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1.
Bioorg Med Chem Lett ; 107: 129794, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38735344

RESUMEN

Chem-KVL is a tandem repeating peptide, with 14 amino acids that was modified based on a short peptide from a fragment of the human host defense protein chemerin. Chem-KVL increases cationicity and hydrophobicity and shows broad-spectrum antibacterial activity. To determine the molecular determinants of Chem-KVL and whether staple-modified Chem-KVL would improve antibacterial activity and protease stability or decrease cytotoxicity, we combined alanine and stapling scanning, and designed a series of alanine and staple-derived Chem-KVL peptides, termed Chem-A1 to Chem-A14 and SCL-1 to SCL-7. We next examined their antibacterial activity against several gram-positive and gram-negative bacteria, their proteolytic stability, and their cytotoxicity. Ala scanning of Chem-KVL suggested that both the positively charged residues (Lys and Arg) and the hydrophobic residues (Lue and Val) were critical for the antibacterial activities of Chem-KVL peptide. Of note, Chem-A4 was able to remarkably inhibit the growth of gram-positive and gram-negative bacteria when compared to the original peptide. And the antibacterial activities of stapled SCL-4 and SCL-7 were several times higher than those of the linear peptide against gram-positive and gram-negative bacteria. Stapling modification of peptides resulted in increased helicity and protein stability when compared with the linear peptide. These stapled peptides, especially SCL-4 and SCL-7, may serve as the leading compounds for further optimization and antimicrobial therapy.


Asunto(s)
Alanina , Antibacterianos , Bacterias Gramnegativas , Bacterias Grampositivas , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Bacterias Grampositivas/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Alanina/química , Alanina/farmacología , Humanos , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Péptidos Antimicrobianos/síntesis química , Relación Estructura-Actividad , Mutación , Secuencia de Aminoácidos
2.
Int J Nanomedicine ; 19: 4199-4215, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38766657

RESUMEN

Background: Breast cancer is the most common cancer in women and one of the leading causes of cancer death worldwide. Ferroptosis, a promising mechanism of killing cancer cells, has become a research hotspot in cancer therapy. Simvastatin (SIM), as a potential new anti-breast cancer drug, has been shown to cause ferroptosis of cancer cells and inhibit breast cancer metastasis and recurrence. The purpose of this study is to develop a novel strategy boosting ferroptotic cascade for synergistic cancer therapy. Methods: In this paper, iron base form of layered double hydroxide supported simvastatin (LDHs-SIM) was synthesized by hydrothermal co-precipitation method. The characterization of LDHs-SIM were assessed by various analytical techniques, including ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). Biological activity, ferroptosis mechanism and biocompatibility were analyzed through in vivo and in vitro analysis, so as to evaluate its therapeutic effect on breast cancer. Results: The constructed LDHs-SIM nanosystem can not only release SIM through mevalonate (MVA) pathway, inhibit the expression of glutathione peroxidase 4 (GPX4), inhibit the expression of SLC7A11 and reduce the synthesis efficiency of GSH, but also promote the accumulation of Fe2+ in cells through the release of Fe3+, and increase the intracellular ROS content. In addition, LDHs-SIM nanosystem can induce apoptosis of breast cancer cells to a certain extent, and achieve the synergistic effect of apoptosis and ferroptosis. Conclusion: In the present study, we demonstrated that nanoparticles of layered double hydroxides (LDHs) loaded with simvastatin were more effective than a free drug at inhibiting breast cancer cell growth, In addition, superior anticancer therapeutic effects were achieved with little systemic toxicity, indicating that LDHs-SIM could serve as a safe and high-performance platform for ferroptosis-apoptosis combined anticancer therapy.


Asunto(s)
Apoptosis , Neoplasias de la Mama , Ferroptosis , Hidróxidos , Simvastatina , Ferroptosis/efectos de los fármacos , Femenino , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Hidróxidos/química , Hidróxidos/farmacología , Simvastatina/farmacología , Simvastatina/química , Simvastatina/administración & dosificación , Apoptosis/efectos de los fármacos , Animales , Línea Celular Tumoral , Nanopartículas/química , Sinergismo Farmacológico , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Ratones Desnudos , Ratones Endogámicos BALB C , Células MCF-7 , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo
3.
Artículo en Inglés | MEDLINE | ID: mdl-38607616

