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1.
Int J Biol Macromol ; 275(Pt 2): 133629, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38964682

RESUMEN

In this study, we investigated the use of deep eutectic solvents (DESs) at different molar ratios and temperatures as a green and efficient approach for microfibers (MFs) extraction. Our approach entailed the utilization of Firmiana simplex bark (FSB) fibers, enabling the production of different dimensions of FSB microfibers (FSBMFs) by combining DES pretreatment and mechanical disintegration technique. The proposed practice demonstrates the simplicity and effectiveness of the method. The morphology of the prepared microfibers was studied using the Scanning electron microscopic (SEM) technique. Additionally, the results revealed that the chemical and mechanical treatments did not significantly alter the well-preserved cellulose structure of microfibers, and a crystallinity index of 56.6 % for FSB fibers and 63.8 % for FSBMFs was observed by X-ray diffraction (XRD) analysis. Furthermore, using the freeze-drying technique, FSBMFs in water solutions produced effective aerogels for air purification application. In comparison to commercial mask (CM), FSBMF aerogels' superior hierarchical cellular architectures allowed them to attain excellent filtration efficiencies of 94.48 % (PM10) and 91.51 % (PM2.5) as well as excellent degradation properties were analyzed. The findings show that FSBMFs can be extracted from Firmiana simplex bark, a natural cellulose-rich material, using DES for environmentally friendly aerogel preparation and applications.


Asunto(s)
Biomasa , Corteza de la Planta , Corteza de la Planta/química , Disolventes Eutécticos Profundos/química , Celulosa/química , Geles/química , Difracción de Rayos X , Solventes/química
2.
J Med Chem ; 67(14): 11989-12011, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38959216

RESUMEN

The P2Y14 receptor has been proven to be a potential target for IBD. Herein, we designed and synthesized a series of 4-amide-thiophene-2-carboxyl derivatives as novel potent P2Y14 receptor antagonists based on the scaffold hopping strategy. The optimized compound 39 (5-((5-fluoropyridin-2-yl)oxy)-4-(4-methylbenzamido)thiophene-2-carboxylic acid) exhibited subnanomolar antagonistic activity (IC50: 0.40 nM). Moreover, compound 39 demonstrated notably improved solubility, liver microsomal stability, and oral bioavailability. Fluorescent ligand binding assay confirmed that 39 has the binding ability to the P2Y14 receptor, and molecular dynamics (MD) simulations revealed the formation of a unique intramolecular hydrogen bond (IMHB) in the binding conformation. In the experimental colitis mouse model, compound 39 showed a remarkable anti-IBD effect even at low doses. Compound 39, with a potent anti-IBD effect and favorable druggability, can be a promising candidate for further research. In addition, this work lays a strong foundation for the development of P2Y14 receptor antagonists and the therapeutic strategy for IBD.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Receptores Purinérgicos P2 , Tiofenos , Animales , Tiofenos/farmacología , Tiofenos/síntesis química , Tiofenos/química , Tiofenos/uso terapéutico , Humanos , Ratones , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Receptores Purinérgicos P2/metabolismo , Relación Estructura-Actividad , Antagonistas del Receptor Purinérgico P2/farmacología , Antagonistas del Receptor Purinérgico P2/química , Antagonistas del Receptor Purinérgico P2/síntesis química , Antagonistas del Receptor Purinérgico P2/uso terapéutico , Masculino , Descubrimiento de Drogas , Amidas/química , Amidas/farmacología , Amidas/síntesis química , Amidas/uso terapéutico , Microsomas Hepáticos/metabolismo , Simulación de Dinámica Molecular , Colitis/tratamiento farmacológico
3.
Cell Biol Toxicol ; 40(1): 45, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38864940

RESUMEN

MALT1 has been implicated as an upstream regulator of NF-κB signaling in immune cells and tumors. This study determined the regulatory mechanisms and biological functions of MALT1 in non-small cell lung cancer (NSCLC). In cell culture and orthotopic xenograft models, MALT1 suppression via gene expression interference or protein activity inhibition significantly impaired malignant phenotypes and enhanced radiation sensitivity of NSCLC cells. CSN5, the core subunit of COP9 signalosome, was firstly verified to stabilize MALT1 via disturbing the interaction with E3 ligase FBXO3. Loss of FBXO3 in NSCLC cells reduced MALT1 ubiquitination and promoted its accumulation, which was reversed by CSN5 interference. An association between CSN5/FBXO3/MALT1 regulatory axis and poor prognosis in NSCLC patients was identified. Our findings revealed the detail mechanism of continuous MALT1 activation in NF-κB signaling, highlighting its significance as predictor and potential therapeutic target in NSCLC.


Asunto(s)
Complejo del Señalosoma COP9 , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas , FN-kappa B , Transducción de Señal , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas/metabolismo , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Humanos , Complejo del Señalosoma COP9/metabolismo , Complejo del Señalosoma COP9/genética , FN-kappa B/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Animales , Línea Celular Tumoral , Ratones , Ratones Desnudos , Ubiquitinación , Péptido Hidrolasas/metabolismo , Péptido Hidrolasas/genética , Progresión de la Enfermedad , Ratones Endogámicos BALB C , Femenino , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Péptidos y Proteínas de Señalización Intracelular
4.
J Dermatol Sci ; 114(1): 24-33, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38448340

RESUMEN

BACKGROUND: The unfolded protein response (UPR) is one of the cytoprotective mechanisms against various stresses and essential for the normal function of skin. Skin injury caused by ionizing radiation (IR) is a common side effect of radiotherapy and it is unclear how UPR affects IR-induced skin injury. OBJECTIVES: To verify the effect of UPR on IR-induced DNA damage in keratinocytes and the relation between an endoplasmic reticulum (ER) protein KTN1 and UPR. METHODS: All experiments were performed on keratinocytes models: HaCaT and HEK-A. ER lumen and the expression levels of KTN1 and UPR pathway proteins (PERK, IRE1α and ATF6) were examined by transmission electron microscopy and immunoblotting, respectively. 4-PBA, an UPR inhibitor, was used to detected its effects on DNA damage and cell proliferation. Subsequently, the effects of KTN1 deletion on UPR, DNA damage and cell proliferation after IR were detected. Tunicamycin was used to reactivate UPR and then we examined its effects on DNA damage. RESULTS: UPR was activated by IR in keratinocytes. Inhibition of UPR aggravated DNA damage and suppressed cell proliferation after IR. KTN1 expression was upregulated by IR and KTN1 depletion reduced ER expansion and the expression of UPR-related proteins. Moreover, KTN1 depletion aggravated DNA damage and suppressed cell proliferation after IR could reversed by reactivation of UPR. CONCLUSION: KTN1 deletion aggravates IR-induced keratinocyte DNA damage via inhibiting UPR. Our findings provide new insights into the mechanisms of keratinocytes in response to IR-induced damage.


Asunto(s)
Proliferación Celular , Daño del ADN , Células HaCaT , Queratinocitos , Radiación Ionizante , Respuesta de Proteína Desplegada , Humanos , Línea Celular , Proliferación Celular/efectos de la radiación , Proliferación Celular/efectos de los fármacos , Daño del ADN/efectos de la radiación , Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/efectos de la radiación , Retículo Endoplásmico/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de la radiación , Estrés del Retículo Endoplásmico/efectos de los fármacos , Queratinocitos/efectos de la radiación , Queratinocitos/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Piel/efectos de la radiación , Piel/patología , Piel/citología , Piel/efectos de los fármacos , Piel/metabolismo , Respuesta de Proteína Desplegada/efectos de la radiación , Respuesta de Proteína Desplegada/efectos de los fármacos
5.
Microbiol Spectr ; 12(1): e0109023, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38018973

RESUMEN

IMPORTANCE: HAdV-3, -7, and -55 are the predominant types causing acute respiratory disease outbreaks and can lead to severe and fatal pneumonia in children and adults. In recent years, emerging or re-emerging strains of HAdV-7 and HAdV-55 have caused multiple outbreaks globally in both civilian and military populations, drawing increased attention. Clinical studies have reported that HAdV-7 and HAdV-55 cause more severe pneumonia than HAdV-3. This study aimed to investigate the mechanisms explaining the higher severity of HAdV-7 and HAdV-55 infection compared to HAdV-3 infection. Our findings provided evidence linking the receptor-binding protein fiber to stronger infectivity of the strains mentioned above by comparing several fiber-chimeric or fiber-replaced adenoviruses. Our study improves our understanding of adenovirus infection and highlights potential implications, including in novel vector and vaccine development.


Asunto(s)
Infecciones por Adenovirus Humanos , Adenovirus Humanos , Neumonía , Infecciones del Sistema Respiratorio , Niño , Adulto , Humanos , Virulencia
6.
Biomater Sci ; 11(16): 5663-5673, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37432672

RESUMEN

Obesity has become a worldwide public health problem and continues to be one of the leading causes of chronic diseases. Obesity treatment is challenged by large drug doses, high administration frequencies and severe side effects. Herein, we propose an antiobesity strategy through the local administration of HaRChr fiber rods loaded with chrysin and grafted with hyaluronic acid and AtsFRk fiber fragments loaded with raspberry ketone and grafted with adipocyte target sequences (ATSs). The hyaluronic acid grafts double the uptake levels of HaRChr by M1 macrophages to promote phenotype transformation from M1 to M2 through upregulating CD206 and downregulating CD86 expressions. ATS-mediated targeting and sustained release of raspberry ketone from AtsFRk increase the secretion of glycerol and adiponectin, and Oil red O staining shows much fewer lipid droplets in adipocytes. The combination treatment with AtsFRk and the conditioned media from HaRChr-treated macrophages elevates adiponectin levels, suggesting that M2 macrophages may secrete anti-inflammatory factors to stimulate adipocytes to produce adiponectin. Diet-induced obese mice showed significant weight losses of inguinal (49.7%) and epididymal (32.5%) adipose tissues after HaRChr/AtsFRk treatment, but no effect was observed on food intake. HaRChr/AtsFRk treatment reduces adipocyte volumes, lowers serum levels of triglycerides and total cholesterol and restores adiponectin levels to those of normal mice. In the meantime, HaRChr/AtsFRk treatment significantly elevates the gene expression of adiponectin and interleukin-10 and downregulates tissue necrosis factor-α expression in the inguinal adipose tissues. Thus, local injection of cell-targeting fiber rods and fragments demonstrates a feasible and effective antiobesity strategy through improving lipid metabolism and normalizing the inflammatory microenvironment.


Asunto(s)
Adiponectina , Lipólisis , Animales , Ratones , Adiponectina/metabolismo , Adiponectina/farmacología , Adiponectina/uso terapéutico , Ácido Hialurónico/farmacología , Tejido Adiposo/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/etiología , Obesidad/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Ratones Endogámicos C57BL
7.
J Org Chem ; 88(15): 10647-10654, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37470361

RESUMEN

A new approach to oxazolidines and dihydroxazines was developed by regioselective cyclization of α-aminated ketones under transition metal-free conditions. Oxazolidine derivatives were generated in the presence of chloro benziodoxole and TFA, while dihydroxazines were formed without a hypervalent iodine reagent. The reaction was performed under room temperature and gave the products in good to excellent yields.

8.
Comput Struct Biotechnol J ; 20: 3755-3763, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35891783

RESUMEN

Background: MicroRNA (miRNA) regulates gene expression posttranscriptionally, and some of them function in tumor suppression and can be used in drug development. As a result, identifying and screening miRNAs that suppress tumors would be a significant addition to tumor treatment. Methods: In this study, we analyzed the miRNA expression profile of colorectal cancer (CRC), constructed a negative regulatory network of the miRNA-target genes, and identified miR-4469 as one of the key tumor suppressors miRNAs. We analyzed the expression and survival of miR-4469 in pan-cancer, experimentally verified the expression level of miR-4469 in CRC cells and the effect on CRC cell proliferation and migration. We screened miR-4469 target genes for enrichment analysis and immune cell infiltration analysis and validated target gene expression to clarify the regulatory mechanisms involved in miR-4469. Results: miR-4469 was more highly expressed in normal colorectum tissues compared to CRC tissues and correlated with survival time in patients with multiple cancers. It was shown that miR-4469 was highly expressed in normal colon cells and miR-4469 expression could inhibit the proliferation and migration of CRC cells. In addition, studies on the mechanism showed that miR-4469 function is mainly related to the regulation of inflammatory cell infiltration, and the key target genes of miR-4469 in this process are SLC2A3, FGR, PLEKHO2, and MYO1F. Conclusion: miR-4469 is a tumor suppressor in CRC, and its regulatory mechanism mainly affects the infiltration of inflammatory cells in the cancer tissue.

9.
Front Cell Dev Biol ; 10: 845048, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309901

RESUMEN

Colorectal cancer (CRC) is a malignant tumor with the second highest morbidity and the third highest mortality in the world, while the therapeutic options of targeted agents remain limited. Here, mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1), known as the upstream of the NF-κB signaling pathway, was identified to be highly upregulated in CRC tumors and cell lines. Furthermore, the downregulation of MALT1 or inhibition of its proteolytic function by MI-2 suppressed the cell proliferation and migration of CRC cells. In vivo, suppressing the MALT1 expression or its proteasome activity effectively reduced the size of the subcutaneous tumor in nude mice. Mechanistically, miR-375 and miR-365a-3p were identified to inhibit NF-κB activation via targeting MALT1. Overall, our results highlight that a novel regulatory axis, miRNA-MALT1-NF-κB, plays a vital role in the progression of CRC and provides novel and hopeful therapeutic targets for clinical treatment.

10.
Cell Death Dis ; 12(11): 995, 2021 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-34689164

RESUMEN

Depletion of kinectin1 (KTN1) provides a potential strategy for inhibiting tumorigenesis of cutaneous squamous cell carcinoma (cSCC) via reduction of epidermal growth factor receptor (EGFR) protein levels. Yet, the underlying mechanisms of KTN1 remain obscure. In this study, we demonstrate that KTN1 knockdown induces EGFR degradation in cSCC cells by promoting the ubiquitin-proteasome system, and that this effect is tumor cell-specific. KTN1 knockdown increases the expression of CCDC40, PSMA1, and ADRM1 to mediate tumor suppressor functions in vivo and in vitro. Mechanistically, c-Myc directly binds to the promoter region of CCDC40 to trigger the CCDC40-ADRM1-UCH37 axis and promote EGFR deubiquitination. Furthermore, KTN1 depletion accelerates EGFR degradation by strengthening the competitive interaction between PSMA1 and ADRM1 to inhibit KTN1/ADRM1 interaction at residues Met1-Ala252. These results are supported by studies in mouse xenografts and human patient samples. Collectively, our findings provide novel mechanistic insight into KTN1 regulation of EGFR degradation in cSCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Receptores ErbB/metabolismo , Proteínas de la Membrana/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Neoplasias Cutáneas/genética , Ubiquitina/metabolismo , Animales , Carcinoma de Células Escamosas/patología , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Desnudos , Neoplasias Cutáneas/patología , Transfección
11.
J Org Chem ; 86(20): 14004-14010, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33787277

RESUMEN

Application of a hypervalent fluoroiodane for the regiodivergent synthesis of dihydroxazines and fluorinated oxazepanes from allylaminoethanol was investigated. The reaction was carried out under mild conditions and gave the products in moderate to good yields. The selectivity of this transformation is controlled by the substituents of the allylaminoethanol.


Asunto(s)
Halogenación , Indicadores y Reactivos , Estructura Molecular
12.
ACS Biomater Sci Eng ; 7(2): 727-738, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33397089

RESUMEN

Obesity is a primary risk factor for type 2 diabetes, cardiovascular diseases, cancer, and other chronic diseases. Current antiobesity medications need frequent administration and show limited efficacy with severe side effects. Herein, browning agent rosiglitazone (Rsg) and antioxidant manganese tetroxide nanoparticles (MnNPs, around 250 nm) are integrated into electrospun short fibers (SF@Rsg-Mn) with a 1.5 µm width and a 20 µm length. Upon injection into inguinal adipose tissues, SF@Rsg-Mn are well retained in the local depots to sustainably release Rsg in 30 days for adipose tissue browning, while MnNPs on the fiber surface continuously scavenge adipose reactive oxygen species (ROS) for an extended period of time. Synergistic inhibition of fat accumulation through ROS scavenging and white adipocyte browning has been demonstrated for the first time, and the optimal synergistic ratio of Rsg and MnNPs is determined to be 1/14 via combination index examination. SF@Rsg-Mn inhibit lipid accumulation through downregulation of adipogenic gene PPARγ while promoting energy expenditure through upregulation of brown-specific gene UCP1 and mitochondrial function gene COX7A1. In a diet-induced obesity mouse model, a single injection of SF@Rsg-Mn into inguinal adipose tissues has accomplished a synergistic effect on body weight loss, fat reduction, glucose, and lipid metabolic improvement while minimizing adverse effects on other tissues, thereby paving the way to efficacious, safe, and practical treatment of obesity.


Asunto(s)
Adipogénesis , Diabetes Mellitus Tipo 2 , Tejido Adiposo Pardo , Animales , Antioxidantes , Dieta Alta en Grasa/efectos adversos , Ratones , Obesidad/tratamiento farmacológico
13.
Org Biomol Chem ; 18(48): 9873-9882, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33295925

RESUMEN

Herein we describe the PhI(OAc)2-mediated 1,1- and 1,2-difunctionalization of alkenes with N-tosyl amino alcohols to form oxazolidine and morpholine derivatives. This transformation was realized under mild reaction conditions and allows application to various substrates furnishing the multi-substituted oxazolidines and morpholines with yields up to 98%. A deuterium-labeling experiment was carried out and the result indicated that a phenyl group migration occurred to generate oxazolidine products.

14.
Org Biomol Chem ; 18(36): 6983-7001, 2020 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-32966541

RESUMEN

Olefins are a very important class of compounds and broadly used in the construction of various synthetic building blocks and practical industrial production. The difunctionalization of olefins provides one of the most powerful methods for the C-C or C-X bond formation with a rapid increase of the molecular complexity and synthetic value economically and effectively. Compared with the vigorous growth and abundant achievements of 1,2-difunctionalization of olefins, 1,1-difunctionalization is a relatively emerging and inadequately exploited research direction, despite being tremendously attractive from synthetic perspectives. In this minireview, we provide a brief overview of the advancements of 1,1-difunctionalization of olefins in the past twenty years, and prospects of future developments.

15.
Dose Response ; 18(2): 1559325820926735, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32528236

RESUMEN

INTRODUCTION: Acute exposure to ionizing radiation (IR) is hazardous or even lethal. Accurate estimation of the doses of IR exposure is critical to wisely determining the following treatments. Exosomes are nanoscale vesicles harboring biomolecules and mediate the communications among cells and tissues to influence biological processes. Screening out the microRNAs (miRNAs) contained in exosomes as biomarkers can be useful for estimating the IR exposure doses and exploring the correlation between these miRNAs and the occurrence of disease. METHODS: We treated mice with 2.0, 6.5, and 8.0 Gy doses of IR and collected the mice sera at 0, 24, 48, and 72 hours after exposure. Then, the serum exosomes were isolated by ultracentrifuge and the small RNA portion was extracted for sequencing and the following bioinformatics analysis. Qualitative polymerase chain reaction was performed to validate the potential dose-specific markers. RESULTS: Fifty-six miRNAs (31 upregulated, 25 downregulated) were differentially expressed after exposure of the above 3 IR doses and may act as common IR exposure miRNA markers. Bioinformatic analysis also identified several dosage-specific responsive miRNAs. Importantly, IR-induced miR-151-3p and miR-128-3p were significantly and stably increased at 24 hours in different mouse strains with distinct genetic background after exposed to 8.0 Gy of IR. CONCLUSION: Our study shows that miR-151-3p and miR-128-3p can be used as dose-specific biomarkers of 8.0 Gy IR exposure, which can be used to determine the exposure dose by detecting the amount of the 2 miRNAs in serum exosomes.

16.
Angew Chem Int Ed Engl ; 59(32): 13423-13429, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32367577

RESUMEN

Single-atom catalysts have demonstrated their superiority over other types of catalysts for various reactions. However, the reported nitrogen reduction reaction single-atom electrocatalysts for the nitrogen reduction reaction exclusively utilize metal-nitrogen or metal-carbon coordination configurations as catalytic active sites. Here, we report a Fe single-atom electrocatalyst supported on low-cost, nitrogen-free lignocellulose-derived carbon. The extended X-ray absorption fine structure spectra confirm that Fe atoms are anchored to the support via the Fe-(O-C2 )4 coordination configuration. Density functional theory calculations identify Fe-(O-C2 )4 as the active site for the nitrogen reduction reaction. An electrode consisting of the electrocatalyst loaded on carbon cloth can afford a NH3 yield rate and faradaic efficiency of 32.1 µg h-1 mgcat. -1 (5350 µg h-1 mgFe -1 ) and 29.3 %, respectively. An exceptional NH3 yield rate of 307.7 µg h-1 mgcat. -1 (51 283 µg h-1 mgFe -1 ) with a near record faradaic efficiency of 51.0 % can be achieved with the electrocatalyst immobilized on a glassy carbon electrode.

17.
Mol Med Rep ; 20(6): 4855-4866, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31638204

RESUMEN

Aberrant expression of the epidermal growth factor receptor (EGFR) plays vital roles in tumor development and progression. In the present study, ultraviolet irradiation induced the upregulation of EGFR in skin­derived keratinocytes, which may contribute to the development of cutaneous squamous cell carcinoma (CSCC). This was supported by the high expression of EGFR in CSCC clinical samples. Treating A431 CSCC cells with gefitinib, a tyrosine kinase inhibitor, activated the intrinsic mitochondrial apoptotic pathway while inducing protective autophagy. Combined application of chloroquine with gefitinib enhanced the treatment efficacy of gefitinib against CSCC by inhibiting autophagic flux. These findings demonstrated that autophagy inhibition may be an effective strategy for enhancing the sensitivity of EGFR­expressing cells to tyrosine kinase inhibitor treatment. Manipulating pro­survival autophagy by the combined application of chloroquine with gefitinib is a promising approach for improving the efficacy of EGFR inhibitors in cancer treatment. This may contribute to novel EGFR­targeted therapeutic strategies in the near future.


Asunto(s)
Antimaláricos/farmacología , Antineoplásicos/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Cloroquina/farmacología , Gefitinib/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Carcinoma de Células Escamosas/metabolismo , Línea Celular , Línea Celular Tumoral , Sinergismo Farmacológico , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Humanos , Inhibidores de Proteínas Quinasas/farmacología , Neoplasias Cutáneas/metabolismo
18.
Org Biomol Chem ; 17(40): 8977-8981, 2019 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-31576884

RESUMEN

A hypervalent iodane reagent used for the intramolecular cyclization of N-acetyl enamines and intermolecular cyclocondensation of enamines and nitriles was investigated. The reaction was performed under mild conditions and gave oxazoles and imidazoles, respectively, in moderate to excellent yields. This transformation exhibits good reactivity, selectivity and functional group tolerance. The selectivity of the intra- or intermolecular reaction is dependent on the structure of N-acetyl enamines.

19.
Oncol Lett ; 18(2): 1071-1080, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31423167

RESUMEN

The aim of the present study was to determine the ability of cone beam computed tomography (CBCT) to improve the accuracy of nasopharyngeal carcinoma (NPC) radiotherapy by analyzing the setup and inter-fraction errors at different levels and directions of the target volumes. A total of 113 patients with NPC who were undergoing intensity-modulated radiotherapy were recruited for the present study. Each patient had at least three CBCT exams prior to the start of radiation therapy. Three anatomic bony landmarks, including the upper neck, lower neck and head, were used to represent the different levels of assessment. The positioning errors were registered in three planes throughout the course of radiotherapy: The right-left (RL), superior-inferior (SI) and anterior-posterior (AP) directions. The planning CT images were matched with the CBCT images to determine the naso-pharynx shifts. A receiver operating characteristic curve was plotted to establish the specificity and sensitivity of CBCT. The planning target volume margin (MPTV) for the head was 0.9 mm, 1.4 mm for the upper neck and 2.0 mm for the lower neck. MPTVs of 1.5, 0.6 and 2.2 mm in the RL, SI and AP directions, respectively, were detected. In addition, there was evidence of setup errors in the three planes (RL, SI and AP) with the greatest error observed in the AP direction. Furthermore, the setup uncertainties in the neck region were greater than those of the head. In conclusion, CBCT could greatly improve the accuracy of radiotherapy by minimizing the setup errors and MPTV.

20.
Mar Pollut Bull ; 146: 865-873, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31426230

RESUMEN

To characterize the magnetic signature of sediment heavy metal contamination and identify sources of heavy metals in mangroves, 83 sediment specimens were collected from three mangroves in Fujian, China; various magnetic parameters and heavy metal concentrations were then determined. Variation in magnetic magnetization among specimens was linked to changes in pseudo-single-domain magnetite. Average values of Co, Cu, Ni, and Zn (but not Cr or Pb) were slightly lower than background levels. Geochemical evidence suggested that Co, Cr, Ni, Ti, and V were associated with lithogenic minerals in the sediment, while Cu, Pb, and Zn were associated with terrigenous minerals. A strong positive correlation was seen between magnetic concentration-dependent parameters and metal concentrations (Cu, Pb, and Zn), suggesting enrichment of metal-containing magnetic minerals with heavy metal pollution. The combined assessment of both sediment magnetic properties and heavy metal concentrations thus provides insight into the pollution status of mangrove sediments under complex conditions.


Asunto(s)
Sedimentos Geológicos/química , Metales Pesados/química , China , Monitoreo del Ambiente , Magnetismo , Contaminantes Químicos del Agua/química
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