Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
1.
Asian Pac J Allergy Immunol ; 37(1): 36-42, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29888925

RESUMO

BACKGROUND: Lactobacilli show anti-inflammatory effects in the human intestine, and their genomic DNA was identified as one of the anti-inflammatory components. Increased levels of the natural protease inhibitor elafin in the intestine plays an important role in protection against intestinal inflammation. However, there have been no previous reports regarding whether lactobacilli increase elafin levels. OBJECTIVE: This study was performed to investigate whether Lactobacillus plantarum induces elafin secretion from the human epithelial colorectal adenocarcinoma cell line, Caco-2. Moreover, we examined the roles of bacterial genomic DNA and toll-like receptor 9 (TLR9), a specific receptor of bacterial DNA, in this effect. METHODS: Elafin secretion from Caco-2 cells by live and heat-killed L. plantarum was measured. The analysis was also performed using DNase-treated L. plantarum and genomic DNA extracted from L. plantarum. We examined the role of TLR9 in elafin secretion by L. plantarum and its genomic DNA by suppressing TLR9 expression using RNAi in Caco-2 cells. RESULTS: Heat-killed L. plantarum time- and dose-dependently increased elafin secretion, whereas live L. plantarum had no such effect. The elafin secretion by heat-killed L. plantarum was partially abolished by DNase treatment of the bacterium. In addition, L. plantarum genomic DNA also increased elafin secretion. Furthermore, suppression of TLR9 expression partially or completely abolished elafin secretion by heat-killed L. plantarum and its genomic DNA. CONCLUSION: Our results indicated that heat-killed L. plantarum induced genomic DNA-dependent and TLR9-mediated elafin secretion. The anti-inflammatory effects of lactobacilli may be mediated by increases in the levels of elafin in the intestine.


Assuntos
DNA Bacteriano , Elafina/biossíntese , Interações Hospedeiro-Patógeno/genética , Lactobacillus plantarum/fisiologia , Receptor Toll-Like 9/metabolismo , Células CACO-2 , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/metabolismo , Infecções por Bactérias Gram-Positivas/microbiologia , Temperatura Alta , Humanos
2.
J Labelled Comp Radiopharm ; 61(14): 1095-1105, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30375667

RESUMO

GluN2B-containing NMDA receptors (NMDARs) play fundamental roles in learning and memory, although they are also associated with various brain disorders. In this study, we synthesized and evaluated three 11 C-labeled N-benzyl amidine derivatives 2-[11 C]methoxybenzyl) cinnamamidine ([11 C]CBA), N-(2-[11 C]methoxybenzyl)-2-naphthamidine ([11 C]NBA), and N-(2-[11 C]methoxybenzyl)quinoline-3-carboxamidine ([11 C]QBA) as PET radioligands for these receptors. The 11 C-benzyl amidines were synthesized via conventional methylation of corresponding des-methyl precursors with [11 C]CH3 I. In vitro binding characteristics were examined in brain sagittal sections using various GluN2B modulators and off-target ligands. Further, in vivo brain distribution studies were performed in normal mice. The 11 C-labeled benzyl amidines showed high-specific binding to the GluN2B subunit at in vitro. In particular, the quinoline derivative [11 C]QBA had the best binding properties in terms of high-brain localization to GluN2B-rich regions and specificity to the GluN2B subunit. Conversely, these 11 C-radioligands showed the brain distributions were inconsistent with GluN2B expression in biodistribution experiments. The majority of the radiolabeled compounds were identified as metabolized forms of which amido derivatives seemed to be the major species. Although these 11 C-ligands had high-specific binding to the GluN2B subunit, significant improvement in metabolic stability is necessary for successful positron emission tomography (PET) imaging of the GluN2B subunit of NMDARs.


Assuntos
Amidinas/síntese química , Amidinas/metabolismo , Radioisótopos de Carbono , Tomografia por Emissão de Pósitrons/métodos , Receptores de N-Metil-D-Aspartato/metabolismo , Amidinas/química , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Técnicas de Química Sintética , Marcação por Isótopo , Ligantes , Camundongos , Radioquímica
3.
J Med Syst ; 42(6): 114, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29744666

RESUMO

At the University of Miyazaki Hospital (UMH), we have accumulated and semantically structured a vast amount of medical information since the activation of the electronic health record system approximately 10 years ago. With this medical information, we have decided to develop an alert system for aiding in medical treatment. The purpose of this investigation is to not only to integrate an alert framework into the electronic heath record system, but also to formulate a modeling method of this knowledge. A trial alert framework was developed for the staff in various occupational categories at the UMH. Based on findings of subsequent interviews, a more detailed and upgraded alert framework was constructed, resulting in the final model. Based on our current findings, an alert framework was developed with four major items. Based on the analysis of the medical practices from the trial model, it has been concluded that there are four major risk patterns that trigger the alert. Furthermore, the current alert framework contains detailed definitions which are easily substituted into the database, leading to easy implementation of the electronic health records.


