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1.
Biochem Biophys Res Commun ; 726: 150274, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-38924882

RESUMEN

Alzheimer's disease (AD) is a complex neurodegenerative condition with growing evidence implicating the gut microbiota in its pathogenesis. This study aimed to investigate the effects of NMN synbiotics, a combination of ß-nicotinamide mononucleotide (NMN), Lactobacillus plantarum, and lactulose, on the gut microbiota composition and metabolic profiles in APP/PS1 transgenic mice. Results demonstrated that NMN synbiotics led to a notable restructuring of the gut microbiota, with a decreased Firmicutes/Bacteroidetes ratio in the AD mice, suggesting a potential amelioration of gut dysbiosis. Alpha diversity indices indicated a reduction in microbial diversity following NMN synbiotics supplementation, while beta diversity analyses revealed a shift towards a more balanced microbial community structure. Functional predictions based on the 16S rRNA data highlighted alterations in metabolic pathways, particularly those related to amino acid and energy metabolism, which are crucial for neuronal health. The metabolomic analysis uncovered a significant impact of NMN synbiotics on the gut metabolome, with normalization of metabolic composition in AD mice. Differential metabolite functions were enriched in pathways associated with neurotransmitter synthesis and energy metabolism, pointing to the potential therapeutic effects of NMN synbiotics in modulating the gut-brain axis and synaptic function in AD. Immunohistochemical staining observed a significant reduction of amyloid plaques formed by Aß deposition in the brain of AD mice after NMN synbiotics intervention. The findings underscore the potential of using synbiotics to ameliorate the neurodegenerative processes associated with Alzheimer's disease, opening new avenues for therapeutic interventions.


Asunto(s)
Enfermedad de Alzheimer , Precursor de Proteína beta-Amiloide , Modelos Animales de Enfermedad , Microbioma Gastrointestinal , Ratones Transgénicos , Simbióticos , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/dietoterapia , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/microbiología , Simbióticos/administración & dosificación , Ratones , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Presenilina-1/metabolismo , Presenilina-1/genética , Mononucleótido de Nicotinamida/metabolismo , Masculino , Disbiosis/metabolismo , Disbiosis/microbiología , Disbiosis/dietoterapia , Disbiosis/terapia
2.
Micromachines (Basel) ; 15(4)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38675282

RESUMEN

To enhance the applicability of dual-phase high-entropy alloys (HEAs) like Fe32Cr33Ni29Al3Ti3, fabricated via laser beam power bed fusion (LB-PBF), a focus on improving their mechanical properties is essential. As part of this effort, heat treatment was explored. This study compares the microstructure and mechanical properties of the as-printed sample with those cooled in water after undergoing heat treatment at temperatures ranging from 1000 to 1200 °C for 1 h. Both pre- and post-treatment samples reveal a dual-phase microstructure comprising FCC and BCC phases. Although heat treatment led to a reduction in tensile and yield strength, it significantly increased ductility compared to the as-printed sample. This strength-ductility trade-off is related to changes in grain sizes with ultrafine grains enhancing strength and micron grains optimizing ductility, also influencing the content of FCC/BCC phases and dislocation density. In particular, the sample heat-treated at 1000 °C for 1 h and then water-cooled exhibited a better combination of strength and ductility, a yield strength of 790 MPa, and an elongation of 13%. This research offers innovative perspectives on crafting dual-phase HEA of Fe32Cr33Ni29Al3Ti3, allowing for tailorable microstructure and mechanical properties through a synergistic approach involving LB-PBF and heat treatment.

3.
Eur J Pharmacol ; 964: 176291, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38158115

RESUMEN

OBJECTIVE: To identify therapeutic targets for malignant rhabdoid tumors of kidney (MRTK) and to investigate the effects and underlying mechanism of doxycycline hydrochloride on these tumors. METHODS: Gene expression and clinical data of MRTK were retrieved from the TARGET database. Differentially expressed genes (DEGs) and prognostic-related genes (PRGs) were selected through a combination of statistical analyses. The functional roles of MMP17 and MMP1 were elucidated through RNA overexpression and intervention experiments. Furthermore, in vitro and in vivo studies provided evidence for the inhibitory effect of doxycycline hydrochloride on MRTK. Additionally, transcriptome sequencing was employed to investigate the underlying molecular mechanisms. RESULTS: 3507 DEGs and 690 PRGs in MRTK were identified. Among these, we focused on 41 highly expressed genes associated with poor prognosis and revealed their involvement in extracellular matrix regulatory pathways. Notably, MMP17 and MMP1 stood out as particularly influential genes. When these genes were knocked out, a significant inhibition of proliferation, invasion and migration was observed in G401 cells. Furthermore, our study explored the impact of the matrix metalloproteinase inhibitor, doxycycline hydrochloride, on the malignant progression of G401 both in vitro and in vivo. Combined with sequencing data, the results indicated that doxycycline hydrochloride effectively inhibited MRTK progression, due to its ability to suppress the expression of MMP17 and MMP1 through the PI3K-Akt signaling pathway. CONCLUSION: Doxycycline hydrochloride inhibits the expression of MMP17 and MMP1 through the PI3K-Akt signaling pathway, thereby inhibiting the malignant progression of MRTK in vivo and in vitro.


Asunto(s)
Doxiciclina , Neoplasias Renales , Metaloproteinasa 17 de la Matriz , Tumor Rabdoide , Humanos , Doxiciclina/farmacología , Doxiciclina/uso terapéutico , Riñón/patología , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 17 de la Matriz/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tumor Rabdoide/tratamiento farmacológico , Tumor Rabdoide/patología , Transducción de Señal
4.
Front Chem ; 11: 1280999, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37927560

RESUMEN

Introduction: The rising incidence of type 2 diabetes has seriously affected international public health. The search for more drugs that can effectively treat diabetes has become a cutting-edge trend in research. Coenzyme Q10 (CoQ10) has attracted much attention in the last decade due to its wide range of biological activities. Many researchers have explored the clinical effects of CoQ10 in patients with type 2 diabetes. However, CoQ10 has low bio-availability due to its high lipophilicity. Therefore, we have structurally optimized CoQ10 in an attempt to exploit the potential of its pharmacological activity. Methods: A novel coenzyme Q10 derivative (L-50) was designed and synthesized by introducing a group containing bromine atom and hydroxyl at the terminal of coenzyme Q10 (CoQ10), and the antidiabetic effect of L-50 was investigated by cellular assays and animal experiments. Results: Cytotoxicity results showed that L-50 was comparatively low toxicity to HepG2 cells. Hypoglycemic assays indicated that L-50 could increase glucose uptake in IR-HepG2 cells, with significantly enhanced hypoglycemic capacity compared to the CoQ10. In addition, L-50 improved cellular utilization of glucose through reduction of reactive oxygen species (ROS) accumulated in insulin-resistant HepG2 cells (IR-HepG2) and regulation of JNK/AKT/GSK3ß signaling pathway, resulting in hypoglycemic effects. Furthermore, the animal experiments demonstrated that L-50 could restore the body weight of HFD/STZ mice. Notably, the findings suggested that L-50 could improve glycemic and lipid metabolism in HFD/STZ mice. Moreover, L-50 could increase fasting insulin levels (FINS) in HFD/STZ mice, leading to a decrease in fasting blood glucose (FBG) and hepatic glycogen. Furthermore, L-50 could recover triglycerides (TG), total cholesterol (T-CHO), lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) levels in HFD/STZ mice. Discussion: The addition of a bromine atom and a hydroxyl group to CoQ10 could enhance its anti-diabetic activity. It is anticipated that L-50 could be a promising new agent for T2DM.

5.
Eur J Med Res ; 28(1): 503, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37941038

RESUMEN

BACKGROUND: Neuroblastoma (NB) is the most common extracranial malignant solid tumor in children. Due to drug resistance to radiotherapy and chemotherapy, mainly due to the existence of cancer stem cells (CSCs), some children still have a poor prognosis. Therefore, researchers have focused their attention on CSCs. Our research group successfully constructed cancer stem cell-like cells named Piwil2-iCSCs by reprogramming human preputial fibroblasts (FBs) with the PIWIL2 gene in the early stage, and Piwil2-iCSCs were confirmed to induce the formation of embryonic tumors. PiRNAs, noncoding small RNAs that interact with PIWI proteins, play important roles in a variety of tumors. Therefore, our study aimed to explore the role of differentially expressed (DE) piRNAs derived from sequencing of Piwil2-iCSCs in NB. METHODS: The DE piRNAs in Piwil2-iCSCs were screened using high-throughput sequencing and further verified in NB tissues and cells. An unknown piRNA, named piRNA-MW557525, showed obvious downregulation in NB. Thus we studied the effect of piRNA-MW557525 on the biological behavior of NB through in vitro and in vivo experiments. On this basis, we successfully constructed a stably transfected NB cell line overexpressing piRNA-MW557525 and performed transcriptome sequencing to further explore the mechanism of piRNA-MW557525 in NB. RESULTS: In vitro, piRNA-MW557525 inhibited NB cell proliferation, migration and invasion and induced apoptosis; in vivo, piRNA-MW557525 significantly reduced the volume and weight of tumors and inhibited their proliferation, migration and invasion. piRNA-MW557525 overexpression induced G0/G1 phase arrest in NB cells via activation of the P53-P21-CDK2-Cyclin E signaling pathway thus inhibiting NB growth. CONCLUSIONS: Our findings show that piRNA-MW557525 functions as a tumor suppressor gene in NB and may serve as an innovative biomarker and possible therapeutic target for NB.


Asunto(s)
Neuroblastoma , ARN de Interacción con Piwi , Niño , Humanos , Proteína p53 Supresora de Tumor/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Neuroblastoma/genética , Neuroblastoma/patología , Fase G1/genética , Proliferación Celular/genética , Transducción de Señal/genética , Línea Celular Tumoral , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo
6.
Nanomaterials (Basel) ; 13(20)2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37887940

RESUMEN

Single LiNbO3 (LNO) crystals are widely utilized in surface acoustic wave devices, optoelectronic devices, and novel ferroelectric memory devices due to their remarkable electro-optic and piezoelectric properties, and high saturation and remnant polarizations. However, challenges remain regarding their nanofabrication that hinder their applications. The prevailing etching techniques for LNO encompass dry etching, wet etching, and focused-ion-beam etching, each having distinct merits and demerits. Achieving higher etching rates and improved sidewall angles presents a challenge in LNO nanofabrication. Building upon the current etching researches, this study explores various etching methods using instruments capable of generating diverse plasma densities, such as dry etching in reactive ion etching (RIE) and inductively coupled plasma (ICP), proton exchange-enhanced etching, and wet chemical etching following high-temperature reduction treatment, as well as hybrid dry and wet etching. Ultimately, after employing RIE dry etching combined with wet etching, following a high-temperature reduction treatment, an etching rate of 10 nm/min and pretty 90° sidewall angles were achieved. Furthermore, high etching rates of 79 nm/min with steep sidewall angles of 83° were obtained using ICP dry etching. Additionally, using SiO2 masks, a high etching rate of 108 nm/min and an etching selectivity ratio of 0.86:1 were achieved. Distinct etching conditions yielded diverse yet exceptional results, providing multiple processing paths of etching for the versatile application of LNO.

7.
Artículo en Inglés | MEDLINE | ID: mdl-37883090

RESUMEN

Ferroelectric domain walls, agile nanoscale interfaces of polar order, can be selectively controlled by electric fields for their position, conformation, and function, which is ultimately the key to realizing novel low-energy memory and computing structures. LiNbO3 single-crystal domain wall memory has the advantages of high operational speed, high integration density, and virtually unlimited endurance cycles, appearing as a good solution for the next generation of highly miniaturized low-energy memories. However, the etching process poses significant challenges in the nanofabrication and high-density integration of LiNbO3 domain-wall memories. Here, we employed a hybrid etching technique to achieve smooth sidewalls with a 90° inclined angle, leading to a 24% reduction in the coercive field and a 2.5-fold increase in the linear domain wall current density with a retention time of more than 106 seconds and endurance of over 105 writing cycles. Combined with the results of X-ray diffraction patterns and X-ray photoelectric spectra, it is concluded that the excellent electrical performance is related to the formation of an oxygen-deficient LiNbO3-x layer on the sidewall surface during the wet chemical etching process, which is a conductive layer that reduces the thickness of the "dead" layer between the side electrodes and the LiNbO3 cell and rectifies the diode-like wall currents with an onset voltage reduced from 1.23 to 0.28 V. These results prove the high-density integration of ferroelectric domain-wall memories at the nanoscale and provide a new strategy applicable to the development of LiNbO3 photonic devices.

8.
ACS Appl Mater Interfaces ; 15(20): 25041-25048, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37184983

RESUMEN

Electric transport in the charged domain wall (CDW) region has emerged as a promising phenomenon for the development of next-generation ferro-resistive memory with ultrahigh data storage density. However, accurately measuring the conductivity of CDWs induced by polarization reversal remains challenging due to the polarization modulation of the Schottky barrier at the thin film-electrode interface, which could partially contribute to the collected "on" current of the device. Here, we propose carefully selecting an electrode that can suppress the effect of interfacial barrier modulation induced by polarization reversal, allowing the collected current mainly from the conductive CDWs. The experiment was conducted on epitaxial BiFeO3(001) thin-film devices with vertical and horizontal geometries. Piezo-response force microscopy scanning showed the local polarization experienced 180° rotation to form CDWs under the vertical electric field. However, devices with SrRuO3 epitaxial top electrodes still exhibit an interfacial barrier-dominated diode behavior, with the "on" current proportional to the electrode area. To identify the CDW current, more interfacial defects were introduced by the deposition of Pt top electrodes, which significantly enhanced charge injection for the compensation of the reversed polarization driven by the electric field, leading to the suppressed polarization modulation of the Schottky barrier height. It was observed that the current flow through Pt electrodes is significantly lower compared to that of SRO electrodes and appears to be primarily influenced by the electrode perimeter instead of the electrode area, indicating CDW-dominated conduction behavior in these devices. Planar nanodevices were further fabricated to support the quantitative investigation of the Pt electrode size-dependent "on" current with a linear fit of the current magnitude versus the CDW cross-sectional area. This work constitutes an essential part of understanding the role of the CDW current in ferro-resistive memory devices.

9.
BMC Womens Health ; 23(1): 224, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-37138241

RESUMEN

BACKGROUND: Female infertility is a major problem for women of reproductive-age worldwide. Oxidative stress and inflammation are involved in processes related to female infertility. Serum uric acid levels, an indicator of oxidative stress and inflammation, have rarely been reported to be associated with female infertility. This study aimed to investigate the relationship between serum uric acid levels and female infertility. METHODS: This cross-sectional study included women aged 18-44 years from the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2018. All data were extracted from NHANES questionnaires and laboratory measurements. Weighted univariable and multivariable logistic regression analyses were utilized to explore the relationship between serum uric acid and female infertility. Stratified analyses were performed based on body mass index (BMI, < 25 kg/m2 and ≥ 25 kg/m2) and age (≤ 30 years and > 30 years). The odds ratio (OR) with 95% confidence interval (CI) was used to report associations. RESULTS: A total of 2,884 women were included, of which 352 (13.30%) had infertility. Women with high serum uric acid concentrations were related to higher odds of infertility (OR = 1.20, 95%CI: 1.03-1.39) after adjusting for confounders. Compared with serum uric acid concentrations ≤ 3.72 mg/dL, women with uric acid concentrations of 4.43-5.13 mg/dL (OR = 1.65, 95%CI: 1.02-2.67) and > 5.13 mg/dL (OR = 1.86, 95%CI: 1.10-3.13) were related to higher odds of infertility. Stratified analyses showed that high serum uric acid concentrations were associated with higher odds of infertility in women with a BMI < 25 kg/m2 (OR = 1.41, 95%CI: 1.04-1.93), but not in women with a BMI ≥ 25 kg/m2 (P = 0.056). In addition, high serum uric acid concentrations were associated with higher odds of infertility in women aged > 30 years (OR = 1.23, 95%CI: 1.04-1.45), but not in women aged ≤ 30 years (P = 0.556). CONCLUSION: Women with high serum uric acid concentrations were associated with higher odds of infertility, and this association may vary by BMI and age.


Asunto(s)
Infertilidad Femenina , Ácido Úrico , Humanos , Femenino , Encuestas Nutricionales , Estudios Transversales , Inflamación
10.
Eur J Pharmacol ; 951: 175747, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37142086

RESUMEN

Malignant rhabdoid tumor of the kidney (MRTK) has an inferior prognosis and is insensitive to radiotherapy and chemotherapy. Search for novel, potent medicinal agents is urgent. Herein, data on the gene expression and clinical characteristics of malignant rhabdoid tumors (MRT) were retrieved from the TARGET database. Prognosis-related genes were identified by differential analysis and one-way cox regression analysis, and prognosis-related signalling pathways were identified by enrichment analysis. The prognosis-related genes were imported into the Connectivity Map database for query, and BKM120 was predicted and screened as a potential therapeutic agent for MRTK. A combination of high-throughput RNA sequencing and Western blot verified that the PI3K/Akt signaling pathway is associated with MRTK prognosis and is overactivated in MRTK. Our results outlined that BKM120 inhibited the proliferation, migration, and invasion ability of G401 cells and induced apoptosis and cell cycle G0/G1 phase arrest. In vivo, BKM120 inhibited tumor growth and had no significant toxic side effects. Western blot and immunofluorescence results confirmed that BKM120 could reduce the expression of PI3K and p-AKT, critical proteins of the PI3K/Akt signaling pathway. BKM120 inhibits MRTK by inhibiting PI3K/Akt signalling pathway to induce apoptosis and cell cycle G0/G1 phase arrest, which is anticipated to give the clinical treatment of MRTK a new direction.


Asunto(s)
Neoplasias Renales , Tumor Rabdoide , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proliferación Celular , Tumor Rabdoide/tratamiento farmacológico , Tumor Rabdoide/genética , Línea Celular Tumoral , Apoptosis , Fase G1
11.
Eur J Pharmacol ; 952: 175523, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-36736526

RESUMEN

Bladder outlet obstruction (BOO) can cause serious complications including kidney damage; nevertheless, there are currently no animal models for studying BOO-induced kidney damage. Mesenchymal stem cells (MSCs) are widely used in therapeutic studies of renal fibrosis. However, MSC-derived exosomes show improved safety profile and more controllable characteristics compared with those of MSCs. Herein, we established a kidney injury mouse model of partial bladder outlet obstruction (PBOO) and evaluated the effects of human umbilical cord MSC-derived exosomes (hucMSC-Exos) on PBOO-induced reflux kidney injury in this model. Exosomes were isolated from a hucMSC-conditioned medium, purified by ultracentrifugation, and examined. Living image was performed to indicate the distribution of hucMSC-Exos. The PBOO-treated mice interacted with PBS (phosphate-buffered saline) or hucMSC-Exos. Morphologic changes and expression of interstitial-fibrosis-related, cell proliferation and Wnt/ß-catenin signaling-pathway indices were evaluated. At 7 days after induction of PBOO, structural destruction of renal tubules was observed. Expression of the interstitial markers and the cellular-proliferation index increased significantly in the PBOO group compared with the control group. The isolated exosomes were 30-150 nm in diameter, showing a round shape and bilayer membrane structure with CD63, TSG101, Alix expressed, enriched in the kidney of the PBOO group. Administering hucMSC-Exos to post-PBOO mice reversed renal injury and suppressed expression of Wnt/ß-catenin signaling pathway-related proteins. hucMSC-Exos inhibited PBOO-induced kidney injury and cellular proliferation and suppressed the Wnt/ß-catenin signaling pathway. Our findings will spur the development of novel hucMSC-Exo-mediated therapies for treating patients with renal fibrosis.


Asunto(s)
Exosomas , Obstrucción del Cuello de la Vejiga Urinaria , Humanos , Ratones , Animales , Vía de Señalización Wnt , beta Catenina/metabolismo , Exosomas/metabolismo , Fibrosis , Túbulos Renales/metabolismo , Proliferación Celular
12.
IEEE Trans Cybern ; 53(2): 954-966, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34460409

RESUMEN

3-D object detection is a fundamental task in the context of autonomous driving. In the literature, cheap monocular image-based methods show a significant performance drop compared to the expensive LiDAR and stereo-images-based algorithms. In this article, we aim to close this performance gap by bridging the representation capability between 2-D and 3-D domains. We propose a novel monocular 3-D object detection model using self-supervised learning and auxiliary learning, resorting to mimicking the representations over 3-D point clouds. Specifically, given a 2-D region proposal and the corresponding instance point cloud, we supervise the feature activation from our image-based convolution network to mimic the latent feature of a point-based neural network at the training stage. While state-of-the-art (SOTA) monocular 3-D detection algorithms typically convert images to pseudo-LiDAR with depth estimation and regress 3-D detection with LiDAR-based methods, our approach seeks the power of the 2-D neural network straightforwardly and essentially enhances the 2-D module capability with latent spatial-aware representations by contrastive learning. We empirically validate the performance improvement from the feature mimicking the KITTI and ApolloScape datasets and achieve the SOTA performance on the KITTI and ApolloScape leaderboard.

13.
Mol Med ; 28(1): 155, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36514009

RESUMEN

BACKGROUND: Exenatide is a stable analogue of glucagon-like peptide 1 that can reduce postprandial hyperglycemia and has been utilized as adjunctive therapy for type 1 diabetes mellitus (T1DM). The human umbilical cord is a rich source of MSCs, and human umbilical cord mesenchymal stem cells (hUCMSCs) also show potential to enhance insulin secretion. Here, we aimed to explore the effects of hUCMSCs carrying exenatide in T1DM and further identify the possible mechanisms involved. METHODS: hUCMSCs were isolated from human umbilical cord tissues, identified, and transduced with recombinant lentivirus carrying exenatide to obtain exenatide-carrying hUCMSCs (hUCMSCs@Ex-4). RESULTS: The results showed that hUCMSCs@Ex-4 restored the blood glucose levels and body weight of NOD mice, and repressed immune cell infiltration and islet tissue changes. Additionally, in T1DM mice, treatment with hUCMSCs@Ex-4 reduced the blood glucose levels and promoted repair of islet tissue damage. Moreover, hUCMSCs@Ex-4 attenuated renal tissue lesions in T1DM mice. Applying bioinformatic analysis, the effects of hUCMSCs@Ex-4 were suggested to correlate with decreased abundance of pro-inflammatory intestinal bacteria and increased abundance of anti-inflammatory intestinal bacteria. CONCLUSION: Overall, the study indicated that hUCMSCs carrying exenatide might improve beneficial intestinal microflora abundance and promote islet tissue damage repair, thereby alleviating T1DM.


Asunto(s)
Diabetes Mellitus Tipo 1 , Microbioma Gastrointestinal , Células Madre Mesenquimatosas , Humanos , Ratones , Animales , Exenatida/farmacología , Glucemia , Ratones Endogámicos NOD
14.
Drug Deliv ; 29(1): 3291-3303, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36352741

RESUMEN

Osteosarcoma is a bone tumor with a high incidence in children and adolescents. Chemotherapy for osteosarcoma is limited, and effective targeted drugs are urgently needed to treat osteosarcoma. Exosomes as a natural nano drug delivery platform have been widely studied and proven to have good drug delivery performance. However, the low production of exosomes hinders its development as a carrier. Exosome mimetics (EMs) as an alternative product of exosomes solve the problem of low production of exosomes and maintain the good performance of exosomes as carriers. In this study, bone marrow mesenchymal stem cells (BMSCs) were sequentially extruded to generate EMs to encapsulate doxorubicin (EM-Dox) to treat osteosarcoma. The results showed that we successfully prepared EMs of BMSC, and EM-Dox was prepared using an active-loading approach. Our engineered EM-Dox demonstrated significantly more potent tumor inhibition activity and fewer side effects than free doxorubicin. This novel biological nanomedicine system provides a promising opportunity to develop novel precision medicine for osteosarcoma.


Asunto(s)
Neoplasias Óseas , Exosomas , Células Madre Mesenquimatosas , Osteosarcoma , Niño , Humanos , Adolescente , Línea Celular Tumoral , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Doxorrubicina , Neoplasias Óseas/tratamiento farmacológico
15.
Biomater Adv ; 142: 213161, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36308859

RESUMEN

PURPOSE: To develop exosome-mimetics derived from bone marrow mesenchymal stem cells (EM) as a novel nanoscale drug delivery system(nanoDDS) with improved tumor targeting activity, therapeutic effect, and biosafety, and to evaluate the therapeutic effect of doxorubicin loaded EM (EM-Dox) on neuroblastoma (NB) in vitro and in vivo. METHODS: EM was prepared by serial extrusion of bone marrow mesenchymal stem cells (BMSCs), ammonium sulfate gradient method was used to promote the active loading of doxorubicin, and EM-Dox was obtained after removal of free doxorubicin by dialysis. The obtained EM and EM-Dox were characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), Western Blot assay(WB), and the yield of exosomes and EM was further compared. Confocal fluorescent microscopy was used to verify the uptake of EM-Dox and free doxorubicin (Free-Dox) by NB cells. CCK-8 assay, cell cycle assay, and cell apoptosis assay were used to evaluate the antitumor effect of EM-Dox on NB cells in vitro. In addition, the targeted therapeutic effect and biosafety of EM-Dox against NB were evaluated in tumor-bearing nude mice. RESULTS: TEM, NTA, and WB verified that both EM and EM-Dox feature highly similar morphology, size and marker protein expression in comparison with naturally occurred exosomes, but the particle size of EM-Dox increased slightly after loading doxorubicin. The protein yield and particle yield of EM-Dox were 16.8 and 26.3-folds higher than those of exosomes, respectively. Confocal fluorescent microscopy showed that EM and doxorubicin had a definite co-localization. EM-Dox was readily internalized in two well-established human NB cell lines. The intracellular content of doxorubicin in cells treated with EM-Dox was significantly higher than that treated with Free-Dox. CCK-8 assay and flow cytometry confirmed that EM-Dox could inhibit NB cell proliferation, induce G2/M phase cell cycle arrest, and promote NB cell apoptosis in vitro. In vivo bioluminescence imaging results demonstrated that EM-Dox effectively targets NB tumors in vivo. Compared with Free-Dox, EM-Dox had a significantly increased inhibitory effect against NB tumor proliferation and progression in vivo, without inducing any myocardial injury. CONCLUSIONS: EM-Dox showed significantly increased anti-tumor activity in comparison with free doxorubicin in vitro and in vivo, and scalable EMs may represent a new class of NanoDDS that can potentially replace naturally occurred exosomes in preclinical or clinical translations.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , Neuroblastoma , Ratones , Animales , Humanos , Ratones Desnudos , Línea Celular Tumoral , Doxorrubicina/farmacología , Neuroblastoma/tratamiento farmacológico
16.
BMC Geriatr ; 22(1): 736, 2022 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-36076163

RESUMEN

OBJECTIVE: Thyroid carcinoma (TC) is the most common endocrine tumor in the human body. Papillary thyroid carcinoma (PTC) accounts for more than 80% of thyroid cancers. Accurate prediction of elderly PTC can help reduce the mortality of patients. We aimed to construct a nomogram predicting cancer-specific survival (CSS) in elderly patients with PTC. METHODS: Patient information was downloaded from the Surveillance, Epidemiology, and End Results (SEER) program. Univariate and multivariate Cox regression models were used to screen the independent risk factors for patients with PTC. The nomogram of elderly patients with PTC was constructed based on the multivariate Cox regression model. We used the concordance index (C-index), the area under the receiver operating characteristic curve (AUC) and the calibration curve to test the accuracy and discrimination of the prediction model. Decision curve analysis (DCA) was used to test the clinical value of the model. RESULTS: A total of 14,138 elderly patients with PTC were included in this study. Patients from 2004 to 2015 were randomly divided into a training set (N = 7379) and a validation set (N = 3141), and data from 2016 to 2018 were divided into an external validation set (N = 3618). Proportional sub-distribution hazard model showed that age, sex, tumor size, histological grade, TNM stage, surgery and chemotherapy were independent risk factors for prognosis. In the training set, validation set and external validation set, the C-index was 0.87(95%CI: 0.852-0.888), 0.891(95%CI: 0.866-0.916) and 0.931(95%CI:0.894-0.968), respectively, indicating that the nomogram had good discrimination. Calibration curves and AUC suggest that the prediction model has good discrimination and accuracy. CONCLUSIONS: We constructed a new nomogram to predict CSS in elderly patients with PTC. Internal cross-validation and external validation indicate that the model has good discrimination and accuracy. The predictive model can help doctors and patients make clinical decisions.


Asunto(s)
Nomogramas , Neoplasias de la Tiroides , Anciano , Humanos , Pronóstico , Programa de VERF , Cáncer Papilar Tiroideo/diagnóstico , Cáncer Papilar Tiroideo/epidemiología , Cáncer Papilar Tiroideo/terapia , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/terapia
17.
Acta Biochim Biophys Sin (Shanghai) ; 54(9): 1301-1313, 2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36148954

RESUMEN

Bacterial outer membrane vesicles (OMVs) are spherical microbubbles that contain biological content and are produced by gram-negative bacteria. The use of OMVs as adjuvants for cancer immunotherapy or as drug carriers for targeted therapies has attracted the interest of many scholars. However, it is unclear whether OMVs can exert direct antitumor effects and whether OMVs can inhibit pediatric tumors. Here, we explore the potential of Escherichia coli-derived OMVs to directly suppress neuroblastoma. Our results demonstrate the antitumor effects of OMVs in vitro and in vivo, and no serious adverse reactions were observed. OMV uptake into the cytoplasm and nucleus directly decreases cell stemness, DNA damage, apoptosis and cell cycle arrest, which may be the mechanisms by which OMVs suppress tumors. Our results demonstrate the potential of bacterial OMVs to be used as antitumor adjuvant therapies, increasing the number of candidates for the development of cancer therapies in the future. More relevant studies are urgently needed to demonstrate the efficacy and safety of OMVs.


Asunto(s)
Escherichia coli , Neuroblastoma , Niño , Humanos , Escherichia coli/metabolismo , Apoptosis , Neuroblastoma/tratamiento farmacológico , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo
18.
Stem Cells ; 40(11): 1008-1019, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-35977539

RESUMEN

p53 plays a pivotal role in maintaining the genomic stability of mouse embryonic stem cells (mESCs) through transcriptionally activating and repressing target genes. However, how p53 recognizes its repressed targets remains largely unknown. Herein, we demonstrate that Sall4 negatively regulates DNA damage induced apoptosis (DIA) of mESCs through mediating p53 recruitment to enhancers of ESC-associated genes repressed by p53 from promoters of p53-activated genes. Upon DNA damage, Sall4 is transcriptionally repressed by p53 and plays an anti-apoptotic role without altering p53 activation. Moreover, Sall4 is identified as a novel p53-interacting partner. Consistently, Sall4 exerts its anti-apoptotic function in a p53-dependent manner. Intriguingly, Sall4 depletion not only promotes the transcriptional activation of several p53-regulated pro-apoptotic genes but also compromises p53-mediated repression of ESC master transcription factors in response to DNA damage. Mechanistically, Sall4 balances p53-binding affinity between p53-activated and -repressed genes through tethering p53 to ESC enhancers. In light of our study, Sall4 may contribute to tumorigenesis by antagonizing p53-mediated apoptosis.


Asunto(s)
Proteínas de Unión al ADN , Células Madre Embrionarias de Ratones , Factores de Transcripción , Proteína p53 Supresora de Tumor , Animales , Ratones , Daño del ADN/genética , Células Madre Embrionarias de Ratones/metabolismo , Unión Proteica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo
19.
Sensors (Basel) ; 22(13)2022 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-35808326

RESUMEN

This paper presents a geometric approach for real-time forward kinematics of the general Stewart platform, which consists of two rigid bodies connected by six general serial manipulators. By describing the rigid-body motion as exponential of twist, and taking advantage of the product of exponentials formula, a step-by-step derivation of the proposed algorithm is presented. As the algorithm naturally solves all passive joint displacements, the correctness is then verified by comparing the forward-kinematic solutions from all chains. The convergence ability and robustness of the proposed algorithm are demonstrated with large amounts of numerical simulations. In all test cases, the proposed algorithm terminates within four iterations, converging with near-quadratic speed. Finally, the proposed algorithm is also implemented on a mainstream embedded motion controller. Compared with the incremental method, the proposed algorithm is more robust, with an average execution time of 0.48 ms, meeting the requirements of most applications, such as kinematic calibration, motion simulation, and real-time control.


Asunto(s)
Algoritmos , Fenómenos Biomecánicos , Simulación por Computador , Movimiento (Física)
20.
ACS Appl Mater Interfaces ; 14(31): 35389-35399, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35904812

RESUMEN

Current guidelines recommend adjuvant chemotherapy (ACT) for stage II colorectal cancer (CRC) patients by using clinical high risk factors, with which circulating tumor cells (CTCs) were not considered. Here, an assessment to detect CTCs based on subtraction enrichment mediated by magnetic beads conjugated with CD45, immunofluorescence staining of CK, and fluorescence in situ hybridization of CEP8 is established. Both CEP8- and CK-positive CTCs have the potential to improve the risk stratification of stage II CRC patients. Patients with preoperative CTCs of ≥4 had a significantly higher recurrence risk than those with preoperative CTCs of <4 in two external validation cohorts (P < 0.0001). In the subgroup with clinical high risk, when preoperative CTCs were <4, patients did not benefit from ACT (P = 0.5764); however, when preoperative CTCs were ≥4, patients received benefit from ACT (P = 0.0064). Additionally, regardless of clinical risk status and preoperative CTC levels, if postoperative CTC levels were ≥4 for more than three consecutive time points (monitoring time interval, 2-6 months), the recurrence rate was 100%. Our findings suggested that the subtraction enrichment of CTCs could provide a reliable method to stratify the recurrence risk and make therapeutic decisions after surgery in stage II CRC patients.


Asunto(s)
Neoplasias Colorrectales , Células Neoplásicas Circulantes , Biomarcadores de Tumor , Recuento de Células , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Humanos , Hibridación Fluorescente in Situ , Células Neoplásicas Circulantes/patología , Pronóstico
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