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1.
FASEB J ; 38(5): e23511, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38421303

RESUMEN

KDM4C is implicated in the regulation of cell proliferation, differentiation, and maintenance in various stem cell types. However, its function in neural stem cells (NSCs) remains poorly understood. Therefore, this study aims to investigate the role and regulatory mechanism of KDM4C in NSCs. Primary hippocampal NSCs were isolated from neonatal mice, and both in vivo and in vitro lentivirus-mediated overexpression of KDM4C were induced in these hippocampal NSCs. Staining results revealed a significant increase in BrdU- and Ki-67-positive cells, along with an elevated number of cells in S phases due to KDM4C overexpression. Subsequently, RNA-seq was employed to analyze gene expression changes following KDM4C upregulation. GO enrichment analysis, KEGG analysis, and GSEA highlighted KDM4C-regulated genes associated with development, cell cycle, and neurogenesis. Protein-protein interaction analysis uncovered that ApoE protein interacts with several genes (top 10 upregulated and downregulated) regulated by KDM4C. Notably, knocking down ApoE mitigated the proliferative effect induced by KDM4C overexpression in NSCs. Our study demonstrates that KDM4C overexpression significantly upregulates ApoE expression, ultimately promoting proliferation in mouse hippocampal NSCs. These findings provide valuable insights into the molecular mechanisms governing neurodevelopment, with potential implications for therapeutic strategies in neurological disorders.


Asunto(s)
Apolipoproteínas E , Células-Madre Neurales , Animales , Ratones , Ciclo Celular , Proliferación Celular , Hipocampo
2.
J Biol Chem ; 299(3): 102965, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36736424

RESUMEN

Connexin (Cx)-forming channels play essential roles in maintaining lens homeostasis and transparency. We showed here channel-independent roles of Cx50 in cell-cell adhesion and confirmed the second extracellular (E2) domain as a critical domain for cell adhesion function. We found that cell adhesion decreased in cells expressing chimeric Cx50 in which the E2 domain was swapped with the E2 domain of either Cx43 or Cx46. In contrast, adhesion increased in cells expressing chimeric Cx43 and Cx46 with the Cx50 (E2) domain. This function is Cx channel-independent and Cx50 E2 domain-dependent cell adhesion acting in both homotypic and heterotypic manners. In addition, we generated eight site mutations of unique residues between Cx50 and the other two lens Cxs and found that mutation of any one of the residues abolished the adhesive function. Moreover, expression of adhesive-impaired mutants decreased adhesion-related proteins, N-cadherin and ß-catenin. Expression of the adhesion-impaired Cx50W188P mutant in embryonic chick lens caused enlarged extracellular spaces, distorted fiber organization, delayed nuclear condensation, and cortical cataracts. In summary, the results from both in vitro and in vivo studies demonstrate the importance of the adhesive function of Cx50 in the lens.


Asunto(s)
Adhesión Celular , Conexinas , Cristalino , Moléculas de Adhesión Celular/metabolismo , Diferenciación Celular , Conexinas/metabolismo , Proteínas del Ojo/metabolismo , Uniones Comunicantes/metabolismo , Cristalino/metabolismo , Cadherinas/metabolismo
3.
J Cell Physiol ; 239(4): e31178, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38214211

RESUMEN

Glioblastoma stem cells (GSCs) exert a crucial influence on glioblastoma (GBM) development, progression, resistance to therapy, and recurrence, making them an attractive target for drug discovery. UTX, a histone H3K27 demethylase, participates in regulating multiple cancer types. However, its functional role in GSCs remains insufficiently explored. This study aims to investigate the role and regulatory mechanism of UTX on GSCs. Analysis of TCGA data revealed heightened UTX expression in glioma, inversely correlating with overall survival. Inhibiting UTX suppressed GBM cell growth and induced apoptosis. Subsequently, we cultured primary GSCs from three patients, observing that UTX inhibition suppressed cell proliferation and induced apoptosis. RNA-seq was performed to analyze the gene expression changes after silencing UTX in GSCs. The results indicated that UTX-mediated genes were strongly correlated with GBM progression and regulatory tumor microenvironment. The transwell co-cultured experiment showed that silencing UTX in the transwell chamber GSCs inhibited the well plate cell proliferation. Protein-protein interaction analysis revealed that periostin (POSTN) played a role in the UTX-mediated transcriptional regulatory network. Replenishing POSTN reversed the effects of UTX inhibition on GSC proliferation and apoptosis. Our study demonstrated that UTX inhibition hindered POSTN expression by enhancing the H3K27me2/3 level, eventually resulting in inhibiting proliferation and promoting apoptosis of patient-derived GSCs. Our findings may provide a novel and effective strategy for the treatment of GBM.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Histona Demetilasas , Células Madre Neoplásicas , Humanos , Apoptosis/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/genética , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/patología , Células Madre Neoplásicas/patología , Periostina , Microambiente Tumoral , Histona Demetilasas/antagonistas & inhibidores , Histona Demetilasas/metabolismo
4.
Small ; 20(27): e2310837, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38644345

