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1.
ACS Appl Mater Interfaces ; 16(11): 13422-13438, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38442213

RESUMEN

Current treatment for chronic infectious wounds is limited due to severe drug resistance in certain bacteria. Therefore, the development of new composite hydrogels with nonantibiotic antibacterial and pro-wound repair is important. Here, we present a photothermal antibacterial composite hydrogel fabricated with a coating of Fe2+ cross-linked carboxymethyl chitosan (FeCMCS) following the incorporation of melanin nanoparticles (MNPs) and the CyRL-QN15 peptide. Various physical and photothermal properties of the hydrogel were characterized. Cell proliferation, migration, cycle, and free-radical scavenging activity were assessed, and the antimicrobial properties of the hydrogel were probed by photothermal therapy. The effects of the hydrogel were validated in a model of methicillin-resistant Staphylococcus aureus (MRSA) infection with full-thickness injury. This effect was further confirmed by changes in cytokines associated with inflammation, re-epithelialization, and angiogenesis on the seventh day after wound formation. The MNPs demonstrated robust photothermal conversion capabilities. The composite hydrogel (MNPs/CyRL-QN15/FeCMCS) promoted keratinocyte and fibroblast proliferation and migration while exhibiting high antibacterial efficacy, effectively killing more than 95% of Gram-positive and Gram-negative bacteria. In vivo study using an MRSA-infected full-thickness injury model demonstrated good therapeutic efficacy of the hydrogel in promoting regeneration and remodeling of chronically infected wounds by alleviating inflammatory response and accelerating re-epithelialization and collagen deposition. The MNPs/CyRL-QN15/FeCMCS hydrogel showed excellent antibacterial and prohealing effects on infected wounds, indicating potential as a promising candidate for wound healing promotion.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Antibacterianos/farmacología , Hidrogeles/farmacología , Bacterias Gramnegativas , Bacterias Grampositivas , Melaninas , Péptidos
2.
Surg Endosc ; 38(4): 2050-2061, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38429573

RESUMEN

BACKGROUND: Choledochoscopy is a highly effective approach for managing intrahepatic bile duct stones (IHDs). However, postoperative infection is a common complication that significantly impacts treatment outcomes. Despite its clinical relevance, the risk factors associated with this procedure remain largely unexplored. METHODS: This study focused on a consecutive cohort of patients who underwent choledochoscopy for IHDs at our institution between January 2016 and December 2022. The primary objective was to analyze the relationship between various clinical factors and postoperative infection, and to compare the postoperative infection of different choledochoscopic procedures. RESULTS: The study cohort consisted of 126 patients, with 60 individuals (47.6%) experiencing postoperative infection. Notably, preoperative biliary obstruction (odds ratio [OR] 1.861; 95% confidence interval [CI] 1.314-8.699; p = 0.010) and operation time (OR 4.414; 95% CI 1.635-12.376; p = 0.004) were identified as risk factors for postoperative infection. Additionally, biliary tract infections (60.00%) were primarily responsible for postoperative infection, with Escherichia coli (47.22%) being the predominant bacterial strain identified in bile cultures. Furthermore, biliary tract obstruction (OR 4.563; 95% CI 1.554-13.401; p = 0.006) and body mass index (BMI) (OR 1.186; 95% CI 1.015-1.386; p = 0.031) were determined to be independent risk factors for postoperative biliary tract infection. CONCLUSIONS: The occurrence of postoperative infection in patients undergoing choledochoscopy was primarily associated with the duration of the operation and the presence of preoperative biliary obstruction.


Asunto(s)
Colestasis , Laparoscopía , Humanos , Estudios Retrospectivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Conductos Biliares Intrahepáticos , Factores de Riesgo
3.
Small ; : e2309894, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308168

