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1.
Angew Chem Int Ed Engl ; : e202412759, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39078800

RESUMEN

Low dimensional (LD) organic metal halide hybrids (OMHHs) have recently emerged as new generation functional materials with exceptional structural and property tunability. Despite the remarkable advances in the development of LD OMHHs, optical properties have been the major functionality extensively investigated for most of LD OMHHs developed to date, while other properties, such as magnetic and electronic properties, remain significantly under-explored. Here we report for the first time the characterization of the magnetic and electronic properties of a 1D OMHH, organic-copper (II) chloride hybrid (C8H22N2)Cu2Cl6. Owing to the antiferromagnetic coupling between Cu atoms through chloride bridges in 1D [Cu2Cl62-]∞ chains, (C8H22N2)Cu2Cl6 is found to exhibit antiferromagnetic ordering with a Néel temperature of 24K. The two-terminal (2T) electrical measurement on a (C8H22N2)Cu2Cl6 single crystal reveals its insulating nature. This work shows the potential of LD OMHHs as a highly tunable quantum material platform for spintronics.

2.
FASEB J ; 36(3): e22229, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35199870

RESUMEN

The radioresistance induced by hypoxia is the major obstacle in the successful treatment of cancer radiotherapy. p21 was initially identified as a widespread inhibitor of cyclin-dependent kinases, through which mediates the p53-dependent cell cycle G1 phase arrest in response to a variety of stress stimuli. In this study, we discovered a novel function of p21, which participated in the regulation of metabolic pathways under hypoxia. We found that p21 was upregulated in glioblastoma (GBM) cells under hypoxic conditions, which enhanced the radioresistance of GBM cells. In principle, HIF-1α is bound directly to the hypoxia response elements (HREs) of the p21 promoter to enhance its transcription activity, in turn, p21 also promoted the transcription of HIF-1α at the mRNA level and maintained HIF-1α function under oxygen deficiency. The positive correlation between p21 and HIF-1α augmented Glut1/LDHA-mediated glycolysis and aggravated the radioresistance of GBM cells. Thus, our results constructed a positive feedback circuit comprising p21/HIF-1α that might play a key role in enhancing the radioresistance of GBM under hypoxia.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Glioblastoma/metabolismo , Glucólisis , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hipoxia Tumoral , Animales , Neoplasias Encefálicas/radioterapia , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Retroalimentación Fisiológica , Femenino , Glioblastoma/radioterapia , Transportador de Glucosa de Tipo 1/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , L-Lactato Deshidrogenasa/metabolismo , Ratones , Tolerancia a Radiación
3.
Bioorg Med Chem ; 26(3): 747-757, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29317150

RESUMEN

Both histone deacetylase (HDAC) and fibroblast growth factor receptor (FGFR) are important targets for cancer therapy. Although combining dual HDAC pharmacophore with tyrosine kinase inhibitors (TKIs) had achieved a successful progress, dual HDAC/FGFR1 inhibitors haven't been reported yet. Herein, we designed a series of hybrids bearing 1H-indazol-3-amine and benzohydroxamic acids scaffold with scaffold hopping and molecular hybridization strategies. Among them, compound 7j showed the most potent inhibitory activity against HDAC6 with IC50 of 34 nM and exhibited the great inhibitory activities against a human breast cancer cell line MCF-7 with IC50 of 9 µM in vitro. Meanwhile, the compound also exhibited moderate FGFR1 inhibitory activities. This study provides new tool compounds for further exploration of dual HDAC/FGFR1 inhibition.


