RESUMEN
RNA N4-acetylcytidine (ac4C) modification is increasingly recognized as an important layer of gene regulation; however, the involvement of ac4C in pain regulation has not been studied. Here, we report that N-acetyltransferase 10 protein (NAT10; the only known ac4C "writer") contributes to the induction and development of neuropathic pain in an ac4C-dependent manner. Peripheral nerve injury increases the levels of NAT10 expression and overall ac4C in injured dorsal root ganglia (DRGs). This upregulation is triggered by the activation of upstream transcription factor 1 (USF1), a transcription factor that binds to the Nat10 promoter. Knock-down or genetic deletion of NAT10 in the DRG abolishes the gain of ac4C sites in Syt9 mRNA and the augmentation of SYT9 protein, resulting in a marked antinociceptive effect in nerve-injured male mice. Conversely, mimicking NAT10 upregulation in the absence of injury evokes the elevation of Syt9 ac4C and SYT9 protein and induces the genesis of neuropathic-pain-like behaviors. These findings demonstrate that USF1-governed NAT10 regulates neuropathic pain by targeting Syt9 ac4C in peripheral nociceptive sensory neurons. Our findings establish NAT10 as a critical endogenous initiator of nociceptive behavior and a promising new target for treating neuropathic pain.SIGNIFICANCE STATEMENT The cytidine N4-acetylcytidine (ac4C), a new epigenetic RNA modification, is crucial for the translation and stability of mRNA, but its role for chronic pain remains unclear. Here, we demonstrate that N-acetyltransferase 10 (NAT10) acts as ac4C N-acetyltransferase and plays an important role in the development and maintenance of neuropathic pain. NAT10 was upregulated via the activation of the transcription factor upstream transcription factor 1 (USF1) in the injured dorsal root ganglion (DRG) after peripheral nerve injury. Since pharmacological or genetic deleting NAT10 in the DRG attenuated the nerve injury-induced nociceptive hypersensitivities partially through suppressing Syt9 mRNA ac4C and stabilizing SYT9 protein level, NAT10 may serve as an effective and novel therapeutic target for neuropathic pain.
Asunto(s)
Neuralgia , Traumatismos de los Nervios Periféricos , Animales , Masculino , Ratones , Acetiltransferasas/metabolismo , Citidina/farmacología , Citidina/genética , Citidina/metabolismo , Ganglios Espinales/metabolismo , Neuralgia/etiología , Neuralgia/metabolismo , Traumatismos de los Nervios Periféricos/complicaciones , Traumatismos de los Nervios Periféricos/metabolismo , ARN , ARN Mensajero/metabolismo , Células Receptoras Sensoriales/metabolismo , Factores de Transcripción/metabolismoRESUMEN
Dysfunctional gene expression in nociceptive pathways plays a critical role in the development and maintenance of neuropathic pain. Super enhancers (SEs), composed of a large cluster of transcriptional enhancers, are emerging as new players in the regulation of gene expression. However, whether SEs participate in nociceptive responses remains unknown. Here, we report a spinal-specific SE (SS-SE) that regulates chronic constriction injury (CCI)-induced neuropathic pain by driving Ntmt1 and Prrx2 transcription in dorsal horn neurons. Peripheral nerve injury significantly enhanced the activity of SS-SE and increased the expression of NTMT1 and PRRX2 in the dorsal horn of male mice in a bromodomain-containing protein 4 (BRD4)-dependent manner. Both intrathecal administration of a pharmacological BRD4 inhibitor JQ1 and CRISPR-Cas9-mediated SE deletion abolished the increased NTMT1 and PRRX2 in CCI mice and attenuated their nociceptive hypersensitivities. Furthermore, knocking down Ntmt1 or Prrx2 with siRNA suppressed the injury-induced elevation of phosphorylated extracellular-signal-regulated kinase (p-ERK) and glial fibrillary acidic protein (GFAP) expression in the dorsal horn and alleviated neuropathic pain behaviors. Mimicking the increase in spinal Ntmt1 or Prrx2 in naive mice increased p-ERK and GFAP expression and led to the genesis of neuropathic pain-like behavior. These results redefine our understanding of the regulation of pain-related genes and demonstrate that BRD4-driven increases in SS-SE activity is responsible for the genesis of neuropathic pain through the governance of NTMT1 and PRRX2 expression in dorsal horn neurons. Our findings highlight the therapeutic potential of BRD4 inhibitors for the treatment of neuropathic pain.SIGNIFICANCE STATEMENT SEs drive gene expression by recruiting master transcription factors, cofactors, and RNA polymerase, but their role in the development of neuropathic pain remains unknown. Here, we report that the activity of an SS-SE, located upstream of the genes Ntmt1 and Prrx2, was elevated in the dorsal horn of mice with neuropathic pain. SS-SE contributes to the genesis of neuropathic pain by driving expression of Ntmt1 and Prrx2 Both inhibition of SS-SE with a pharmacological BRD4 inhibitor and genetic deletion of SS-SE attenuated pain hypersensitivities. This study suggests an effective and novel therapeutic strategy for neuropathic pain.
