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1.
J Org Chem ; 87(5): 2797-2808, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35076229

RESUMEN

A [3+1+1+1] annulation of arylamines, arylaldehydes, and dimethyl sulfoxide (DMSO) to the pyridine structure in quinolines using DMSO as a nonadjacent dual-methine (═CH-) synthon is disclosed. In this annulation, arylamines provide two carbon atoms and one nitrogen atom, arylaldehydes furnish one carbon atom, and DMSO provides two nonadjacent methines (═CH-) to the pyridine ring in quinoline molecules. This annulation provides a simple approach for the synthesis of 3-arylquinolines from readily available substrates in useful yields. On the basis of the control experiments and the literature, a plausible mechanism is proposed.


Asunto(s)
Dimetilsulfóxido , Quinolinas , Aminas , Carbono , Piridinas , Quinolinas/química
2.
J Org Chem ; 87(11): 7022-7032, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35583475

RESUMEN

The regioselective synthetic approach to higher alkenes from lower alkenes by using sulfoxides as alkyl or aryl reagents in the Fe3+/H2O2 system has been developed. This reaction realized direct alkylation or arylation of alkenes. In this reaction, sulfoxides afforded one Csp3 or Csp2 atom to the C═C bond of alkenes; one new Csp2-Csp3 bond or Csp2-Csp2 bond was formed. Nearly 40 products including di-, tri-, and tetra-substituted products were regioselectively synthesized. Both aliphatic and aromatic alkenes could participate in this reaction. Moreover, not only dimethyl sulfoxide but also three other sulfoxides can be applied to this reaction, including diethyl, dibenzyl, and diphenyl sulfoxide. The mechanism studies showed that this reaction may experience a coupling process via radical addition-elimination and the Fe3+/H2O2 system made the sulfoxides offered one alkyl or aryl radical to the C═C bond of alkenes.

3.
Clin Infect Dis ; 73(2): e513-e522, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32668459

RESUMEN

BACKGROUND: For pediatric pneumonia, the meteorological and air pollution indicators have been frequently investigated for their association with viral circulation but not for their impact on disease severity. METHODS: We performed a 10-year prospective, observational study in 1 hospital in Chongqing, China, to recruit children with pneumonia. Eight commonly seen respiratory viruses were tested. Autoregressive distributed lag (ADL) and random forest (RF) models were used to fit monthly detection rates of each virus at the population level and to predict the possibility of severe pneumonia at the individual level, respectively. RESULTS: Between 2009 and 2018, 6611 pediatric pneumonia patients were included, and 4846 (73.3%) tested positive for at least 1 respiratory virus. The patient median age was 9 months (interquartile range, 4‒20). ADL models demonstrated a decent fitting of detection rates of R2 > 0.7 for respiratory syncytial virus, human rhinovirus, parainfluenza virus, and human metapneumovirus. Based on the RF models, the area under the curve for host-related factors alone was 0.88 (95% confidence interval [CI], .87‒.89) and 0.86 (95% CI, .85‒.88) for meteorological and air pollution indicators alone and 0.62 (95% CI, .60‒.63) for viral infections alone. The final model indicated that 9 weather and air pollution indicators were important determinants of severe pneumonia, with a relative contribution of 62.53%, which is significantly higher than respiratory viral infections (7.36%). CONCLUSIONS: Meteorological and air pollution predictors contributed more to severe pneumonia in children than did respiratory viruses. These meteorological data could help predict times when children would be at increased risk for severe pneumonia and when interventions, such as reducing outdoor activities, may be warranted.


Asunto(s)
Contaminación del Aire , Neumonía , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Virosis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Niño , China/epidemiología , Humanos , Lactante , Neumonía/epidemiología , Neumonía/etiología , Estudios Prospectivos , Tiempo (Meteorología)
4.
Clin Infect Dis ; 73(11): e3851-e3858, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-33068430

