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1.
Nature ; 627(8004): 522-527, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38509277

RESUMEN

Topological whirls or 'textures' of spins such as magnetic skyrmions represent the smallest realizable emergent magnetic entities1-5. They hold considerable promise as robust, nanometre-scale, mobile bits for sustainable computing6-8. A longstanding roadblock to unleashing their potential is the absence of a device enabling deterministic electrical readout of individual spin textures9,10. Here we present the wafer-scale realization of a nanoscale chiral magnetic tunnel junction (MTJ) hosting a single, ambient skyrmion. Using a suite of electrical and multimodal imaging techniques, we show that the MTJ nucleates skyrmions of fixed polarity, whose large readout signal-20-70% relative to uniformly magnetized states-corresponds directly to skyrmion size. The MTJ exploits complementary nucleation mechanisms to stabilize distinctly sized skyrmions at zero field, thereby realizing three non-volatile electrical states. Crucially, it can electrically write and delete skyrmions to both uniform states with switching energies 1,000 times lower than the state of the art. Here, the applied voltage emulates a magnetic field and, in contrast to conventional MTJs, it reshapes both the energetics and kinetics of the switching transition, enabling deterministic bidirectional switching. Our stack platform enables large readout and efficient switching, and is compatible with lateral manipulation of skyrmionic bits, providing the much-anticipated backbone for all-electrical skyrmionic device architectures9,10. Its wafer-scale realizability provides a springboard to harness chiral spin textures for multibit memory and unconventional computing8,11.

2.
Antonie Van Leeuwenhoek ; 117(1): 101, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008162

RESUMEN

Two novel Gram-stain-negative, aerobic, and non-motile strains, designated FZY0004T and YYF002T, were isolated from an agar-degrading co-culture, which was obtained from seawater of the intertidal zone of Yancheng City, the Yellow Sea of China. Strain FZY0004T optimally grew at 28 °C, pH 7.0, and 2-6% NaCl, while strain YYF002T optimally grew at 28 °C, pH 7.5, and 2-4% NaCl. Strain FZY0004T possessed Q-9 as the major respiratory quinone, and its major fatty acids (> 10%) were summed feature 8 (C18:1 ω7c), C16:0, and summed feature 3 (C16:1 ω7c/C16:1 ω6c). The polar lipids identified in strain FZY0004T were phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and several unidentified phospholipids (PL) and lipids (L). On the other hand, strain YYF002T had MK-6 as the predominant respiratory quinone and its major fatty acids consisted of iso-C15:0, iso-C15:1 G, and iso-C15:0 3-OH. The polar lipids identified in strain YYF002T were aminolipid (AL), PE, and several unidentified lipids. Strain FZY0004T shared 99.5% 16S rRNA gene sequence similarity and 90.1% average nucleotide identity (ANI) with T. povalilytica Zumi 95T, and strain YYF002T shared 99.2% 16S rRNA gene sequence similarity and 88.2% ANI with W. poriferorum JCM 12885T. The genomic DNA G + C contents of strains FZY0004T and YYF002T were 54.5% and 33.5%, respectively. The phylogenetic, phenotypic, and physiological characteristics permitted the distinction of the two strains from their neighbors, and we thus propose the names Thalassospira aquimaris sp. nov. (type strain FZY0004T = JCM 35895T = MCCC 1K08380T) and Winogradskyella marincola sp. nov. (type strain YYF002T = JCM 35950T = MCCC 1K08382T).


Asunto(s)
Agar , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S , Agua de Mar , ARN Ribosómico 16S/genética , Agua de Mar/microbiología , ADN Bacteriano/genética , Agar/metabolismo , Ácidos Grasos/metabolismo , Composición de Base , Técnicas de Tipificación Bacteriana , China , Fosfolípidos/metabolismo , Técnicas de Cocultivo , Análisis de Secuencia de ADN
3.
Nano Lett ; 21(3): 1253-1259, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33481614

RESUMEN

Controllable writing and deleting of nanoscale magnetic skyrmions are key requirements for their use as information carriers for next-generation memory and computing technologies. While several schemes have been proposed, they require complex fabrication techniques or precisely tailored electrical inputs, which limits their long-term scalability. Here, we demonstrate an alternative approach for writing and deleting skyrmions using conventional electrical pulses within a simple, two-terminal wire geometry. X-ray microscopy experiments and micromagnetic simulations establish the observed skyrmion creation and annihilation as arising from Joule heating and Oersted field effects of the current pulses, respectively. The unique characteristics of these writing and deleting schemes, such as spatial and temporal selectivity, together with the simplicity of the two-terminal device architecture, provide a flexible and scalable route to the viable applications of skyrmions.