RESUMEN

The unique metal-insulator transition of VO2 is very suitable for dynamic electromagnetic (EM) regulation materials due to its sharp change in electrical conductivity. Here, we have developed an off/on switchable electromagnetic interference (EMI) shielding composite by interconnecting VO2 nanowires (NWs) in poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) to form conductive networks, resulting in outstanding performance at the X and Ku bands with maximum change values of 44.8 and 59.4 dB, respectively. The unique insulator-to-metal transition (IMT) of VO2 NWs has dominated the variation of polarization loss (εp″) and conductivity loss (εσ″) for the composites, which is the mechanism of EMI shielding switching between off and on states. Furthermore, the composite exhibits good cycling stability of the off/on switchable EMI shielding performance and has excellent mechanical properties, especially with 200 times abrasion resistance without obvious weight loss. This study provides a unique approach for dynamic switching of EM response with the potential to construct practical intelligent EM response systems for next-generation smart electromagnetic devices in various scenarios.

4.
Mol Carcinog ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651944

RESUMEN

Na, K-ATPase interaction (NKAIN) is a transmembrane protein family, which can interact with Na, K-ATPase ß1 subunit. NKAIN1 plays an important role in alcohol-dependent diseases such as endometrial and prostate cancers. However, the relationship between NKAIN1 and human breast cancer has not been studied. Hence, this study aimed to explore the relationship between NKAIN1 expression and breast cancer. Data used in this study were mainly from the Cancer Genome Atlas, including differential expression analysis, Kaplan-Meier survival analysis, receiver operating characteristic curve analysis, multiple Cox regression analysis, co-expression gene analysis, and gene set enrichment analysis. Analyses were performed using reverse transcription-quantitative polymerase chain reaction, western blot analysis, and immunohistochemistry on 46 collected samples. The knockdown or overexpression of NKAIN1 in vitro in MCF-7 and MDA-MB-231 cell lines altered the proliferation and migration abilities of tumor cells. In vivo experiments further confirmed that NKAIN1 knockdown effectively inhibited the proliferation and migration of cancer cells. Therefore, our study identified NKAIN1 as an oncogene that is highly expressed in breast cancer tissues. The findings highlight the potential of NKAIN1 as a molecular biomarker of breast cancer.

5.
ACS Appl Mater Interfaces ; 16(8): 10352-10360, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38357765

RESUMEN

Reconfigurable infrared (IR) materials have widespread applications in thermal management and smart IR concealment. Although various reconfigurable IR materials can be customized by positive or negative differential VO2-based resonators, their insightful mechanism remains unknown. Here, we comprehensively investigate the fundamental design rule of reconfigurable thermal radiation between positive and negative differential thermal radiation properties for the first time. Importantly, the skin depth of VO2 film in the metal state is investigated to clarify the transformation from positive to negative differential thermal radiation properties, and the critical thickness is further derived, providing important guidance in designing the reconfigurable thermal radiation regulator. Furthermore, the reconfigurable multistate thermal images had been presented into one plate. The resulting emittance variation (△ε8-14 µm) of the VO2-based resonator can change from 0.61 to -0.53, which consummates the ability for diverse demands such as infrared concealment, thermal illusion, and thermal management. This work constitutes a promising and universal route toward designing whole smart devices and may create new scientific and technological opportunities for platforms that can benefit from reconfigurable electromagnetic manipulation.

6.
Math Biosci Eng ; 20(11): 19152-19173, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-38052594

RESUMEN

In order to obtain an optimal trajectory for indoor AGV, this paper combined an improved ACO and fuzzy DWA (IACO-DWA) algorithm, which can provide an optimal path with collision-free under higher optimization efficiency. The highlights of this paper are detailed as follows: Firstly, an improved adaptive pseudo-random transition strategy is adopted in the state transition probability with an angle factor. A reward and punishment mechanism is introduced in the pheromone updating strategy, then a path optimization strategy called IACO is proposed for the more optimized path. Secondly, IDWA adopted three fuzzy controllers of direction, security and adjustment coefficients through evaluating directional and safety principles, then improving the angular velocity by processing the linear velocity with linear normalization. By adapting to the changes of the environment, the IDWA parameters can be dynamically adjusted to ensure the optimal running speed and reasonable path of AGV. Thirdly, aiming to deal with the path-planning problem in complex environments, we combined IACO with IDWA, the hybrid algorithm involves dividing the globally optimal path obtained from IACO planning into multiple virtual sub-target points. IDWA completes the path planning by switching between these local target points, thereby improving the efficiency of the path planning. Finally, simulations is verified by Matlab and experiment results on the QBot2e platform are given to verify IACO-DWA algorithm's effectiveness and high performance.