RESUMEN

Gallium Nitride (GaN), as the representative of wide bandgap semiconductors, has great prospects in accomplishing rapid charge delivery under high-temperature environments thanks to excellent structural stability and electron mobility. However, there is still a gap in wafer-scale GaN single-crystal integrated electrodes applied in the energy storage field. Herein, Si-doped GaN nanochannel with gallium oxynitride (GaON) layer on a centimeter scale (denoted by GaN NC) is reported. The Si atoms modulate electronic redistribution to improve conductivity and drive nanochannel formation. Apart from that, the distinctive nanochannel configuration with a GaON layer provides adequate active sites and extraordinary structural stability. The GaN-based supercapacitors are assembled and deliver outstanding charge storage capabilities at 140 °C. Surprisingly, 90% retention is maintained after 50 000 cycles. This study opens the pathway toward wafer-scale GaN single-crystal integrated electrodes with self-powered characteristics that are compatible with various (opto)-electronic devices.

5.
Nat Immunol ; 13(5): 457-64, 2012 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-22447027

RESUMEN

To kill invading bacteria, neutrophils must interpret spatial cues, migrate and reach target sites. Although the initiation of chemotactic migration has been extensively studied, little is known about its termination. Here we found that two mitogen-activated protein kinases (MAPKs) had opposing roles in neutrophil trafficking. The extracellular signal-regulated kinase Erk potentiated activity of the G protein-coupled receptor kinase GRK2 and inhibited neutrophil migration, whereas the MAPK p38 acted as a noncanonical GRK that phosphorylated the formyl peptide receptor FPR1 and facilitated neutrophil migration by blocking GRK2 function. Therefore, the dynamic balance between Erk and p38 controlled neutrophil 'stop' and 'go' activity, which ensured that neutrophils reached their final destination as the first line of host defense.


Asunto(s)
Quimiotaxis de Leucocito , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Quinasa 2 del Receptor Acoplado a Proteína-G/metabolismo , Neutrófilos/inmunología , Receptores de Formil Péptido/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Flavonoides/farmacología , Células HEK293 , Células HL-60 , Humanos , Imidazoles/farmacología , Ratones , Ratones Noqueados , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
6.
Biomacromolecules ; 25(5): 3001-3010, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38598264

RESUMEN

Glycosylation is a valuable tool for modulating protein solubility; however, the lack of reliable research strategies has impeded efficient progress in understanding and applying this modification. This study aimed to bridge this gap by investigating the solubility of a model glycoprotein molecule, the carbohydrate-binding module (CBM), through a two-stage process. In the first stage, an approach involving chemical synthesis, comparative analysis, and molecular dynamics simulations of a library of glycoforms was employed to elucidate the effect of different glycosylation patterns on solubility and the key factors responsible for the effect. In the second stage, a predictive mathematical formula, innovatively harnessing machine learning algorithms, was derived to relate solubility to the identified key factors and accurately predict the solubility of the newly designed glycoforms. Demonstrating feasibility and effectiveness, this two-stage approach offers a valuable strategy for advancing glycosylation research, especially for the discovery of glycoforms with increased solubility.