Asunto(s)
Hipersensibilidad , Neuralgia , Ratas , Masculino , Ratones , Animales , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Hiperalgesia/metabolismo , Ratas Sprague-Dawley , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Neuralgia/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Hipersensibilidad/metabolismoRESUMEN
Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the bloodâbrain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.
Asunto(s)
Trampas Extracelulares , Accidente Cerebrovascular , Humanos , Trampas Extracelulares/metabolismo , Accidente Cerebrovascular/terapia , Animales , Barrera Hematoencefálica/metabolismo , NeutrófilosRESUMEN
Abnormal growth of airway smooth muscle cells is one of the key features in asthmatic airway remodeling, which is associated with asthma severity. The mechanisms underlying inappropriate airway smooth muscle cell growth in asthma remain largely unknown. Myocd has been reported to act as a key transcriptional coactivator in promoting airway-specific smooth muscle development in fetal lungs. Whether Myocd controls airway smooth muscle remodeling in asthma has not been investigated. Mice with lung mesenchyme-specific deletion of Myocd after lung development were generated, and a chronic asthma model was established by sensitizing and challenging the mice with ovalbumin for a prolonged period. Comparison of the asthmatic pathology between the Myocd knockout mice and the wild-type controls revealed that abrogation of Myocd mitigated airway smooth muscle cell hypertrophy and hyperplasia, accompanied by reduced peri-airway inflammation, decreased fibrillar collagen deposition on airway walls, and attenuation of abnormal mucin production in airway epithelial cells. Our study indicates that Myocd is a key transcriptional coactivator involved in asthma airway remodeling. Inhibition of Myocd in asthmatic airways may be an effective approach to breaking the vicious cycle of asthmatic progression, providing a novel strategy in treating severe and persistent asthma. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias) , Asma , Proteínas Nucleares , Animales , Ratones , Asma/genética , Asma/metabolismo , Modelos Animales de Enfermedad , Inflamación/patología , Pulmón/patología , Ratones Endogámicos BALB C , Ratones Noqueados , Miocitos del Músculo Liso/patología , Proteínas Nucleares/metabolismoRESUMEN
As an increasing number of renewable energy generators are integrated into the electrical grid, the necessity to add new transmission lines to facilitate power transfer and ensure grid stability becomes paramount. However, the addition of new transmission lines to the existing grid topology can lead to the emergence of Braess's paradox or even trigger grid failures. Hence, predicting where to add transmission lines to guarantee stable grid operation is of utmost importance. In this context, we employ deep learning to address this challenge and propose a graph neural network-based method for predicting Braess's paradox in electrical grids, framing the problem of adding new transmission lines causing Braess's paradox as a graph classification task. Taking into consideration the topological and electrical attributes of the grid, we select node features such as degree, closeness centrality, and power values. This approach assists the model in better understanding the relationships between nodes, enhancing the model's representational capabilities. Furthermore, we apply layered adaptive weighting to the output of the graph isomorphism network to emphasize the significance of hierarchical information that has a greater impact on the output, thus improving the model's generalization across electrical grids of varying scales. Experimental results on the IEEE 39, IEEE 57, and IEEE 118 standard test systems demonstrate the efficiency of the proposed method, achieving prediction accuracies of 93.8%, 88.8%, and 88.1%, respectively. Model visualization and ablation studies further validate the effectiveness of this approach.
