for control of these viruses is to develop broad-spectrum antivirals by targeting highly conserved proteins that are indispensable for the virus life cycle, such as the 3C protease. Previously, two single-chain antibody fragments, YDF and GGVV, were reported to effectively inhibit human rhinovirus 14 proliferation. Here, we found that both single-chain antibody fragments target sites on the 3C protease that are distinct from its known drug site (peptidase active site) and possess different mechanisms of inhibition. YDF does not block the active site but instead noncompetitively inhibits 3C peptidase activity through an allosteric effect that is rarely seen for antibody protease inhibitors. Meanwhile, GGVV antagonizes the less-explored regulatory function of 3C in genome replication. The interaction between 3C and the viral genome 5' noncoding region has been reported to be important for enterovirus genome replication. Here, the interface between human rhinovirus 14 3C and its 5' noncoding region was probed by hydrogen-deuterium exchange coupled mass spectrometry and found to partially overlap with the interface between GGVV and 3C. Consistently, prebinding of GGVV completely abolishes interaction between human rhinovirus 14 3C and its 5' noncoding region. The epitopes of YDF and GGVV, therefore, represent two additional sites of therapeutic vulnerability in rhinovirus. Importantly, the GGVV epitope appears to be conserved across many enteroviruses, suggesting that it is a promising target for pan-enterovirus inhibitor screening and design.


Asunto(s)
Antivirales/farmacología , Cisteína Endopeptidasas/química , Enterovirus/efectos de los fármacos , Anticuerpos de Cadena Única/farmacología , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/química , Proteasas Virales 3C , Regiones no Traducidas 5' , Regulación Alostérica , Sitio Alostérico , Secuencia de Aminoácidos , Antivirales/química , Antivirales/metabolismo , Cisteína Endopeptidasas/metabolismo , Enterovirus/enzimología , Epítopos , Genoma Viral , ARN Viral/metabolismo , Anticuerpos de Cadena Única/química , Anticuerpos de Cadena Única/metabolismo , Proteínas Virales/metabolismo
13.
Proc Natl Acad Sci U S A ; 117(44): 27435-27444, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33087559

RESUMEN

Conversion of human pluripotent stem cells from primed to naïve state is accompanied by altered transcriptome and methylome, but glycosphingolipid (GSL) profiles in naïve human embryonic stem cells (hESCs) have not been systematically characterized. Here we showed a switch from globo-(SSEA-3, SSEA-4, and Globo H) and lacto-series (fucosyl-Lc4Cer) to neolacto-series GSLs (SSEA-1 and H type 2 antigen), along with marked down-regulation of ß-1,3-galactosyltransferase (B3GALT5) upon conversion to naïve state. CRISPR/Cas9-generated B3GALT5-knockout (KO) hESCs displayed an altered GSL profile, increased cloning efficiency and intracellular Ca2+, reminiscent of the naïve state, while retaining differentiation ability. The altered GSLs could be rescued through overexpression of B3GALT5. B3GALT5-KO cells cultured with 2iLAF exhibited naïve-like transcriptome, global DNA hypomethylation, and X-chromosome reactivation. In addition, B3GALT5-KO rendered hESCs more resistant to calcium chelator in blocking entry into naïve state. Thus, loss of B3GALT5 induces a distinctive state of hESCs displaying unique GSL profiling with expression of neolacto-glycans, increased Ca2+, and conducive for transition to naïve pluripotency.


Asunto(s)
Diferenciación Celular , Galactosiltransferasas/metabolismo , Glicoesfingolípidos/metabolismo , Células Madre Pluripotentes/metabolismo , Antígenos Embrionarios Específico de Estadio/metabolismo , Sistemas CRISPR-Cas/genética , Línea Celular , Células Madre Embrionarias , Galactosiltransferasas/genética , Técnicas de Silenciamiento del Gen , Humanos
14.
Molecules ; 28(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36615631

RESUMEN

Chiral 2-substituted chromanes are important substructures in organic synthesis and appear in numerous natural products. Herein, the correlation between specific optical rotations (SORs) and the stereochemistry at C2 of chiral 2-substituted chromanes was investigated through data mining, quantum-chemical calculations using density functional theory (DFT), and mechanistic analyses. For 2-aliphatic (including acyloxy and alkenyl) chromanes, the P-helicity of the dihydropyran ring usually corresponds to a positive SOR; however, 2-aryl chromanes with P-helicity tend to exhibit negative SORs. 2-Carboxyl (including alkoxycarbonyl and carbonyl) chromanes often display small experimental SORs, and theoretical calculations for them are prone to error because of the fluctuating conformational distribution with computational parameters. Several typical compounds were discussed, including detailed descriptions of the asymmetric synthesis, absolute configuration (AC) assignment methods, and systematic conformational analysis. We hope this work will enrich the knowledge of the stereochemistry of chiral 2-substituted chromanes.


