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1.
Small ; 19(2): e2204719, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36333119

RESUMO

As the leading cause of death, heart attacks result in millions of deaths annually, with no end in sight. Early intervention is the only strategy for rescuing lives threatened by heart disease. However, the detection time of the fastest heart-attack detection system is >15 min, which is too long considering the rapid passage of life. In this study, a machine learning (ML)-driven system with a simple process, low-cost, short detection time (only 10 s), and high precision is developed. By utilizing a functionalized nanofinger structure, even a trace amount of biomarker leaked before a heart attack can be captured. Additionally, enhanced Raman profiles are constructed for predictive analytics. Five ML models are developed to harness the useful characteristics of each Raman spectrum and provide early warnings of heart attacks with >98% accuracy. Through the strategic combination of nanofingers and ML algorithms, the proposed warning system accurately provides alerts on silent heart-attack attempts seconds ahead of actual attacks.


Assuntos
Infarto do Miocárdio , Análise Espectral Raman , Humanos , Análise Espectral Raman/métodos , Infarto do Miocárdio/diagnóstico , Aprendizado de Máquina , Algoritmos
2.
Pharm Res ; 40(2): 375-386, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35478298

RESUMO

Acalabrutinib, a selective Bruton's tyrosine kinase inhibitor, is a biopharmaceutics classification system class II drug. The aim of this study was to develop a physiologically based pharmacokinetic (PBPK) model to mechanistically describe absorption of immediate release capsule formulation of acalabrutinib in humans. Integration of in vitro biorelevant measurements, dissolution studies and in silico modelling provided clinically relevant inputs for the mechanistic absorption PBPK model. The batch specific dissolution data were integrated in two ways, by fitting a diffusion layer model scalar to the drug product dissolution with integration of drug substance laser diffraction particle size data, or by fitting a product particle size distribution to the dissolution data. The latter method proved more robust and biopredictive. In both cases, the drug surface solubility was well predicted by the Simcyp simulator. The model using the product particle size distribution (P-PSD) for each clinical batch adequately captured the PK profiles of acalabrutinib and its active metabolite. Average fold errors were 0.89 for both Cmax and AUC, suggesting good agreement between predicted and observed PK values. The model also accurately predicted pH-dependent drug-drug interactions between omeprazole and acalabrutinib, which was similar across all clinical formulations. The model predicted acalabrutinib geometric mean AUC ratios (with omeprazole vs acalabrutinib alone) were 0.51 and 0.68 for 2 batches of formulations, which are close to observed values of 0.43 and 0.51~0.63, respectively. The mechanistic absorption PBPK model could be potentially used for future applications such as optimizing formulations or predicting the PK for different batches of the drug product.


Assuntos
Modelos Biológicos , Omeprazol , Humanos , Liberação Controlada de Fármacos , Solubilidade , Simulação por Computador , Concentração de Íons de Hidrogênio , Absorção Intestinal/fisiologia , Administração Oral
3.
Br J Clin Pharmacol ; 88(8): 3716-3729, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35165925

RESUMO

AIMS: Clinical drug interaction studies with itraconazole and rifampicin have demonstrated that acalabrutinib is a sensitive substrate of CYP3A. A physiologically based pharmacokinetic (PBPK) model was developed based on the data of these studies. One of the active CYP3A metabolites, ACP-5862, was identified but never studied in a drug interaction scenario. This study aims to evaluate both parent and metabolite exposure change with coadministration of moderate CYP3A inhibitors and its impact on safety and efficacy. METHODS: In an open label, randomized, 2-period study, we investigated the effect of coadministration of fluconazole or isavuconazole on the pharmacokinetics of acalabrutinib. Bruton tyrosine kinase receptor occupancy and safety were compared between different treatments. Experimental data were compared to PBPK simulation results. RESULTS: Least square means of acalabrutinib maximum plasma concentration and area under the curve increased 1.37 (1.14-1.64) and 1.60 (1.45-1.77)-fold in the presence of isavuconazole and 1.48 (1.10-1.98) and 2.16 (1.94-2.40)-fold in the presence of fluconazole, respectively. For ACP-5862, these values are 0.72 (0.63-0.82) and 0.91 (0.86-0.97) fold for isavuconazole and 0.65 (0.49-0.87) and 0.95 (0.91-0.99) fold for fluconazole coadministration. The PBPK model was able to recover acalabrutinib and ACP-5862 PK profiles in the study. Bruton tyrosine kinase receptor occupancy change was minimal in the presence of isavuconazole. There were no deaths, serious adverse events (AEs), or subject discontinuation due to AEs in this study. Only mild (Grade 1) AEs were reported during the study, by 17% of the study population. CONCLUSION: Our results demonstrate the impact of fluconazole and isavuconazole on the pharmacokinetics of acalabrutinib and ACP-5862, and suggest that no dose adjustment is needed for concomitant administration with moderate CYP3A inhibitors. the current PBPK model can be used to propose dose adjustment for drug interactions via CYP3A.


