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1.
J Nat Med ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38926328

RESUMEN

Alzheimer's disease (AD) remains a challenging neurodegenerative disorder with limited therapeutic success. Traditional Chinese Medicine (TCM), as a promising new source for AD, still requires further exploration to understand its complex components and mechanisms. Here, focused on addressing Aß (1-40) aggregation, a hallmark of AD pathology, we employed a Thioflavin T fluorescence labeling method for screening the active molecular library of TCM which we established. Among the eight identified, 1,3-di-caffeoylquinic acid emerged as the most promising, exhibiting a robust binding affinity with a KD value of 26.7 nM. This study delves into the molecular intricacies by utilizing advanced techniques, including two-dimensional (2D) 15N-1H heteronuclear single quantum coherence nuclear magnetic resonance (NMR) and molecular docking simulations. These analyses revealed that 1,3-di-caffeoylquinic acid disrupts Aß (1-40) self-aggregation by interacting with specific phenolic hydroxyl and amino acid residues, particularly at Met-35 in Aß (1-40). Furthermore, at the cellular level, the identified compounds, especially 1,3-di-caffeoylquinic acid, demonstrated low toxicity and exhibited therapeutic potential by regulating mitochondrial membrane potential, reducing cell apoptosis, and mitigating Aß (1-40)-induced cellular damage. This study presents a targeted exploration of catechol compounds with implications for effective interventions in AD and sheds light on the intricate molecular mechanisms underlying Aß (1-40) aggregation disruption.

2.
Arch Gynecol Obstet ; 309(1): 295-304, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37787836

RESUMEN

PURPOSE: To investigate developmental competence and neonatal outcomes of nonpronuclear (0PN) zygotes following single vitrified-warmed blastocyst transfers (VBT). METHODS: The clinical, laboratorial and neonatal data of 996 patients with ≤ 38 years who underwent blastocyst culture and single VBT were retrospectively analyzed. The pregnancy and neonatal outcomes of VBT were compared between 0PN and 2PN blastocysts using propensity score matching (PSM). Moreover, Day 3 (D3) embryo development and blastocyst formation were compared between 0PN and 2PN zygotes. RESULTS: There were no significant differences in clinical pregnancy rate (CPR), live birth rate (LBR) and neonatal outcomes of VBT between the 0PN and 2PN blastocysts irrespectively of whether PSM was used. However, early abortion rate (EAR) was higher in blastocysts from 0PN D3 embryos > 10 cells (p < 0.05) before PSM. Moreover, the early developmental competence of 0PN zygotes was different from that of 2PN zygotes presenting higher percentages of D3 embryos ≤ 6 cells (p < 0.01) and > 10 cells (p < 0.01), lower available blastocyst formation rate (ABFR) (p < 0.01) and good-quality blastocyst formation rate (GBFR) (p < 0.01) in D3 embryos with 4-6 cells. ABFR and GBFR increased with cell number when compared among embryos with 4-6 cells, 7-10 cells and > 10 cells, irrespectively of 0PN or 2PN embryos. CONCLUSION: The early developmental competence of 0PN zygotes was different from that of 2PN zygotes, but did not influence pregnancy and neonatal outcomes following VBT. ABFR and GBFR increased with cell number, irrespectively of 0PN or 2PN embryos.


Asunto(s)
Transferencia de Embrión , Cigoto , Embarazo , Femenino , Recién Nacido , Humanos , Estudios Retrospectivos , Puntaje de Propensión , Índice de Embarazo , Blastocisto
3.
Taiwan J Obstet Gynecol ; 62(6): 817-822, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38008499