4.
Mikrochim Acta ; 186(2): 109, 2019 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-30637509

RESUMEN

A rapid and ultrasensitive method is described for the detection of staphylococcal enterotoxin B (SEB). It is based on the formation of a dendritic DNA superstructure by integrating (a) target-induced triggering of DNA release with (b) signal amplification by a hybridization chain reaction. Partially complementary pairing of aptamer and trigger DNA forms a duplex structure. The capture DNA is then placed on the surface of a gold electrode through gold-thiol chemistry. In the presence of SEB, the aptamer-target conjugate is compelled to form. This causes the release of trigger DNA owing to a strong competition with SEB. The trigger DNA is subsequently hybridized with the partial complementary sequences of the capture DNA to trigger HCR with three auxiliary DNA sequances (referred to as H1, H2, H3). Finally, the dendritic DNA superstructure is bound to hexaammineruthenium(III) cation by electrostatic adsorption and assembled onto the modified gold electrode. This produces an amplified electrochemical signal that is measured by chronocoulometry. Under optimal conditions, the charge difference increases linearly with the logarithm of the SEB concentrations in the range from 5 pg·mL-1 to 100 ng·mL-1 with a detection limit as low as 3 pg·mL-1 (at S/N = 3). Graphical abstract An electrochemical switching strategy is presented for the sensitive detection of Staphylococcus enterotoxin B based on target-triggered assembly of dendritic nucleic acid nanostructures.


Asunto(s)
Aptámeros de Nucleótidos/química , Colorimetría/instrumentación , ADN/química , Enterotoxinas/análisis , Oro/química , Nanoestructuras/química , Adsorción , Animales , Color , Electrodos , Límite de Detección , Leche/química , Modelos Moleculares , Conformación de Ácido Nucleico , Hibridación de Ácido Nucleico , Compuestos de Rutenio/química , Compuestos de Sulfhidrilo/química
5.
Mikrochim Acta ; 185(10): 460, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30219956

RESUMEN

An electrochemical switching strategy is presented for the sensitive determination of Staphylococcus enterotoxin B (SEB). It is based on the use of DNA triangular pyramid frustum nanostructure (TPFDNA) consisting of (a) three thiolated probes, (b) one auxiliary probe, and (c) an aptamer against SEB. The TPFDNA was assembled on the gold electrode, with the SEB aptamer designed on top of the TPFDNA. The electron transfer to hexacyanoferrate acting as an electrochemical probe is strongly inhibited in the TPFDNA-modified electrode. This is assumed to be due to the formation of a 3D TPFDNA structure that limits access of hexacyanoferrate to the electrode. Therefore, the Faradaic impedance is large. However, in the presence of SEB, it will bind to the aptamer and dehybridize the hybrid formed between aptamer and its complementary sequence. As a result, the TPFDNA nanostructure changes to an equilateral triangle DNA nanostructure. This results in a more efficient electron transfer and a smaller Faradaic impedance. The method has a detection limit of 0.17 ng mL-1 of SEB (at an S/N of 3) and a dynamic range that covers the 0.2-1000 ng mL-1 concentration range. The applicability and reliability of the method was demonstrated by anayzing (spiked) milk samples, and the results were compared to those obtained with an ELISA kit. The relative standard deviations between the two methods range between -6.59 and 9.33%. Graphical abstract An electrochemical switching strategy is presented for the sensitive detection of Staphylococcus enterotoxin B based on 3D DNA structure conversion of nanostructure from triangular pyramid frustum to equilateral triangle.


