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1.
Angew Chem Int Ed Engl ; : e202411753, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136332

RESUMEN

Development of highly porous and robust HOFs for high-pressure methane and hydrogen storage remains a grand challenge due to the fragile nature of hydrogen bonds. Herein, we report a strategy of constructing double-walled framework to target highly porous and robust HOF (ZJU-HOF-5a) for extraordinary CH4 and H2 storage. ZJU-HOF-5a features a minimized twofold interpenetration with double-walled structure, in which multiple supramolecular interactions are existed between the interpenetrated walls. This structural configuration can notably enhance the framework robustness while maintaining its high porosity, affording one of the highest gravimetric and volumetric surface areas of 3102 m2 g-1 and 1976 m2 cm-3 among the reported HOFs so far. ZJU-HOF-5a exhibits an extremely high volumetric H2 uptake of 43.6 g L-1 at 77 K/100 bar and working capacity of 41.3 g L-1 under combined swing conditions, and also impressive methane storage performance with a 5-100 bar working capacity of 187 (or 159) cm3 cm-3 at 270 K (or 296 K). SCXRD studies on CH4-loaded ZJU-HOF-5a reveal that abundant supramolecular binding sites combined with ultrahigh porosities account for its high CH4 storage capacities. Combined with high stability, super-hydrophobicity, and easy-recovery, ZJU-HOF-5a is placed among the most promising materials for H2 and CH4 storage applications.

2.
Angew Chem Int Ed Engl ; 63(26): e202404734, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38635373

RESUMEN

The development of porous materials with flexible-robust characteristics shows some unique advantages to target high performance for gas separation, but remains a daunting challenge to achieve so far. Herein, we report a carboxyl-based hydrogen-bonded organic framework (ZJU-HOF-8a) with flexible-robust porosity for efficient purification of natural gas. ZJU-HOF-8a features a four-fold interpenetrated structure with dia topology, wherein abundant supramolecular entanglements are formed between the adjacent subnetworks through weak intermolecular hydrogen bonds. This structural configuration could not only stabilize the whole framework to establish the permanent porosity, but also enable the framework to show some flexibility due to its weak intermolecular interactions (so-called flexible-robust framework). The flexible-robust porosity of ZJU-HOF-8a was exclusively confirmed by gas sorption isotherms and single-crystal X-ray diffraction studies, showing that the flexible pore pockets can be opened by C3H8 and n-C4H10 molecules rather by C2H6 and CH4. This leads to notably higher C3H8 and n-C4H10 uptakes with enhanced selectivities than C2H6 over CH4 under ambient conditions, affording one of the highest n-C4H10/CH4 selectivities. The gas-loaded single-crystal structures coupled with theoretical simulations reveal that the loading of n-C4H10 can induce an obvious framework expansion along with pore pocket opening to improve n-C4H10 uptake and selectivity, while not for C2H6 adsorption. This work suggests an effective strategy of designing flexible-robust HOFs for improving gas separation properties.

3.
Adv Mater ; 36(21): e2313419, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38335452

RESUMEN

It remains an obstacle to induce the regeneration of hard dentin tissue in clinical settings. To overcome this, a P(VDF-TrFE) piezoelectric film with 2 wt% SrCl2 addition is designed. The biofilm shows a high flexibility, a harmonious biocompatibility, and a large piezoelectric d33 coefficient of 14 pC N-1, all contributing to building an electric microenvironment that favor the recruitment of dental pulp stem cells (DPSCs) and their differentiation into odontoblasts during normal chewing, speaking, etc. On the other hand, the strontium ions can be gradually released from the film, thus promoting DPSC odonto-differentiation. In vivo experiments also demonstrate that the film induces the release of dentin minerals and regeneration of dentin tissue. In the large animal dentin defect models, this piezoelectric film induces in situ dentin tissue formation effectively over a period of three months. This study illustrates a therapeutic potential of the piezoelectric film to improve dentin tissue repair in clinical settings.


