Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 910
Filtrar
1.
N Engl J Med ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842520

RESUMEN

BACKGROUND: In a phase 3 trial, bulevirtide monotherapy led to a virologic response in patients with chronic hepatitis D. Pegylated interferon (peginterferon) alfa-2a is recommended by guidelines as an off-label treatment for this disease. The role of combination therapy with bulevirtide and peginterferon alfa-2a, particularly with regard to finite treatment, is unclear. METHODS: In this phase 2b, open-label trial, we randomly assigned patients to receive peginterferon alfa-2a alone (180 µg per week) for 48 weeks; bulevirtide at a daily dose of 2 mg or 10 mg plus peginterferon alfa-2a (180 µg per week) for 48 weeks, followed by the same daily dose of bulevirtide for 48 weeks; or bulevirtide at a daily dose of 10 mg alone for 96 weeks. All the patients were followed for 48 weeks after the end of treatment. The primary end point was an undetectable level of hepatitis D virus (HDV) RNA at 24 weeks after the end of treatment. The primary comparison was between the 10-mg bulevirtide plus peginterferon alfa-2a group and the 10-mg bulevirtide monotherapy group. RESULTS: A total of 24 patients received peginterferon alfa-2a alone, 50 received 2 mg and 50 received 10 mg of bulevirtide plus peginterferon alfa-2a, and 50 received 10 mg of bulevirtide monotherapy. At 24 weeks after the end of treatment, HDV RNA was undetectable in 17% of the patients in the peginterferon alfa-2a group, in 32% of those in the 2-mg bulevirtide plus peginterferon alfa-2a group, in 46% of those in the 10-mg bulevirtide plus peginterferon alfa-2a group, and in 12% of those in the 10-mg bulevirtide group. For the primary comparison, the between-group difference was 34 percentage points (95% confidence interval, 15 to 50; P<0.001). At 48 weeks after the end of treatment, HDV RNA was undetectable in 25% of the patients in the peginterferon alfa-2a group, in 26% of those in the 2-mg bulevirtide plus peginterferon alfa-2a group, in 46% of those in the 10-mg bulevirtide plus peginterferon alfa-2a group, and in 12% of those in the 10-mg bulevirtide group. The most frequent adverse events were leukopenia, neutropenia, and thrombocytopenia. The majority of adverse events were of grade 1 or 2 in severity. CONCLUSIONS: The combination of 10-mg bulevirtide plus peginterferon alfa-2a was superior to bulevirtide monotherapy with regard to an undetectable HDV RNA level at 24 weeks after the end of treatment. (Funded by Gilead Sciences; MYR 204 ClinicalTrials.gov number, NCT03852433.).

2.
Transl Androl Urol ; 13(5): 720-735, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38855604

RESUMEN

Background: Radiologists currently accept the concept of "interfascial plane (IFP)" to understand retroperitoneal anatomy, replacing Meyers' classic tricompartmental theory. Despite much research on retroperitoneal anatomy, its anatomical structure, embryonic origin and developmental process still require further exploration to guide the optimization of surgical process. This study aims to explore the anatomical basis of IFP related to laparoscopic upper retroperitoneal surgery (LURS) and to compare the clinical outcomes of trans-interfascial plane procedures for LURS (TIFP-LURS) with conventional LURS (Con-LURS). Methods: The study consisted of two parts: cadaveric and clinical study. The cadaveric study involved dissecting and observing the retroperitoneal fasciae and IFP in 32 cadavers using gross anatomical and histological methods. This retrospective clinical study compared the perioperative data and complications of 229 patients who underwent TIFP-LURS and 121 patients who underwent Con-LURS for upper retroperitoneal lesions at our center. Results: The cadaveric study revealed that the retroperitoneal space was composed of multilaminar fasciae that formed potential bloodless spaces among them, that could be used as surgical landmarks and operating planes. The clinical study showed that TIFP-LURS had a significantly less estimated blood loss, lower intraoperative complication rate, lower postoperative complication rate, shorter hospital-stay and lower long-term postoperative complications rate than Con-LURS. Multivariate analysis indicated that the TIFP procedure was an independent protective factor for decreasing the risk of postoperative complications. Conclusions: The IFP are potential avascular spaces that can be used during laparoscopic surgery, and TIFP-LURS is a novel surgical approach that can improve the safety and efficacy of laparoscopic surgery for upper retroperitoneal lesions.

3.
J Cancer Res Clin Oncol ; 150(6): 293, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842687

RESUMEN

The TOR1B gene is known to play a pivotal role in maintaining cellular homeostasis and responding to endoplasmic reticulum stress. However, its involvement in cancer remains relatively understudied. This study seeks to explore the prognostic implications of TOR1B across various cancers, with a specific focus on Basal-like Breast Cancer (BLBC) and its underlying cellular mechanisms. Through comprehensive analysis of data from TCGA, TARGET, GEO, and GTEx, we investigated TOR1B expression and its correlation with patient outcomes. Furthermore, in vitro experiments conducted on BLBC cell lines examined the impact of TOR1B modulation on cell viability, apoptosis, and metabolic activity under varying oxygen levels. Our statistical analysis encompassed differential expression analysis, survival analysis, and multivariate Cox regression. Our findings indicate that TOR1B is overexpressed in BLBC and other cancers, consistently correlating with poorer prognosis. Elevated TOR1B levels were significantly associated with reduced overall and disease-free survival in BLBC patients. In vitro experiments further revealed that TOR1B knockdown augmented apoptosis and influenced metabolic activity, particularly under hypoxic conditions, highlighting its potential role in cancer cell adaptation to stress. Overall, our study underscores the importance of TOR1B in cancer progression, particularly in BLBC, where it serves as a notable prognostic indicator. The interaction between TOR1B and metabolic pathways, as well as its regulation by HIF-1α, suggests its significance in adapting to hypoxia, thereby positioning TOR1B as a promising therapeutic target for aggressive breast cancer subtypes.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Pronóstico , Línea Celular Tumoral , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Apoptosis
5.
Front Plant Sci ; 15: 1337638, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38803601

RESUMEN

Efficient obstacle-avoidance path planning is critical for orchards with numerous irregular obstacles. This paper presents a continuous bidirectional Quick-RRT* (CBQ-RRT*) algorithm based on the bidirectional RRT (Bi-RRT) and Quick-RRT* algorithms and proposes an expansion cost function that evaluates path smoothness and length to overcome the limitations of the Quick-RRT* algorithm for non-holonomic mobile robot applications. To improve the zigzag between dual trees caused by the dual-tree expansion of the Bi-RRT algorithm, CBQ-RRT* proposes the CreateConnectNode optimization method, which effectively solves the path smoothness problem at the junction of dual trees. Simulations conducted on the ROS platform showed that the CBQ-RRT* outperformed the unidirectional Quick-RRT* in terms of efficiency for various orchard layouts and terrain conditions. Compared to Bi-RRT*, CBQ-RRT* reduced the average path length and maximum heading angle by 8.5% and 21.7%, respectively. In addition, field tests confirmed the superior performance of the CBQ-RRT*, as evidenced by an average maximum path lateral error of 0.334 m, a significant improvement over Bi-RRT* and Quick-RRT*. These improvements demonstrate the effectiveness of the CBQ-RRT* in complex orchard environments.

6.
Front Endocrinol (Lausanne) ; 15: 1365321, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38779454

RESUMEN

Background: Adrenocortical carcinoma (ACC) is an aggressive endocrine malignancy with limited therapeutic options. Treating advanced ACC with mitotane, the cornerstone therapy, remains challenging, thus underscoring the significance to predict mitotane response prior to treatment and seek other effective therapeutic strategies. Objective: We aimed to determine the efficacy of mitotane via an in vitro assay using patient-derived ACC cells (PDCs), identify molecular biomarkers associated with mitotane response and preliminarily explore potential agents for ACC. Methods: In vitro mitotane sensitivity testing was performed in 17 PDCs and high-throughput screening against 40 compounds was conducted in 8 PDCs. Genetic features were evaluated in 9 samples using exomic and transcriptomic sequencing. Results: PDCs exhibited variable sensitivity to mitotane treatment. The median cell viability inhibition rate was 48.4% (IQR: 39.3-59.3%) and -1.2% (IQR: -26.4-22.1%) in responders (n=8) and non-responders (n=9), respectively. Median IC50 and AUC were remarkably lower in responders (IC50: 53.4 µM vs 74.7 µM, P<0.0001; AUC: 158.0 vs 213.5, P<0.0001). Genomic analysis revealed CTNNB1 somatic alterations were only found in responders (3/5) while ZNRF3 alterations only in non-responders (3/4). Transcriptomic profiling found pathways associated with lipid metabolism were upregulated in responder tumors whilst CYP27A1 and ABCA1 expression were positively correlated to in vitro mitotane sensitivity. Furthermore, pharmacologic analysis identified that compounds including disulfiram, niclosamide and bortezomib exhibited efficacy against PDCs. Conclusion: ACC PDCs could be useful for testing drug response, drug repurposing and guiding personalized therapies. Our results suggested response to mitotane might be associated with the dependency on lipid metabolism. CYP27A1 and ABCA1 expression could be predictive markers for mitotane response, and disulfiram, niclosamide and bortezomib could be potential therapeutics, both warranting further investigation.


Asunto(s)
Neoplasias de la Corteza Suprarrenal , Carcinoma Corticosuprarrenal , Antineoplásicos Hormonales , Mitotano , Pruebas de Farmacogenómica , Humanos , Mitotano/uso terapéutico , Carcinoma Corticosuprarrenal/tratamiento farmacológico , Carcinoma Corticosuprarrenal/genética , Carcinoma Corticosuprarrenal/patología , Carcinoma Corticosuprarrenal/metabolismo , Neoplasias de la Corteza Suprarrenal/tratamiento farmacológico , Neoplasias de la Corteza Suprarrenal/genética , Neoplasias de la Corteza Suprarrenal/patología , Neoplasias de la Corteza Suprarrenal/metabolismo , Femenino , Masculino , Antineoplásicos Hormonales/uso terapéutico , Antineoplásicos Hormonales/farmacología , Persona de Mediana Edad , Adulto , Anciano , Farmacogenética
7.
Artículo en Inglés | MEDLINE | ID: mdl-38721992

RESUMEN

OBJECTIVE: Glioblastoma (GBM) is one of the most aggressive brain tumors and often leads to poor outcomes. Studies have indicated that glycan levels are significantly correlated with the pathogenesis and development of cancers. However, whether glycan levels can serve as diagnostic or prognostic biomarkers in GBM remains unclear. METHODS: We obtained glycomic profiles in tissue and serum samples from 55 individuals with GBM using a well-established lectin biochip platform probing with 11 specific lectins. RESULTS: Our univariate analysis showed that 5 out of the 11 lectin-probed glycans (LPGs) were significantly higher in GBM tissues than in peri-tumoral tissues. After logistic regression analyses, only the Jacalin-probed T-antigen difference between the two groups remained significant (p = 0.037). Moreover, survival-related analyses showed that the level of Jacalin-probed T-antigen was significantly associated with the progression-free survival (p = 0.038) of patients. However, none of the LPG levels were correlated with the overall survival or the chemosensitivity to temozolomide therapy. The correlation coefficient analysis showed a moderate-to-strong correlation in the Jacalin-probed T-antigen levels between GBM tissues and serum samples, indicating its potential usefulness as a non-invasive GBM progression biomarker. INTERPRETATION: Glycomics analyses can be helpful in the prediction of GBM recurrences and may provide information useful for GBM glycan-based target therapies or vaccine development.

8.
Small ; : e2402561, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818684

RESUMEN

This review explores the growing interest in 2D layered materials, such as graphene, h-BN, transition metal dichalcogenides (TMDs), and black phosphorus (BP), with a specific focus on recent advances in strain engineering. Both experimental and theoretical results are delved into, highlighting the potential of strain to modulate physical properties, thereby enhancing device performance. Various strain engineering methods are summarized, and the impact of strain on the electrical, optical, magnetic, thermal, and valleytronic properties of 2D materials is thoroughly examined. Finally, the review concludes by addressing potential applications and challenges in utilizing strain engineering for functional devices, offering valuable insights for further research and applications in optoelectronics, thermionics, and spintronics.

9.
Neurol Sci ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38740728

RESUMEN

BACKGROUND: Drug-resistant juvenile myoclonic epilepsy (DR-JME) remains a significant challenge in neurology. Traditional management strategies often fail to achieve satisfactory control, necessitating innovative treatments. OBJECTIVE: This case report aims to evaluate the efficacy and safety of deep brain stimulation (DBS) targeting the subthalamic nucleus (STN-DBS) in a patient with DR-JME. METHODS: We describe the treatment of a patient with DR-JME using STN-DBS. The patient underwent implantation and received high-frequency stimulation (HFS) at the STN. RESULTS: One year post-implantation, the patient demonstrated a substantial reduction in motor seizure frequency by 87.5%, with improvements in quality of life and seizure severity by 52.0% and 46.7%, respectively. No adverse events were reported during the follow-up period. CONCLUSIONS: This case represents the first report of favorable outcomes with STN-DBS in a patient with DR-JME, suggesting that long-term HFS of the STN may be a promising treatment option for patients suffering from this condition.

10.
Bioorg Chem ; 149: 107477, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38820938

RESUMEN

Fms-like tyrosine receptor kinase 3 (FLT3) proteolysis targeting chimeras (PROTACs) emerge as a promising approach to overcome the limitations of FLT3 inhibitors, while the development of orally bioavailable FLT3-PROTACs faces great challenges. Here, we report the rational design and evaluation of a series of Gilteritinib-based FLT3-PROTACs. Among them, B3-2 exhibited the strongest antiproliferative activity against FLT3-ITD mutant AML cells, and significantly induced FLT3-ITD protein degradation. Mechanistic investigations demonstrated that B3-2 induced FLT3-ITD degradation in a ubiquitin-proteasome-dependent manner. More importantly, B3-2 exhibited an oral bioavailability of 5.65%, and oral administration of B3-2 showed good antitumor activity in MV-4-11 xenograft models. Furthermore, B3-2 showed strong antiproliferative activity against FLT3 resistant mutations, highlighting its potential in overcoming drug resistance.

11.
Int J Mol Sci ; 25(10)2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38791547

RESUMEN

The COVID-19 pandemic has made assessing vaccine efficacy more challenging. Besides neutralizing antibody assays, systems vaccinology studies use omics technology to reveal immune response mechanisms and identify gene signatures in human peripheral blood mononuclear cells (PBMCs). However, due to their low proportion in PBMCs, profiling the immune response signatures of dendritic cells (DCs) is difficult. Here, we develop a predictive model for evaluating early immune responses in dendritic cells. We establish a THP-1-derived dendritic cell (TDDC) model and stimulate their maturation in vitro with an optimal dose of attenuated yellow fever 17D (YF-17D). Transcriptomic analysis reveals that type I interferon (IFN-I)-induced immunity plays a key role in dendritic cells. IFN-I regulatory biomarkers (IRF7, SIGLEC1) and IFN-I-inducible biomarkers (IFI27, IFI44, IFIT1, IFIT3, ISG15, MX1, OAS2, OAS3) are identified and validated in vitro and in vivo. Furthermore, we apply this TDDC approach to various types of vaccines, providing novel insights into their early immune response signatures and their heterogeneity in vaccine recipients. Our findings suggest that a standardizable TDDC model is a promising predictive approach to assessing early immunity in DCs. Further research into vaccine efficacy assessment approaches on various types of immune cells could lead to a systemic regimen for vaccine development in the future.


Asunto(s)
Células Dendríticas , Vacunación , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Humanos , Vacunación/métodos , Interferón Tipo I/metabolismo , Interferón Tipo I/inmunología , Células THP-1 , COVID-19/inmunología , COVID-19/prevención & control , Animales , SARS-CoV-2/inmunología , Biomarcadores , Vacunas contra la COVID-19/inmunología , Perfilación de la Expresión Génica , Ratones , Transcriptoma , Vacuna contra la Fiebre Amarilla/inmunología
12.
Int J Biol Macromol ; 270(Pt 1): 132117, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718996

RESUMEN

In this study, cellulose was extracted from black tea residues to produce black tea cellulose nanocrystals (BT-CNCs) using an optimized acid hydrolysis method. The structure and performance of BT-CNCs were evaluated. The results showed that the optimal conditions for acidolysis of BT-CNCs included a sulfuric acid concentration of 64 %, a solid-liquid ratio of 1:18 (w/v), a hydrolysis temperature of 45 °C, and a hydrolysis time of 50 min. The optimization process resulted in a 44.8 % increase in the yield of BT-CNCs, which exhibited a crystallinity of 68.57 % and were characterized by the typical cellulose I structure. The diameters of the particles range from 5 to 45 nm, and they exhibit aggregation behavior. Notably, BT-CNCs demonstrated excellent storage stability, and the Tyndall effect occurred when exposed to a single beam of light. Although the thermal stability of BT-CNCs decreased, their primary thermal degradation temperature remained above 200 °C. The colloidal nature of BT-CNCs was identified as a non-Newtonian fluid with "shear thinning" behavior. This study introduces a novel method to convert tea waste into BT-CNCs, increasing the yield of BT-CNCs and enhancing waste utilization. BT-CNCs hold promise for application in reinforced composites, offering substantial industrial value.


Asunto(s)
Celulosa , Nanopartículas , , Celulosa/química , Té/química , Nanopartículas/química , Hidrólisis , Temperatura , Ácidos Sulfúricos/química
13.
Chem Asian J ; : e202301131, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721778

RESUMEN

A strained triple nanohoop with a shared central benzene unit is synthesized using a threefold intramolecular ring-closing approach. Among the five possible constitutional isomers, the isomer with the highest D3h symmetry is isolated, the structure of which contains three nanohoop blades and a central hexaphenylbenzene unit. The structure is elucidated using NMR spectroscopy and mass spectrometry. The optical and electrochemical properties are investigated, revealing a moderate fluorescence quantum yield of 40%. A water-soluble nanomaterial is prepared using a nanoparticle encapsulation method, and a fluorescence quantum yield of 10% is retained, which demonstrates the potential of the nanomaterial in biological systems.

14.
Small Methods ; : e2301657, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708670

RESUMEN

Memristor possesses great potential and advantages in neuromorphic computing, while consistency and power consumption issues have been hindering its commercialization. Low cost and accuracy are the advantages of human brain, so memristors can be used to construct brain-like synaptic devices to solve these problems. In this work, a five-layer AlOx device with a V-shaped oxygen distribution is used to simulate biological synapses. The device simulates synapse structurally. Further, under electrical stimulation, O2- moves to the Ti electrode and oxygen vacancy (Vo) moves to the Pt electrode, thus forming a conductive filament (CF), which simulates the Ca2+ flow and releases neurotransmitters to the postsynaptic membrane, thus realizing the transmission of information. By controlling applied voltage, the regulation of Ca2+ gated pathway is realized to control the Ca2+ internal flow and achieve different degrees of information transmission. Long-term Potentiation (LTP)/Long-term Depression (LTD), Spike Timing Dependent Plasticity (STDP), these basic synaptic performances can be simulated. The AlOx device realizes low power consumption (56.7 pJ/392 fJ), high switching speed (25 ns/60 ns), and by adjusting the window value, the nonlinearity is improved (0.133/0.084), a high recognition accuracy (98.18%) is obtained in neuromorphic simulation. It shows a great prospect in multi-value storage and neuromorphic computing.

16.
J Hazard Mater ; 471: 134366, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38678708

RESUMEN

The photoexcited dissolved organic matter (DOM) could produce reactive intermediates, affecting chemical oxidant transformation in UV based advanced oxidation processes (AOPs). This study confirmed the critical role of triplet state DOM (3DOM*), generated from DOM photoexcitation, in the transformation of monochloramine (NH2Cl), a commonly used chemical oxidant and disinfectant in water treatment. NH2Cl (42.25 µM, as Cl2) was decayed by 17.4-73.4 % within 60 min, primarily due to 3DOM* , in DOM (2-30 mgC L-1) solutions irradiated by 365 nm, where NH2Cl has no absorption. The second-order quenching rate constants of triplet state model photosensitizers by NH2Cl were determined to be 0.95(± 0.04)-4.49(± 0.04)× 108 M-1 s-1 by using laser flash photolysis. As a reductant, 3DOM* reacted with NH2Cl through one-transfer mechanism, leading to amino radical (NH2•) generation, which then transferred to ammonia (NH4+, pKa 9.25) through H-abstraction by the phenolic moieties in DOM. Additionally, the intermediate product of 3DOM* oxidized by NH2Cl or those triplet state quinones can hydrolyze to form phenolic moieties, elevating NH4+ yield to higher than 99% upon 365 nm irradiation. These findings suggest that the widespread DOM can be applied to convert NH2Cl via 3DOM* with minimal toxic risks.

17.
Chem Biol Interact ; 394: 110987, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38574835

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) are widely used synthetic chemicals that persist in the environment and bioaccumulate in animals and humans. There is growing evidence that PFAS exposure adversely impacts neurodevelopment and neurological health. Steroid 5α-reductase 1 (SRD5A1) plays a key role in neurosteroidogenesis by catalyzing the conversion of testosterone or pregnenolone to neuroactive steroids, which influence neural development, cognition, mood, and behavior. This study investigated the inhibitory strength and binding interactions of 18 PFAS on human and rat SRD5A1 activity using enzyme assays, molecular docking, and structure-activity relationship analysis. Results revealed that C9-C14 PFAS carboxylic acid at 100 µM significantly inhibited human SRD5A1, with IC50 values ranged from 10.99 µM (C11) to 105.01 µM (C14), and only one PFAS sulfonic acid (C8S) significantly inhibited human SRD5A1 activity, with IC50 value of 8.15 µM. For rat SRD5A1, C9-C14 PFAS inhibited rat SRD5A1, showing the similar trend, depending on carbon number of the carbon chain. PFAS inhibit human and rat SRD5A1 in a carbon chain length-dependent manner, with optimal inhibition around C11. Kinetic studies indicated PFAS acted through mixed inhibition. Molecular docking revealed PFAS bind to the domain between NADPH and testosterone binding site of both SRD5A1 enzymes. Inhibitory potency correlated with physicochemical properties like carbon number of the carbon chain. These findings suggest PFAS may disrupt neurosteroid synthesis and provide insight into structure-based inhibition of SRD5A1.


Asunto(s)
3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa , Simulación del Acoplamiento Molecular , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/química , Animales , Humanos , Ratas , Relación Estructura-Actividad , Proteínas de la Membrana/metabolismo , Fluorocarburos/química , Fluorocarburos/metabolismo , Fluorocarburos/farmacología , Unión Proteica , Carbono/química , Carbono/metabolismo , Sitios de Unión
18.
J Am Chem Soc ; 146(15): 10321-10330, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38567901

RESUMEN

Polycyclic hydrocarbons with diradical and polyradical characters usually display unique reactivities in ring-cyclization reactions. However, such reactions are rarely used to construct π-extended polycyclic aromatic hydrocarbons. Here, we describe the synthesis of an S-shaped doubly helical singlet diradicaloid compound and its facile transformation into an unprecedented circumchrysene via a two-stage ring cyclization, which includes: (1) an eletrocylization from diradicaloid precursor and (2) a Scholl reaction. The reaction mechanism was investigated through in situ spectroscopic studies, assisted by theoretical calculations. This reaction sequence yields an optically resolved π-extended [5]helicene derivative with a fluorescence quantum yield up to 85% and a circularly polarized luminescence brightness up to 6.05 M-1 cm-1 in the far-red to near-infrared regions. This sequence also yielded a highly delocalized circumchrysene molecule, exhibiting large electron delocalization, moderate fluorescence quantum yield, and multistage redox properties.

19.
Small ; : e2400570, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38600895

RESUMEN

Lithium (Li) metal batteries are deemed as promising next-generation power solutions but are hindered by the uncontrolled dendrite growth and infinite volume change of Li anodes. The extensively studied 3D scaffolds as solutions generally lead to undesired "top-growth" of Li due to their high electrical conductivity and the lack of ion-transporting pathways. Here, by reducing electrical conductivity and increasing the ionic conductivity of the scaffold, the deposition spot of Li to the bottom of the scaffold can be regulated, thus resulting in a safe bottom-up plating mode of the Li and dendrite-free Li deposition. The resulting symmetrical cells with these scaffolds, despite with a limited pre-plated Li capacity of 5 mAh cm-2, exhibit ultra-stable Li plating/stripping for over 1 year (11 000 h) at a high current density of 3 mA cm-2 and a high areal capacity of 3 mAh cm-2. Moreover, the full cells with these scaffolds further demonstrate high cycling stability under challenging conditions, including high cathode loading of 21.6 mg cm-2, low negative-to-positive ratio of 1.6, and limited electrolyte-to-capacity ratio of 4.2 g Ah-1.

20.
Emerg Med Int ; 2024: 7880345, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38586536

RESUMEN

Background: Emergency department (ED) overcrowding is influenced by several factors including the hospital's capacity, staff, patient discharges, and community resources. The number of annual ED visits has increased, with patients' medical needs exceeding emergency capacity, resulting in a widespread concern about emergency room overcrowding. Nonemergency patients tend to use large amounts of emergency medical resources, which is one reason for ED overcrowding. Most patients consider their medical cases urgent, whereas medical professionals consider many cases to be nonemergency. Only a few studies have examined self-rated health among nonemergency patients. Methods: This cross-sectional study was conducted in the ED of a tertiary hospital in China using the European Quality of Life Five-Dimensional Questionnaire to investigate the health status of nonemergency patients. Results: Among the 545 respondents, 246 (45.14%) self-assessed their health as excellent, 186 (34.13%) as very good, 70 (12.84%) as good, 32 (5.87%) as average, and 11 (2.02%) as poor. Problems related to pain/discomfort were reported by 317 (58.17%) participants, 214 (39.27%) responded that they had problems related to daily activities, 212 (38.90%) responded that they felt anxious or depressed, 211 (38.35%) responded that they had problems related to self-care, and some or extreme problems related to mobility were stated by 193 people (35.41%). Conclusions: Nonemergency patients generally reported good health. Pain/discomfort was the most significant factor affecting the health of nonemergency patients, followed by limitation of daily activities. The duration of illness onset and self-rated health status were common factors influencing the health status of nonemergency patients. This trial is registered with ChiCTR1900023578.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA