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1.
Eur Radiol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637428

RESUMO

OBJECTIVE: To investigate the associations between apparent diffusion coefficient (ADC) values extracted from three different region of interest (ROI) position approaches and programmed cell death ligand-1 (PD-L1) expression, and evaluate the performance of the nomogram established based on ADC values and clinicopathological parameters in predicting PD-L1 expression in cervical cancer (CC) patients. METHODS: Through retrospective recruitment, a training cohort of 683 CC patients was created, and a validation cohort of 332 CC patients was prospectively recruited. ROIs were delineated using three different methods to measure the mean ADC (ADCmean), single-section ADC (ADCss), and the minimum ADC of tumors (ADCmin). Logistic regression was employed to identify independent factors related to PD-L1 expression. A nomogram was drawn based on ADC values combined with clinicopathological features, its discrimination and calibration performances were estimated using the area under the curve (AUC) of receiver operating characteristic and calibration curve. The clinical benefits were evaluated by decision curve analysis. RESULTS: The ADCmin independently correlated with PD-L1 expression. The nomogram constructed with ADCmin and other independent clinicopathological-related factors: FIGO staging, pathological grade, parametrial invasion, and lymph node status demonstrated excellent diagnostic performance (AUC = 0.912 and 0.903, respectively), good calibration capacities, and greater net benefits compared to the clinicopathological model in both the training and validation cohorts. CONCLUSION: ADCmin independently correlated PD-L1 expression, and the nomogram established with ADCmin and clinicopathological independent prognostic factors had a strong predictive performance for PD-L1 expression, thereby serving as a promising tool for selecting cases eligible for immunotherapy. CLINICAL RELEVANCE STATEMENT: The minimum ADC can serve as a reliable imaging biomarker related to PD-L1 expression; the established nomogram combines the minimum ADC and clinicopathological factors that can assist clinical immunotherapy decisions.

2.
Environ Sci Pollut Res Int ; 31(21): 31646-31655, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38668945

RESUMO

The diversity of microalgae and bacteria allows them to form beneficial consortia for efficient wastewater treatment and nutrient recovery. This study aimed to evaluate the feasibility of a new microalgal-bacterial combination in the treatment of ice cream wastewater for biomass harvest. The bacterium Novosphingobium sp. ICW1 was natively isolated from ice cream wastewater and the microalga Vischeria sp. WL1 was a terrestrial oil-producing strain of Eustigmatophyceae. The ice cream wastewater was diluted 4 folds for co-cultivation, which was relatively less inhibitory for the growth of Vischeria sp. WL1. Four initial algal-bacterial combinations (v:v) of 150:0 (single algal cultivation), 150:1, 150:2, and 150:4 were assessed. During 24 days of co-cultivation, algal pigmentation was dynamically changed, particularly at the algal-bacterial combination of 150:4. Algal growth (in terms of cell number) was slightly promoted during the late phase of co-cultivation at the combinations of 150:2 and 150:4, while in the former the cellular oil yield was obviously elevated. Treated by these algal-bacterial combinations, total carbon was reduced by 67.5 ~ 74.5% and chemical oxygen demand was reduced by 55.0 ~ 60.4%. Although single bacterial treatment was still effective for removing organic nutrients, the removal efficiency was obviously enhanced at the algal-bacterial combination of 150:4. In addition, the harvested oils contained 87.1 ~ 88.3% monounsaturated fatty acids. In general, this study enriches the biotechnological solutions for the sustainable treatment of organic matter-rich food wastewater.


Assuntos
Biomassa , Microalgas , Águas Residuárias , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Bactérias/metabolismo
3.
Radiol Med ; 129(5): 751-766, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38512623

RESUMO

PURPOSE: To compare machine learning (ML) models with logistic regression model in order to identify the optimal factors associated with mammography-occult (i.e. false-negative mammographic findings) magnetic resonance imaging (MRI)-detected newly diagnosed breast cancer (BC). MATERIAL AND METHODS: The present single-centre retrospective study included consecutive women with BC who underwent mammography and MRI (no more than 45 days apart) for breast cancer between January 2018 and May 2023. Various ML algorithms and binary logistic regression analysis were utilized to extract features linked to mammography-occult BC. These features were subsequently employed to create different models. The predictive value of these models was assessed using receiver operating characteristic curve analysis. RESULTS: This study included 1957 malignant lesions from 1914 patients, with an average age of 51.64 ± 9.92 years and a range of 20-86 years. Among these lesions, there were 485 mammography-occult BCs. The optimal features of mammography-occult BC included calcification status, tumour size, mammographic density, age, lesion enhancement type on MRI, and histological type. Among the different ML models (ANN, L1-LR, RF, and SVM) and the LR-based combined model, the ANN model with RF features was found to be the optimal model. It demonstrated the best discriminative performance in predicting mammography false- negative findings, with an AUC of 0.912, an accuracy of 86.90%, a sensitivity of 85.85%, and a specificity of 84.18%. CONCLUSION: Mammography-occult MRI-detected breast cancers have features that should be considered when performing breast MRI to improve the detection rate for breast cancer and aid in clinician management.


Assuntos
Neoplasias da Mama , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Mamografia , Humanos , Neoplasias da Mama/diagnóstico por imagem , Feminino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Estudos Retrospectivos , Adulto , Idoso , Modelos Logísticos , Idoso de 80 Anos ou mais , Adulto Jovem , Reações Falso-Negativas , Curva ROC
4.
Biotechnol Rep (Amst) ; 41: e00823, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38179180

RESUMO

Salt lakes are significant components of global inland waters. Salt lake (SL) water can provide precious mineral resource for microbial growth. The prospect of utilizing diluted SL water for cultivation of a terrestrial oil-producing microalga Vischeria sp. WL1 was evaluated under laboratory conditions. Based on the detected mineral element composition, the water from Gouchi Salt Lake was diluted 2, 4, 6 and 8 folds and used with supplementation of additional nitrogen, phosphorus and iron (SL+ water). It was found that 4 folds diluted SL+ water was most favorable for biomass and oil production. When cultivated in this condition, Vischeria sp. WL1 gained a biomass yield of 0.82 g L-1 and an oil yield of 0.56 g L-1 after 24 days of cultivation, which is comparable to the optimum productivity we previously established. In addition, total monounsaturated fatty acid contents (64.4∼68.1 %) of the oils resulted from cultures in diluted SL+waters were higher than that in the control (55.5 %). It was also noteworthy that in all these cultures the oil contents (652.0∼681.0 mg g-1) accounted for the most of the biomass, which are far more than the protein and starch contents. This study demonstrates the feasibility of using SL water as a cost-effective mineral resource to cultivate microalgae for biomass and oil production.

5.
Yi Chuan ; 45(1): 52-66, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36927638

RESUMO

As an effective supplement to the current forensic DNA typing and one of the research hotpots in forensic science, the in-depth mining and characterization of biological evidence can provide rich and reliable clues for case investigation. In this study, the time-dependent variations of transcriptome were confirmed in in vitro blood samples within 0-168 days and a random forest model was established to realize the classification of blood samples with different TSD (time since deposition). Meanwhile, significant differences were observed in the transcripts of blood samples with different smoking habits and genders within a certain time period. HLA-DRB1, HLA-DQB1 and HLA-DQA2 were identified as markers for smoking habit identification, while the transcripts for RPS4Y1 and EIF1AY from the non-recombining region of the Y chromosome (NRY) were identified as markers for male sex identification. Thus, this study provides a theoretical foundation and experimental strategy for establishing a transcriptome-based method for characterizing blood sample retention time and donor characteristics in the field of forensic investigation.


Assuntos
Transcriptoma , Humanos , Masculino , Feminino , Cadeias HLA-DRB1/genética , Reação em Cadeia da Polimerase , Alelos
6.
Nat Nanotechnol ; 17(12): 1258-1264, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36302961

RESUMO

Multilayer van der Waals (vdW) film materials have attracted extensive interest from the perspective of both fundamental research1-3 and technology4-7. However, the synthesis of large, thick, single-crystal vdW materials remains a great challenge because the lack of out-of-plane chemical bonds weakens the epitaxial relationship between neighbouring layers8-31. Here we report the continuous epitaxial growth of single-crystal graphite films with thickness up to 100,000 layers on high-index, single-crystal nickel (Ni) foils. Our epitaxial graphite films demonstrate high single crystallinity, including an ultra-flat surface, centimetre-size single-crystal domains and a perfect AB-stacking structure. The exfoliated graphene shows excellent physical properties, such as a high thermal conductivity of ~2,880 W m-1 K-1, intrinsic Young's modulus of ~1.0 TPa and low doping density of ~2.2 × 1010 cm-2. The growth of each single-crystal graphene layer is realized by step edge-guided epitaxy on a high-index Ni surface, and continuous growth is enabled by the isothermal dissolution-diffusion-precipitation of carbon atoms driven by a chemical potential gradient between the two Ni surfaces. The isothermal growth enables the layers to grow at optimal conditions, without stacking disorders or stress gradients in the final graphite. Our findings provide a facile and scalable avenue for the synthesis of high-quality, thick vdW films for various applications.

7.
Biochem Pharmacol ; 200: 115037, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35427571

RESUMO

Accumulating evidence has supported that targeting oxidative stress and metabolic alterations of cancer is an effective strategy to combat cancer. We previously reported that Dimethylaminomicheliolide (DMAMCL) and its active metabolite micheliolide (MCL) can cause oxidative stress and cell death in leukemia and glioblastoma. However, the detailed mechanism underlying MCL or DMAMCL triggered oxidative stress remains elusive. Herein, using leukemia HL60 cells and glioblastoma U118MG cells as models, we found that MCL-induced oxidative stress is mainly mediated by reduced glutathione (GSH). Overproduced reactive oxygen species (ROS) can lead to oxidative damage to mitochondrial, impairing the ability of the tricarboxylic acid (TCA) cycle and causing dysfunction of mitochondrial respiratory chain. On the other hand, the depletion of GSH activates GSH biosynthesis pathway and has possibility to give rise to more GSH to scavenge ROS in cancer cells. Targeting this redox and metabolic circuit, we identified L-buthionine sulfoximine (BSO), an inhibitor in GSH biosynthesis, as an agent that can enhance MCL regimen to inhibit GSH compensatory event and thereby further facilitate cancer cell oxidative stress. Together, these results illustrate that targeting redox and metabolic pathway by MCL/DMAMCL combination with BSO is a potent therapeutic intervention for the treatments of glioblastoma and acute-myelocytic leukemia.


Assuntos
Glioblastoma , Leucemia , Apoptose , Butionina Sulfoximina/farmacologia , Glioblastoma/tratamento farmacológico , Glutationa/metabolismo , Humanos , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos de Guaiano
8.
Adv Mater ; 34(2): e2105276, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34738668

RESUMO

Electrochemical sensors for detecting micromolecule organics are desirable for improving the perception of environmental quality and human health. However, currently, the electrochemical sensors for formaldehyde are substantially limited on the market due to the long-term unsolved problems of the low electrooxidation efficiency and CO poisoning issue of commercial Pd catalysts. Here, a 2D Cr-doped Pd metallene (Cr-Pdene) with few atomic layers is shown as an advanced catalyst for ultrasensitive and selective sensing of formaldehyde via a highly efficient formaldehyde electrooxidation. It is found that the doping of Cr into Pd metallene can efficiently optimize the electronic structure of Pd and weaken the interaction between Pd and CO, providing an anti-poisoning means to favor CO2 production and suppress CO adsorption. The Cr-Pdene-based electrochemical sensor exhibits one order of magnitude higher detection range and, especially, much higher anti-interference for formaldehyde than that of the conventional sensors. Most importantly, it is demonstrated that the Cr-Pdene can be integrated into commercializable wireless sensor networks or handheld instruments for promising applications relating to the environment, health, and food.

9.
Front Oncol ; 9: 993, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632919

RESUMO

Glioblastoma (GBM) is the most prevalent malignant tumor in the central nervous system. Aerobic glycolysis, featured with elevated glucose consumption and lactate production, confers selective advantages on GBM by utilizing nutrients to support rapid cell proliferation and tumor growth. Pyruvate kinase 2 (PKM2), the last rate-limiting enzyme of glycolysis, is known to regulate aerobic glycolysis, and considered as a novel cancer therapeutic target. Herein, we aim to describe the cellular functions and mechanisms of a small molecular compound dimethylaminomicheliolide (DMAMCL), which has been used in clinical trials for recurrent GBM in Australia. Our results demonstrate that DMAMCL is effective on the inhibition of GBM cell proliferation and colony formation. MCL, the active metabolic form of DMAMCL, selectively binding to monomeric PKM2 and promoting its tetramerization, was also found to improve the pyruvate kinase activity of PKM2 in GBM cells. In addition, non-targeting metabolomics analysis reveals multiple metabolites involved in glycolysis, including lactate and glucose-6-phosphate, are decreased with DMAMCL treatment. The inhibitory effects of DMAMCL are observed to decrease in GBM cells upon PKM2 depletion, further confirming the importance of PKM2 in DMAMCL sensitivity. In conclusion, the activation of PKM2 by DMAMCL results in the rewiring aerobic glycolysis, which consequently suppresses the proliferation of GBM cells. Hence, DMAMCL represents a potential PKM2-targeted therapeutic agent against GBM.

10.
Bioorg Med Chem Lett ; 29(6): 802-805, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30713024

RESUMO

O-Linked N-acetylglucosamine (O-GlcNAc) is an abundant posttranslationalmonosaccaride-modification found on Ser or Thr residues of intracellular proteins in most eukaryotes. The dynamic nature of O-GlcNAc has enabled researchers to modulate the stoichiometry of O-GlcNAc on proteins in order to investigate its function. Cell permeable small moleculars have proven invaluable tools to increase O-GlcNAc levels. Herein, using in vitro substrate screening, we identified GlcNAcF3 as an OGT-accepted but OGA-resistant sugar mimic. Cellular experiments with cell-permeable peracetylated-GlcNAcF3 (Ac4GlcNAcF3) displayed that Ac4GlcNAcF3 was a potent tool to increase O-GlcNAc levels in several cell lines. Further, NIH3T3 cells interfered with OGT (siOGT) showed significant decreasing of O-GlcNAc levels with Ac4GlcNAcF3 treatment, indicating O-GlcNAcF3 was an OGT-dependent modification. In addition, cellular toxic assay confirmed O-GlcNAcF3 production has no significant effect on cell proliferation or viability. Thus, Ac4GlcNAcF3 represents a safe and dual regulator for both OGT and OGA, which will benefit the study of O-GlcNAc.


Assuntos
Acetilglucosamina/análogos & derivados , Acetilglucosamina/farmacologia , Inibidores Enzimáticos/farmacologia , N-Acetilglucosaminiltransferases/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo , Acetilglucosamina/toxicidade , Animais , Linhagem Celular Tumoral , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/toxicidade , Glicosilação/efeitos dos fármacos , Humanos , Camundongos , Células NIH 3T3 , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores
11.
J Electron Microsc (Tokyo) ; 59(4): 285-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20181725

RESUMO

The higher-order harmonic resonances, including second and third harmonic modes, were induced by applying alternative current signals inside a high-resolution transmission electron microscope (HRTEM), which have been used to study the mechanical properties of individual cadmium sulphide (CdS) nanowires. Young's moduli (E) and mechanical quality factors (Q) of individual CdS nanowires with diameters in the range of 50-350 nm were measured with the assistance of the mechanical resonances. The results indicate that the smooth nanowires have larger E and Q in comparison with the rough nanowires, and for the rough nanowires, E and Q increase with increasing diameters. The morphology- and size-dependent mechanical properties of CdS nanowires are directly correlated with their structure, as imaged by in situ TEM.

12.
Fa Yi Xue Za Zhi ; 25(1): 42-3, 2009 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-19397214

RESUMO

OBJECTIVE: To improve DNA extraction from human epithelium. METHODS: Chelex-100, Chelex-100 organic combined and Chelex-100 magnetism pearl combined methods were adopted according to the situation of each case. RESULTS: With the stepwise extracting protocol, the trace amount of DNA was analyzed most efficiently and the success rate of DNA extracting was better improved. CONCLUSION: The efficiency of DNA extraction from human epithelium could be greatly improved by modifying the extracting protocol such as purification and concentration based on previous results.


Assuntos
DNA/isolamento & purificação , Células Epiteliais/citologia , Genética Forense , Reação em Cadeia da Polimerase/métodos , DNA/análise , Humanos , Resinas Sintéticas/química
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