RESUMEN

BACKGROUND: The growing epidemics of severe fever with thrombocytopenia syndrome (SFTS), an emerging tick-borne disease in East Asia, and its high case fatality rate have raised serious public health concerns. METHODS: Surveillance data on laboratory-confirmed SFTS cases in China were collected. The spatiotemporal dynamics and epidemiological features were explored. The socioeconomic and environmental drivers were identified for SFTS diffusion using survival analysis and for SFTS persistence using a two-stage generalized boosted regression tree model. RESULTS: During 2010‒2018, a total of 7721 laboratory-confirmed SFTS cases were reported in China, with an overall case fatality rate (CFR) of 10.5%. The average annual incidence increased >20 times and endemic areas expanded from 27 to 1574 townships, whereas the CFR declined from 19% to 10% during this period. Four geographical clusters-the Changbai Mountain area, the Jiaodong Peninsula, the Taishan Mountain area, and the Huaiyangshan Mountain area-were identified. Diffusion and persistence of the disease were both driven by elevation, high coverages of woods, crops, and shrubs, and the vicinity of habitats of migratory birds but had different meteorological drivers. Residents ≥60 years old in rural areas with crop fields and tea farms were at increased risk to SFTS. CONCLUSIONS: Surveillance of SFTS and intervention programs need to be targeted at areas ecologically suitability for vector ticks and in the vicinity of migratory birds to curb the growing epidemic.


Asunto(s)
Infecciones por Bunyaviridae , Phlebovirus , Síndrome de Trombocitopenia Febril Grave , Trombocitopenia , Infecciones por Bunyaviridae/epidemiología , China/epidemiología , Fiebre/epidemiología , Humanos , Persona de Mediana Edad
5.
Opt Express ; 29(23): 38451-38464, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34808898

RESUMEN

The single-shot capability of coherent modulation imaging (CMI) makes it have great potential in the investigation of dynamic processes. Its main disadvantage is the relatively low signal-to-noise ratio (SNR) which affects the spatial resolution and reconstruction accuracy. Here, we propose the improvement of a general spatiotemporal CMI method for imaging of dynamic processes. By making use of the redundant information in time-series reconstructions, the spatiotemporal CMI can achieve robust and fast reconstruction with higher SNR and spatial resolution. The method is validated by numerical simulations and optical experiments. We combine the CMI module with an optical microscope to achieve quantitative phase and amplitude reconstruction of dynamic biological processes. With the reconstructed complex field, we also demonstrate the 3D digital refocusing ability of the CMI microscope. With further development, we expect the spatiotemporal CMI method can be applied to study a range of dynamic phenomena.

6.
J Org Chem ; 86(21): 15228-15241, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34632772

RESUMEN

An unexpected annulation among 2-aminobenzyl alcohols, benzaldehydes, and DMSO to quinolines has been disclosed. For the reported annulation between 2-aminobenzyl alcohols and benzaldehydes, the change of the solvent from toluene to DMSO led to the change of the product from the diheteroatomic cyclic benzoxazines to monoheteroatomic cyclic quinolines. This annulation can be used to synthesize regioselectively different substituted quinolines by the choice of different 2-amino alcohols, aldehydes, and sulfoxides as substrates. Interestingly, introducing substituent groups to the α-position of sulfoxides resulted in the interchange of the positions between benzaldehydes and sulfoxides in the product quinolines. On the basis of the control experiments and literatures, a plausible mechanism for this annulation was proposed.


Asunto(s)
Benzaldehídos , Quinolinas , Aldehídos , Dimetilsulfóxido , Solventes
7.
J Org Chem ; 86(19): 13446-13453, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34546730

RESUMEN

Two C═C bond participation in annulation to pyridines using N,N-dimethylformamide (DMF) as the N1 and C4 synthons has been carried out. In this reaction, DMF contributed one N atom and one C atom to two disconnected positions of pyridine ring, with no need for an additional nitrogen source. Two C═C bonds in two molecules of substituted styrenes offered four carbon atoms in the presence of iodine and persulfate. With the optimized conditions in hand, both symmetric and unsymmetric diaryl-substituted pyridines were obtained in useful yields. On the basis of relevant literature and a series of control experimental results, a possible mechanism was proposed in this work, which may demonstrate how DMF provides both N1 and C4 sources.

