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1.
Artigo em Inglês | MEDLINE | ID: mdl-38658392

RESUMO

PURPOSE: Prostate-specific membrane antigen (PSMA) is a promising target for diagnosis and radioligand therapy (RLT) of prostate cancer. Two novel PSMA-targeting radionuclide therapy agents, [177Lu]Lu-P17-087, and its albumin binder modified derivative, [177Lu]Lu-P17-088, were evaluated in metastatic castration-resistant prostate cancer (mCRPC) patients. The primary endpoint was dosimetry evaluation, the second endpoint was radiation toxicity assessment (CTCAE 5.0) and PSA response (PCWG3). METHODS: Patients with PSMA-positive tumors were enrolled after [68Ga]Ga-PSMA-11 PET/CT scan. Five mCRPC patients received [177Lu]Lu-P17-087 and four other patients received [177Lu]Lu-P17-088 (1.2 GBq/patient). Multiple whole body planar scintigraphy was performed at 1.5, 4, 24, 48, 72, 120 and 168 h after injection and one SPECT/CT imaging was performed at 24 h post-injection for each patient. Dosimetry evaluation was compared in both patient groups. RESULTS: Patients showed no major clinical side-effects under this low dose treatment. As expected [177Lu]Lu-P17-088 with longer blood circulation (due to its albumin binding) exhibited higher effective doses than [177Lu]Lu-P17-087 (0.151 ± 0.036 vs. 0.056 ± 0.019 mGy/MBq, P = 0.001). Similarly, red marrow received 0.119 ± 0.068 and 0.048 ± 0.020 mGy/MBq, while kidney doses were 0.119 ± 0.068 and 0.046 ± 0.022 mGy/MBq, respectively. [177Lu]Lu-P17-087 demonstrated excellent tumor uptake and faster kinetics; while [177Lu]Lu-P17-088 displayed a slower washout and higher average dose (7.75 ± 4.18 vs. 4.72 ± 2.29 mGy/MBq, P = 0.018). After administration of [177Lu]Lu-P17-087 and [177Lu]Lu-P17-088, 3/5 and 3/4 patients showed reducing PSA values, respectively. CONCLUSION: [177Lu]Lu-P17-088 and [177Lu]Lu-P17-087 displayed different pharmacokinetics but excellent PSMA-targeting dose delivery in mCRPC patients. These two agents are promising RLT agents for personalized treatment of mCRPC. Further studies with increased dose and frequency of RLT are warranted to evaluate the potential therapeutic efficacy. TRIAL REGISTRATION: 177Lu-P17-087/177Lu-P17-088 in Patients with Metastatic Castration-resistant Prostate Cancer (NCT05603559, Registered at 25 October, 2022). URL OF REGISTRY: https://classic. CLINICALTRIALS: gov/ct2/show/NCT05603559 .

2.
J Med Chem ; 67(6): 4793-4803, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38450559

RESUMO

Bone metastasis in cancer patients is a major disease advancement for various types of cancer. Previously, [68Ga]Ga-HBED-CC-bisphosphonate ([68Ga]Ga-P15-041) showed excellent bone uptake and efficient detection of bone metastasis in patients. To accommodate different α- or ß--emitting metals for radionuclide therapy, a novel DOTA-HBED-CC-bisphosphonate (P15-073, 1) was prepared and the corresponding [68Ga]Ga-1 and [177Lu]Lu-1 were successfully synthesized in high yields and purity. Gallium-68 conjugation to HBED-CC at room temperature and lutetium-177 conjugation to DOTA at 95 °C were verified in model compounds through secondary mass confirmation. These bisphosphonates, [68Ga]Ga-1 and [177Lu]Lu-1, displayed high binding affinity to hydroxyapatite in vitro. After an iv injection, it showed excellent uptake in the spine of normal mice, and micro-PET/CT imaging of nude mice model of bone metastasis showed high bone uptake in tumor tissue. The results indicated that [68Ga]Ga/[177Lu]Lu-1 holds promise as a theranostic radioligand agent for managing cancer bone metastases.


