Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 121
Filtrar
1.
Artículo en Inglés | MEDLINE | ID: mdl-38900701

RESUMEN

Objective: To investigate the application value, feasibility, and safety of modified single-port laparoscopic surgery in the treatment of pediatric inguinal hernia. Methods: One hundred and twenty cases of children with indirect inguinal hernia admitted from 2017 to 2022 were enrolled in the Control and Observation groups, with 80 and 40 cases, respectively. They underwent traditional open high ligation of the hernia sac and modified single-port laparoscopic high ligation of the hernia sac, respectively. The operation duration, surgical incision size, intraoperative bleeding, postoperative hospital stay, first ambulation time, and hospitalization expenses were compared between the two groups, as well as the incidence of surgical complications in the two groups. Results: The surgical incision size, intraoperative bleeding, postoperative hospital stay, and first ambulation time of the Observation group were less than those of the Control group. There was no significant difference in operation duration or hospitalization expenses between the two groups. Only two cases in the Observation group showed suture knot reactions after surgery, with no incision infection, inguinal hematoma, iatrogenic cryptorchidism, etc. The overall incidence of complications in the Observation group was lower than that of the Control group. Conclusion: Modified single-port laparoscopic surgery for inguinal hernia in children has the advantages of minimal invasiveness, and enhanced recovery, along with fewer complications and recurrence, hence it is worthy of recommendation in clinical practice.

2.
Front Optoelectron ; 17(1): 16, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833110

RESUMEN

In current documented studies, it has been observed that wavelength converters utilizing AlGaAsOI waveguides exhibit suboptimal on-chip wavelength conversion efficiency from the C-band to the 2 µm band, generally falling below -20.0 dB. To address this issue, we present a novel wavelength conversion device assisted by a waveguide amplifier, incorporating both AlGaAs wavelength converter and erbium-ytterbium co-doped waveguide amplifier, thereby achieving a notable conversion efficiency exceeding 0 dB. The noteworthy enhancement in efficiency can be attributed to the specific dispersion design of the AlGaAs wavelength converter, which enables an upsurge in conversion efficiency to -15.54 dB under 100 mW of pump power. Furthermore, the integration of an erbium-ytterbium co-doped waveguide amplifier facilitates a loss compensation of over 15 dB. Avoiding the use of external optical amplifiers, this device enables efficient and high-bandwidth wavelength conversion, showing promising applications in various fields, such as optical communication, sensing, imaging, and beyond.

3.
Chem Biodivers ; 21(5): e202400648, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38545941

RESUMEN

Taxodin A (1), a unique C30 terpenoid featuring an unprecedented skeleton composed of an abietane-type diterpene and a menthane-type monoterpene, was obtained from the leaves and branches of Taxodium mucronatum. The structure and absolute configuration of compound 1 was unequivocally established by the combination of extensive spectroscopic analyses and X-ray single-crystal diffraction analysis. Compound 1 exhibited potent cytotoxic activities against A549, SMMC-7721, MDA-MB-231, and SW480 cell lines with IC50 values of 15.35±0.73, 8.49±0.35, 17.53±0.79, 18.93±0.60 µM, respectively.


Asunto(s)
Antineoplásicos Fitogénicos , Ensayos de Selección de Medicamentos Antitumorales , Taxodium , Humanos , Taxodium/química , Línea Celular Tumoral , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Terpenos/química , Terpenos/farmacología , Terpenos/aislamiento & purificación , Conformación Molecular , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Hojas de la Planta/química , Relación Estructura-Actividad , Estructura Molecular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Modelos Moleculares
4.
Micromachines (Basel) ; 14(5)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37241577

RESUMEN

With the rapid development of artificial intelligence, the electronic system has fallen short of providing the needed computation speed. It is believed that silicon-based optoelectronic computation may be a solution, where Mach-Zehnder interferometer (MZI)-based matrix computation is the key due to its advantages of simple implementation and easy integration on a silicon wafer, but one of the concerns is the precision of the MZI method in the actual computation. This paper will identify the main hardware error sources of MZI-based matrix computation, summarize the available hardware error correction methods from the perspective of the entire MZI meshes and a single MZI device, and propose a new architecture that will largely improve the precision of MZI-based matrix computation without increasing the size of the MZI's mesh, which may lead to a fast and accurate optoelectronic computing system.