RESUMEN

OBJECTIVE: To investigate the relationship between serum progesterone (P) levels on the day of blastocyst transfer and pregnancy outcomes in frozen-thawed embryo transfer (FET) cycles using hormone replacement therapy (HRT) with oral dydrogesterone for strengthened luteal phase support (LPS). MATERIALS AND METHODS: This was a retrospective study including 1176 FET cycles. All patients received 40 mg of intramuscular (IM) P daily for endometrium transformation plus oral dydrogesterone 10 mg BID from transfer day for strengthened LPS. Pregnancy outcomes were compared between serum P levels on the transfer day ≥10 ng/ml and <10 ng/ml. Furthermore, cycles were divided into 10 groups by deciles of P and ongoing pregnancy rate (OPR) was calculated in each group. Analyses using deciles of serum P were completed to see if these could create further prognostic power. RESULTS: No differences were observed in clinical pregnancy rates (CPRs), OPRs and live birth rates (LBRs) between serum P levels ≥10 ng/ml and <10 ng/ml. Patients with serum P levels <5.65 ng/ml (10th percentile) had a significantly lower OPR (48.31% vs. 58.98%, p = 0.03) and LBR (43.22% vs. 57.75%, p = 0.003) than the rest of the patients. Multivariate logistic regression analysis showed serum P levels on the transfer day were not associated with pregnancy outcomes. CONCLUSION: Measuring serum P levels on the day of HRT-FET is of clinical importance. Lower serum P levels impact the success of HRT-FET cycles, suggesting that there may be a threshold below which it is difficult to improve pregnancy outcomes via oral dydrogesterone to strengthen LPS.


Asunto(s)
Didrogesterona , Resultado del Embarazo , Embarazo , Femenino , Humanos , Progesterona , Estudios Retrospectivos , Fase Luteínica , Lipopolisacáridos , Índice de Embarazo , Terapia de Reemplazo de Hormonas
4.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37685916

RESUMEN

Alzheimer's disease (AD) urgently needs innovative treatments due to the increasing aging population and lack of effective drugs and therapies. The amyloid fibrosis of AD-associated ß-amyloid (Aß) that could induce a series of cascades, such as oxidative stress and inflammation, is a critical factor in the progression of AD. Recently, peptide-based therapies for AD are expected to be great potential strategies for the high specificity to the targets, low toxicity, fast blood clearance, rapid cell and tissue permeability, and superior biochemical characteristics. Specifically, various chiral amino acids or peptide-modified interfaces draw much attention as effective manners to inhibit Aß fibrillation. On the other hand, peptide-based inhibitors could be obtained through affinity screening such as phage display or by rational design based on the core sequence of Aß fibrosis or by computer aided drug design based on the structure of Aß. These peptide-based therapies can inhibit Aß fibrillation and reduce cytotoxicity induced by Aß aggregation and some have been shown to relieve cognition in AD model mice and reduce Aß plaques in mice brains. This review summarizes the design method and characteristics of peptide inhibitors and their effect on the amyloid fibrosis of Aß. We further describe some analysis methods for evaluating the inhibitory effect and point out the challenges in these areas, and possible directions for the design of AD drugs based on peptides, which lay the foundation for the development of new effective drugs in the future.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides , Envejecimiento , Aminoácidos , Proteínas Amiloidogénicas
5.
J Agric Food Chem ; 71(31): 12004-12014, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37523494

RESUMEN

Umami peptides are small molecular weight oligopeptides that play a role in umami taste attributes. However, the identification of umami peptides is easily limited by environmental conditions, and the abundant source and high chromatographic separation efficiency remain difficult. Herein, we report a robust strategy based on a phage random linear heptapeptide library that targets the T1R1-Venus flytrap domain (T1R1-VFT). Two candidate peptides (MTLERPW and MNLHLSF) were readily identified with high affinity for T1R1-VFT binding (KD of MW-7 and MF-7 were 790 and 630 nM, respectively). The two peptides exhibited umami taste and significantly enhanced the umami intensity when added to the monosodium glutamate solution. Overall, this strategy shows that umami peptides could be developed via phage display technology for the first time. The phage display platform has a promising application to discover other taste peptides with affinity for taste receptors of interest and has more room for improvement in the future.


Asunto(s)
Péptidos , Receptores Acoplados a Proteínas G , Receptores Acoplados a Proteínas G/metabolismo , Péptidos/química , Glutamato de Sodio , Gusto
6.
ACS Appl Mater Interfaces ; 15(27): 32251-32261, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37377344

RESUMEN

Blood infection can release toxic bacterial lipopolysaccharides (LPSs) into bloodstream, trigger a series of inflammatory reactions, and eventually lead to multiple organ dysfunction, irreversible shock, and even death, which seriously threatens human life and health. Herein, a functional block copolymer with excellent hemocompatibility is proposed to enable broad-spectrum clearance of LPSs from whole blood blindly before pathogen identification, facilitating timely rescue from sepsis. A dipeptide ligand of histidine-histidine (HH) was designed as the LPS binding unit, and poly[(trimethylamine N-oxide)-co-(histidine-histidine)], a functional block copolymer combining the LPS ligand of HH and a zwitterionic antifouling unit of trimethylamine N-oxide (TMAO), was then designed by reversible addition-fragmentation chain transfer (RAFT) polymerization. The functional polymer achieved effective clearance of LPSs from solutions and whole blood in a broad-spectrum manner and had good antifouling and anti-interference properties and hemocompatibility. The proposed functional dihistidine polymer provides a novel strategy for achieving broad-spectrum clearance of LPSs, with potential applications in clinical blood purification.