Assuntos
Inibidores do Citocromo P-450 CYP3A , Citocromo P-450 CYP3A , Área Sob a Curva , Benzamidas , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacologia , Interações Medicamentosas , Fluconazol/efeitos adversos , Humanos , Modelos Biológicos , Pirazinas , Receptores Proteína Tirosina Quinases/metabolismo
4.
Nano Lett ; 21(8): 3465-3472, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33835802

RESUMO

Artificial neuronal devices that functionally resemble biological neurons are important toward realizing advanced brain emulation and for building bioinspired electronic systems. In this Communication, the stochastic behaviors of a neuronal oscillator based on the charge-density-wave (CDW) phase transition of a 1T-TaS2 thin film are reported, and the capability of this neuronal oscillator to generate spike trains with statistical features closely matching those of biological neurons is demonstrated. The stochastic behaviors of the neuronal device result from the melt-quench-induced reconfiguration of CDW domains during each oscillation cycle. Owing to the stochasticity, numerous key features of the Hodgkin-Huxley description of neurons can be realized in this compact two-terminal neuronal oscillator. A statistical analysis of the spike train generated by the artificial neuron indicates that it resembles the neurons in the superior olivary complex of a mammalian nervous system, in terms of its interspike interval distribution, the time-correlation of spiking behavior, and its response to acoustic stimuli.


Assuntos
Modelos Neurológicos , Tantálio , Potenciais de Ação , Animais , Dissulfetos , Neurônios , Processos Estocásticos
5.
Technol Cult ; 63(1): 87-117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35000960

RESUMO

This article explores the little-known history of bingata, a textile technology of resist dyeing developed in the Ryukyu Islands (modern-day Okinawa, Japan) during the sixteenth to eighteenth centuries and later, promoted as traditional folk craft under Japanese colonialism. Located at the center of tributary and trading networks linking Northeast and Southeast Asia and, after 1600, Europe, the Ryukyus were an integral part of the early modern world. Tracing the circulation of Prussian blue from Europe to Asia, this article shows how shared materials and techniques afforded by trade networks linked the craft work of Ryukyu craftsmen to the experimental science of European dyer-chemists. In doing so, this article challenges longstanding binaries that oppose West and non-West, science and craft knowledge, and traditional folk crafts and modern technology. It argues that the reciprocal relationship between materials and techniques underpinned the knowledge-making practices of both Ryukyu dyers and European dyer-chemists.


Assuntos
Corantes , Têxteis , Ásia , Japão , Tecnologia
6.
Drug Metab Dispos ; 49(7): 530-539, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33958385

RESUMO

Accurately predicting the pharmacokinetics of compounds that are transporter substrates has been notoriously challenging using traditional in vitro systems and physiologically based pharmacokinetic (PBPK) modeling. The objective of this study was to use PBPK modeling to understand the translational accuracy of data generated with human embryonic kidney 293 (HEK293) cells overexpressing the hepatic uptake transporters organic anion transporting polypeptide (OATP) 1B1/3 with and without plasma while accounting for transporter expression. Models of four OATP substrates, two with low protein binding (pravastatin and rosuvastatin) and two with high protein binding (repaglinide and pitavastatin) were explored, and the OATP in vitro data generated in plasma incubations were used for a plasma model, and in buffer incubations for a buffer model. The pharmacokinetic parameters and concentration-time profiles of pravastatin and rosuvastatin were similar and well predicted (within 2-fold of observed values) using the plasma and buffer models without needing an empirical scaling factor, whereas the dispositions of the highly protein bound repaglinide and pitavastatin were more accurately simulated with the plasma models than the buffer models. This work suggests that data from HEK293 overexpressing transporter cells corrected for transporter expression represent a valid approach to improve bottom-up PBPK modeling for highly protein bound OATP substrates with plasma incubations and low protein binding OATP substrates with or without plasma incubations. SIGNIFICANCE STATEMENT: This work demonstrates the bottom-up approach of using in vitro data directly without employing empirical scaling factors to predict the intravenous pharmacokinetic (PK) profiles reasonably well for four organic anion transporting polypeptide (OATP) substrates. Based on these results, using HEK293 overexpressing cells, examining the impact of plasma for highly bound compounds, and incorporating transporter quantitation for the lot in which the in vitro data were generated represents a valid approach to achieve more accurate prospective PK predictions for OATP substrates.