Assuntos
Neoplasias Ósseas , Ácido Edético/análogos & derivados , Radioisótopos de Gálio , Compostos Heterocíclicos com 1 Anel , Humanos , Camundongos , Animais , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Difosfonatos/uso terapêutico , Medicina de Precisão , Camundongos Nus , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico
3.
BMC Chem ; 17(1): 183, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104171

RESUMO

Carbapenem-resistant Enterobacterales (CRE) has emerged as a worldwide spread nosocomial superbug exhibiting antimicrobial resistance (AMR) to all current antibiotics, leaving limited options for treating its infection. To discovery novel antibiotics against CRE, we designed and synthesized a series of 14 isothiazol-3(2H)-one analogues subjected to antibacterial activity evaluation against Escherichia coli (E. coli) BL21 (NDM-1) and clinical strain E. coli HN88 for investigating their structure-activity relationships (SAR). The results suggested that 5-chloroisothiazolone core with an N-(4-chlorophenyl) substitution 5a was the most potent antibacterial activity against the E. coli BL21 (NDM-1) with MIC value of less than 0.032 µg/mL, which was at least 8000-fold higher than the positive control Meropenem (MRM). It also displayed 2048-fold potent than the positive control MRM against E. coli HN88. Additionally, SAR analysis supported the conclusion that compounds with a chloro-group substituted on the 5-position of the heterocyclic ring was much more potent than other positions. The board spectrum analysis suggested that compound 5a showed a promising antimicrobial activity on MRSA and CRE pathogens. Meanwhile, cytotoxicity study of compound 5a suggested that it had a therapeutic index value of 875, suggesting future therapeutic potential. In vivo efficacy study declared that compound 5a could also protect the BALB/c mice against American type culture collection (ATCC) 43,300. Further screening of our compounds against a collection of CRE strains isolated from patients indicated that compound 5 g displayed much stronger antibacterial activity compared with MRM. In conclusion, our studies indicated that isothiazolones analogues could be potent bactericidal agents against CRE and MRSA pathogens.

4.
Molecules ; 28(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37959836

RESUMO

Malignant cardiac arrhythmias with high morbidity and mortality have posed a significant threat to our human health. Scutellarein, a metabolite of Scutellarin which is isolated from Scutellaria altissima L., presents excellent therapeutic effects on cardiovascular diseases and could further be metabolized into methylated forms. A series of 22 new scutellarein derivatives with hydroxyl-substitution based on the scutellarin metabolite in vivo was designed, synthesized via the conjugation of the scutellarein scaffold with pharmacophores of FDA-approved antiarrhythmic medications and evaluated for their antiarrhythmic activity through the analyzation of the rat number of arrhythmia recovery, corresponding to the recovery time and maintenance time in the rat model of barium chloride-induced arrhythmia, as well as the cumulative dosage of aconitine required to induce VP, VT, VF and CA in the rat model of aconitine-induced arrhythmia. All designed compounds could shorten the time of the arrhythmia continuum induced by barium chloride, indicating that 4'-hydroxy substituents of scutellarein had rapid-onset antiarrhythmic effects. In addition, nearly all of the compounds could normalize the HR, RR, QRS, QT and QTc interval, as well as the P/T waves' amplitude. The most promising compound 10e showed the best antiarrhythmic activity with long-term efficacy and extremely low cytotoxicity, better than the positive control scutellarein. This result was also approved by the computational docking simulation. Most importantly, patch clamp measurements on Nav1.5 and Cav1.2 channels indicated that compound 10e was able to reduce the INa and ICa in a concentration-dependent manner and left-shifted the inactivation curve of Nav1.5. Taken together, all compounds were considered to be antiarrhythmic. Compound 10e even showed no proarrhythmic effect and could be classified as Ib Vaughan Williams antiarrhythmic agents. What is more, compound 10e did not block the hERG potassium channel which highly associated with cardiotoxicity.