8.
Bioorg Chem ; 105: 104401, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33113415

RESUMEN

Targeting the Trp-Kyn pathway is an attractive approach for cancer immunotherapy. Thioredoxin reductase (TrxR) enzymes are reactive oxygen species (ROS) modulators that are involved in the tumor cell growth and survival processes. The 4-phenylimidazole scaffold is well-established as useful for indoleamine 2,3-dioxygenase 1 (IDO1) inhibition, while piperlongumine (PL) and its derivatives have been reported to be inhibitors of TrxR. To take advantage of both immunotherapy and TrxR inhibition, we designed a first-generation dual IDO1 and TrxR inhibitor (ZC0101) using the structural combination of 4-phenylimidazole and PL scaffolds. ZC0101 exhibited better dual inhibition against IDO1 and TrxR in vitro and in cell enzyme assays than the uncombined forms of 4-phenylimidazole and PL. It also showed antiproliferative activity in various cancer cell lines, and a selective killing effect between normal and cancer cells. Furthermore, ZC0101 effectively induced apoptosis and ROS accumulation in cancer cells. Knockdown of TrxR1 and IDO1 expression induced cellular enzyme inhibition and ROS accumulation effects during ZC0101 treatment, but only reduced TrxR1 expression was able to improve ZC0101's antiproliferation effect. This proof-of-concept study provides a novel strategy for cancer treatment. ZC0101 represents a promising lead compound for the development of novel antitumor agents that can also be used as a valuable probe to clarify the relationships and mechanisms of cancer immunotherapy and ROS modulators.


Asunto(s)
Antineoplásicos/farmacología , Dioxolanos/farmacología , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Tiorredoxina Reductasa 1/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Dioxolanos/síntesis química , Dioxolanos/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Estructura Molecular , Especies Reactivas de Oxígeno/metabolismo , Relación Estructura-Actividad , Tiorredoxina Reductasa 1/metabolismo , Células Tumorales Cultivadas
9.
J Cell Physiol ; 234(7): 10386-10396, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30609034

RESUMEN

Long-noncoding RNAs (lncRNAs) is involved in the development of diverse diseases, including leukemia, while the role lncRNA HOX transcript antisense RNA (HOTAIR) played in leukemia remains unclear and in need of further investigation. Therefore, this study was conducted to explore the effects of lncRNA HOTAIR on the immunologic rejection of leukemia cells through the Wnt/ß-catenin in mice. Mice were administrated with HOTAIR mimics as well as small interfering RNA HOTAIR to explore the regulatory role of HOTAIR. The numbers of white blood cell (WBC) and platelet (PLT) and the content of hemoglobin in peripheral blood (PB) were determined. The cytokine level in PB was measured. T-lymphocyte proliferation activity, Ig production by B cells, natural killer (NK) cell activity, and the proportion of cluster of differentiation 4 (CD4)/CD8 T cell subsets were detected. Expression of HOTAIR, ß-catenin, cyclinD1, GSK-3ß, and c-Myc in bone marrow was determined. It was revealed that the WBC number increased, while the PLT number along with the hemoglobin content in PB decreased with the upregulated HOTAIR. Additionally, elevated HOTAIR led to decreased levels of transforming growth factor-ß, interferon-γ, interleukin-10, and tumor necrosis factor-α in PB, proliferation activity in T-lymphocyte, and inhibited Ig production, NK cell activity, and the ratio of CD4/CD8 T cell subsets in B-lymphocyte. Furthermore, Wnt/ß-catenin was activated by overexpressing HOTAIR. Enhanced survival and proliferation were shown with increased expression of cyclinD1, GSK-3ß, and c-Myc in the bone marrow of mice induced by overexpressing HOTAIR. These results indicate that restored HOTAIR reduces the immunologic rejection of leukemia cells in mice by activating Wnt/ß-catenin pathway.


Asunto(s)
Leucemia/genética , ARN Largo no Codificante/genética , Vía de Señalización Wnt/genética , beta Catenina/genética , Animales , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica/genética , Glucógeno Sintasa Quinasa 3 beta/genética , Ratones , Interferencia de ARN/fisiología , ARN Interferente Pequeño/genética , Transducción de Señal/genética , Regulación hacia Arriba/genética
10.
Bioorg Med Chem Lett ; 29(4): 549-555, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30630717

RESUMEN

With the aim of discovering novel cyclin-dependent kinase 8 (CDK8) inhibitors, a combined similarity search and molecular docking approach was employed, which led to 32 hits. Biological tests led to the discovery of several novel submicromolar inhibitors. In particular, compound C768-0769 (ZC0201) showed good CDK8 inhibitory activity, and compound ZC0201 effectively suppressed HCT-116 colorectal cancer cell proliferation by inducing G1/S transition arrest. Furthermore, modulation of phosphorylated signal transducer and activator of transcription 1 (Ser 727) (STAT1SER727), a pharmacodynamic biomarker of CDK8 activity, demonstrated that ZC0201 may cause G1/S transition arrest through CDK8 activity inhibition. Due to its good cellular activity, ZC0201 may be an ideal lead compound for further modification as a potential cancer therapeutic agent.


Asunto(s)
Quinasa 8 Dependiente de Ciclina/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores de Proteínas Quinasas/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/patología , Ensayos de Selección de Medicamentos Antitumorales , Fase G1/efectos de los fármacos , Células HCT116 , Humanos , Simulación del Acoplamiento Molecular , Fosforilación , Inhibidores de Proteínas Quinasas/química , Fase S/efectos de los fármacos , Factor de Transcripción STAT1/metabolismo
11.
Biochem Biophys Res Commun ; 506(4): 1004-1012, 2018 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-30404735

RESUMEN

BACKGROUND: Long non-coding RNAs (lncRNAs) can interact with microRNAs (miRNAs) as a competing endogenous RNA (ceRNA) to regulate the expression of target genes, which can largely influence on tumorigenesis and tumor progression. However, the role of lncRNA-mediated ceRNAs in cholangiocarcinoma (CCA) remains unknown. This study aimed to develop novel lncRNAs as well as their action mechanisms in CCA. METHODS: The expression profiles of lncRNAs, miRNAs, and mRNAs of 36 CCA tissues and 9 non-tumor bile duct tissues were obtained from The Cancer Genome Atlas (TCGA) database. The differentially expressed RNAs werre identified using the DESeq package in R. The ceRNA network was constructed in CCA based on bioinformatics generated from miRcode, miRTarBase, miRDB, and TargetScan. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using "DAVID 6.8" and R packages "Clusterprofile". Survival analysis was performed based on Kaplan-Meier curve analysis. RESULTS: We identified a total of 1411 differentially expressed lncRNAs, 3494 mRNAs, and 64 miRNAs between CCA and matched normal tissues. By combining the data predicted by databases with intersection RNAs, a lncRNA-miRNA-mRNA ceRNA network consisting of 116 lncRNAs, 14 miRNAs and 59 mRNAs was established. According to the survival analysis, we detected 11 DElncRNA to have a significant impact on the overall survival in patients with CCA (P < 0.05). CONCLUSIONS: Our study identified novel lncRNAs associated with CCA progression and prognosis and provided data to further understand lncRNA-mediated ceRNA regulatory mechanisms in the pathogenesis of CCA.


Asunto(s)
Colangiocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , ARN Largo no Codificante/genética , Perfilación de la Expresión Génica , Ontología de Genes , Humanos , Estimación de Kaplan-Meier , Mapas de Interacción de Proteínas/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
Mutagenesis ; 31(1): 35-41, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26188195

RESUMEN

The implications of disinfection by-products (DBPs) present in drinking water are of public health concern because of their potential mutagenic, carcinogenic and other toxic effects on humans. In this study, we selected 13 main DBPs found in drinking water to quantitatively analyse their cytotoxicity and genotoxicity using a microplate-based cytotoxicity assay and a developed SOS/umu assay in Salmonella typhimurium TA1535/pSK1002. With the developed SOS/umu test, eight DBPs: 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-fura3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H]-furanone (MX), dibromoacetonitrile (DBN), iodoacetic acid (IA), bromochloroacetonitrile (BCN), bromoacetic acid (BA), trichloroacetonitrile (TCN), dibromoacetic acid (DBA) and dichloroacetic acid (DCA) were significantly genotoxic to S. typhimurium. Three DBPs: chloroacetic acid (CA), trichloroacetic acid (TCA) and dichloroacetonitrile (DCN) were weakly genotoxic, whereas the remaining DBPs: chloroacetonitrile (CN) and chloral hydrate (CH) were negative. The rank order in decreasing genotoxicity was as follows: MX > DBN > IA > BCN > BA > TCN > DBA > DCA > CA, TCA, DCN > CN, CH. MX was approximately 370 000 times more genotoxic than DCA. In the microplate-based cytotoxicity assay, cytotoxic potencies of the 13 DBPs were compared and ranked in decreasing order as follows: MX > IA > DBN > BCN > BA > TCN > DCN > CA > DCA > DBA > CN > TCA > CH. MX was approximately 19 200 times more cytotoxic than CH. A statistically significant correlation was found between cytotoxicity and genotoxicity of the 13 DBPs in S. typhimurium. Results suggest that microplate-based cytotoxicity assay and the developed SOS/umu assay are feasible tools for analysing the cytotoxicity and genotoxicity of DBPs, particularly for comparing their toxic intensities quantitatively.


Asunto(s)
Desinfección , Agua Potable/química , Pruebas de Mutagenicidad , Mutágenos/toxicidad , Salmonella typhimurium/genética , Contaminantes Químicos del Agua/toxicidad , Acetatos/toxicidad , Acetonitrilos/toxicidad , Daño del ADN , Furanos/toxicidad , Salmonella typhimurium/efectos de los fármacos
13.
J Cardiovasc Pharmacol ; 67(5): 412-7, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26828321

RESUMEN

Epidemiological studies have suggested that hypercholesterolemia is an independent determinant of increased left ventricular (LV) mass. Because high-density lipoprotein and its major protein apolipoprotein A-I (apoA-I) mediate reverse cholesterol transport (RCT) and have cardiac protective effects, we hypothesized that the apoA-I mimetic peptide D-4F could promote RCT in cardiac tissue and decrease cardiac hypertrophy induced by hypercholesterolemia. Low-density lipoprotein receptor-null mice were fed by a Western diet for 18 weeks and then randomized to receive water, or D-4F 0.3 mg/mL, or D-4F 0.5 mg/mL added to drinking water for 6 weeks. After D-4F administration, an increase in high-density lipoprotein cholesterol and a decrease in low-density lipoprotein cholesterol, total cholesterol, and triglyceride in a trend toward dose-responsivity were found in cardiac tissue. Ultrasound biomicroscopy revealed a reduction in LV posterior wall end-diastolic dimension, and an increase in mitral valve E/A ratio and LV ejection fraction. Hematoxylin-eosin staining showed reduced LV wall thickness and myocardial cell diameter. The protein levels of ABCA1 and LXRα were elevated in cardiac tissue of D-4F treated mice compared with the controls (P < 0.05). These results demonstrated that D-4F treatment reduced cardiac hypertrophy, and improved cardiac performance in low-density lipoprotein receptor-null mice fed a Western diet, presumably through the LXRα-ABCA1 pathway associated with enhanced myocardial RCT.


Asunto(s)
Apolipoproteína A-I/farmacología , Cardiomegalia/fisiopatología , Colesterol/metabolismo , Transportador 1 de Casete de Unión a ATP/biosíntesis , Animales , Transporte Biológico , Cardiomegalia/etiología , LDL-Colesterol/metabolismo , Dieta Occidental , Femenino , Hipercolesterolemia/complicaciones , Receptores X del Hígado/biosíntesis , Ratones , Ratones Noqueados , Triglicéridos/metabolismo
14.
Comput Med Imaging Graph ; 113: 102344, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38320336

RESUMEN

Cone Beam Computed Tomography (CBCT) plays a crucial role in Image-Guided Radiation Therapy (IGRT), providing essential assurance of accuracy in radiation treatment by monitoring changes in anatomical structures during the treatment process. However, CBCT images often face interference from scatter noise and artifacts, posing a significant challenge when relying solely on CBCT for precise dose calculation and accurate tissue localization. There is an urgent need to enhance the quality of CBCT images, enabling a more practical application in IGRT. This study introduces EGDiff, a novel framework based on the diffusion model, designed to address the challenges posed by scatter noise and artifacts in CBCT images. In our approach, we employ a forward diffusion process by adding Gaussian noise to CT images, followed by a reverse denoising process using ResUNet with an attention mechanism to predict noise intensity, ultimately synthesizing CBCT-to-CT images. Additionally, we design an energy-guided function to retain domain-independent features and discard domain-specific features during the denoising process, enhancing the effectiveness of CBCT-CT generation. We conduct numerous experiments on the thorax dataset and pancreas dataset. The results demonstrate that EGDiff performs better on the thoracic tumor dataset with SSIM of 0.850, MAE of 26.87 HU, PSNR of 19.83 dB, and NCC of 0.874. EGDiff outperforms SoTA CBCT-to-CT synthesis methods on the pancreas dataset with SSIM of 0.754, MAE of 32.19 HU, PSNR of 19.35 dB, and NCC of 0.846. By improving the accuracy and reliability of CBCT images, EGDiff can enhance the precision of radiation therapy, minimize radiation exposure to healthy tissues, and ultimately contribute to more effective and personalized cancer treatment strategies.


Asunto(s)
Tomografía Computarizada de Haz Cónico Espiral , Reproducibilidad de los Resultados , Tórax , Fantasmas de Imagen
15.
J Immunother ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809517

RESUMEN

The infiltration of CD8+ T cells in the tumor microenvironment is associated with better survival and immunotherapy response. However, their roles in gastric cancer have not been explored so far. In here, the profiles of GC gene expression were collected from The Cancer Genome Atlas database. Single-cell transcriptomic data originated from GSE134520. Cell clustering, annotation, and CD8+ T-cell differential genes were from the TISCH database. We determined 896 CD8+ T-cell differential genes by scRNA-seq analysis. After integrating immune-related genes, 174 overlapping genes were obtained and a novel risk model was subsequently built. The performance of CD8+ T-cell-associated gene signature was assessed in the training and external validation sets. The gene signature showed independent risk factors of overall survival for GC. A quantitative nomogram was built to enhance the clinical efficacy of this signature. Furthermore, low-risk individuals showed higher mutation status, higher immune checkpoint expression, low Tumour Immune Dysfunction and Exclusion (TIDE) scores, and higher IPS-PD-1 combined IPS-CTLA4 scores, indicating a greater response to immunotherapy. In addition, analysis of IMvigor210 immunotherapy cohort demonstrated that low-risk individuals had a favorable response to prognosis and immunotherapy. In conclusion, we generated a CD8+ T-cell-related signature that can serve as a promising tool for personalized prognosis prediction and guiding decisions regarding immunotherapy in GC patients.

16.
J Cancer ; 15(11): 3350-3361, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38817855

RESUMEN

This study has used machine learning algorithms to develop a predictive model for differentiating between dermoscopic images of basal cell carcinoma (BCC) and actinic keratosis (AK). We compiled a total of 904 dermoscopic images from two sources - the public dataset (HAM10000) and our proprietary dataset from the First Affiliated Hospital of Dalian Medical University (DAYISET 1) - and subsequently categorised these images into four distinct cohorts. The study developed a deep learning model for quantitative analysis of image features and integrated 15 machine learning algorithms, generating 207 algorithmic combinations through random combinations and cross-validation. The final predictive model, formed by integrating XGBoost with Lasso regression, exhibited effective performance in the differential diagnosis of BCC and AK. The model demonstrated high sensitivity in the training set and maintained stable performance in three validation sets. The area under the curve (AUC) value reached 1.000 in the training set and an average of 0.695 in the validation sets. The study concludes that the constructed discriminative diagnostic model based on machine learning algorithms has excellent predictive capabilities that could enhance clinical decision-making efficiency, reduce unnecessary biopsies, and provide valuable guidance for further treatment.

17.
Front Oncol ; 14: 1294440, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38406803

RESUMEN

Background: This study aimed to establish and validate a prognostic model based on immune-related genes (IRGPM) for predicting disease-free survival (DFS) in patients with locally advanced rectal cancer (LARC) undergoing neoadjuvant chemoradiotherapy, and to elucidate the immune profiles associated with different prognostic outcomes. Methods: Transcriptomic and clinical data were sourced from the Gene Expression Omnibus (GEO) database and the West China Hospital database. We focused on genes from the RNA immune-oncology panel. The elastic net approach was employed to pinpoint immune-related genes significantly impacting DFS. We developed the IRGPM for rectal cancer using the random forest technique. Based on the IRGPM, we calculated prognostic risk scores to categorize patients into high-risk and low-risk groups. Comparative analysis of immune characteristics between these groups was conducted. Results: In this study, 407 LARC samples were analyzed. The elastic net identified a signature of 20 immune-related genes, forming the basis of the IRGPM. Kaplan-Meier survival analysis revealed a lower 5-year DFS in the high-risk group compared to the low-risk group. The receiver operating characteristic (ROC) curve affirmed the model's robust predictive capability. Validation of the model was performed in the GSE190826 cohort and our institution's cohort. Gene expression differences between high-risk and low-risk groups predominantly related to cytokine-cytokine receptor interactions. Notably, the low-risk group exhibited higher immune scores. Further analysis indicated a greater presence of activated B cells, activated CD8 T cells, central memory CD8 T cells, macrophages, T follicular helper cells, and type 2 helper cells in the low-risk group. Additionally, immune checkpoint analysis revealed elevated PDCD1 expression in the low-risk group. Conclusions: The IRGPM, developed through random forest and elastic net methodologies, demonstrates potential in distinguishing DFS among LARC patients receiving standard treatment. Notably, the low-risk group, as defined by the IRGPM, showed enhanced activation of adaptive immune responses within the tumor microenvironment.

18.
Artículo en Inglés | MEDLINE | ID: mdl-37910404

RESUMEN

Radical prostatectomy (prostate removal) is a standard treatment for clinically localized prostate cancer and is often followed by postoperative radiotherapy. Postoperative radiotherapy requires accurate delineation of the clinical target volume (CTV) and lymph node drainage area (LNA) on computed tomography (CT) images. However, the CTV contour cannot be determined by the simple prostate expansion after resection of the prostate in the CT image. Constrained by this factor, the manual delineation process in postoperative radiotherapy is more time-consuming and challenging than in radical radiotherapy. In addition, CTV and LNA have no boundaries that can be distinguished by pixel values in CT images, and existing automatic segmentation models cannot get satisfactory results. Radiation oncologists generally determine CTV and LNA profiles according to clinical consensus and guidelines regarding surrounding organs at risk (OARs). In this work, we design a cascade segmentation block to explicitly establish correlations between CTV, LNA, and OARs, leveraging OARs features to guide CTV and LNA segmentation. Furthermore, inspired by the success of the self-attention mechanism and self-supervised learning, we adopt SwinTransformer as our backbone and propose a pure SwinTransformer-based segmentation network with self-supervised learning strategies. We performed extensive quantitative and qualitative evaluations of the proposed method. Compared to other competitive segmentation models, our model shows higher dice scores with minor standard deviations, and the detailed visualization results are more consistent with the ground truth. We believe this work can provide a feasible solution to this problem, making the postoperative radiotherapy process more efficient.

19.
Phytochemistry ; 205: 113485, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36334789

RESUMEN

Nicotiana tabacum (tobacco) has attracted interest as one of the most economically important industrial crops widely cultivated in China, whose dried leaves are popularly consumed medicinally and recreationally by human societies. In this study, five undescribed alkaloids derivatives, isoaspergillines A-E, together with eight known alkaloids, notoamide D, (1R,4S)-4-benzyl-1-isopropyl-2,4-dihydro-1H-pyrazino-[2,1-b]quinazoline-3,6-dione, protuboxepin K, notoamide C, notoamide M, deoxybrevianamide E, cyclo (D-Pro-L-Trp), and versicolamide B, were obtained from the culture of the Nicotiana tabacum-derived fungus Aspergillus versicolor. Their structures were mainly elucidated through comprehensive analyses of spectroscopic data. Bioactivity evaluation of all isolated compounds revealed that isoaspergilline A and notoamide M exhibited anti-TMV activities with IC50 values of 20.0 and 22.8 µM, respectively. Molecular docking suggested that isoaspergilline A and notoamide M were well located into the active site of anti-TMV by interacting with SER138, SER143, and ASN73 residues. This study enlightens the therapeutic potential of the endophytic fungus A. versicolor and it is helpful to find undescribed anti-TMV activity inhibitors, as well as searching for new anti-TMV candidates from natural sources.


Asunto(s)
Nicotiana , Humanos , Simulación del Acoplamiento Molecular , China
20.
Org Lett ; 25(13): 2306-2311, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-36988237

RESUMEN

A novel and efficient method for the catalytic installation of a carbonyl group via remote radical coupling is disclosed. The nickel-catalyzed reaction proceeds to undergo a sequential single-electron transfer, 1,5-hydrogen atom transfer, and carbonyl insertion, thus providing the α-substituted ketone. Further, this reaction could be carried out smoothly under normal pressure and redox-neutral conditions, and demonstrated functional-group compatibility and excellent site-selectivity.

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