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1.
J Neurol Sci ; 460: 122988, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38579413

RESUMO

Patients diagnosed with low-pressure hydrocephalus typically present with enlarged ventricles and unusually low intracranial pressure, often measuring below 5 cmH2O or even below atmospheric pressure. This atypical presentation often leads to low recognition and diagnostic rates. The development of low-pressure hydrocephalus is believed to be associated with a decrease in the viscoelasticity of brain tissue or separation between the ventricular and subarachnoid spaces. Risk factors for low-pressure hydrocephalus include subarachnoid hemorrhage, aqueduct stenosis, prior cranial radiotherapy, ventricular shunting, and cerebrospinal fluid leaks. For potential low-pressure hydrocephalus, diagnostic criteria include neurological symptoms related to hydrocephalus, an Evans index >0.3 on imaging, ICP ≤ 5 cm H2O, symptom improvement with negative pressure drainage, and exclusion of ventriculomegaly caused by neurodegenerative diseases. The pathogenesis and pathophysiological features of low-pressure hydrocephalus differ significantly from other types of hydrocephalus, making it challenging to restore normal ventricular morphology through conventional drainage methods. The primary treatment options for low-pressure hydrocephalus involve negative pressure drainage and third ventriculostomy. With appropriate treatment, most patients can regain their previous neurological function. However, in most cases, permanent shunt surgery is still necessary. Low-pressure hydrocephalus is a rare condition with a high rate of underdiagnosis and mortality. Early identification and appropriate intervention are crucial in reducing complications and improving prognosis.

2.
Food Chem ; 450: 139353, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38636376

RESUMO

Understanding neural pathways and cognitive processes involved in the transformation of dietary fats into sensory experiences has profound implications for nutritional well-being. This study presents an efficient approach to comprehending the neural perception of fat taste using electroencephalogram (EEG). Through the examination of neural responses to different types of fatty acids (FAs) in 45 participants, we discerned distinct neural activation patterns associated with saturated versus unsaturated fatty acids. The spectrum analysis of averaged EEG signals revealed notable variations in δ and α-frequency bands across FA types. The topographical distribution and source localization results suggested that the brain encodes fat taste with specific activation timings in primary and secondary gustatory cortices. Saturated FAs elicited higher activation in cortical associated with emotion and reward processing. This electrophysiological evidence enhances our understanding of fundamental mechanisms behind fat perception, which is helpful for guiding strategies to manage hedonic eating and promote balanced fat consumption.

3.
J Exp Bot ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642399

RESUMO

Plant life-history is determined by two transitions, the germination and the flowering times, in which the phosphatidylethanolamine-binding proteins (PEBP) FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1) play key regulatory roles. Compared to the highly conserved TFL1-likes, FT-like genes vary in copy numbers significantly in gymnosperms and monocots of the angiosperms, while sporadic duplications can be observed in eudicots. Here, via a systematic analysis of the PEBPs in angiosperms with a special focus on twelve representative species featuring high-quality genomes in the Lamiales order, we identified a successive lineage-specific but systematic expansion of FT-like genes in the families of core Lamiales. The first expansion event generated FT1-likes mainly via a core-Lamiales-specific whole-genome-duplication (cL-WGD), while on the other hand, a likely random duplication produced the FT2-likes in the lineages containing Scrophulariaceae and rest of the core Lamiales. Both FT1- and FT2-like genes were further amplified tandemly in some families. These expanded FT-likes featured highly diverged expression patterns and structural variation, indicating functional diversification. Intriguingly, some core Lamiales contained the relict MOTHER OF FT AND TFL1 like 2 (MFT2) that likely expanded in the common ancestor of angiosperms. Our data showcase the highly dynamic lineage-specific expansion of the FT-like genes, thus provide important and fresh evolutionary insights into the gene-regulatory-network underpinning flowering time diversity in Lamiales, and more generally, in angiosperms.