7.
Eur J Med Res ; 28(1): 510, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964281

RESUMEN

BACKGROUND: Breast cancer is the most common malignant tumor among women worldwide. GREB1L is a protein-coding gene. Previous studies have shown that GREB1L plays a vital role in lung and gastric adenocarcinoma. Currently, there is no relevant report about its role in breast cancer. METHODS: The Cancer Genome Atlas database was used to compare the expression level of GREB1L between tumor and normal tissues. The TISIDB website was used for prognosis analysis. The LinkedOmics database was used to predict the potential biological mechanism of GREB1L in breast cancer. Immunohistochemistry was used to detect the GREB1L expression level in breast tissue. Western blotting was used to detect the GREB1L expression level in cell lines. Transwell assays, CCK-8 cell proliferation assays, and colony formation assays were used to detect the migration, invasion, proliferation, and colony formation abilities of cells. Subcutaneous xenograft models were used to detect the in vivo tumor formation abilities of cells. RESULTS: GREB1L is highly expressed in breast cancer tissues and breast cancer cells. KEGG enrichment analysis suggested that GREB1L participates in the regulation of the Hedgehog signaling pathway; changes in GREB1L expression affected the migration and invasion abilities of MCF7 and MDA-MB-231 cells. Although changes in GREB1L expression did not affect their proliferation and colony formation abilities in vitro and in vivo, they affected the expression of tumor metastasis-related genes in vivo. The overexpression of GREB1L in breast cancer predicted a favorable prognosis. CONCLUSION: These results showed that GREB1L is involved in the development of breast cancer, and it may be a potential molecular marker for predicting the prognosis of breast cancer.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Pronóstico , Transducción de Señal
8.
Front Biosci (Landmark Ed) ; 28(8): 181, 2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37664932

RESUMEN

BACKGROUND: A long-term consumption of saturated fat significantly increases the concentration of saturated fatty acids in serum, which accelerates the appearance of senescence markers in ß-cells and leads to their dysfunction. An understanding of the mechanisms underlying ß-cell senescence induced by stearic acid and the exploration of effective agents preventing it remains largely unclear. Here, we aimed to investigate the protective effect of metformin against stearic acid-treated ß-cell senescence and to assess the involvement of miR-297b-5p in this process. METHODS: To identify senescence, we measured senescence-associated ß-galactosidase activity and the expression of senescence-related genes. Gain and loss of function approaches were applied to explore the role of miR-297b-5p in stearic acid-induced ß-cell senescence. Bioinformatics analysis and a luciferase activity assay were used to predict the downstream targets of miR-297b-5p. RESULTS: Stearic acid markedly induced senescence and suppressed miR-297b-5p expression in mouse ß-TC6 cells, which were significantly alleviated by metformin. After transfection of miR-297b-5p mimics, stearic acid-evoked ß-cell senescence was remarkably prevented. Insulin-like growth factor-1 receptor was identified as a direct target of miR-297b-5p. Inhibition of the insulin-like growth factor-1 receptor prevented stearic acid-induced ß-cell senescence and dysfunction. Moreover, metformin alleviates the impairment of the miR-297b-5p inhibitor in ß-TC6 cells. Additionally, long-term consumption of a high-stearic-acid diet significantly increased senescence and reduced miR-297b-5p expression in mouse islets. CONCLUSIONS: These findings imply that metformin alleviates ß-cell senescence by stearic acid through upregulating miR-297b-5p to suppress insulin-like growth factor-1 receptor expression, thereby providing a potential target to not only prevent high fat-diet-induced ß-cell dysfunction but also for metformin therapy in type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Metformina , MicroARNs , Receptor IGF Tipo 1 , Animales , Ratones , Factor I del Crecimiento Similar a la Insulina , Metformina/farmacología , MicroARNs/genética , Ácidos Esteáricos/farmacología , Receptor IGF Tipo 1/genética
9.
ACS Omega ; 8(21): 18435-18448, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37273596