Asunto(s)
Biopelículas , Pulpa Dental , Dentina , Regeneración , Células Madre , Estroncio , Dentina/química , Biopelículas/efectos de los fármacos , Pulpa Dental/citología , Estroncio/química , Estroncio/farmacología , Animales , Humanos , Regeneración/efectos de los fármacos , Células Madre/citología , Células Madre/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Odontoblastos/citología , Odontoblastos/efectos de los fármacos , Odontoblastos/metabolismo , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
4.
Toxicol Lett ; 391: 62-70, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38061439

RESUMEN

Lead (Pb), a well-known environmental pollutant, could cause damage of microglia, the resident macrophages vitally regulating inflammation in brain. Previous studies have found that Pb exposure induces typical pro-inflammatory factors release, such as tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), but what effects of Pb treatment below the dose causing these factors release are unknown. Thus, cytokines assay was performed to identify the factors released from Pb-treated BV-2 cells at 2.5 µM, causing no effects on TNF-α, IL-1ß, and IL-6 release and cell death. Cytokines assay identified low doses of Pb exposure mainly induce an increase in specific chemokines, including CXCL10, CCL2, and CXCL2, which were confirmed by ELISA. Subsequent assessment found Pb could damage mitochondria function and generate mitochondrial reactive oxygen species (mtROS), and Mito TEMPO, a specific inhibitor of mtROS, suppressed Pb-caused upregulation of CXCL10 and CCL2, but not CXCL2. Finally, we determined that mtROS mediated Pb-induced activation of NF-κB pathway, as Mito TEMPO treatment inhibited P-p65/p65 escalation during Pb treatment. Inhibition of NF-κB pathway by Bay11-7821 suppressed the release of CXCL10 and CCL2. Collectively, low dose of Pb induces the release of CXCL10 and CCL2 chemokines, but not TNF-α and IL-1ß, via mtROS/NF-κB activation in BV-2 cells.


Asunto(s)
Quimiocina CCL2 , FN-kappa B , FN-kappa B/metabolismo , Plomo/toxicidad , Factor de Necrosis Tumoral alfa/metabolismo , Citocinas/metabolismo , Quimiocinas
5.
Hortic Res ; 10(12): uhad219, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38077493

RESUMEN

Increasing photosynthesis and light capture offers possibilities for improving crop yield and provides a sustainable way to meet the increasing global demand for food. However, the poor light transmittance of transparent plastic films and shade avoidance at high planting density seriously reduce photosynthesis and alter fruit quality in vegetable crops, and therefore it is important to investigate the mechanisms of light signaling regulation of photosynthesis and metabolism in tomato (Solanum lycopersicum). Here, a combination of red, blue, and white (R1W1B0.5) light promoted the accumulation of chlorophyll, carotenoid, and anthocyanin, and enhanced photosynthesis and electron transport rates by increasing the density of active reaction centers and the expression of the genes LIGHT-HARVESTING COMPLEX B (SlLHCB) and A (SlLHCA), resulting in increased plant biomass. In addition, R1W1B0.5 light induced carotenoid accumulation and fruit ripening by decreasing the expression of LYCOPENE ß-CYCLASE (SlCYCB). Disruption of SlCYCB largely induced fruit lycopene accumulation, and reduced chlorophyll content and photosynthesis in leaves under red, blue, and white light. Molecular studies showed that ELONGATED HYPOCOTYL 5 (SlHY5) directly activated SlCYCB, SlLHCB, and SlLHCA expression to enhance chlorophyll accumulation and photosynthesis. Furthermore, R1W1B0.5 light-induced chlorophyll accumulation, photosynthesis, and SlHY5 expression were largely decreased in the slphyb1cry1 mutant. Collectively, R1W1B0.5 light noticeably promoted photosynthesis, biomass, and fruit quality through the photoreceptor (SlPHYB1 and SlCRY1)-SlHY5-SlLHCA/B/SlCYCB module in tomato. Thus, the manipulation of light environments in protected agriculture is a crucial tool to regulate the two vital agronomic traits related to crop production efficiency and fruit nutritional quality in tomato.

6.
Appl Opt ; 62(14): 3598-3605, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37706975

RESUMEN

Chaos lidar has gained significant attention due to its high spatial resolution, natural anti-interference capability, and confidentiality. However, constrained by the power of the chaos laser, the sensitivity of the linear detector, and the hardware bandwidth, chaos lidar is greatly restricted in the application of long-distance target detection and imaging. To overcome these constraints, we propose a novel, to the best of our knowledge, chaos lidar based on Geiger mode avalanched photodetectors (GM-APDs) in a previous study called chaos single-photon (CSP) lidar. In this paper, we compare the CSP lidar with the linear mode chaos lidars by combining with lidar equation. Regarding the ranging principle, the CSP lidar is fully digital and breaks through the constraints of a detector's bandwidth and ADC's sampling rate. The simulation results indicate that the detection range of the CSP lidar is approximately 35 times and 8 times greater than that of a continuous-wave chaos lidar and pulsed chaos lidar, respectively. Although the detection accuracy of the CSP lidar is only at the centimeter level and is lower than the linear mode chaos lidars, its consumption of storage resources and power is greatly reduced due to 1-bit quantization in the GM-APD. Additionally, we investigate the impact of GM-APD parameters on the signal-to-noise ratio (SNR) of the CSP lidar system and demonstrate that the dead time difference between GM-APDs has a negligible effect. In conclusion, we present and demonstrate a new chaos lidar system with a large detection range, high SNR, low storage resources and power consumption, and on-chip capability.

7.
Int J Oncol ; 63(4)2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37594129

RESUMEN

Hepatocellular carcinoma (HCC) is the most frequently diagnosed primary liver cancer with a high mortality rate and imposes a huge burden on patients and society. Recently, ubiquitin­specific protease 35 (USP35) was found to be involved in cell proliferation and mitosis, but its role in HCC remains largely unknown. The expression of USP35 in HCC and its association with patient prognosis in the study cohort and public databases was analyzed in the present study. The effects of USP35 on the malignant biological behavior of HCC were analyzed by cellular functional experiments. Mechanistically, the effect of USP35 deubiquitylation on the M2 splice isoform of pyruvate kinase (PKM2) and on the Warburg effect of tumor cells were verified by western blotting and ubiquitination assay. The results of the present study demonstrated that USP35 is highly expressed in HCC and its high expression is significantly associated with poor prognosis of patients with HCC. In the present study, it was also demonstrated that inhibiting the expression of USP35 can impair the malignant properties (proliferation, migration and invasion) of HCC tumor cells by elevating the ubiquitination level of PKM2, the deubiquitinated form of which is critical for glycolysis in tumor cells. The present study therefore indicated that USP35 may be a target in the treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Bioensayo , Western Blotting , Línea Celular , Endopeptidasas
8.
Bioengineering (Basel) ; 10(7)2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37508783

RESUMEN

This study compares the accuracy and safety of pedicle screw placement using a 3D navigation template with the free-hand fluoroscopy technique in scoliotic patients. Fifteen scoliotic patients were recruited and divided into a template group (eight cases) and a free-hand group (seven cases). All patients received posterior corrective surgeries, and the pedicle screw was placed using a 3D navigation template or a free-hand technique. After surgery, the positions of the pedicle screws were evaluated using CT. A total of 264 pedicle screws were implanted in 15 patients. Both the two techniques were found to achieve satisfactory safety of screw insertion in scoliotic patients (89.9% vs. 90.5%). In the thoracic region, the 3D navigation template was able to achieve a much higher accuracy of screw than the free-hand technique (75.3% vs. 60.4%). In the two groups, the accuracy rates on the convex side were slightly higher than on the concave side, while no significance was seen. In terms of rotational vertebrae, no significant differences were seen in Grades I or II vertebrae between the two groups. In conclusion, the 3D navigation template technique significantly increased the accuracy of thoracic pedicle screw placement, which held great potential for extensively clinical application.

9.
Sci Total Environ ; 894: 164948, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37336414

RESUMEN

Brucellosis is a highly contagious zoonotic and systemic infectious disease caused by Brucella, which seriously affects public health and socioeconomic development worldwide. Particularly, in China accumulating eco-environmental changes and agricultural intensification have increased the expansion of human brucellosis (HB) infection. As a traditional animal husbandry area adjacent to Inner Mongolia, Datong City in northwestern China is characterized by a high HB incidence, demonstrating obvious variations in the risk pattern of HB infection in recent years. In this study, we built Bayesian spatiotemporal models to detect the transfer of high-risk clusters of HB occurrence in Datong from 2005 to 2020. Geographically and Temporally Weighted Regression and GeoDetector were employed to investigate the synergistic driving effects of multiple potential risk factors. Results confirmed an evident dynamic expansion of HB from the east to the west and south in Datong. The distribution of HB showed a negative correlation with urbanization level, economic development, population density, temperature, precipitation, and wind speed, while a positive correlation with the normalized difference vegetation index, and grassland/cropland cover areas. Especially, the local animal husbandry and related industries imposed a large influence on the spatiotemporal distribution of HB. This work strengthens the understanding of how HB spatial heterogeneity is driven by environmental factors, through which helpful insights can be provided for decision-makers to formulate and implement disease control strategies and policies for preventing the further spread of HB.


Asunto(s)
Brucelosis , Humanos , Animales , Teorema de Bayes , Brucelosis/epidemiología , Brucelosis/veterinaria , Factores de Riesgo , China/epidemiología , Crianza de Animales Domésticos
10.
Opt Express ; 30(23): 41658-41670, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36366637

RESUMEN

With the advent of serial production lidars, single photon lidar faces an increasingly severe threat of crosstalk. In this paper, we first propose the concept of Chaos Single Photon (CSP) lidar and establish the theoretical model. In CSP lidar system, chaos laser replaces pulsed laser, and the physical random sequence generated by a Geiger mode avalanche photodiode (GM-APD) responding to chaos laser substitutes the traditional pseudo-random sequence. The mean density of '1' code of the CSP lidar system can exceed 10 million counts per second (Mcps) with a dead time immunity. The theoretical models of detection probability and false alarm rate are derived and demonstrated based on Poisson distribution. The bit error rate (BER) is introduced into the CSP lidar system for evaluating the range walk error intuitively. Additionally, the simulation results indicate that the CSP lidar system has a robust anti-crosstalk capability. Compared with the traditional pseudo-random single photon (PRSP) lidar system, the CSP lidar system not only overcomes range ambiguity but also has a signal to noise rate (SNR) of 60 times, reaching 10000 when the mean echo photoelectron number is 10 per nanosecond. Benefited from large-scale arrays and extremely high sensitivity properties of GM-APDs, we are looking forward to the applications of the CSP lidar in weak signal detection, remote mapping, autonomous driving, etc.

11.
RSC Adv ; 12(36): 23411-23415, 2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-36090424

RESUMEN

Hydrogen-bonded organic frameworks (HOFs) have received tremendous attention in recent years due to the good designability. However, the pure organic nature of HOFs sometimes limits the application development and performance improvement. Functionalizing is an effective strategy to control and modulate material properties, which can achieve properties that cannot be achieved by a pristine material. Herein, a series of HOF-76⊃DSMI were synthesized through functionalizing the stable AIE-based HOF-76 by incorporating a red dye which complements the deficiency of the red component of HOF-76. Then, a single matrix white light-emitting diode (WLED) was fabricated by coating the HOF-76⊃DSMI material on a 460 nm blue LED with CIE chromaticity coordinates of (0.333, 0.329), a correlated colour temperature (CCT) of 5490 K and a colour rendering index (CRI) of 80.

12.
Front Public Health ; 10: 926812, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35937257

RESUMEN

Human brucellosis (HB) has re-emerged in China since the mid-1990s, and exhibited an apparent geographic expansion shifted from the traditional livestock regions to the inland areas of China. It is often neglected in non-traditional epidemic areas, posing a serious threat to public health in big cities. We carried out a retrospective epidemiological study in Xi'an, the largest city in northwestern China. It utilizes long-term surveillance data on HB during 2008-2021 and investigation data during 2014-2021. A total of 1989 HB cases were reported in Xi'an, consisting of 505 local cases, i.e., those located in Xi'an and 1,484 non-local cases, i.e., those located in other cities. Significantly epidemiological heterogeneity was observed between them, mainly owing to differences in the gender, occupation, diagnostic delays, and reporting institutions. Serological investigations suggested that 59 people and 1,822 animals (sheep, cattle, and cows) tested positive for brucellosis from 2014 to 2021, with the annual average seroprevalence rates were 1.38 and 1.54%, respectively. The annual animal seroprevalence rate was positively correlated with the annual incidence of non-local HB cases. Multivariate boosted regression tree models revealed that gross domestic product, population density, length of township roads, number of farms, and nighttime lights substantially contributed to the spatial distribution of local HB. Approximately 7.84 million people inhabited the potential infection risk zones in Xi'an. Our study highlights the reemergence of HB in non-epidemic areas and provides a baseline for large and medium-sized cities to identify regions, where prevention and control efforts should be prioritized in the future.


Asunto(s)
Brucelosis , Animales , Brucelosis/epidemiología , Bovinos , China/epidemiología , Ciudades , Femenino , Humanos , Estudios Retrospectivos , Estudios Seroepidemiológicos , Ovinos
13.
Can J Infect Dis Med Microbiol ; 2022: 7658880, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35967090

RESUMEN

Brucellosis is a chronic infectious disease caused by brucellae or other bacteria directly invading human body. Brucellosis presents the aggregation characteristics and periodic law of infectious diseases in temporal and spatial distribution. Taking major European countries as an example, this study established the temporal and spatial distribution sequence of brucellosis, analyzed the temporal and spatial distribution characteristics of brucellosis, and quantitatively predicted its epidemic law by using different traditional or machine learning models. This paper indicates that the epidemic of brucellosis in major European countries has statistical periodic characteristics, and in the same cycle, brucellosis has the characteristics of piecewise trend. Through the comparison of the prediction results of the three models, it is found that the prediction effect of long short-term memory and convolutional long short-term memory models is better than autoregressive integrated moving average model. The first mock exam using Conv layer and data vectorizations predicted that the convolutional long short-term memory model outperformed the traditional long short-term memory model. Compared with the monthly scale, the prediction of the trend stage of brucellosis can achieve better results under the single model prediction. These findings will help understand the development trend and liquidity characteristics of brucellosis, provide corresponding scientific basis and decision support for potential risk assessment and brucellosis epidemic prevention and control, and reduce the loss of life and property.

14.
Zhongguo Zhong Yao Za Zhi ; 47(11): 2932-2937, 2022 Jun.
Artículo en Chino | MEDLINE | ID: mdl-35718514

RESUMEN

In this study, the chloroplast genome of Asarum sieboldii f. seoulense was sequenced, analyzed, and compared with chloroplast genomes of other medicinal plants in Aristolochiaceae downloaded from GenBank, aiming to clarify the characteristics of the chloroplast genome of A. sieboldii f. seoulense and the differences in chloroplast genome among medicinal plants of Aristolochiaceae. To be specific, the chloroplast genome of A. sieboldii f. seoulense was sequenced and assembled by high-throughput sequencing, and the general characteristics, repeats, inverted repeat(IR) boundary, and phylogenetic relationship of the chloroplast genomes of 11 medicinal species in Aristolochiaceae were analyzed with REPuter. The result showed that the genome of A. sieboldii f. seoulense was 167 293 bp, with large single-copy(LSC) region of 89 840 bp, small single-copy(SSC) region of 21 415 bp, IR region of 28 019 bp, and GC content of 37.9%. A total of 133 genes were annotated, including 89 protein-coding genes, 36 tRNA genes and 8 rRNA genes. The chloroplast genomes of the 11 medicinal species were 159 308-167 293 bp, with 130-134 genes annotated. Forward(F), reverse(R), complement(C), and palindromic(P) long repeats and simple sequence repeat(SSR) were found in the chloroplast genomes of five species. Among them, A. sieboldii f. seoulense had six types of SSR. In the phylogenetic tree, A. sieboldii f. seoulense and A. heterotropoides were in the same clade. The result is expected to lay a basis for the classification, identification, and phylogeny of medicinal plants in Aristolochiaceae.


Asunto(s)
Aristolochiaceae , Genoma del Cloroplasto , Plantas Medicinales , Aristolochiaceae/genética , Repeticiones de Microsatélite , Filogenia , Plantas Medicinales/genética
15.
Nat Mater ; 20(11): 1551-1558, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34294883

RESUMEN

Desalination can help to alleviate the fresh-water crisis facing the world. Thermally driven membrane distillation is a promising way to purify water from a variety of saline and polluted sources by utilizing low-grade heat. However, membrane distillation membranes suffer from limited permeance and wetting owing to the lack of precise structural control. Here, we report a strategy to fabricate membrane distillation membranes composed of vertically aligned channels with a hydrophilicity gradient by engineering defects in covalent organic framework films by the removal of imine bonds. Such functional variation in individual channels enables a selective water transport pathway and a precise liquid-vapour phase change interface. In addition to having anti-fouling and anti-wetting capability, the covalent organic framework membrane on a supporting layer shows a flux of 600 l m-2 h-1 with 85 °C feed at 16 kPa absolute pressure, which is nearly triple that of the state-of-the-art membrane distillation membrane for desalination. Our results may promote the development of gradient membranes for molecular sieving.


Asunto(s)
Estructuras Metalorgánicas , Purificación del Agua , Destilación , Membranas Artificiales , Purificación del Agua/métodos , Humectabilidad
16.
Genes Genomics ; 43(4): 379-388, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33595813

RESUMEN

BACKGROUND: In ribosome establishment and the initiation of translation, eukaryotic translation initiation factor (eIF) 3a is a pivotal functional subunit of the eIF3 complex. In various cancer types, abnormal eIF3a expression plays an important role in tumorigenesis. OBJECTIVE: We aimed to explore the role of eIF3a in human thyroid cancer (TC). MATERIAL AND METHODS: The expression of eIF3a was determined in TC tissues by qRT-PCR and immunohistochemistry (IHC) assay, respectively. In addition, the expression of eIF3a in K1 and BCPAP cells were detected by qRT-PCR. Cell proliferation, cell cycle, and cell apoptosis were assessed after eIF3a knockdown in K1 in cell line. RESULTS: The expression of eIF3a mRNA was high in TC tissues and cancer cell lines. Moreover, eIF3a expression in TC tissues indicated that high eIF3a level was associated with tumor grade. In addition, eIF3a knockdown resulted in a significantly decrease in cell proliferation and increased the apoptosis of K1 cells. Cell cycle was arrested in both the S and G2/M phase. The levels of phosphorylated ERK1/2 and surviving were decreased after eIF3a knockdown. CONCLUSION: Our study suggested that eIF3a contributed to TC cell proliferation. It may be a promising target for gene therapy in human thyroid cancer.


Asunto(s)
Factor 3 de Iniciación Eucariótica/metabolismo , Neoplasias de la Tiroides/patología , Apoptosis , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Factor 3 de Iniciación Eucariótica/genética , Factor 3 de Iniciación Eucariótica/fisiología , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias de la Tiroides/metabolismo
17.
Chem Commun (Camb) ; 56(84): 12817-12820, 2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-32966388

RESUMEN

A facile approach to the fully substituted cyclopentenones involving an unprecedented benzofuran-ring-opening is described. The cleavage of a benzofuran endocyclic C2-O bond proceeded smoothly in the absence of any transition metal catalyst or highly reactive organometallic reagent. Such benzofuran-ring-opening is delicately incorporated into an acid-catalyzed cascade process, orchestrating a novel synthetic strategy for complex cyclopentenones with excellent yields and diastereoselectivities.

18.
Technol Cancer Res Treat ; 19: 1533033820919759, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32419643

RESUMEN

Primary brain tumors are a rare occurrence in comparison to other malignancies, the most predominant form being glioma. Commonly, exposure to ionizing radiations and inheritance of associated conditions such a neurofibromatosis and tuberous sclerosis are the most common causes of development of glioma. However, understanding of the molecular mechanisms that drive glioma development is limited. We explore the role of aberration of microRNA namely miR-494-3p through long noncoding RNA WT1-AS in the development of gliomas. In this study, we found that, levels of WT1-AS were significantly reduced in glioma tissues and cell lines. The miR-494-3p levels were negatively correlated with WT1-AS levels. The cellular proliferation and invasiveness decreased in WT1-AS transfected cell lines. Further the half maximal inhibitory concentration (IC50) of chemotherapeutic agent temozolomide was significantly reduced in the presence of WT1-AS. The cotransfection of WT1-AS and miR-494-3p reduced activation of phospho-AKT (p-AKT). Expression of miR-494-3p is modulated by binding to long noncoding RNA WT1-AS. Deregulation of WT1-AS leads to aberrant expression of miR-494-3p leading to hyperactivation of AKT. This malformation may result in altering protective immune responses in malignancies. Targeting of WT1-AS, miR-494-3p, and AKT may be novel therapeutic options in treatment of glioma.


Asunto(s)
Neoplasias Encefálicas/genética , Glioma/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Apoptosis/fisiología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Glioma/metabolismo , Glioma/patología , Humanos , MicroARNs/metabolismo , Clasificación del Tumor , ARN Largo no Codificante/metabolismo , Transducción de Señal
19.
Cancer Manag Res ; 10: 3867-3873, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30288118

RESUMEN

INTRODUCTION: Currently in papillary thyroid cancer (PTC), the correlation between lymph node positivity (LN+) and patient's age at diagnosis is still inconclusive. The aim of this study was to investigate whether younger PTC patients had higher LN+ rates. PATIENTS AND METHODS: From the 1998-2013 Surveillance, Epidemiology, and End Results database, we analyzed PTC patients with at least 1 LN examined. The patients were divided into 5 groups by age separately for each T stage: ≤30; 31-40; 41-50; 51-60; >60 years. RESULTS: A total of 46,077 PTC patients were identified, including 8,386 (18.2%) patients aged ≤30 years, 10,971 (23.8%) patients aged 31-40 years, 11,646 (25.3%) patients aged 41-50 years, 8,596 (18.7%) patients aged 51-60 years, and 6,478 (14.1%) patients aged >60 years. In each T stage, LN+ rates were inversely associated with age at diagnosis, which was validated by multivariate logistic regression analysis (p<0.001). In addition, the subset of patients 30 or younger had the highest lymph node ratio compared with other subsets (p<0.001). CONCLUSION: We identified that younger PTC patients have an increased predisposition for LN+ regardless of T stage. This finding could help surgeons to select the optimal treatment for younger PTC patients.

20.
Cancer Manag Res ; 10: 465-472, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29563836

RESUMEN

OBJECTIVE: This study was to evaluate the risk factors of survival in patients with columnar cell variant (CCV) and encapsulated variant (ECV). MATERIALS AND METHODS: The Surveillance, Epidemiology, and End Results database (1988-2013) was used to compare the characteristics of CCV and ECV with those of classic papillary thyroid carcinoma (PTC). Survival was analyzed by the Kaplan-Meier method, the log-rank test, and Cox multivariate regression. Multivariate logistic regression was used to further analyze lymph node metastases and distant metastasis. There were 765 CCV, 529 ECV, and 39,035 PTC patients. ECV tumors were similar to PTC in terms of overall survival, disease-specific survival, age, sex, and distant metastasis. RESULTS: Compared with PTC, CCV tumors tended to be larger, with a higher incidence rate among males and in patients ≥65 years of age. CCV was associated with higher rates of extrathyroidal extension, multifocality, lymph node examinations, and lymph node and distant metastases (p<0.0001). Significant differences were found in 10-year overall survival (97.14% vs 89.15%, p<0.0001) and disease-specific survival (99.08% vs 93.07%, p<0.0001) between PTC and CCV. In CCV, distant metastasis (hazard ratio 5.125, p<0.0001) and lymph nodal metastasis (hazard ratio 2.152, p=0.032) predicted a poor prognosis. After adjustment, distant metastasis was independently associated with age ≥65 years, and lymph nodal metastasis was independently associated with female sex (odds ratio [OR] 0.341 [0.234-0.496]), extrathyroidal extension (OR 2.453 [1.368-4.397]), multifocality (OR 2.168 [1.318-3.569]), size >20 mm, ≤40 mm (OR 1.851 [1.170-2.928]), and size >40 mm (OR 1.847 [1.088-3.136]). CONCLUSION: ECV appears to have a similar prognosis to PTC, while CCV has a worse prognosis than classic PTC. Treatment with external beam radiotherapy and radioactive implants should be conducted carefully in patients with CCV.

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