Assuntos
Descoberta de Drogas/métodos , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Modelos Biológicos , Plasma/metabolismo , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/metabolismo , Administração Intravenosa , Carbamatos/administração & dosagem , Carbamatos/farmacocinética , Células HEK293 , Humanos , Piperidinas/administração & dosagem , Piperidinas/farmacocinética , Pravastatina/administração & dosagem , Pravastatina/farmacocinética , Quinolinas/administração & dosagem , Quinolinas/farmacocinética , Rosuvastatina Cálcica/administração & dosagem , Rosuvastatina Cálcica/farmacocinética
7.
Angew Chem Int Ed Engl ; 59(34): 14647-14655, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32453890

RESUMO

The mode of asymmetric induction in an enantioselective intramolecular allylic substitution reaction catalyzed by a combination of palladium and a chiral phosphoric acid was investigated by a combined experimental and statistical modeling approach. Experiments to probe nonlinear effects, the reactivity of deuterium-labeled substrates, and control experiments revealed that nucleophilic attack to the π-allylpalladium intermediate is the enantio-determining step, in which the chiral phosphate anion is involved in stereoinduction. Using multivariable linear regression analysis, we determined that multiple noncovalent interactions with the chiral environment of the phosphate anion are integral to enantiocontrol in the transition state. The synthetic protocol to form chiral pyrrolidines was further applied to the asymmetric construction of C-O bonds at fully substituted carbon centers in the synthesis of chiral 2,2-disubstituted benzomorpholines.


Assuntos
Modelos Estatísticos , Paládio/química , Ácidos Fosfóricos/química , Catálise , Estereoisomerismo
8.
Drug Metab Dispos ; 47(9): 966-973, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31266752

RESUMO

GDC-0810 (Cheeti et al., 2018) is an orally bioavailable, selective estrogen receptor (ER) degrader developed to treat ER-positive breast cancer. A first-in-human (FIH) dose escalation phase I study (n = 41) was conducted to characterize the pharmacokinetics (PK) of GDC-0810 and its two major metabolites. GDC-0810 demonstrated linear PK from 100 to 600 mg given once daily. The mean terminal half-life following a single 600 mg dose was approximately 8 hours. Since GDC-0810 is a potent in vitro inhibitor of organic anion transporting polypeptide (OATP) 1B1/3, the kinetic profile of coproporphyrin I (CPI), a promising endogenous biomarker for OATP1B1/3, was analyzed retrospectively in a subset of the plasma samples collected in the same FIH study. CPI exhibited a GDC-0810 dose-dependent increase, suggesting in vivo inhibition of OATP1B transporters. To quantitatively predict the magnitude of OATP1B-mediated drug-drug interactions (DDIs) with pravastatin (a known OATP1B substrate), the in vivo unbound inhibition constant was first estimated using a one-compartment model, and then incorporated to a physiologically based pharmacokinetic model. The model showed some underestimation of the magnitude of the DDI when compared with a clinical DDI study result, while prediction had a relatively large uncertainty due to the small effect size, limited sample size, and variability in CPI kinetics. In conclusion, this study characterized the pharmacokinetic profiles of GDC-0810 in breast cancer patients and demonstrated the utility of CPI in detecting OATP1B-mediated DDIs of a new molecular entity as early as FIH study. SIGNIFICANCE STATEMENT: Endogenous biomarkers of transporters have recently been shown to be promising tools in evaluating the risk of clinical transporter-mediated DDIs. This is the first study to report a pharmacokinetic interaction between an investigational molecule and a transporter biomarker in a first-in-human study. The observed interaction and model-based analysis and the prediction provide important insights on the novel approach to quantitatively predict transporter-mediated DDIs as early as FIH studies in the clinical development.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cinamatos/farmacocinética , Indazóis/farmacocinética , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/metabolismo , Administração Oral , Adulto , Idoso , Antineoplásicos , Biomarcadores/análise , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Cinamatos/administração & dosagem , Coproporfirinas/análise , Coproporfirinas/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Estudos de Viabilidade , Feminino , Meia-Vida , Humanos , Indazóis/administração & dosagem , Pessoa de Meia-Idade , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/metabolismo
9.
Drug Metab Dispos ; 47(5): 547-555, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30858239

RESUMO

Duocarmycins [including cyclopropyl pyrroloindole (CPI) or cyclopropyl benzoindole (CBI)] are a class of DNA minor-groove alkylators and seco-CPI/CBIs are synthetic pro-forms that can spirocyclize to CPI/CBI. Bis-CPI/CBIs are potential drug candidates because of their enhanced cytotoxicity from DNA crosslinking, but it is difficult to analyze them for structure-activity correlation because of their DNA reactivity. To study their DNA alkylation, neutral thermal hydrolysis has been frequently applied to process depurination. However, unwanted side reactions under this condition have been reported, which could lead to poor correlation of DNA alkylation data with efficacy results, especially for bis-CPI/CBIs. In this study, an acidic depurination method was developed and applied for analysis of DNA alkylation and shown to be an easier and milder method than the traditional neutral thermal hydrolysis. DNA alkylation and stability of three bis-seco-CBIs were characterized in comparison with two mono-seco-CPIs. The results suggested that: 1) The acidic depurination method was capable of capturing a more representative population, sometimes a different population, of DNA adducts as they existed on DNA compared with the heat depurination method. 2) Di-adenine adducts were captured as expected for the CBI dimers, although the major type of adduct was still mono-adenine adducts. 3) The rate of DNA alkylation, DNA adduct profile, and relative amounts of di-adduct versus mono-adduct were significantly affected by the size, and possibly lipophilicity, of the nonalkylating part of the molecules. 4) Spirocyclization and amide hydrolysis represented two major pathways of degradation. Overall, by applying acidic depurination analyses, this study has illustrated DNA adduct characteristics of novel bis-seco-CBIs with dominating mono-alkylation and provides an alternative method for evaluating DNA minor-groove alkylators. These findings provide an effective analytical tool to evaluate DNA alkylators and to study the DNA alkylation that is a disposition mechanism of these compounds.


Assuntos
Alquilação/fisiologia , Antineoplásicos Alquilantes/metabolismo , DNA/metabolismo , Duocarmicinas/metabolismo , Adenina/metabolismo , Alquilantes/metabolismo , Adutos de DNA/metabolismo
10.
Technol Cult ; 60(2): 574-582, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31204345

RESUMO

Joseph Needham offered a vision of history that united his understanding of the physical world with his interpretation of social process, in which the material, social, and ideal realms were reciprocally constituted. This essay explores Needham's ideas about matter and form to show how he developed a systematic theory of materialism in his early writings on science and social change. Shifting the ground of discourse in Needham's project from "science" to "materialism," the essay brings him into conversation with new materialists to reflect on the ongoing challenges in theorizing the relationship between social and material phenomena. Calling into question an all-encompassing materiality that sacrifices the role of determinate structures and histories in the production of the world, the essay asks: How can we formulate a framework of material/-ity/-ism that does not dispense with or occlude the already embedded politics of culture, social relations of production, and historical contingency?

11.
Mol Pharm ; 15(11): 5103-5113, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30222362

RESUMO

Permeability assays are commonly conducted with Madin-Darby canine kidney (MDCK) cells to predict the intestinal absorption of small-molecule drug candidates. In addition, MDCK cells transfected to overexpress efflux transporters are often used to identify substrates. However, MDCK cells exhibit endogenous efflux activity for a significant proportion of experimental compounds, potentially leading to the underestimation of permeability and confounded findings in transport studies. The goal of this study was to evaluate canine Mdr1 knockout MDCK (gMDCKI) cells in permeability screening and human MDR1 substrate determination in a drug discovery setting. The gMDCKI cells were established by CRISPR-Cas9-mediated knockout of the canine Mdr1 gene in MDCKI wildtype (wt) cells. A comparison of efflux ratios (ER) between MDCKI wt and gMDCKI showed that out of 135 compounds tested, 38% showed efflux activity in MDCKI wt, while no significant efflux was observed in gMDCKI cells. Apparent permeability (Papp) from apical-to-basolateral (A-to-B) and basolateral-to-apical were near unity in gMDCKI cells, which approximated passive permeability, and 17% of compounds demonstrated increases in their Papp A-to-B values. Overexpression of human MDR1 in gMDCKI (gMDCKI-MDR1) cells enabled substrate determination without the contribution of endogenous efflux, and the assay was able to deconvolute ambiguous results from MDCKI-MDR1 and identify species differences in substrate specificity. An analysis of 395 and 474 compounds in gMDCKI and gMDCKI-MDR1, respectively, suggested physicochemical properties that were associated with low permeability correlated with MDR1 recognition. Poorly permeable compounds and MDR1 substrates were more likely to be large, flexible, and more capable of forming external hydrogen bonds. On the basis of our evaluation, we concluded that gMDCKI is a better cell line for permeability screening and efflux substrate determination than the MDCK wt cell line.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Cães , Avaliação Pré-Clínica de Medicamentos/métodos , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Células Madin Darby de Rim Canino , Permeabilidade
12.
Pharm Res ; 35(12): 244, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367284

RESUMO

The Publisher regrets the typesetting mistake of retaining incorrect text in the Figure 1 caption. The correct text for the caption is "Molecular Structure of GDC-0810 NMG Salt". The original article has been corrected.

13.
Pharm Res ; 35(12): 233, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30324422

RESUMO

PURPOSE: GDC-0810, administered orally, was used in Phase I and II clinical studies to treat estrogen receptor positive breast cancers. It contains N-methyl-D-glucamine (NMG) salt of GDC-0810 with 10% sodium lauryl sulfate (SLS) as a surfactant and 15% sodium bicarbonate (NaHCO3) as an alkalizing agent to aid dissolution. To improve the processability of the formulation and reduce potential mucosal irritation in future Phase III clinical studies, the salt form and the amount of excipient required further optimization. To achieve this, we employed a novel "Make and Test in Parallel" strategy that facilitated selecting formulation in a rapid timeframe. METHODS: RapidFACT®, a streamlined, data-driven drug product optimization platform was used to bridge Phase I/II and Phase III formulations of GDC-0810. Five prototype formulations, varying in either the form of active pharmaceutical ingredient and/or the levels of the excipients SLS and NaHCO3 were assessed. Uniquely, the specific compositions of formulations manufactured and dosed were selected in real-time from emerging clinical data. RESULTS: The study successfully identified a Phase III formulation with a reduced SLS content, which when administered following a low-fat meal, gave comparable pharmacokinetic exposure to the Phase I/II formulation administered under the same conditions. CONCLUSIONS: Our novel 'Make and Test in Parallel' approach enabled optimization of GDC-0810 formulation in a time- and cost-efficient fashion.


Assuntos
Antineoplásicos/farmacocinética , Cinamatos/farmacocinética , Composição de Medicamentos , Excipientes/química , Indazóis/farmacocinética , Administração Oral , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Disponibilidade Biológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Cinamatos/administração & dosagem , Cinamatos/química , Estudos Cross-Over , Feminino , Interações Alimento-Droga , Humanos , Indazóis/administração & dosagem , Indazóis/química , Meglumina/química , Pessoa de Meia-Idade , Receptores de Estrogênio/metabolismo , Dodecilsulfato de Sódio/química , Tensoativos/química
14.
Org Biomol Chem ; 16(31): 5618-5625, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30027979

RESUMO

A novel and efficient methodology concerning the Pd(ii)-catalyzed intermolecular difunctionalization of conjugated dienes is reported to synthesize a series of functionalized morpholines and 2-morpholones. Widely distributed and easily obtained ß-amino alcohols and α-amino acids, as starting nitrogen and oxygen sources, are successfully applied in the difunctionalization of conjugated dienes respectively. The majority of the desired products were obtained in moderate to excellent yields. Oxygen was successfully employed as a terminal oxidant. Further transformation of the generated products allowed for the expansion of structural diversity.

15.
Biomed Chromatogr ; 28(3): 320-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24123161

RESUMO

Capillary gel electrophoresis (CGE) is a powerful tool for the analysis of oligonucleotides owing to its extraordinary resolving power. However, the only feasible injection mode for CGE, electrokinetic injection, can cause bias of the injected amount and thus reproducibility issues for CGE methods. Although the source of the bias in electrokinetic injection for analysis of small molecules by capillary zone electrophoresis has long been identified, there are very few studies on electrokinetic injection issues for biological molecules analyzed by CGE. In this study, we report three issues related to electrokinetic injection for oligonucleotides. First, the relationship between the injection amount and the sample solution resistance is not always linear for oligonucleotides, as has been observed for small molecules. Second, the injecting water prior to an oligonucleotide sample dramatically improves the reproducibility of both the injected amount and resolution through a 'stacking-like' mechanism. Third, optimizing the gel concentration dramatically increases the amount of oligonucleotide that is injected into the column.


Assuntos
Eletroforese Capilar/métodos , Oligonucleotídeos/análise , Oligonucleotídeos/química , Fosfatos/química , Reprodutibilidade dos Testes , Cloreto de Sódio/química , Viscosidade
16.
Int J Biol Macromol ; 256(Pt 1): 127868, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939758

RESUMO

Achieving adhesion of hydrogels to universal materials with desirable strength remains a challenge despite emerging application of hydrogels. Herein we present a mussel foot protein (Mfp) inspired polyelectrolyte hydrogel of poly(ethylenimine)/poly(acrylic acid)-dopamine (PEI/PAADA) developed for universal tough adhesion. The highly-concentrated electrostatic and hydrogen-bonding interactions in PEI/PAADA hydrogel resulted in a tensile strength, strain at break, and toughness of 0.297 MPa, 2784 % and 5.440 MJ m-3, respectively. Moreover, the hydrogel can heal itself from physical damages, even can be recycled after totally dried via rehydration because of the high flexibility and reversibility of its dynamic bonds. Combining the strategies of topological stitching and direct bonding, Mfp-derived catechol and PEI/PAA backbone in PEI/PAADA corporately facilitated robust adhesion of universal materials with shear strength of up to 4.4 MPa and peeling strength of 870 J m-2, which is over 10 times greater than that of commercial fibrin gel. The adhesive also exhibited self-healing capability for at least 5 cycles, good stability in 1 M NaCl solution and characteristic debonding catalyzed by calcium. Moreover, in vitro cell behavior and in vivo wound healing assays suggested the potential of PEI/PAADA as wound dressing.


Assuntos
Bivalves , Hidrogéis , Ácidos Polimetacrílicos , Animais , Hidrogéis/química , Proteínas/química , Adesivos/química
17.
Adv Healthc Mater ; 13(5): e2301870, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38145973

RESUMO

Bone adhesive is a promising candidate to revolutionize the clinical treatment of bone repairs. However, several drawbacks have limited its further clinical application, such as unreliable wet adhesive performance leading to fixation failure and poor biodegradability inhibiting bone tissue growth. By incorporating catechol groups and disulfide bonds into polyurethane (PU) molecules, an injectable and porous PU adhesive is developed with both superior wet adhesion and biodegradability to facilitate the reduction and fixation of comminuted fractures and the subsequent regeneration of bone tissue. The bone adhesive can be cured within a reasonable time acceptable to a surgeon, and then the wet bone adhesive strength is near 1.30 MPa in 1 h. Finally, the wet adhesive strength to the cortical bone will achieve about 1.70 MPa, which is also five times more than nonresorbable poly(methyl methacrylate) bone cement. Besides, the cell culture experiments also indicate that the adhesives show excellent biocompatibility and osteogenic ability in vitro. Especially, it can degrade in vivo gradually and promote fracture healing in the rabbit iliac fracture model. These results demonstrate that this ingenious bone adhesive exhibits great potential in the treatment of comminuted fractures, providing fresh insights into the development of clinically applicable bone adhesives.


Assuntos
Fraturas Cominutivas , Adesivos Teciduais , Animais , Coelhos , Adesivos/química , Poliuretanos/farmacologia , Poliuretanos/química , Cimentos Ósseos/química , Adesivos Teciduais/química
18.
ACS Appl Mater Interfaces ; 15(51): 59826-59837, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38098133

RESUMO

Universal adhesion of hydrogels to diverse materials is essential to their extensive applications. Unfortunately, tough adhesion of wet surfaces remains an urgent challenge so far, requiring robust cohesion strength for effective stress dissipation. In this work, a dual-network hydrogel polyethylenimine-poly(acrylic acid)/alginate (PEI-PAA/Alg) with excellent mechanical strength is realized via PEI-PAA complex and calcium alginate coordination for universal adhesion by the synergistic effort of topological entanglement and catechol chemistry. The dual networks of PEI-PAA/Alg provide mechanically reinforced cohesion strength, which is sufficient for energy dissipation during adhesion with universal materials. After the integration of mussel-inspired dopamine into PAA or Alg, the adhesive demonstrates further improved adhesion performance with a solid adherend and capability to bond cancellous bones. Notably, the dopamine-modified adhesive exhibits better instant adhesion and reversibility with wet surfaces compared with commercial fibrin. Adhesion interfaces are investigated by SEM and micro-FTIR to verify the effectiveness of strategies of topological entanglement. Furthermore, the adhesive also possesses great injectability, stability, tissue adhesion, and biocompatibility. In vivo wound healing and histological analysis indicate that the hydrogel can promote wound closure, epidermis regeneration, and tissue refunctionalization, implying its potential application for bioadhesive and wound dressing.


Assuntos
Adesivos , Adesivos Teciduais , Adesivos/química , Hidrogéis/farmacologia , Hidrogéis/química , Adesivos Teciduais/farmacologia , Adesivos Teciduais/química , Dopamina , Catecóis/química , Alginatos/química
19.
Biomed Chromatogr ; 26(4): 409-18, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21898474

RESUMO

Oligonucleotides have developed into highly versatile and selective therapeutics over the past 20 years. More than five discrete mechanisms of action have been reported and more than 10 different chemical modifications have been used to extend their in vivo half-life and reduce their toxicity. Capillary gel electrophoresis (CGE) has been used extensively for the quantitative analysis of oligonucleotide therapeutics in both preclinical and clinical studies since the 1990s. The success of CGE is based on its extraordinary resolving power, which allows for the simultaneous determination of the parent drug and its metabolites. More recently, capillary gel electrophoresis has seen renewed interest with the emergence of replaceable gels with single-base resolving power and new capillary electrophoresis-mass spectrometry interfaces. This review discusses the bioanalysis of therapeutic oligonucleotides showing the evolution of the field over the past two decades leading to the current new approaches. Included in this review are topics such as different gel types, sample introduction modes, sample extraction procedures, separation conditions and detection methods used in CGE, along with discussions of the successes and limitations associated with each.


Assuntos
Eletroforese Capilar/métodos , Oligonucleotídeos/análise , Animais , Géis/química , Humanos , Oligonucleotídeos/isolamento & purificação , Oligonucleotídeos/metabolismo , Oligonucleotídeos/farmacocinética , Extração em Fase Sólida/métodos
20.
Nanomaterials (Basel) ; 12(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36364506

RESUMO

Semiconductor photocatalysis has received increasing attention because of its potential to address problems related to the energy crisis and environmental issues. However, conventional semiconductor photocatalysts, such as TiO2 and ZnO, can only be activated by ultraviolet light due to their wide band gap. To extend the light absorption into the visible range, the localized surface plasmon resonance (LSPR) effect of noble metal nanoparticles (NPs) has been widely used. Noble metal NPs can couple incident visible light energy to strong LSPR, and the nonradiative decay of LSPR generates nonthermal hot carriers that can be injected into adjacent semiconductor material to enhance its photocatalytic activity. Here we demonstrate that nanoimprint-defined gap plasmonic nanofinger arrays can function as visible light-driven plasmonic photocatalysts. The sub-5 nm gaps between pairs of collapsed nanofingers can support ultra-strong plasmon resonance and thus boost the population of hot carriers. The semiconductor material is exactly placed at the hot spots, providing an efficient pathway for hot carrier injection from plasmonic metal to catalytic materials. This nanostructure thus exhibits high plasmon-enhanced photocatalytic activity under visible light. The hot carrier injection mechanism of this platform was systematically investigated. The plasmonic enhancement factor was calculated using the finite-difference time-domain (FDTD) method and was consistent with the measured improvement of the photocatalytic activity. This platform, benefiting from the precise controllable geometry, provides a deeper understanding of the mechanism of plasmonic photocatalysis.

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