RESUMEN

MicroRNAs (miRNAs) play an essential role in cancer therapy, but the disadvantages of its poor inherent stability, rapid clearance, and low delivery efficiency affect the therapeutic efficiency. Loading miRNAs by nanoformulations can improve their bioavailability and enhance therapeutic efficiency, which is an effective miRNA delivery strategy. In this study, we synthesized layered double hydroxides (LDH), which are widely used as carriers of drugs or genes due to the characteristics of good biocompatibility, high loading capacity, and pH sensitivity. We loaded the suppressor oncogene miR-30a on LDH nanomaterials (LDH@miR-30a) and determined the mass ratio of miRNA binding to LDH by agarose gel electrophoresis. LDH@miR-30a was able to escape the lysosomal pathway and was successfully phagocytosed by breast cancer SKBR3 cells and remained detectable in the cells after 24 h of co-incubation. In vitro experiments showed that LDH@miR-30a-treated SKBR3 cells showed decreased proliferation and cell cycle arrest in the G0/G1 phase and LDH@miR-30a was able to regulate the epithelial-mesenchymal transition (EMT) process and inhibit cell migration and invasion by targeting SNAI1. Meanwhile, in vivo experiments showed that nude mice treated with LDH@miR-30a showed a significant reduction in their solid tumors and no significant impairment of vital organs was observed. In conclusion, LDH@miR-30a is an effective drug delivery system for the treatment of breast cancer.

10.
Biomed Pharmacother ; 165: 115009, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37343435

RESUMEN

Tumor cells are able to use glycolysis to produce energy under hypoxic conditions, and even under aerobic conditions, they rely mainly on glycolysis for energy production, the Warburg effect. Conventional tumor therapeutic drugs are unidirectional, lacking in targeting and have limited therapeutic effect. The development of a large number of nanocarriers and targeted glycolysis for the treatment of tumors has been extensively investigated in order to improve the therapeutic efficacy. This paper reviews the research progress of nanocarriers based on targeting key glycolytic enzymes and related transporters, and combines nanocarrier systems with other therapeutic approaches to provide a new strategy for targeted glycolytic treatment of tumors, providing a theoretical reference for achieving efficient targeted treatment of tumors.


Asunto(s)
Antineoplásicos , Sistema de Administración de Fármacos con Nanopartículas , Neoplasias , Efecto Warburg en Oncología , Sistema de Administración de Fármacos con Nanopartículas/administración & dosificación , Sistema de Administración de Fármacos con Nanopartículas/farmacología , Neoplasias/tratamiento farmacológico , Efecto Warburg en Oncología/efectos de los fármacos , Proteínas Facilitadoras del Transporte de la Glucosa/antagonistas & inhibidores , Hexoquinasa/antagonistas & inhibidores , Fosfofructoquinasas/antagonistas & inhibidores , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Humanos
11.
J Int Med Res ; 51(1): 3000605221149880, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36688452

RESUMEN

OBJECTIVE: To identify risk factors related to structural incomplete response (SIR) in papillary thyroid carcinoma (PTC) and develop a nomogram for PTC patients. METHODS: In this respective study, clinical, ultrasonic, and pathological data of PTC patients treated at our institute between 2016 and 2020 were analyzed. Patients were randomly split into training and validation sets at a ratio of 7:3. Multivariate Cox regression analysis was conducted to determine independent prognostic factors. On the basis of these factors, a nomogram was built to predict SIR. P value, concordance index, calibration plots and decision curve analysis were used to evaluate the model. RESULTS: Multivariate Cox regression analysis showed that BRAF V600E status, lymph node metastasis, sex, tumor size, margin, and surgical procedure were independent prognostic factors. In the validation set, the concordance index of the nomogram was 0.774 (95% confidence interval: 0.703-0.845). Calibration plots at 3 and 5 years showed no apparent difference between predicted SIR probability and the actual SIR proportion. Additionally, the nomogram had good net clinical benefit according to the decision curve analysis compared with cases that were treat-all or treat-none. CONCLUSION: We build a nomogram to predict individualized outcomes and help postoperative surveillance in PTC patients.