Asunto(s)
Rotación Óptica , Conformación Molecular
15.
J Environ Sci (China) ; 126: 249-262, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36503753

RESUMEN

AgCl/ZnO/g-C3N4, a visible light activated ternary composite catalyst, was prepared by combining calcination, hydrothermal reaction and in-situ deposition processes to treat/photocatalyse tetracycline hydrochloride (TC-HCl) from pharmaceutical wastewater under visible light. The morphological, structural, electrical, and optical features of the novel photocatalyst were characterized using scanning electron microscopy (SEM), UV-visible light absorption spectrum (UV-Vis DRS), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and transient photocurrent techniques. All analyses confirmed that the formation of heterojunctions between AgCl/ZnO and g-C3N4 significantly increase electron-hole transfer and separation compared to pure ZnO and g-C3N4. Thus, AgCl/ZnO/g-C3N4 could exhibit superior photocatalytic activity during TC-HCl assays (over 90% removal) under visible light irradiation. The composite could maintain its photocatalytic stability even after four consecutive reaction cycles. Hydrogen peroxide (H2O2) and superoxide radical (·O2) contributed more than holes (h+) and hydroxyl radicals (·OH) to the degradation process as showed by trapping experiments. Liquid chromatograph-mass spectrometer (LC-MS) was used for the representation of the TC-HCl potential degradation pathway. The applicability and the treatment potential of AgCl/ZnO/g-C3N4 against actual pharmaceutical wastewater showed that the composite can achieve removal efficiencies of 81.7%, 71.4% and 69.0% for TC-HCl, chemical oxygen demand (COD) and total organic carbon (TOC) respectively. AgCl/ZnO/g-C3N4 can be a prospective key photocatalyst in the field of degradation of persistent, hardly-degradable pollutants, from industrial wastewater and not only.


Asunto(s)
Tetraciclina , Aguas Residuales , Peróxido de Hidrógeno , Estudios Prospectivos , Espectroscopía Infrarroja por Transformada de Fourier , Luz , Preparaciones Farmacéuticas
16.
Angew Chem Int Ed Engl ; 62(13): e202219299, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36734471

RESUMEN

The activation of water molecules in thermal catalysis typically requires high temperatures, representing an obstacle to catalyst development for the low-temperature water-gas shift reaction (WGSR). Plasmonic photocatalysis allows activation of water at low temperatures through the generation of light-induced hot electrons. Herein, we report a layered double hydroxide-derived copper catalyst (LD-Cu) with outstanding performance for the low-temperature photo-driven WGSR. LD-Cu offered a lower activation energy for WGSR to H2 under UV/Vis irradiation (1.4 W cm-2 ) compared to under dark conditions. Detailed experimental studies revealed that highly dispersed Cu nanoparticles created an abundance of hot electrons during light absorption, which promoted *H2 O dissociation and *H combination via a carboxyl pathway, leading to the efficient production of H2 . Results demonstrate the benefits of exploiting plasmonic phenomena in the development of photo-driven low-temperature WGSR catalysts.

17.
Bioorg Med Chem ; 65: 116757, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35504209

RESUMEN

Polycyclic aromatic systems have been considered good biological probes, but some may also be good scaffolds for drug development. In this study, a series of benzobis(imidazole) derivatives were identified as STAT3 signal inhibitors, among which compound 24 showed significant inhibition of IL-6 induced JAK/STAT3 signalling pathway activation. Moreover, 24 inhibited cancer cell growth and migration, and induced cell apoptosis as well as cycle arrest in human hepatocellular carcinoma cells (HepG2) and oesophageal carcinoma cells (EC109). Compound 24 also displayed obvious antitumor activity in a mouse HepG2 cell xenograft tumor model without affecting the body weight. These results confirmed that 24 was a potential STAT3 signal inhibitor with certain antitumor activity.