Assuntos
Registros Eletrônicos de Saúde/organização & administração , Sistemas de Alerta , Humanos
4.
Bioorg Med Chem ; 24(16): 3727-33, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27325447

RESUMO

Isomeric iodinated derivatives of nimesulide, with an iodine substituent on the phenoxy ring, were prepared with the aim of identifying potential candidate compounds for the development of imaging agents targeting cyclooxygenase-2 (COX-2) in the brain. Both the experimental logP7.4 and pKa values for these iodinated analogs were in the acceptable range for passive brain penetration. The para-iodo-substituted analog was a more potent and selective COX-2 inhibitor than nimesulide, with a potency that was comparable to the reference drug, celecoxib. Iodination at the ortho- or meta-position of the phenoxy ring was associated with a substantial loss of COX-2 inhibitory activity. Transport studies across Caco-2 cell monolayers in the presence and absence of a P-glycoprotein (P-gp) inhibitor, verapamil, indicated that the para-iodo-substituted analog was not a P-gp transport substrate; this feature is a prerequisite for potential in vivo brain imaging compounds. The para-iodo-substituted analog of nimesulide appears to be an attractive candidate for the development of radioiodine-labeled tracers for in vivo brain imaging of COX-2 levels.


Assuntos
Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Animais , Encéfalo/metabolismo , Células CACO-2 , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/farmacocinética , Humanos , Isomerismo , Camundongos , Camundongos Endogâmicos BALB C , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfonamidas/síntese química , Sulfonamidas/farmacocinética
5.
Bioorg Med Chem ; 23(21): 6807-14, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26455657

RESUMO

Nimesulide analogs bearing a methoxy substituent either at the ortho-, meta- or para-position on the phenyl ring, were designed, synthesized, and evaluated for potential as radioligands for brain cyclooxygenase-2 (COX-2) imaging. The synthesis of nimesulide and regioisomeric methoxy analogs was based on the copper-mediated arylation of phenolic derivatives for the construction of diaryl ethers. These isomeric methoxy analogs displayed lipophilicity similar to that of nimesulide itself, as evidenced by their HPLC logP7.4 values. In vitro inhibition studies using a colorimetric COX (ovine) inhibitor-screening assay demonstrated that the para-methoxy substituted analog retains the inhibition ability and selectivity observed for parent nimesulide toward COX-2 enzyme, whereas the meta- and ortho-methoxy substituents detrimentally affected COX-2-inhibition activity, which was further supported by molecular docking studies. Bidirectional transport cellular studies using Caco-2 cell culture model in the presence of the P-glycoprotein (P-gp) inhibitor, verapamil, showed that P-gp did not have a significant effect on the efflux of the para-methoxy substituted analog. Further investigations using the radiolabeled form of the para-methoxy substituted analog is warranted for in vivo characterization.


Assuntos
Meios de Contraste/síntese química , Inibidores de Ciclo-Oxigenase 2/síntese química , Ciclo-Oxigenase 2/metabolismo , Sulfonamidas/química , Encéfalo/enzimologia , Células CACO-2 , Domínio Catalítico , Meios de Contraste/química , Meios de Contraste/metabolismo , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/metabolismo , Humanos , Isomerismo , Conformação Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Sulfonamidas/síntese química , Sulfonamidas/metabolismo
6.
Bioorg Med Chem ; 22(21): 6039-46, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25281270