Asunto(s)
Nomogramas , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo , Estudios Retrospectivos , Factores de Riesgo , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología
12.
Int J Endocrinol ; 2022: 5181386, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36467461

RESUMEN

DPP4 (dipeptidyl peptidase 4) is expressed in many cancers, but the relationship between DPP4 and thyroid carcinoma (THCA) is incompletely understood. We aim to explore the expression of DPP4 in THCA and the correlation between DPP4 expression with the prognosis of THCA and antitumor immunity. We systematically analyzed data from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Gene Expression Omnibus (GEO) databases and explored DPP4 expression, its impact on prognosis, and its relationship with antitumor immunity in THCA. Next, we collected 18 pairs of fresh THCA and adjacent paracancerous tissues and performed RT-qPCR to validate the DPP4 mRNA level. Concurrently, immunohistochemistry (IHC) analysis was performed on 12 pairs of paraffin-embedded tissues of medullary thyroid carcinoma (MTC) and paracancerous tissues to validate the DPP4 protein level. Bioinformatics analysis showed that DPP4 mRNA expression in THCA was significantly higher than that in paracancerous tissues (p < 0.01). DPP4 was expressed at the highest levels in MTC than in other pathological types. The DPP4 expression level was different between groups with different clinical characteristics. The higher the DPP4 expressed in THCA, the lower the disease-free survival (DFS) was (HR = 1.8, p=0.048). DPP4 was significantly correlated with immune cell infiltration and immune response and was positively associated with 21 immune checkpoint genes (ICGs) in THCA (p < 0.05). The results of RT-qPCR showed that the relative mRNA expression of DPP4 was significantly upregulated in 18 THCA tissues compared to that in paracancerous tissues (p=0.011). IHC results showed that the DPP4 protein level was higher in 12 MTC tissues than in paracancerous tissues (p=0.011). In conclusion, DPP4 is a potential prognostic marker of THCA and may become an effective target for immunotherapy.

13.
Theranostics ; 12(15): 6665-6681, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36185610

RESUMEN

Rationale: Although stapled peptides offer a powerful solution to overcome the susceptibility of linear peptides to proteolytic degradation and improve their ability to cross membranes, an efficient and durable disease treatment strategy has not yet been developed due to the inevitable elimination of peptide inhibitors and rapid accumulation of target proteins. Methods: Herein we developed stapled peptide-based proteolysis-targeting chimeras (SP-PROTACs), that simultaneously exhibited improved cellular uptake and proteolytic stability attributed to the stapled peptides, and efficient target protein degradation promoted by the PROTACs. Based on the PMI peptide with dual specificity for both MDM2 and MDMX, a series of SP-PROTACs were designed. Results: Among them, the optimized SPMI-HIF2-1 exhibited similar binding affinity with MDM2 and MDMX but obviously higher helical contents, improved proteolytic stability, better cellular permeability, and a better pharmacokinetic profile compared with its linear counterpart. Importantly, SPMI-HIF2-1 could effectively kill cancer cells and inhibit tumor progression in subcutaneous and orthotopic colorectal cancer xenograft models through simultaneously promoting the atypical degradation of both MDM2 and MDMX and durable p53 activation. An FP-based binding assay and structural modeling analysis of the ternary complex suggested that SPMI-HIF2-1 simultaneously bound with the target protein and E3 ligase. Conclusion: Our findings not only provide a new class of anticancer drug candidates, but also bridge the gap and reduce the physical distance between peptides and PROTACs.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proteínas de Ciclo Celular/metabolismo , Neoplasias/tratamiento farmacológico , Péptidos/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
14.
J Ultrasound Med ; 41(12): 3023-3029, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35670148

RESUMEN

OBJECTIVES: To develop a novel ultrasound (US) plane to diagnose palatine tonsillar hypertrophy objectively in children. METHODS: Tonsillar ultrasonography of children (age 2-14 years) who had a clinical diagnosis of tonsillar hypertrophy or not were analyzed retrospectively. Clinical data (including gender, age, body mass index (BMI)), and volume (V) of tonsils measured by the US, were recorded. Furthermore, we found a new US plane to diagnose tonsillar hypertrophy and named it the submental oblique cross-section. In this plane, diameters of the left tonsil, right tonsil, and central oropharynx were designated as T1, T2, and O. Then, we calculated the ratio by the formula (T1 + T2)/O. RESULTS: A total of 172 cases (85 hypertrophy and 87 non-hypertrophy) were included in this study. There were no significant differences in gender (P = .844), age (P = .666), and BMI (P = .089) between the groups. In the non-hypertrophy group, the V of both sides had a positive linear correlation with age or BMI. In contrast, there was no linear correlation between ratio and age or BMI. The area under the curve (AUC) of ratio and V was 0.970 (95%CI: 0.947-0.993) and 0.835 (95%CI: 0.778-0.893) by receiver operating characteristic (ROC) analysis, respectively. The optimal cutoff value of ratio for diagnosis of tonsillar hypertrophy was 2.293 (sensitivity = 88.2%, specificity = 95.4%). CONCLUSIONS: We established a new US section to evaluate tonsillar hypertrophy. This approach could be easily acquired and provide a reference value to guide clinical practice.