Asunto(s)
Neoplasias Hepáticas , Animales , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Humanos , Imidazoles , Neoplasias Hepáticas/patología , Ratones , Ratones Desnudos , Fosforilación , Factor de Transcripción STAT3/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Int J Hyperthermia ; 39(1): 8-14, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34936851

RESUMEN

PURPOSE: To assess the absorption rate and factors related to the development of benign thyroid nodules (BTNs) following image-guided microwave ablation (MWA). MATERIALS AND METHODS: This retrospective study reviewed nodule efficacy in patients who underwent MWA of BTNs between January 2016 and January 2018. The endpoint was a third-year follow-up. Nodules were categorized into those showing complete absorption (volumes with less than 100% volume reduction ratio (VRR) and those showing partial absorption (100% VRR)). Univariable and multivariable regression analyses were carried out to identify variables that were associated with nodule absorption rates. RESULTS: A total of 173 BTNs (median volume= 4.23 ml; 25-75 percentiles= 2.27-9.00 ml) from 173 patients were evaluated. 49.7% (86/173) of patients had nodules that became completely absorbed. The mean VRRs of all BTNs were 18.0%, 78.7%, 89.0%, 94.5%, and 97.1% at the 1-, 6-,12-, 24- and 36- month follow-ups. At the 3-year follow-up time point, nodule characteristics related to nodule VRR included nodule volume (adjusted odds ratio [AOR], 1.1 [95% CI: 1.0, 1.2]; p = 0.03) and nodule margin (AOR, 5.3 [95% CI: 1.8, 16.0]; p < 0.01). Treatment-related characteristics included energy per ml in nodular volume (AOR, 1.0 [95% CI: 1.0, 1.0]; p < 0.01) and blockage of peripheral flow (AOR, 3.3 [95% CI: 1.3 8.3]; p = 0.01). CONCLUSIONS: US-guided image-guided MWA results in satisfactory long-term outcomes for the patients with BTNs. Factors related to nodule absorption rate were the volume and margin of the nodule, energy per ml in nodular volume and blockage of peripheral flow.


Asunto(s)
Ablación por Catéter , Nódulo Tiroideo , Ablación por Catéter/métodos , Estudios de Seguimiento , Humanos , Microondas/uso terapéutico , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/cirugía , Resultado del Tratamiento
19.
Chirality ; 34(10): 1355-1370, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35904531

RESUMEN

Chirality is one of the key factors affecting the medicinal efficacy of compounds. In addition to central chirality, sterically hindered chiral axes commonly appear in drugs and the resulting chirality is known as atropisomerism. With developments in medicinal chemistry, atropisomerism has attracted increasing attention. This review discusses the classification, biological activity, pharmacokinetics, toxicity and side effects of atropisomers, and can serve as a reference in the research and development of potential chiral drugs.


Asunto(s)
Estereoisomerismo
20.
Eur Arch Otorhinolaryngol ; 279(1): 399-413, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33821328

RESUMEN

OBJECTIVE: The objective of this study is to identify valuable prognostic factors, build clinical prediction nomograms, and recommend the optimal therapeutic strategy for patients with initially diagnosed glottic cancer. METHODS: Patients were extracted from the SEER database. Cox regression analyses, survival analyses, an internal validation, the propensity score analysis, and the competing risk analysis were performed. RESULTS: Nine overlapped factors were considered as valuable prognostic factors. Furthermore, nomograms were established for clinical prediction models to assess the 1-, 3-, and 5-year overall survival (OS) and cancer-specific survival (CSS). C-indexes, receiver operating characteristic curves, calibration curves, and decision curve analyses proved that nomograms showed better predictive accuracy, ability, and prognostic value compared to the American Joint Committee on Cancer stage. For patients in stage I, primary site surgery alone would acquire best OS and CSS. For patients in stage II, primary site surgery and/or radiation would gain better OS and CSS. For patients in stage III, radiation plus chemotherapy or primary site surgery (alone or plus radiation) would acquire better OS and CSS. Moreover, for patients in stage IV, primary site surgery plus radiation would gain better OS and CSS. CONCLUSIONS: Nomograms could be useful for patients' counseling and guide therapeutic decision-making. Primary site surgery alone may likely be the optimal therapy for stage I glottic cancer, and primary site surgery and/or radiation may be the recommended therapy for stage II glottic cancer. The combination treatment would be the preferred choice for advanced-stage (stage III & IV) glottic cancer, and the role of chemotherapy needs to be further explored.


Asunto(s)
Neoplasias Laríngeas , Neoplasias de la Lengua , Humanos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/terapia , Nomogramas , Pronóstico , Programa de VERF , Estados Unidos/epidemiología
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