RESUMO

NAD(P)H: quinone oxidoreductase 1 (NQO1) is an obligate two-electron reductase and is highly expressed in many human solid cancers. Because NQO1 can be induced immediately after exposure to ionizing radiation, we aimed to develop an NQO1-targeted radiolabeled agent to establish a novel internal radiation therapy that amplifies the therapeutic effects when combined with external radiation therapy. We designed three NQO1-targeted radioiodinated compounds including two ether linkage compounds ([(125)I]1 and [(125)I]2) and a sulfide linkage compound ([(125)I]3) based on the selective binding of indolequinone analogs to the active site of NQO1 by the stacking effect. These compounds were successfully prepared using an oxidative iododestannylation reaction with high radiochemical yields and purity. In NQO1-expressing tumor cells, [(125)I]1 and [(125)I]2 were readily metabolized to p-[(125)I]iodophenol or m-[(125)I]iodophenol and [(125)I]I(-), whereas over 85% of the initial radioactivity of [(125)I]3 was observed as an intact form at 1h after incubation. The cellular uptake of [(125)I]3 was significantly higher than those of [(125)I]1 and [(125)I]2. The uptake of [(125)I]3 was specific and was dependent on the expression of NQO1. These data suggest that the novel NQO1-targeted radioiodinated compound [(125)I]3 could be used as a novel internal radiation agent for the treatment of cancer.


Assuntos
Indolquinonas/química , NAD(P)H Desidrogenase (Quinona)/metabolismo , Neoplasias/radioterapia , Compostos Radiofarmacêuticos/química , Linhagem Celular Tumoral , Halogenação , Humanos , Indolquinonas/síntese química , Indolquinonas/metabolismo , Indolquinonas/farmacocinética , Radioisótopos do Iodo/química , Radioisótopos do Iodo/metabolismo , Radioisótopos do Iodo/farmacocinética , Neoplasias/metabolismo , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Radioterapia/métodos
7.
Biol Pharm Bull ; 36(4): 602-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23546294

RESUMO

On the basis of the findings obtained by X-ray crystallography of Ga-DOTA chelates and the drug design concept of bifunctional radiopharmaceuticals, we previously designed and synthesized a radiogallium-labeled DOTA chelate containing two metronidazole moieties, (67)Ga-DOTA-MN2, for hypoxic tumor imaging. As expected, (67)Ga-DOTA-MN2 exhibited high in vivo stability, although two carboxyl groups in the DOTA skeleton were conjugated with metronidazole moieties. In this study, we evaluated (67/68)Ga-DOTA-MN2 as a nuclear imaging agent for hypoxic tumors. (67)Ga-labeling of DOTA-MN2 with (67)GaCl(3) was achieved with high radiochemical yield (>85%) by 1-min of microwave irradiation (50 W). The pharmacokinetics of (67)Ga-DOTA-MN2 were examined in FM3A tumor-bearing mice, and compared with those of (67)Ga-DOTA-MN1 containing one metronidazole unit and (67)Ga-DOTA. Upon administration, (67)Ga-DOTA-MN2 exhibited higher accumulation in the implanted tumors than (67)Ga-DOTA. Tumor-to-blood ratios of (67)Ga-DOTA-MN2 were about two-fold higher than those of (67)Ga-DOTA-MN1. Autoradiographic analysis showed the heterogeneous localization of (67)Ga-DOTA-MN2 in the tumors, which corresponds to hypoxic regions suggested by well-established hypoxia marker drug, pimonidazole. Furthermore, in positron emission tomography (PET) study, the tumors of mice administered (68)Ga-labeled DOTA-MN2 were clearly imaged by small-animal PET at 1 h after administration. This study demonstrates the potential usefulness of (67/68)Ga-DOTA-MN2 as a nuclear imaging agent for hypoxic tumors and suggests that two functional moieties, such as metronidazole, can be conjugated to radiogallium-DOTA chelate without reducing the complex stability. The present findings provide useful information about the chemical design of radiogallium-labeled radiopharmaceuticals for PET and single photon emission computed tomography (SPECT) studies.


Assuntos
Meios de Contraste/farmacocinética , Radioisótopos de Gálio/farmacocinética , Compostos Heterocíclicos com 1 Anel/farmacocinética , Neoplasias Mamárias Animais/diagnóstico por imagem , Metronidazol/farmacocinética , Animais , Linhagem Celular Tumoral , Meios de Contraste/química , Feminino , Radioisótopos de Gálio/sangue , Radioisótopos de Gálio/química , Compostos Heterocíclicos com 1 Anel/sangue , Compostos Heterocíclicos com 1 Anel/química , Hipóxia , Metronidazol/sangue , Metronidazol/química , Camundongos , Camundongos Endogâmicos C3H , Tomografia por Emissão de Pósitrons , Distribuição Tecidual
8.
Chem Pharm Bull (Tokyo) ; 60(2): 235-40, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22293483

RESUMO

As a part of our efforts to develop potential imaging agents for ascorbate bioactivity, 5-O-(4-[(125)I]iodobenzyl)-L-ascorbic acid ([(125)I]1) was prepared through a two-step sequence which involved radioiodo-destannylation of a protected tributylstannyl precursor 6, followed by hydrolysis in acidic methanol of the protecting groups in 61% overall radiochemical yield, with a radiochemical purity of over 98% and a specific activity of more than 15.4 GBq/µmol. Tissue distribution of [(125)I]1 in tumor-bearing mice showed signs of distribution profiles similar to the reported results for 6-deoxy-6-[(18)F]fluoro-L-ascorbic (6-(18)FAsA) acid and 6-deoxy-6-[(131)I]iodo-L-ascorbic acid (6-(131)IAsA) but with notable differences in the adrenal glands, in which considerably lower uptake of radioactivity and rapid clearance with time were observed. Pretreatment of mice with a known inhibitor of ascorbate transport, sulfinpyrazone, did not produce any significant change in the adrenal uptake of radioactivity after injection of [(125)I]1 compared to the control, suggesting that uptake in the adrenal glands is independent of the sodium-dependent vitamin C transporter 2 transport mechanism. Introduction of a bulky substituent at C-5 on AsA, such as an iodobenzyloxy group, may not be suitable for the design of analogs that may still be able to maintain characteristic distribution properties in vivo seen with AsA itself.


Assuntos
Ácido Ascórbico/análogos & derivados , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Animais , Ácido Ascórbico/química , Ácido Ascórbico/farmacocinética , Cromatografia Líquida de Alta Pressão , Fibrossarcoma/diagnóstico por imagem , Radioisótopos do Iodo , Camundongos , Estrutura Molecular , Cintilografia
9.
FEBS Open Bio ; 12(8): 1534-1541, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35638574

RESUMO

Cry toxins from Bacillus thuringiensis (Bt) have been extensively applied in agriculture to substitute the use of chemical insecticides. We have previously reported the use of a coexpression system in which late embryogenesis abundant (LEA) peptides under the control of the lac promoter increase the expression of insecticidal proteins in Bt. The use of lactose to induce the expression of LEA peptides may be a desirable alternative to isopropyl ß-D-thiogalactopyranoside, the most frequently used inducer for recombinant protein expression. In this study we investigated the use of lactose as an inducer for optimal protein expression. We observed enhanced insecticidal Cry protein expression by applying a simple technique based on intermittent induction, and then optimized concentration and the point of induction time from the 11th h to the 15th h. Our data suggest that intermittent induction of lactose might be a new technique for the enhancement of bacterial protein expression.


Assuntos
Bacillus thuringiensis , Inseticidas , Bacillus thuringiensis/metabolismo , Desenvolvimento Embrionário , Inseticidas/metabolismo , Inseticidas/farmacologia , Lactose/metabolismo , Lactose/farmacologia , Peptídeos/metabolismo
10.
ACS Appl Mater Interfaces ; 14(2): 3418-3426, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34985245

RESUMO

A superconducting joint architecture to join unreacted carbon-doped multifilament magnesium diboride (MgB2) wires with the functionality to screen external magnetic fields for magnetic resonance imaging (MRI) magnet applications is proposed. The intrinsic diamagnetic property of a superconducting MgB2 bulk was exploited to produce a magnetic field screening effect around the current transfer path within the joint. Unprecedentedly, the joint fabricated using this novel architecture was able to screen magnetic fields up to 1.5 T at 20 K and up to 2 T at 15 K and thereby almost nullified the effect of the applied magnetic field by maintaining a constant critical current (Ic). The joint showed an Ic of 30.8 A in 1.5 T at 20 K and an ultralow resistance of about 3.32 × 10-14 Ω at 20 K in a self-field. The magnetic field screening effect shown by the MgB2 joint is expected to be extremely valuable for MRI magnet applications, where the Ic of the joints is lower than the Ic of the connected MgB2 wires in a given magnetic field and temperature.