Asunto(s)
Aprendizaje Automático , Simulación de Dinámica Molecular , Solubilidad , Glicosilación , Glicoproteínas/química
7.
Physiol Plant ; 176(4): e14421, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38956781

RESUMEN

The seasonal plasticity of resistance to xylem embolism has been demonstrated in leaves of some tree species, but is controversial in stems. In this study, we investigated the seasonality of stem xylem resistance to embolism in six temperate woody species (four deciduous and two evergreen tree species) that were grown at the same site. The xylem conduit anatomy, the concentrations, and ratios of the main cation in the xylem sap, as well as the content of nonstructural carbohydrates (including soluble sugars and starch) were measured in each species under each season to reveal the potential mechanisms of seasonal change in embolism resistance. The stem of all species showed increasing resistance to embolism as seasons progressed, with more vulnerable xylem in spring, but no significant adjustment in the other three seasons. The seasonal plasticity of stem embolism resistance was greater in deciduous species than in evergreen. On a seasonal scale, conduit diameter and conduit implosion resistance, the ratios of K+/Ca2+ and K+/Na+, and starch content were generally not correlated with embolism resistance, suggesting that these are probably not the main drivers of seasonal plasticity of stem embolism resistance. The seasonality of embolism resistance provides critical information for better understanding plant hydraulics in response to seasonal environments, especially under climate change.


Asunto(s)
Tallos de la Planta , Estaciones del Año , Árboles , Tallos de la Planta/fisiología , Árboles/fisiología , Xilema/fisiología
8.
Arch Toxicol ; 98(3): 897-909, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38172301

RESUMEN

Sulfur mustard (SM) is a highly toxic blister agent which has been used many times in several wars and conflicts and caused heavy casualties. Ease of production and lack of effective therapies make SM a potential threat to public health. SM intoxication causes severe damage on various target organs, such as the skin, eyes, and lungs. In addition, SM exposure can also lead to hepatotoxicity and severe liver injuries. However, despite decades of research, the molecular mechanism underlying SM-induced liver damage remains obscure. SM can be converted into various products via complex hepatic metabolism in vivo. There are some pieces of evidence that one of the oxidation products of SM, divinyl sulfone (DVS), exhibits even more significant toxicity than SM. Nevertheless, the molecular toxicology of DVS is still hardly known. In the present study, we confirmed that DVS is even more toxic than SM in the human hepatocellular carcinoma cell line HepG2. Further mechanistic study revealed that DVS exposure (200 µM) promotes pyroptosis in HepG2 cells, while SM (400 µM) mainly induces apoptosis. DVS induces gasdermin D (GSDMD) mediated pyroptosis, which is independent of caspases activation but depends on the large amounts of reactive oxygen species (ROS) and severe oxidative stress produced during DVS exposure. Our findings may provide novel insights for understanding the mechanism of SM poisoning and may be helpful to discover promising therapeutic strategies for SM intoxication.


Asunto(s)
Sustancias para la Guerra Química , Gas Mostaza , Sulfonas , Humanos , Gas Mostaza/toxicidad , Caspasas/metabolismo , Piroptosis , Hepatocitos , Estrés Oxidativo , Sustancias para la Guerra Química/metabolismo
9.
Artículo en Inglés | MEDLINE | ID: mdl-38427049

RESUMEN

PURPOSE: To investigate the characteristics and associations of anterior lens zonules lengths in cataract patients via ultrasound biomicroscope (UBM) measurement. METHODS: Patients with age-related cataracts and high myopic cataracts who planned to undergo cataract surgery were included in the study. After routine ophthalmic examinations, the UBM was performed on both eyes to get images of the anterior lens zonules, and Image J software was used to measure the lengths of the lens zonules. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT), and white-to-white (WTW) diameter of both eyes were obtained by IOL Master 700. Univariate and multivariate regression analyses were used to assess associated factors of anterior lens zonules lengths. RESULTS: Forty-nine patients with age-related cataracts and 33 patients with high myopic cataracts were enrolled. High myopic cataract patients were younger and had longer anterior lens zonules. Multivariate regression analysis showed that anterior lens zonules lengths were associated with axial lengths (temporal location: ß = 0.036, P = 0.029; nasal location: ß = 0.034, P = 0.011; superior location: ß = 0.046, P = 0.002) and ACD (inferior location: ß = 0.305, P = 0.016) in right eyes. In left eyes, anterior lens zonules lengths were associated with axial lengths (temporal location: ß = 0.028, P = 0.017; inferior location: ß = 0.026, P = 0.016; nasal location: ß = 0.033, P < 0.001) and ACD (inferior location: ß = 0.215, P = 0.030; superior location: ß = 0.290, P = 0.011). CONCLUSIONS: High myopic cataract patients have longer anterior lens zonules. AL and ACD contributed to the lengths of anterior lens zonules. Thus, for patients with long AL and deeper ACD, lens zonules measurement was crucial. CLINICAL TRIAL REGISTRATION: www.chictr.org.cn identifier is ChiCTR2300071397.

