RESUMO
In recent years, there has been a notable rise in the number of patients afflicted with laryngeal diseases, including cancer, trauma, and other ailments leading to voice loss. Currently, the market is witnessing a pressing demand for medical and healthcare products designed to assist individuals with voice defects, prompting the invention of the artificial throat (AT). This user-friendly device eliminates the need for complex procedures like phonation reconstruction surgery. Therefore, in this review, we will initially give a careful introduction to the intelligent AT, which can act not only as a sound sensor but also as a thin-film sound emitter. Then, the sensing principle to detect sound will be discussed carefully, including capacitive, piezoelectric, electromagnetic, and piezoresistive components employed in the realm of sound sensing. Following this, the development of thermoacoustic theory and different materials made of sound emitters will also be analyzed. After that, various algorithms utilized by the intelligent AT for speech pattern recognition will be reviewed, including some classical algorithms and neural network algorithms. Finally, the outlook, challenge, and conclusion of the intelligent AT will be stated. The intelligent AT presents clear advantages for patients with voice impairments, demonstrating significant social values.
Assuntos
Faringe , Voz , Humanos , Som , Algoritmos , Redes Neurais de ComputaçãoRESUMO
Activating surface lattice oxygen (Olatt) through the modulation of metal-oxygen bond strength has proven to be an effective route for facilitating the catalytic degradation of volatile organic compounds (VOCs). Although this strategy has been implemented via the construction of the TM1-O-TM2 (TM represents a transition metal) structure in various reactions, the underlying principle requires exploration when using different TMs. Herein, the Cu2+-O-Fe3+ structure was created by developing CuO-Fe3O4 composites with enhanced interfacial effect, which exhibited superior catalytic activity to their counterparts, with T90 (the temperature of toluene conversion reaching 90%) decreasing by approximately 50 °C. Structural analyses and theoretical calculations demonstrated that the active Cu2+-O-Fe3+ sites at the CuO-Fe3O4 interface improved low-temperature reducibility and oxygen species activity. Particularly, X-ray absorption fine structure spectroscopy revealed the contraction and expansion of Cu-O and Fe-O bonds, respectively, which were responsible for the activation of the surface Olatt. A mechanistic study revealed that toluene can be oxidized by rapid dehydrogenation of methyl assisted by the highly active surface Olatt and subsequently undergo ring-opening and deep mineralization into CO2 following the Mars-van Krevelen mechanism. This study provided a novel strategy to explore interface-enhanced TM catalysts for efficient surface Olatt activation and VOCs abatement.
Assuntos
Cobre , Oxigênio , ToluenoRESUMO
The in vitro conversion of (1S,3S)-1-dimethoxylethyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acid, (1S,3S)-DCCA, in rat plasma is monitored by HPLC-FT-ICR-MS. We show that the in vitro conversion of (1S,3S)-DCCA in rat plasma for 1 h leads to forming (6S/12aS)-bisdimethoxyethylheptachpyridone, reflecting intermolecular condensation of (1S,3S)-DCCA, and the in vitro conversion of (6S/12aS)-bisdimethoxyethylheptachpyridone in rat plasma for 1 h leads to forming (6S/12aS)-heptachpyridone, reflecting hydrolysis of (6S/12aS)-bisdimethoxyethylheptachpyridone. At a dose of 1.0 µmol/kg (6S/12aS)-heptachpyridone orally inhibits venous thrombosis and arterial thrombosis in vivo. Bleeding time, clotting time and international normalized ratio show that at this dose (6S/12aS)-heptachpyridone has no bleeding risk, does not lengthen clotting time and does not change the exogenous coagulation pathway. We also show that the reactions promoted by rat plasma are easy to practice by chemical synthesis. Thus our findings build a bridge across the in vivo conversion and the application.
