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1.
Small ; 20(30): e2310276, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38431964

RESUMEN

Violet phosphorus (VP) has attracted a lot of attention for its unique physicochemical properties and emerging potential in photoelectronic applications. Although VP has a van der Waals (vdW) structure similar to that of other 2D semiconductors, direct synthesis of VP on a substrate is still challenging. Moreover, optoelectronic devices composed of transfer-free VP flakes have not been demonstrated. Herein, a bismuth-assisted vapor phase transport technique is designed to grow uniform single-crystal VP flakes on the SiO2/Si substrate directly. The size of the crystalline VP flakes is an order of magnitude larger than that of previous liquid-exfoliated samples. The photodetector fabricated with the VP flakes shows a high responsivity of 12.5 A W-1 and response/recovery time of 3.82/3.03 ms upon exposure to 532 nm light. Furthermore, the photodetector shows a small dark current (<1 pA) that is beneficial to high-sensitivity photodetection. As a result, the detectivity is 1.38 × 1013 Jones that is comparable with that of the vdW p-n heterojunction detector. The results reveal the great potential of VP in optoelectronic devices as well as the CVT technique for the growth of single-crystal semiconductor thin films.

2.
J Pharmacol Exp Ther ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849141

RESUMEN

Triple-negative breast cancer (TNBC) is characterized by high mortality rates primarily due to its propensity for metastasis. Addressing this challenge necessitates the development of effective antimetastatic therapies. This study aimed to identify natural compounds with potential antimetastatic properties mainly based on the high-throughput phenotypic screening system. This system, utilizing luciferase reporter gene assays combined with scratch wound assays, evaluates compounds based on their influence on the epithelial-mesenchymal transition (EMT) marker E-cadherin. Through this approach, aurovertin B (AVB) was revealed to have significant antimetastatic capability. Notably, AVB exhibited substantial metastasis suppression in many TNBC cell lines, including MDA-MB-231, HCC1937 and 4T1. Also, its remarkable antimetastatic activity was demonstrated in vivo via the orthotopic breast cancer mouse model. Further exploration revealed a pronounced association between AVB-induced upregulation of DUSP1 (dual-specificity phosphatase 1) and its inhibitory effect on TNBC metastasis. Additionally, microarray analysis conducted to elucidate the underlying mechanism of the AVB-DUSP1 interaction identified ATF3 (activating transcription factor 3) as a critical transcription factor instrumental in DUSP1 transcriptional activation. This discovery, coupled with observations of enhanced ATF3-DUSP1 expression and consequent reduction in TNBC metastatic foci in response to AVB, provides novel insights into the molecular mechanisms driving metastasis in TNBC. Significance Statement We construct a high-throughput phenotypic screening system utilizing EMT marker E-cadherin promoter luciferase reporter gene combined with scratch wound assays. Aurovertin B was revealed to possess significant antimetastatic activity through this approach, which was further demonstrated via in vivo and in vitro experiments. The discovery of the regulatory role of the ATF3-DUSP1 pathway enriches our understanding of TNBC metastasis mechanism and suggests the potential of ATF3 and DUSP1 as biomarkers for diagnosing TNBC metastasis.

3.
Glob Chang Biol ; 30(1): e17016, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37921358

RESUMEN

Carbon allocation has been fundamental for long-lived trees to survive cold stress at their upper elevation range limit. Although carbon allocation between non-structural carbohydrate (NSC) storage and structural growth is well-documented, it still remains unclear how ongoing climate warming influences these processes, particularly whether these two processes will shift in parallel or respond divergently to warming. Using a combination of an in situ downward-transplant warming experiment and an ex situ chamber warming treatment, we investigated how subalpine fir trees at their upper elevation limit coordinated carbon allocation priority among different sinks (e.g., NSC storage and structural growth) at whole-tree level in response to elevated temperature. We found that transplanted individuals from the upper elevation limit to lower elevations generally induced an increase in specific leaf area, but there was no detected evidence of warming effect on leaf-level saturated photosynthetic rates. Additionally, our results challenged the expectation that climate warming will accelerate structural carbon accumulation while maintaining NSC constant. Instead, individuals favored allocating available carbon to NSC storage over structural growth after 1 year of warming, despite the amplification in total biomass encouraged by both in situ and ex situ experimental warming. Unexpectedly, continued warming drove a regime shift in carbon allocation priority, which was manifested in the increase of NSC storage in synchrony to structural growth enhancement. These findings imply that climate warming would release trees at their cold edge from C-conservative allocation strategy of storage over structural growth. Thus, understanding the strategical regulation of the carbon allocation priority and the distinctive function of carbon sink components is of great implication for predicting tree fate in the future climate warming.


Asunto(s)
Abies , Árboles , Humanos , Clima , Fotosíntesis , Carbono
4.
Opt Lett ; 49(13): 3600-3603, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950219

RESUMEN

Visualizing a 3D blood flow velocity field through noninvasive imaging is crucial for analyzing hemodynamic mechanisms in areas prone to disorders. However, traditional correlation-based optical coherence tomography (OCT) velocimetry techniques have a maximum measurable flow velocity depending on the A-line rate. We presented the ergodic speckle contrast OCT (ESCOCT) to break the bottleneck in measuring the rapid blood flow velocity. It achieved a measurement of blood flow velocity ranging from 9.5 to 280 mm/s using a 100 kHz swept-source (SS) OCT based on 100 A-repeats scanning mode. Addressing the non-ergodic problem of temporal OCT signals by integrating more consecutive A-scans, ESCOCT can enable the estimation for lower velocity flows by increasing A-repeats. ESCOCT provided a wide dynamic range with no upper limit on measuring blood flow velocity with an adequate signal-to-noise ratio and improved the sensitivity and accuracy of the hemodynamic assessment.


Asunto(s)
Tomografía de Coherencia Óptica , Tomografía de Coherencia Óptica/métodos , Velocidad del Flujo Sanguíneo/fisiología , Reología/métodos , Humanos , Relación Señal-Ruido
5.
Retina ; 44(6): 1015-1020, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38295391

RESUMEN

PURPOSE: To report the long-term clinical outcomes of transscleral four-point fixation of Akreos intraocular lens using a closed continuous-loop suture technique. METHODS: This was a retrospective, multicenter, interventional case series. Primary outcome measures were best-corrected visual acuity, intraocular pressure, corneal endothelial cell density, and complications with a minimum of 1-year follow-up. RESULTS: One hundred and ninety-two eyes of 177 patients from two surgical hospital sites were identified. The mean best-corrected visual acuity improved from 0.88 ± 0.74 logarithm of the minimum angle of resolution (Snellen 20/152) preoperatively to 0.42 ± 0.52 logarithm of the minimum angle of resolution (Snellen 20/53) postoperatively ( P < 0.001). The mean preoperative intraocular pressure was 17.51 ± 8.67 mmHg, and the mean postoperative intraocular pressure at final follow-up was 15.08 ± 4.18 mmHg ( P = 0.001). The mean corneal endothelial cell density significantly reduced from 2,259 ± 729 cells/mm 2 to 2077 ± 659 cells/mm 2 , representing a cell loss of 5.73% ( P < 0.001). The intraocular lens was fixed well during follow-up. There were no intraoperative complications noted. Postoperative complications included transient ocular hypertension in 15 eyes (7.81%), hypotony in two eyes (1.04%), retinal detachment in one eye (0.52%), and macular edema in one eye (0.52%). CONCLUSION: The transscleral four-point fixation Akreos intraocular lens using the closed continuous-loop suture technique was effective and safe with satisfactory visual acuity with a minimum of 1-year follow-up.


Asunto(s)
Presión Intraocular , Implantación de Lentes Intraoculares , Esclerótica , Técnicas de Sutura , Agudeza Visual , Humanos , Estudios Retrospectivos , Masculino , Femenino , Agudeza Visual/fisiología , Esclerótica/cirugía , Implantación de Lentes Intraoculares/métodos , Anciano , Persona de Mediana Edad , Estudios de Seguimiento , Presión Intraocular/fisiología , Lentes Intraoculares , Adulto , Anciano de 80 o más Años , Resultado del Tratamiento , Endotelio Corneal/patología , Recuento de Células , Diseño de Prótesis , Factores de Tiempo , Suturas , Complicaciones Posoperatorias
6.
Ecotoxicol Environ Saf ; 277: 116359, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38663194

RESUMEN

2,6-Dihalogenated nitrophenols (2,6-DHNPs) are emerging halogenated nitroaromatic pollutants that have been detected in various water environments. However, there is currently limited research available regarding their potential impacts on locomotion behavior and neurotoxicity. Therefore, this study utilized zebrafish embryos to investigate the potential neurotoxic effects of 2,6-DHNPs by examining their impact on the nervous system at a concentration defined as 10% of the median lethal concentration. Our findings demonstrated that exposure to 2,6-DHNPs resulted in a significant 30 % decrease in the total swimming distance of zebrafish larvae, accompanied by notable impairments in motor neuron development and central nervous system. These effects were evidenced by a substantial 25% decrease in axonal growth, as well as disruptions in synapse formation and neuronal differentiation. Additionally, neurotransmitter analysis revealed marked decreases of 40%, 35%, and 30% in dopamine, 5-hydroxytryptamine, and acetylcholine levels respectively, highlighting disturbances in their synthesis, transport, and degradation mechanisms. These results emphasize the considerable neurotoxicity of 2,6-DHNPs at concentrations previously considered safe; thus necessitating a re-evaluation of environmental risk assessments and regulatory standards for such emerging contaminants.


Asunto(s)
Embrión no Mamífero , Contaminantes Químicos del Agua , Pez Cebra , Animales , Contaminantes Químicos del Agua/toxicidad , Embrión no Mamífero/efectos de los fármacos , Síndromes de Neurotoxicidad/etiología , Neuronas Motoras/efectos de los fármacos , Natación , Neurotransmisores/metabolismo , Larva/efectos de los fármacos
7.
Int J Mol Sci ; 25(14)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39062800

RESUMEN

Transient ischemic attack (TIA) is an early warning sign of stroke and death, necessitating suitable animal models due to the associated clinical diagnostic challenges. In this study, we developed a TIA model using flexible spatially targeted photothrombosis combined with real-time blood flow imaging feedback. By modulating the excitation light using wavefront technology, we precisely created a square light spot (50 × 250 µm), targeted at the distal middle cerebral artery (dMCA). The use of laser speckle contrast imaging (LSCI) provided real-time feedback on the ischemia, while the excitation light was ceased upon reaching complete occlusion. Our results demonstrated that the photothrombus formed in the dMCA and spontaneously recanalized within 10 min (416.8 ± 96.4 s), with no sensorimotor deficits or infarction 24 h post-TIA. During the acute phase, ischemic spreading depression occurred in the ipsilateral dorsal cortex, leading to more severe ischemia and collateral circulation establishment synchronized with the onset of dMCA narrowing. Post-reperfusion, the thrombi were primarily in the sensorimotor and visual cortex, disappearing within 24 h. The blood flow changes in the dMCA were more indicative of cortical ischemic conditions than diameter changes. Our method successfully establishes a photochemical TIA model based on the dMCA, allowing for the dynamic observation and control of thrombus formation and recanalization and enabling real-time monitoring of the impacts on cerebral blood flow during the acute phase of TIA.


Asunto(s)
Circulación Cerebrovascular , Modelos Animales de Enfermedad , Ataque Isquémico Transitorio , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/fisiopatología , Animales , Masculino , Trombosis/diagnóstico por imagen , Ratones , Imágenes de Contraste de Punto Láser/métodos , Arteria Cerebral Media/diagnóstico por imagen
8.
Molecules ; 29(13)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38999102

RESUMEN

Activated carbon has an excellent porous structure and is considered a promising adsorbent and electrode material. In this study, activated carbon fibers (ACFs) with abundant microporous structures, derived from natural cotton fibers, were successfully synthesized at a certain temperature in an Ar atmosphere and then activated with KOH. The obtained ACFs were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), elemental analysis, nitrogen and carbon dioxide adsorption-desorption analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption measurement. The obtained ACFs showed high porous qualities and had a surface area from 673 to 1597 m2/g and a pore volume from 0.33 to 0.79 cm3/g. The CO2 capture capacities of prepared ACFs were measured and the maximum capture capacity for CO2 up to 6.9 mmol/g or 4.6 mmol/g could be achieved at 0 °C or 25 °C and 1 standard atmospheric pressure (1 atm). Furthermore, the electrochemical capacitive properties of as-prepared ACFs in KOH aqueous electrolyte were also studied. It is important to note that the pore volume of the pores below 0.90 nm plays key roles to determine both the CO2 capture ability and the electrochemical capacitance. This study provides guidance for designing porous carbon materials with high CO2 capture capacity or excellent capacitance performance.

9.
EMBO J ; 38(18): e102075, 2019 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-31390091

RESUMEN

RIG-I-MAVS antiviral signaling represents an important pathway to stimulate interferon production and confer innate immunity to the host. Upon binding to viral RNA and Riplet-mediated polyubiquitination, RIG-I promotes prion-like aggregation and activation of MAVS. MAVS subsequently induces interferon production by activating two signaling pathways mediated by TBK1-IRF3 and IKK-NF-κB respectively. However, the mechanism underlying the activation of MAVS downstream pathways remains elusive. Here, we demonstrated that activation of TBK1-IRF3 by MAVS-Region III depends on its multimerization state and identified TRAF3IP3 as a critical regulator for the downstream signaling. In response to virus infection, TRAF3IP3 is accumulated on mitochondria and thereby facilitates the recruitment of TRAF3 to MAVS for TBK1-IRF3 activation. Traf3ip3-deficient mice demonstrated a severely compromised potential to induce interferon production and were vulnerable to RNA virus infection. Our findings uncover that TRAF3IP3 is an important regulator for RIG-I-MAVS signaling, which bridges MAVS and TRAF3 for an effective antiviral innate immune response.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Factor 3 Asociado a Receptor de TNF/metabolismo , Virosis/inmunología , Animales , Línea Celular , Modelos Animales de Enfermedad , Células HEK293 , Células HeLa , Humanos , Inmunidad Innata , Factor 3 Regulador del Interferón/metabolismo , Ratones , Mitocondrias/metabolismo , Multimerización de Proteína , Proteínas Serina-Treonina Quinasas/metabolismo , Factor 3 Asociado a Receptor de TNF/genética , Virosis/genética
10.
Retina ; 43(12): 2059-2063, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35982505

RESUMEN

PURPOSE: To report the results of a novel surgical four-point transscleral suture fixation of intraocular lens (IOL) with four hollow haptics using the double-suture technique. METHODS: We retrospectively reviewed the medical records of 15 eyes of 15 patients who underwent 4-point transscleral suture fixation of a foldable IOL using the double-suture technique. Preoperative data and follow-up data for at least 4 months were collected for all patients. RESULTS: The IOLs were fixed and centered well. The mean preoperative corrected distance visual acuity was 0.70 ± 0.54 logarithm of the minimum angle of resolution (Snellen 20/102), and it improved to 0.29 ± 0.26 logarithm of the minimum angle of resolution (Snellen 20/39) at the final follow-up ( P = 0.001). No vitreous hemorrhage, hypotony, suture breakage, retinal detachment, IOL dislocation, and iris capture was detected during the follow-up period in any of the patients. CONCLUSION: We have developed a novel technique for 4-point transscleral suture fixation of IOL using the double-suture technique with 9-0 polypropylene suture. This technique seemed to be safe and it may not require the surgeon to learn any new technique.


Asunto(s)
Implantación de Lentes Intraoculares , Lentes Intraoculares , Humanos , Implantación de Lentes Intraoculares/métodos , Polipropilenos , Estudios Retrospectivos , Esclerótica/cirugía , Técnicas de Sutura , Suturas
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