10.
J Asian Nat Prod Res ; 26(3): 342-352, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37933140

RESUMEN

Bicyclol, an innovative hepatoprotective drug, was approved by the Chinese National Medical Products Administration (NMPA) in 2001 to treat Hepatitis B and drug-induced liver injury. Two active metabolites of bicyclol have been identified as M2 and M3. To evaluate the impact on drug safety and efficacy of possible drug-drug interactions (DDIs) associated with these metabolites, a sufficient quantity of these metabolites is required. Herein, we report a concise novel route for the synthesis of M2 and M3 using the Suzuki-Miyaura coupling as the key step. Furthermore, we complete the gram-scale syntheses of M2 and M3.


Asunto(s)
Compuestos de Bifenilo , Enfermedad Hepática Inducida por Sustancias y Drogas , Compuestos de Bifenilo/farmacología , Sustancias Protectoras , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico
11.
J Environ Manage ; 359: 121003, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692032

RESUMEN

Globally, most high-grade ores have already been exploited. Contemporary mining tends to focus on the extraction of lower-grade ores thereby leaving large stored tailings open to the environment. As a result, current mines have emerged as hotspots for the migration of metal(loid)s and resistance genes, thereby potentially contributing to a looming public health crisis. Therefore, the management and remediation of tailings are the most challenging issues in environmental ecology. Bioremediation, a cost-effective solution for the treatment of multi-element mixed pollution (co-contamination), shows promise for the restoration of mine tailings. This review focuses on the bioremediation technologies developed to untangle the issues of non-ferrous metal mine tailings. These technologies address the environmental risks of multi-element exposure to the ecosystem and human health risks. It provides a review and comparison of current bioremediation technologies used to mineralize metal(loid)s. The role of plant-microorganisms and their mechanisms in the remediation of tailings are also discussed. The importance of "treating waste with wastes" is crucial for advancing bioremediation technologies. This approach underscores the potential for waste materials to contribute to environmental cleanup processes. The concept of a circular economy is pertinent in this context, emphasizing recycling and reuse. There's an immediate need for international collaboration. Collaboration is needed in policy-making, funding, and data accessibility. Sharing data is essential for the growth of bioremediation globally.


Asunto(s)
Biodegradación Ambiental , Metales , Minería , Humanos , Reciclaje
12.
J Environ Manage ; 353: 120167, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38308995

RESUMEN

The quality of soil containing heavy metals (HMs) around nonferrous metal mining areas is often not favorable for plant growth. Three types of plant growth promoting rhizobacteria (PGPR)-assisted ryegrass were examined here to treat Cd, Pb, and Zn contaminated soil collected from a nonferrous metal smelting facility. The effects of PGPR-assisted plants on soil quality, plant growth, and the migration and transformation of HMs were evaluated. Results showed that inter-root inoculation of PGPR to ryegrass increased soil redox potential, urease, sucrase and acid phosphatase activities, microbial calorimetry, and bioavailable P, Si, and K content. Inoculation with PGPR also increased aboveground parts and root length, P, Si, and K contents, and antioxidant enzyme activities. The most significant effect was that the simultaneous inoculation of all three PGPRs increased the ryegrass extraction (%) of Cd (59.04-79.02), Pb (105.56-157.13), and Zn (27.71-40.79), compared to CK control (without fungi). Correspondingly, the inter-root soil contents (%) of total Cd (39.94-57.52), Pb (37.59-42.17), and Zn (34.05-37.28) were decreased compared to the CK1 control (without fungi and plants), whereas their bioavailability was increased. Results suggest that PGPR can improve soil quality in mining areas, promote plant growth, transform the fraction of HMs in soil, and increase the extraction of Cd, Pb, and Zn by ryegrass. PGPR is a promising microbe-assisted phytoremediation strategy that can promote the re-greening of vegetation in the mining area while remediating HMs pollution.