Assuntos
Aconitina , Antiarrítmicos , Ratos , Humanos , Animais , Aconitina/farmacologia , Antiarrítmicos/efeitos adversos , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico
5.
J Med Chem ; 66(17): 12602-12613, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37670407

RESUMO

Prostate-specific membrane antigen (PSMA) is an excellent target for imaging and radionuclide therapy of prostate cancer. Recently, [177Lu]Lu-PSMA-617 (Pluvicto) was approved by the FDA for radionuclide therapy. To develop hetero-bivalent agents targeting both PSMA and bone metastasis, [177Lu]Lu-P17-079 ([177Lu]Lu-1) and [177Lu]Lu-P17-081 ([177Lu]Lu-2) were prepared. In vivo biodistribution studies of [177Lu]Lu-PSMA-617, [177Lu]Lu-1, and [177Lu]Lu-2 in mice bearing PC3-PIP (PSMA positive) tumor showed high uptake in PSMA-positive tumor (14.5, 14.7, and 11.3% ID/g at 1 h, respectively) and distinctively different bone uptakes (0.52, 6.52, and 5.82% ID/g at 1 h, respectively). PET imaging using [68Ga]Ga-P17-079 ([68Ga]Ga-1) in the same mouse model displayed excellent images confirming the expected dual-targeting to PSMA-positive tumor and bone. Results suggest that [177Lu]Lu-P17-079 ([177Lu]Lu-1) is a promising candidate for further development as a hetero-bivalent radionuclide therapy agent targeting both PSMA expression and bone metastases for the treatment of prostate cancer.


Assuntos
Neoplasias Ósseas , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Radioisótopos/uso terapêutico , Lutécio/uso terapêutico , Radioisótopos de Gálio , Distribuição Tecidual , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico
6.
Polymers (Basel) ; 15(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37177149

RESUMO

According to the demand for high-performance fibers for high-latitude ocean exploration and development, this paper selects representative products of high-performance liquid crystal fibers: thermotropic liquid crystal polymer fibers (TLCP) and poly p-phenylene terephthalamide (PPTA) fibers. Through a series of freeze-thaw (F-T) experiments for simulating a real, cold marine environment, we then measure the retention of mechanical properties of these two kinds of fibers. Before that, due to the difference in their chemical structures, we tested their Yang-Laplace contact angle (YLCA) and water absorption; the results suggested that PPTA fibers would absorb more moisture. Surprisingly, then, compared with thermotropic liquid crystal polymer (TLCP) fibers, the retention of the mechanical properties of poly p-phenylene terephthalamide (PPTA) fibers decreased by around 25% after the F-T experiments. The Fourier-transformed infrared (FT-IR) analysis, the attenuated total reflection (ATR) accessory analysis and the degree of crystal orientation measured by two-dimensional wide-angle X-ray diffraction (2D-WAXD) confirm that no changes in the chemical and the orientation structure of the crystal region of the fibers occurred after they underwent the F-T cycles. However, as observed by scanning electron microscopy (SEM), there are microcracks of various extents on the surface of the PPTA fibers, but they do not appear on the surface of TLCP fibers. It is obvious that these microcracks will lead to the loss of mechanical properties; we infer that the moisture absorbed by the PPTA fibers freezes below the freezing point, and the volume expansion of the ice causes the collapse of the microfibrillar structure. The two sorts of fibers subjected to the F-T experiments are immersed in a sodium chloride solution, and the amount of water infiltrated into the PPTA microfibrillar structure is evaluated according to the content of sodium ions in the fiber surface and subsurface layers through X-ray spectroscopy (EDS) elemental analysis. From the above analysis, we found that TLCP fibers can more effectively meet the operating standards of the severe and cold marine environment.

7.
Mol Pharm ; 20(4): 2159-2169, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36942924

RESUMO

Fibroblast activation protein (FAP) is selectively expressed in tumors and highly important for maintaining the microenvironment in malignant tumors. Radioisotope-labeled FAP inhibitors (FAPIs) were proven to be useful for diagnosis and radionuclide therapy of cancer and are under active clinical investigations. Ga-HBED complex displays a higher in vivo stability constant (log KGaL: 38.5), compared to that of Ga-DOTA (log KGaL: 21.3). Such advantage in stability constant suggests that it may be useful for development of alternative FAPI imaging agents. In this study, previously reported [68Ga]Ga-DOTA-FAPI-02 and -04 were converted to the corresponding [68Ga]Ga-HBED-CC-FAPI-02 and -04 derivatives ([68Ga]Ga-4, [68Ga]Ga-5, [68Ga]Ga-6, and [68Ga]Ga-7). It was found that substituting the DOTA chelating group with HBED-CC led to several unique and desirable tumor-targeting properties: (1) robust, fast, and high yield labeling─readily adaptable to a kit formulation; (2) high stabilities in vitro; (3) excellent FAP binding affinities (IC50 ranging between 4 and 7 nM) and improved cell uptake and retention (in HT1080 (FAP+) cells); and (4) excellent selective in vivo tumor uptake in nude mice bearing U87MG tumor. It appeared that Ga(III) chelation with HBED-CC improved the in vivo kinetics favoring higher tumor uptake and retention compared to the corresponding Ga-DOTA complex. Out of the four tested ligands the new [68Ga]Ga-HBED-CC-FAPI dimer, [68Ga]Ga-6, displayed the best tumor localization properties, and further studies are warranted to demonstrate that it is an alternative FAP imaging agent for cancer patients.


Assuntos
Radioisótopos de Gálio , Tomografia por Emissão de Pósitrons , Animais , Camundongos , Radioisótopos de Gálio/química , Tomografia por Emissão de Pósitrons/métodos , Camundongos Nus , Linhagem Celular Tumoral , Quelantes , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
8.
Carbohydr Polym ; 280: 119009, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35027122

RESUMO

In this study, a kind of polymeric ionic liquid (PIL) called PIL-Cl was synthesized and modified to obtain conductive graphene coated carboxymethyl cellulose hybrid fibers. Carboxymethyl cellulose (CMC) was formed into fibers by wet spinning assisted with PILCl. Co-precipitation test of CMC and PIL-Cl demonstrated that PIL-Cl could precipitate with CMC through strong electrostatic interaction and molar ratio of CMC and PIL-Cl (calculated in repeating units) would affect the formation of precipitation. Secondly, modified PIL-Cl named PIL-Ac was used as an intermediate connecting CMC fiber and graphene to fabricate conductive CMC/PIL/graphene fibers. A series of tests were performed on CMC/PIL/graphene fibers, including Raman spectroscopy, scanning electron microscopy and conductivity test. The results showed that PIL-Cl could help form CMC fiber, and PIL-Ac could functionalize it and make it conductive.


Assuntos
Carboximetilcelulose Sódica/química , Grafite/química , Líquidos Iônicos/química , Polímeros/química , Condutividade Elétrica , Ligação de Hidrogênio , Polímeros/síntese química , Eletricidade Estática
9.
J Pharm Biomed Anal ; 203: 114210, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34171739

RESUMO

An on-line supercritical fluid extraction coupled with supercritical fluid chromatography-quadrupole tandem mass spectrometry method was developed to determine lipids related to inflammation in brain tissues of depressed rats. The analysis of 23 lipids from extraction to separation and detection only took 15 min and required 1 mg of brain tissue powder. The matrix effect of the on-line method for endogenous lipids was systematically investigated, and targeted lipids were quantified by matrix effect corrected calibration curves in this study. The on-line method was comprehensively optimized and evaluated. All calibration curves for lipids showed good linearity (correlation coefficient >0.99). The limits of detection and the limits of quantification were in the range of 0.0261-0.396 pg and 0.0791-1.20 pg. The recoveries and the matrix effect were in the range of 85.3-117.5% and 51.9-176.6%, respectively. The relative standard deviations of precision ranged from 2.7 to 14.2%, with accuracies higher than 87.2%. Compared with liquid-liquid extraction coupled with liquid chromatography-tandem mass spectrometry method, the on-line method obtained higher recovery and sensitivity with significantly reduced analytical time, manual operations, and sample amounts. Finally, this on-line method was applied to analyses of brain tissues of depressed rats. Six pro-inflammatory lipids increased in depressed rats, while six anti-inflammatory lipids decreased. Liquiritin and fluoxetine were presumed to promote a similar synthesis of anti-inflammatory lipids. Based on the results, this on-line method showed great promise in analyzing lipids in complex biological samples.


Assuntos
Cromatografia com Fluido Supercrítico , Animais , Inflamação , Lipídeos , Ratos , Projetos de Pesquisa , Espectrometria de Massas em Tandem
10.
Anal Bioanal Chem ; 413(15): 3975-3986, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33934189

RESUMO

Pseudotargeted analysis combines the advantages of untargeted and targeted lipidomics methods based on chromatography-mass spectrometry (MS). This study proposed a comprehensive pseudotargeted lipidomics method based on three-phase liquid extraction (3PLE) and segment data-dependent acquisition (SDDA). We used a 3PLE method to extract the lipids with extensive coverage from biological matrixes. 3PLE was composed of one aqueous and two organic phases. The upper and middle organic phases enriched neutral lipids and glycerophospholipids, respectively, combined and detected together. Besides, the SDDA strategy improved the detection of co-elution ions in the lipidomics analysis. A total of 554 potential lipids were detected by the developed approach in both positive and negative modes using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Compared with the conventional liquid-liquid extraction (LLE) approaches, including methyl tert-butyl ether (MTBE) and Bligh-Dyer (BD) methods, 3PLE combined with SDDA significantly increased the lipid coverage 87.2% and 89.7%, respectively. Also, the proposed pseudotargeted lipidomics approach exhibited higher sensitivity and better repeatability than the untargeted approach. Finally, we applied the established pseudotargeted method to the plasma lipid profiling from the depressed rats and screened 61 differential variables. The results demonstrated that the pseudotargeted method based on 3PLE and SDDA broadened lipid coverage and improved the detection of co-elution ions with excellent sensitivity and precision, indicating significant potential for the lipidomics analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Depressão/metabolismo , Lipidômica , Extração Líquido-Líquido/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Coelhos , Ratos , Ratos Sprague-Dawley
11.
J Pharm Biomed Anal ; 192: 113646, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33017797

RESUMO

The pseudotargeted lipidomics method integrates the advantages of untargeted andtargeted lipidomics methods as a novel emerging approach. In this study, a green andefficient pseudotargeted lipidomics method based on ultra-high performancesupercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) wasdeveloped. The tandem mass spectra of the analytes were obtained by using UHPSFCwith quadrupole-time of flight MS (Q-TOF MS) in MS E mode and the multiplereaction monitoring (MRM) transitions of the lipidome were defined. Then, thecandidate MRM transitions were verified by UHPSFC with triple quadrupole massspectrometry (QqQ MS) in the scheduled MRM mode. In total, 758 potential lipidscorresponding to 509 and 249 MRM transitions were detected within 8 min in positiveand negative modes, respectively. The established pseudotargeted lipidomics methodwas validated to have excellent analytical characteristics. Compared with thepseudotargeted method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), the UHPSFC-MS/MS-basedpseudotargeted method not only reduced the analytical time by half but also improvedthe sensitivity and resolution for most analytes, especially had better separation forlipid isomers. Besides, the UHPSFC-MS/MS-based pseudotargeted method showedhigher sensitivity and better repeatability for most analytes than the UHPSFC-MS/MS-based untargeted method. The established method was finally applied to investigatingthe lipid profiles of the plasma from the depressed rats and 33 differential variableswere screened, which related to three metabolic pathways. The results indicated thatthe UHPSFC-MS/MS-based pseudotargeted method is reliable and efficient and couldbe used in the lipidomics studies.


Assuntos
Cromatografia com Fluido Supercrítico , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Depressão , Lipidômica , Ratos
12.
J Sep Sci ; 43(11): 2088-2096, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32144949

RESUMO

An enhanced pseudotargeted method using a segment data-dependent acquisition mode based on ultra-high performance liquid chromatography-tandem mass spectrometry was developed. This segment data dependent acquisition-based pseudotargeted method could improve the detection of co-eluted ions and extend the coverage of analytes. A set of 502 multiple reaction monitoring channels were obtained by this segment strategy, which was twice the number created by the traditional data-dependent acquisition mode. Compared with the untargeted method, the pseudotargeted profiling demonstrated higher sensitivity and higher precision. More than 90% of the metabolites detected by the enhanced pseudotargeted method had relative standard deviations less than 15%. The segment data dependent acquisition-based pseudotargeted method was successfully applied to the metabolomics study of the depressed rats with the treatment of liquiritin. Forty-seven differential metabolites were screened and five metabolic pathways were found to be related to depression including retinol metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis, phenylalanine metabolism, terpenoid backbone biosynthesis, and lysine degradation. The segment data dependent acquisition-based pseudotargeted method widened the coverage of metabolites with good sensitivity and precision, which exhibited great potential in the discovery of differential metabolites in metabolomics studies.


Assuntos
Antidepressivos/metabolismo , Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Flavanonas/metabolismo , Flavanonas/uso terapêutico , Glucosídeos/metabolismo , Glucosídeos/uso terapêutico , Metabolômica , Animais , Antidepressivos/urina , Cromatografia Líquida , Depressão/metabolismo , Flavanonas/urina , Glucosídeos/urina , Ratos , Espectrometria de Massas em Tandem
13.
Colloids Surf B Biointerfaces ; 184: 110501, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541891

RESUMO

Supported cross-linked enzyme aggregates were prepared by immobilization of Candida antarctica lipase B onto hydrophobic surface of octyl-modified mesocellular foams (MCFs-C8). Oxidized sodium alginate was used as a substitute for traditional glutaraldehyde. Supported cross-linked enzyme aggregates using oxidized sodium alginate (SA-CLEAs@MCFs-C8) exhibited significantly improved thermal stability and organic solvents tolerance compared to the free lipase, lipase adsorbed onto MCFs-C8 and supported cross-linked enzyme aggregates using glutaraldehyde (G-CLEAs@MCFs-C8). Then immobilized lipases were employed for biodiesel production by transesterification of soybean oil with methanol. In the optimization condition, SA-CLEAs@MCFs-C8 were quite stable and still showed high fatty acid methyl esters (FAME) yield after 5 repeated cycles (from 89% to 78%), whereas MCFs-C8-CALB retained 67% FAME yield (about 72% for G-CLEAs@MCFs-C8).


Assuntos
Alginatos/química , Reagentes de Ligações Cruzadas/química , Proteínas Fúngicas/química , Lipase/química , Estruturas Metalorgânicas/química , Adsorção , Alginatos/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Proteínas Fúngicas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Lipase/metabolismo , Estruturas Metalorgânicas/metabolismo , Estrutura Molecular , Oxirredução , Tamanho da Partícula , Agregados Proteicos , Propriedades de Superfície , Temperatura
14.
J Chromatogr A ; 1606: 460377, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31358297

RESUMO

Traditional Chinese medicines (TCMs) have been widely applied to the prevention and treatment of various illnesses for thousands of years. Sample preparation played a crucial role in the analysis of TCMs because of the complexity of the sample matrixes. In this paper, recent developments and applications of modern sample preparation techniques for the analysis of TCMs were summarized. The sample preparation techniques to pretreat herbal matrixes included ultrasound-assisted extraction, microwave-assisted extraction, pressurized-liquid extraction, supercritical-fluid extraction, synergistic extraction techniques and so on. The sample preparation techniques mainly applied to pretreating biological matrixes such as microdialysis and microfluidic technique were presented. The sample preparation techniques applied to both herbal and biological matrixes were discussed as well, involving solid phase extraction, matrix solid phase dispersion, solid phase microextraction, cloud point extraction, online coupling sample preparation techniques and so on. In addition, the trends for sample preparation techniques of TCMs were proposed.


Assuntos
Métodos Analíticos de Preparação de Amostras , Medicina Tradicional Chinesa , Cromatografia com Fluido Supercrítico , Micro-Ondas , Impressão Molecular , Microextração em Fase Sólida
15.
Int J Biol Macromol ; 130: 342-347, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30825565

RESUMO

Lipase r27RCL from Rhizopus chinensis was immobilized onto octyl-modified mesocellular foams (MCFs-C8) via two-step process of enzyme adsorption and cross-linking. Oxidized gum arabic was used as substitute for harmful glutaraldehyde to improve catalytic performance of immobilized enzyme for catalysis in non-aqueous phase. The parameters like aldehyde concentration, cross-linking time were optimized. Cross-linked enzyme aggregates (CLEAs) of lipase r27RCL prepared in MCFs-C8 by using oxidized gum arabic (GA-CLEAs@MCFs-C8) showed the highest esterification activity (145 µmol min-1 mg-1 protein) compared with lipase adsorbed onto MCFs-C8 (MCFs-C8-r27RCL) (98 µmol min-1 mg-1 protein), CLEAs of lipase in MCFs-C8 by glutaraldehyde (G-CLEAs@MCFs-C8) (88 µmol min-1 mg-1 protein) and immobilized lipase onto octyl/epoxy (1,1, v/v) modified MCFs (MCFs-octyl-epoxy-r27RCL) (35 µmol min-1 mg-1 protein). Moreover, GA-CLEAs@MCFs-C8 exhibited excellent thermal and mechanical stability, and could still maintain 69% of initial activity after 5 time cycles.


Assuntos
Enzimas Imobilizadas/química , Lipase/química , Agregados Proteicos , Rhizopus/enzimologia , Adsorção , Biocatálise , Enzimas Imobilizadas/metabolismo , Esterificação , Goma Arábica/química , Lipase/metabolismo , Fenômenos Mecânicos , Oxirredução , Temperatura
16.
Phys Chem Chem Phys ; 19(17): 10835-10842, 2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28387400

RESUMO

The development of new solvents combining greatly enhanced solubility for sparingly soluble compounds and good kinetic properties is challenging. In this study, we constructed a family of new molecular solvent/ionic liquid (IL) mixtures with amphiphilic, anionic functional long-chain carboxylate ionic liquids (LCC-ILs) as a key component for the solubilization of sparingly soluble compounds, using cholesterol as a model solute. Polarized optical microscopy (POM), wide angle X-ray diffraction (WAXD), Fourier-transform infrared (FTIR) spectra and 1H NMR showed that ordered mesoscopic structures, such as liquid crystals (LCs), were formed when cholesterol was dissolved in the mixtures, presenting a self-assembly induced dissolution mechanism driven by H-bond interaction and van der Waals forces in the mixtures. A synergistic effect between the molecular solvents and LCC-ILs was revealed, which contributed to enhanced solute-solvent self-assembly in dissolution over pure LCC-ILs and thus elevated solubility. Additionally, the effect of IL concentration, solvent type and anionic alkyl-chain length on self-assembly and solubility was investigated. These mixtures showed unparalleled solubilities for cholesterol, while maintaining a low viscosity. The quantitative solubilities (g g-1) of cholesterol were as high as 0.70, 0.84 and 0.82, respectively, at 25 °C in ethyl acetate/[P4444][C15H31COO] (50 wt%), n-heptane/[P4444][C15H31COO] (40 wt%) and ethyl acetate/[P4444][C17H35COO] (50 wt%) mixtures, which were the highest solubilities of cholesterol ever reported, six- to 980-fold higher than traditional molecular solvents and even one- to seven-fold higher compared to pure LCC-ILs. These results demonstrated the considerable potential of molecular solvent/LCC-ILs mixtures as promising solvents for solubilization and advanced separation processes.

17.
Sci Rep ; 7: 41355, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28134341

RESUMO

Chloroplast development is an important subject in botany. In this study, a rice (Oryza sativa) mutant exhibiting impairment in early chloroplast development (seedling leaf albino (sla)) was isolated from a filial generation via hybridization breeding. The sla mutant seedlings have an aberrant form of chloroplasts, which resulted in albinism at the first and second leaves; however, the leaf sheath was green. The mutant gradually turned green after the two-leaf stage, and the third leaf was a normal shade of green. Map-based cloning indicated that the gene OsBT1-3, which belongs to the mitochondrial carrier family (MCF), is responsible for the sla mutant phenotype. OsBT1-3 expression was high in the young leaves, decreased after the two-leaf stage, and was low in the sheath, and these findings are consistent with the recovery of a number of chloroplasts in the third leaf of sla mutant seedlings. The results also showed that OsBT1-3-yellow fluorescent protein (YFP) was targeted to the chloroplast, and a Western blot assay using a peptide-specific antibody indicated that OsBT1-3 localizes to the chloroplast envelope. We also demonstrated that OsBT1-3 functions as a unidirectional transporter of adenine nucleotides. Based on these findings, OsBT1-3 likely acts as a plastid nucleotide uniporter and is essential for chloroplast development in rice leaves at the young seedling stage.


Assuntos
Cloroplastos/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plastídeos/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Bases , Transporte Biológico , Clorofila/metabolismo , Cloroplastos/ultraestrutura , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Metaboloma , Mutação/genética , Oryza/genética , Fenótipo , Fotossíntese/genética , Proteínas de Plantas/genética , Frações Subcelulares/metabolismo
18.
Bioorg Chem ; 68: 214-8, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27561631

RESUMO

A new strategy for the efficient synthesis of C-5 heterocyclyl substituted Coenzyme Q analogues was developed by N-alkylation of bromomethylated quinone 11 with a series of amines 12 under metal-free conditions. In vitro antioxidant activities of these Coenzyme Q analogues were evaluated and compared with commercial antioxidant Coenzyme Q10 by employing DPPH assay. All these N-heterocyclyl substituted Coenzyme Q analogues are found to be exhibiting good antioxidant properties and may be used as potent antioxidants for combating oxidative stress.


Assuntos
Antioxidantes/farmacologia , Compostos Heterocíclicos/farmacologia , Ubiquinona/farmacologia , Antioxidantes/síntese química , Antioxidantes/química , Relação Dose-Resposta a Droga , Compostos Heterocíclicos/química , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Relação Estrutura-Atividade , Ubiquinona/síntese química , Ubiquinona/química
19.
Chem Commun (Camb) ; 51(67): 13170-3, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26165252

RESUMO

Here we report a novel self-assembly induced solubilization strategy with nanostructured ionic liquids as solvents. Highly ordered mesoscopic structures featuring the solute as a key component, such as liquid crystals, were formed via self-assembly in nanostructured long-chain carboxylate ionic liquids, resulting in extremely high solubilities for sparingly soluble drug molecules.


Assuntos
Líquidos Iônicos/química , Nanoestruturas/química , Colesterol/química , Modelos Moleculares , Compostos Orgânicos , Solubilidade
20.
J Pharm Sci ; 104(2): 378-87, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25175154

RESUMO

Adjuvant-containing drug products can be exposed to high levels of interfacial shear during manufacture. This may affect the integrity of the adjuvant, alter its interaction with the drug substance or change the physical characteristics of the drug product. In this study, a solid-liquid interfacial shear device was used to investigate the shear response of aluminum phosphate adjuvant alone and two adjuvant containing vaccine drug products (DP1 and DP2). The relationship between the shear sensitivity of each and its resuspension properties was determined. Changes in the particle dimensions of the bulk adjuvant were minimal at shear strain rates of 10,900 s(-1) . However, at 25,500 s(-1) , the median particle diameter was reduced from 6.2 to 3.5 µm and was marked by the presence of sub-micron fines. A formulation without drug substance and DP2 produced similar shear responses but with less impact on particle diameter. The behavior of DP1 was less predictable. Sheared DP1 was characterized by prolonged sedimentation because of the presence of fine particulates and required in excess of 300 rotations to resuspend after extended storage. The study confirms that the solid-liquid interfacial shear device may be applied to understand product shear sensitivity associated with vaccine manufacturing.


Assuntos
Adjuvantes Imunológicos/química , Compostos de Alumínio/química , Fosfatos/química , Vacinas/química , Antígenos/imunologia , Estabilidade de Medicamentos , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Propriedades de Superfície , Vacinas/imunologia
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