4.
RSC Adv ; 14(16): 11151-11156, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38590356

RESUMO

Acute liver failure caused by hepatic ischemia reperfusion injury (HIRI) poses a severe threat to life, emphasizing the urgent need for precise and timely early diagnosis. Viscosity, a key parameter reflecting active analyte levels at the cellular level, remains underexplored in relation to HIRI. To address this gap, we have developed a groundbreaking near-infrared molecule rotator, PN, exhibiting exceptional characteristics. PN demonstrates remarkable sensitivity, with a 32-fold change in response to viscosity, ranging from PBS to glycerol solution. PN's distinctive features include maximum emission wavelength 790 nm, as well as an impressive Stokes shift 190 nm. Moreover, PN exhibits the ability to sensitively and selectively differentiate nystatin-induced viscosity changes within living cells, and can be used for the detection of viscosity changes in the HIRI mouse model. This capability enhances our understanding of cellular responses, opening avenues for potential applications within disease models. The versatility of PN extends to its potential role in guiding timely monitoring and imaging of viscosity, offering valuable insights into disease progression.

5.
Alzheimers Res Ther ; 16(1): 87, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654379

RESUMO

BACKGROUND: While evidence supports cognitive reserve (CR) in preserving cognitive function, longitudinal validation of CR proxies, including later-life factors, remains scarce. This study aims to validate CR's stability over time and its relation to cognitive function in rural Chinese older adults. METHODS: Within the project on the health status of rural older adults (HSRO), the survey included baseline assessment (2019) and follow-up assessment (2022). 792 older adults (mean age: 70.23 years) were followed up. The confirmatory factor analysis (CFA) was constructed using cognitive reserve proxies that included years of formal education, social support, hobbies, and exercise. We examined the longitudinal validity of the CR factor using confirmatory factor analyses and measurement invariance and explored the association of CR with cognition using Spearman's correlation and Generalized Estimating Equations (GEE). RESULTS: The results showed that CR's CFA structure was stable over time (T0, χ2/df: 3.21/2; RMSEA: 0.02, and T1, χ2/df: 7.47/2; RMSEA: 0.05) and that it accepted both configural and metric invariance (Δχ2/df = 2.28/3, P = 0.52). In addition, it was found that CR had a stable positive relationship with cognitive function across time (T0, r = 0.54; T1, r = 0.49). Furthermore, longitudinal CR were associated with MMSE (ß = 2.25; 95%CI = 2.01 ~ 2.49). CONCLUSIONS: This study provided valuable evidence on the stability and validity of cognitive reserve proxy measures in rural Chinese older adults. Our findings suggested that cognitive reserve is associated with cognitive function over time and highlighted the importance of accumulating cognitive reserve in later life.


Assuntos
Reserva Cognitiva , População Rural , Humanos , Reserva Cognitiva/fisiologia , Masculino , Feminino , Idoso , Estudos Longitudinais , China , Estudos de Coortes , Pessoa de Meia-Idade , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Cognição/fisiologia , Reprodutibilidade dos Testes , Idoso de 80 Anos ou mais , População do Leste Asiático
6.
Oncol Rep ; 51(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38456515

RESUMO

After the publication of the article, an interested reader drew to the authors' attention that, in the western blots shown in Fig. 5C and D, a pair of data panels were inadvertently duplicated comparing between panels (C) and (D); in addition, the cell migration data shown in Fig. 7F on p. 1852 were selected incorrectly. The authors have examined their original data, and realize that these errors arose inadvertently as a consequence of their mishandling of their data. The revised versions of Figs. 5 and 7, featuring the corrected data for the caspase-8 experiment in Fig. 5C and alternative data for the cell migration assay experiments in Fig. 7F, are shown on the next two pages. The revised data shown for these Figures do not affect the overall conclusions reported in the paper. All the authors agree to the publication of this corrigendum, and are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish this. Furthermore, the authors apologize to the readership for any inconvenience caused. [Oncology Reports 40: 1843-1854, 2018; DOI: 10.3892/or.2018.6593].

7.
Materials (Basel) ; 17(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38541582

RESUMO

In this research, the adsorption performance of individual atoms on the surface of monolayer graphene surface was systematically investigated using machine learning methods to accelerate density functional theory. The adsorption behaviors of over thirty different atoms on the graphene surface were computationally analyzed. The adsorption energy and distance were extracted as the research targets, and the basic information of atoms (such as atomic radius, ionic radius, etc.) were used as the feature values to establish the dataset. Through feature engineering selection, the corresponding input feature values for the input-output relationship were determined. By comparing different models on the dataset using five-fold cross-validation, the mathematical model that best fits the dataset was identified. The optimal model was further fine-tuned by adjusting of the best mathematical ML model. Subsequently, we verified the accuracy of the established machine learning model. Finally, the precision of the machine learning model forecasts was verified by the method of comparing and contrasting machine learning results with density functional theory. The results suggest that elements such as Zr, Ti, Sc, and Si possess some potential in controlling the interfacial reaction of graphene/aluminum composites. By using machine learning to accelerate first-principles calculations, we have further expanded our choice of research methods and accelerated the pace of studying element-graphene interactions.