5.
Appl Immunohistochem Mol Morphol ; 31(5): 324-330, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36952588

RESUMEN

This study aimed to explore the correlation of Golgi phosphoprotein 3 (GOLPH3) levels in papillary thyroid carcinoma (PTC) and papillary thyroid microcarcinoma (PTMC) with clinicopathologic features. GOLPH3 expression was determined by western blotting in solid tumors and the adjacent normal thyroid tissues. Mammalian target of rapamycin (mTOR) and Ki-67 were examined by immunohistochemical staining. Significantly higher levels of GOLPH3 protein were observed in PTC and PTMC compared with the adjacent normal thyroid tissues ( P <0.001). GOLPH3 level was positively associated with lymph node metastasis and clinical stage in PTC ( P <0.05) and utterly related to the clinical stage in PTMC ( P =0.012). No correlation was observed between GOLPH3 level and other clinicopathologic parameters such as sex, local invasion, tumor number, and tumor size. The expression level of GOLPH3 protein in mTOR-positive PTC was significantly higher than in mTOR-negative PTC ( P =0.002 in PTC, P =0.022 in PTMC) and positively correlated with Ki-67 proliferation index in PTC via Pearson correlation analysis ( r =0.353, P =0.007 in PTC; r =0.583, P <0.001 in PTMC). In conclusion, the relative expression level of GOLPH3 protein was significantly higher in PTC and PTMC than in normal thyroid tissues and increased with cancer severity. It may provide adjunctive information for diagnosing and predicting prognosis in patients with PTC or PTMC.


Asunto(s)
Relevancia Clínica , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/patología , Antígeno Ki-67 , Neoplasias de la Tiroides/metabolismo , Serina-Treonina Quinasas TOR , Fosfoproteínas , Proteínas de la Membrana
6.
J Korean Neurosurg Soc ; 66(4): 400-408, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36300321

RESUMEN

OBJECTIVE: Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) is a crucial factor for the survival of neuron. The role of NMNAT2 in damage following traumatic brain injury (TBI) remains unknown. This study was designed to investigate the role of NMNAT2 in TBI-induced neuronal degeneration and neurological deficits in rats. METHODS: The TBI model was established in Sprague-Dawley rats by a weight-dropping method. Real-time polymerase chain reaction, western blot, immunofluorescence, Fluoro-Jade C staining, and neurological score analyses were carried out. RESULTS: NMNAT2 mRNA and protein levels were increased in the injured-side cortex at 6 hours and peaked 12 hours after TBI. Knocking down NMNAT2 with an injection of small interfering RNA in lateral ventricle significantly exacerbated neuronal degeneration and neurological deficits after TBI, which were accompanied by increased expression of BCL-2-associated X protein (Bax). CONCLUSION: NMNAT2 expression is increased and NMNAT2 exhibits neuroprotective activity in the early stages after TBI, and Bax signaling pathway may be involved in the process. Thus, NMNAT2 is likely to be an important target to prevent secondary damage following TBI.

7.
J Orthop Sci ; 28(6): 1373-1378, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36229352

RESUMEN

OBJECTIVE: To compare the clinical efficacy of the Femoral Neck System (FNS) vs. four cannulated screws in Pauwels III femoral neck fractures. METHODS: This retrospective study included patients with newly occurred type Pauwels III femoral neck fracture treated at author' Hospital of between January 2017 and February 2021. The patients received FNS (n = 27) or four cannulated screws (control group, n = 31). The operation time, blood loss, fracture healing time, incidence of complications (such as short femoral neck, necrosis of femoral head, nonunion of fracture, and failure of internal fixation withdrawal), and hip Harris score at the last follow-up were analyzed. RESULTS: The operation time, blood loss, and fracture healing time were not significantly different between the two groups (all P > 0.05). In the FNS group, three and one patients were with femoral neck shortening and femoral head necrosis, respectively, while no fracture nonunion or failure of internal fixation withdrawal occurred. In the control group, seven, two, one, and two patients were with femoral neck shortening, femoral head necrosis, nonunion, and internal fixation failure, respectively. The cumulative complication incidence was 14.8% and 38.7% in the FNS and control groups (P = 0.042). The excellent and good rates of the hip Harris score at the last follow-up were 92.6% and 71.0% in the FNS and control groups, respectively (P = 0.036). CONCLUSION: The study suggested that the clinical efficacy of FNS was better than internal fixation using four cannulated screws in treating Pauwels III type femoral neck fracture.