11.
Chem Pharm Bull (Tokyo) ; 59(8): 938-46, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21804236

RESUMO

There is great potential in the use of positron emission tomography (PET) and suitable radiotracers for the study of cyclooxygenase type 2 (COX-2) enzyme in living subjects. In the present study, we prepared and evaluated five ¹¹C-labeled ester and amide analogs derived from indomethacin as potential PET imaging agents for the in vivo visualization of the brain COX-2 enzyme. Five ¹¹C-labeled COX-2 inhibitors, with different lipophilicities and moderate COX-2 inhibitory activity, were prepared by treatment of the corresponding O-desmethyl precursors with [¹¹C]methyl triflate and purified by HPLC (radiochemical yields of 55-71%, radiochemical purity of >93%, and the specific activities of 22-331 GBq/µmol). In mice, radioactivity in the brain for all radiotracers was low, with very low brain-to-blood ratios. A clear inverse relationship was observed between brain uptake at 1 min postinjection and the lipophilicity (experimental log P7.4) of the studied ¹¹C-radiotracers. Pretreatment of mice with cyclosporine A to block P-glycoproteins caused a significant increase in brain uptake of radioactivity following injection of the ¹¹C-radiotracer compared to control. HPLC analysis showed that each radiotracer was rapidly metabolized, and a few metabolites, which were more polar than the original radiotracers, were found in both plasma and brain. No specific binding of the tracers towards the COX-2 enzyme in the brain was clearly revealed by in vivo blocking study. Further structural refinement of the tracer agent is necessary for better enhancement of brain uptake and for sufficient metabolic stability.


Assuntos
Amidas/química , Encéfalo/diagnóstico por imagem , Ciclo-Oxigenase 2/análise , Inibidores de Ciclo-Oxigenase/química , Indometacina/análogos & derivados , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Amidas/metabolismo , Amidas/farmacocinética , Animais , Encéfalo/metabolismo , Radioisótopos de Carbono/química , Radioisótopos de Carbono/metabolismo , Radioisótopos de Carbono/farmacocinética , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/metabolismo , Inibidores de Ciclo-Oxigenase/farmacocinética , Ésteres/química , Indometacina/metabolismo , Indometacina/farmacocinética , Marcação por Isótopo , Masculino , Camundongos , Ligação Proteica , Compostos Radiofarmacêuticos/metabolismo , Compostos Radiofarmacêuticos/farmacocinética
12.
J Microbiol Methods ; 188: 106207, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33766605

RESUMO

Bacillus thuringiensis (Bt) is a ubiquitous, gram positive, spore-forming bacterium that synthesizes parasporal crystalline inclusions containing crystal protein, some of which are toxic against a wide range of insect orders like caterpillars, beetles, and flies, including mosquitoes. Regarding the biological control of insects, Bt is the mostly used microorganism worldwide and also alternatives to chemical insecticides for environmental conservation. Some strains of Bt are showing a promising activity against a wide variety of mosquito like Aedes, Culex, and Anopheles and so on with extremely damages in the larval midgut and ultimate death. Here, we introduced a late embryogenesis abundant (LEA) peptide co-expression system based on the expression vector pHT01 with a strong σA-dependent promoter to enhance the expression of insecticidal crystal proteins in native Bt. Two types of LEA peptide (LEA-II and LEA-K) were designed based on the sequence of group-3 LEA protein, which consists of a repetitive sequence of 11 amino acids. The LEA-II mediated co-expression system enhanced the production of crystal protein 3-fold after 12 h of induction of the peptide with 0.5 mM IPTG. Enhanced expression of crystal protein was confirmed by bioassay using 4th instar Aedes albopictus larvae. This unique approach has great potential to produce bio-pesticides by enhanced crystal protein expression not only for mosquitoes but also for other insects.


Assuntos
Toxinas de Bacillus thuringiensis/farmacologia , Bacillus thuringiensis/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Inseticidas/farmacologia , Peptídeos/metabolismo , Animais , Anopheles , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endotoxinas/química , Endotoxinas/genética , Proteínas Hemolisinas/genética , Inseticidas/metabolismo , Larva/efeitos dos fármacos , Peptídeos/genética , Proteômica
13.
ACS Appl Mater Interfaces ; 13(2): 3349-3357, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33400882

RESUMO

A superconducting joint of unreacted monofilament internal magnesium diffusion-processed magnesium diboride (MgB2) wires was fabricated by exploiting the phenomenon of magnesium diffusion into the boron layer inside the superconducting joint. Unprecedentedly, the joint was able to carry an almost identical transport current compared to the bare wire in a 2-7 T magnetic field at 20 K. The joint also exhibited very low joint resistance of 2.01 × 10-13 Ω in self-field at 20 K. Among commercially available superconductors, this work is the first to successfully realize a superconducting joint that is capable of transferring current from one conductor to another without any notable degradation under strong magnetic fields. This work demonstrates great potential to apply MgB2 in a range of practical applications, where superconducting joints are essential.