Asunto(s)
Tonsila Palatina , Niño , Humanos , Preescolar , Adolescente , Tonsila Palatina/diagnóstico por imagen , Proyectos Piloto , Estudios Retrospectivos , Hipertrofia/diagnóstico por imagen , Ultrasonografía
15.
ACS Appl Mater Interfaces ; 14(2): 2683-2690, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34981915

RESUMEN

Dynamic thermal management materials attract fast-increasing interest due to their adaptability to changing environments and greater energy savings as compared to static materials. However, the high transition temperature and the low emittance tunability of the vanadium dioxide (VO2)-based infrared radiation regulators limit their practical applications. This study addresses these issues by proposing a smart infrared radiation regulator based on a Fabry-Pérot cavity structure (VO2/HfO2/Al), which is prepared by high-power impulse magnetron sputtering (HiPIMS) and has the potential for large-scale production. Remarkably, the outstanding emittance tunability reaches 0.51, and the phase transition temperature is lowered to near a room temperature of 27.5 °C by tungsten (W) doping. In addition, a numerical thermal management power of 196.3 W/m2 (at 8-14 µm band) can be obtained from 0 to 60 °C. As a proof-of-concept, the demonstrated capabilities of the VO2 infrared radiation regulator show great potentials in a wide range of applications for the thermal management of buildings and vehicles.

16.
J Med Chem ; 64(23): 17486-17495, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34818014

RESUMEN

The pandemic of acute respiratory disease in 2019 caused by highly pathogenic and infectious SARS-CoV-2 has seriously endangered human public safety. The 6-HB (HR1-HR2 complex) formation occurring in the process of spike protein-mediated membrane fusion could serve as a conserved and potential target for the design of fusion inhibitors. Based on the HR2 domain of 6-HB, we designed and synthesized 32 stapled peptides using an all-hydrocarbon peptide stapling strategy. Owing to the improved proteolytic stability and higher helical contents, the optimized stapled peptides termed SCH2-1-20 and SCH2-1-27 showed better inhibitory activities against pseudo and authentic SARS-CoV-2 compared to the linear counterpart. Of note, SCH2-1-20 and SCH2-1-27 were proved to interfere with S protein-mediated membrane fusion. Structural modeling indicated similar binding modes between SCH2-1-20 and the linear peptide. These optimized stapled peptides could serve as potent fusion inhibitors in treating and preventing SARS-CoV-2, and the corresponding SAR could facilitate further optimization.


Asunto(s)
Glicoproteína de la Espiga del Coronavirus , Fusión de Membrana , Pandemias , Unión Proteica
17.
Chem Commun (Camb) ; 57(17): 2148-2151, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33522525

RESUMEN

A layered coordination polymer (CP) with the fine-tuned alignment of four diolefinic ligands has been designed by shifting the coordination site of the ligand. The trimeric and tetrameric cyclobutane derivatives were reversely achieved by the photoinitiated [2+2] cycloaddition of the CP due to the favorable Schmidt's distance. More interestingly, a dynamic fluorescence shift was observed during the photo-oligomerization and heat-cycloreversion of the CP system.

18.
J Ultrasound Med ; 39(6): 1117-1123, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31814148

RESUMEN

OBJECTIVES: This study aimed to investigate the reliability of 3-dimensional (3D) ultrasound in screening for developmental dysplasia of the hip (DDH) by comparing the results with those of 2-dimensional (2D) ultrasound. METHODS: One hundred five infants who were younger than 6 months were enrolled in this study. All of the infants underwent 2D and 3D ultrasound scanning for DDH by novices and experts, and the images were graded by a lead expert. The scanning time and image grades were analyzed by Student t tests (P < .05). The consistency of the α angle measurement between the novices and experts was evaluated by the intraclass correlation coefficient (ICC). RESULTS: The 105 infants included 34 boys and 71 girls. On 2D scanning, there was agreement between the experts about the correct diagnosis, whereas in the novice group, 41 infants had misdiagnoses. There were no misdiagnoses with 3D scanning in either group. In the novice group, the mean image grades ± SD were 4.2 ± 1.3 (2D ultrasound) and 8.1 ± 0.7 (3D ultrasound; P < .05). In the expert group, the mean image grades were 7.4 ± 1.0 (2D ultrasound) and 8.2 ± 1.0 (3D ultrasound; P < .05). There was no statistically significant difference between the groups in the grades for 3D ultrasound (P = .83). The scanning time for 3D ultrasound was shorter than that for 2D ultrasound in both groups (P < .05). In the novice group, the ICC of the α angle between the 2D and 3D ultrasound results was 0.34, and in the expert group, it was 0.92. The ICCs were 0.35 and 0.84, respectively when comparing 2D and 3D ultrasound results in the groups. CONCLUSIONS: Three-dimensional ultrasound required less time and showed greater inter-rater reliability than 2D ultrasound for detecting DDH.


