Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 93
Filtrar
1.
Eur J Pediatr ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38954007

RESUMEN

To develop a nomogram model for predicting contralateral patent processus vaginalis in children with unilateral inguinal hernia or hydrocele. A retrospective analysis was conducted on 259 children with unilateral inguinal hernia or hydrocele who underwent laparoscopic surgery at the Southern Hospital of Southern Medical University from January 2021 to December 2023. The patients were randomly divided into a training set (n = 207) and a validation set (n = 52) in an 8:2 ratio to analyze the characteristics of CPPV. Multivariate logistic regression analysis was used to screen for independent risk factors for CPPV, and a nomogram prediction model was constructed. The predictive ability, calibration, and clinical net benefit of the model were evaluated by plotting receiver operating characteristic (ROC) curves, calibration curves (HL), and clinical decision curves (DCA). Among children under 1 year old, the laparoscopic exploration revealed a CPPV incidence rate of 55.17%. The incidence rates for children aged 2-10 years ranged from 29.03 to 39.13%, and the incidence rate for children aged 11-14 years was 21.21%. Multivariate logistic regression analysis showed that age (OR = 0.9, 95%CI 0.82-0.99, P = 0.035) and female gender (OR = 2.42, 95%CI 1.21-4.83, P = 0.013) were independent risk factors for CPPV, and the incidence of CPPV decreased with age. The area under the ROC curve (AUC) for the training set of the constructed model was 0.632, and the AUC for the validation set was 0.708. The Hosmer-Lemeshow goodness-of-fit test indicated good model fit (training set P = 0.085, validation set P = 0.221), and the DCA curve suggested good clinical benefit.The nomogram model developed in this study demonstrates good clinical value. Children with unilateral inguinal hernia or hydrocele who are younger in age and female gender should undergo careful intraoperative exploration for the presence of CPPV. What is Known: • The probability of developing inguinal hernia in children with CPPV is 11%-25%, and redo surgery can increase surgical risks and financial burden. • The risk factors of unilateral inguinal hernia combined with CPPV are controversial. What is New: • Age and female gender are independent risk factors for CPPV. • A nomogram prediction model was constructed to provide a theoretical basis as well as an assessment tool for preoperative evaluation of whether children with unilateral indirect inguinal hernia are susceptible to CPPV.

2.
Adv Mater ; 36(24): e2314346, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582970

RESUMEN

Electrowetting-on-dielectric (EWOD), recognized as the most successful electrical droplet actuation method, is essential in diverse applications, ranging from thermal management to microfluidics and water harvesting. Despite significant advances, it remains challenging to achieve repeatability, high speed, and simple circuitry in EWOD-based droplet manipulation on superhydrophobic surfaces. Moreover, its efficient operation typically requires electrode arrays and sophisticated circuit control. Here, a newly observed droplet manipulation phenomenon on superhydrophobic surfaces with orbital EWOD (OEW) is reported. Due to the asymmetric electrowetting force generated on the orbit, flexible and versatile droplet manipulation is facilitated with OEW. It is demonstrated that OEW droplet manipulation on superhydrophobic surfaces exhibits higher speed (up to 5 times faster), enhanced functionality (antigravity), and manipulation of diverse liquids (acid, base, salt, organic, e.g., methyl blue, artificial blood) without contamination, and good durability after 1000 tests. It is envisioned that this robust droplet manipulation strategy using OEW will provide a valuable platform for various processes involving droplets, spanning from microfluidic devices to controllable chemical reactions. The previously unreported droplet manipulation phenomenon and control strategy shown here can potentially upgrade EWOD-based microfluidics, antifogging, anti-icing, dust removal, and beyond.

3.
Small ; : e2308809, 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38041445

RESUMEN

The rational design of absorber size is a promising strategy for obtaining excellent electromagnetic wave (EMW) absorption performance. However, achieving controllable tuning of the material size through simple methods is challenging and the associated EMW attenuation mechanisms are still unclear. In this study, the sizes of metal-organic frameworks (MOFs) are successfully tailored by changing the growth time and the molar ratio of iron (Fe)/organic ligands. The lateral and vertical lengths of MOFs vary in the range of 200 nm to 2 µm and 100 nm to 1 µm, respectively. Both experiments and simulations confirm that the decrease of MOF size favors the formation of more conductive networks, which is beneficial for improving the conductivity loss. Meanwhile, the micromagnetic simulation reveals that the magnetic coupling can be effectively enhanced by the decrease of MOF size, which is conducive to the improvement of magnetic loss, especially in low-frequency range. The reflection loss of Fe-based MOFs with optimized size reaches -46.4 dB at 6.2 GHz with an effective absorption bandwidth of 3.1 GHz. This work illustrates the important role of size effect in EMW dissipation and provides an effective strategy for enhancing the low-frequency EMW absorption performance.

4.
Small ; 19(36): e2301992, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37127857

RESUMEN

High-performance microwave absorption (MA) materials have attracted more and more attention because they can effectively prevent microwave radiation and interference from electronic devices. Herein, a new type of MA composite is constructed by introducing carbon nanotubes (CNTs)-anchored metal-organic framework derivatives (MOFDs) into a conductive carbon nanocoil (CNC) network, denoted as CNC/CNT-MOFD. The CNC/MOFD shows a wide effective absorption band of 6.7 GHz under a filling ratio of only 9% in wax-matrix. This is attributed to the hierarchical and porous structures of MOFD bridged by the uniformly dispersed conductive CNC network and the cross-polarization induced by the 3D spiral CNCs. Besides, the as-grown 1D CNTs improve space utilization, porosity, and polarization loss of the composites, resulting in the increase of imaginary permittivity, which further realizes impedance matching and energy attenuation. The Ni nanoparticles in layers of MOFD and at the tips of CNTs generate magnetic loss, promoting the low-frequency absorption ability. Resultantly, RCS values of the optimized composite in all tested theta (θ) ranges are less than -25 dB m2 at 9.5 GHz, effectively reducing the probability of the target detected by the radar.

5.
Cell Prolif ; 56(11): e13486, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37096780

RESUMEN

Blood supply shortages, especially the shortage of rare blood types, threaten the current medical system. Research on stem cells has shed light on in vitro blood cell manufacturing. The in vitro production of universal red blood cells (RBCs) from induced pluripotent stem cells (iPSCs) has become the focus of transfusion medicine. To obtain O-type Rh D-negative blood, we developed O-type Rh D-negative human (h)iPSCs using homology-directed repair (HDR)-based CRISPR/Cas9. HuAiPSCs derived from human umbilical arterial endothelial cells and showing haematopoietic differentiation preferences were selected for gene modification. Guide RNAs (gRNAs) were selected, and a donor template flanked by gRNA-directed homologous arms was set to introduce a premature stop code to RHD exon 2. CRISPR/Cas9 gene editing has resulted in the successful generation of an RHD knockout cell line. The HuAiPSC-A1-RHD-/- cell line was differentiated into haematopoietic stem/progenitor cells and subsequently into erythrocytes in the oxygen concentration-optimized differentiation scheme. HuAiPSC-A1-RHD-/- derived erythrocytes remained positive for the RBC markers CD71 and CD235a. These erythrocytes did not express D antigen and did not agglutinate in the presence of anti-Rh D reagents. In conclusion, taking the priority of haematopoietic preference hiPSCs, the HDR-based CRISPR/Cas9 system and optimizing the erythroid-lineage differentiation protocol, we first generated O-type Rh D-negative universal erythrocytes from RHD knockout HuAiPSCs. Its production is highly efficient and shows great potential for clinical applications.


Asunto(s)
Sistemas CRISPR-Cas , Células Madre Pluripotentes Inducidas , Humanos , Sistemas CRISPR-Cas/genética , Células Endoteliales , Eritrocitos/metabolismo , Edición Génica/métodos , Línea Celular , Células Madre Pluripotentes Inducidas/metabolismo
6.
Arterioscler Thromb Vasc Biol ; 43(5): 697-712, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36951064

RESUMEN

BACKGROUND: The major obstacle for applications of human induced pluripotent stem cells (hiPSCs) is efficient and controlled lineage-specific differentiation. Hence, a deeper understanding of the initial populations of hiPSCs is required to instruct proficient lineage commitment. METHODS: hiPSCs were generated from somatic cells by transduction of 4 human transcription factors (OCT4, SOX2, KLF4, and C-MYC) using Sendai virus vectors. Genome-wide DNA methylation analysis and transcriptional analysis were performed to evaluate the pluripotent capacity and somatic memory state of hiPSCs. Flow cytometric analysis and colony assays were performed to assess the hematopoietic differentiation capacity of hiPSCs. RESULTS: Here, we reveal human umbilical arterial endothelial cell-derived induced pluripotent stem cells (HuA-iPSCs) exhibit indistinguishable pluripotency in comparison with human embryonic stem cells and hiPSCs derived from other tissues of origin (umbilical vein endothelial cells, cord blood, foreskin fibroblasts, and fetal skin fibroblasts). However, HuA-iPSCs retain a transcriptional memory typical of the parental human umbilical cord arterial endothelial cells, together with a strikingly similar DNA methylation signature to umbilical cord blood-derived induced pluripotent stem cells that distinguishes them from other human pluripotent stem cells. Ultimately, HuA-iPSCs are most efficient in targeted differentiation toward hematopoietic lineage among all human pluripotent stem cells based on the functional and quantitative evaluation of both flow cytometric analysis and colony assays. Application of the Rho-kinase activator significantly reduces the effects of preferential hematopoietic differentiation in HuA-iPSCs, reflected in CD34+ cell percentage of day 7, hematopoietic/endothelial-associated gene expression, and even colony-forming unit numbers. CONCLUSIONS: Collectively, our data suggest that somatic cell memory may predispose HuA-iPSCs to differentiate more amenably into hematopoietic fate, bringing us closer to generating hematopoietic cell types in vitro from nonhematopoietic tissue for therapeutic applications.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Endoteliales/metabolismo , Diferenciación Celular/genética , Cordón Umbilical , Reprogramación Celular
7.
Chinese Pharmacological Bulletin ; (12): 340-347, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1013862

RESUMEN

Aim To explore and verify the possible mechanism of Jiawei Duhuo Jisheng Mixture(JDJM)in the treatment on Knee Osteoarthritis(KOA)via using network pharmacology and animal experiment. Methods The ingredients of JDJM and relevant targets were collected from TCMSP and BATMAN-TCM database. The KOA-related targets were collected from GeneCard, OMIM and GEO databases. The common targets were acquired by intersecting ingredients-related and KOA-related targets, and then the Ingredient-Disease-Target Network and PPI network were constructed by Cytoscape 3.7.2 software and STRING platform. GO and KEGG enrichment analysis were performed based on Metascape database. Finally, the key targets and relevant mechanism were validated via animal experiment. Results In the network pharmacology study, 180 active ingredients related to treatment on KOA by JDJM were collected, and 152 common targets were confirmed. PPI network analysis showed that AKT1 might be the key targets of JDJM in the treatment on KOA. GO and KEGG enrichment analysis revealed that the key target mainly concentrated on inflammatory response and apoptosis. Animal experiment confirmed that JDJM could improve lesion in KOA rabbits, and suppress the expression levels of IL-1β, TNF-α, Caspase 3 and BAX in serum and articular fluid. AKT1 expression(including mRNA and protein)in articular cartilage was also down-regulated. Conclusions Based on the results of network pharmacology and animal experiment, JDJM may relieve KOA severity by anti-inflammatory and anti-apoptotic effects through a variety of molecular signaling pathways.

8.
Neuroscience Bulletin ; (6): 261-272, 2023.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-971551

RESUMEN

The extracellular domain (p75ECD) of p75 neurotrophin receptor (p75NTR) antagonizes Aβ neurotoxicity and promotes Aβ clearance in Alzheimer's disease (AD). The impaired shedding of p75ECD is a key pathological process in AD, but its regulatory mechanism is largely unknown. This study was designed to investigate the presence and alterations of naturally-occurring autoantibodies against p75ECD (p75ECD-NAbs) in AD patients and their effects on AD pathology. We found that the cerebrospinal fluid (CSF) level of p75ECD-NAbs was increased in AD, and negatively associated with the CSF levels of p75ECD. Transgenic AD mice actively immunized with p75ECD showed a lower level of p75ECD and more severe AD pathology in the brain, as well as worse cognitive functions than the control groups, which were immunized with Re-p75ECD (the reverse sequence of p75ECD) and phosphate-buffered saline, respectively. These findings demonstrate the impact of p75ECD-NAbs on p75NTR/p75ECD imbalance, providing a novel insight into the role of autoimmunity and p75NTR in AD.


Asunto(s)
Ratones , Animales , Enfermedad de Alzheimer/patología , Receptor de Factor de Crecimiento Nervioso , Péptidos beta-Amiloides , Autoanticuerpos , Ratones Transgénicos
9.
Ying Yong Sheng Tai Xue Bao ; 33(11): 2997-3006, 2022 Oct.
Artículo en Chino | MEDLINE | ID: mdl-36384834

RESUMEN

Livestock wastewater is an important reservoir of antibiotic resistance genes (ARGs), with high environmental risks. We investigated the seasonal variations of distribution and removal of swine wastewater originated high-risk tetracycline resistance genes (TRGs) in horizontal subsurface flow constructed wetlands. The effects of exogenous addition of tetracycline (TC) and copper ion (Cu2+) on the abundance of TRGs in effluent with single and combined pollution of antibiotic and heavy metal were studied. The results showed that all the three high-risk TRGs (tetM, tetO and tetW) were detected in swine wastewater. Wetlands could effectively reduce the ARGs, with the absolute abundance of TRGs in effluent being decreased by 1.1-2.4 and 1.7-2.9 orders of magnitude in summer and winter compared with the influent, respectively. The abundance of TRGs in wetland soils showed the characte-ristics that the outflow side was lower than the inflow side, the non-rhizosphere area was lower than the rhizosphere area, and lower in winter than in summer. In summer and winter, single and combined pollution of TC and Cu2+ in swine wastewater would increase the abundance of TRGs in effluent compared with that in the control. The constructed wetland is suitable for controlling the environmental diffusion of ARGs in livestock wastewater.


Asunto(s)
Resistencia a la Tetraciclina , Humedales , Porcinos , Animales , Resistencia a la Tetraciclina/genética , Aguas Residuales , Estaciones del Año , Genes Bacterianos , Tetraciclina , Antibacterianos
10.
Cell Death Dis ; 13(10): 886, 2022 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-36270980

RESUMEN

Erythroblast enucleation is a precisely regulated but not clearly understood process. Polycythemia shows pathological erythroblast enucleation, and we discovered a low miR-125b-5p level in terminal erythroblasts of patients with polycythemia vera (PV) compared to those of healthy controls. Exogenous upregulation of miR-125b-5p levels restored the enucleation rate to normal levels. Direct downregulation of miR-125b-5p in mouse erythroblasts simulated the enucleation issue found in patients with PV, and miR-125b-5p accumulation was found in enucleating erythroblasts, collectively suggesting the importance of miR-125b-5p accumulation for erythroblast enucleation. To elucidate the role of miR-125b-5p in enucleation, gain- and loss-of-function studies were performed. Overexpression of miR-125b-5p improved the enucleation of erythroleukemia cells and primary erythroblasts. Infused erythroblasts with higher levels of miR-125b-5p also exhibited accelerated enucleation. In contrast, miR-125b-5p inhibitors significantly suppressed erythrocyte enucleation. Intracellular imaging revealed that in addition to cytoskeletal assembly and nuclear condensation, miR-125b-5p overexpression resulted in mitochondrial reduction and depolarization. Real-time PCR, western blot analysis, luciferase reporter assays, small molecule inhibitor supplementation and gene rescue assays revealed that Bcl-2, as a direct target of miR-125b-5p, was one of the key mediators of miR-125b-5p during enucleation. Following suppression of Bcl-2, the activation of caspase-3 and subsequent activation of ROCK-1 resulted in cytoskeletal rearrangement and enucleation. In conclusion, this study is the first to reveal the pivotal role of miR-125b-5p in erythroblast enucleation.


Asunto(s)
MicroARNs , Ratones , Animales , MicroARNs/genética , Caspasa 3/genética , Eritroblastos , Regulación hacia Abajo/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética
11.
Inorg Chem ; 61(38): 15213-15224, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36083838

RESUMEN

How to accurately detect and efficiently sweep Cr(VI) from contaminated water has come into focus. Zirconium-based metal-organic frameworks (MOFs) play vital roles in water environmental chemistry due to excellent hydrolysis-resistant stability. However, as photochemical probes and photocatalysts, poor performances in detection sensitivity, selectivity, and photosensitiveness limit sole Zr-MOFs' applications. So, it is urgent to quest valid strategies to break through the dilemmas. Embedding luminous dyes into MOFs has been considered one of the most feasible avenues. Herein, a dual-emissive RhB@Zr-MOF with orange-yellow fluorescence has been assembled by in situ-encapsulating rhodamine B (RhB) into a zirconium-biquinoline-based MOF. Actually, within RhB@Zr-MOF, the aggregation fluorescence quenching (ACQ) effect of RhB molecules was effectively avoided. Notably, RhB@Zr-MOF exhibits a rapid fluorescence quenching response toward Cr(VI) ions with high selectivity, sensitivity, and anti-interference abilities. More interestingly, unlike the most widely reported fluorescence resonance energy transfer (FRET) between MOFs and encapsulated guest modules, photoinduced electron transfer from RhB to Zr-MOF has been confirmed by modeling the ground state and excited states of RhB@Zr-MOF using density functional theory (DFT) and time-dependent DFT (TD-DFT). The effective electron transfer makes RhB@Zr-MOF more sensitive in probing Cr2O72- and CrO42- ions with ultralow detection limit (DL) values of 6.27 and 5.26 ppb, respectively. Prominently, the detection sensitivity based on DL values has been increased about 6 and 9 times, respectively, compared with pristine Zr-MOF. Moreover, rather negative CB and positive VB potentials make RhB@Zr-MOF have excellent photochemical scavenging ability toward Cr(VI) and MO.


Asunto(s)
Estructuras Metalorgánicas , Circonio , Cromo , Colorantes , Estructuras Metalorgánicas/química , Rodaminas , Agua/química , Circonio/química
12.
Nanomaterials (Basel) ; 12(15)2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35957060

RESUMEN

A flexible and stretchable electrode based on polydimethylsiloxane (PDMS)-Ag nanosheet composite with low resistance and stable properties has been investigated. Under the synergistic effect of the excellent flexibility and stretchability of PDMS and the excellent electrical conductivity of Ag nanosheets, the electrode possesses a resistivity as low as 4.28 Ωm, a low resistance variation in the 0-50% strain range, a stable electrical conductivity over 1000 cycles, and a rapid recovery ability after failure caused by destructive large stretching. Moreover, the conductive mechanism of the flexible electrode during stretching is explained by combining experimental tests, theoretical models of contact point-tunneling effect, and finite element simulation. This research provides a simple and effective solution for the structure design and material selection of flexible electrodes, and an analytical method for the conductive mechanism of stretchable electrodes, which has potential for applications in flexible electronic devices, smart sensing, wearable devices, and other fields.

13.
Cell Stem Cell ; 29(8): 1229-1245.e7, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35931032

RESUMEN

Reprogramming somatic cells into megakaryocytes (MKs) would provide a promising source of platelets. However, using a pharmacological approach to generate human MKs from somatic cells remains an unmet challenge. Here, we report that a combination of four small molecules (4M) successfully converted human cord blood erythroblasts (EBs) into induced MKs (iMKs). The iMKs could produce proplatelets and release functional platelets, functionally resembling natural MKs. Reprogramming trajectory analysis revealed an efficient cell fate conversion of EBs into iMKs by 4M via the intermediate state of bipotent precursors. 4M induced chromatin remodeling and drove the transition of transcription factor (TF) regulatory network from key erythroid TFs to essential TFs for megakaryopoiesis, including FLI1 and MEIS1. These results demonstrate that the chemical reprogramming of cord blood EBs into iMKs provides a simple and efficient approach to generate MKs and platelets for clinical applications.


Asunto(s)
Plaquetas , Megacariocitos , Diferenciación Celular , Eritroblastos , Sangre Fetal , Humanos
14.
Anal Chim Acta ; 1224: 340201, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35998986

RESUMEN

The sensitivity of surface enhanced Raman spectroscopy (SERS) depends on the construction of "hot spots" and the number of analyte molecules adsorbed onto the substrates. Herein, we have constructed a kind of SERS substrate based on gold nanostars (Au NSs) coated with nickel-cobalt layered double hydroxide (LDH) using a zeolitic imidazolate skeleton as sacrificial template via nickel ions etching. LDH was used as the absorption medium for target molecules, and concurrently prevented Au NSs from agglomeration to improve stability and uniformity of the substrate. Meanwhile, encapsulated Au NSs were used as the enhancement medium for Raman detection. The porous LDH shell around the Au NSs promoted the target molecules to approach the Au NSs, which was certified by the experimental results of UV-Vis absorption and simulation analysis using the density functional theory. The detection of Rhodamine 6G solution with a concentration of 10-9 M was realized by the AuNS/LDH, and the relative standard deviation of Raman signals was less than 10%. Therefore, this work provides a new idea and a suitable structure to improve SERS signal intensity by introducing adsorption medium into the SERS substrate.


Asunto(s)
Nanopartículas del Metal , Espectrometría Raman , Adsorción , Oro/química , Nanopartículas del Metal/química , Níquel , Espectrometría Raman/métodos
15.
Angle Orthod ; 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-35849081

RESUMEN

OBJECTIVES: To analyze the mandibular retromolar space among normal-divergent adult patients with different sagittal skeletal patterns by cone-beam computed tomography (CBCT). MATERIALS AND METHODS: CBCTs of a total of 120 normal-divergent adult patients were investigated. Patients were categorized into the following three groups according to their ANB angle: skeletal Class I (48 patients), skeletal Class II (36 patients), and skeletal Class III (36 patients). Four different planes parallel to the mandibular occlusal plane were used to measure the retromolar space. The retromolar space was measured by two reference lines and then compared between different sagittal skeletal patterns groups. The incidence of root contact with the inner lingual cortex was compared among the three groups. RESULTS: The retromolar space of the Class III patients was significantly larger than that of Class I patients and Class II patients. Compared with Class I and Class III patients, Class II patients had a smaller retromolar space and higher incidence of contact with the inner cortex of the mandible. CONCLUSIONS: Class III patients had a larger retromolar space than Class I patients and Class II patients in four different planes. The mandibular retromolar space should be evaluated by CBCT in patients who need mandibular molar distalization.

16.
J Colloid Interface Sci ; 624: 320-337, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35660901

RESUMEN

Bimetallic nanostructures composited with carbonaceous materials are the potential contenders for quantitative glucose measurement owing to their unique nanostructures, high biomimetic activity, synergistic effects, good conductivity and chemical stability. In the present work, chemical vapors deposition technique has been employed to grow 3D carbon nanocoils (CNCs) with a chiral morphology on hierarchical macroporous nickel foam (NF) to get a CNCs/NF scaffold. Following, bimetallic Cu@Ni core-shell nanoparticles (CSNPs) are effectively coupled with this scaffold through a facile solvothermal route in order to fabricate a binder-free novel Cu@Ni CSNPs/CNCs/NF hybrid nanostructure. The constructed free-standing 3D hierarchical composite electrode guarantees highly efficient glucose redox activity due to core-shell synergistic effects, enhanced electrochemical active surface area, excellent electrochemical stability, improved conductivity with better ion diffusivity and accelerated reaction kinetics. Being a non-enzymatic glucose sensor, this electrode achieves highly swift response time of 0.1 s, ultra-high sensitivity of 6905 µA mM-1 cm-2, low limit of detection of 0.03 µM along with potential selectivity and good storage stability. Moreover, the proposed sensor is also tested successfully for the determination of glucose concentration in human serum samples under good recovery ranging from 96.6 to 102.1 %. The 3D Cu@Ni CSNPs/CNCs/NF composite electrode with unprecedented catalytic performance can be utilized as an ideal biomimetic catalyst in the field of non-enzymatic glucose sensing.


Asunto(s)
Nanopartículas , Níquel , Carbono , Técnicas Electroquímicas/métodos , Electrodos , Glucosa , Humanos , Níquel/química
17.
Cell Prolif ; 55(10): e13300, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35768999

RESUMEN

Mesenchymal stem cells (MSCs) are heterogeneous populations with broad application prospects in cell therapy, and using specific subpopulations of MSCs can enhance their particular capability under certain conditions and achieve better therapeutic effects. However, no studies have reported how to obtain high-quality specific MSC subpopulations in vitro culture. Here, for the first time, we established a general operation process for obtaining high-quality clinical-grade cell subpopulations from human umbilical cord MSCs (hUC-MSCs) based on particular markers. We used the MSC-CD106+ subpopulations, whose biological function has been well documented, as an example to explore and optimize the crucial links of primary preparation, pre-treatment, antibody incubation, flow sorting, quality and function test. After comprehensively evaluating the quality and function of the acquired MSC-CD106+ subpopulations, including in vitro cell viability, apoptosis, proliferation, marker stability, adhesion ability, migration ability, tubule formation ability, immunomodulatory function and in vivo wound healing ability and proangiogenic activity, we defined an important pre-treatment scheme which might effectively improve the therapeutic efficiency of MSC-CD106+ subpopulations in two critical clinical application scenarios-direct injection after cell sorting and post-culture injection into bodies. Based on the above, we tried to establish a general five-step operation procedure for acquiring high-quality clinical-grade MSC subpopulations based on specific markers, which cannot only improve their enrichment efficiency and the reliability of preclinical studies, but also provide valuable methodological guidance for the rapid clinical transformation of specific MSC subpopulations.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Células Cultivadas , Humanos , Trasplante de Células Madre Mesenquimatosas/métodos , Reproducibilidad de los Resultados , Cordón Umbilical
18.
Nanoscale ; 14(18): 7025-7038, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35471502

RESUMEN

A flexible humidity sensor based on a tissue-carbon nanocoil (CNC)-carbon nanotube (CNT) composite has been investigated. Taking advantage of the excellent water absorption of tissue and the electrical sensitivity of CNCs/CNTs to humidity, this humidity sensor obtains outstanding humidity sensing performance, including a wide sensing range of 10-90% RH, a maximum response value of 492% (ΔR/R0) at 90% RH, a maximum sensitivity of 6.16%/% RH, a good long-time stability of more than 7 days, a high humidity resolution accuracy of less than 1% RH and a fast response time of 275 ms. Furthermore, the sensor also exhibits robust bending (with a curvature of 0.322 cm-1) and folding (up to 500 times) durability, and after being made into a complex "thousand paper crane" shape it still provides stable humidity sensing performance. As a proof of concept, this humidity sensor demonstrates excellent responsivity to human breath monitoring, non-contact fingertip humidity detection, water boiling detection and air humidity monitoring, indicating great potential in the fields of wearable devices, weather forecasting systems and other intelligent humidity monitoring devices.

19.
ACS Appl Mater Interfaces ; 14(15): 17330-17339, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35384670

RESUMEN

Recently, wearable energy harvesting systems have been attracting great attention. As thermal energy is abundant in nature, developing wearable energy harvesters based on thermal energy conversion processes has been of particular interest. By integration of a high-efficient solar absorber, a pyroelectric film, and thermoelectric yarns, herein, we design a novel wearable solar-energy-driven pyrothermoelectric hybrid generator (PTEG). In contrast to those wearable pyroelectric generators and thermoelectric generators reported in previous works, our PTEG can enable effective energy harvesting from both dynamic temperature fluctuations and static temperature gradients. Under an illumination intensity of 1500 W/m2 (1.5 sun), the PTEG successfully charges two commercial capacitors to a sum voltage of 3.7 V in only 800 s, and the total energy is able to light up 73 LED light bulbs. The volumetric energy density over the two capacitors is calculated to be 67.8 µJ/cm3. The practical energy harvesting performance of the PTEG is further evaluated in the outdoor environment. The PTEG reported in this work not only demonstrates a rational structural design of high-efficient wearable energy harvesters but also paves a new pathway to integrate multiple energy conversion technologies for solar energy collection.

20.
Stem Cell Res Ther ; 13(1): 54, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-35123563

RESUMEN

BACKGROUND: Ex vivo production of induced megakaryocytes (MKs) and platelets from stem cells is an alternative approach for supplying transfusible platelets. However, it is difficult to generate large numbers of MKs and platelets from hematopoietic stem cells and progenitor cells (HSPCs). METHODS: To optimize the differentiation efficiency of megakaryocytic cells from HSPCs, we first employed a platelet factor 4 (PF4)-promoter reporter and high-throughput screening strategy to screen for small molecules. We also investigated the effects and possible mechanisms of candidate small molecules on megakaryocytic differentiation of human HSPCs. RESULTS: The small molecule Ricolinostat remarkably promoted the expression of PF4-promoter reporter in the megakaryocytic cell line. Notably, Ricolinostat significantly enhanced the cell fate commitment of MK progenitors (MkPs) from cord blood HSPCs and promoted the proliferation of MkPs based on cell surface marker detection, colony-forming unit-MK assay, and quantitative real-time PCR analyses. MkPs generated from Ricolinostat-induced HSPCs differentiated into mature MKs and platelets. Mechanistically, we found that Ricolinostat enhanced MkP fate mainly by inhibiting the secretion of IL-8 and decreasing the expression of the IL-8 receptor CXCR2. CONCLUSION: The addition of Ricolinostat to the culture medium promoted MkP differentiation from HSPCs and enhanced the proliferation of MkPs mainly by suppressing the IL-8/CXCR2 pathway. Our results can help the development of manufacturing protocols for the efficient generation of MKs and platelets from stem cells in vitro.


Asunto(s)
Ácidos Hidroxámicos , Células Progenitoras de Megacariocitos , Diferenciación Celular , Células Madre Hematopoyéticas , Humanos , Ácidos Hidroxámicos/metabolismo , Ácidos Hidroxámicos/farmacología , Megacariocitos , Pirimidinas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...