Asunto(s)
Técnicas Biosensibles/métodos , Sondas de ADN/química , Electroquímica/métodos , Enterotoxinas/análisis , Nanoestructuras/química , Conformación de Ácido Nucleico , Animales , Secuencia de Bases , Impedancia Eléctrica , Electrodos , Transporte de Electrón , Enterotoxinas/química , Oro/química , Leche/química
6.
Bioprocess Biosyst Eng ; 37(9): 1849-58, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24584361

RESUMEN

The optimal temperature for the microbial polysaccharide fermentation is no higher than 30 °C, which is economically undesirable due to additional cooling cost. To solve this problem in the case of welan gum production, we obtained the high-temperature-tolerant-producing strain, Sphingomonas sp. HT-1 by atmospheric and room-temperature plasma-induced mutation. Using HT-1, we obtained a concentration and 1 % aqueous viscosity of 26.8 ± 0.34 g/L and 3.50 ± 0.05 Pa s at a comparatively higher optimal temperature (37 °C). HT-1 was further characterized to understand the mechanism by which these properties are improved. Results indicated that high yield could be attributed to the following: (1) enhanced intracellular synthesis, demonstrated by an increase in the activities of key enzymes, and (2) accelerated cross-membrane substrate uptake and product secretion, indicated by improved membrane fluidity and permeability. Temperature tolerance could be attributed to the overexpression of the investigated heat shock proteins and oxidative stress proteins.


Asunto(s)
Calor , Mutación , Polisacáridos Bacterianos/biosíntesis , Sphingomonas/aislamiento & purificación , Fermentación , Microscopía Electrónica de Transmisión , Estrés Oxidativo , Reacción en Cadena de la Polimerasa , Sphingomonas/genética
7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(5): 554-5, 561, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-24941843

RESUMEN

OBJECTIVE: To observe the therapeutic efficacy of Dangfei Liganning Tablet (DLT) in the treatment of antipsychotics induced mild hepatic damage. METHODS: Totally 80 mental inpatients with antipsychotics induced mild liver injury were randomly assigned to two groups, the treatment group (40 cases) and the control group (40 cases). Patients in the treatment group took DLT, two tablets each time, three times per day, while those in the control group took Liver-protecting Tablet (LT), four tablets each time, three times per day. The treatment course was 4 weeks for all. Changes of glutamic-pyruvic transaminase (ALT) and glutamic-oxalacetic transaminase (AST) were observed before treatment, week 1, 2, and 4 after treatment. The therapeutic efficacy was compared between the two groups. RESULTS: Compared with the former time point, ALT and AST gradually decreased in the two groups at week 1, 2, and 4 (P <0. 05). The cured rate was 72. 5% and the total effective rate was 97. 5% in the treatment group. They were 62. 5% and 90. 0% respectively in the control group. There was no statistical difference in the two indices between the two group (P >0.05). No obvious adverse reaction occurred in the two groups. CONCLUSION: DLT could treat antipsychotics induced mild hepatic damage in a safe and effective way.


Asunto(s)
Antipsicóticos/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Sustancias Protectoras/uso terapéutico , Alanina Transaminasa/metabolismo , Medicamentos Herbarios Chinos/administración & dosificación , Humanos , Hígado/metabolismo , Sustancias Protectoras/administración & dosificación , Comprimidos/uso terapéutico
8.
Heliyon ; 10(12): e33085, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38988517

RESUMEN

Background: Blood metabolites serve as pivotal indicators in identifying and predicting the course of rheumatoid arthritis (RA). However, empirical substantiation of a direct causal link between these serum biomarkers and the development of RA is still lacking comprehensive support. Method: In pursuit of a thorough exploration of the causal links between circulating blood metabolites and RA, we deployed a two-sample Mendelian randomization (MR) approach during our initial investigative phase. This method was utilized to examine the potential connections between 249 distinct circulating metabolites and the prevalence of RA. In the validation phase, we conducted replication analyses with a new metabolic dataset consisting of 123 metabolites. Furthermore, we employed the Mendelian randomization based on Bayesian model averaging (MR-BMA) technique to pinpoint key metabolic characteristics that have significant causal implications. Results: In our primary analysis, we found that acetate, acetoacetate and pyruvate exhibited a consistent protective causal association with rheumatoid arthritis, while lactate demonstrated a positive correlation with rheumatoid arthritis risk. It is also noteworthy that a substantial subset of traits related to both saturated and unsaturated fatty acids showed causal influences. Subsequent secondary analyses substantiated these observations, revealing that traits associated with the average number of methylene groups in a fatty acid chain exhibited protective effects. Ultimately, our MR-BMA analyses unveiled that the ratio of polyunsaturated fatty acids (PUFAs) to total fatty acids assumes a paramount role in increasing the susceptibility to rheumatoid arthritis. Conclusions: By employing systemic MR analyses, our study has successfully generated an all-encompassing atlas elucidating the intricate connections between circulating metabolites and the susceptibility to rheumatoid arthritis. Our results indicate the high unsaturation degree is a dominant risk factors correlated with rheumatoid arthritis.

9.
ACS Appl Mater Interfaces ; 16(1): 1025-1032, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38156820

RESUMEN

The interplay of magnetic interactions in chiral multilayer films gives rise to nanoscale topological spin textures that form attractive elements for next-generation computing. Quantifying these interactions requires several specialized, time-consuming, and resource-intensive experimental techniques. Imaging of ambient domain configurations presents a promising avenue for high-throughput extraction of parent magnetic interactions. Here, we present a machine learning (ML)-based approach to simultaneously determine the key magnetic interactions─symmetric exchange, chiral exchange, and anisotropy─governing the chiral domain phenomenology in multilayers, using a single binarized image of domain configurations. Our convolutional neural network model, trained and validated on over 10,000 domain images, achieved R2 > 0.85 in predicting the parameters and independently learned the physical interdependencies between magnetic parameters. When applied to microscopy data acquired across samples, our model-predicted parameter trends are consistent with those of independent experimental measurements. These results establish ML-driven techniques as valuable, high-throughput complements to conventional determination of magnetic interactions and serve to accelerate materials and device development for nanoscale electronics.

10.
Expert Rev Clin Pharmacol ; : 1-18, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39269366

RESUMEN

BACKGROUND: Pulmonary hypertension (PH) is a life-threatening condition with high mortality, categorized into Group 1-5 by distinct etiologies. Fasudil, a potent vasodilator targeting RhoA/Rho kinase pathway, holds promise for diverse PH pathologies. However, a systematic evaluation of its clinical benefits remains elusive. METHODS: We conducted a systematic search in several databases. Meta-analysis using odds ratio and mean difference was performed, with an assessment of studies' quality and pooled evidences. RESULTS: Inclusion of 3269 Group-3 PH patients demonstrated that Fasudil increased effective events, forced expiratory volume in one second (FEV1), 6-minute walking distance (6MWD) and arterial partial pressure of oxygen (PaO2), and decreased mean pulmonary artery pressure (mPAP) and pulmonary artery systolic pressure (PASP); Inclusion of 197 Group-2 PH patients suggested that Fasudil increased 6MWD and PaO2, and decreased PASP. Subgroup analysis revealed no significant difference between 30 and 60 mg/day dosages of Fasudil, while administration durations and methods might affect its effectiveness in treating Group-3 PH patients. CONCLUSIONS: Our study favors the beneficial effects of Fasudil by enhancing FEV1, 6MWD and PaO2, and reducing mPAP and PASP on Group-3 PH patients, suggesting Fasudil as a viable treatment option and highlighting the need for further studies to inform healthcare policies. PROTOCOL REGISTRATION: www.crd.york.ac.uk/prospero identifier is CRD42022308947.

11.
Adv Sci (Weinh) ; 9(6): e2103978, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34978165

RESUMEN

Magnetic skyrmions are topologically wound nanoscale textures of spins whose ambient stability and electrical manipulation in multilayer films have led to an explosion of research activities. While past efforts focused predominantly on isolated skyrmions, recently ensembles of chiral spin textures, consisting of skyrmions and magnetic stripes, are shown to possess rich interactions with potential for device applications. However, several fundamental aspects of chiral spin texture phenomenology remain to be elucidated, including their domain wall (DW) structure, thermodynamic stability, and morphological transitions. Here the evolution of these textural characteristics are unveiled on a tunable multilayer platform-wherein chiral interactions governing spin texture energetics can be widely varied-using a combination of full-field electron and soft X-ray microscopies with numerical simulations. With increasing chiral interactions, the emergence of Néel helicity, followed by a marked reduction in domain compressibility, and finally a transformation in the skyrmion formation mechanism are demonstrated. Together with an analytical model, these experiments establish a comprehensive microscopic framework for investigating and tailoring chiral spin texture character in multilayer films.

12.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): m1294-5, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22058883

RESUMEN

In the title one-dimensional coordination polymer, {[Eu(C(9)H(4)N(2)O(4))(C(9)H(5)N(2)O(4))(H(2)O)(3)]·2H(2)O}(n), one of the 1H-benzimidazole-5,6-dicarboxyl-ate (Hbdc) ligands is protonated at the imidazole group (H(2)bdc). The Eu(III) ion is eight-coordinated by two O atoms from two Hbdc ligands, three O atoms from two H(2)bdc ligands and three water mol-ecules, showing a distorted square-anti-prismatic geometry. The Eu(III) ions are bridged by the carboxyl-ate groups of the Hbdc and H(2)bdc ligands, forming a chain along [110], with an Eu⋯Eu separation of 5.4594 (3) Å. These chains are further connected by inter-molecular O-H⋯O, N-H⋯O and N-H⋯N hydrogen bonds, as well as π-π inter-actions between the imidazole and benzene rings [centroid-centroid distances = 3.558 (3), 3.906 (2), 3.397 (3), 3.796 (2) and 3.898 (2) Å], into a three-dimensional supra-molecular network.

13.
Front Endocrinol (Lausanne) ; 12: 773342, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992579

RESUMEN

Objective: The influence of diabetes on mortality among patients with non-alcoholic fatty liver disease (NAFLD) in the general population has not been extensively studied. This study aimed to determine the relationship between diabetes and all-cause and cardiovascular mortality in patients with hepatic ultrasound-confirmed NAFLD using data from the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994. Methods: Data from 4,037 adult individuals with NAFLD from the NHANES III and mortality outcomes linked to National Death Index records through December 31, 2015, were included. Cox proportional hazards models were used to calculate the hazard ratio (HR) and corresponding 95% CI for mortality from all causes and cardiovascular disease after adjusting for multiple variables. Results: Among 4,037 subjects with NAFLD (55.9% female), 483 had diabetes at baseline. During a median follow-up of 22.1 years, 1,517 (11.5%) died, including 332 (8.22%) from cardiovascular causes. Diabetes was associated with increased all-cause (HR 3.02 [95% CI 2.67-3.41]) and cardiovascular (HR 3.36 [95% CI 2.61-4.32]) mortality in an unadjusted multivariable Cox regression model. The association remained statistically significant after adjusting for a range of potential confounders (HR 2.20 [95% CI 1.90-2.55] for all-cause mortality and HR 2.47 [95% CI 1.81-3.37] for cardiovascular mortality). An additional stratified analysis did not reveal significantly altered results. Conclusion: Diabetes was associated with all-cause and cardiovascular mortality in patients with NAFLD. This link could be further characterized in future studies assessing the degree of glycemic control and its relationship with mortality in patients with diabetes and NAFLD.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Adulto , Anciano , Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades Cardiovasculares/mortalidad , Causas de Muerte , Estudios Transversales , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Diabetes Mellitus Tipo 2/mortalidad , Femenino , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/mortalidad , Estudios Prospectivos , Tasa de Supervivencia , Ultrasonografía
14.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1482, 2010 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-21588897

RESUMEN

In the title coordination polymer, [Ag(C(14)H(8)NO(2))](n), the Ag(I) cation is coordinated by two O atoms and one N atom from two symmetry-related acridine-9-carboxyl-ate ligands in a distorted trigonal-planar geometry. The metal atoms are connected by the ligands to form chains running parallel to the b axis. π-π stacking inter-actions [centroid-to-centroid distances 3.757 (2)-3.820 (2) Å] and weak Ag⋯O inter-actions further link the chains to form a layer network parallel to the ab plane. The Ag(I) cation is disordered over two positions, with refined site-occupancy factors of 0.73 (3):0.27 (3).

15.
Talanta ; 210: 120677, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31987188

RESUMEN

The level of miRNA-21, miRNA-122, and miRNA-223 are always elevated when liver cancer is present at an early stage. In this paper, a novel assay to simultaneous detect miRNA-21, miRNA-122, and miRNA-223 was proposed based on DNA tetrahedron nanotags and fluorescence resonance energy transfer (FRET), which used a single laser stimulate wavelengh from one nucleic acid stain TOTO-1 to three diverse organic dyes (Cy3, Cy3.5, Cy5). In brief, a DNA tetrahedral nanostructure (DTN) was designed with three adaptor oligos on its vertices. TOTO-1, as a fluorescent donor, can imbed into native nucleic acid backbone of DTN. Three organic dye-functionalized strands (FRET oligos) are fluorescent receptors. In the presence of target miRNAs, they can be hybridized with FRET oligos and adaptor oligos on the vertices of DTN and the stable DNA tetrahedron nanotags are formed. As a result, the confinement of TOTO-1 is in close proximity to three fluorescence dyes, the FRET between TOTO-1 and three fluorescence dyes is generate efficiently in DNA tetrahedron nanotags. Point-of-care clinical applicability is demonstrated by sensitive multiplexed quantification of three miRNAs in 10% human serum samples.


Asunto(s)
ADN de Neoplasias/química , Transferencia Resonante de Energía de Fluorescencia , Neoplasias Hepáticas/química , MicroARNs/sangre , Nanopartículas/química , Carbocianinas/química , Colorantes/química , Humanos , Neoplasias Hepáticas/diagnóstico por imagen
16.
J Biomed Nanotechnol ; 16(1): 54-64, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31996285

RESUMEN

Luteolin (Lut) is a natural flavonoid mainly extracted from vegetables and fruits. Lut shows great anti-tumor potential in many malignant cancers, which are hindered by poor water solubility and low bioavailability. Peritoneal metastasis is a challenge for colorectal cancer treatment, usually indicating unfavorable prognosis of patients. Methoxy poly(ethylene glycol)-poly(ε-caprolactone) micelles containing Luteolin (Lut-M) and thermosensitive Pluronic®F127 coated Lut-M (Lut-M-F127) were synthesized and applied in the local therapy of colorectal cancer. Drug release study of Lut-M-F127 and Lut-M suggested extended drug release, and the release of Lut from Lut-M-F127 was slower than Lut-M. It was also proved that Lut-M-F127 could transit from solution to gel at body temperature. Moreover, both Lut-Free and Lut-M micelles were capable of inducing tumor cell apoptosis and reducing cell viability in vitro. Our results further demonstrated the therapeutic effect of Lut-M-F127 treatment was much better than that of Lut-M treatment in vivo. Lut-M-F127 has shown strong ability to promote tumor apoptosis, suppress tumor proliferation and block tumor angiogenesis. In summary, Lut-M-F127 formulation may be a very promising treatment option for peritoneal metastasis in colorectal cancer in the future.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Peritoneales , Línea Celular Tumoral , Humanos , Luteolina , Micelas
17.
Biosens Bioelectron ; 150: 111873, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31748193

RESUMEN

In order to avoid the occurrence of false positives and false negatives caused by improper pretreatment during the detection of aflatoxin B1 by enzyme linked immunosorbent assay (ELISA). In this paper, we developed a screen printed bipolar electrode (BPE) for sensitive electrochemiluminescence (ECL) detection of aflatoxin B1 in agricultural products. The sensor uses a cathode of closed BPE as a functional sensing interface and an anode as a signal collection interface. In this way, the analyte does not need to participate in the ECL reaction of the anode. It avoids direct contact of photoactive molecules with complex reaction systems and greatly broadens the range of applications for ECL. After mixing the test sample with a known fixed concentration of horseradish peroxidase-labeled AFB1 (HRP-AFB1), they compete for binding to monoclonal antibodies. HRP catalyzes the polymerization of aniline to form polyaniline (PANI). Thereby causing a change in the oxidation-reduction potential and the ECL intensity in the electrochemical system, and then achieve the purpose of detecting the AFB1 concentration in the sample. As a result, the sensor has a good analytical performance for AFB1 with a linear range of 0.1-100 ng mL-1 and a detection limit of 0.033 ng mL-1. The sensor avoids the direct contact between the reaction system and the signal measurement system. In recovery experiment for six grains, the results demonstrate that the recovery rate and accuracy of this sensor is better than that of ELISA. This method provides a new idea for the detection of other mycotoxins in grains.


Asunto(s)
Aflatoxina B1/aislamiento & purificación , Técnicas Biosensibles , Técnicas Electroquímicas , Aflatoxina B1/química , Productos Agrícolas/química , Electrodos , Mediciones Luminiscentes
18.
ACS Nano ; 14(2): 2172-2182, 2020 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-31990525

RESUMEN

Efficient protein delivery into the target cell is highly desirable for protein therapeutics. Current approaches for protein delivery commonly suffer from low-loading protein capacity, poor specificity for target cells, and invisible protein release. Herein, we report a protein@inorganic nanodumpling (ND) system as an intracellular protein delivery platform. Similar to a traditional Chinese food, the dumpling, ND consists of a protein complex "filling" formed by metal-ion-directed self-assembly of protein cargos fused to histidine-rich green fluorescent proteins (H39GFPs), which are further encapsulated by an external surface "wrapper" of manganese dioxide (MnO2) via in situ biomineralization. This ND structure allows for a high loading capacity (>63 wt %) for protein cargos with enhanced stability. NDs can be targeted and internalized into cancer cells specifically through folic acid receptors by surface-tailored folic acid. The protein cargo release is in a bistimuli-responsive manner, triggered by an either reductive or acidic intracellular microenvironment. Moreover, the MnO2 nanowrapper is an efficient fluorescence quencher for inner fused GFPs and also a "switch-on" magnetic resonance imaging (MRI) agent via triggered release of Mn2+ ions, which enables activatable fluorescence/MRI bimodal imaging of protein release. Finally, the ND is highly potent and specific to deliver functional protein ribonuclease A (RNase A) into cultured target cells and the tumor site in a xenografted mouse model, eliminating the tumor cells with high therapeutic efficacy. Our approach provides a promising alternative to advance protein-based cancer therapeutics.


Asunto(s)
Sistemas de Liberación de Medicamentos , Fluorescencia , Proteínas Fluorescentes Verdes/química , Imagen por Resonancia Magnética , Compuestos de Manganeso/química , Nanopartículas/química , Óxidos/química , Animales , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Ratones , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/terapia , Imagen Óptica , Tamaño de la Partícula , Ribonucleasa Pancreática/química , Ribonucleasa Pancreática/metabolismo , Propiedades de Superficie , Células Tumorales Cultivadas
19.
Chem Commun (Camb) ; 54(56): 7806-7809, 2018 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-29946615

RESUMEN

A charge designable and tunable green fluorescent protein (GFP)-based protein delivery strategy was proposed. The acquired His29GFP selectively permeates the cell membrane at a target pH of 6.5 and escapes from the endosome efficiently. The delivered RNase A caused substantial mRNA degradation in HeLa cells, and proliferation inhibition in different cell lines and a 3D tumor model at pH 6.5.

20.
Medicine (Baltimore) ; 97(51): e13775, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30572531

RESUMEN

BACKGROUND: Different antivascular endothelial growth factor (VEGF) monotherapy regimens and photodynamic therapy (PDT) combined with anti-VEGF therapy are available for patients with polypoidal choroidal vasculopathy (PCV). However, the comparative efficacy and safety of different anti-VEGF monotherapy regimens and combined therapy with PDT and anti-VEGF remains unknown. The aim of our study is to evaluate the efficacy and safety of anti-VEGF monotherapies and combined therapy in patients with PCV. METHODS: We will systematically search PubMed, Embase, and the Cochrane library for eligible studies. The Cochrane Collaboration's tool for assessing the risk of bias in a randomized trial and the ROBINS-I tool will be used to assess the risk of bias in the included studies. The primary outcome is the mean change in best corrected visual acuity from baseline. The secondary outcomes are the mean change in central retinal thickness from baseline and the number of serious adverse events. RESULTS: The result will generate a comprehensive suggestion for the treatment of PCV. CONCLUSION: The results of the network meta-analysis will be submitted in a peer-reviewed journal for publication. ETHICS AND DISSEMINATION: The study does not involve human subjects and requires no ethical approval or patient consent. The results of the network meta-analysis will be submitted in a peer-reviewed journal for publication and generate a comprehensive suggestion for the treatment of PCV.


Asunto(s)
Neovascularización Coroidal/tratamiento farmacológico , Metaanálisis en Red , Fotoquimioterapia/métodos , Revisiones Sistemáticas como Asunto , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Humanos , Ensayos Clínicos Controlados no Aleatorios como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
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