8.
CNS Neurosci Ther ; 30(3): e14579, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38497532

RESUMO

AIMS: This study aimed to investigate the resting-state functional connectivity and topologic characteristics of brain networks in patients with diabetic optic neuropathy (DON). METHODS: Resting-state functional magnetic resonance imaging scans were performed on 23 patients and 41 healthy control (HC) subjects. We used independent component analysis and graph theoretical analysis to determine the topologic characteristics of the brain and as well as functional network connectivity (FNC) and topologic properties of brain networks. RESULTS: Compared with HCs, patients with DON showed altered global characteristics. At the nodal level, the DON group had fewer nodal degrees in the thalamus and insula, and a greater number in the right rolandic operculum, right postcentral gyrus, and right superior temporal gyrus. In the internetwork comparison, DON patients showed significantly increased FNC between the left frontoparietal network (FPN-L) and ventral attention network (VAN). Additionally, in the intranetwork comparison, connectivity between the left medial superior frontal gyrus (MSFG) of the default network (DMN) and left putamen of auditory network was decreased in the DON group. CONCLUSION: DON patients altered node properties and connectivity in the DMN, auditory network, FPN-L, and VAN. These results provide evidence of the involvement of specific brain networks in the pathophysiology of DON.


Assuntos
Diabetes Mellitus , Doenças do Nervo Óptico , Humanos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
9.
J Agric Food Chem ; 72(13): 6900-6912, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38513076

RESUMO

As a notorious phytopathogenic virus, the tobacco mosaic virus (TMV) severely reduced the quality of crops worldwide and caused critical constraints on agricultural production. The development of novel virucides is a persuasive strategy to address this predicament. Herein, a series of novel bisamide-decorated benzotriazole derivatives were elaborately prepared and screened. Biological tests implied that the optimized compound 7d possessed the most brilliant antiviral inactive profile (EC50 = 157.6 µg/mL) and apparently surpassed that of commercial ribavirin (EC50 = 442.1 µg/mL) 2.8-fold. The preliminary antiviral mechanism was elaborately investigated via transmission electron microscopy, microscale thermophoresis (MST) determination, RT-qPCR, and Western blot analysis. The results showed that compound 7d blocked the assembly of TMV by binding with coat protein (Kd = 0.7 µM) and suppressed TMV coat protein gene expression and biosynthesis process. Computational simulations indicated that 7d displayed strong H-bonds and pi interactions with TMV coat protein, affording a lower binding energy (ΔGbind = -17.8 kcal/mol) compared with Ribavirin (ΔGbind = -10.7 kcal/mol). Overall, current results present a valuable perception of bisamide decorated benzotriazole derivatives with appreciably virustatic competence and should be profoundly developed as virucidal candidates in agrochemical.


Assuntos
Ribavirina , Vírus do Mosaico do Tabaco , Triazóis , Relação Estrutura-Atividade , Ribavirina/farmacologia , Antivirais/farmacologia , Antivirais/química , Desenho de Fármacos
10.
ACS Appl Mater Interfaces ; 16(13): 16351-16362, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38515323

RESUMO

Poly(ethylene oxide) (PEO)-based electrolytes have been extensively studied for all-solid-state lithium-metal batteries due to their excellent film-forming capabilities and low cost. However, the limited ionic conductivity and poor mechanical strength of the PEO-based electrolytes cannot prevent the growth of undesirable lithium dendrites, leading to the failure of batteries. Metal-organic frameworks (MOFs) are functional materials with a periodic porous structure that can improve the electrochemical performance of PEO-based electrolytes. However, the enhancement effect of MOFs with different metal centers and the interaction mechanism with PEO remain unclear. Herein, MOF-74s with Cu or Ni centers are prepared and used as fillers of PEO-based electrolytes. Adding 15 wt % of Cu-MOF-74 to the PEO-based electrolyte (15%Cu-MOF/P-Li) effectively improves the ionic conductivity, lithium transference number, and mechanical strength of the PEO-based electrolyte simultaneously. Furthermore, the ordered pore channels of Cu-MOF-74 provide uniform Li-ion transport pathways, facilitating homogeneous Li+ deposition. As a result, the lithium symmetric cell with 15%Cu-MOF/P-Li shows stable cycles for 1080 h at 0.1 mA cm-2 and 0.1 mAh cm-2, and the Li | 15% Cu-MOF/P-Li | LFP full cell exhibits a long cycle life up to 200 cycles at 60 °C and 0.5 C, with a capacity retention rate of 89.7%.

