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1.
Cancer Lett ; : 216938, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38734160

RESUMEN

Fewer than 5% glioblastoma (GBM) patients survive over five years and are termed long-term survivors (LTS), yet their molecular background is unclear. The present cohort included 72 isocitrate dehydrogenase (IDH)-wildtype GBM patients, consisting of 35 LTS and 37 short-term survivors (STS), and we employed whole exome sequencing, RNA-seq and DNA methylation array to delineate this largest LTS cohort to date. Although LTS and STS demonstrated analogous clinical characters and classical GBM biomarkers, CASC5 (P = 0.002) and SPEN (P = 0.013) mutations were enriched in LTS, whereas gene-to-gene fusions were concentrated in STS (P = 0.007). Importantly, LTS exhibited higher tumor mutation burden (P < 0.001) and copy number (CN) increase (P = 0.013), but lower mutant-allele tumor heterogeneity score (P < 0.001) and CN decrease (P = 0.026). Additionally, LTS demonstrated hypermethylated genome (P < 0.001) relative to STS. Differentially expressed and methylated genes both enriched in olfactory transduction. Further, analysis of the tumor microenvironment revealed higher infiltration of M1 macrophages (P = 0.043), B cells (P = 0.016), class-switched memory B cells (P = 0.002), central memory CD4+ T cells (P = 0.031) and CD4+ Th1 cells (P = 0.005) in LTS. We also separately analyzed a subset of patients who were methylation class-defined GBM, contributing 70.8% of the entire cohort, and obtained similar results relative to prior analyses. Finally, we demonstrated that LTS and STS could be distinguished using a subset of molecular features. Taken together, the present study delineated unique molecular attributes of LTS GBM.

2.
Immunol Invest ; : 1-22, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622991

RESUMEN

Osteoarthritis (OA) is now widely acknowledged as a low-grade inflammatory condition, in which the intrinsic immune system plays a significant role in its pathogenesis. While the involvement of macrophages and T cells in the development of OA has been extensively reviewed, recent research has provided mounting evidence supporting the crucial contribution of NK cells in both the initiation and advancement of OA. Accumulated evidence has emerged in recent years indicating that NK cells play a critical role in OA development and progression. This review will outline the ongoing understanding of the utility of NK cells in the etiology of OA, focusing on how NK cells interact with chondrocytes, synoviocytes, osteoclasts, and other immune cells to influence the course of OA disease.

3.
Int J Pharm ; 655: 124028, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38518871

RESUMEN

Ovarian cancer is a malignant tumor that seriously endangers the lives of women, with chemotherapy being the primary clinical treatment. However, chemotherapy encounters the problem of generating multidrug resistance (MDR), mainly due to drug efflux induced by P-glycoprotein (P-gp), which decreases intracellular accumulation of chemotherapeutic drugs. The drugs efflux mediated by P-gp requires adenosine triphosphate (ATP) hydrolysis to provide energy. Therefore, modulating energy metabolism pathways and inhibiting ATP production may be a potential strategy to reverse MDR. Herein, we developed a PTX-ATO-QUE nanoparticle (PAQNPs) based on a PLGA-PEG nanoplatform capable of loading the mitochondrial oxidative phosphorylation (OXPHOS) inhibitor atovaquone (ATO), the glycolysis inhibitor quercetin (QUE), and the chemotherapeutic drug paclitaxel (PTX) to reverse MDR by inhibiting energy metabolism through multiple pathways. Mechanistically, PAQNPs could effectively inhibit the OXPHOS and glycolytic pathways of A2780/Taxol cells by suppressing the activities of mitochondrial complex III and hexokinase II (HK II), respectively, ultimately decreasing intracellular ATP levels in tumor cells. Energy depletion can effectively inhibit cell proliferation and reduce P-gp activity, increasing the chemotherapeutic drug PTX accumulation in the cells. Moreover, intracellular reactive oxygen species (ROS) is increased with PTX accumulation and leads to chemotherapy-resistant cell apoptosis. Furthermore, PAQNPs significantly inhibited tumor growth in the A2780/Taxol tumor-bearing NCG mice model. Immunohistochemical (IHC) analysis of tumor tissues revealed that P-gp expression was suppressed, demonstrating that PAQNPs are effective in reversing MDR in tumors by inducing energy depletion. In addition, the safety study results, including blood biochemical indices, major organ weights, and H&E staining images, showed that PAQNPs have a favorable in vivo safety profile. In summary, the results suggest that the combined inhibition of the two energy pathways, OXPHOS and glycolysis, can enhance chemotherapy efficacy and reverse MDR in ovarian cancer.


Asunto(s)
Antineoplásicos , Nanopartículas , Neoplasias Ováricas , Humanos , Femenino , Ratones , Animales , Paclitaxel , Neoplasias Ováricas/patología , Atovacuona/farmacología , Atovacuona/uso terapéutico , Quercetina/farmacología , Quercetina/uso terapéutico , Línea Celular Tumoral , Resistencia a Antineoplásicos , Resistencia a Múltiples Medicamentos , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Metabolismo Energético , Adenosina Trifosfato/metabolismo
5.
Artículo en Inglés | MEDLINE | ID: mdl-37964172

RESUMEN

Silymarin (SM) exhibits clinical efficacy in treating liver injuries, cirrhosis, and chronic hepatitis. However, its limited water solubility and low bioavailability hinder its therapeutic potential. The primary objective of this study was to compare the in vitro and in vivo characteristics of the four distinct SM solubilization systems, namely SM solid dispersion (SM-SD), SM phospholipid complex (SM-PC), SM sulfobutyl ether-ß-cyclodextrin inclusion complex (SM-SBE-ß-CDIC) and SM self-microemulsifying drug delivery system (SM-SMEDDS) to provide further insights into their potential for enhancing the solubility and bioavailability of SM. The formation of SM-SD, SM-PC, and SM-SBE-ß-CDIC was thoroughly characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffractometry (PXRD) techniques to analyze the changes in their microscopic structure, molecular structure, and crystalline state. The particle size and polydispersity index (PDI) of SM-SMEDDS were 71.6 ± 1.57 nm, and 0.13 ± 0.03, respectively. The self-emulsifying time of SM-SMEDDS was 3.0 ± 0.3 min. SM-SMEDDS exhibited an improved in vitro dissolution rate and demonstrated the highest relative bioavailability compared to pure SM, SM-SD, SM-PC, SM-SBE-ß-CDIC, and Legalon®. Consequently, SMEDDS shows promise as a drug delivery system for orally administered SM, offering enhanced solubility and bioavailability.

6.
Anal Chim Acta ; 1279: 341789, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37827683

RESUMEN

There has been significant interest in the preparation and versatile applications of carbon dots (CDs) due to their immense potential value in sensors and imaging. In this work, silicon-doped green carbon dots (Si-CDs) with high quantum yield and rich epoxypropyl were effectively synthesized. Given the clinical diagnostic importance of abnormal levels of tyrosinase (TYR), sensitive detection of TYR is significant for clinical research. A fluorescence signal-off strategy with Si-CDs as probe was constructed to determine TYR based on the oxidation of dopamine by TYR. The detection ranges of this method were 0.01-1.5 and 10-30 U/mL with the detection limit of 0.0046 U/mL, the lower limit of quantification (LLOQ) was 0.01 U/mL, and TYR was successfully and accurately monitored in human serum. Additionally, due to the role of lysosomes in cellular regulatory processes, including TYR levels and fluorescence stability characteristics of Si-CDs in acidic conditions, it was envisaged to use Si-CDs as probe to establish real-time monitoring of lysosomes. According to fluorescence colocation analysis, Si-CDs had intrinsic lysosomal targeting ability to HepG2 and L-02 (with Pearson correlation coefficients were 0.90 and 0.91, respectively). The targeting of Si-CDs to lysosomes was due to the acidophilic effect of the epoxypropyl on its surface.


Asunto(s)
Monofenol Monooxigenasa , Puntos Cuánticos , Humanos , Carbono , Dopamina , Oxidación-Reducción , Colorantes Fluorescentes , Nitrógeno
7.
RSC Adv ; 13(35): 24460-24465, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37588978

RESUMEN

A series of chiral bifunctional organocatalysts were prepared and used for enantioselective synthesis of 3-substituted isoindolinones from 2-formylarylnitriles and malonates through aldol-cyclization rearrangement tandem reaction in excellent yields and enantioselectivites (up to 87% yield and 95% ee) without recrystallization. In this investigation, we found that chiral tertiary-amine catalysts with a urea group can afford 3-substituted isoindolinones both in higher yields (87% vs. 77%) and enantioselectivities (95% ee vs. 46% ee) than chiral bifunctional phase-transfer catalysts.

8.
Biomed Pharmacother ; 166: 115316, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37572638

RESUMEN

Melanoma is a highly aggressive form of skin cancer with limited therapeutic options. Chemo-photothermal combination therapy has demonstrated potential for effectively treating melanoma, and transdermal administration is considered the optimal route for treating skin diseases due to its ability to bypass first-pass metabolism and enhance drug concentration. However, the stratum corneum presents a formidable challenge as a significant barrier to drug penetration in transdermal drug delivery. Lipid-nanocarriers, particularly cubosomes, have been demonstrated to possess significant potential in augmenting drug permeation across the stratum corneum. Herein, cubosomes co-loaded with doxorubicin (DOX, a chemotherapeutic drug) and indocyanine green (ICG, a photothermal agent) (DOX-ICG-cubo) transdermal drug delivery system was developed to enhance the therapeutic efficiency of melanoma by improving drug permeation. The DOX-ICG-cubo showed high encapsulation efficiency of both DOX and ICG, and exhibited good stability under physiological conditions. In addition, the unique cubic structure of the DOX-ICG-cubo was confirmed through transmission electron microscopy (TEM) images, polarizing microscopy, and small angle X-ray scattering (SAXS). The DOX-ICG-cubo presented high photothermal conversion efficiency, as well as pH and thermo-responsive DOX release. Notably, the DOX-ICG-cubo exhibited enhanced drug permeation efficiency, good biocompatibility, and improved in vivo anti-melanoma efficacy through the synergistic effects of chemo-photothermal therapy. In conclusion, DOX-ICG-cubo presented a promising strategy for melanoma treatment.


Asunto(s)
Hipertermia Inducida , Melanoma , Nanopartículas , Humanos , Verde de Indocianina , Fototerapia/métodos , Terapia Fototérmica , Administración Cutánea , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Doxorrubicina/farmacología , Melanoma/tratamiento farmacológico , Nanopartículas/química , Línea Celular Tumoral
9.
Adv Healthc Mater ; 12(19): e2203019, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37104840

RESUMEN

Although the combination of chemotherapy and immune checkpoint inhibitors (ICIs) can treat triple-negative breast cancer (TNBC), the severe effects of chemotherapy on immune cells significantly reduce the efficacy of the ICIs. Photodynamic therapy (PDT) with high selectivity is an alternative to chemotherapy that can also effectively treat hypoxic TNBC. However, high levels of immunosuppressive cells, and low infiltration of cytotoxic T lymphocytes (CTLs) limit the efficacy of PDT combined with ICIs. This study aims to evaluate the role of drug self-delivery nanocubes (ATO/PpIX-SMN) combined with anti-PD-L1 in TNBC treatment. Anti-malarial atovaquone (ATO) enhances protoporphyrin IX (PpIX)-mediated PDT-induced immunogenic cell death and downregulates tumor Wnt/ß-catenin signaling. Furthermore, the nanocubes combined with anti-PD-L1, which synergistically induce maturation of dendritic cells, promote infiltration of CTLs, reduce regulatory T cells, and significantly activate the host immune system, thus treating primary and distal tumors. This work demonstrates that ATO/PpIX-SMN can enhance the response rate of anti-PD-L1 in TNBC treatment via O2 -economized photodynamic-downregulating Wnt/ß-catenin signaling.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Línea Celular Tumoral , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , beta Catenina/metabolismo , Vía de Señalización Wnt , Inmunoterapia
10.
J Pharm Sci ; 112(4): 1119-1129, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36596394

RESUMEN

The encapsulation efficiency (EE) of hydrophobic drug into cubosomes was high by conventional methods, while poor for the hydrophilic drug. In this study, a remote loading method based on transmembrane pH-gradient was applied to prepare hydrophilic drug loaded cubosomes. Several hydrophilic drugs were selected and studied. Results showed just part of the investigated drugs were successfully loaded into cubosomes by the remote loading method, whereas all the drugs failed to be encapsulated by the high-pressure homogenization method. The EE based on remote loading method was affected by the solubility, LogP, number of rings, and polarizability of the drug independent of the number of hydrogen acceptor and hydrogen donor. And the drugs that had high EE by remote loading method were BCS class 1 or 2. In addition, the EE base on remote loading method was significantly affected by the external water pH of cubosomes and drug concentration. The size of drug-loaded cubosomes by remote loading method mainly depended on the pre-formed blank cubosomes, which was bigger than that by high-pressure homogenization method. The preparation method affected the liquid crystalline structure of acidic drug loaded cubosomes, while showed no obvious effect on that of basic drug loaded cubosomes. The release of drug was susceptible to the pH of release medium independent of the preparation method. The drug-loaded cubosomes prepared by different method all showed favorable stability during storage. The remote loading method was a promising approach for the efficient encapsulation of hydrophilic drug into cubosomes. This study laid a foundation for the application of remote loading method on the preparation of hydrophilic drug loaded cubosomes.


Asunto(s)
Cristales Líquidos , Nanopartículas , Solubilidad , Cristales Líquidos/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Nanopartículas/química
11.
Oxid Med Cell Longev ; 2022: 3243647, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36211828

RESUMEN

Pancreatic ductal adenocarcinoma (PDA) is often concomitant with diabetes mellitus, which mainly manifests as an increased blood glucose level. Previous studies revealed that diabetic status reduced the survival and blunted gemcitabine sensitivity in PDA patients. This study is aimed at analyzing the mechanism of elevated gemcitabine resistance and cancer invasion ability under high glucose environment. We selected 129 patients with 22 surgical resected samples from 2015 to 2021, who underwent pancreatic surgery in Huashan Hospital. The gene expression and clinical data of PDA were obtained from The Cancer Genome Atlas (TCGA) website and were analyzed by R software. Cell viability assays and flow cytometry were applied to detect gemcitabine sensitivity and apoptosis levels in pancreatic cancer cells. Wound healing and Transwell tests were used to analyze the invasion and metastasis of cancer cells. Streptozotocin (STZ) was used to establish a hyperglycemic mouse model for the in vivo study. In this study, diabetic PDA gemcitabine users showed reduced survival compared to euglycemic PDA gemcitabine users. Clinical samples and laboratory studies revealed that MMP-3 expression was associated with glucose concentration and diabetic status. Elevated MMP-3 expression was positively related to cancer invasion and gemcitabine resistance in PDA cells and gemcitabine resistant PDA cells. Blocking MMP-3 expression inhibited gemcitabine resistance and cancer progression in cellular and animal models. MMP-3 was closely related to the expression of RRM1, a gemcitabine metabolism-related gene. Reactive oxygen species (ROS) level increased under higher glucose concentrations and was mediated by NOX4. ROS determined the MMP-3 expression in pancreatic cancer cells. Inhibiting NOX4 expression effectively suppressed MMP-3 expression, gemcitabine resistance, and cancer invasion. In conclusion, a high glucose environment induces gemcitabine resistance and cancer invasion via ROS/MMP-3 signaling pathway. MMP-3 can be a potential novel target for suppressing gemcitabine resistance and invasion in PDA.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Glucemia , Carcinoma Ductal Pancreático/tratamiento farmacológico , Línea Celular Tumoral , Desoxicitidina/análogos & derivados , Resistencia a Antineoplásicos/genética , Metaloproteinasa 3 de la Matriz/metabolismo , Ratones , Neoplasias Pancreáticas/metabolismo , Especies Reactivas de Oxígeno , Transducción de Señal , Estreptozocina , Gemcitabina , Neoplasias Pancreáticas
12.
Front Oncol ; 12: 770628, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35372056

RESUMEN

Glioma is one of the most deadly types of brain cancer. As it is highly invasive, the prognosis for glioma patients remains dismal, with median survival rarely exceeding 16 months. Thus, developing a new prognostic biomarker for glioma and investigating its molecular mechanisms is necessary for the development of an efficient treatment strategy. In this study, we analyzed a cohort of 1,131 glioma patients using RNA-seq data from The Cancer Genome Atlas (TCGA project) and Gene Expression Omnibus (GSE4290 and GSE16011 datasets), and validated the results using the RNA-seq data of 1,018 gliomas from the Chinese Glioma Genome Atlas (CGGA project). We used the R language as the main tool for statistical analysis and data visualization. We found that NCAPG, a mitosis-associated chromosomal condensing protein, is highly expressed in glioma tissues. Furthermore, the expression of NCAPG increased significantly with the increase in tumor grade, and high NCAPG expression was found to be a predictor of poor overall survival in glioma patients (P < 0.001). This result shows that NCAPG expression could be an independent prognostic factor. Importantly, when the expression of NCAPG was knocked down, the CCK-8 assay revealed that the proliferation of glioma cells (LN-229 and T98G cell lines) decreased significantly compared with the control group. In addition, the healing rates of these cells were significantly lower in the si-NCAPG group than in the control group (P < 0.001). We then used the CIBERSORT algorithm to analyze the expression levels of 22 subpopulations of immune cells and found that NCAPG was significantly negatively correlated with natural killer cell activation. In addition, it was positively correlated with MHC-I molecules and ADAM17. Our study is first in comprehensively describing the high expression of NCAPG in glioma. It also shows that NCAPG can function as an independent prognostic predictor of glioma, and that targeting NCAPG can be a new strategy for the treatment of glioma patients.

13.
Int J Pharm ; 621: 121775, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35489603

RESUMEN

Photodynamic therapy (PDT) shows very high potential for the clinical treatment of triple-negative breast cancer. However, the efficacy of PDT is significantly weakened by tumor hypoxia, the relatively high intracellular glutathione levels and the active proliferation of cancer cells. To address these issues, we developed a novel drug self-delivery nanorod (defined as AINRs) through the hydrophobic interaction among the mitochondrial complex III inhibitor (atovaquone, ATO), the photosensitizer (indocyanine green, ICG) and the dispersion stabilizer (distearoyl phosphoethanolamine-polyethylene glycol 2000, DSPE-PEG 2000). The AINRs showed a rod-like morphology with a mean diameter of 120.6 ± 5.4 nm, a zeta potential of -26.35 ± 1.63 mV and a significantly high drug loading rate of 93.48%. The results of in vitro cell experiments involving triple-negative breast cancer cell lines (4T1 cells and MDA-MB-231 cells) indicated that the AINRs could effectively block the oxidative phosphorylation of cancer cells through the inhibition of mitochondrial complex III, which results in the reduction of endogenous oxygen consumption and the decrease of the intracellular ATP level. The reduction of ATP content further inhibited the glutathione synthesis and arrested the cell cycle at the S-phase, which results in enhanced in vitro PDT efficacy of ICG. The results of in vivo antitumor activity in 4T1-bearing mice showed that the tumor growth inhibition rate of the AINRs with near-infrared laser irradiation (NIR) was greater than 90%, whereas the tumor growth inhibition rates of the AINRs without NIR, ICG with NIR and doxorubicin (3 mg/kg) were only 31.68%, 61.15% and 24.59%, respectively. In addition, the results of safety studies, including body weights, biochemical indicators and H&E staining images of the main organs demonstrated the security of the AINRs. In summary, this study showed that the oxidative phosphorylation inhibition of triple-negative breast cancer was a safe and effective method to enhance its PDT efficacy.


Asunto(s)
Nanotubos , Fotoquimioterapia , Neoplasias de la Mama Triple Negativas , Adenosina Trifosfato , Animales , Línea Celular Tumoral , Complejo III de Transporte de Electrones , Glutatión , Humanos , Verde de Indocianina , Ratones , Nanotubos/química , Fosforilación Oxidativa , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología
14.
Cancer Cell Int ; 21(1): 32, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413403

RESUMEN

BACKGROUND: Triple-negative breast cancer (TNBC) is the most challenging breast cancer subtype to treat, because it is so aggressive with shorter survival. Chemotherapy remains the standard treatment due to the lack of specific and effective molecular targets. The aim of the present study is to investigate the potential roles of A Disintegrin and Metalloproteinase 10 (ADAM10) on TNBC cells and the effects of combining ADAM10 expression and neoadjuvant chemotherapy treatment (NACT) to improve the overall survival in breast cancer patients. METHODS: Using a series of breast cancer cell lines, we measured the expression of ADAM10 and its substrates by quantitative real-time PCR assay (qRT-PCR) and western blot analysis. Cell migration and invasion, cell proliferation, drug sensitivity assay, cell cycle and apoptosis were conducted in MDA-MB-231 cells cultured with ADAM10 siRNA. The effect of ADAM10 down-regulation by siRNA on its substrates was assessed by western blot analysis. We performed immunohistochemical staining for ADAM10 in clinical breast cancer tissues in 94 patients receiving NACT. RESULTS: The active form of ADAM10 was highly expressed in TNBC cell lines. Knockdown of ADAM10 in MDA-MB-231 cells led to a significant decrease in cell proliferation, migration, invasion and the IC50 value of paclitaxel and adriamycin, while induced cell cycle arrest and apoptosis. And these changes were correlated with down-regulation of Notch signaling, CD44 and cellular prion protein (PrPc). In clinical breast cancer cases, a high ADAM10 expression in pre-NACT samples was strongly associated with poorer response to NACT and shorter overall survival. CONCLUSIONS: These data suggest the previously unrecognized roles of ADAM10 in contributing to the progression and chemo-resistance of TNBC.

15.
IEEE Trans Biomed Circuits Syst ; 13(6): 1583-1592, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31751285

RESUMEN

A dual-band dual-polarized wearable array is proposed, based on a miniaturized innovating button radiator topology. The diameter of the rigid button is only 19.5 mm (0.29 λ at 4.5 GHz), which optimizes the users' comfort, and makes it the smallest up to date in literature. The operational bands are 4.50-4.61 GHz and 5.04-5.50 GHz. The antenna thus covers the 4.5-4.6 unlicensed future 5th generation (5G) communication band for the internet of things (IoT), and the 5.1-5.5 GHz wireless local area network (WLAN) band, respectively. Two orthogonal linear polarizations are obtained in each band. A low mutual coupling between the button antenna elements (below -18 dB) and between the two ports within each element (below -20 dB) is achieved, guaranteeing a good diversity performance. The envelope correlation coefficient (ECC) and the specific absorption rate (SAR) performance are also analyzed. In order to demonstrate the robustness of the button antenna and to mimic realistic situations, a more complicated asymmetrical ground plane model of the button antenna is studied for the first time. A prototype of a two-element button array has been fabricated. The measurement results match well with the simulations. A 10-element button array is studied within the context of a 3-D channel model, taking into account the button element's radiation pattern. A high achievable spectral efficiency (SE) is obtained.


Asunto(s)
Tecnología Inalámbrica/instrumentación , Diseño de Equipo , Miniaturización , Dispositivos Electrónicos Vestibles
16.
Org Lett ; 21(21): 8641-8645, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31603341

RESUMEN

Convenient synthesis and useful application of a series of Josiphos-type binaphane ligands were described. The iridium complexes of these chiral diphosphines displayed excellent enantioselectivity and good reactivity in the asymmetric hydrogenation of challenging 1-aryl-substituted dihydroisoquinoline substrates (full conversions, up to >99% ee, 4000 TON). The use of 40% HBr (aqueous solution) as an additive dramatically improved the asymmetric induction of these catalysts. This transformation provided a highly efficient and enantioselective access to chiral 1-aryl-substituted tetrahydroisoquinolines, which were of great importance and common in natural products and biologically active molecules.

17.
RSC Adv ; 9(48): 27883-27887, 2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-35530461

RESUMEN

A one-pot, base-catalyzed, tandem grinding process involving carrying out aldol condensation and Michael addition in sequence to produce 3,4,5-trisubstituted isoxazoles from 3,5-dimethyl-4-nitroisoxazole, aromatic aldehydes and activated methylene compounds has been developed. In the presence of 10 mol% of pyrrolidine, aldol condensations of 3,5-dimethyl-4-nitroisoxazole with various aromatic aldehydes were performed with 3-10 minutes of grinding to provide 5-styryl-3-methyl-4-nitroisoxazoles in good to quantitative yields without further purification. Then, Michael additions between 5-styryl-3-methyl-4-nitroisoxazoles and activated methylene compounds (including ethyl 2-nitroacetate and alkyl 2-cyanoacetates) were carried out in the presence of 10 mol% of Et3N in the same mortar with 3-5 minutes of continuous grinding to produce 3,4,5-trisubstituted isoxazoles in good to excellent yields.

18.
Bioconjug Chem ; 29(4): 826-837, 2018 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-29316785

RESUMEN

Most nanodrugs are preprepared by encapsulating or loading the drugs with nanocarriers (e.g., dendrimers, liposomes, micelles, and polymeric nanoparticles). However, besides the low bioavailability and fast excretion of the nanodrugs in vivo, nanocarriers often exhibit in vitro and in vivo cytotoxicity, oxidative stress, and inflammation. Self-assembly is a ubiquitous process in biology where it plays important roles and underlies the formation of a wide variety of complex biological structures. Inspired by some cellular nanostructures (e.g., actin filaments, microtubules, vesicles, and micelles) in biological systems which are formed via molecular self-assembly, in recent decades, scientists have utilized self-assembly of oligomeric peptide under specific physiological or pathological environments to in situ construct nanodrugs for lesion-targeted therapies. On one hand, peptide-based nanodrugs always have some excellent intrinsic chemical (specificity, intrinsic bioactivity, biodegradability) and physical (small size, conformation) properties. On the other hand, stimuli-regulated intracellular self-assembly of nanodrugs is quite an efficient way to accumulate the drugs in lesion location and can realize an in situ slow release of the drugs. In this review article, we provided an overview on recent design principles for intracellular peptide self-assembly and illustrate how these principles have been applied for the in situ preparation of nanodrugs at the lesion location. In the last part, we list some challenges underlying this strategy and their possible solutions. Moreover, we envision the future possible theranostic applications of this strategy.


Asunto(s)
Biomimética/métodos , Nanomedicina/métodos , Nanoestructuras/química , Nanoestructuras/uso terapéutico , Péptidos/química , Péptidos/uso terapéutico , Animales , Humanos
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