14.
Chem Pharm Bull (Tokyo) ; 58(8): 1020-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20686253

RESUMO

3-Methyl-1-phenyl-2-pyrazolin-5-one (edaravone, 1), known as a potent free radical scavenger, has been developed as a medical drug for the treatment of acute cerebral infarction. With the aim of developing radiotracers for imaging free radicals in vivo, 1-(3'-[(125)I]iodophenyl)-3-methy-2-pyrazolin-5-one ((125)I-2) was synthesized by two methods, via isotopic exchange and interhalogen exchange under solvent-free conditions, in which iodo- and bromo-derivatives were used as labeling precursors, respectively. After HPLC purification, (125)I-2 was obtained in modest isolated radiochemical yields (ca. 20%) with high radiochemical purities by both methods. The former gave specific activities of 0.2-0.6 kBq/micromol, whereas the latter approach achieved specific activities of more than 0.14 GBq/micromol. On attempting to prepare an injectable formulation for (125)I-2 with high specific activity, its radiochemical purities dropped to about 60-70%. Unlabeled analog 2 was found to have lipophilic and antioxidant properties similar to edaravone. Intravenous injection of (125)I-2 with low specific radioactivity into normal mice showed signs of distribution profiles similar to reported results for (14)C-labeled edaravone in normal rats.


Assuntos
Antioxidantes/síntese química , Antioxidantes/farmacocinética , Antipirina/análogos & derivados , Pirazolonas/química , Pirazolonas/farmacocinética , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Antipirina/administração & dosagem , Antipirina/síntese química , Antipirina/química , Antipirina/farmacocinética , Estabilidade de Medicamentos , Edaravone , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Pirazolonas/administração & dosagem , Pirazolonas/síntese química , Solubilidade , Distribuição Tecidual
15.
Bioorg Med Chem ; 17(13): 4285-9, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19481944

RESUMO

From the X-ray crystal structures of Ga-DOTA chelates, we were able to deduce that two free carboxylate groups of the radiogallium-DOTA complex may be utilized for coupling to functional moieties that recognize molecular targets for in vivo imaging without reducing the radiogallium-complex stability. Thus, we designed 2,2'-[4,10-bis(2-{[2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl]amino}-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,7-diyl]diacetic acid (DOTA-MN2) (7), employing a metronidazole moiety as the recognition site of hypoxic lesions, based on the drug design concept of bifunctional radiopharmaceuticals. Coupling of DOTA-bis(tert-butyl)ester 5 with 1-(2-aminoethyl)-2-methyl-5-nitroimidazole dihydrochloride, followed by deprotection, afforded the required 7 (DOTA-MN2). (67)Ga-labeling was carried out by reaction of DOTA-MN2 with (67)Ga-citrate. When (67)Ga-DOTA-MN2 was incubated in phosphate-buffered saline or mouse plasma, no measurable decomposition occurred over a 24-h period. In biodistribution experiments in NFSa tumor-bearing mice, (67)Ga-DOTA-MN2 displayed not only a significant tumor uptake, but also rapid blood clearance and low accumulations in nontarget tissues, resulting in high target-to-nontarget ratios of radioactivity. These results indicate the potential benefits of the drug design of (67)Ga-DOTA-MN2. The present findings provide helpful information for the development of radiogallium-labeled radiopharmaceuticals for SPECT and PET studies.