11.
Plant Commun ; : 100878, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38475995

RESUMO

Brassicaceae represents an important plant family from both a scientific and economic perspective. However, genomic features related to the early diversification of this family have not been fully characterized, especially upon the uplift of the Tibetan Plateau, which was followed by increasing aridity in the Asian interior, intensifying monsoons in Eastern Asia, and significantly fluctuating daily temperatures. Here, we reveal the genomic architecture that accompanied early Brassicaceae diversification by analyzing two high-quality chromosome-level genomes for Meniocus linifolius (Arabodae; clade D) and Tetracme quadricornis (Hesperodae; clade E), together with genomes representing all major Brassicaceae clades and the basal Aethionemeae. We reconstructed an ancestral core Brassicaceae karyotype (CBK) containing 9 pseudochromosomes with 65 conserved syntenic genomic blocks and identified 9702 conserved genes in Brassicaceae. We detected pervasive conflicting phylogenomic signals accompanied by widespread ancient hybridization events, which correlate well with the early divergence of core Brassicaceae. We identified a successive Brassicaceae-specific expansion of the class I TREHALOSE-6-PHOSPHATE SYNTHASE 1 (TPS1) gene family, which encodes enzymes with essential regulatory roles in flowering time and embryo development. The TPS1s were mainly randomly amplified, followed by expression divergence. Our results provide fresh insights into historical genomic features coupled with Brassicaceae evolution and offer a potential model for broad-scale studies of adaptive radiation under an ever-changing environment.

12.
J Mol Med (Berl) ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441598

RESUMO

Phase separation, also known as biomolecule condensate, participates in physiological processes such as transcriptional regulation, signal transduction, gene expression, and DNA damage repair by creating a membrane-free compartment. Phase separation is primarily caused by the interaction of multivalent non-covalent bonds between proteins and/or nucleic acids. The strength of molecular multivalent interaction can be modified by component concentration, the potential of hydrogen, posttranslational modification, and other factors. Notably, phase separation occurs frequently in the cytoplasm of mitochondria, the nucleus, and synapses. Phase separation in vivo is dynamic or stable in the normal physiological state, while abnormal phase separation will lead to the formation of biomolecule condensates, speeding up the disease progression. To provide candidate suggestions for the clinical treatment of nervous system diseases, this review, based on existing studies, carefully and systematically represents the physiological roles of phase separation in the central nervous system and its pathological mechanism in neurodegenerative diseases.

13.
J Exp Bot ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546444

RESUMO

Floral forms with an increased number of petals, also known as double flower (DF) with great agronomic and economic values, have been selected and conserved in many domesticated plants, particularly in ornamentals. The molecular and genetic mechanisms that control this trait are therefore a hot topic, not only for scientists, but also for breeders. In this review, we summarize the current knowledge on the gene regulatory networks of flower initiation and development and known mutations that lead to variation of petal number in many species. Besides the well-accepted miR172/AP2-like module, for which many questions remain unanswered, we also discuss the current knowledge of other pathways in which mutations also lead to extra-petals formation, such as those involved in meristem development, hormones signaling, epigenetic regulations, and responses to environmental signals. We discuss how the concept of "natural mutants" and the recent advances in genomics and genome editing makes it possible to explore the molecular mechanisms underlying the DF formation, and how such knowledge could contribute to the future breeding and selection of this trait in more crops.

15.
J Phys Chem Lett ; 15(11): 3011-3022, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38465884

RESUMO

The severe performance degradation of low-temperature hydrogen fuel cells upon exposure to trace amounts of carbon monoxide (CO) impurities in reformate hydrogen fuels is one of the challenges that hinders their commercialization. Despite significant efforts that have been made, the CO-tolerance performance of electrocatalysts for the hydrogen oxidation reaction (HOR) is still unsatisfactory. This Perspective discusses the path forward for the rational design of CO-tolerant HOR electrocatalysts. The fundamentals of the CO-tolerant mechanisms on commercialized platinum group metal (PGM) electrocatalysts via either promoting CO electrooxidation or weakening CO adsorption are provided, and comprehensive discussions based on these strategies are presented with typical examples. Given the recent progress, some emerging strategies, including blocking CO diffusion with a barrier layer and developing non-PGM HOR catalysts, are also discussed. We conclude with a discussion of the strengths and limitations of these strategies along with the perspectives of the major challenges and opportunities for future research on CO-tolerant HOR electrocatalysts.

