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1.
J Health Commun ; 28(4): 218-230, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36961052

RESUMO

Staying at home substantially reduces the spread of COVID-19. Moreover, understanding why people stayed at home by addressing its social cognitive determinants can help create more effective communication to change behaviors. This study analyzed this outcome through an extended model of the theory of planned behavior based on risk perception and personal norms in four countries: the United States, Japan, Brazil, and Taiwan. 1,196 individuals participated in this study through a questionnaire focused on planned behavior, moral norms, and risk perception. The data showed that intention and perceived behavioral control influenced behavior significantly, while attitude, injunctive norms, perceived behavioral control, personal norms, and risk perception influenced intention. With multigroup analysis and ANOVA, we verified significant differences in the estimates and mean scores across cultures, revealing the need for scholars to analyze outcomes based on geography and local political culture. Given that health communications played a key role in managing the pandemic, this study clarifies the social cognitive determinants of staying at home and how the local political culture can impact their influence. Thus, we provide an evidence-based prescription for focused communications.


Assuntos
COVID-19 , Comunicação em Saúde , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias , Intenção , Atitude
2.
Opt Express ; 30(3): 3538-3552, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209609

RESUMO

We developed model equations of light scattering properties and a characteristic time of light propagation for polydisperse colloidal suspensions at different volume fractions. By the model equations, we examined numerical results using the first-order (dependent) scattering theory (FST) and radiative transfer theory in 600-980 nm wavelength. The model equations efficiently treat the interference of electric fields scattered from colloidal particles by a single effective coefficient, providing fast computation. Meanwhile, the FST provides accurate but complicated treatment. We found the interference effects on the scattering properties and characteristic time depend linearly on wavelength. Dimensionless analysis showed a simple mechanism of the interference effects, independently of wavelength and source-detector distance.

3.
Bioorg Med Chem ; 46: 116343, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34450571

RESUMO

A series of tricyclic ß-lactams were synthesized and evaluated for in vitro antibacterial activities against carbapenem-resistant Enterobacterales (CREs). Starting from a reported tricyclic ß-lactam that combined the cephalosporin skeleton having a γ-lactone ring with a carboxylic acid group, which was reported as a unique partial structure of Lactivicin, we identified the compound which shows potent antibacterial activities against all tested CREs by introducing sulfoxide. In addition, the sulfoxide-introduced tricyclic ß-lactam also shows a strong therapeutic efficacy in the neutropenic mouse lung infection model. These results indicate that the tricyclic ß-lactam skeleton will show sufficient therapeutic performance in clinical use and therefore can serve as a scaffold in the search for new antibacterial agents against CREs.


Assuntos
Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , beta-Lactamas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Carbapenêmicos/síntese química , Carbapenêmicos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , beta-Lactamas/síntese química , beta-Lactamas/química
4.
J Org Chem ; 85(15): 9650-9660, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32638592

RESUMO

Approval of avibactam by the FDA has led to the recognition of 1,6-diazabicyclo[3.2.1]octane (DBO) derivatives as attractive compounds for ß-lactamase inhibition. We achieved a concise and collective synthesis of 2-thio-substituted DBO derivatives. The synthesis involves diastereoselective photo-induced Barton decarboxylative thiolation, which can be applied to large-scale synthesis. The DBO analogues exhibited strong inhibitory activities against serine ß-lactamases and acceptable solution stabilities for clinical development.


Assuntos
Octanos , Inibidores de beta-Lactamases , Antibacterianos , Compostos Azabicíclicos/farmacologia , Testes de Sensibilidade Microbiana , Octanos/farmacologia , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases
5.
J Pharmacol Exp Ther ; 348(3): 372-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24338505

RESUMO

AS1069562 [(R)-2-[(1H-inden-7-yloxy)methyl]morpholine monobenzenesulfonate] is the (+)-isomer of indeloxazine, which had been used clinically for the treatment of cerebrovascular diseases with multiple pharmacological actions, including serotonin (5-HT) and norepinephrine (NE) reuptake inhibition. Here we investigated the analgesic effects of AS1069562 in a rat model of chronic constriction injury (CCI)-induced neuropathic pain and the spinal monoamine turnover. These effects were compared with those of the antidepressants duloxetine and amitriptyline. AS1069562 significantly elevated extracellular 5-HT and NE levels in the rat spinal dorsal horn, although its 5-HT and NE reuptake inhibition was much weaker than that of duloxetine in vitro. In addition, AS1069562 increased the ratio of the contents of both 5-HT and NE to their metabolites in rat spinal cord, whereas duloxetine slightly increased only the ratio of the content of 5-HT to its metabolite. In CCI rats, AS1069562 and duloxetine significantly ameliorated mechanical allodynia, whereas amitriptyline did not. AS1069562 and amitriptyline significantly ameliorated thermal hyperalgesia, and duloxetine tended to ameliorate it. Furthermore, AS1069562, duloxetine, and amitriptyline significantly improved spontaneous pain-associated behavior. In a gastric emptying study, AS1069562 affected gastric emptying at the same dose that exerted analgesia in CCI rats. On the other hand, duloxetine and amitriptyline significantly reduced gastric emptying at lower doses than those that exerted analgesic effects. These results indicate that AS1069562 broadly improved various types of neuropathic pain-related behavior in CCI rats with unique characteristics in spinal monoamine turnover, suggesting that AS1069562 may have potential as a treatment option for patients with neuropathic pain, with a different profile from currently available antidepressants.


Assuntos
Analgésicos/uso terapêutico , Monoaminas Biogênicas/metabolismo , Morfolinas/uso terapêutico , Neuralgia/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Amitriptilina/farmacologia , Analgésicos/farmacocinética , Analgésicos/farmacologia , Animais , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Cloridrato de Duloxetina , Esvaziamento Gástrico/efeitos dos fármacos , Células HEK293 , Humanos , Masculino , Morfolinas/farmacocinética , Morfolinas/farmacologia , Atividade Motora/efeitos dos fármacos , Neuralgia/fisiopatologia , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Medula Espinal/metabolismo , Estereoisomerismo , Tiofenos/farmacocinética , Tiofenos/farmacologia
6.
J Anesth ; 27(6): 939-41, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23760511

RESUMO

Voltage-dependent sodium channels (VDSCs) are crucial for pain generation. Here, to develop a new behavioral index of pain induced by spinal VDSC activation, we examined whether intrathecal veratridine injection produced nociceptive behavior. Intrathecal injection of the VDSC opener veratridine in mice dose-dependently induced nociceptive responses, with response times subsequently reduced by administration of morphine or pregabalin. Systemic administration of lidocaine and mexiletine, but not amitriptyline, also decreased this response time. Taken together, these results demonstrated that response time of nociceptive behavior induced by intrathecal veratridine injection is a quantitative index of pain triggered by spinal VDSC activation.


Assuntos
Dor Nociceptiva/induzido quimicamente , Manejo da Dor/métodos , Medição da Dor/métodos , Coluna Vertebral/efeitos dos fármacos , Agonistas do Canal de Sódio Disparado por Voltagem/farmacologia , Canais de Sódio Disparados por Voltagem/metabolismo , Amitriptilina/farmacologia , Animais , Injeções Espinhais , Lidocaína/farmacologia , Masculino , Mexiletina/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Morfina/farmacologia , Dor Nociceptiva/tratamento farmacológico , Pregabalina , Coluna Vertebral/metabolismo , Ácido gama-Aminobutírico/análogos & derivados , Ácido gama-Aminobutírico/farmacologia
7.
Soc Neurosci ; 18(5): 282-291, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37997763