Assuntos
Fibrossarcoma/diagnóstico por imagem , Compostos Heterocíclicos com 1 Anel/química , Compostos Heterocíclicos com 1 Anel/farmacocinética , Imidazóis/química , Imidazóis/farmacocinética , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Animais , Desenho de Fármacos , Estabilidade de Medicamentos , Feminino , Radioisótopos de Gálio/química , Radioisótopos de Gálio/farmacocinética , Compostos Heterocíclicos com 1 Anel/síntese química , Imidazóis/síntese química , Metronidazol/química , Metronidazol/farmacocinética , Camundongos , Camundongos Endogâmicos C3H , Cintilografia , Compostos Radiofarmacêuticos/síntese química
16.
Bioorg Med Chem ; 17(15): 5665-75, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19586774

RESUMO

In this study, we synthesized and evaluated several amino 4-hydroxy-2(1H)-quinolone (4HQ) derivatives as new PET radioligand candidates for the glycine site of the NMDA receptors. Among these ligands, we discovered that 7-chloro-4-hydroxy-3-{3-(4-methylaminobenzyl) phenyl}-2-(1H)-quinolone (12) and 5-ethyl-7-chloro-4-hydroxy-3-(3-methylaminophenyl)-2(1H)-quinolone (32) have high affinity for the glycine site (K(i) values; 11.7 nM for 12 and 11.8 nM for 32). In vitro autoradiography experiments indicated that [(11)C]12 and [(11)C]32 showed high specific binding in the brain slices, which were strongly inhibited by both glycine agonists and antagonists. In vivo brain uptake of these (11)C-labeled 4HQs were examined in normal mice. Cerebellum to blood ratio of accumulation, of both [(11)C]12 and [(11)C]32 at 30 min were 0.058, which were slightly higher than those of cerebrum to blood ratio (0.043 and 0.042, respectively). These results indicated that [(11)C]12 and [(11)C]32 have poor blood brain barrier permeability. Although the plasma protein-binding ratio of [(11)C]32 was much lower than methoxy analogs (71% vs 94-98%, respectively), [(11)C]32 still binds with plasma protein strongly. It is conjectured that still acidic moiety and high affinity with plasma protein of [(11)C]32 may prevent in vivo brain uptake. In conclusion, [(11)C]12 and [(11)C]32 are unsuitable for imaging cerebral NMDA receptors.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Quinolonas/química , Quinolonas/metabolismo , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/metabolismo , Receptores de N-Metil-D-Aspartato/análise , Animais , Autorradiografia , Sítios de Ligação , Encéfalo/metabolismo , Glicina/metabolismo , Camundongos , Estrutura Molecular , Ligação Proteica , Quinolonas/sangue , Quinolonas/farmacocinética , Radioquímica , Compostos Radiofarmacêuticos/sangue , Compostos Radiofarmacêuticos/farmacocinética , Receptores de N-Metil-D-Aspartato/metabolismo , Relação Estrutura-Atividade
17.
Biol Pharm Bull ; 32(11): 1906-11, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19881306

RESUMO

Normal female rat distribution studies showed high and specific uptake of 6-deoxy-6-[(131)I]iodo-L-ascorbic acid (6-(131)IAsA) into the adrenal glands, known to highly express the ascorbate sodium-dependent vitamin C transporter-2 (SVCT-2), and the adrenal gland was clearly visualized by whole-body autoradiography. Preinjection of sulfinpyrazone, a known blocker of ascorbate transport, with 6-(131)IAsA resulted in decreased uptake of radioactivity in rat adrenal glands compared to the control group, seemingly illustrating the participation of the SVCT transporter (probably the SVCT-2 subtype) in the uptake process in vivo. 4-Aminopyrazolo[3,4-d]pyrimidine-induced hypolipidemic rats showed a 1.7-fold increase in adrenal uptake of radioactivity at 30 min postinjection of 6-(131)IAsA, compared to the control, with increased adrenal-to-liver and adrenal-to-kidney ratios. To further characterize 6-(131)IAsA for its tumor uptake properties, biodistribution studies were also performed using male nude mice implanted with either Y-1 adrenocortical tumor cells or adrenal medulla-derived PC12 cells. None of these tumors exhibited relevant uptake of 6-(131)IAsA while normal adrenal glands showed high uptake of radioactivity, suggesting that these tumors in this model have only a poor transport capacity for this agent. The present study demonstrates that the use of radioiodinated 6-IAsA may help to obtain information about functional alterations in diseased adrenal glands, but it does not exhibit desirable properties as a tumor-seeking agent for ascorbic acid bioactivity.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Radioisótopos do Iodo/farmacocinética , Lipídeos/sangue , Neoplasias Experimentais/metabolismo , Animais , Ácido Ascórbico/farmacocinética , Autorradiografia , Cromatografia Líquida de Alta Pressão , Feminino , Masculino , Camundongos , Camundongos Nus , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
18.
J Toxicol Sci ; 44(7): 459-469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31270302