16.
J Phys Chem A ; 128(11): 2049-2057, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38471016

RESUMO

The transition-metal-boron bonding interactions and geometric structures of heterodinuclear transition metal carbonyl cluster cations BM(CO)n+ (M = Co, Ni, and Cu) are studied by a combination of the infrared photodissociation spectroscopy and density functional theory calculations at the B3LYP/def2-TZVP level. The BCu(CO)5+ and BCo(CO)6+ cations are characterized as an (CO)2B-M(CO)3/4+ structure involving an σ-type (OC)2B → M(CO)3,4+ dative bonding with end-on carbonyls, while for BNi(CO)5,6+ complexes with a bridged carbonyl, a 3c-2e bond involving the 5σ electrons of the bridged carbonyl and an electron-sharing bond between the B(CO)2 fragment and the Ni(CO)2,3+ subunits were revealed. Moreover, the fundamental driving force of the exclusive existence of a bridged carbonyl group in the boron-nickel complexes has been demonstrated to stem from the desire of the B and Ni centers for the favorable 8- and 18-electron structures.

17.
Sci Rep ; 14(1): 4552, 2024 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402285

RESUMO

Myocardial infarction is defined as a sudden decrease or interruption in blood flow to the coronary arteries, causing ischemic necrosis of the corresponding cardiomyocytes. It is unclear whether systemic macrovascular alterations are associated with retinal microvascular changes. This study utilized optical coherence tomography angiography (OCTA) to compare variations in conjunctival vascular density and fundus retinal vessel density between patients with myocardial infarction (MI) and healthy controls. This study recruited 16 patients (32 eyes) with MI and 16 healthy controls (32 eyes). The superficial retinal layer (SRL), deep retinal layer (DRL) and conjunctival capillary plexus in each eye were evaluated by OCTA. Parameters measured included the density of the temporal conjunctival capillary, retinal microvascular (MIR) and macrovascular (MAR) alterations and total MIR (TMI). The microvascular density of each retinal region was evaluated by the hemisphere segmentation (SR, SL, IL, and IR), annular partition (C1, C2, C3, C4, C5 and C6), and modified early treatment of diabetic retinopathy study (R, S, L, and I) methods. In the macular area, the superficial and deep retinal microvascular densities displayed notable variations. In the superficial layers, the superficial TMI, superficial MIR, and superficial MAR, as well as densities in the SL, IL, S, L, C1, C2, C5 and C6 regions, were significantly lower in MI patients (p < 0.05 each). In the deep layers, the deep MIR and deep TMI), as well as densities in the SL, IL, L, C1, C2 and C6 regions were significantly lower in MI patients (p < 0.05 each). In contrast, the conjunctival microvascular density was significantly higher in MI patients than in healthy controls (p < 0.001). The microvascular densities measured in the deep and superficial retinal layers and in the conjunctiva differ in MI patients and healthy controls. OCTA is effective in detecting changes in the ocular microcirculation.


Assuntos
Infarto do Miocárdio , Tomografia de Coerência Óptica , Humanos , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Vasos Retinianos/diagnóstico por imagem , Retina/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem
18.
Medicine (Baltimore) ; 103(8): e36206, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394510

RESUMO

RATIONALE: Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized, but uncommon complication in patients with kidney transplantation, which poses challenges in diagnosis and poor prognosis due to its low incidence and nonspecific clinical manifestations. As a routine follow-up examination method for kidney transplant patients, ultrasound (US) plays a significant role in the diagnosis of PTLD. Therefore, it is critical to evaluate the ultrasonic characteristics of PTLD in transplanted kidney patients for early detection and diagnosis. PATIENT CONCERNS: A 59-year-old female patient was unexpectedly found with a mass in the hilum of the transplanted kidney 12th month after transplantation, which gradually grew up in the following 4 months. The latest US examination found hydronephrosis. Contrast-enhanced ultrasound (CEUS) demonstrated a hypo-enhancement pattern in arterial and parenchymal phases and showed a new irregular area lacking perceivable intensification within the mass, which was considered necrosis. Meanwhile, the patient developed an acute increase in serum creatinine from 122 to 195 µmol/L. DIAGNOSIS: A US-guided biopsy was conducted with the final pathological diagnosis of PTLD (polymorphic). INTERVENTIONS: After receiving 3 times of rituximab and symptomatic treatment, blood creatinine returned to normal but the mass was still progressing in the patient. Therefore, the treatment approach was modified to immune-chemotherapy. OUTCOMES: The patient was in a stable condition to date. LESSONS: PTLD is a rare complication in a transplanted kidney. US and CEUS are the preferred imaging methods in renal transplant patients due to their good repeatability and no nephrotoxicity. This case demonstrates that continuous dynamic monitoring by using US and CEUS has significant value in the detection and diagnosis of PTLD in a transplanted kidney, suggesting early clinical intervention to avoid further progression.


Assuntos
Transplante de Rim , Transtornos Linfoproliferativos , Feminino , Humanos , Pessoa de Meia-Idade , Rituximab/uso terapêutico , Transplante de Rim/efeitos adversos , Transtornos Linfoproliferativos/diagnóstico por imagem , Transtornos Linfoproliferativos/etiologia , Rim/diagnóstico por imagem , Rim/patologia
19.
Phys Chem Chem Phys ; 26(9): 7407-7415, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38351849

RESUMO

We explored the size-dependent reactivity of Agn+ (n = 2-22) with O2 under mild conditions and found that only a few sizes of Agn+, with even values of n = 4, 6, 12, 16, 18, and 22, are reactive. Possible structures of Agn+ (n = 2-22) were determined using a genetic algorithm with incomplete local optimizations at the DFT level, and the calculated bonding strengths of O2 on these structures are consistent with experimental observations. Analyses revealed a close relationship between the reactivity of Agn+ with O2 and its HOMO-LUMO gap: cationic silver clusters with a small HOMO-LUMO gap are reactive, which can be rationalized by the covalent character of chemical bonds between Agn+ and O2 involving their frontier orbitals. The peculiar size-dependent HOMO-LUMO gaps and reactivity with O2 correlate with the subtle interplay between the electronic configurations and geometric structures of these silver cluster cations.

20.
Nat Med ; 30(3): 740-748, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38302715

RESUMO

Although antiprogrammed death 1 antibody plus chemotherapy has recently been approved for first-line esophageal squamous cell carcinoma (ESCC), antiprogrammed death-ligand 1 antibody may offer another combination option in this setting. In this multicenter, randomized, double-blinded phase 3 trial a total of 540 adults (aged 18-75 years) with unresectable, locally advanced, recurrent or metastatic ESCC and who had not received systemic treatment were enrolled. All patients were randomized at 2:1 to receive either sugemalimab (an anti-PD-L1 antibody; 1,200 mg) or placebo every 3 weeks for up to 24 months, plus chemotherapy (cisplatin 80 mg m-2 on day 1 plus 5-fluorouracil 800 mg m-2 day-1 on days 1-4) every 3 weeks for up to six cycles. At the prespecified interim analysis this study had met dual primary endpoints. With a median follow-up of 15.2 months, the prolongation of progression-free survival was statistically significant with sugemalimab plus chemotherapy compared with placebo plus chemotherapy (median 6.2 versus 5.4 months, hazard ratio 0.67 (95% confidence interval 0.54-0.82), P = 0.0002) as assessed by blinded independent central review. Overall survival was also superior with sugemalimab chemotherapy (median 15.3 versus 11.5 months, hazard ratio 0.70 (95% confidence interval 0.55-0.90, P = 0.0076). A significantly higher objective response rate (60.1 versus 45.2%) as assessed by blinded independent central review was observed with sugemalimab chemotherapy. The incidence of grade 3 or above treatment-related adverse events (51.3 versus 48.4%) was comparable between the two groups. Sugemalimab plus chemotherapy significantly prolonged progression-free survival and overall survival in treatment-naïve patients with advanced ESCC, with no unexpected safety signal. The ClinicalTrials.gov identifier is NCT04187352 .


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Adulto , Humanos , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/induzido quimicamente , Pessoa de Meia-Idade , Idoso
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