Asunto(s)
Lolium , Metales Pesados , Contaminantes del Suelo , Cadmio , Plomo , Simbiosis , Suelo/química , Metales Pesados/análisis , Bacterias , Biodegradación Ambiental , Zinc , Contaminantes del Suelo/análisis
13.
Angew Chem Int Ed Engl ; 63(21): e202400769, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38544401

RESUMEN

Generating circularly polarized luminescence (CPL) with simultaneous high photoluminescence quantum yield (PLQY) and dissymmetry factor (glum) is difficult due to usually unmatched electric transition dipole moment (µ) and magnetic transition dipole moment (m) of materials. Herein we tackle this issue by playing a "cascade cationic insertion" trick to achieve strong CPL (with PLQY of ~100 %) in lead-free metal halides with high glum values reaching -2.3×10-2 without using any chiral inducers. Achiral solvents of hydrochloric acid (HCl) and N, N-dimethylformamide (DMF) infiltrate the crystal lattice via asymmetric hydrogen bonding, distorting the perovskite structure to induce the "intrinsic" chirality. Surprisingly, additional insertion of Cs+ cation to substitute partial (CH3)2NH2 + transforms the chiral space group to achiral but the crystal maintains chiroptical activity. Further doping of Sb3+ stimulates strong photoluminescence as a result of self-trapped excitons (STEs) formation without disturbing the crystal framework. The chiral perovskites of indium-antimony chlorides embedded on LEDs chips demonstrate promising potential as CPL emitters. Our work presents rare cases of chiroptical activity of highly luminescent perovskites from only achiral building blocks via spontaneous resolution as a result of symmetry breaking.

14.
Mol Med ; 29(1): 49, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-37020186

RESUMEN

BACKGROUND: The cytoskeletal architecture of osteoclasts (OCs) and bone resorption activity must be appropriately controlled for proper bone remodeling, which is associated with osteoporosis. The RhoA protein of GTPase plays a regulatory role in cytoskeletal components and contributes to osteoclast adhesion, podosome positioning, and differentiation. Although osteoclast investigations have traditionally been performed by in vitro analysis, however, the results have been inconsistent, and the significance of RhoA in bone physiology and pathology is still unknown. METHODS: We generated RhoA knockout mice by specifically deleting RhoA in the osteoclast lineage to understand more about RhoA's involvement in bone remodeling. The function of RhoA in osteoclast differentiation and bone resorption and the mechanisms were assessed using bone marrow macrophages (BMMs) in vitro. The ovariectomized (OVX) mouse model was adopted to examine the pathological effect of RhoA in bone loss. RESULTS: Conditional deletion of RhoA in the osteoclast lineage causes a severe osteopetrosis phenotype, which is attributable to a bone resorption suppression. Further mechanistic studies suggest that RhoA deficiency suppresses Akt-mTOR-NFATc1 signaling during osteoclast differentiation. Additionally, RhoA activation is consistently related to the significant enhancement the osteoclast activity, which culminates in the development of an osteoporotic bone phenotype. Furthermore, in mice, the absence of RhoA in osteoclast precursors prevented occurring OVX-induced bone loss. CONCLUSION: RhoA promoted osteoclast development via the Akt-mTOR-NFATc1 signaling pathway, resulting a osteoporosis phenotype, and that manipulating RhoA activity might be a therapeutic strategy for osteoporotic bone loss.


Asunto(s)
Resorción Ósea , Osteoporosis , Animales , Ratones , Resorción Ósea/complicaciones , Resorción Ósea/patología , Diferenciación Celular , Factores de Transcripción NFATC/metabolismo , Osteogénesis , Osteoporosis/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
15.
Mol Med ; 29(1): 165, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049769

RESUMEN

BACKGROUND: Disruption of the BBB is a harmful event after intracranial hemorrhage (ICH), and this disruption contributes to a series of secondary injuries. We hypothesized that FGF21 may have protective effects after intracranial hemorrhage (ICH) and investigated possible underlying molecular mechanisms. METHODS: Blood samples of ICH patients were collected to determine the relationship between the serum level of FGF21 and the [Formula: see text]GCS%. Wild-type mice, SIRT6flox/flox mice, endothelial-specific SIRT6-homozygous-knockout mice (eSIRT6-/- mice) and cultured human brain microvascular endothelial cells (HCMECs) were used to determine the protective effects of FGF21 on the BBB. RESULTS: We obtained original clinical evidence from patient data identifying a positive correlation between the serum level of FGF21 and [Formula: see text]GCS%. In mice, we found that FGF21 treatment is capable of alleviating BBB damage, mitigating brain edema, reducing lesion volume and improving neurofunction after ICH. In vitro, after oxyhemoglobin injury, we further explored the protective effects of FGF21 on endothelial cells (ECs), which are a significant component of the BBB. Mitochondria play crucial roles during various types of stress reactions. FGF21 significantly improved mitochondrial biology and function in ECs, as evidenced by alleviated mitochondrial morphology damage, reduced ROS accumulation, and restored ATP production. Moreover, we found that the crucial regulatory mitochondrial factor deacylase sirtuin 6 (SIRT6) played an irreplaceable role in the effects of FGF21. Using endothelial-specific SIRT6-knockout mice, we found that SIRT6 deficiency largely diminished these neuroprotective effects of FGF21. Then, we revealed that FGF21 might promote the expression of SIRT6 via the AMPK-Foxo3a pathway. CONCLUSIONS: We provide the first evidence that FGF21 is capable of protecting the BBB after ICH by improving SIRT6-mediated mitochondrial homeostasis.


Asunto(s)
Células Endoteliales , Sirtuinas , Humanos , Ratones , Animales , Células Endoteliales/metabolismo , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/tratamiento farmacológico , Hemorragia Cerebral/patología , Hemorragias Intracraneales/complicaciones , Hemorragias Intracraneales/patología , Ratones Noqueados , Sirtuinas/genética , Sirtuinas/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología
16.
Anal Chem ; 95(16): 6672-6680, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37053544

RESUMEN

Droplet microfluidics provides powerful tools for biochemical applications. However, precise fluid control is usually required in the process of droplet generation and detection, which hinders droplet-based applications in point-of-care testing (POCT). Here, we present a droplet reinjection method capable of droplet distribution without precise fluid control and external pumps by which the droplets can be passively aligned and detected one by one at intervals. By further integrating the surface-wetting-based droplet generation chip, an integrated POrtable Droplet system (iPODs) is developed. The iPODs integrates multiple functions such as droplet generation, online reaction, and serial reading. Using the iPODs, monodisperse droplets can be generated at a flow rate of 800 Hz with a narrow size distribution (CV <2.2%). Droplets are kept stable, and the fluorescence signal can be significantly identified after the reaction. The spaced droplet efficiency in the reinjection chip is nearly 100%. In addition, we validate digital loop-mediated isothermal amplification (dLAMP) within 80 min with a simple operation workflow. The results show that iPODs has good linearity (R2 = 0.999) at concentrations ranging from 101 to 104 copies/µL. Thus, the developed iPODs highlights its potential to be a portable, low-cost, and easy-to-deploy toolbox for droplet-based applications.

17.
Anal Chem ; 95(38): 14375-14383, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37710979

RESUMEN

Rapid and accurate antimicrobial prescriptions are critical for bloodstream infection (BSI) patients, as they can guide drug use and decrease mortality significantly. The traditional antimicrobial susceptibility testing (AST) for BSI is time-consuming and tedious, taking 2-3 days. Avoiding lengthy monoclonal cultures and shortening the drug sensitivity incubation time are keys to accelerating the AST. Here, we introduced a bacteria separation integrated AST (BSI-AST) chip, which could extract bacteria directly from positive blood cultures (PBCs) within 10 min and quickly give susceptibility information within 3 h. The integrated chip includes a bacteria separation chamber, multiple AST chambers, and connection channels. The separator gel was first preloaded into the bacteria separation chamber, enabling the swift separation of bacteria cells from PBCs through on-chip centrifugation. Then, the bacteria suspension was distributed in the AST chambers with preloaded antibiotics through a quick vacuum-assisted aliquoting strategy. Through centrifuge-assisted on-chip enrichment, detectable growth of the phenotype under different antibiotics could be easily observed in the taper tips of AST chambers within a few hours. As a proof of concept, direct AST from artificial PBCs with Escherichia coli against 18 antibiotics was performed on the BSI-AST chip, and the whole process from bacteria extraction to AST result output was less than 3.5 h. Moreover, the integrated chip was successfully applied to the diagnosis of clinical PBCs, showing 93.3% categorical agreement with clinical standard methods. The reliable and fast pathogen characterization of the integrated chip suggested its great potential application in clinical diagnosis.