Asunto(s)
Fracturas del Cuello Femoral , Necrosis de la Cabeza Femoral , Humanos , Cuello Femoral , Estudios Retrospectivos , Tornillos Óseos , Fracturas del Cuello Femoral/diagnóstico por imagen , Fracturas del Cuello Femoral/cirugía , Resultado del Tratamiento , Fijación Interna de Fracturas
8.
Nanomaterials (Basel) ; 12(24)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36558319

RESUMEN

Nanostructure engineering has proven to be one of the most effective strategies to improve the efficiency of photoelectric devices. Herein, we numerically investigate and experimentally demonstrate a self-assembled silicon-based nanopillars and nanoholes structures, to improve the light absorption of photoelectric devices by an antireflection enhancement. The nanopillars and nanoholes structures are fabricated by the air-liquid interface self-assembly method based on polystyrene (PS) nanospheres. Additionally, the tunable antireflective properties with the different operation wavelength and nanostructures parameters have been discussed based on the Finite-Difference Time-Domain (FDTD) method. The experimental result shows that the self-assembled silicon-based nanopillars and nanoholes structures can achieve the lowest reflectivity of 1.42% (nanopillars) and 5.83% (nanoholes) in the wavelength range of 250-800 nm, which reduced 95.97% and 84.83%, respectively, compared with the plane silicon. The operation mechanism of the tunable antireflective property of self-assembled nanopillars and nanoholes structures is also analyzed in the simulation. Our study suggests that the self-assembled nanopillars and nanoholes structures are potentially attractive as improving efficiency of photoelectric devices.

9.
Zhongguo Gu Shang ; 35(11): 1081-6, 2022 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-36415196

RESUMEN

OBJECTIVE: To compare the clinical efficacy of lengthened proximal femoral nail anti-rotation(PFNA) combined with minimally invasive percutaneous plate osteosynthesis(MIPPO) and common PFNA in the treatment of AO-A3.3 intertrochanteric fracture. METHODS: The clinical data of 58 patients with AO-A3.3 intertrochanteric fracture treated from January 2015 to April 2020 were retrospectively analyzed. Among them, 27 patients were treated with extended PFNA + MIPPO plate to reconstruct the lateral wall (group A), and 31 patients were treated with closed reduction and PFNA fixation (group B). The bleeding volume, operation time, femoral neck length and tip apex distance(TAD), fracture healing time and postoperative complications were observed and compared between two groups. Harris score was used to evaluate hip joint function 10 months after operation. RESULTS: All patients were followed up for 12 to 28 months. The incision healed well after operation. The bleeding volume and operation time of group A were significantly more than that of group B (P<0.05), and the fracture healing time of group A was significantly less than that of group B(P<0.05). There was no significant difference in the length of femoral neck between two groups at 2 days after operation(P>0.05). The length of femoral neck at 6 months after operation in each group was shorter than that at 2 days after operation(P<0.05), and the shortening of femoral neck at 6 months after operation in group B was significantly shorter than that in group A(P<0.05). There was no significant difference in TAD values between two groups at the same time point(P>0.05) at 2 days and 6 months after operation. There was no significant difference in TAD values between 2 days and 6 months after operation(P>0.05). The incidence of complications in group B was significantly higher than that in group A(P<0.05). The Harris scores of hip joint function in group A were higher than those in group B 10 months after operation (P<0.05). CONCLUSION: Compared with the treatment of AO-A3 femoral intertrochanteric fracture with closed reduction and PFNA fixation, the lengthened PFNA combined with MIPPO small plate for reconstruction and fixation of the lateral wall can promote the fracture healing, improve the patient's functional recovery, and significantly reduce the complications.


Asunto(s)
Fracturas del Fémur , Fijación Intramedular de Fracturas , Fracturas de Cadera , Humanos , Clavos Ortopédicos , Estudios Retrospectivos , Fracturas de Cadera/cirugía , Placas Óseas , Fracturas del Fémur/cirugía
10.
Mikrochim Acta ; 189(11): 412, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-36216990

RESUMEN

New insights are proposed into enhancing detection of uranyl ions (UO22+) by electropolymerization brilliant cresyl blue-modified glassy carbon electrode (PBCB/GCE). The mercury-free PBCB/GCE sensor was applied to determine UO22+ in water samples by differential pulse adsorptive stripping voltammetry (DPAdSV). The unique combination of the PBCB/GCE and DPAdSV significantly improves sensitivity due to the polymer of high electroactive area and fast electron transfer rate. The DPAdSV current using a 3 mm diameter PBCB/GCE was proportional to the UO22+ concentration in the range 2.0-90.0 µg·L-1 (- 0.113 V vs. SCE) with a detection limit of 0.650 µg·L-1, RSD = 3.1% (n = 10), and 4.5% reproducibility. In addition, the sensitivity for UO22+ determination was further improved at using an 1 mm diameter PBCB/GCE, which enhances the efficiency of UO22+ deposition due to its higher current density. The 1 mm diameter PBCB/GCE based on DPAdSV technique could be used to determine uranyl ions in the concentration range 0.20-2.0 µg·L-1 (- 0.113 V vs. SCE) with a detection limit of 0.067 µg·L-1, RSD = 5.7 % (n = 10) and 5.4% reproducibility. Hence, the PBCB/GCE is a suitable candidate to substitute the mercury electrode. Graphical abstract.


Asunto(s)
Carbono , Mercurio , Iones , Oxazinas , Polímeros , Reproducibilidad de los Resultados , Agua
11.
Nanomaterials (Basel) ; 12(11)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35683731

RESUMEN

Surface anti-reflection (AR) with nanometer-scaled texture has shown excellent light trapping performance involving optical devices. In this work, we developed a simple and lithography-free structure replication process to obtain large scale surface cup-shaped nano-pillar (CSNP) arrays for the first time. A method of depositing was used for pattern transfer based on PMMA pre-coated through-hole anodic aluminum oxide (AAO) thin film (~500 nm), and eventually, the uniformity of the transferred nanostructures was guaranteed. From the spectrum (250 nm~2000 nm) dependent measurements, the CSNP nanostructured Si showed excellent AR performance when compared with that of the single-polished Si. Moreover, the CSNP was found to be polarization insensitive and less dependent on incidence angles (≤80°) over the whole spectrum. To further prove the excellent antireflective properties of the CSNP structure, thin film solar cell models were built and studied. The maximum value of Jph for CSNP solar cells shows obvious improvement comparing with that of the cylinder, cone and parabola structured ones. Specifically, in comparison with the optimized Si3N4 thin film solar cell, an increment of 54.64% has been achieved for the CSNP thin film solar cell.

12.
Nanomaterials (Basel) ; 12(12)2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35745316

RESUMEN

Reliability of nonvolatile resistive switching devices is the key point for practical applications of next-generation nonvolatile memories. Nowadays, nanostructured organic/inorganic heterojunction composites have gained wide attention due to their application potential in terms of large scalability and low-cost fabrication technique. In this study, the interaction between polyvinyl alcohol (PVA) and two-dimensional material molybdenum disulfide (MoS2) with different mixing ratios was investigated. The result confirms that the optimal ratio of PVA:MoS2 is 4:1, which presents an excellent resistive switching behavior. Moreover, we propose a resistive switching model of Ag/ZnO/PVA:MoS2/ITO bilayer structure, which inserts the ZnO as the protective layer between the electrode and the composite film. Compared with the device without ZnO layer structure, the resistive switching performance of Ag/ZnO/PVA:MoS2/ITO was improved greatly. Furthermore, a large resistive memory window up to 104 was observed in the Ag/ZnO/PVA:MoS2/ITO device, which enhanced at least three orders of magnitude more than the Ag/PVA:MoS2/ITO device. The proposed nanostructured Ag/ZnO/PVA:MoS2/ITO device has shown great application potential for the nonvolatile multilevel data storage memory.

13.
Phys Chem Chem Phys ; 24(26): 16021-16030, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35730747

RESUMEN

In the present work, we used molecular dynamics simulations to study the effects of carbon nanotube (CNT) contents on stretch-induced crystallization behavior in CNT filled polyethylene systems. During high-temperature stretching, the stretching is responsible for the orientation of CNTs, which then facilitates segment orientation and conformational transition from the gauche-conformation into the trans-conformation in interfacial regions. The systems with higher CNT contents have a higher degree of orientation and higher contents of trans-conformation during stretching, resulting in the formation of more precursors. During subsequent crystallization, the initial crystallization rate increases with the increase of the CNT content due to the increase in precursor contents in interfacial regions. However, after the CNT content exceeds a certain value, a filler network would be formed by CNTs, which can restrict chain movements and then lead to a decrease in the overall crystallization rate in the systems with high CNT contents.

14.
Chem Biodivers ; 19(2): e202100861, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34860463

RESUMEN

Vibsane-type diterpenoids isolated from the genus Viburnum, are rare 6-11 membered ring polysubstituted macrocyclic diterpenoids. Since the first report of vibsane-type diterpenoids from V. odoratissimum in 1980, they have attracted the attention of scientists due to their complex structures, excellent biological activities, and great synthetic challenges. Recently, there are some notable research achievements on the discovery, synthesis, structural modification, and pharmacological mechanism of vibsane-type diterpenoids. Therefore, we will focus on these aspects to review important achievements of vibsane diterpenoids between 1980-2021.


Asunto(s)
Diterpenos , Viburnum , Diterpenos/química , Diterpenos/farmacología , Estructura Molecular , Viburnum/química
16.
Molecules ; 26(21)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34770935

RESUMEN

Catharanthus roseus is a well-known traditional herbal medicine for the treatment of cancer, hypertension, scald, and sore in China. Phytochemical investigation on the twigs and leaves of this species led to the isolation of two new monoterpene indole alkaloids, catharanosines A (1) and B (2), and six known analogues (3-8). Structures of 1 and 2 were established by 1H-, 13C- and 2D-NMR, and HREIMS data. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 2 represented an unprecedented aspidosperma-type alkaloid with a 2-piperidinyl moiety at C-10. Compounds 6-8 exhibited remarkable Cav3.1 low voltage-gated calcium channel (LVGCC) inhibitory activity with IC50 values of 11.83 ± 1.02, 14.3 ± 1.20, and 14.54 ± 0.99 µM, respectively.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo T/química , Catharanthus/química , Alcaloides Indólicos/farmacología , Monoterpenos/farmacología , Extractos Vegetales/farmacología , Bloqueadores de los Canales de Calcio/química , Canales de Calcio Tipo T/metabolismo , Relación Dosis-Respuesta a Droga , Alcaloides Indólicos/química , Conformación Molecular , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Monoterpenos/química , Extractos Vegetales/química , Relación Estructura-Actividad
17.
Phys Chem Chem Phys ; 23(32): 17382-17391, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34350912

RESUMEN

Polymer crystallization under chain and space confinements is studied by Monte Carlo simulation. The simulation results show that the crystallinity and melting temperature of confined systems increase with the increase of free chain content. Furthermore, the crystallinity and melting temperature of confined systems with larger lateral size are higher than those with smaller lateral size. These findings are in good agreement with the conclusions obtained in some experiments. An important phenomenon that cannot be observed in experiments has been confirmed, that is, the tethering point can be used as the nucleation site. For the confined polymer system with the lateral size of 8 lattice points, with the increase of free chain content, the surface free energy of the nuclei and the diffusion activation energy of the chains decrease due to the combined effects of chain conformation size and chain movement ability, which leads to the enhancement of the nucleation ability of polymers. However, for the confined polymer system with lateral size of 12 lattice points, with the increase of free chain content, the nucleation sites decrease and the critical free energy barrier increases, which are not conducive to nucleation. Moreover, the existence of interfacial interactions can also significantly change the crystallization of confined polymers. Our results indicate the crystallization kinetics of the confined polymer from a microscopic point of view.

18.
Med Sci Monit ; 27: e931969, 2021 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-34455415

RESUMEN

BACKGROUND Midfoot deformity and injury can affect the internal pressure distribution of the foot. This study aimed to use 3D finite element and biomechanical analyses of midfoot von Mises stress levels in flatfoot, clubfoot, and Lisfranc joint injury. MATERIAL AND METHODS Normal feet, flatfeet, clubfeet (30 individuals each), and Lisfranc injuries (50 individuals) were reconstructed by CT, and 3D finite element models were established by ABAQUS. Spring element was used to simulate the plantar fascia and ligaments and set hyperelastic coefficients in encapsulated bone and ligaments. The stance phase was simulated by applying 350 N on the top of the talus. The von Mises stress of the feet and ankle was visualized and analyzed. RESULTS The von Mises stress on healthy feet was higher in the lateral metatarsal and ankle bones than in the medial metatarsal bone. Among the flatfoot group, the stress on the metatarsals, talus, and navicular bones was significantly increased compared with that on healthy feet. Among patients with clubfeet, stress was mainly concentrated on the talus, and stress on the lateral metatarsal and navicular bones was significantly lower. The von Mises stress on the fractured bone was decreased, and the stress on the bone adjacent to the fractured bone was higher in Lisfranc injury. During bone dislocation alone or fracture accompanied by dislocation, the von Mises stress of the dislocated bone tended to be constant or increased. CONCLUSIONS Prediction of von Mises stress distribution may be used clinically to evaluate the effects of deformity and injury on changes in structure and internal pressure distribution on the midfoot.


Asunto(s)
Pie Equinovaro/fisiopatología , Análisis de Elementos Finitos/estadística & datos numéricos , Pie Plano/fisiopatología , Traumatismos de los Pies/fisiopatología , Articulaciones del Pie/fisiopatología , Artropatías/fisiopatología , Estrés Mecánico , Adulto , Fenómenos Biomecánicos , Femenino , Estudios de Seguimiento , Articulaciones del Pie/lesiones , Humanos , Masculino , Pronóstico
19.
Chemistry ; 27(48): 12305-12309, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34231284

RESUMEN

Chirality at different levels is widely observed in nature, but the clue to connect it all together, and the way chirality transfers among different levels are still obscure. Herein, a l-/d-lysine-based self-assembly system was constructed, in which two-step chirality transfer among three different levels was observed in aqueous solution. The chirality originated from the point chirality of amino acid derivatives l-/d-PyLys hydrochloride, and was transferred to the planar conformational chirality of water-soluble pillar[5]arene pR-/pS-WP5. Then, with the aid of pR-/pS-WP5, nanoparticles were formed that exhibited L-/R-handed circularly polarized luminescence with a dissymmetry factor of up to ±0.001, arising from pyrene chiral excimers. This multilevel chirality transfer not only provides a perspective to trace potential clues, and to pursue certain ways by which the chirality transfers, but also offers a strategy to create controllable CPL emission in aqueous media.


Asunto(s)
Luminiscencia , Nanopartículas , Aminoácidos , Estereoisomerismo , Agua
20.
Nat Prod Bioprospect ; 11(5): 557-564, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34089490

RESUMEN

Three new clerodane-type diterpene glycosides, (5R,6S,8R,9S,10R)-6-O-[ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl]cleroda-3,13(16),14-diene (1), (5R,6S,8R,9S,10R,13S)-6-O-[ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl]-2-ox-oneocleroda-3,13-dien-15-ol (2), (5R,6S,8R,9S,10R)-6-O-[ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl]-(13E)-2-oxoneocleroda-3,14-dien-13-ol (3), together with two known compounds 4 and 5 were isolated from Dicranopteris pedata. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configuration of compound 2 was determined by ECD calculations. In addition, compound 1 exhibited weak inhibitory activities against SMMC-7721, MCF-7 and SW480.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...