Asunto(s)
Lipopolisacáridos , Polímeros , Humanos , Polímeros/química , Histidina , Ligandos
7.
Anal Chem ; 95(27): 10390-10397, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37358224

RESUMEN

Oxidation and protein phosphorylation are critical mechanisms involved in regulating various cellular activities. Increasing research has suggested that oxidative stress could affect the activities of specific kinases or phosphatases, leading to alterations in the phosphorylation status of certain proteins. Ultimately, these alterations can affect cellular signaling pathways and gene expression patterns. However, the relationship between oxidation and protein phosphorylation remains complex and not yet fully understood. Therefore, the development of effective sensors capable of detecting both oxidation and protein phosphorylation simultaneously presents an ongoing challenge. To address this need, we introduce a proof-of-concept nanochannel device that is dual-responsive to both H2O2 and phosphorylated peptide (PP). Specifically, we design a peptide GGGCEG(GPGGA)4CEGRRRR, which contains an H2O2-sensitive unit CEG, an elastic peptide fragment (GPGGA)4, and a phosphorylation site recognition fragment RRRR. When the peptides are immobilized on the inner walls of conical nanochannels in a polyethylene terephthalate membrane, this peptide-modified nanochannel device exhibits a sensitive response to both H2O2 and PPs. The peptide chains undergo a random coil-to-α-helix transition in response to H2O2, which leads to a close-to-open transition of the nanochannel, accompanied with a remarkable increase in the transmembrane ionic current. In contrast, binding of the peptides with PPs shields the positive charge of the RRRR fragments, causing a decrease of the transmembrane ionic current. These unique features enable the sensitive detection of reactive oxygen species released by 3T3-L1 cells stimulated by platelet-derived growth factor (PDGF) as well as PDGF-induced change in the PP level. Real-time kinase activity monitoring further confirms the device's potential utility for kinase inhibitor screening.


Asunto(s)
Peróxido de Hidrógeno , Péptidos , Peróxido de Hidrógeno/farmacología , Péptidos/metabolismo , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Fosforilación , Estrés Oxidativo
8.
Adv Mater ; 35(33): e2302560, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37247257

RESUMEN

Lipopolysaccharide (LPS) is the primary bacterial toxin that is vital to the pathogenesis and progression of sepsis associated with extremely high morbidity and mortality worldwide. However, specific clearance of LPS from circulating blood is highly challenging because of the structural complexity and its variation between/within bacterial species. Herein, a robust strategy based on phage display screening and hemocompatible peptide bottlebrush polymer design for specific clearance of targeted LPS from circulating blood is proposed. Using LPS extracted from Escherichia coli as an example, a novel peptide (HWKAVNWLKPWT) with high affinity (KD < 1.0 nм), specificity, and neutralization activity (95.9 ± 0.1%) against the targeted LPS is discovered via iterative affinity selection coupled with endotoxin detoxification screening. A hemocompatible bottlebrush polymer bearing the short peptide [poly(PEGMEA-co-PEP-1)] exhibits high LPS selectivity to reduce circulating LPS level from 2.63 ± 0.01 to 0.78 ± 0.05 EU mL-1 in sepsis rabbits via extracorporeal hemoperfusion (LPS clearance ratio > 70%), reversing the LPS-induced leukocytopenia and multiple organ damages significantly. This work provides a universal paradigm for developing a highly selective hemoadsorbent library fully covering the LPS family, which is promising to create a new era of precision medicine in sepsis therapy.


Asunto(s)
Lipopolisacáridos , Sepsis , Animales , Conejos , Endotoxinas , Sepsis/terapia , Péptidos , Bacterias
9.
Sci Adv ; 9(21): eade0293, 2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37235655

RESUMEN

Innovative therapeutic strategies are urgently needed for Alzheimer's disease (AD) due to the increasing size of the aging population and the lack of effective drug treatment. Here, we report the therapeutic effects of extracellular vesicles (EVs) secreted by microglia, including macrosomes and small EVs, on AD-associated pathology. Macrosomes strongly inhibited ß-amyloid (Aß) aggregation and rescued cells from Aß misfolding-induced cytotoxicity. Furthermore, macrosome administration reduced Aß plaques and ameliorated cognitive impairment in mice with AD. In contrast, small EVs slightly promoted Aß aggregation and did not improve AD pathology. Proteomic analysis of small EVs and macrosomes revealed that macrosomes harbor several important neuroprotective proteins that inhibit Aß misfolding. In particular, the small integral membrane protein 10-like protein 2B in macrosomes has been shown to inhibit Aß aggregation. Our observations provide an alternative therapeutic strategy for the treatment of AD over conventional ineffective drug treatments.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Ratones , Animales , Enfermedad de Alzheimer/metabolismo , Proteómica , Péptidos beta-Amiloides/metabolismo , Microglía/metabolismo , Modelos Animales de Enfermedad
10.
Small ; 19(29): e2207932, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37052499

RESUMEN

Self-assembly of cellulose nanocrystals (CNCs) is invaluable for the development of sustainable optics and photonics. However, the functional failure of CNC-derived materials in humid or liquid environments inevitably impairs their development in biomedicine, membrane separation, environmental monitoring, and wearable devices. Here, a facile and robust method to fabricate insoluble hydrogels in a self-assembled CNC-polyvinyl alcohol (PVA) system is reported. Due to the reconstruction of inter- or intra-molecular hydrogen bond interactions, thermal dehydration makes an optimized CNC/PVA photonic film form a stable hydrogel network in an aqueous solution rather than dissolve. Notably, the resulting hydrogel exhibits superb mechanical performance (stress up to 3.3 Mpa and tough up to 0.73 MJ m-3 ) and reversible conversion between dry and wet states, enabling it convenient for specific functionalization. Sodium alginate (SA) can be adsorbed into the CNC photonic structure by swelling dry CNC/PVA film in a SA solution. The prepared hydrogel showcases the comprehensive properties of freezing resistance (-20°C), strong adhesion, satisfactory biocompatibility, and highly sensitive and selective Ca2+ sensing. The material could act as a portable wearable patch on the skin for the continuous analysis of calcium trends during different physical exercises, facilitating their development in precision nutrition and health monitoring.


Asunto(s)
Celulosa , Nanopartículas , Celulosa/química , Calcio , Sudor , Óptica y Fotónica , Nanopartículas/química , Alcohol Polivinílico/química , Hidrogeles/química
11.
Chem Commun (Camb) ; 59(29): 4368-4371, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36946304

RESUMEN

We have developed a reactive oxygen species (ROS) sensor based on nanopores modified with GGGCEG(GPGGA)4CEG. The formation of an intramolecular disulfide bond oxidized by ROS leads to conformation changes in GGGCEG(GPGGA)4CEG, which then induces an obvious change in the size of the nanopores and a corresponding ionic current change. This work allows the accurate and dynamic monitoring of ROS through the combination of (GPGGA)4 and nanopores.

12.
RSC Adv ; 12(46): 29845-29851, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36321087

RESUMEN

TBHQ is a significant synthetic antioxidant, but excessive use of TBHQ is harmful to human health. Therefore, the preparation of a high-efficiency TBHQ electrochemical sensor is of great significance. In this work, a core-shell structured Co3O4@PPy composite is synthesized for TBHQ determination and exhibits remarkable electrochemical properties. The core-shell structure of Co3O4@PPy composite shows the synergistic effects of fast charge transfer, rich active surface area and more active sites. Under optimal conditions, the linear range of the developed sensor is 0.2-600 µM, and the detection limit is 0.05 µM (S/N = 3). In addition, it also has good stability and reproducibility due to the stable protective role of the PPy shell. The proposed sensor can also be applied to practical sample detection.

13.
ACS Chem Neurosci ; 13(14): 2154-2163, 2022 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35818957

RESUMEN

Misfolding and accumulation of amyloid-ß (Aß) to form senile plaques are the main neuropathological signatures of Alzheimer's disease (AD). Decreasing Aß production, inhibiting Aß aggregation, and clearing Aß plaques are thus considered an important strategy for AD treatment. However, numerous drugs cannot enter the AD clinical trials due to unsatisfactory biocompatibility, poor blood-brain barrier penetration, little biomarker impact, and/or low therapeutic indicators. Here, a pair of chiral aspartic acid-modified 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (l- and d-Asp-DPPE) are prepared to build stabilized chiral liposomes. We find that both l- and d-liposomes are able to rescue Aß aggregation-induced apoptosis, oxidative stress, and calcium homeostasis, in which the effect of d-liposomes is more obvious than that of l-ones. Furthermore, in AD model mice (APPswe/PS1d9 double-transgenic mice), chiral liposomes not only show biosafety but also strongly improve cognitive deficits and reduce Aß deposition in the brain. Our results suggest that chiral liposomes, particularly, d-liposomes, could be a potential therapeutic approach for AD treatment. This study opens new horizons by showing that liposomes will be used for drug development in addition to delivery and targeting functions.


Asunto(s)
Enfermedad de Alzheimer , Precursor de Proteína beta-Amiloide , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Ácido Aspártico , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Liposomas , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/patología , Ratones , Ratones Transgénicos , Fosfolípidos , Placa Amiloide/patología , Presenilina-1/genética , Presenilina-1/metabolismo
14.
Biomaterials ; 282: 121418, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35202931

RESUMEN

Umami is one of the basic taste sensing, and represents the recognition of N-containing compounds capable of evaluating the nutritious contents of food. Although several sensors have been developed, the assessment of umami intensity remains challenging due to the limitations of sensor specificity, sensitivity, and performance stability. Here we present a biomimetic conical nanochannels system integrated with Venus flytrap (VFT) domain from human umami receptor T1R1 subunit to meet the concern. By taking advantage of sensitive transmembrane ionic flux change, the functional nanochannels could precisely distinguish umami substances from other tastants. Detailed mechanism analysis reveals that specific binding between T1R1 and umami substances triggers local conformation change and surface charge redistribution of the protein, which modulates the ionic current. This study initiates the application of nanochannel device in taste perception, which could help to disclose umami perception mechanism and screen new umami substances.


Asunto(s)
Biomimética , Receptores Acoplados a Proteínas G , Humanos , Iones , Receptores Acoplados a Proteínas G/metabolismo , Gusto
15.
Br J Radiol ; 95(1129): 20200381, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34672681

RESUMEN

OBJECTIVES: To evaluate the effect of the position of microcoil proximal end on the incidence of microcoil dislocation during CT-guided microcoil localization of pulmonary nodules (PNs). METHODS: This retrospective study included all patients with PNs who received CT-guided microcoil localization before video-assisted thoracoscopic urgery (VATS) resection from June 2016 to December 2019 in our institution. The microcoil distal end was less than 1 cm away from the nodule, and the microcoil proximal end was in the pleural cavity (the pleural cavity group) or chest wall (the chest wall group). The length of microcoil outside the pleura was measured and divided into less than 0.5 cm (group A), 0.5 to 2 cm (group B) and more than 2 cm (group C). Microcoil dislocation was defined as complete retraction into the lung (type I) or complete withdrawal from the lung (type II). The rate of microcoil dislocation between different groups was compared. RESULTS: A total of 519 consecutive patients with 571 PNs were included in this study. According to the position of microcoils proximal end on post-marking CT, there were 95 microcoils in the pleural cavity group and 476 in the chest wall group. The number of microcoils in group A, B, and C were 67, 448 and 56, respectively. VATS showed dislocation of 42 microcoils, of which 30 were type II and 12 were type I. There was no statistical difference in the rate of microcoil dislocation between the pleural cavity group and the chest wall group (6.3% vs 7.6%, x2 = 0.18, p = 0.433). The difference in the rate of microcoil dislocation among group A, B, and C was statistically significant (11.9%, 5.8%, and 14.3% for group A, B, and C, respectively, x2 = 7.60, p = 0.008). In group A, 75% (6/8) of dislocations were type I, while all eight dislocations were type II in group C. CONCLUSIONS: During CT-guided microcoil localization of PNs, placing the microcoil proximal end in the pleura cavity or chest wall had no significant effect on the incidence of microcoil dislocation. The length of microcoil outside the pleura should be 0.5 to 2 cm to reduce the rate of microcoil dislocation. ADVANCES IN KNOWLEDGE:: CT-guided microcoil localization can effectively guide VATS to resect invisible and impalpable PNs. Microcoil dislocation is the main cause of localization failure. The length of microcoil outside the pleura is significantly correlated with the rate and type of microcoil dislocation. Placing the microcoil proximal end in the pleura cavity or chest wall has no significant effect on the rate of microcoil dislocation.


Asunto(s)
Marcadores Fiduciales , Neoplasias Pulmonares/diagnóstico por imagen , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Radiografía Intervencional/métodos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Femenino , Marcadores Fiduciales/efectos adversos , Marcadores Fiduciales/estadística & datos numéricos , Migración de Cuerpo Extraño/diagnóstico por imagen , Humanos , Pulmón/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Masculino , Nódulos Pulmonares Múltiples/cirugía , Cavidad Pleural/diagnóstico por imagen , Estudios Retrospectivos , Nódulo Pulmonar Solitario/cirugía , Cirugía Torácica Asistida por Video , Pared Torácica/diagnóstico por imagen
16.
Analyst ; 146(22): 6846-6851, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34617079

RESUMEN

The preparation of ideal sensing materials is of great significance for the realization of high-performance electrochemical analysis. However, in previous methods, most electrode materials are firstly synthesized and dispersed, finally dropped on the electrode surface, which led to complicated operation and poor adhesion between the materials and electrode surface. In this study, a PEDOT-CNT hybrid film has been prepared by combining carboxylated carbon nanotubes as dopants with PEDOT through scalable and easy-to-operate electrochemical deposition. The PEDOT-CNT modified electrode shows excellent performance for the determination of tertiary butylhydroquinone, with a wide linear range of 0.5-820 µM, a low detection limit of 0.12 µM, high stability and reproducibility. In addition, the mechanism of electrodeposition of CNTs and tertiary butylhydroquinone has also been discussed briefly. The PEDOT-CNT hybrid film possesses the preeminent sensing capacity in monitoring tertiary butylhydroquinone, providing research clues for the design and development of new electrode materials in the future.

17.
J Mater Chem B ; 9(23): 4690-4699, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34076032

RESUMEN

Sialic acids located at the terminal end of glycans are densely attached to cell surfaces and play crucial and distinctive roles in a variety of physiological and pathological processes, such as neural development, cell-cell interactions, autoimmunity and cancers. However, due to the subtle structural differences of sialic acid species and the complicated composition of glycans, the precise recognition of sialylated glycans is difficult. Here, a fluorescent dynamic response system based on a pyrene-conjugated histidine (PyHis) supramolecular gel is proposed. Driven by π-π stacking and intermolecular hydrogen bonds, PyHis exhibits a strong self-assembly ability and forms stable gels. It is found that introduction of N-acetylneuraminic acid (a typical sialic acid) can prevent this self-assembly process, whereas other monosaccharides or sialic acid analogs have no significant effect on it. Interestingly, a sialylated glycan also has a remarkable inhibitory effect on the gel formation, which highlights the high selectivity of the gel dynamic response system. Analysis of the mechanism reveals that the sialic acid or sialylated glycan can interact closely with two PyHis molecules stacked together in the assemblies via hydrogen bonding interactions, thereby preventing the ordered accumulation of the gelators. It is worth noting that the high-efficiency sialic acid recognition effect is not observed at the single molecule level but at the supramolecular level, indicating the unique superiority of the supramolecular self-assembly system in biomolecular recognition and response. This work shows the promising prospects of using supramolecular gels in assembly engineering, regenerative medicine, tumour cell sorting and cancer diagnosis.


Asunto(s)
Geles/química , Microscopía de Fuerza Atómica/métodos , Ácido N-Acetilneuramínico/metabolismo , Enlace de Hidrógeno , Espectroscopía Infrarroja por Transformada de Fourier/métodos
18.
ACS Appl Mater Interfaces ; 13(14): 17118-17128, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33793208

RESUMEN

Cellulose nanocrystals (CNCs) are powerful photonic building blocks for the fabrication of biosourced colored films. A combination of the advantages of self-assembled CNCs and multiple templating agents offers access to the development of novel physicochemical sensors, structural coatings, and optic devices. However, due to the inherent brittleness and water instability of CNC-derived materials, their further applications are widely questionable and restrictive. Here, a soft polymer of poly(vinyl alcohol) (PVA) was introduced into the rigid CNC system to balance molecular interactions, whereafter two hard/soft nanocomposites were fastened through a cross-linking reaction of glutaraldehyde (GA), resulting in a highly flexible, water-stable, and chiral nematic CNC composite film through an evaporation-induced self-assembly technique. For a 1.5 wt % GA-cross-linked 70 wt % CNC loading film, its treatment with harsh hydrophilic exposure (soaking in a strong acid, strong base, and seawater) and various organic solvents show exceptional solvent-resistant abilities. Furthermore, the film can even withstand a weight of 167 g cm-2 without failure, which is a highly stiff and durable character. Importantly, the film remains a highly ordered chiral nematic organization, being able to act as a highly transparent substrate for selective reflection of left-handed circularly polarized light, preparing fully covered and patterned full-color coatings on various substrates. Our work paves the way for applications in low-cost, durable, and photonic cellulosic coatings.

19.
Br J Radiol ; 94(1118): 20190930, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33245675

RESUMEN

OBJECTIVES: To compare CT-guided transthoracic cutting needle biopsy (TCNB) with transthoracic aspiration needle biopsy (TANB) for pulmonary lesions with respect to the diagnostic accuracy and complication rate. METHODS: Of the 859 cases that underwent consecutive CT-guided biopsy of pulmonary lesions, 713 cases confirmed by surgical pathology or clinical follow-up were enrolled. Of these, the first consecutive 275 cases underwent TANB, and the remaining 438 received TCNB. The final diagnosis determined the accuracy of biopsy. Based on the post-biopsy CT and clinical medical records, the presence or absence of biopsy-related complications was determined. The χ2 test was used to compare the differences between TCNB and TANB in terms of diagnostic accuracy and complication rate. RESULTS: Among the 713 biopsy lesions, the final diagnosis was malignant in 411 cases and benign in 302 cases. As compared to TANB, the diagnostic accuracy of TCNB (98.9% vs 93.8%, χ2 = 14.35, p < 0.01), sensitivity to malignant lesions (97.8% vs 90.6%, χ2 = 10.58, p < 0.01), negative predictive value (97.6% vs 84.8%, χ2 = 19.03, p < 0.01), and specific diagnostic rate for benign lesions (73.4% vs 57.9%, χ2 = 7.29, p < 0.01) were improved. On the other hand, a statistical difference was detected between TCNB and TANB with respect to the incidence of pneumothorax (20.6% vs 13.1%, χ2 = 6.46, p = 0.01), hemorrhage (32.2% vs 13.1%, χ2 = 33.03, p < 0.01), and hemoptysis (8.2% vs 3.3%, χ2 = 6.87, p < 0.01). One patient died just several minutes after TCNB due to severe hemorrhage with hemoptysis. CONCLUSIONS: Compared to TANB, CT-guided TCNB improves the diagnostic accuracy of pulmonary lesions, but complication rate increases significantly. ADVANCES IN KNOWLEDGE: In general, TCNB should be recommended, especially for highly suspicious benign lesions. For patients with small lesions adjacent to vessels or vessels within the lesion, TANB should be considered.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Radiografía Intervencional/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Biopsia con Aguja , Diseño de Equipo , Femenino , Humanos , Biopsia Guiada por Imagen/instrumentación , Biopsia Guiada por Imagen/métodos , Pulmón/diagnóstico por imagen , Pulmón/patología , Masculino , Persona de Mediana Edad , Agujas , Sensibilidad y Especificidad
20.
Analyst ; 146(2): 691-697, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33210665

RESUMEN

A portable electrode with usability, availability, and high-sensitivity is of great significance for effective on-site detection in practical situations. In this paper, a novel flexible, disposable sensor for Cd2+ and Pb2+ with ultrahigh sensitivity and a fast response, based on acid-etched Fe/Fe2O3 encapsulated into a disposable carbon cloth electrode, has been successfully fabricated. Differential pulse anode stripping voltammetry (DPASV) was used to investigate the stripping behavior of Cd2+ and Pb2+, achieving high sensitivity for Cd2+ and Pb2+ (338.7 and 408.0 µA mM-1 cm-2) with limits of detection (LODs) of 0.42 ppb and 0.50 ppb, respectively. Meanwhile, remarkable stability and reproducibility were obtained. Such an electrode can detect Cd2+ and Pb2+ in actual water samples so this is a good candidate to act as a simple and convenient sensor for general applications. More importantly, the novel disposable electrode exhibited the unique advantages of convenience, portability, and reliability compared to a conventional electrode, which may make it an alternative advantageous choice for practical on-site detection.

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