Asunto(s)
Diseño de Fármacos , Histona Desacetilasa 6/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/síntesis química , Indazoles/química , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Sitios de Unión , Supervivencia Celular/efectos de los fármacos , Histona Desacetilasa 6/metabolismo , Inhibidores de Histona Desacetilasas/toxicidad , Humanos , Indazoles/toxicidad , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Células MCF-7 , Simulación del Acoplamiento Molecular , Estructura Terciaria de Proteína , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Relación Estructura-Actividad
4.
J Orthop Sci ; 23(5): 793-800, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29910098

RESUMEN

BACKGROUND: The objective of this study was to assess whether intravenous acetaminophen for patients undergoing knee or hip arthroplasty could reduce the opioid consumption and improve pain management. METHOD: Eligible studies were searched from electronic databases including PubMed, Web of Science, Embase (Ovid interface) and Cochrane Library (Ovid interface). The quality assessments were performed according to the Cochrane systematic review method. The assessed outcomes were including opioid consumption, pain scores, length of hospital stays and total occurrence of adverse events. RESULTS: Among 832 records identified, six randomized controlled trials (RCTs) and five non-RCTs were eligible for data extraction and meta-analysis. According to the outcomes, the patients receive intravenous acetaminophen had less total opioid consumption after knee or hip artroplasty (SMD = -0.66; 95%CI, -1.13 to -0.20), but they did not obtain statistical improvement of postoperative pain control at postoperative day 0 (POD0, SMD = -0,15; 95%CI, -0.36 to 0.07), POD1(SMD = 0,12; 95%CI, -0.13 to 0.36), POD2 (SMD = -0,29; 95%CI, -0.70 to 0.12) and POD3 (SMD = -0,04; 95%CI, -0.49 to 0.41). Meanwhile, there were similar outcomes about the length of hospital stays in patients whether or not receiving intravenous acetaminophen (SMD = -0,05; 95%CI, -0.26 to 0.15). And, the total adverse effects occurrence also didn't show any significant difference between the acetaminophen group and control group (OR = 0.87; 95%CI, 0.57 to 1.33). CONCLUSIONS: Perioperative intravenous acetaminophen use in multimodal analgesia could significantly reduce of total opioid consumption, but it did not contribute to decrease the average pain scores and shorten the length of hospital stays in total hip or knee arthroplasty.


Asunto(s)
Acetaminofén/uso terapéutico , Analgésicos no Narcóticos/uso terapéutico , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Dolor Postoperatorio/tratamiento farmacológico , Analgésicos Opioides/uso terapéutico , Humanos , Infusiones Intravenosas , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología
5.
Molecules ; 23(9)2018 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-30142916

RESUMEN

The purpose of this research was to evaluate whether maltol could protect from hepatic injury induced by carbon tetrachloride (CCl4) in vivo by inhibition of apoptosis and inflammatory responses. In this work, maltol was administered at a level of 100 mg/kg for 15 days prior to exposure to a single injection of CCl4 (0.25%, i.p.). The results clearly indicated that the intrapulmonary injection of CCl4 resulted in a sharp increase in serum aspartate transaminase (AST) and alanine transaminase (ALT) activities, tumor necrosis factor-α (TNF-α), irreducible nitric oxide synthase (iNOS), nuclear factor-kappa B (NF-κB) and interleukin-1ß (IL-1ß) levels. Histopathological examination demonstrated severe hepatocyte necrosis and the destruction of architecture in liver lesions. Immunohistochemical staining and western blot analysis suggested an accumulation of iNOS, NF-κB, IL-1ß and TNF-α expression. Maltol, when administered to mice for 15 days, can significantly improve these deleterious changes. In addition, TUNEL and Hoechst 33258 staining showed that a liver cell nucleus of a model group diffused uniform fluorescence following CCl4 injection. Maltol pretreatment groups did not show significant cell nuclear condensation and fragmentation, indicating that maltol inhibited CCl4-induced cell apoptosis. By evaluating the liver catalase (CAT), glutathione (GSH), superoxide dismutase (SOD) activity, and further using a single agent to evaluate the oxidative stress in CCl4-induced hepatotoxicity by immunofluorescence staining, maltol dramatically attenuated the reduction levels of hepatic CAT, GSH and SOD, and the over-expression levels of CYP2E1 and HO-1. In the mouse model of CCl4-induced liver injury, we have demonstrated that the inflammatory responses were inhibited, the serum levels of ALT and AST were reduced, cell apoptosis was suppressed, and liver injury caused by CCl4 was alleviated by maltol, demonstrating that maltol may be an efficient hepatoprotective agent.