Assuntos
Carbazóis/uso terapêutico , Dicetopiperazinas/uso terapêutico , Fibrinolíticos/uso terapêutico , Trombose Venosa/tratamento farmacológico , Animais , Sangue/metabolismo , Carbazóis/síntese química , Carbazóis/metabolismo , Dicetopiperazinas/síntese química , Dicetopiperazinas/metabolismo , Fibrinolíticos/síntese química , Fibrinolíticos/metabolismo , Hidrólise , Masculino , Ratos Sprague-Dawley , Veia Cava Inferior/efeitos dos fármacosRESUMO
The clathrin-mediated endocytosis is likely a major mechanism of liposomes' internalization. A kinetic approach was used to assess the internalization mechanism of doxorubicin (Dox) loaded cationic liposomes and to establish physiology-based cell membrane traffic mathematic models. Lipid rafts-mediated endocytosis, including dynamin-dependent or -independent endocytosis of noncaveolar structure, was a dominant process. The mathematic models divided Dox loaded liposomes binding lipid rafts (B) into saturable binding (SB) and nonsaturable binding (NSB) followed by energy-driven endocytosis. The intracellular trafficking demonstrated early endosome-late endosome-lysosome or early/late endosome-cytoplasm-nucleus pathways. The three properties of liposome structures, i.e., cationic lipid, fusogenic lipid, and pegylation, were investigated to compare their contributions to cell membrane and intracellular traffic. The results revealed great contribution of cationic lipid DOTAP and fusogenic lipid DOPE to cell membrane binding and internalization. The valid Dox in the nuclei of HepG2 and A375 cells treated with cationic liposomes containing 40mol% of DOPE were 1.2-fold and 1.5-fold higher than that in the nuclei of HepG2 and A375 cells treated with liposomes containing 20mol% of DOPE, respectively, suggesting the dependence of cell type. This tendency was proportional to the increase of cell-associated total liposomal Dox. The mathematic models would be useful to predict intracellular trafficking of liposomal Dox.
Assuntos
Doxorrubicina/análogos & derivados , Endocitose/fisiologia , Microdomínios da Membrana/fisiologia , Modelos Biológicos , Transporte Biológico , Cátions , Linhagem Celular , Doxorrubicina/administração & dosagem , Doxorrubicina/metabolismo , Ácidos Graxos Monoinsaturados/química , Células Hep G2 , Humanos , Lipossomos , Fusão de Membrana , Lipídeos de Membrana/química , Microscopia de Fluorescência , Fosfatidiletanolaminas/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/metabolismo , Compostos de Amônio Quaternário/químicaRESUMO
In GPIIb/IIIa mediated arterial thrombosis platelet activation plays a central role. To discover platelet activation inhibitor the pharmacophores of GPIIb/IIIa receptor inhibitors and anti-thrombotic agents were analyzed. This led to the design of (1R,3S)- and (1S,3S)-1-methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acids as GPIIb/IIIa inhibitors. Comparing to (1S,3S)-isomer (1R,3S)-isomer had lower cdocker interaction energy. AFM image showed that the minimal effective concentration of (1S,3S)-isomer and (1R,3S)-isomer inhibiting platelet activation were 10-5â¯M and 10-6â¯M, respectively. In vivo 1⯵mol/kg of oral (1S,3S)-isomer effectively inhibited the rats to form arterial thrombus and down regulated GPIIb/IIIa expression, but the activities were significantly lower than those of 1⯵mol/kg of oral (1R,3S)-isomer. Both (1S,3S)-isomer and (1R,3S)-isomer can be safely used for structural modifications, but (1R,3S)-isomer should be superior to (1S,3S)-isomer.
Assuntos
Desenho de Fármacos , Inibidores da Agregação Plaquetária/química , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Tiazóis/química , Administração Oral , Animais , Sítios de Ligação , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Microscopia de Força Atômica , Simulação de Acoplamento Molecular , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Estrutura Terciária de Proteína , Ratos , Estereoisomerismo , Termodinâmica , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Trombose/tratamento farmacológicoRESUMO
By docking 126 derivatives of ß-carboline-3-carboxylic acid, tetrahydro-ß-carboline-3-carboxylic acid and indoloquinolizine into the active pocket of P-selectin (2-(3-(hydroxymethyl)-9H-pyrido[3,4-b]indol-1-yl)ethyl)-l-phenylalanine (HMCEF) was assigned a novel inhibitor. ELISA and flow cytometry experiments showed that HMCEF effectively down-regulated P-selectin expression and supported the rationality of the computer assistant screening, while UV spectrum experiments demonstrated that HMCEF directly bound to P-selectin. In vivo HMCEF dose dependently inhibited the rats and mice to form thrombus and had a minimal effective dose of 20nmol/kg, dose dependently inhibited inflammatory response of mice and had a minimal effective dose of 20nmol/kg. The decrease of serum TNFα and IL-8 of the treated mice was proposed to be the action mechanism of HMCEF inhibiting thrombosis and inflammation. All data imply that HMCEF is a novel lead of P-selectin inhibitor.
Assuntos
Indóis/farmacologia , Selectina-P/antagonistas & inibidores , Fenilalanina/análogos & derivados , Animais , Relação Dose-Resposta a Droga , Descoberta de Drogas , Ensaio de Imunoadsorção Enzimática , Indóis/síntese química , Indóis/química , Camundongos , Fenilalanina/síntese química , Fenilalanina/química , Fenilalanina/farmacologia , Ratos , Espectrofotometria UltravioletaRESUMO
PURPOSE: Recurrent ischemic events in Chinese patients with symptomatic extracranial or intracranial stenosis caused by aspirin or clopidogrel resistance are well known. We aimed to identify the contribution of genetic variants to the events. METHODS: Patients with symptomatic extracranial or intracranial stenosis receiving dual antiplatelet treatment for at least 5 days were enrolled in this study. The primary endpoint was a composite of ischemic events, including recurrent transient ischemic attack, stroke, myocardial infarction, and vascular-related mortality. Twenty-four single nucleotide polymorphisms (SNPs) were assessed and genotyped. The clinical characteristics of enrolled patients were collected from medical records. The influence of genetic polymorphisms on the recurrent ischemic events of the patients was examined. RESULTS: A total of 377 patients were included. During a 12-month follow-up, the composite primary endpoint was observed in 64 patients. The CYP2C19*3 (rs4986893) may increase the occurrence of the primary composite endpoint (OR = 2.56, 95 % CI = 1.29-5.10, P = 0.007), and the mutation of CES1 rs8192950 was associated with the decreased recurrence of ischemic events (OR = 0.53, 95 % CI = 0.30-0.94, P = 0.029). The other SNPs that were tested did not have statistically significant associations with the composite endpoint. CONCLUSIONS: For Chinese patients with symptomatic extracranial or intracranial stenosis treated with clopidogrel, CYP2C19*3 mutation was associated with an increased risk of ischemic events, and the mutation of rs8192950 in CES1 is associated with a decreased risk of recurrent ischemic events. Testing these two SNPs could be of value in the identification of patients at risk for recurrent ischemic events.
Assuntos
Aspirina/uso terapêutico , Hidrolases de Éster Carboxílico/genética , Constrição Patológica/genética , Citocromo P-450 CYP2C19/genética , Isquemia/genética , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina/análogos & derivados , Idoso , Povo Asiático/genética , Clopidogrel , Constrição Patológica/tratamento farmacológico , Feminino , Genótipo , Humanos , Isquemia/prevenção & controle , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Ticlopidina/uso terapêutico , Resultado do TratamentoRESUMO
Inflammation has a critical role in the tumor progression, free radical damage can worse the status of patients in cancer condition. The anti-cancer agents capable of inhibiting inflammation and scavenging free radicals attract a lot of our interest. Aimed at the discovery of such anti-tumor agent, a novel intercalator, benzyl 1-[4-hydroxy-3-(methoxycarbonyl)-phenyl-9H-pyrido[3,4-b]indole-3-carboxylate (BPIC) was presented. The docking investigation of BPIC and doxorubicin towards the DNA (PDB ID: 1NAB) gave equal score and similar feature. The anti-proliferation assay of 8 cancer cells identified S180 cells had equal sensitivity to BPIC and doxorubicin. The anti-tumor assay defined the efficacy of BPIC been 2 folds higher than that of doxorubicin. At 1µmol/kg of dose BPIC effectively inhibited xylene-induced ear edema and decreased the plasma TNF-α and IL-8 of the mice. BPIC scavenged âOH, âO2(-) and NO free radicals in a concentration dependent manner and NO free radicals had the highest sensitivity. BPIC could be a novel anti-tumor lead capable of simultaneously inhibiting inflammation and scavenging free radicals.
Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Carbolinas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Inflamação/tratamento farmacológico , Substâncias Intercalantes/farmacologia , Neoplasias/tratamento farmacológico , Salicilatos/farmacologia , Animais , Anti-Inflamatórios/química , Antineoplásicos/química , Carbolinas/química , Linhagem Celular Tumoral , Sequestradores de Radicais Livres/química , Radicais Livres/imunologia , Humanos , Inflamação/imunologia , Substâncias Intercalantes/química , Camundongos , Simulação de Acoplamento Molecular , Neoplasias/imunologia , Salicilatos/químicaRESUMO
Compound 6, a novel isoquinoline comprising two isoquinoline-3-carboxylic acids and a benzoic acid conjugated together using tris(2-aminoethyl)amine, was synthesized and tested for anti-tumor activity. In vivo evaluations found 6 to be well tolerated, of high therapeutic efficacy and of low systemic toxicity, at effective doses. The results suggest 6 to be a promising lead for future study, and the use of multiple isoquinoline-3-carboxylic acid moieties as pharmacophores in the same molecule to be a useful strategy for the design of anti-tumor drugs.
Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Isoquinolinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Benzoatos/síntese química , Benzoatos/química , Benzoatos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Isoquinolinas/síntese química , Isoquinolinas/química , Camundongos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Relação Estrutura-AtividadeRESUMO
1,2,3,4,6-Penta-O-galloyl-ß-D-glucose (PGG) inhibits glioma cancer U251 cells, more strongly than MDA-MB-231 and U87 cells. In addition, PGG is transported across cancer cell membrane to further down-regulate FAS and activate caspase-3 in MDA-MB-231 cells. Compared with other FAS inhibitors, including catechin gallate and morin, PGG involves a higher reversible fast-binding inhibition with half-inhibitory concentration value (IC50) of 1.16 µM and an irreversible slow-binding inhibition, i.e. saturation kinetics with a dissociation constant of 0.59 µM and a limiting rate constant of 0.16 min(-l). The major reacting site of PGG is on the ß-ketoacyl reduction domain of FAS. PGG exhibits different types of inhibitions against the three substrates in the FAS overall reaction. The higher concentrations of PGG tested (higher than 20 µM) clearly altered the secondary structure of FAS by increasing the α-helix and induced a redshift in the FAS spectra. In addition, only PGG concentrations higher than 20 µM resulted in FAS precipitation.
Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Ácido Graxo Sintases/antagonistas & inibidores , Taninos Hidrolisáveis/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias/genéticaRESUMO
BACKGROUND: In recent years, nanomaterials-based pesticide carriers have garnered significant attention and sparked extensive research. However, most studies have primarily focused on investigating the impact of physical properties of nanomaterials, such as size and modifiable sites, on drug delivery efficiency of nano-pesticides. The limited exploration of biologically active nanomaterials poses a significant obstacle to the advancement and widespread adoption of nano-pesticides. In this study, we prepared chitin nanocrystals (ChNC) based on acid hydrolysis and systematically investigated the differences between nano- and normal chitin against plant bacteria (Pseudomonas syringae pv. tabaci). The primary objective was to seek out nanocarriers with heightened biological activity for the synthesis of nano-pesticides. RESULTS: Zeta potential analysis, Fourier Transform infrared spectrometry (FTIR), X-Ray diffraction (XRD), Atomic force microscopy (AFM) and Transmission electron microscopy (TEM) identified the successful synthesis of ChNC. ChNC showcased remarkable bactericidal activity at comparable concentrations, surpassing that of chitin, particularly in its ability to inhibit bacterial biofilm formation. Furthermore, ChNC displayed heightened effectiveness in disrupting bacterial cell membranes, resulting in the leakage of bacterial cell contents, structural DNA damage, and impairment of DNA replication. Lastly, potting experiments revealed that ChNC is notably more effective in inhibiting the spread and propagation of bacteria on plant leaves. CONCLUSION: ChNC exhibited higher antibacterial activity compared to chitin, enabling efficient control of plant bacterial diseases through enhanced interaction with bacteria. These findings offer compelling evidence of ChNC's superior bacterial inhibition capabilities, underscoring its potential as a promising nanocarrier for nano-pesticide research. © 2023 Society of Chemical Industry.
Assuntos
Nanopartículas , Praguicidas , Quitina , Estudos de Viabilidade , Nanopartículas/química , Antibacterianos/farmacologia , AgriculturaRESUMO
The application of antiplant virus agents on leaf surfaces faces challenges due to their vulnerability to wear, instability, and limited duration, which in turn jeopardizes plant health and yield. In recent years, high-aspect-ratio nanomaterials have gained prominence as powerful carriers for disease treatment, thanks to their exceptional penetrability and precise drug delivery capabilities. Here, we synthesized a pH-responsive nanoimmune inducer (CNC-AMO) with strong leaf adhesion through a Schiff base reaction, achieved by grafting amino-oligosaccharides (AMOs) on the surface of aldehyde-based CNC (CNC-CHO). Fourier transform infrared spectrometry, zeta potential, X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, atomic force microscopy, scanning electron microscopy, thermogravimetric analysis, and elemental analysis were used to characterize the CNC-AMO. The CNC-AMO displayed the capability for pH-responsive AMO release, showcasing its potential for targeted and controlled delivery. When applied to plants, the CNC-AMO exhibited impressive anti-TMV efficacy during a weeklong observation period. Meanwhile, the CNC-AMO exhibited remarkable adhesion and scouring resistance on the surfaces of the plant leaves. We strongly believe that the synergy of environmentally friendly synthetic materials, efficient plant virus control, and streamlined scalability positions CNC-AMOs as a promising pesticide for plant virus therapy.
Assuntos
Celulose , Nanopartículas , Celulose/química , Espectrofotometria Infravermelho , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Concentração de Íons de HidrogênioRESUMO
Chitin is a kind of natural nitrogenous organic polysaccharide. It contains antibacterial and antiviral properties, and it can induce plant disease resistance and promote plant growth. However, its application is constrained due to its insolubility and intricate molecular structure. Tobacco mosaic disease is caused by tobacco mosaic virus (TMV) infection, which seriously harms tobacco production. Zinc-containing chemical agents are commonly used to control tobacco mosaic disease, but overuse of chemical agents will cause serious environmental pollution. In this study, a novel nanomaterial (ChNC@Zn) was prepared by using chitin nanocrystals loaded with Zn2+, which has the function of inducing disease resistance to plants and reducing virus activity. When the Zn2+ concentration of ChNC@Zn is 105.6 µg/mL, it shows higher resistance to TMV than Lentinan (LNT). ChNC@Zn can improve the enzymes activities of peroxidase (POD) and catalase (CAT) in tobacco, and reduce the damage of reactive oxygen species (ROS) caused by TMV infection, thereby inducing resistance to TMV in tobacco. Besides, it can promote the growth of tobacco. As a result, ChNC@Zn can exhibit strong antiviral activity at low Zn2+ concentration and minimize the pollution of Zn2+ to the environment, which has high potential application value in the control of virus disease.
RESUMO
To increase the metal selectivity of polyaspartic acid, a so-called green chelant, poly-α,ß-dl-aspartyl-l-methionine (PDM) was synthesized as a novel lead chelating agent. The phosphoric acid (80%) catalyzed thermal poly condensation of dl-aspartic acid provided poly succinimide, which was amidated with l-methionine to form PDM (MW: 29161). At the doses of 0.1, 1.0, and 10.0 nmol/kg, either by intraperitoneal injection (i.p.) or oral administration, PDM removed Pb from the spleens, hearts, and kidneys of mice, especially dose-dependently decreasing the accumulation of Pb in the brains, livers, and femurs of the mice, and did not interfere with the essential metals, including Cu, Fe, Mn, and Ca. Even at the dose of 0.1 nmol/kg, the i.p. injection of PDM removed Pb from the spleens, hearts, and kidneys of mice and increased the amount of urinary volume and urinary Pb, and the amount of fecal matter and the amount of fecal Pb, resulting in effective removal of Pb from the body of mice given Pb by i.p. injection. Our findings revealed that in aqueous solution PDM formed diverse nanospecies.
Assuntos
Quelantes/farmacologia , Poluentes Ambientais/farmacocinética , Chumbo/farmacocinética , Peptídeos/farmacologia , Animais , Encéfalo/metabolismo , Poluentes Ambientais/sangue , Fezes/química , Fêmur/metabolismo , Rim/metabolismo , Chumbo/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Miocárdio/metabolismo , Peptídeos/síntese química , Baço/metabolismoRESUMO
Poly-α,ß-DL-aspartic acid is known as a green chelant of various metal ions. To provide a novel nanochelant for treating Pb(II) poisoning, poly-α,ß-DL-aspartic acid was modified with L-Cys to form poly-α,ß-DL-aspartyl-L-cysteine (PDC; MW, 27273). DL-Asp was converted into polysuccinimide through a thermal polycondensation, and the amidation of polysuccinimide with L-Cys provided PDC. In water, PDC formed various porous nanospecies. In the mouse lead intoxication model, both intraperitoneal and oral administration of PDC (0.1, 1.0, and 10.0 nmol/kg) dose dependently removed Pb(II) accumulated in the organ, bone, and blood. PDC did not remove the essential metals including Cu(2+), Fe(2+), Mn(2+), Zn(2+), and Ca(2+) of the treated mice. The porous feature and size of the pH- and concentration-dependent nanospecies of PDC benefited the removal of Pb(II).
Assuntos
Complexos de Coordenação/química , Cisteína/análogos & derivados , Chumbo/química , Nanoestruturas/química , Peptídeos/química , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Complexos de Coordenação/metabolismo , Fezes/química , Concentração de Íons de Hidrogênio , Chumbo/urina , Masculino , Camundongos , Peptídeos/síntese química , Porosidade , Distribuição TecidualRESUMO
The modification of 3S-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQA) with ß-cyclodextrin (ß-CD) provides an oral antithrombotic agent, 6-(3'S-isoquinoline-3'-carboxylaminoethylamino)-6-deoxy-ß-CD (THIQA-ß-CD). In aqueous solution THIQA-ß-CD undergoes intermolecular inclusion complexation and forms pH-dependent nanostructures. The morphological feature of THIQA-ß-CD is a nanocloud consisting of numerous particles that are 5 nm-6 nm in diameter at pH 3.0. The nanocloud switches to a nanorod ranging from 100 nm to 385 nm in length at pH 7.2, then to nanowires of 50 nm to 530 nm in length at pH 10.1. THIQA-ß-CD, which has unusual nanostructures, offers enhanced stability in blood. Inhibition of thrombin-induced platelet aggregation in vitro and demonstrated antithrombotic efficacy in vivo. This investigation demonstrated that the modification of THIQA with ß-CD is a promising approach for clinical therapy of thrombus disease. The pH-dependent nanostructures of conjugate provide the desired in vivo antithrombotic activity and in vitro stability in blood. FROM THE CLINICAL EDITOR: This study a demonstrates that the modification of 3S-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQA) with beta-cyclodextrin, which leads to pH dependent nanostructure formation, is a promising approach for clinical therapy of thrombotic disease.
Assuntos
Anticoagulantes/uso terapêutico , Nanoestruturas/uso terapêutico , Tetra-Hidroisoquinolinas/uso terapêutico , Trombose/tratamento farmacológico , beta-Ciclodextrinas/uso terapêutico , Animais , Anticoagulantes/química , Anticoagulantes/farmacologia , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Masculino , Nanoestruturas/química , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Ratos , Ratos Wistar , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacologia , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologiaRESUMO
1-[(Anthracen-9-yl)methylene] thiosemicarbazide shows weak fluorescence due to a photo-induced electron transfer (PET) process from the thiosemicarbazide moiety to the excited anthracene. The anthracene emission can be recovered via protonation of the amine as the protonated aminomethylene as an electron-withdrawing group that suppresses the PET process. Similarly, chelation between the ligand and the metal ions can also suppress the PET process and results in a fluorescence enhancement (CHEF). When solvents are introduced as the third control, a molecular 2:1 multiplexer is constructed to report selectively the inputs. Therefore, a molecular 2:1 multiplexer is realized in a simple molecular system.
Assuntos
Semicarbazidas/química , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria UltravioletaRESUMO
Thrombin is the most potent platelet aggregator. To discover the selective inhibitor of thrombin that is important to curing platelet aggregation-related diseases, docking experiments were performed to dock (1R,3S)-2,3,4,9-tetrahydro-ß-carboline-3- carboxylic acid, [(1R,3S)-THCCA], and (1S,3S)-2,3,4,9-tetrahydro-ß-carboline-3- carboxylic acid, [(1S,3S)-THCCA], into the p pocket of bovine thrombin. The ideal match supported that (1R,3S)-THCCA could be used as a potential lead compound. In this case 20 natural amino acids were theoretically introduced into the 3-carboxyl of (1R,3S)-THCCA and 20 derivatives, (1R,3S)-THCCA-amino acids, were docked into p pocket of bovine thrombin to perform virtual screening. The screening revealed that comparing to (1R,3S)-THCCA itself the DockScores of 16 derivatives were higher, and (1R,3S)-THCCA-Asn (4j) got the highest DockScore. Thus, 16 derivatives were synthesized for experimental study. The in vitro anti-platelet aggregation assay showed that at 100 µM of concentration the 16 derivatives failed to inhibit the platelet aggregation induced by both adenosine diphosphate and arachidonic acid. On the other hand, however, the IC50 value of the 16 derivatives inhibiting the platelet aggregation induced by platelet activating factor and thrombin ranged from 9.44 µM to 194.64 µM and from 0.07 µM to 9.56 µM, respectively. The in vitro anti-platelet aggregation assay suggested that the 16 derivatives selectively inhibited the platelet aggregation induced by thrombin. In particular, the IC50 of (1R,3S)-THCCA-Asn (4j) had the lowest value. On rat model at 1 nmol/kg of dosage the 16 derivatives effectively prevented thrombus formation. It is worth pointing out that even at 0.01 nmol/kg of dosage, 4j still effectively prevented thrombus formation. 4j hardly has effects on the proliferation of mammalian cells and rat tail bleeding time. In conclusion, the combination of virtual screening and biological assays successfully lead to the discovery of 4j as a promising candidate of selective inhibitor of thrombin.
Assuntos
Trombina , Trombose , Difosfato de Adenosina/metabolismo , Difosfato de Adenosina/farmacologia , Aminoácidos/química , Animais , Ácidos Araquidônicos , Bioensaio , Plaquetas , Ácidos Carboxílicos/farmacologia , Bovinos , Mamíferos , Fator de Ativação de Plaquetas/metabolismo , Fator de Ativação de Plaquetas/farmacologia , Inibidores da Agregação Plaquetária/química , Ratos , Trombina/metabolismo , Trombose/metabolismoRESUMO
The coupling of the 1-carboxyl of DMSA with l-amino acids led to a class of novel 1-(carbonyl-l-amino-acid)-2,3-dimercaptosuccinic acids (DMSA--amino acid conjugates, DMSA-Gly, -Ser, -Val, -Leu, -Ile, -Asn, -Asp, -Gln, -Glu, -Met, -Phe, and -Trp). In the in vivo evaluation of Pb-loaded mice, 0.4 mmol/kg of the conjugates effectively decreased the Pb levels of the femur, brain, kidney, liver, and blood, greatly enhanced urination, and increased the Pb levels of both urine and feces, while causing no redistributions of Pb to the other organs, especially to the brain. With respect to lowering the bone and brain Pb, DMSA-Ile, -Asn, -Gln, and -Met were more effective than DMSA. This benefit was attributed to their high transmembrane ability. In contrast to Pb, the essential metals such as Fe, Cu, Zn, and Ca of the treated mice were not affected by the administration of the conjugates. Silico molecular modeling predicted that the conjugates had little hepatotoxicity, except possibly for DMSA-Phe.
Assuntos
Aminoácidos/química , Aminoácidos/uso terapêutico , Antídotos/química , Antídotos/uso terapêutico , Intoxicação por Chumbo/tratamento farmacológico , Succímero/química , Succímero/uso terapêutico , Sequência de Aminoácidos , Animais , Chumbo/farmacocinética , Chumbo/toxicidade , Masculino , CamundongosRESUMO
By linking the mercapto groups with isopropyl and introducing L-amino acid into the 5-carboxyl of DMSA a class of novel 5-(1-carbonyl-L-amino-acid)-2,2- dimethyl-[1,3]dithiolane-4-carboxylic acids were prepared. Their in vivo activities were evaluated on lead loaded mice at the dose of 0.4 mmol/kg. The results showed that the lead levels of the livers, kidneys, femurs and brains in particular could be efficiently decreased by 0.4 mmol/kg of 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids. The benefit of 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids to the detoxification of the brain lead was attributed to their transmembrane ability. Compared with the lead detoxification efficacy, they did not affect the essential metals such as Fe, Cu, Zn, and Ca of the treated mice. Silico molecular modeling predicted that 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids had no hepatotoxicity.