RESUMEN

Real-time biodistribution monitoring and enhancing the therapeutic efficacy of platinum(II)-based anticancer drugs are urgently required to elevate their clinical performance. Herein, a tetraphenylethene derivative (TP) with aggregation-induced emission (AIE) properties and an iodine atom are selected as ligands to endow platinum (II) complex TP-Pt-I with real-time in vivo self-tracking ability by fluorescence (FL) and computerized tomography (CT) imaging, and improved anticancer efficacy by the combination of chemotherapy and photodynamic therapy. Especially, benefiting from the formation of a donor-acceptor-donor structure between the AIE photosensitizer TP and Pt-I moiety, the heavy atom effects of Pt and I, and the presence of I, TP-Pt-I displayed red-shifted absorption and emission wavelengths, enhanced ROS generation efficiency, and improved CT imaging capacity compared with the pristine TP and the control agent TP-Pt-Cl. As a result, the enhanced intratumoral accumulation of TP-Pt-I loaded nanoparticles is readily revealed by dual-modal FL and CT imaging with high contrast. Meanwhile, the TP-Pt-I nanoparticles show significantly improved tumor growth-inhibiting effects on an MCF-7 xenograft murine model by combining the chemotherapeutic effects of platinum(II) and the photodynamic effects of TP. This self-tracking therapeutic complex thus provides a new strategy for improving the therapeutic outcomes of platinum(II)-based anticancer drugs.

4.
Cancers (Basel) ; 16(2)2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38254761

RESUMEN

BACKGROUND: tumor-associated macrophages (TAMs) constitute a significant proportion of non-cancerous cells within the intricate tumor microenvironment (TME) of hepatocellular carcinoma (HCC). Understanding the communication between macrophages and tumor cells, as well as investigating potential signaling pathways, holds promise for enhancing therapeutic responses in HCC. METHODS: single-cell RNA-sequencing data and bulk RNA-sequencing data were derived from open source databases Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Through this analysis, we elucidated the interactions between MICA+ tumor cells and MMP9+ macrophages, primarily mediated via the PROS1-AXL axis in advanced HCC. Subsequently, we employed a range of experimental techniques including lentivirus infection, recombinant protein stimulation, and AXL inhibition experiments to validate these interactions and unravel the underlying mechanisms. RESULTS: we presented a single-cell atlas of advanced HCC, highlighting the expression patterns of MICA and MMP9 in tumor cells and macrophages, respectively. Activation of the interferon gamma (IFN-γ) signaling pathway was observed in MICA+ tumor cells and MMP9+ macrophages. We identified the existence of an interaction between MICA+ tumor cells and MMP9+ macrophages mediated via the PROS1-AXL axis. Additionally, we found MMP9+ macrophages had a positive correlation with M2-like macrophages. Subsequently, experiments validated that DNA damage not only induced MICA expression in tumor cells via IRF1, but also upregulated PROS1 levels in HCC cells, stimulating macrophages to secrete MMP9. Consequently, MMP9 led to the proteolysis of MICA. CONCLUSION: MICA+ HCC cells secreted PROS1, which upregulated MMP9 expression in macrophages through AXL receptors. The increased MMP9 activity resulted in the proteolytic shedding of MICA, leading to the release of soluble MICA (sMICA) and the subsequent facilitation of tumor immune escape.

6.
J Laparoendosc Adv Surg Tech A ; 33(11): 1088-1096, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37751197

RESUMEN

Background: Laparoscopic liver resection (LLR) has become a widely used standardized operation for patients with hepatocellular carcinoma (HCC) in the field of hepatic surgery. However, the risk factors and long-term implications associated with unplanned conversion to an open procedure during the LLR have not been adequately studied. Methods: The study incorporated 96 patients with HCC. Risk factors of conversion and their prognosis were analyzed by comparing patients who successfully underwent LLR with those who required unplanned conversion. Results: In this study, the unplanned conversion rate for laparoscopic hepatectomy was 42.7%. Patients who underwent conversion had longer length of stay (8 versus 7 days, P < .001), longer operation time (297.73 versus 194.03 minutes, P = .000), a higher transfusion rate (29.3% versus 5.5%, P < .001), and more postoperative complications compared with patients who successfully underwent LLR. The two surgical maneuvers did not show substantial disparities in terms of total survival and disease-free survival rates. Risk factors of unplanned conversion contained tumor location (odds ratio [OR], 3.129; 95% confidence interval [CI]: 1.214-8.066; P = 0.018) and tumor size (OR, 2.652; 95% CI: 1.039-6.767; P = 0.041). Conclusions: The unplanned conversion during LLR for HCC was linked to unfavorable short-term prognosis, yet it did not influence long-term oncologic outcomes. Moreover, preoperative evaluation of tumor size and location may effectively reduce the probability of unplanned conversion during LLR.


Asunto(s)
Carcinoma Hepatocelular , Laparoscopía , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Neoplasias Hepáticas/cirugía , Estudios Retrospectivos , Factores de Riesgo , Complicaciones Posoperatorias/etiología , Laparoscopía/métodos , Tiempo de Internación
7.
Nat Aging ; 3(10): 1288-1311, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37697166

RESUMEN

As important immune cells, microglia undergo a series of alterations during aging that increase the susceptibility to brain dysfunctions. However, the longitudinal characteristics of microglia remain poorly understood. In this study, we mapped the transcriptional and epigenetic profiles of microglia from 3- to 24-month-old mice. We first discovered unexpected sex differences and identified age-dependent microglia (ADEM) genes during the aging process. We then compared the features of aging and reactivity in female microglia at single-cell resolution and epigenetic level. To dissect functions of aged microglia excluding the influence from other aged brain cells, we established an accelerated microglial turnover model without directly affecting other brain cells. By this model, we achieved aged-like microglia in non-aged brains and confirmed that aged-like microglia per se contribute to cognitive decline. Collectively, our work provides a comprehensive resource for decoding the aging process of microglia, shedding light on how microglia maintain brain functions.


Asunto(s)
Disfunción Cognitiva , Microglía , Femenino , Ratones , Masculino , Animales , Encéfalo , Envejecimiento/genética , Disfunción Cognitiva/genética , Epigénesis Genética
8.
Opt Express ; 31(8): 12232-12248, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157387

RESUMEN

This paper presents a maskless lithography system that can perform three-dimensional (3D) ultraviolet (UV) patterning on a photoresist (PR) layer. After PR developing processes, patterned 3D PR microstructures over a large area are obtained. This maskless lithography system utilizes an UV light source, a digital micromirror device (DMD), and an image projection lens to project a digital UV image on the PR layer. The projected UV image is then mechanically scanned over the PR layer. An UV patterning scheme based on the idea of obliquely scanning and step strobe lighting (OS3L) is developed to precisely control the spatial distribution of projected UV dose, such that desired 3D PR microstructures can be obtained after PR development. Two types of concave microstructures with truncated conical and nuzzle-shaped cross-sectional profiles are experimentally obtained over a patterning area of 160 ×115 mm2. These patterned microstructures are then used for replicating nickel molds and for mass-production of light-guiding plates used in back-lighting and display industry. Potential improvements and advancements of the proposed 3D maskless lithography technique for future applications will be addressed.

9.
Adv Healthc Mater ; 12(23): e2300375, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37141030

RESUMEN

Diabetic foot ulcer (DFU), a common complication of diabetes, has become a great burden to both patients and the society. The delayed wound closure of ulcer sites resulting from vascular damage and neutrophil dysfunction facilitates bacterial infection. Once drug resistance occurs or bacterial biofilm is formed, conventional therapy tends to fail and amputation is unavoidable. Therefore, effective antibacterial treatment beyond antibiotics is of utmost importance to accelerate the wound healing process and prevent amputation. Considering the complexity of multidrug resistance, biofilm formation, and special microenvironments (such as hyperglycemia, hypoxia, and abnormal pH value) at the infected site of DFU, several antibacterial agents and different mechanisms have been explored to achieve the desired outcome. The present review focuses on the recent progress of antibacterial treatments, including metal-based medications, natural and synthesized antimicrobial peptides, antibacterial polymers, and sensitizer-based therapy. This review provides a valuable reference for the innovation of antibacterial material design for DFU therapy.


Asunto(s)
Infecciones Bacterianas , Diabetes Mellitus , Pie Diabético , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pie Diabético/tratamiento farmacológico , Pie Diabético/complicaciones , Diabetes Mellitus/tratamiento farmacológico , Cicatrización de Heridas , Infecciones Bacterianas/tratamiento farmacológico , Resultado del Tratamiento
10.
Adv Healthc Mater ; 12(22): e2300253, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37097737

RESUMEN

Platinum drugs with manifest therapeutic effects are widely used, but their systemic toxicity and the drug resistance acquired by cancer cells limit their clinical applications. Thus, the exploration on appropriate methods and strategies to overcome the limitations of traditional platinum drugs becomes extremely necessary. Combination therapy of platinum drugs can inhibit tumor growth and metastasis in an additive or synergistic manner, and can potentially reduce the systemic toxicity of platinum drugs and overcome platinum-resistance. This review summarizes the various modalities and current progress in platinum-based combination therapy. The synthetic strategies and therapeutic effects of some platinum-based anticancer complexes in the combination of platinum drugs with gene editing, ROS-based therapy, thermal therapy, immunotherapy, biological modelling, photoactivation, supramolecular self-assembly and imaging modality are briefly described. Their potential challenges and prospects are also discussed. It is hoped that this review will inspire researchers to have more ideas for the future development of highly effective platinum-based anti-cancer complexes.


Asunto(s)
Antiinfecciosos , Antineoplásicos , Neoplasias , Humanos , Platino (Metal)/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Terapia Combinada , Penicilinas/uso terapéutico , Antiinfecciosos/uso terapéutico
11.
J Laparoendosc Adv Surg Tech A ; 33(7): 615-621, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36862541

RESUMEN

Background: The difficulty scoring system based on the extent of resection (DSS-ER) is a common tool for assessing the difficulty and risk of laparoscopic liver resection (LLR), but DSS-ER fails to comprehensively and accurately assess low level for beginners. Methods: The 93 cases of LLRs for primary liver cancer in the general surgery department of the Second Affiliated Hospital of Guangxi Medical University from 2017 to 2021 were retrospectively analyzed. The low level of DSS-ER difficulty scoring system was reclassified into three grades. The intraoperative and postoperative complications were compared among different groups. Results: There were significant differences in the operative time, blood loss, intraoperative allogeneic blood transfusion, conversion to laparotomy, and allogeneic blood transfusion among the different groups. Meanwhile, the postoperative complications were mainly pleural effusion and pneumonia, and the incidence of grade III was higher compared with other two grades. No significant difference existed in the postoperative biliary leakage and liver failure among three grades. Conclusions: This reclassified low level of DSS-ER difficulty scoring system has certain clinical value for LLR beginners to complete the corresponding learning curve.


Asunto(s)
Carcinoma Hepatocelular , Laparoscopía , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/complicaciones , Estudios Retrospectivos , China , Hepatectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Laparoscopía/efectos adversos , Tiempo de Internación , Carcinoma Hepatocelular/cirugía
12.
Stem Cells Int ; 2023: 7074703, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36845966

RESUMEN

Ginsenoside Rg1 (Rg1) is purified from ginseng with various pharmacological effects, which might facilitate the biological behavior of human amnion-derived mesenchymal stem/stromal cells (hAD-MSCs). This study is aimed at investigating the effects of Rg1 on the biological behavior, such as viability, proliferation, apoptosis, senescence, migration, and paracrine, of hAD-MSCs. hAD-MSCs were isolated from human amnions. The effects of Rg1 on the viability, proliferation, apoptosis, senescence, migration, and paracrine of hAD-MSCs were detected by CCK-8, EdU, flow cytometry, SA-ß-Gal staining, wound healing, and ELISA assays, respectively. The protein expression levels were detected by western blot. Cell cycle distribution was evaluated using flow cytometry. We found that Rg1 promoted hAD-MSC cycle progression from G0/G1 to S and G2/M phases and significantly increased hAD-MSC proliferation rate. Rg1 activated PI3K/AKT signaling pathway and significantly upregulated the expressions of cyclin D, cyclin E, CDK4, and CDK2 in hAD-MSCs. Inhibition of PI3K/AKT signaling significantly downregulated the expressions of cyclin D, cyclin E, CDK4, and CDK2, prevented cell cycle progression, and reduced hAD-MSC proliferation induced by Rg1. hAD-MSC senescence rate was significantly increased by D-galactose, while the elevated hAD-MSC senescence rate induced by D-galactose was significantly decreased by Rg1 treatment. D-galactose significantly induced the expressions of senescence markers, p16INK4a, p14ARF, p21CIP1, and p53 in hAD-MSCs, while Rg1 significantly reduced the expressions of those markers induced by D-galactose in hAD-MSCs. Rg1 significantly promoted the secretion of IGF-I in hAD-MSCs. Rg1 reduced the hAD-MSC apoptosis rate. However, the difference was not significant. Rg1 had no influence on hAD-MSC migration. Altogether, our results demonstrate that Rg1 can promote the viability, proliferation, and paracrine and relieve the senescence of hAD-MSCs. PI3K/AKT signaling pathway is involved in the promotive effect of Rg1 on hAD-MSC proliferation. The protective effect of Rg1 on hAD-MSC senescence may be achieved via the downregulation of p16INK4A and p53/p21CIP1 pathway.

13.
Cancers (Basel) ; 15(3)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36765808

RESUMEN

BACKGROUND: CHK1 is considered a key cell cycle checkpoint kinase in DNA damage response (DDR) pathway to communicate with several signaling pathways involved in the tumor microenvironment (TME) in numerous cancers. However, the mechanism of CHK1 signaling regulating TME in hepatocellular carcinoma (HCC) remains unclear. METHODS: CHK1 expression in HCC tissue was determined by IHC staining assay. DNA damage and apoptosis in HCC cells induced by cisplatin or CHK1 inhibition were detected by WB and flow cytometry. The interaction of CHK1 and IRF1 was analyzed by single-cell RNA-sequence, WB, and immunoprecipitation assay. The mechanism of IRF1 regulating MICA was investigated by ChIP-qPCR. RESULTS: CHK1 expression is upregulated in human HCC tumors compared to the background liver. High CHK1 mRNA level predicts advanced tumor stage and worse prognosis. Cisplatin and CHK1 inhibition augment cellular DNA damage and apoptosis. Overexpressed CHK1 suppresses IRF1 expression through proteolysis. Furthermore, single-cell RNA-sequence analyses confirmed that MICA expression positively correlated with IRF1 in HCC cells. Immunoprecipitation assay showed the binding between CHK1 and IRF1. Cisplatin and CHK1 inhibition upregulate MICA expression through IRF1-mediated transcriptional effects. A novel specific cis-acting IRF response element was identified at -1756 bp in the MICA promoter region that bound IRF1 to induce MICA gene transcription. MICA may increase NK cell and CD8+T cell infiltration in HCC. CONCLUSIONS: DNA damage regulates the interaction of CHK1 and IRF1 to activate anti-tumor immunity via the IRF1-MICA pathway in HCC.

14.
Surg Technol Int ; 412022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36413787

RESUMEN

BACKGROUND: Keloid is characterized by excessive collagen accumulation and fibroblast growth, which are fibroproliferative disorders of injured skin, causing functional limitations. Studies have shown that adipose-derived stem cells (ADSCs) inhibit the bioactivity and fibrosis of keloid fibroblasts. However, the molecular mechanism of this effect of ADSCs on keloid formation has not been fully elucidated. METHODS: This in vitro study used fibroblasts obtained from keloids. A consensus gene co-expression network was constructed to focus on identifying consensus gene co-expression modules associated with keloid fibroblasts. Differentially expressed genes (DEGs) were identified between keloid fibroblasts and normal dermal fibroblasts. A functional enrichment analysis was also performed with the DAVID database. A weighted gene co-expression network analysis (WGCNA) was used to screen keloid-related modules using the "WGCNA" R package, followed by hub gene selection in modules from the Protein-protein interaction network through the STRING database. Keloid fibroblasts and ADSCs were extracted and cultured. Proliferation and apoptosis were examined using a 5-ethynyl-2-deoxyuridine (Edu) kit and flow cytometry. RESULTS: We identified 302 DEGs overlapping with a consensus analysis of clusters and a differential expression analysis between keloid fibroblasts and normal dermal fibroblasts. Most of these were involved in collagen binding, extracellular matrix organization, and the PI3K-Akt signaling pathway. WGCNA analysis selected a keloid-associated brown module. ITGA2 was identified as a novel marker in hub genes from the PPI network based on the degree and function of collagen modulation. Furthermore, the proliferation ability of keloid fibroblasts cultured in ADSC medium was inhibited while apoptosis was dramatically increased. Overexpression of ITGA2 reversed the decrease in ADSC-induced apoptosis and increased ADSC-reduced proliferation. CONCLUSION: Our study demonstrated that activation of ITGA2 plays a crucial role in ADSC-induced keloid fibroblast apoptosis and anti-proliferation effects. These results also improved our understanding of the molecular mechanism of the pathogenesis of keloid in response to ADSCs and may contribute to the further development of keloid therapy.

15.
Front Neurosci ; 16: 951942, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36225732

RESUMEN

In the development of oligodendrocytes in the central nervous systems, the inner and outer tongue of the myelin sheath tend to be located within the same quadrant, which was named as Peters quadrant mystery. In this study, we conduct in silico investigations to explore the possible mechanisms underlying the Peters quadrant mystery. A biophysically detailed model of oligodendrocytes was used to simulate the effect of the actional potential-induced electric field across the myelin sheath. Our simulation suggests that the paranodal channel connecting the inner and outer tongue forms a low impedance route, inducing two high-current zones at the area around the inner and outer tongue. When the inner tongue and outer tongue are located within the same quadrant, the interaction of these two high-current-zones will induce a maximum amplitude and a polarity reverse of the voltage upon the inner tongue, resulting in the same quadrant phenomenon. This model indicates that the growth of myelin follows a simple principle: an external negative or positive E-field can promote or inhibit the growth of the inner tongue, respectively.

16.
Nanomaterials (Basel) ; 12(19)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36234573

RESUMEN

Neural interfaces provide a window for bio-signal modulation and recording with the assistance of neural microelectrodes. However, shrinking the size of electrodes results in high electrochemical impedance and low capacitance, thus limiting the stimulation/recording efficiency. In order to achieve critical stability and low power consumption, here, nanocone-shaped platinum (Pt) with an extensive surface area is proposed as an adhesive layer on a bare Pt substrate, followed by the deposition of a thin layer of iridium oxide (IrOx) to fabricate high-performance nanocone-array-based Pt-IrOx neural microelectrodes (200 µm in diameter). A uniform nanocone-shaped Pt with significant roughness is created via controlling the ratio of NH4+ and Pt4+ ions in the electrolyte, which can be widely applicable for batch production on multichannel flexible microelectrode arrays (fMEAs) and various substrates with different dimensions. The Pt-IrOx nanocomposite-coated microelectrode presents a significantly low impedance down to 0.72 ± 0.04 Ω cm2 at 1 kHz (reduction of ~92.95%). The cathodic charge storage capacity (CSCc) and charge injection capacity (CIC) reaches up to 52.44 ± 2.53 mC cm-2 and 4.39 ± 0.36 mC cm-2, respectively. Moreover, superior chronic stability and biocompatibility are also observed. The modified microelectrodes significantly enhance the adhesion of microglia, the major immune cells in the central nervous system. Therefore, such a coating strategy presents great potential for biomedical and other practical applications.

17.
Front Neurosci ; 16: 951998, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36263368

RESUMEN

The physical principle of myelin development is obtained from our previous study by explaining Peter's quadrant mystery: an externally applied negative and positive E-field can promote and inhibit the growth of the inner tongue of the myelin sheath, respectively. In this study, this principle is considered as a fundamental hypothesis, named Hypothesis-E, to explain more phenomena about myelin development systematically. Specifically, the g-ratio and the fate of the Schwann cell's differentiation are explained in terms of the E-field. Moreover, an experiment is proposed to validate this theory.

18.
Cell Transplant ; 31: 9636897221129171, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36282038

RESUMEN

Premature ovarian insufficiency (POI) can cause multiple sequelae and is currently incurable. Mesenchymal stem cell (MSC) transplantation might provide an effective treatment method for POI. However, the clinical application of systemic MSC transplantation is limited by the low efficiency of cell homing to target tissue in vivo, including systemic MSC transplantation for POI treatment. Thus, exploration of methods to promote MSC homing is necessary. This study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on the migration and homing of transplanted human amnion-derived MSCs (hAD-MSCs) to ovaries in rats with chemotherapy-induced POI. For LIPUS treatment, hAD-MSCs were exposed to LIPUS or sham irradiation. Chemokine receptor expressions in hAD-MSCs were detected by polymerase chain reaction (PCR), Western blot, and immunofluorescence assays. hAD-MSC migration was detected by wound healing and transwell migration assays. Cyclophosphamide-induced POI rat models were established to evaluate the effects of LIPUS on the homing of systemically transplanted hAD-MSCs to chemotherapy-induced POI ovaries in vivo. We found that hAD-MSCs expressed chemokine receptors. The LIPUS promoted the expression of chemokine receptors, especially CXCR4, in hAD-MSCs. SDF-1 induced hAD-MSC migration. The LIPUS promoted hAD-MSC migration induced by SDF-1 through SDF-1/CXCR4 axis. SDF-1 levels significantly increased in ovaries induced by chemotherapy in POI rats. Pretreating hAD-MSCs with LIPUS increased the number of hAD-MSCs homing to ovaries in rats with chemotherapy-induced POI to some extent. However, the difference was not significant. Both hAD-MSC and LIPUS-pretreated hAD-MSC transplantation reduced ovarian injuries and improved ovarian function in rats with chemotherapy-induced POI. CXCR4 antagonist significantly reduced the number of hAD-MSCs- and LIPUS-pretreated hAD-MSCs homing to POI ovaries, and further reduced their efficacy in POI treatment. According to these findings, pretreating MSCs with LIPUS before transplantation might provide a novel, convenient, and safe technique to explore for improving the homing of systemically transplanted MSCs to target tissue.


Asunto(s)
Antineoplásicos , Menopausia Prematura , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Insuficiencia Ovárica Primaria , Femenino , Ratas , Humanos , Animales , Amnios/metabolismo , Células Madre Mesenquimatosas/metabolismo , Insuficiencia Ovárica Primaria/inducido químicamente , Insuficiencia Ovárica Primaria/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Receptores CXCR4/metabolismo , Menopausia Prematura/metabolismo , Ondas Ultrasónicas , Ciclofosfamida
19.
Chem Commun (Camb) ; 58(60): 8404-8407, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35796077

RESUMEN

The therapeutic effects of platinum anticancer drugs are commonly whittled away by drug resistance, which is associated with drug efflux and the nucleotide excision repair (NER) pathway. Activation of drugs in a spatiotemporally controllable manner in the mitochondria of cancer cells is a very promising strategy to alleviate these problems. In this work, PtIV-PS2, a cisplatin-based PtIV prodrug, was designed to release cisplatin inside the mitochondria on red light exposure. This PtIV complex could be effectively reduced to PtII species under irradiation. PtIV-PS2 very effectively accumulates in the mitochondria of cancer cells through active transport. After photoactivation, PtIV-PS2 showed higher cytotoxicity than cisplatin in the cisplatin-resistant carcinoma cells and the amount of Pt in genomic DNA was elevated. Moreover, PtIV-PS2 decreased the cellular mitochondrial membrane potential (MMP) and the cellular content of ATP. This work developed a promising window for the design of controllably activated and mitochondrion-targeting PtIV prodrugs to overcome drug resistance of chemotherapy.


Asunto(s)
Antineoplásicos , Profármacos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Cisplatino/farmacología , Resistencia a Medicamentos , Resistencia a Antineoplásicos , Mitocondrias , Profármacos/farmacología , Profármacos/uso terapéutico
20.
Methods Mol Biol ; 2431: 351-364, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35412286

RESUMEN

Axonal transport is crucial for the development and survival of neurons and maintenance of neuronal function. Disruption in this active process causes diverse neurological diseases. Thus, study of the intracellular trafficking as one way to gain the knowledge of the kinetics of axonal transport is essential to understand the mechanisms underlying the neuropathology. A lot of studies have been completed in vitro with neuron cultures and tissues, which may not accurately replicate the in vivo situation. Therefore, intravital manipulations are essential to achieve this goal. Here we introduce a technique that has been widely used in our lab to study the cargo trafficking in zebrafish at single-cell resolution. We use mitochondria as a representative neuronal cargo and provide step-by-step instructions on how to label specific cargoes within zebrafish Mauthner cells. This method can also be expanded to study the kinetics of other cargoes as well as the role of molecular regulators in axonal transport.


Asunto(s)
Transporte Axonal , Pez Cebra , Animales , Transporte Axonal/fisiología , Axones/metabolismo , Neuronas
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