Asunto(s)
Tetracloruro de Carbono/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Hígado/efectos de los fármacos , Hígado/lesiones , Pironas/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Catalasa/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Aromatizantes/uso terapéutico , Glutatión/metabolismo , Inmunohistoquímica , Inflamación/metabolismo , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/metabolismo
6.
Z Naturforsch C J Biosci ; 71(5-6): 95-103, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27166720

RESUMEN

In light of the important antitumor activity of acylhydrazone compounds and based on our previous study, 18 new rotundic acid (RA) acylhydrazone derivatives were synthesized. All of the compounds were characterized by their spectroscopic data. The antiproliferative activity of the compounds was evaluated in vitro via the MTT method in three tumor cell lines, including A-375 (human malignant melanoma cells), SPC-A1 (human lung adenocarcinoma) and NCI-H446 (small cell lung cancer). The results showed that the antiproliferative activity of all of the compounds on the NCI-H446 cell line did not increase compared to RA, however, most of the derivatives exhibited higher activity against the A375 and SPC-A1 cell lines as compared to RA. Importantly, the antiproliferative activities of compounds 5a and 5b were the highest among the compounds, with IC(50) values <10 µM. Collectively, compounds 5a and 5b may act as potential anti-tumor agents in the future.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos , Hidrazonas , Neoplasias Pulmonares/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Triterpenos , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Melanoma/metabolismo , Melanoma/patología , Carcinoma Pulmonar de Células Pequeñas/metabolismo , Carcinoma Pulmonar de Células Pequeñas/patología , Triterpenos/síntesis química , Triterpenos/química , Triterpenos/farmacología
7.
Zhong Yao Cai ; 39(9): 2041-5, 2016 Sep.
Artículo en Zh | MEDLINE | ID: mdl-30209909

RESUMEN

Objective: To establish HPLC fingerprint in the root of Amorpha fruticosa, and simultaneously to determine the content of calycosin-7-O-ß-D-glucopyranoside, ononin, calycosin, formononetin. Methods: The analytical column was Diamonsil C18( 250 mm ×4. 6 mm,5 µm). The mobile phase was acetonitrile( A)-water( B)( containing 0. 2% phosphoric acid) in gradient elution, and the detection wavelength was set at 260 nm. "Chromatographic fingerprint similarity evaluation software "version( 2004A) was used to evaluate similarity for the ten batches medicinal materials,and SPSS software was used for cluster analysis. Results: The HPLC fingerprint of the root of Amorpha fruticosa was established with good separation, and four chemical compositions were determinated. 16 common peaks were defined in the HPLC fingerprint among the 10 batches of the root of Amorpa fruticosa. The similarity among them was more than0. 90. Conclusion: This analytical method has strong features,with a good repeatability and the method is simple, which can be used efficiently in the quality control in the root of Amorpha fruticosa.


Asunto(s)
Cromatografía Líquida de Alta Presión , Fabaceae , Medicamentos Herbarios Chinos , Glucósidos , Isoflavonas , Control de Calidad
8.
Sci Rep ; 14(1): 2189, 2024 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273010

RESUMEN

α-Enolase (ENO1) is a crucial molecular target for tumor therapy and has emerged as a research hotspot in recent decades. Here, we aimed to explore the role of ENO1 in bladder cancer (BLCA) and then construct a signature to predict the prognosis and treatment response of BLCA. Firstly, we found ENO1 was highly expressed in BLCA tissues, as verified by IHC, and was associated with poor prognosis. The analysis of the tumor immune microenvironment by bulk RNA-seq and scRNA-seq showed that ENO1 was associated with CD8+ T-cell exhaustion. Additionally, the results in vitro showed that ENO1 could promote the proliferation and invasion of BLCA cells. Then, the analysis of epithelial cells (ECs) revealed that ENO1 might promote BLCA progression by metabolism, the cell cycle and some carcinogenic pathways. A total of 249 hub genes were obtained from differentially expressed genes between ENO1-related ECs, and we used LASSO analysis to construct a novel signature that not only accurately predicted the prognosis of BLCA patients but also predicted the response to treatment for BLCA. Finally, we constructed a nomogram to better guide clinical application. In conclusion, through multi-omics analysis, we found that ENO1 was overexpressed in bladder cancer and associated with poor prognosis, CD8+ T-cell exhaustion and epithelial heterogeneity. Moreover, the prognosis and treatment of patients can be well predicted by constructing an epithelial-related prognostic signature.


Asunto(s)
Multiómica , Neoplasias de la Vejiga Urinaria , Humanos , Pronóstico , Neoplasias de la Vejiga Urinaria/genética , Nomogramas , Vejiga Urinaria , Microambiente Tumoral/genética , Proteínas de Unión al ADN/genética , Fosfopiruvato Hidratasa/genética , Biomarcadores de Tumor/genética , Proteínas Supresoras de Tumor/genética
9.
Sci Rep ; 14(1): 20654, 2024 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232038

RESUMEN

Small cell lung cancer (SCLC) is a very aggressive tumor. Abnormal expression of BUB1 has been reported in several cancer types, wherein it plays a range of functional roles. This work aimed to elucidate the functional significance and molecular impacts of BUB1 in SCLC. It was found that SCLC cell lines exhibited significant BUB1 upregulation relative to control bronchial cells using data from the Gene Expression Omnibus (GEO) database and verified by immunohistochemical staining. BUB1 was also found to promote the proliferative, migratory, invasive activity of SCLC cells, as shown by CCK-8, 3D migration wound-healing, and Transwell assays, as well as flow cytometry. Additionally, it was found that BUB1 silencing enhanced E-cadherin expression while suppressing N-cadherin, Vimentin, ZEB-1, and Snail levels, as shown by Western immunoblotting. The loss of BUB1 also reduced p-AKT and p-mTOR levels without altering total AKT or mTOR protein levels. In conclusion, BUB1 functions as an oncogenic promoter in SCLC, potentially regulating the epithelial-mesenchymal transition by activation of AKT/mTOR signaling.


Asunto(s)
Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , Proteínas Serina-Treonina Quinasas , Transducción de Señal , Carcinoma Pulmonar de Células Pequeñas , Humanos , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Carcinoma Pulmonar de Células Pequeñas/metabolismo , Carcinoma Pulmonar de Células Pequeñas/genética , Carcinoma Pulmonar de Células Pequeñas/patología , Serina-Treonina Quinasas TOR/metabolismo
10.
Front Immunol ; 15: 1363834, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38633247

RESUMEN

Background: Hyaluronan-mediated motility receptor (HMMR) is overexpressed in multiple carcinomas and influences the development and treatment of several cancers. However, its role in hepatocellular carcinoma (HCC) remains unclear. Methods: The "limma" and "GSVA" packages in R were used to perform differential expression analysis and to assess the activity of signalling pathways, respectively. InferCNV was used to infer copy number variation (CNV) for each hepatocyte and "CellChat" was used to analyse intercellular communication networks. Recursive partitioning analysis (RPA) was used to re-stage HCC patients. The IC50 values of various drugs were evaluated using the "pRRophetic" package. In addition, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to confirm HMMR expression in an HCC tissue microarray. Flow cytometry (FCM) and cloning, Edu and wound healing assays were used to explore the capacity of HMMR to regulate HCC tumour. Results: Multiple cohort studies and qRT-PCR demonstrated that HMMR was overexpressed in HCC tissue compared with normal tissue. In addition, HMMR had excellent diagnostic performance. HMMR knockdown inhibited the proliferation and migration of HCC cells in vitro. Moreover, high HMMR expression was associated with "G2M checkpoint" and "E2F targets" in bulk RNA and scRNA-seq, and FCM confirmed that HMMR could regulate the cell cycle. In addition, HMMR was involved in the regulation of the tumour immune microenvironment via immune cell infiltration and intercellular interactions. Furthermore, HMMR was positively associated with genomic heterogeneity with patients with high HMMR expression potentially benefitting more from immunotherapy. Moreover, HMMR was associated with poor prognosis in patients with HCC and the re-staging by recursive partitioning analysis (RPA) gave a good prognosis prediction value and could guide chemotherapy and targeted therapy. Conclusion: The results of the present study show that HMMR could play a role in the diagnosis, prognosis, and treatments of patients with HCC based on bulk RNA-seq and scRAN-seq analyses and is a promising molecular marker for HCC.


Asunto(s)
Carcinoma Hepatocelular , Receptores de Hialuranos , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Variaciones en el Número de Copia de ADN , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Análisis de Expresión Génica de una Sola Célula , Microambiente Tumoral/genética
11.
Exploration (Beijing) ; 4(2): 20230114, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38855613

RESUMEN

Multi-scale simulation is an important basis for constructing digital batteries to improve battery design and application. LiF-rich solid electrolyte interphase (SEI) is experimentally proven to be crucial for the electrochemical performance of lithium metal batteries. However, the LiF-rich SEI is sensitive to various electrolyte formulas and the fundamental mechanism is still unclear. Herein, the structure and formation mechanism of LiF-rich SEI in different electrolyte formulas have been reviewed. On this basis, it further discussed the possible filming mechanism of LiF-rich SEI determined by the initial adsorption of the electrolyte-derived species on the lithium metal anode (LMA). It proposed that individual LiF species follow the Volmer-Weber mode of film growth due to its poor wettability on LMA. Whereas, the synergistic adsorption of additive-derived species with LiF promotes the Frank-Vander Merwe mode of film growth, resulting in uniform LiF deposition on the LMA surface. This perspective provides new insight into the correlation between high LiF content, wettability of LiF, and highperformance of uniform LiF-rich SEI. It disclosed the importance of additive assistant synergistic adsorption on the uniform growth of LiF-rich SEI, contributing to the reasonable design of electrolyte formulas and high-performance LMA, and enlightening the way for multi-scale simulation of SEI.

12.
Comput Methods Programs Biomed ; 244: 107969, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38064958

RESUMEN

BACKGROUND AND OBJECTIVE: The rapid on-site evaluation (ROSE) technique improves pancreatic cancer diagnosis by enabling immediate analysis of fast-stained cytopathological images. Automating ROSE classification could not only reduce the burden on pathologists but also broaden the application of this increasingly popular technique. However, this approach faces substantial challenges due to complex perturbations in color distribution, brightness, and contrast, which are influenced by various staining environments and devices. Additionally, the pronounced variability in cancerous patterns across samples further complicates classification, underscoring the difficulty in precisely identifying local cells and establishing their global relationships. METHODS: To address these challenges, we propose an instance-aware approach that enhances the Vision Transformer with a novel shuffle instance strategy (SI-ViT). Our approach presents a shuffle step to generate bags of shuffled instances and corresponding bag-level soft-labels, allowing the model to understand relationships and distributions beyond the limited original distributions. Simultaneously, combined with an un-shuffle step, the traditional ViT can model the relationships corresponding to the sample labels. This dual-step approach helps the model to focus on inner-sample and cross-sample instance relationships, making it potent in extracting diverse image patterns and reducing complicated perturbations. RESULTS: Compared to state-of-the-art methods, significant improvements in ROSE classification have been achieved. Aiming for interpretability, equipped with instance shuffling, SI-ViT yields precise attention regions that identifying cancer and normal cells in various scenarios. Additionally, the approach shows excellent potential in pathological image analysis through generalization validation on other datasets. CONCLUSIONS: By proposing instance relationship modeling through shuffling, we introduce a new insight in pathological image analysis. The significant improvements in ROSE classification leads to protential AI-on-site applications in pancreatic cancer diagnosis. The code and results are publicly available at https://github.com/sagizty/MIL-SI.


Asunto(s)
Neoplasias Pancreáticas , Evaluación in Situ Rápida , Humanos , Páncreas , Neoplasias Pancreáticas/diagnóstico por imagen , Concienciación , Suministros de Energía Eléctrica
13.
Biomater Sci ; 12(17): 4363-4375, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39023223

RESUMEN

Despite recent technological advances in drug discovery, the success rate for neurotherapeutics remains alarmingly low compared to treatments for other areas of the body. One of the biggest challenges for delivering therapeutics to the central nervous system (CNS) is the presence of the blood-brain barrier (BBB). In vitro blood-brain barrier models with high predictability are essential to aid in designing parameters for new therapeutics, assess their ability to cross the BBB, and investigate therapeutic strategies that can be employed to enhance transport. Here, we demonstrate the development of a 3D printable hydrogel blood-brain barrier model that mimics the cellular composition and structure of the blood-brain barrier with human brain endothelial cells lining the surface, pericytes in direct contact with the endothelial cells on the abluminal side of the endothelium, and astrocytes in the surrounding printed bulk matrix. We introduce a simple, static printed hemi-cylinder model to determine design parameters such as media selection, co-culture ratios, and cell incorporation timing in a resource-conservative and high-throughput manner. Presence of cellular adhesion junction, VE-Cadherin, efflux transporters, P-glycoprotein (P-gp) and Breast cancer resistance protein (BCRP), and receptor-mediated transporters, Transferrin receptor (TfR) and low-density lipoprotein receptor-related protein 1 (LRP1) were confirmed via immunostaining demonstrating the ability of this model for screening in therapeutic strategies that rely on these transport systems. Design parameters determined in the hemi-cylinder model were translated to a more complex, perfusable vessel model to demonstrate its utility for determining barrier function and assessing permeability to model therapeutic compounds. This 3D-printed blood-brain barrier model represents one of the first uses of projection stereolithography to fabricate a perfusable blood-brain barrier model, enabling the patterning of complex vessel geometries and precise arrangement of cell populations. This model demonstrates potential as a new platform to investigate the delivery of neurotherapeutic compounds and drug delivery strategies through the blood-brain barrier, providing a useful in vitro screening tool in central nervous system drug discovery and development.


Asunto(s)
Barrera Hematoencefálica , Células Endoteliales , Impresión Tridimensional , Barrera Hematoencefálica/metabolismo , Humanos , Células Endoteliales/metabolismo , Células Endoteliales/citología , Técnicas de Cocultivo , Hidrogeles/química , Modelos Biológicos , Astrocitos/metabolismo , Astrocitos/citología , Pericitos/metabolismo , Pericitos/citología
14.
Foods ; 13(17)2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39272620

RESUMEN

The ratiometric fluorescent probe UiO-OH@Tb, a zirconium-based MOF functionalized with Tb3+, was synthesized using a hydrothermal method. This probe employs the fluorescence resonance energy transfer (FRET) mechanism between Tb3+ and malachite green (MG) for the double-inverse signal ratiometric fluorescence detection of MG. The probe's color shifts from lime green to blue with an increasing concentration of MG. In contrast, the monometallic MOFs' (UiO-OH) probe shows only blue fluorescence quenching due to the inner filter effect (IFE) after interacting with MG. Additionally, the composite fluorescent probe (UiO-OH@Tb) exhibits superior sensitivity, with a detection limit (LOD) of 0.19 µM, which is significantly lower than that of the monometallic MOFs (25 µM). Moreover, the content of MG can be detected on-site (LOD = 0.94 µM) using the RGB function of smartphones. Hence, the UiO-OH@Tb probe is proven to be an ideal material for MG detection, demonstrating significant practical value in real-world applications.

15.
IEEE Trans Med Imaging ; PP2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39024079

RESUMEN

Histopathological examinations heavily rely on hematoxylin and eosin (HE) and immunohistochemistry (IHC) staining. IHC staining can offer more accurate diagnostic details but it brings significant financial and time costs. Furthermore, either re-staining HE-stained slides or using adjacent slides for IHC may compromise the accuracy of pathological diagnosis due to information loss. To address these challenges, we develop PST-Diff, a method for generating virtual IHC images from HE images based on diffusion models, which allows pathologists to simultaneously view multiple staining results from the same tissue slide. To maintain the pathological consistency of the stain transfer, we propose the asymmetric attention mechanism (AAM) and latent transfer (LT) module in PST-Diff. Specifically, the AAM can retain more local pathological information of the source domain images through the design of asymmetric attention mechanisms, while ensuring the model's flexibility in generating virtual stained images that highly confirm to the target domain. Subsequently, the LT module transfers the implicit representations across different domains, effectively alleviating the bias introduced by direct connection and further enhancing the pathological consistency of PST-Diff. Furthermore, to maintain the structural consistency of the stain transfer, the conditional frequency guidance (CFG) module is proposed to precisely control image generation and preserve structural details according to the frequency recovery process. To conclude, the pathological and structural consistency constraints provide PST-Diff with effectiveness and superior generalization in generating stable and functionally pathological IHC images with the best evaluation score. In general, PST-Diff offers prospective application in clinical virtual staining and pathological image analysis.

16.
Bioorg Med Chem Lett ; 23(9): 2543-7, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23558236

RESUMEN

In the present investigation, 16 new rotundic acid (RA) derivatives modified at the C-3, C-23 and C-28 positions were synthesized. The cytotoxicities of the derivatives were evaluated against HeLa, A375, HepG2, SPC-A1 and NCI-H446 human tumor cell lines by MTT assay. Among these derivatives, compounds 4-7 exhibited stronger cell growth inhibitory than RA and compound 4 was found to be the best inhibition activity on five human tumor cell lines with IC50 <10 µM. The apoptosis mechanism of compound 4 in HeLa cells was investigated by western blot analysis. The results indicated that compound 4 could induce apoptosis through increasing protein expression of cleaved caspase-3 and Bax, and decreasing protein expression of Bcl-2. In summary, the present work suggests that compound 4 might serve as an effective chemotherapeutic candidate.


Asunto(s)
Antineoplásicos/síntesis química , Diseño de Fármacos , Triterpenos/química , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Células HeLa , Células Hep G2 , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Triterpenos/síntesis química , Triterpenos/farmacología , Proteína X Asociada a bcl-2/metabolismo
17.
J Vis Exp ; (199)2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37843292

RESUMEN

For a cell model to be viable for drug screening, the system must meet throughput and homogeneity requirements alongside having an efficient development time. However, many published 3D models do not satisfy these criteria. This therefore, limits their usefulness in early drug discovery applications. Three-dimensional (3D) bioprinting is a novel technology that can be applied to the development of 3D models to expedite development time, increase standardization, and increase throughput. Here, we present a protocol to develop 3D bioprinted coculture models of human induced pluripotent stem cell (iPSC)-derived glutamatergic neurons and astrocytes. These cocultures are embedded within a hydrogel matrix of bioactive peptides, full-length extracellular matrix (ECM) proteins, and with a physiological stiffness of 1.1 kPa. The model can be rapidly established in 96-well and 384-well formats and produces an average post-print viability of 72%. The astrocyte-to-neuron ratio in this model is shown to be 1:1.5, which is within the physiological range for the human brain. These 3D bioprinted cell populations also show expression of mature neural cell type markers and growth of neurite and astrocyte projections within 7 days of culture. As a result, this model is suitable for analysis using cell dyes and immunostaining techniques alongside neurite outgrowth assays. The ability to produce these physiologically representative models at scale makes them ideal for use in medium-to-high throughput screening assays for neuroscience targets.


Asunto(s)
Bioimpresión , Células Madre Pluripotentes Inducidas , Humanos , Técnicas de Cocultivo , Astrocitos , Bioimpresión/métodos , Neuronas , Impresión Tridimensional
18.
Artículo en Inglés | MEDLINE | ID: mdl-37831570

RESUMEN

The blood pressure (BP) waveform is a vital source of physiological and pathological information concerning the cardiovascular system. This study proposes a novel attention-guided conditional generative adversarial network (cGAN), named PPG2BP-cGAN, to estimate BP waveforms based on photoplethysmography (PPG) signals. The proposed model comprises a generator and a discriminator. Specifically, the UNet3+-based generator integrates a full-scale skip connection structure with a modified polarized self-attention module based on a spatial-temporal attention mechanism. Additionally, its discriminator comprises PatchGAN, which augments the discriminative power of the generated BP waveform by increasing the perceptual field through fully convolutional layers. We demonstrate the superior BP waveform prediction performance of our proposed method compared to state-of-the-art (SOTA) techniques on two independent datasets. Our approach first pre-trained on a dataset containing 683 subjects and then tested on a public dataset. Experimental results from the Multi-parameter Intelligent Monitoring in Intensive Care dataset show that the proposed method achieves a root mean square error of 3.54, mean absolute error of 2.86, and Pearson coefficient of 0.99 for BP waveform estimation. Furthermore, the estimation errors (mean error ± standard deviation error) for systolic BP and diastolic BP are 0.72 ± 4.34 mmHg and 0.41 ± 2.48 mmHg, respectively, meeting the American Association for the Advancement of Medical Instrumentation standard. Our approach exhibits significant superiority over SOTA techniques on independent datasets, thus highlighting its potential for future applications in continuous cuffless BP waveform measurement.

19.
Artículo en Inglés | MEDLINE | ID: mdl-37368801

RESUMEN

Radiomics refers to the high-throughput extraction of quantitative features from medical images, and is widely used to construct machine learning models for the prediction of clinical outcomes, while feature engineering is the most important work in radiomics. However, current feature engineering methods fail to fully and effectively utilize the heterogeneity of features when dealing with different kinds of radiomics features. In this work, latent representation learning is first presented as a novel feature engineering approach to reconstruct a set of latent space features from original shape, intensity and texture features. This proposed method projects features into a subspace called latent space, in which the latent space features are obtained by minimizing a unique hybrid loss function including a clustering-like loss and a reconstruction loss. The former one ensures the separability among each class while the latter one narrows the gap between the original features and latent space features. Experiments were performed on a multi-center non-small cell lung cancer (NSCLC) subtype classification dataset from 8 international open databases. Results showed that compared with four traditional feature engineering methods (baseline, PCA, Lasso and L2,1-norm minimization), latent representation learning could significantly improve the classification performance of various machine learning classifiers on the independent test set (all p<0.001). Further on two additional test sets, latent representation learning also showed a significant improvement in generalization performance. Our research shows that latent representation learning is a more effective feature engineering method, which has the potential to be used as a general technology in a wide range of radiomics researches.

20.
APL Bioeng ; 7(4): 046113, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38046544

RESUMEN

There is critical need for a predictive model of human cardiac physiology in drug development to assess compound effects on human tissues. In vitro two-dimensional monolayer cultures of cardiomyocytes provide biochemical and cellular readouts, and in vivo animal models provide information on systemic cardiovascular response. However, there remains a significant gap in these models due to their incomplete recapitulation of adult human cardiovascular physiology. Recent efforts in developing in vitro models from engineered heart tissues have demonstrated potential for bridging this gap using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in three-dimensional tissue structure. Here, we advance this paradigm by implementing FRESH™ 3D bioprinting to build human cardiac tissues in a medium throughput, well-plate format with controlled tissue architecture, tailored cellular composition, and native-like physiological function, specifically in its drug response. We combined hiPSC-CMs, endothelial cells, and fibroblasts in a cellular bioink and FRESH™ 3D bioprinted this mixture in the format of a thin tissue strip stabilized on a tissue fixture. We show that cardiac tissues could be fabricated directly in a 24-well plate format were composed of dense and highly aligned hiPSC-CMs at >600 million cells/mL and, within 14 days, demonstrated reproducible calcium transients and a fast conduction velocity of ∼16 cm/s. Interrogation of these cardiac tissues with the ß-adrenergic receptor agonist isoproterenol showed responses consistent with positive chronotropy and inotropy. Treatment with calcium channel blocker verapamil demonstrated responses expected of hiPSC-CM derived cardiac tissues. These results confirm that FRESH™ 3D bioprinted cardiac tissues represent an in vitro platform that provides data on human physiological response.

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