RESUMEN
Epilepsy is a common neurological disorder, and its diagnosis mainly relies on the analysis of electroencephalogram (EEG) signals. However, the raw EEG signals contain limited recognizable features, and in order to increase the recognizable features in the input of the network, the differential features of the signals, the amplitude spectrum and the phase spectrum in the frequency domain are extracted to form a two-dimensional feature vector. In order to solve the problem of recognizing multimodal features, a neural network model based on a multimodal dual-stream network is proposed, which uses a mixture of one-dimensional convolution, two-dimensional convolution and LSTM neural networks to extract the spatial features of the EEG two-dimensional vectors and the temporal features of the signals, respectively, and combines the advantages of the two networks, using the hybrid neural network to extract both the temporal and spatial features of the signals at the same time. In addition, a channel attention module was used to focus the model on features related to seizures. Finally, multiple sets of experiments were conducted on the Bonn and New Delhi data sets, and the highest accuracy rates of 99.69% and 97.5% were obtained on the test set, respectively, verifying the superiority of the proposed model in the task of epileptic seizure detection.
Asunto(s)
Electroencefalografía , Epilepsia , Redes Neurales de la Computación , Convulsiones , Humanos , Electroencefalografía/métodos , Epilepsia/diagnóstico , Epilepsia/fisiopatología , Convulsiones/diagnóstico , Convulsiones/fisiopatología , Procesamiento de Señales Asistido por Computador , AlgoritmosRESUMEN
Alpha-1 antitrypsin-overexpressing mesenchymal stromal/stem cells (AAT-MSCs) showed improved innate properties with a faster proliferation rate when studied for their protective effects in mouse models of diseases. Here, we investigated the potential mechanism(s) by which AAT gene insertion increases MSC proliferation. Human bone marrow-derived primary or immortalized MSCs (iMSCs) or AAT-MSCs (iAAT-MSCs) were used in the study. Cell proliferation was measured by cell counting and cell cycle analysis. Possible pathways involved in the pro-proliferation effect of AAT were investigated by measuring mRNA and protein expression of key cell cycle genes. Interval cell counting showed increased proliferation in AAT-MSCs or iAAT-MSCs compared to their corresponding MSC controls. Cell cycle analysis revealed more cells progressing into the S and G2/M phases in iAAT-MSCs, with a notable increase in the cell cycle protein, Cyclin D1. Moreover, treatment with Cyclin D1 inhibitors showed that the increase in proliferation is due to Cyclin D1 and that the AAT protein is upstream and a positive regulator of Cyclin D1. Furthermore, AAT's effect on Cyclin D1 is independent of the Wnt signaling pathway as there were no differences in the expression of regulatory proteins, including GSK3ß and ß-Catenin in iMSC and iAAT-MSCs. In summary, our results indicate that AAT gene insertion in an immortalized MSC cell line increases cell proliferation and growth by increasing Cyclin D1 expression and consequently causing cells to progress through the cell cycle at a significantly faster rate.
Asunto(s)
Ciclina D1 , Células Madre Mesenquimatosas , alfa 1-Antitripsina , Animales , Humanos , Ratones , Proliferación Celular/genética , Ciclina D1/genética , Ciclina D1/metabolismo , Células Madre Mesenquimatosas/metabolismo , Regulación hacia Arriba , Vía de Señalización Wnt , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismoRESUMEN
We developed the Stem Cell Educator therapy among multiple clinical trials based on the immune modulations of multipotent cord blood-derived stem cells (CB-SCs) on different compartments of immune cells, such as T cells and monocytes/macrophages, in type 1 diabetes and other autoimmune diseases. However, the effects of CB-SCs on the B cells remained unclear. To better understand the molecular mechanisms underlying the immune education of CB-SCs, we explored the modulations of CB-SCs on human B cells. CB-SCs were isolated from human cord blood units and confirmed by flow cytometry with different markers for their purity. B cells were purified by using anti-CD19 immunomagnetic beads from human peripheral blood mononuclear cells (PBMCs). Next, the activated B cells were treated in the presence or absence of coculture with CB-SCs for 7 days before undergoing flow cytometry analysis of phenotypic changes with different markers. Reverse transcription-polymerase chain reaction (RT-PCR) was utilized to evaluate the levels of galectin expressions on CB-SCs with or without treatment of activated B cells in order to find the key galectin that was contributing to the B-cell modulation. Flow cytometry demonstrated that the proliferation of activated B cells was markedly suppressed in the presence of CB-SCs, leading to the downregulation of immunoglobulin production from the activated B cells. Phenotypic analysis revealed that treatment with CB-SCs increased the percentage of IgD+CD27- naïve B cells, but decreased the percentage of IgD-CD27+ switched B cells. The transwell assay showed that the immune suppression of CB-SCs on B cells was dependent on the galectin-9 molecule, as confirmed by the blocking experiment with the anti-galectin-9 monoclonal antibody. Mechanistic studies demonstrated that both calcium levels of cytoplasm and mitochondria were downregulated after the treatment with CB-SCs, causing the decline in mitochondrial membrane potential in the activated B cells. Western blot exhibited that the levels of phosphorylated Akt and Erk1/2 signaling proteins in the activated B cells were also markedly reduced in the presence of CB-SCs. CB-SCs displayed multiple immune modulations on B cells through the galectin-9-mediated mechanism and calcium flux/Akt/Erk1/2 signaling pathways. The data advance our current understanding of the molecular mechanisms underlying the Stem Cell Educator therapy to treat autoimmune diseases in clinics.
Asunto(s)
Enfermedades Autoinmunes , Leucocitos Mononucleares , Humanos , Sangre Fetal , Calcio/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Enfermedades Autoinmunes/metabolismo , Células Madre/metabolismo , Galectinas/metabolismoRESUMEN
Programmed death ligand-1 (PD-L1) is highly expressed in a variety of cancer cells and suggests a poorer prognosis for patients. The natural compound isorhamnetin (ISO) shows promise in treating cancers and causing damage to canine mammary tumor (CMT) cells. We investigated the mechanism of ISO in reducing PD-L1 expression in CMT cells. Clustered, regularly interspaced short palindromic repeat-associated protein 9 (CRISPR/Cas9) was used to mediate CD274 knockout in U27 cells. Then, monoclonal cells were screened and cultured. Nucleotide sequencing and expression of PD-L1 were detected. Additionally, we examined cell migration, invasion, and damage. Immunofluorescent staining of PD-L1 was examined in U27 cells. The signaling pathways were measured by Western blotting. Murine xenotransplantation models and murine immunocompetent allograft mammary tumor models were established to evaluate the effect of ISO therapy. Expression of Ki-67, caspase3, and PD-L1 were analyzed by immunohistochemistry. A pull-down assay was used to explore which proteins could bind to ISO. Canine EGFR protein was purified and used to detect whether it directly binds to ISO using a surface plasmon resonance assay. ISO inhibited the EGFR-STAT3-PD-L1 signaling pathway and blocked cancer growth, significantly increasing the survival rate of healthy cells. The cell membrane receptor EGFR was identified as a direct target of ISO. ISO could be exploited as an antineoplastic treatment of CMT by targeting EGFR to suppress PD-L1 expression.
Asunto(s)
Antígeno B7-H1 , Neoplasias de la Mama , Quercetina , Animales , Perros , Ratones , Antígeno B7-H1/genética , Receptores ErbB/genética , Ligandos , Quercetina/análogos & derivados , Transducción de Señal , Factor de Transcripción STAT3 , Neoplasias de la Mama/veterinariaRESUMEN
OBJECTIVES: This study aimed to investigate the correlations between carotid intima-media thickness (IMT) and systemic immune inflammation index (SII), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte (NLR) ratio. MATERIALS AND METHODS: This was a cross-sectional study enrolling a total of 582 middle-aged and elderly patients. The correlations between SII, PLR, and NLR with IMT were assessed using logistic regression models, which were subsequently incorporated into the underlying models with traditional risk factors and their predictive values for IMT. RESULTS: NLR exhibited a significant correlation with IMT in the simple regression analysis (ß = 0.01, 95 %CI= 0.00-0.02, p < 0.05). After controlling for potential confounding variables in the multivariate analysis, the association between NLR and both Maximum IMT [ß = 0.04, 95 %CI = 0.02-0.07, p = 0.0006] and Mean IMT [ß = 0.05, 95 %CI = 0.02-0.07, p = 0.0001] remained statistically significant. Additionally, PLR was found to be a significant independent predictor of Maximum IMT [ß = 0.04, 95 % CI =0.00-0.07, p = 0.0242] and Mean IMT [ß = 0.04, 95 % CI = 0.01-0.07, p = 0.0061]. Similarly, SII was identified as an independent predictor of Maximum IMT [ß = 1.87, 95 % CI =1.24, p = 0.0003]. The study found a significant positive correlation between Maximum IMT and the levels NLR, PLR, and SII. Specifically, in the Maximum IMT group, higher quartiles of NLR, PLR, and SII were associated with increased odds ratios (OR) for elevated IMT levels, with statistically significant results for NLR (Q4vsQ1: OR 3.87, 95 % CI 1.81-8.29), PLR (Q4vsQ1: OR 2.84, 95 % CI 1.36-5.95), and SII (Q4vsQ1: OR 2.64, 95 % CI 1.30-5.37). Finally, the inclusion of NLR, PLR, and NLR+PLR+SII in the initial model with traditional risk factors resulted in a marginal improvement in the predictive ability for Maximum IMT, as evidenced by the net reclassification index (p < 0.05). CONCLUSIONS: This study discovered a positive correlation between SII, PLR, NLR, and IMT, which are likely to emerge as new predictors for IMT thickening. These findings lay a theoretical reference for future predictive research and pathophysiological research on carotid intima-media thickening.
Asunto(s)
Plaquetas , Enfermedades de las Arterias Carótidas , Grosor Intima-Media Carotídeo , Linfocitos , Neutrófilos , Valor Predictivo de las Pruebas , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Transversales , Anciano , Recuento de Linfocitos , Linfocitos/patología , Recuento de Plaquetas , Factores de Riesgo , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/sangre , Plaquetas/patología , Factores de Edad , Inflamación/sangre , Inflamación/diagnóstico , Medición de RiesgoRESUMEN
Flexible and transparent surface-enhanced Raman scattering (SERS) substrates have attracted considerable attention for their ability to enable the direct in situ detection of analytes on curved surfaces. However, the curvature of an object can impact the signal enhancement of SERS during the measurement process. Herein, we propose a simple approach for fabricating a curvature-insensitive transparent SERS substrate by depositing silver nanoparticles (Ag NPs) onto a large-area wrinkled polystyrene/polydimethylsiloxane (Ag NP@W-PS/PDMS) bilayer film. Using rhodamine 6G (R6G) as a probe molecule, the optimized Ag NP@W-PS/PDMS film demonstrates a high analytical enhancement factor (AEF) of 4.83 × 105, excellent uniformity (RSD = 7.85%) and reproducibility (RSD = 3.09%), as well as superior mechanical flexibility. Additionally, in situ measurements of malachite green (MG) on objects with diverse curvatures, including fish, apple, and blueberry, are conducted using a portable Raman system, revealing a consistent SERS enhancement. Furthermore, a robust linear relationship (R2 ≥ 0.990) between Raman intensity and the logarithmic concentration of MG detected from these objects is achieved. These results demonstrate the tremendous potential of the developed curvature-insensitive SERS substrate as a point-of-care testing (POCT) platform for identifying analytes on irregular objects.
RESUMEN
Repetitive DNA sequences are often associated with chromosomal rearrangements in cancers. Conventionally, single-strand annealing (SSA) is thought to mediate homology-directed repair of double-strand breaks (DSBs) between two repeats, causing repeat-mediated deletion (RMD). In this report, we demonstrate that break-induced replication (BIR) is used predominantly over SSA in mammalian cells for mediating RMD, especially when repeats are far apart. We show that SSA becomes inefficient in mammalian cells when the distance between the DSBs and the repeats is increased to the 1-2 kb range, while BIR-mediated RMD (BIR/RMD) can act over a long distance (e.g., ~ 100-200 kb) when the DSB is close to one repeat. Importantly, oncogene expression potentiates BIR/RMD but not SSA, and BIR/RMD is used more frequently at single-ended DSBs formed at collapsed replication forks than at double-ended DSBs. In contrast to short-range SSA, H2AX is required for long-range BIR/RMD, and sequence divergence strongly suppresses BIR/RMD in a manner partially dependent on MSH2. Our finding that BIR/RMD has a more important role than SSA in mammalian cells has a significant impact on the understanding of repeat-mediated rearrangements associated with oncogenesis.
Asunto(s)
Roturas del ADN de Cadena Simple , Reparación del ADN , Replicación del ADN , Proteínas de Unión al ADN , Eliminación de Secuencia , Animales , Secuencia de Bases , Aberraciones Cromosómicas , Células Madre Embrionarias , Técnicas de Inactivación de Genes , Células HEK293 , Histonas/genética , Humanos , Ratones , Proteína 2 Homóloga a MutS/genética , Neoplasias/genética , Oncogenes/genética , Reparación del ADN por RecombinaciónRESUMEN
Porous noble metal nanoparticles have received particular attention recently for their unique optical, thermal, and catalytic functions in biomedicine. However, limited progress has been made to synthesize such porous metallic nanostructures with large mesopores (≥25 nm). Here, a green yet facile synthesis strategy using biocompatible liposomes as templates to mediate the formation of mesoporous metallic nanostructures in a controllable fashion is reported. Various monodispersed nanostructures with well-defined mesoporous shape and large mesopores (≈ 40 nm) are successfully synthesized from mono- (Au, Pd, and Pt), bi- (AuPd, AuPt, AuRh, PtRh, and PdPt), and tri-noble metals (AuPdRh, AuPtRh, and AuPdPt). Along with a successful demonstration of its effectiveness in synthesis of various mesoporous nanostructures, the possible mechanism of liposome-guided formation of such nanostructures via time sectioning of the synthesis process (monitoring time-resolved growth of mesoporous structures) and computational quantum molecular modeling (analyzing chemical interaction energy between metallic cations and liposomes at the enthalpy level) is also revealed. These mesoporous metallic nanostructures exhibit a strong photothermal effect in the near-infrared region, effective catalytic activities in hydrogen peroxide decomposition reaction, and high drug loading capacity. Thus, the liposome-templated method provides an inspiring and robust avenue to synthesize mesoporous noble metal-based nanostructures for versatile biomedical applications.
Asunto(s)
Liposomas , Nanoestructuras , Nanoestructuras/química , Metales/químicaRESUMEN
In search of effective therapeutics for breast cancers, establishing physiologically relevant in vitro models is of great benefit to facilitate the clinical translation. Despite extensive progresses, it remains to develop the tumor models maximally recapturing the key pathophysiological attributes of their native counterparts. Therefore, the current study aimed to develop a microsphere-enabled modular approach toward the formation of in vitro breast tumor models with the capability of incorporating various selected cells while retaining spatial organization. Poly (lactic-co-glycolic acid) microspheres (150-200 mm) with tailorable pore size and surface topography are fabricated and used as carriers to respectively lade with breast tumor-associated cells. Culture of cell-laden microspheres assembled within a customized microfluidic chamber allowed to form 3D tumor models with spatially controlled cell distribution. The introduction of endothelial cell-laden microspheres into cancer-cell laden microspheres at different ratios would induce angiogenesis within the culture to yield vascularized tumor. Evaluation of anticancer drugs such as doxorubicin and Cediranib on the tumor models do demonstrate corresponding physiological responses. Clearly, with the ability to modulate microsphere morphology, cell composition and spatial distribution, microsphere-enabled 3D tumor tissue formation offers a high flexibility to satisfy the needs for pathophysiological study, anticancer drug screening or design of personalized treatment.
RESUMEN
Flexible surface-enhanced Raman spectroscopy (SERS) substrate has attracted great attention due to its convenient sampling and on-site monitoring capability. However, it is still challenging to fabricate a versatile flexible SERS substrate, which can be used for in situ detection of analytes either in water or on irregular solid surfaces. Here, we report a flexible and transparent SERS substrate based on a wrinkled polydimethylsiloxane (PDMS) film obtained by transferring corrugated structures on the aluminium/polystyrene bilayer film, onto which silver nanoparticles (Ag NPs) are deposited by thermal evaporation. The as-fabricated SERS substrate exhibits a high enhancement factor (â¼1.19×105), good signal uniformity (RSD of 6.27%), and excellent batch-to-batch reproducibility (RSD of 7.3%) for rhodamine 6â G. In addition, the Ag NPs@W-PDMS film can maintain high detection sensitivity even after mechanical deformations of bending or torsion for 100 cycles. More importantly, being flexible, transparent, and light, the Ag NPs@W-PDMS film can both float on the water surface and conformally contact with the curved surface for in situ detection. The malachite green in aqueous environment and on apple peel can be easily detected down to 10-6 M with a portable Raman spectrometer. Therefore, it is expected that such a versatile flexible SERS substrate has great potential in on-site, in situ contaminant monitoring for realistic applications.
RESUMEN
Advanced multifunctional biomaterials are increasingly relying on clinically dictated patterns of selectivity against various biological targets. Integration of these frequently conflicting features into a single material surface may be best achieved by combining various complementary methodologies. Herein, a drug with a broad spectrum of activity, i.e., 4-methylumbelliferone (4-MU), is synthetically multimerized into water-soluble anionic macromolecules with the polyphosphazene backbone. The polymer structure, composition, and solution behavior are studied by 1H and 31P NMR spectroscopy, size-exclusion chromatography, dynamic light scattering, and UV and fluorescence spectrophotometry. To take advantage of the clinically proven hemocompatibility of fluorophosphazene surfaces, the drug-bearing macromolecule was then nanoassembled onto the surface of selected substrates in an aqueous solution with fluorinated polyphosphazene of the opposite charge using the layer-by-layer (LbL) technique. Nanostructured 4-MU-functionalized fluoro-coatings exhibited a strong antiproliferative effect on vascular smooth muscle cells (VSMCs) and fibroblasts with no cytotoxicity against endothelial cells. This selectivity pattern potentially provides the opportunity for highly desirable fast tissue healing while preventing the overgrowth of VSMCs and fibrosis. Taken together with the established in vitro hemocompatibility and anticoagulant activity, 4-MU-functionalized fluoro-coatings demonstrate potential for applications as restenosis-resistant coronary stents and artificial joints.
Asunto(s)
Células Endoteliales , Himecromona , Himecromona/farmacología , Propiedades de Superficie , Polímeros/farmacología , Materiales Biocompatibles Revestidos/químicaRESUMEN
Polyoxometalates (POMs), as a class of multinuclear metal oxygen clusters, have promising biological activities. And their amino acid derivatives will lead to better pharmacological activity by the diversity in structures and properties. With reference to the anti-HIV-1 activities of PM-19 (K7PTi2W10O40) and its pyridinium derivatives, a series of novel Keggin-type POMs with amino acid as organic cations (A7PTi2W10O40) were synthesized by hydrothermal synthetic method. The final products were characterized by 1H NMR, Elemental analyzes and single crystal X-ray diffraction. All the synthesized compounds were obtained in the yields of 44.3-61.7% and evaluated the cytotoxicity and anti-HIV-1 activity in vitro. Compared with the reference compound PM-19, the target compounds had a lower toxicity to TZM-bl cells and a higher inhibitory activity against HIV-1. Among them, compound A3 showed higher anti-HIV-1 activity with IC50 of 0.11 nM than that of PM-19 with 4.68 nM. This study demonstrated that combination of Keggin-type POMs and amino acids can be a new strategy to enhance the anti-HIV-1 biological activity of POMs. All results will be expected to helpful for developing more potent and effective HIV-1 inhibitors.
Asunto(s)
Aminoácidos , Aminoácidos/farmacología , Cristalografía por Rayos XRESUMEN
Circular RNAs (ciRNAs) are emerging as new players in the regulation of gene expression. However, how ciRNAs are involved in neuropathic pain is poorly understood. Here, we identify the nervous-tissue-specific ciRNA-Fmn1 and report that changes in ciRNA-Fmn1 expression in spinal cord dorsal horn neurons play a key role in neuropathic pain after nerve injury. ciRNA-Fmn1 was significantly downregulated in ipsilateral dorsal horn neurons after peripheral nerve injury, at least in part because of a decrease in DNA helicase 9 (DHX9), which regulates production of ciRNA-Fmn1 by binding to DNA-tandem repeats. Blocking ciRNA-Fmn1 downregulation reversed nerve-injury-induced reductions in both the binding of ciRNA-Fmn1 to the ubiquitin ligase UBR5 and the level of ubiquitination of albumin (ALB), thereby abrogating the nerve-injury-induced increase of ALB expression in the dorsal horn and attenuating the associated pain hypersensitivities. Conversely, mimicking downregulation of ciRNA-Fmn1 in naïve mice reduced the UBR5-controlled ubiquitination of ALB, leading to increased expression of ALB in the dorsal horn and induction of neuropathic-pain-like behaviors in naïve mice. Thus, ciRNA-Fmn1 downregulation caused by changes in binding of DHX9 to DNA-tandem repeats contributes to the genesis of neuropathic pain by negatively modulating UBR5-controlled ALB expression in the dorsal horn.
Asunto(s)
Neuralgia , ARN Circular , Ratones , Animales , ARN Circular/metabolismo , Regulación hacia Abajo , ADN Helicasas , Hiperalgesia/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Neuralgia/etiologíaRESUMEN
A quadriwave lateral shearing interferometry (QWLSI) is proposed based on double birefringent crystals of a beam displacer (DBCs-BD). The DBCs-BD is formed by adopting two birefringent crystals of a polarization beam displacer (PBD), which can generate the lateral shearing interference waves of four beams of overlapped replicas in the DBCs-BD orthogonal directions. When the replica waves are overlapped incident to the analyzer, and the direction of the transmission axis is set as 45° or 135°, the QWLSI's polarization interferogram can be obtained. The high-precision phase can be obtained by simple spectrum denoising and performing the Fourier transform of the resulting interferogram. We deduce the principle of QWLSI in detail, and the wavefront distribution can be achieved by the phase calculation. The experiment shows that the DBCs-BD-QWLSI exhibits feasibility and high precision.
RESUMEN
Cell encapsulation has been studied for various applications ranging from cell transplantation to biological production. However, current encapsulation technologies focus on cell protection rather than cell regulation that is essential to most if not all cell-based applications. Here we report a method for cell nanoencapsulation and regulation using an ultrathin biomimetic extracellular matrix as a cell nanocapsule to carry nanoparticles (CN2 ). This method allows high-capacity nanoparticle retention at the vicinity of cell surfaces. The encapsulated cells maintain high viability and normal metabolism. When gold nanoparticles (AuNPs) are used as a model to decorate the nanocapsule, light irradiation transiently increases the temperature, leading to the activation of the heat shock protein 70 (HSP70) promoter and the regulation of reporter gene expression. As the biomimetic nanocapsule can be decorated with any or multiple NPs, CN2 is a promising platform for advancing cell-based applications.