RESUMO

Phenobarbital (PB) and Di (2-ethylhexyl) phthalate (DEHP), an anti-epileptic drug and a plasticizer used in flexible polyvinylchloride formulations, respectively, are well-known typical hepatotoxicants. This study investigated the effects of PB (100 mg/kg/day) or DEHP (500 mg/kg/day) on the endocrine system in intact juvenile/peripubertal male rats exposed for 31 days beginning on postnatal day 23. Slight hormone level changes, histopathological changes in thyroid gland or induction of UDP-glucuronosyltransferase in liver were observed in both the PB and DEHP groups. One of the assumed mechanisms inducing thyroid effects is predictable to be secondary changes based on the enhancement in thyroid hormone metabolism via the induction of hepatic microsomal enzymes. No reproductive system-related changes in organ weights, histopathology, and sexual maturation were observed in both groups. Lower testosterone level was observed in the PB group. CYP2B and CYP3A, which are involved in testosterone metabolism, were induced in liver of the PB group. There was no change of 17ß-hydroxysteroid dehydrogenase activity in testis of both groups. Lower testosterone level in the PB-treated male rats was attributed to an indirect, hepatotoxicity-associated effect on the reproductive system and not to direct effects on testis such as the antiandrogenic activity and the inhibition of steroidogenesis. These results did not indicate that PB or DEHP exposure affects the endocrine system directly.


Assuntos
Anticonvulsivantes/toxicidade , Dietilexilftalato/toxicidade , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/patologia , Fenobarbital/toxicidade , Plastificantes/toxicidade , Animais , Animais Recém-Nascidos , Anticonvulsivantes/administração & dosagem , Sistema Enzimático do Citocromo P-450/metabolismo , Glucuronosiltransferase/metabolismo , Fígado/enzimologia , Masculino , Fenobarbital/administração & dosagem , Ratos Sprague-Dawley , Testosterona/metabolismo , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Fatores de Tempo
19.
Sci Rep ; 9(1): 14287, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582758

RESUMO

Superconducting joints are essential for persistent-mode operation in a superconducting magnet system to produce an ultra-stable magnetic field. Herein, we report rationally designed niobium-titanium (Nb-Ti) superconducting joints and their evaluation results in detail. For practical applications, superconducting joints were fabricated by using a solder matrix replacement method with two types of lead-bismuth (Pb-Bi) solder, including Pb42Bi58 as a new composition. All the joints attained a critical current of >200 A below 1.43 T at 4.2 K. Our optimized superconducting joining method was tested in a closed-loop coil, obtaining a total circuit resistance of 3.25 × 10-14 Ω at 4.2 K in self-field. Finally, persistent-mode operation was demonstrated in an Nb-Ti solenoid coil with a persistent-current switch. This work will pave the way to developing high-performance Nb-Ti superconducting joints for practical applications.

20.
FEMS Microbiol Lett ; 288(2): 171-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19054081

RESUMO

LAMP is a novel method that amplifies DNA with high specificity and rapidity under isothermal conditions. In this study, using the LAMP method, a diagnostic protocol was developed for the detection of Vibrio nigripulchritudo in shrimps. Vibrio nigripulchritudo is associated with distinct shrimp diseases (vibriosis) and is considered one of the threatening pathogens in shrimp industry. After initial cloning and sequencing of the intergenic spacer region (ITS) between 16S and 23S rRNA genes of V. nigripulchritudo, a set of four primers - two inner and two outer - were designed for use in the LAMP reaction. Reaction time and temperature were optimized for 60 min at 63 degrees C, respectively. The detection limit of V. nigripulchritudo by LAMP was 10(2) CFU mL(-1) but PCR could detect up to 10(3) CFU mL(-1). The LAMP method could detect the presence of V. nigripulchritudo from heart, lymphoid organ, and muscle of experimentally infected shrimps with V. nigripulchritudo. This study established a highly sensitive and a rapid diagnostic procedure for detection of V. nigripulchritudo in shrimps. The method developed in this study could be very useful for routine shrimp disease diagnostics.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Penaeidae/microbiologia , Vibrio/isolamento & purificação , Animais , Primers do DNA , DNA Bacteriano/análise , DNA Espaçador Ribossômico/análise , Genes de RNAr , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA , Vibrio/classificação , Vibrio/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA