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1.
Small ; 20(26): e2311178, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38224219

RESUMEN

Alkaline anion-exchange-membrane water electrolyzers (AEMWEs) using earth-abundant catalysts is a promising approach for the generation of green H2. However, the AEMWEs with alkaline electrolytes suffer from poor performance at high current density compared to proton exchange membrane electrolyzers. Here, atomically dispersed Pt-Ru dual sites co-embedded in nanoporous nickel selenides (np/Pt1Ru1-Ni0.85Se) are developed by a rapid melt-quenching approach to achieve highly-efficient alkaline hydrogen evolution reaction. The np/Pt1Ru1-Ni0.85Se catalyst shows ampere-level current density with a low overpotential (46 mV at 10 mA cm-2 and 225 mV at 1000 mA cm-2), low Tafel slope (32.4 mV dec-1), and excellent long-term durability, significantly outperforming the benchmark Pt/C catalyst and other advanced large-current catalysts. The remarkable HER performance of nanoporous Pt1Ru1-Ni0.85Se is attributed to the strong intracrystal electronic metal-support interaction (IEMSI) between Pt-Se-Ru sites and Ni0.85Se support which can greatly enlarge the charge redistribution density, reduce the energy barrier of water dissociation, and optimize the potential determining step. Furthermore, the assembled alkaline AEMWE with an ultralow Pt and Ru loading realizes an industrial-level current density of 1 A cm-2 at 1.84 volts with high durability.

2.
Apoptosis ; 27(9-10): 751-761, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35759163

RESUMEN

BACKGROUND: The present study is to investigate the biological functions and mechanisms of circular RNA_0000523 (circ_0000523) in nasopharyngeal carcinoma (NPC). METHODS: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was conducted to examine the expression levels of circ_0000523 and microRNA-1184 (miR-1184) in NPC tissues and cells. Collagen type 1 alpha 1 chain (COL1A1) expression was assessed by qRT-PCR and immunohistochemistry (IHC) assay. Cell proliferation, cell cycle progression, migration and invasion were examined by cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU), flow cytometry and Transwell assays. Xenograft nude mouse models were used to investigate the metastatic potential of NPC cells in vivo. The binding relationships between circ_0000523 and miR-1184, and between miR-1184 and COL1A1 were detected by dual-luciferase reporter gene assay. The protein expressions of COL1A1, phosphatidylinositol 3-kinase (p85), phosphorylated (p)-p85, protein kinase B (Akt) and p-Akt were detected through Western blot. The DAVID database was used for the enrichment analysis of the potential targets of miR-1184. RESULTS: Circ_0000523 and COL1A1 mRNA expressions were significantly increased in NPC tissues and cell lines. Circ_0000523 overexpression promoted NPC cell proliferation and accelerated cell cycle progression, whereas miR-1184 overexpression reversed these effects; circ_0000523 knockdown suppressed NPC cell proliferation and induced cell cycle arrest, while miR-1184 inhibition counteracted these effects. MiR-1184 was the downstream target of circ_0000523, and COL1A1 was the target gene of miR-1184 and could be positively modulated by circ_0000523. COL1A1 overexpression increased the expression levels of p-p85 and p-Akt, whereas knocking down COL1A1 repressed their expressions. CONCLUSIONS: Circ_0000523 facilitates NPC progression through regulating the miR-1184/COL1A1 axis.


Asunto(s)
MicroARNs , Neoplasias Nasofaríngeas , Animales , Apoptosis/fisiología , Bromodesoxiuridina , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Colágeno/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Circular/genética , ARN Mensajero
3.
Small ; 17(12): e2007389, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33656244

RESUMEN

Miniaturized energy storage devices (MESDs) provide future solutions for powering dispersive electronics and small devices. Among them, aqueous zinc ion microbatteries (ZIMBs) are a type of promising MESDs because of their high-capacity Zn anode, safe and green aqueous electrolytes, and good battery performances. Herein, for the first time, a simple and powerful strategy to fabricate flexible ZIMBs based on tailored soft templates is reported, which are patterned by engraving and enables to design the ZIMBs featured with arbitrary shapes and on various substrates. The assembled ZIMBs employing α-MnS as the cathode materials and guar gum gel as the quasi-solid-state electrolyte exhibited very high areal specific capacity of up to 178 µAh cm-2 , a notable areal energy density of 322 µWh cm-2 and power density of 710 µW cm-2 . Footprint areas of the manufactured ZIMBs as small as 40 mm2 can be achieved. The proposed method based on the engraved soft templates provides a practical route for ZIMB and other MESD designs, which is critical for portable and wearable electronics development.

4.
Nanotechnology ; 32(50)2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34525467

RESUMEN

Due to magnetic field tunability and the abundance of iron in the Earth's crust, iron oxide-based resistive random access memory (RRAM) is considered to be low cost and potential for multi-level storage. However, the relatively high operation voltage (>1 V) and small storage window (<100) limit its application. In this work, the devices with simple Ag/Fe2O3/Pt structure exhibit typical bipolar resistive switching with ultralow set voltage (Vset) of 0.16 V, ultralow reset voltage (Vreset) of -0.04 V, high OFF/ON resistance ratio of 103, excellent cycling endurance more than 104and good retention time longer than 104s. Each major parameter has about an order of magnitude improvement compared to the previous data. The devices demonstrate outstanding stable low power consumption quality. Based on the analysis of the experimental results, a percolation model of silver ion migration was established and confirmed that low operation voltage is attributed to the amorphous oxide layer with large porosity. During electrical testing, the compliance current (Ic) and maximum reset voltage (Vmax) can also affect the device performance. This discovery suggests Fe2O3memristor has significant potential for application and provides a new idea for the realization of high-performance low-power RRAM.

5.
Int J Clin Pharmacol Ther ; 59(7): 496-505, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33960299

RESUMEN

OBJECTIVE: This paper aims to assess the efficacy of tigecycline in the treatment of several different infections from a pharmacokinetic/pharmacodynamic (PK/PD) perspective. MATERIALS AND METHODS: The minimum inhibitory concentration (MIC) test strip test was used to determine the MICs of clinical isolates of tigecycline. A 5,000-subjects simulation was performed by Crystal Ball software to calculate the probability of achieving the required PK/PD exposure. RESULTS: The use of standard tigecycline dosing is predicted to have a good clinical outcome for patients suffering from complicated skin and skin structure infection (cSSSI) with MICs ≤ 0.25 mg×L-1, patients suffering from complicated intra-abdominal infection (cIAI) with MICs ≤ 1 mg×L-1, and patients suffering from hospital-acquired pneumonia (HAP) with MICs ≤ 0.5 mg×L-1. Generally, Gram-positive bacteria are highly sensitive to tigecycline, while Gram-negative bacteria are less sensitive: for patients with HAP and cIAI, the tolerable outcome was achieved using the standard regimen for most Gram-negative pathogens; the desired outcomes could be obtained for the increased-dose treatment; with increasing dose (100 mg every 12 hours), the average cumulative fractions of response (CFRs) markedly increased from 38.18 to 56.21% for cSSSI patients. When tigecycline, a standard regimen, was used to treat carbapenem-resistant Klebsiella pneumoniae (CRKP) and carbapenem-resistant Enterobacter spp. (CRE) infections, the cumulative response scores were 4.96 - 66.39% and 13.14 - 95.18%, respectively, and the CFRs of the increased dose also increased correspondingly. CONCLUSION: Currently, the standard dose of tigecycline is feasible in the treatment of common bacterial infections, and PK/PD indexes are needed to optimize the regimens for refractory carbapenem-resistant bacterial infections.


Asunto(s)
Antibacterianos , Minociclina , Antibacterianos/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana , Método de Montecarlo , Tigeciclina
6.
Ther Drug Monit ; 42(6): 835-840, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32858577

RESUMEN

OBJECTIVE: Tigecycline exerts significant beneficial effects against drug-resistant bacterial infections. The largely empirical medications used in clinical practice are often associated with wide individual differences in efficacy and safety. We investigated the associations between the pharmacokinetics of tigecycline and its efficacy and safety in intensive care unit (ICU) patients, with the aim of facilitating clinical applications of tigecycline. METHODS: ICU patients who were prescribed tigecycline in a hospital setting were prospectively included. Factors related to the clinical efficacy and safety of tigecycline were assessed by univariate and multivariate analyses. RESULTS: This study included 45 patients, from whom a total of 63 blood samples were collected to determine steady-state trough plasma concentrations (Cmin) of tigecycline. The Cmin of tigecycline was 417.1 ± 263.8 ng/mL (mean ± SD). The multivariate analysis showed that the APACHE II scores [odds ratio (OR) = 0.874, 95% confidence interval (CI) = 0.733-0.901, P = 0.048] were significantly correlated with the efficacy of tigecycline, whereas there was no correlation between Cmin of tigecycline and efficacy. In safety, the risk factors significantly associated with hepatotoxicity were sex (OR = 0.562, 95% CI = 0.191-0.774, P = 0.023), APACHE II score (OR = 1.061, 95% CI = 1.039-1.392, P = 0.045), and Cmin (OR = 1.210, 95% CI = 1.014-1.336, P = 0.008). The optimal cut-off for hepatotoxicity in ICU patients treated with tigecycline was 474.8 ng/mL. CONCLUSIONS: There was considerable variability in the Cmin of tigecycline among the ICU patients in this study and it is at risk of high exposure in women. Cmin can be a useful predictor of hepatotoxicity with a cut-off of 474.8 ng/mL.


Asunto(s)
Antibacterianos , Monitoreo de Drogas , Tigeciclina , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Cuidados Críticos , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Tigeciclina/administración & dosificación , Tigeciclina/efectos adversos
7.
BMC Nephrol ; 21(1): 335, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32778065

RESUMEN

BACKGROUND: Renal artery aneurysms (RAAs) are rare and usually asymptomatic, and some RAAs can be associated with calcifications, which may lead to misdiagnoses as renal calculi, which are then mistakenly treated. CASE PRESENTATION: A 69-year-old female patient was admitted to the hospital with no discomfort and was diagnosed with a large right renal calculus. The ultrasound and computed tomography urography (CTU) scan suggested a large calculus in the right pelvis with hydrops of the kidney. Therefore, we chose percutaneous nephrolithotomy (PCNL) to treat the right renal calculus, but no calculi were found in the renal pelvis. When we removed the mucosa of the renal pelvis with a holmium laser, we observed a fluctuating unruptured aneurysm with calcification. Therefore, the previous diagnosis of a renal calculus was disregarded. The operation was stopped immediately, and then computed tomography (CT) angiography was performed, confirming the right renal aneurysm with calcification. Then, Renal artery aneurysm (RAA) coil embolization was performed. After a long-term follow-up, the patient recovered well. CONCLUSIONS: The RAA of this patient had calcific changes, which led us to errors in the diagnosis. Hence, it is very important for surgeons to effectively distinguish between renal calculi and aneurysms with ring-like calcifications. Our case report looks back at the thrilling situation during the operation and advises surgeons on how to deal with this situation properly.


Asunto(s)
Aneurisma/diagnóstico , Errores Diagnósticos , Cálculos Renales/diagnóstico , Pelvis Renal/diagnóstico por imagen , Nefrolitotomía Percutánea , Arteria Renal/diagnóstico por imagen , Calcificación Vascular/diagnóstico , Anciano , Aneurisma/terapia , Angiografía por Tomografía Computarizada , Embolización Terapéutica , Femenino , Humanos , Pelvis Renal/cirugía , Radiografía Abdominal , Tomografía Computarizada por Rayos X , Ultrasonografía , Calcificación Vascular/terapia
8.
Sensors (Basel) ; 20(17)2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32872290

RESUMEN

This paper presents a passive wireless long-range displacement sensor that is based on the circular patch antenna, and the detecting range of the sensor can be customized. The sensor consists of a chipped circular antenna with two opened rectangular windows, a substrate, and a ground plate with a sloping channel. No bonding between the antenna and the ground plate allows for the chipped antenna to slide along the sloping channel. The channel will drive the current flow on the plate once the chip is activated, increasing the effective electrical length and, consequently, decreasing the resonant frequency of the circular antenna. The sensing mechanism equates the measuring displacement to the relative movement of the antenna with respect to the ground that achieves the measurement of long-range displacement and, thus, the proposed sensor can avoid stress damage to the antenna due to excessive deformation. Three different range sensors were simulated in the the Ansoft high frequency structure simulator (HFSS). The results show that the resonance frequency of the antenna has a linear relationship with the varying chute depth beneath the chip. Three sensors were fabricated, and the experimental results also validated that the sensitivity of the sensor can be adjusted.

9.
Opt Express ; 26(3): 2380-2389, 2018 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-29401778

RESUMEN

We combined confocal surface plasmon coupled emission microscopy (C-SPCEM) together with fluorescence emission difference (FED) technique to pursuit super-resolution fluorescent image. Solid or hollow point spread function (PSF) for C-SPCEM is achieved with radially-polarized or circularly-polarized illumination. The reason why PSF can be manipulated by the polarization of illumination light is corroborated by the interaction of fluorescent emitter with vector focal field on the plasmonic substrate. After introduction of FED technique, PSF for C-SPECM can shrunk to around λ/4 in full-width half-maximum, which is unambiguously beyond Rayleigh's diffraction limit. The super-resolution capability of C-SPCEM with FED technique is experimentally demonstrated by imaging aggregated fluorescent beads with 150 nm in diameter.

10.
Nanotechnology ; 28(38): 385401, 2017 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-28628485

RESUMEN

Large-area ordered arrays with dense hotspots are highly desirable substrates for surface enhanced Raman scattering (SERS). In this paper, we present a quasi-3D SERS substrate of free-standing Ag triangle arrays (FATA) which was fabricated by nanosphere lithography incorporated with photolithography and Ag covering. A significant SERS effect arises from a strongly enhanced local electric field within the tiny gaps between the suspended Ag triangle and the Ag baseplate. The SERS intensity relative standard deviation is less than 7.6%, leading to excellent reliability for Raman detection. The simple fabrication of the Ag film covering FATA nanostructures provides a practical solution for large-area, highly efficient and reproducible SERS substrates.

11.
Acta Pharmacol Sin ; 38(2): 211-222, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27890916

RESUMEN

Recent studies show that Polydatin (PD) extracted from the roots of Polygonum cuspidatum Sieb, a widely used traditional Chinese remedies, possesses anti-inflammatory activity in several experimental models. In this study, we investigated the anti-inflammatory effects of PD on Staphylococcus aureus-induced mastitis in mice and elucidated the potential mechanisms. In mice with S aureus-induced mastitis, administration of PD (15, 30, 45 mg/kg, ip) or dexamethasone (Dex, 5 mg/kg, ip) significantly suppressed the infiltration of inflammatory cells, ameliorated the mammary structural damage, and inhibited the activity of myeloperoxidase, a biomarker of neutrophils accumulation. Furthermore, PD treatment dose-dependently decreased the levels of TNF-α, IL-1ß, IL-6 and IL-8 in the mammary gland tissues. PD treatment also dose-dependently decreased the expression of TLR2, MyD88, IRAK1, IRAK4 and TRAF6 as well as the phosphorylation of TAK1, MKK3/6, p38 MAPK, IκB-α and NF-κB in the mammary gland tissues. In mouse mammary epithelial cells (mMECs) infected by S aureus in vitro, pretreatment with PD dose-dependently suppressed the upregulated pro-inflammatory cytokines and signaling proteins, and the nuclear translocation of NF-κB p65 and AP-1. A TLR2-neutralizing antibody mimicked PD in its suppression on S aureus-induced upregulation of MyD88, p-p38 and p-p65 levels in mMECs. PD (50, 100 µg/mL) affected neither the growth of S aureus in vitro, nor the viability of mMECs. In conclusion, PD does not exhibit antibacterial activity against S aureus, its therapeutic effects in mouse S aureus-induced mastitis depend on its ability to down-regulate pro-inflammatory cytokine levels via inhibiting TLR2-mediated activation of the p38 MAPK/NF-κB signaling pathway.


Asunto(s)
Glucósidos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Mastitis/tratamiento farmacológico , FN-kappa B/metabolismo , Staphylococcus aureus/efectos de los fármacos , Estilbenos/farmacología , Receptor Toll-Like 2/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Antiinflamatorios/farmacología , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Dexametasona/farmacología , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Femenino , Mediadores de Inflamación/metabolismo , Mastitis/inmunología , Mastitis/metabolismo , Mastitis/microbiología , Ratones , Infiltración Neutrófila/efectos de los fármacos , Peroxidasa/antagonistas & inhibidores , Staphylococcus aureus/inmunología , Receptor Toll-Like 2/inmunología
12.
Zhonghua Nan Ke Xue ; 23(10): 883-888, 2017 Oct.
Artículo en Zh | MEDLINE | ID: mdl-29727536

RESUMEN

OBJECTIVE: To explore the factors influencing the sexual function of the male patients with obstructive sleep apnea (OSA). METHODS: Using Arizona Sexual Experience Scale (ASEX) and Epworth Sleepiness Scale (ESS), we conducted a questionnaire investigation among 81 male patients with OSA aged 40.5 ± 8.6 years and 35 healthy volunteers aged 38.8 ± 10 years. According to the sex drive (SD) score in ASEX, we divided the OSA patients into an SD reduction group (SD score = 4, n = 32) and a non-SD reduction group (SD score <4, n = 49), compared the clinical data and polysomnographic (PSG) indexes, and analyzed the factors influencing SD by evaluating the association of the PSG indexes with the SD score. RESULTS: The OSA patients scored significantly higher than the healthy controls in ESS (8 ± 5 vs 5 ± 4, P <0.05) and ASEX (15 ± 4 vs 10 ± 2, P <0.05), and so did the patients of the SD reduction group than those of the non-SD reduction group in ESS (9 ± 5 vs 6 ± 5, P <0.05) and saturation impair time below 90% (SIT90) (41.01 ± 26.95 vs 21.87 ± 19.03, P <0.05). Multivariate regression analysis revealed that the SD score was significantly correlated with age (ß = 0.25, P <0.001) and SIT90 (ß = 0.4, P <0.001) in the OSA patients. CONCLUSIONS: OSA affects various aspects of the sexual function, particularly SD, of the patient. The duration of hypoxia and age of the patient are independent risk factors for SD reduction, which can be considered as a main clinical symptom of OSA.


Asunto(s)
Libido/fisiología , Apnea Obstructiva del Sueño/complicaciones , Adulto , Factores de Edad , Estudios de Casos y Controles , Humanos , Hipoxia/complicaciones , Masculino , Factores de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo
13.
Nanotechnology ; 27(49): 495402, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27827351

RESUMEN

Vertically coupled plasmonic structure is of great interest for surface-enhanced Raman scattering (SERS). In this paper, a large-area reproducible SERS substrate is fabricated and demonstrated by a vertically coupled structure composed of Ag triangle arrays on Ag films separated by a nanometric dielectric layer. This metal-insulator-metal (MIM) nanostructure has broadband resonance covering both the laser excitation and Stokes frequencies. Thanks to the convenience of controlling the gap distance by thin dielectric film, the SERS substrate is optimized to yield the best enhancement. The SERS enhancement factor is estimated to be 5.8 × 106 for on-resonant pumping with a 532 nm laser. The uniformity and reproducibility of the SERS substrate are also demonstrated. Our results pave the way for rational design of sensitive SERS substrates and harmless exciting SERS signals.

14.
Nanotechnology ; 27(16): 165401, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-26939539

RESUMEN

Enhanced electromagnetic field in the tiny gaps between metallic nanostructures holds great promise in optical applications. Herein, we report novel out-of-plane nanogaps composed of micrometer-sized Ag triangular nanoplates (AgTN) on Ag films. Notably, the new coupled plasmonic structure can dramatically enhance the surface-enhanced Raman scattering (SERS) by visible laser excitation, although the micrometer-sized AgTN has localized plasmon resonance at infrared wavelength. This enhancement is derived from the gap plasmon polariton between the AgTN and Ag film, which is excited via the antenna effect of the corner and edge of the AgTN. Systematic SERS studies indicated that the plasmon enhancement was on the order of corner > edge > face. These results were further verified by theoretical simulations. Our device paves the way for rational design of sensitive SERS substrates by judiciously choosing appropriate nanoparticles and optimizing the gap distance.

15.
Nanotechnology ; 27(41): 415708, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27607837

RESUMEN

Plasmonic resonant cavities are capable of confining light at the nanoscale, resulting in both enhanced local electromagnetic fields and lower mode volumes. However, conventional plasmonic resonant cavities possess large Ohmic losses at metal-dielectric interfaces. Plasmonic near-field coupling plays a key role in a design of photonic components based on the resonant cavities because of the possibility to reduce losses. Here, we study the plasmonic near-field coupling in the silver nanorod metamaterials treated as resonant nanostructured optical cavities. Reflectance measurements reveal the existence of multiple resonance modes of the nanorod metamaterials, which is consistent with our theoretical analysis. Furthermore, our numerical simulations show that the electric field at the longitudinal resonances forms standing waves in the nanocavities due to the near-field coupling between the adjacent nanorods, and a new hybrid mode emerges due to a coupling between nanorods and a gold-film substrate. We demonstrate that this coupling can be controlled by changing the gap between the silver nanorod array and gold substrate.

16.
Opt Lett ; 39(16): 4707-10, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25121854

RESUMEN

We report a propagation spectrum detection system in which one end of a plasmonic silver nanowire is locally illuminated from a normal halogen lamp and the scattered light is recorded spectroscopically at the other end. The system is applied to investigate surface plasmon polariton-Fabry-Perot (SPP-FP) modes of silver nanowires with different lengths at air-glass and oil-glass interfaces. The generalized FP model is used to analyze the spectrum, which fits well with the experimental results. The influence of nanowire length and environment on the properties of the FP resonances is discussed. The propagation spectrum detection system will find applications for integrated optical circuits and plasmonic sensing.

17.
ACS Appl Mater Interfaces ; 16(1): 342-352, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38111104

RESUMEN

Covalent organic frameworks (COFs) have emerged as promising drug carriers due to their structural variability, inherent porosity, and customizable functions. However, most COFs used in drug delivery suffer from low cellular bioavailability and poor luminescence properties. In this study, we designed a series of size-tunable, crystalline, and red-fluorescent COF nanospheres (COFNSs) for trackable anticancer drug delivery. The semiconducting COFNSs were prepared by condensations of 1,3,5-triformylbenzene (TFB) with various dihydrazide blocks through the Schiff-base reaction, resulting in red emission at 647 nm and excellent fluorescence stability (∼100% for 1 h). Such fluorescence property allowed for systematic investigation of the cellular endocytosis pathway of COFNSs, visualization of drug delivery, and observation of the cell apoptosis process. The COFNSs exhibited high cell viability (>90%), a loading capacity of 183 wt % for the anticancer drug camptothecin (CPT), and significant enhancement in inhibiting 4T1 cancers both in vitro and in vivo as the CPT nanocarrier. This progress presents a valuable approach to design COF nanocarriers with integrated fluorescent and drug delivery functions.


Asunto(s)
Estructuras Metalorgánicas , Nanosferas , Sistemas de Liberación de Medicamentos , Portadores de Fármacos , Apoptosis , Colorantes
18.
Bot Stud ; 65(1): 12, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38679692

RESUMEN

BACKGROUND: Accurate species delimitation is fundamental for testing evolutionary theory and provides essential implications for conservation management. The arctic-alpine genus Saxifraga L. (Saxifragaceae) is taxonomically complex and many species have not been critically assessed. The taxonomic and phylogenetic status of Saxifraga lancangensis Y.Y.Qian, considered as a synonym of Saxifraga mengtzeana Engl. & Irmsch. in previous studies, is re-evaluated in light of new evidence presented here. RESULTS: Evidence from morphological comparison and sequencing of plastid genome indicate that S. lancangensis belongs to Saxifraga sect. Irregulares Haw., and is closely related to Saxifraga geifolia Balf.f., and S. mengtzeana. However, S. lancangensis can be diagnosed by its petals with red and clawless base, leaf blade orbicular and leaf margin shallowly dentate. CONCLUSIONS: The morphological and molecular evidence support the resurrection of S. lancangensis as a distinct species. An updated morphological description based on protologue and fresh material, diagnostic characters, and original photographs of the resurrected species are presented.

19.
Heliyon ; 10(7): e28497, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38689980

RESUMEN

Background: While hepatocellular carcinoma (HCC) represents a highly heterogeneous disease with variable oncogenesis mechanisms and biological features, little is understood about differences in distant metastasis (DM) and prognosis between early-onset and late-onset HCC. This study defined early-onset disease as cancer diagnosed at age younger than 50 years and aimed to present a comprehensive analysis to characterize these disparities based on age. Methods: Information of HCC patients was retrospectively collected from the SEER database and our hospital. Patient demographics, tumor characteristics, and survival were compared between the two groups. A 1:1 propensity score matching (PSM) was adopted to adjust confounding factors. Logistic and cox analysis were utilized to explore risk factors of DM and prognosis, respectively. Besides, the survival differences were assessed by the Kaplan-Meier curve and log-rank test. Results: In total, 19187 HCC patients obtained from the SEER database and 129 HCC patients obtained from our own center were enrolled. Among 19187 patients with HCC, 3376 were identified in the matched cohort, including 1688 early-onset patients and 1688 late-onset patients. Compared with late-onset HCC, early-onset HCC was more likely to occur in female (25.2% vs. 22.9%, P = 0.030), have large tumors (>10.0 cm, 24.1% vs. 14.6%, P = 0.000), harbor poorly differentiated/undifferentiated cancers (17.0% vs. 14.0%, P = 0.003), present advanced clinical stage (T3+T4, 33.7% vs. 28.5%; N1, 9.2% vs. 6.7%; P = 0.000), and develop DM (13.0% vs. 9.5%, P = 0.000). After adjustment for confounders by PSM, we discovered that early-onset HCC remained an independent risk factor for DM. However, combined with Kaplan-Meier curve and cox analysis, early-onset HCC was an independent favorable predictor of survival. We validated these data on an independent cohort from our hospital. Conclusion: In this population-based study, despite developing DM more frequently, early-onset HCC exhibited a superior prognosis than late-onset HCC. Nevertheless, further research is warranted to understand the underlying aetiologic basis for the disparities.

20.
Sci Total Environ ; 916: 170098, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38278250

RESUMEN

Soil moisture (SM) directly controls the land surface energy partition which plays an important role in the formation of extreme weather events. However, its dependence on specific climatic conditions is not thoroughly understood due to the complexity of soil moisture effects. Here, we examine the relationship between SM and surface energy partitioning under different climate conditions, and identify the influence paradigms of soil moisture on surface energy partition. We find that temperature changes can explicitly determine the impact paradigm of different physical processes, i.e. evapotranspiration, soil freezing and thawing, and such influence paradigms are also affected by atmospheric aridity (VPD). Globally, there are five paradigms that effects on surface energy partitioning, including the warm-wet paradigm (WW), transitional paradigm (TP), warm-dry paradigm (WD), cool-wet paradigm (CW) and cold paradigm (CP). Since 1981, the global area proportion for TP is observed to increase pronouncedly. We also find that the critical SM threshold exhibits regional variations and the global average is 0.45 m3/m3. The identified paradigms and their long-term change trends provide new insights into the global intensification of land-atmosphere interaction, which has important implications for global warming and the formation of heatwaves.

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