Asunto(s)
Cultivo de Sangre , Sepsis , Humanos , Microfluídica , Antibacterianos/farmacología , Centrifugación , Escherichia coli
18.
Biochem Biophys Res Commun ; 665: 178-186, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37163938

RESUMEN

Cisplatin resistance is the main cause of postoperative recurrence and difficulty in the treatment of ovarian cancer. It is urgently needed to identify therapeutic drugs with unique functions to overcome the current challenges in the treatment of ovarian cancer. In this study, we found that TG promoted the accumulation of ROS and MDA in A2780/DDP cells and downregulated the expression of key antioxidant molecules. In vivo, the survival rate of tumor-bearing nude mice was prolonged by TG without significant hepatotoxic reaction. The expression of key antioxidant molecules in tumor tissues was consistent with that in vitro. These findings revealed that TG disrupted homeostasis of redox reactions and induced ferroptosis in A2780/DDP cells, thereby enhancing cisplatin chemosensitivity of ovarian cancer. Overall, TG may be a novel potential therapeutic option for reversing resistance to cisplatin chemotherapy.


Asunto(s)
Antineoplásicos , Ferroptosis , Neoplasias Ováricas , Animales , Ratones , Humanos , Femenino , Cisplatino/farmacología , Cisplatino/uso terapéutico , Neoplasias Ováricas/patología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Factor 2 Relacionado con NF-E2/metabolismo , Tripterygium , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Línea Celular Tumoral , Ratones Desnudos , Antioxidantes/farmacología , Resistencia a Antineoplásicos
19.
Small ; 19(50): e2303932, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37612814

RESUMEN

The slow charge transfer and high energy barrier are the key restrictions of cost-effective electrocatalysts for hydrogen production. A hierarchical heterostructure of MoN@NiFe-layered double hydroxides (LDH) is developed, with NiFe-LDH nanosheets supported on MoN nanowire arrays. The as-prepared MoN@NiFe-LDH exhibits a remarkably high performance on hydrogen production in alkaline medium, which is close to the benchmark Pt/C. The theoretical computations indicate that MoN@NiFe-LDH has a metallic character inherited from MoN, which gives rise to the promoted charge transfer. Furthermore, the adsorption intensity of intermediates on MoN@NiFe-LDH is optimized and thereby the energy barrier is diminished. This work demonstrates the significance of constructing heterostructure for boosting the charge transfer and reducing the energy barrier, which can shed light on the development of highly efficient and low-cost electrocatalyst for hydrogen production.

20.
Small ; 19(49): e2303608, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37587787

RESUMEN

Topological insulators (TIs) are characterized by a full insulating gap in the bulk and gapless edge or surface states, which have attracted tremendous attention. 2D Bi (110), as a typical TI, is of particular interest due to its low symmetry structure and topologically protected and spin-momentum-locked Dirac surface states. However, the material's potential applications are hindered by difficulties in fabrication, due to its strong semi-metallic bonding and poor stability. In this study, a novel electrochemical intercalation method for the fabrication of ultrathin Bi (110) nanosheets with the highest yield ever reported is presented. These nanosheets are stabilized through cathodic exfoliation in a reductive environment and further modification with polymer ionic liquids. The versatility of these nanosheets is demonstrated by fabricating flexible acoustic sensors with ultrahigh sensitivity. These sensors can even detect sounds as quiet as 45 dB. Furthermore, these sensors are utilized for acoustic-to-electric energy conversion and information transfer. This work offers a promising approach for scalable fabrication and preservation of ultrathin 2D TI Bi (110) nanosheets and paves the way for their integration into smart devices.

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