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1.
Mikrochim Acta ; 191(5): 257, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38600405

RESUMO

A new detection platform based on CaCO3-based magnetic micromotor (CaCO3@Fe3O4) integrated with graphene field effect transistor (GFET) was construct and used for on-site SARS-CoV-2 coronavirus pathogen detection. The CaCO3@Fe3O4 micromotor, which was modified with anti-SARS-CoV-2 (labelled antibody, AntiE1), can self-moved in the solution containing hydrochloric acid (HCl) and effective to capture the SARS-CoV-2 coronavirus pathogens. After magnetic field separation, the capture micromotor was detected by GFET, exhibiting a good linear relationship within the range of 1 ag/mL to 100 ng/mL and low detection limit (0.39 ag/mL). Furthermore, the detection platform was also successfully applied to detection of SARS-CoV-2 coronavirus pathogens in soil solution, indicating the potential use in on-site application.


Assuntos
Doenças Transmissíveis , Grafite , Humanos , Anticorpos , SARS-CoV-2 , Fenômenos Magnéticos
2.
J Neuroeng Rehabil ; 21(1): 49, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589875

RESUMO

BACKGROUND: Non-invasive techniques such as central intermittent theta burst stimulation (iTBS) and repetitive peripheral magnetic stimulation (rPMS) have shown promise in improving motor function for patients with stroke. However, the combined efficacy of rPMS and central iTBS has not been extensively studied. This randomized controlled trial aimed to investigate the synergistic effects of rPMS and central iTBS in patients with stroke. METHOD: In this study, 28 stroke patients were randomly allocated to receive either 1200 pulses of real or sham rPMS on the radial nerve of the affected limb, followed by 1200 pulses of central iTBS on the ipsilesional hemisphere. The patients received the intervention for 10 sessions over two weeks. The primary outcome measures were the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) and the Action Research Arm Test (ARAT). Secondary outcomes for activities and participation included the Functional Independence Measure-Selfcare (FIM-Selfcare) and the Stroke Impact Scale (SIS). The outcome measures were assessed before and after the intervention. RESULTS: Both groups showed significant improvement in FMA-UE and FIM-Selfcare after the intervention (p < 0.05). Only the rPMS + iTBS group had significant improvement in ARAT-Grasp and SIS-Strength and activity of daily living (p < 0.05). However, the change scores in all outcome measures did not differ between two groups. CONCLUSIONS: Overall, the study's findings suggest that rPMS may have a synergistic effect on central iTBS to improve grasp function and participation. In conclusion, these findings highlight the potential of rPMS as an adjuvant therapy for central iTBS in stroke rehabilitation. Further large-scale studies are needed to fully explore the synergistic effects of rPMS on central iTBS. TRIAL REGISTRATION: This trial was registered under ClinicalTrials.gov ID No.NCT04265365, retrospectively registered, on February 11, 2020.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Fenômenos Magnéticos , Reabilitação do Acidente Vascular Cerebral/métodos , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Extremidade Superior , Método Duplo-Cego
3.
J Psychiatr Res ; 173: 309-316, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569451

RESUMO

OBJECTIVE: Psychomotor retardation is a core clinical component of Major Depressive Disorder responsible for disability and is known as a treatment response marker of biological treatments for depression. Our objective was to describe cognitive and motoric measures changes during a treatment by repetitive Transcranial Magnetic Stimulation (rTMS) within the THETAD-DEP trial for treatment-resistant depression (TRD), and compare those performances at the end of treatment and one month after between responders (>50% improvement on MADRS score), partial responders (25-50%) and non-reponders (no clinically relevant improvement). Our secondary aim was to investigate baseline psychomotor performances associated with non-response and response even partial. METHODS: Fifty-four patients with treatment-resistant unipolar depression and treated by either high frequency 10 Hz rTMS or iTBS for 4 weeks (20 sessions) underwent assessment including French Retardation Rating Scale for Depression (ERD), Verbal Fluency test, and Trail Making Test A. before, just after treatment and one month later. RESULTS: 20 patients were responders (R, 21 partial responders (PR) and 13 non-responders (NR). rTMS treatment improved psychomotor performances in the R and PR groups unlike NR patients whose psychomotor performance was not enhanced by treatment. At baseline, participants, later identified as partial responders, showed significantly higher performances than non-responders. CONCLUSION: Higher cognitivo-motor performances at baseline may be associated with clinical improvement after rTMS treatment. This work highlights the value of objective psychomotor testing for the identification of rTMS responders and partial responders, and thus may be useful for patient selection and protocol individualization such as treatment continuation for early partial responders.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Resistente a Tratamento , Humanos , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Resistente a Tratamento/terapia , Transtorno Depressivo Resistente a Tratamento/complicações , Estimulação Magnética Transcraniana/métodos , Desempenho Psicomotor , Fenômenos Magnéticos , Resultado do Tratamento , Córtex Pré-Frontal/fisiologia
4.
Water Sci Technol ; 89(7): 1860-1878, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619908

RESUMO

The activated persulfate (PS) process could produce sulfate radical (SO4·-) and rapidly degrade organic pollutants. The application of Fe3O4 as a promising PS activator was limited due to the rapid conversion of Fe2+ to Fe3+ on its surface. Mo4+ on MoS2 surface could be used as a reducing site to convert Fe3+ to Fe2+, but the separation and recovery of MoS2 was complex. In this study, MoS2/Fe3O4 was prepared to accelerate the Fe3+/Fe2+ cycle on Fe3O4 surface and achieved efficient separation of MoS2. The results showed that MoS2/Fe3O4 was more effective for PS activation compared to Fe3O4 or MoS2, with a removal efficiency of 91.8% for 20 mg·L-1 tetracycline (TC) solution under the optimal conditions. Fe2+ and Mo4+ on MoS2/Fe3O4 surface acted as active sites for PS activation with the generation of SO4•-, •OH, •O2-, and 1O2. Mo4+ acted as an electron donor to promote the Fe3+/Fe2+ cycling and thus improved the PS activation capability of MoS2/Fe3O4. The degradation pathways of TC were inferred as hydroxylation, ketylation of dimethylamino group and C-N bond breaking. This study provided a promising activated persulfate-based advanced oxidation process for the efficient degradation of TC by employing MoS2/Fe3O4 as an effective activator.


Assuntos
Molibdênio , Poluentes Químicos da Água , Tetraciclina/análise , Oxirredução , Antibacterianos , Fenômenos Magnéticos , Poluentes Químicos da Água/química
5.
BMC Musculoskelet Disord ; 25(1): 253, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561728

RESUMO

BACKGROUND: The characteristics and therapeutic potential of subtypes of bone marrow mesenchymal stem cells (BMSCs) are largely unknown. Also, the application of subpopulations of BMSCs in cartilage regeneration remains poorly characterized. The aim of this study was to explore the regenerative capacity of CD146-positive subpopulations of BMSCs for repairing cartilage defects. METHODS: CD146-positive BMSCs (CD146 + BMSCs) were sorted by self-developed CD146-specific lipid magnetic spheres (CD146-LMS). Cell surface markers, viability, and proliferation were evaluated in vitro. CD146 + BMSCs were subjected to in vitro chondrogenic induction and evaluated for chondrogenic properties by detecting mRNA and protein expression. The role of the CD146 subpopulation of BMSCs in cartilage damage repair was assessed by injecting CD146 + BMSCs complexed with sodium alginate gel in the joints of a mouse cartilage defect model. RESULTS: The prepared CD146-LMS had an average particle size of 193.7 ± 5.24 nm, an average potential of 41.9 ± 6.21 mv, and a saturation magnetization intensity of 27.2 Am2/kg, which showed good stability and low cytotoxicity. The sorted CD146 + BMSCs highly expressed stem cell and pericyte markers with good cellular activity and cellular value-added capacity. Cartilage markers Sox9, Collagen II, and Aggrecan were expressed at both protein and mRNA levels in CD146 + BMSCs cells after chondrogenic induction in vitro. In a mouse cartilage injury model, CD146 + BMSCs showed better function in promoting the repair of articular cartilage injury. CONCLUSION: The prepared CD146-LMS was able to sort out CD146 + BMSCs efficiently, and the sorted subpopulation of CD146 + BMSCs had good chondrogenic differentiation potential, which could efficiently promote the repair of articular cartilage injury, suggesting that the sorted CD146 + BMSCs subpopulation is a promising seed cell for cartilage tissue engineering.


Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Animais , Camundongos , Cartilagem Articular/metabolismo , Antígeno CD146/metabolismo , Diferenciação Celular , Células Cultivadas , Células-Tronco Mesenquimais/metabolismo , Células da Medula Óssea/metabolismo , Condrogênese , RNA Mensageiro/metabolismo , Fenômenos Magnéticos , Lipídeos
6.
Europace ; 26(4)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38584395

RESUMO

AIMS: A few studies have reported the effect and safety of pulsed field ablation (PFA) catheters for ablating atrial fibrillation (AF), which were mainly based on basket-shaped or flower-shaped designs. However, the clinical application of a circular-shaped multi-electrode catheter with magnetic sensors is very limited. To study the efficacy and safety of a PFA system in patients with paroxysmal AF using a circular-shaped multi-electrode catheter equipped with magnetic sensors for pulmonary vein isolation (PVI). METHODS AND RESULTS: A novel proprietary bipolar PFA system was used for PVI, which utilized a circular-shaped multi-electrode catheter with magnetic sensors and allowed for three-dimensional model reconstruction, mapping, and ablation in one map. To evaluate the efficacy, efficiency, and safety of this PFA system, a prospective, multi-centre, single-armed, pre-market clinical study was performed. From July 2021 to December 2022, 151 patients with paroxysmal AF were included and underwent PVI. The study examined procedure time, immediate success rate, procedural success rate at 12 months, and relevant complications. In all 151 patients, all the pulmonary veins were acutely isolated using the studied system. Pulsed field ablation delivery was 78.4 ± 41.8 times and 31.3 ± 16.7 ms per patient. Skin-to-skin procedure time was 74.2 ± 29.8 min, and fluoroscopy time was 13.1 ± 7.6 min. The initial 11 (7.2%) cases underwent procedures with deep sedation anaesthesia, and the following cases underwent local anaesthesia. In the initial 11 cases, 4 cases (36.4%) presented transient vagal responses, and the rest were all successfully preventatively treated with atropine injection and rapid fluid infusion. No severe complications were found during or after the procedure. During follow-up, 3 cases experienced atrial flutter, and 11 cases had AF recurrence. The estimated 12-month Kaplan-Meier of freedom from arrhythmia was 88.4%. CONCLUSION: The PFA system, comprised of a circular PFA catheter with magnetic sensors, could rapidly achieve PVI under three-dimensional guidance and demonstrated excellent safety with comparable effects.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Veias Pulmonares/cirurgia , Resultado do Tratamento , Estudos Prospectivos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Cateteres , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Fenômenos Magnéticos , Recidiva
7.
Int J Nanomedicine ; 19: 3143-3166, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585472

RESUMO

Background: The ability of nanomaterials to induce osteogenic differentiation is limited, which seriously imped the repair of craniomaxillofacial bone defect. Magnetic graphene oxide (MGO) nanocomposites with the excellent physicochemical properties have great potential in bone tissue engineering. In this study, we aim to explore the craniomaxillofacial bone defect repairment effect of MGO nanocomposites and its underlying mechanism. Methods: The biocompatibility of MGO nanocomposites was verified by CCK8, live/dead staining and cytoskeleton staining. The function of MGO nanocomposites induced osteogenic differentiation of BMSCs was investigated by ALP activity detection, mineralized nodules staining, detection of osteogenic genes and proteins, and immune-histochemical staining. BMSCs with or without MGO osteogenic differentiation induction were collected and subjected to high-throughput circular ribonucleic acids (circRNAs) sequencing, and then crucial circRNA circAars was screened and identified. Bioinformatics analysis, Dual-luciferase reporter assay, RNA binding protein immunoprecipitation (RIP), fluorescence in situ hybridization (FISH) and osteogenic-related examinations were used to further explore the ability of circAars to participate in MGO nanocomposites regulation of osteogenic differentiation of BMSCs and its potential mechanism. Furthermore, critical-sized calvarial defects were constructed and were performed to verify the osteogenic differentiation induction effects and its potential mechanism induced by MGO nanocomposites. Results: We verify the good biocompatibility and osteogenic differentiation improvement effects of BMSCs mediated by MGO nanocomposites. Furthermore, a new circRNA-circAars, we find and identify, is obviously upregulated in BMSCs mediated by MGO nanocomposites. Silencing circAars could significantly decrease the osteogenic ability of MGO nanocomposites. The underlying mechanism involved circAars sponging miR-128-3p to regulate the expression of SMAD5, which played an important role in the repair craniomaxillofacial bone defects mediated by MGO nanocomposites. Conclusion: We found that MGO nanocomposites regulated osteogenic differentiation of BMSCs via the circAars/miR-128-3p/SMAD5 pathway, which provided a feasible and effective strategy for the treatment of craniomaxillofacial bone defects.


Assuntos
Grafite , MicroRNAs , Nanocompostos , MicroRNAs/genética , Osteogênese/genética , RNA Circular , Hibridização in Situ Fluorescente , Óxido de Magnésio , Células Cultivadas , Regeneração Óssea , Fenômenos Magnéticos , Diferenciação Celular
8.
Sci Rep ; 14(1): 8166, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589455

RESUMO

This study involves the development of a new nanocomposite material for use in biological applications. The nanocomposite was based on tragacanth hydrogel (TG), which was formed through cross-linking of Ca2+ ions with TG polymer chains. The utilization of TG hydrogel and silk fibroin as natural compounds has enhanced the biocompatibility, biodegradability, adhesion, and cell growth properties of the nanobiocomposite. This advancement makes the nanobiocomposite suitable for various biological applications, including drug delivery, wound healing, and tissue engineering. Additionally, Fe3O4 magnetic nanoparticles were synthesized in situ within the nanocomposite to enhance its hyperthermia efficiency. The presence of hydrophilic groups in all components of the nanobiocomposite allowed for good dispersion in water, which is an important factor in increasing the effectiveness of hyperthermia cancer therapy. Hemolysis and 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assays were conducted to evaluate the safety and efficacy of the nanobiocomposite for in-vivo applications. Results showed that even at high concentrations, the nanobiocomposite had minimal hemolytic effects. Finally, the hyperthermia application of the hybrid scaffold was evaluated, with a maximum SAR value of 41.2 W/g measured in the first interval.


Assuntos
Fibroínas , Hipertermia Induzida , Tragacanto , Tecidos Suporte , Hidrogéis , Fenômenos Magnéticos
9.
Mikrochim Acta ; 191(5): 251, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38589663

RESUMO

Nanocomposite microbeads (average diameter = 10-100 µm) were prepared by a microemulsion-solidification method and applied to the magnetic solid-phase extraction (m-SPE) of fourteen analytes, among pesticides, drugs, and hormones, from human urine samples. The microbeads, perfectly spherical in shape to maximize the surface contact with the analytes, were composed of magnetic nanoparticles dispersed in a polylactic acid (PLA) solid bulk, decorated with multi-walled carbon nanotubes (mPLA@MWCNTs). In particular, PLA was recovered from filters of smoked electronic cigarettes after an adequate cleaning protocol. A complete morphological characterization of the microbeads was performed via Fourier-transform infrared (FTIR) spectroscopy, UV-Vis spectroscopy, thermogravimetric and differential scanning calorimetry analysis (TGA and DSC), scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). The recovery study of the m-SPE procedure showed yields ≥ 64%, with the exception of 4-chloro-2-methylphenol (57%) at the lowest spike level (3 µg L-1). The method was validated according to the main FDA guidelines for the validation of bioanalytical methods. Using liquid chromatography-tandem mass spectrometry, precision and accuracy were below 11% and 15%, respectively, and detection limits of 0.1-1.8 µg L-1. Linearity was studied in the range of interest 1-15 µg L-1 with determination coefficients greater than 0.99. In light of the obtained results, the nanocomposite microbeads have proved to be a valid and sustainable alternative to traditional sorbents, offering good analytical standards and being synthetized from recycled plastic material. One of the main objectives of the current work is to provide an innovative and optimized procedure for the recycling of a plastic waste, to obtain a regular and reliable microstructure, whose application is here presented in the field of analytical chemistry. The simplicity and greenness of the method endows the procedure with a versatile applicability in different research and industrial fields.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nanocompostos , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/química , Xenobióticos , Microesferas , Poliésteres , Extração em Fase Sólida/métodos , Nanocompostos/química , Fenômenos Magnéticos
10.
Mikrochim Acta ; 191(5): 235, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570380

RESUMO

A fast and accurate identification of Listeria monocytogenes. A new quartz crystal microbalance (QCM) aptasensor was designed for the specific and rapid detection of L. monocytogenes. Before detection of the target bacterium from samples in the QCM aptasensor, a magnetic pre-enrichment system was used to eliminate any contaminant in the samples. The prepared magnetic system was characterized using ATR-FTIR, SEM, VSM, BET, and analytical methods. The saturation magnetization values of the Fe3O4, Fe3O4@PDA, and Fe3O4@PDA@DAPEG particles were 57.2, 40.8, and 36.4 emu/g, respectively. The same aptamer was also immobilized on the QCM crystal integrated into QCM flow cell and utilized to quantitatively detect L. monocytogenes cells from the samples. It was found that a specific aptamer-magnetic pre-concentration system efficiently captured L. monocytogenes cells in a short time (approximately 10 min). The Fe3O4@PDA@DA-PEG-Apt particles provided selective isolation of L. monocytogenes from the bacteria-spiked media up to 91.8%. The immobilized aptamer content of the magnetic particles was 5834 µg/g using 500 ng Apt/mL. The QCM aptasensor showed a very high range of analytical performance to the target bacterium from 1.0 × 102 and 1.0 × 107 CFU/mL. The limit of detection (LOD) and limit of quantitation (LOQ) were 148 and 448 CFU/mL, respectively, from the feeding of the QCM aptasensor flow cell with the eluent of the magnetic pre-concentration system. The reproducibility of the aptasensor was more than 95%. The aptasensor was very specific to L. monocytogenes compared to the other Listeria species (i.e., L. ivanovii, L. innocua, and L. seeligeri) or other tested bacteria such as Staphylococcus aureus, Escherichia coli, and Bacillus subtilis. The QCM aptasensor was regenerated with NaOH solution, and the system was reused many times.


Assuntos
Aptâmeros de Nucleotídeos , Listeria monocytogenes , Técnicas de Microbalança de Cristal de Quartzo , Reprodutibilidade dos Testes , Aptâmeros de Nucleotídeos/química , Escherichia coli , Fenômenos Magnéticos
11.
Biosens Bioelectron ; 255: 116272, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38581837

RESUMO

The development of an advanced analytical platform with regard to SARS-CoV-2 is crucial for public health. Herein, we present a machine learning platform based on paper-assisted ratiometric fluorescent sensors for highly sensitive detection of the SARS-CoV-2 RdRp gene. The assay involves target-induced rolling circle amplification to generate magnetic DNAzyme, which is then detectable using the paper-assisted ratiometric fluorescent sensor. This sensor detects the SARS-CoV-2 RdRp gene with a visible-fluorescence color response. Moreover, leveraging different fluorescence responses, the ResNet algorithm of machine learning assists in accurately identifying fluorescence images and differentiating the concentration of the SARS-CoV-2 RdRp gene with over 99% recognition accuracy. The machine learning platform exhibits exceptional sensitivity and color responsiveness, achieving a limit of detection of 30 fM for the SARS-CoV-2 RdRp gene. The integration of intelligent artificial vision with the paper-assisted ratiometric fluorescent sensor presents a novel approach for the on-site detection of COVID-19 and holds potential for broader use in disease diagnostics in the future.


Assuntos
Técnicas Biossensoriais , COVID-19 , DNA Catalítico , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , Técnicas Biossensoriais/métodos , Corantes Fluorescentes , Fenômenos Magnéticos , RNA Polimerase Dependente de RNA
12.
J Immunol Methods ; 528: 113667, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574803

RESUMO

Chimeric antigen receptor (CAR) redirected T cells are successfully employed in the combat against several hematological malignancies, however, are often compromised by low transduction rates making refinement of the CAR T cell products necessary. Here, we report a broadly applicable enrichment protocol relying on marking CAR T cells with an anti-glycine4-serine (G4S) linker antibody followed by magnetic activated cell sorting (MACS). The protocol is broadly applicable since the G4S peptide is an integral part of the vast majority of CARs as it links the VH and VL recognition domains. We demonstrate the feasibility by using the canonical second generation CARs specific for CEA and Her2, respectively, obtaining highly purified CAR T cell products in a one-step procedure without impairing cell viability. The protocol is also applicable to a dual specific CAR (tandem CAR). Except for CD39, T cell activation/exhaustion markers were not upregulated after separation. Purified CAR T cells retained their functionality with respect to antigen-specific cytokine secretion, cytotoxicity, and the capacity to proliferate and eliminate cognate tumor cells upon repetitive stimulation. Collectively, the one-step protocol for purifying CAR T cells extends the toolbox for preclinical research and specifically for clinical CAR T cell manufacturing.


Assuntos
Receptores de Antígenos Quiméricos , Linfócitos T , Citotoxicidade Imunológica , Separação Celular , Fenômenos Magnéticos , Imunoterapia Adotiva/métodos
14.
Int J Mol Sci ; 25(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38612438

RESUMO

Magnetic activated cell sorting (MACS) is a well-known sperm selection technique, which is able to remove apoptotic spermatozoa from semen samples using the classic annexinV based method. Leukocytes and erythrocytes in semen samples or in testicular tissue processed for in vitro fertilization (IVF) could exert detrimental effects on sperm. In the current study, we rethought the aforementioned technique and used magnetic microbeads conjugated with anti-CD45/CD235a antibodies to eliminate contaminating leukocytes and erythrocytes from leukocytospermic semen samples and testicular tissue samples gained via testicular sperm extraction (TESE). With this technique, a 15.7- and a 30.8-fold reduction could be achieved in the ratio of leukocytes in semen and in the number of erythrocytes in TESE samples, respectively. Our results show that MACS is a method worth to reconsider, with more potential alternative applications. Investigations to find molecules labeling high-quality sperm population and the development of positive selection procedures based on these might be a direction of future research.


Assuntos
Líquidos Corporais , Sêmen , Masculino , Humanos , Secreções Corporais , Espermatozoides , Fenômenos Magnéticos
15.
HLA ; 103(4): e15490, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634568

RESUMO

The presence of multiple donor-specific antibodies (DSAs) targeting HLA antigens poses a challenge to transplantation. Various techniques, including the use of recombinant cell lines and crossmatch cells have been developed to isolate DSAs. To simplify the extraction of HLA-specific DSAs from complex sera, we introduced magnetic beads with single HLA specificity (MagSort). Sera were treated with MagSort, allowing HLA-specific antibodies to bind to the beads, and these specific antibodies were subsequently eluted. MagSort beads, coated with 59 different HLA variants, underwent testing through 1329 adsorption/elution processes, demonstrating their effectiveness and specificity in adsorbing and eluting HLA-specific antibodies. The MagSort method proves comparable to the cell method, showing similar isolated antibody binding patterns. The isolated antibody binding patterns from MagSort reveal both known eplets and unknown patterns, suggesting its utility for eplet discovery. Additionally, MagSort proved effective in extracting signals for flow cytometry cross-matching, offering a means to assess the binding capability of isolated antibodies against specific donor cells.


Assuntos
Anticorpos , Antígenos HLA , Humanos , Alelos , Teste de Histocompatibilidade/métodos , Fenômenos Magnéticos , Isoanticorpos , Rejeição de Enxerto
16.
Anal Chim Acta ; 1304: 342554, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637038

RESUMO

BACKGROUND: Many proteins with thiol groups can bind with trivalent arsenic which are termed as arsenic binding proteins, thus change their physiological functions. Therefore, it is vital to analyze the arsenic binding proteins in cells. The Pull-Down strategy based on biotinylated phenylarsenic acid (Bio-PAO(III)) probes is an effective way for analysis of arsenic binding proteins. In this strategy, streptavidin magnetic beads (SA-MBs) was applied to capture the arsenic binding proteins conjugating with Bio-PAO(III) probe. However, strong interaction between SA and biotin makes the elution of arsenic binding proteins not easy. RESULTS: We developed a novel affinity separation strategy to address the challenge of eluting arsenic binding proteins, a key issue with the existing Bio-PAO(III) Pull-Down method. By employing magnetic beads modified with Nα-Bis(carboxymethyl)-l-lysine (NTA-Lys), polyhistidine-tag (His6-Tag), and SA (MB-NTA(Ni)-His6-SA), we established a more efficient purification process. This innovative approach enables selective capture of arsenic binding proteins in HepG2 cells labeled by Bio-PAO(III) probes, facilitating gentle digestion by trypsin for precise identification through capillary high performance liquid chromatography (Cap HPLC)-electrospray ionization (ESI)-tandem mass spectrometry (MS/MS). What is more, the magnetic beads can be regenerated by using imidazole as the eluent, and the obtained MB-NTA(Ni) can be reloaded with His6-SA for next use. Our method successfully identified 41 arsenic binding proteins, including those involved in cytoskeletal structure, heat shock response, transcriptional regulation, DNA damage repair, redox state regulation, mitochondrial dehydrogenase function, and protein synthesis and structure. SIGNIFICANCE: This work contributes to a more comprehensive understanding of the toxic mechanisms of arsenic, potentially providing valuable insights for the prevention or treatment of arsenic-related diseases.


Assuntos
Arsênio , Arsênio/análise , Proteínas de Transporte , Espectrometria de Massas em Tandem , Histidina/química , Fenômenos Magnéticos
17.
Bull Environ Contam Toxicol ; 112(4): 64, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38622342

RESUMO

A fast and simple dispersive solid phase extraction method is described for nitrophenols determination in water samples by using gas chromatography-nitrogen phosphorous detector. Firstly, the Poly(amidoamine) grafted Fe3O4 magnetic nanoparticles were synthesized in different generations by successive addition of butyl acrylate and ethylenediamine. After characterization, the prepared dendrimer was utilized as an adsorbent for magnetic solid phase extraction of 2-nitrophenol, 3-nitrophenol, and 4-nitrophenol to benefit large number of surface amine interaction sites. The effects of the different parameters influencing the sample preparation efficiency were investigated. The proposed method showed linearity in the ranges of 0.04-700 and 0.05-700 µg/dm3 for nitrophenols. The obtained limits of detection and quantification under optimized conditions were 0.01-0.02 and 0.04-0.05 µg/dm3, respectively. The relative standard deviations (n = 5) were less than 3.8% (at 10 µg/dm3). Moreover, the calculated enrichment factors were above 200. In addition, the relative recoveries for a spiked river water sample were satisfactory.


Assuntos
Dendrímeros , Poliaminas , Água , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Nitrofenóis , Limite de Detecção
18.
J Gastrointest Surg ; 28(4): 394-401, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38583889

RESUMO

BACKGROUND: Endoscopic submucosal dissection (ESD) has been recommended as the first-line treatment for early gastric cancer (EGC). However, poor visualization of the operative field increases both the procedure time and the risk of complications, especially for large and difficult lesions. We introduced a novel technique, magnetic anchor-guided ESD (MAG-ESD) and compared it with conventional ESD (C-ESD) for the treatment of large EGCs in terms of efficacy, safety, and advantages. METHODS: Patients with large EGCs who underwent MAG-ESD or C-ESD at the First Affiliated Hospital of Xi'an Jiaotong University from March 2020 to March 2022 were retrospectively enrolled in this study. The patients in the MAG-ESD cohort were matched to those in the C-ESD cohort using propensity score-based matching. The operation time, submucosal dissection time, complete resection status, magnetic anchor, adverse event rate, and tumor recurrence rate were evaluated. RESULTS: Twenty-two patients who underwent MAG-ESD were ultimately matched to those who underwent C-ESD. The median operation time of MAG-ESD and C-ESD was 43 minutes (IQR, 35.2-49.5) and 50.5 minutes (IQR, 42.0-76.0), respectively, among which the submucosal dissection time was 7.6 minutes (IQR, 5.2-10.4) and 14.8 minutes (IQR, 10.8-19.6), respectively. The operation time of MAG-ESD was shorter than that of C-ESD, especially the submucosal dissection time (P < .05). There was a lower incidence of adverse events associated with MAG-ESD (P < .05) when magnetic anchors were successfully placed and retrieved. CONCLUSION: MAG-ESD is feasible, effective, safe, and simple for the treatment of large EGCs at different sites and has a high anchor success rate, which could shorten the operation time and reduce the adverse event rate.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Estudos de Coortes , Resultado do Tratamento , Recidiva Local de Neoplasia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Fenômenos Magnéticos
19.
Sci Rep ; 14(1): 7907, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575669

RESUMO

Vesicovaginal fistula lacks a standard, established animal model, making surgical innovations for this condition challenging. Herein, we aimed to non-surgically establish vesicovaginal fistula using the magnetic compression technique, and the feasibility of this method was explored using eight female Beagle dogs as model animals. In these dogs, cylindrical daughter and parent magnets were implanted into the bladder and vagina, respectively, after anesthesia, and the positions of these magnets were adjusted under X-ray supervision to make them attract each other, thus forming the structure of daughter magnet-bladder wall-vaginal wall-parent magnet. Operation time and collateral damage were recorded. The experimental animals were euthanized 2 weeks postoperatively, and the vesicovaginal fistula gross specimens were obtained. The size of the fistula was measured. Vesicovaginal fistula was observed by naked eye and under a light microscope. Magnet placement was successful in all dogs, and remained in the established position for the reminder of the experiment. The average operation time was 14.38 min ± 1.66 min (range, 12-17 min). The dogs were generally in good condition postoperatively and were voiding normally, with no complications like bleeding and urine retention. The magnets were removed from the vagina after euthanasia. The vesicovaginal fistula was successfully established according to gross observation, and the fistula diameters were 4.50-6.24 mm. Histological observation revealed that the bladder mucosa and vaginal mucosa were in close contact on the internal surface of the fistula. Taken together, magnetic compression technique is a simple and feasible method to establish an animal model of vesicovaginal fistula using Beagle dogs. This model can help clinicians study new surgical techniques and practice innovative approaches for treating vesicovaginal fistula.


Assuntos
Fístula Vesicovaginal , Humanos , Cães , Animais , Feminino , Fístula Vesicovaginal/cirurgia , Fístula Vesicovaginal/etiologia , Bexiga Urinária/cirurgia , Vagina/cirurgia , Magnetismo , Fenômenos Magnéticos
20.
Methods Enzymol ; 694: 109-135, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38492948

RESUMO

In neuroscience, understanding the mechanics of synapses, especially the function of force-sensitive proteins at the molecular level, is essential. This need emphasizes the importance of precise measurement of synaptic protein interactions. Addressing this, we introduce high-resolution magnetic tweezers (MT) as a novel method to probe the mechanics of synapse-related proteins with high precision. We demonstrate this technique through studying SNARE-complexin interactions, crucial for synaptic transmission, showcasing its capability to apply specific forces to individual molecules. Our results reveal that high-resolution MT provides in-depth insights into the stability and dynamic transitions of synaptic protein complexes. This method is a significant advancement in synapse biology, offering a new tool for researchers to investigate the impact of mechanical forces on synaptic functions and their implications for neurological disorders.


Assuntos
Proteínas SNARE , Sinapses , Proteínas SNARE/metabolismo , Transmissão Sináptica , Fenômenos Magnéticos , Proteínas Adaptadoras de Transporte Vesicular/metabolismo
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