Asunto(s)
Displasia del Desarrollo de la Cadera/diagnóstico por imagen , Imagenología Tridimensional/métodos , Ultrasonografía/métodos , Femenino , Articulación de la Cadera/diagnóstico por imagen , Humanos , Lactante , Masculino , Reproducibilidad de los Resultados
19.
Oncol Lett ; 18(6): 5917-5922, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31788065

RESUMEN

Clinical value of ultrasonic imaging in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis was investigated. Eighty-nine patients who were diagnosed with hypopharyngeal cancer in Qilu Hospital of Shandong University (Qingdao) from January 2014 to June 2016 were retrospectively analyzed. Sixty-eight patients were diagnosed with hypopharyngeal cancer with cervical lymph node metastasis by pathological sections. Twenty-one patients did not have cervical lymph node metastasis. All the patients were diagnosed by palpation and ultrasound. The lymph node ultrasound images were quantified by computer, and the long/short diameter ratio, the maximum systolic velocity, blood flow resistance of the metastatic and non-metastatic patients were compared. The diagnostic efficacy of palpation and ultrasound was analyzed in the diagnosis of hypopharyngeal cancer with cervical lymph node metastasis. A correlation analysis was carried out between the image features of ultrasound and lymph node metastasis. The long/short diameter ratio, maximum systolic velocity and resistance index of patients with lymph node metastasis were significantly higher than those without lymph node metastasis, with a significant difference (P<0.05). Forty-one patients were diagnosed with lymph node metastasis by palpation, fifty-nine patients were diagnosed with lymph node metastasis by ultrasound. The sensitivity and diagnostic coincidence rate of ultrasound in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis were significantly higher than those of palpation (P<0.05). Statistically significant differences were observed in lymph node internal echo types, medullary echo characteristics, envelope definition, and blood flow distribution characteristics between the metastasis group and the non-metastasis group (P<0.05). Lymph node internal echo was heterogeneous. There was no medulla, and the disordered blood flow in the lymph node predicted lymph node metastasis. Preoperative ultrasound has a high diagnostic value in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis. The diagnostic results of preoperative ultrasound can be used as a reference for the diagnosis and treatment of hypopharyngeal cancer with cervical lymph node metastasis.

20.
Int J Mol Sci ; 20(9)2019 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-31067654

RESUMEN

As a gaseous biological signaling molecule, nitric oxide (NO) regulates many physiological processes in plants. Over the last decades, this low molecular weight compound has been identified as a key signaling molecule to regulate plant stress responses, and also plays an important role in plant development. However, elucidation of the molecular mechanisms for NO in leaf development has so far been limited due to a lack of mutant resources. Here, we employed the NO-deficient mutant nia1nia2 to examine the role of NO in leaf development. We have found that nia1nia2 mutant plants displayed very different leaf phenotypes as compared to wild type Col-0. Further studies have shown that reactive oxygen species (ROS) levels are higher in nia1nia2 mutant plants. Interestingly, ROS-related enzymes ascorbate peroxidase (APX), catalases (CAT), and peroxidases (POD) have shown decreases in their activities. Our transcriptome data have revealed that the ROS synthesis gene RBOHD was enhanced in nia1nia2 mutants and the photosynthesis-related pathway was impaired, which suggests that NO is required for chloroplast development and leaf development. Together, these results imply that NO plays a significant role in plant leaf development by regulating ROS homeostasis.


Asunto(s)
Arabidopsis/metabolismo , Homeostasis , Óxido Nítrico/metabolismo , Hojas de la Planta/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Nitrato-Reductasa/genética , Nitrato-Reductasa/metabolismo , Fotosíntesis , Hojas de la Planta/crecimiento & desarrollo
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