RESUMO

Public facilities that have NIMBY (not in my backyard) structure involve both a social dilemma, in which individuals' decisions to prevent the worst outcomes for themselves undermine the public interest, and a moral dilemma focused on the majority versus the minority. This study examined the cognitive-neural processes in judging whether to prioritize the site residents or the citizenry as a whole within the context of NIMBY. Our ROIs were the right angular gyrus being related to concern about the worst possible outcomes for others and oneself, the amygdala associating with emotional aversion to prioritizing the majority, and the vmPFC, which integrates the aversion into "all things considered" judgments. As a result of comparing ingroup conditions for which a NIMBY facility may make participants worst-off position and outgroup conditions for which this possibility is denied, the right angular gyrus was activated in both conditions. The amygdala was activated only in the ingroup, and the vmPFC exhibited a stronger tendency in the ingroup. We concluded that the cognitive-neural processes in judgments on NIMBY facilities are common to both decision-making to avoid the worst-off position for others and for oneself and moral judgments between the majority and the minority.


Assuntos
Julgamento , Córtex Pré-Frontal , Humanos , Tonsila do Cerebelo , Princípios Morais , Lobo Parietal , Imageamento por Ressonância Magnética
8.
ACS Infect Dis ; 8(3): 400-410, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35112852

RESUMO

The current worldwide emergence of carbapenem-resistant enterobacterales (CREs) constitutes an important growing clinical and public health threat. Acquired carbapenemases are the most important determinants of resistance to carbapenems. In the development of the previously reported tricyclic ß-lactam skeleton which exhibits potent antibacterial activities against several problematic ß-lactamase-producing CREs without a ß-lactamase inhibitor, we found that these activities were reduced against clinical isolates with resistance mechanisms other than ß-lactamase production. These mechanisms were the reduction of outer membrane permeability with the production of ß-lactamases and the insertion of four amino acids into penicillin-binding protein 3. Here, we report the discovery of a potent compound that overcomes these resistance mechanisms by the conversion of the alkoxyimino moiety of the aminothiazole side chain in which a hydrophilic functional group is introduced and the carboxylic acid of the alkoxyimino moiety is converted to reduce the negative charge of the whole molecule from 2 to 1. This potent tricyclic ß-lactam is a promising drug candidate for infectious diseases caused by CREs due to its potent therapeutic efficacy in the neutropenic mouse lung infection model and low frequency of producing spontaneously resistant mutants.


Assuntos
Carbapenêmicos , beta-Lactamas , Aminoácidos , Animais , Carbapenêmicos/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas/genética , Permeabilidade , Inibidores de beta-Lactamases/farmacologia , beta-Lactamas/farmacologia
9.
J Pharmacol Exp Ther ; 336(3): 743-50, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21098091

RESUMO

Transient receptor potential vanilloid 1 (TRPV1) is activated by a variety of stimulations, such as endogenous ligands and low pH, and is believed to play a role in pain transmission. TRPV1 antagonists have been reported to be effective in several animal pain models; however, some compounds induce hyperthermia in animals and humans. We discovered the novel TRPV1 antagonist (R)-N-(1-methyl-2-oxo-1,2,3,4-tetrahydro-7-quinolyl)-2-[(2-methylpyrrolidin-1-yl)methyl]biphenyl-4-carboxamide (AS1928370) in our laboratory. AS1928370 bound to the resiniferatoxin-binding site on TRPV1 and inhibited capsaicin-mediated inward currents with an IC50 value of 32.5 nM. Although AS1928370 inhibited the capsaicin-induced Ca²(+) flux in human and rat TRPV1-expressing cells, the inhibitory effect on proton-induced Ca²(+) flux was extremely small. In addition, AS1928370 showed no inhibitory effects on transient receptor potential vanilloid 4, transient receptor potential ankyrin 1, and transient receptor potential melastatin 8 in concentrations up to 10 µM. AS1928370 improved capsaicin-induced secondary hyperalgesia and mechanical allodynia in an L5/L6 spinal nerve ligation model in rats with respective ED50 values of 0.17 and 0.26 mg/kg p.o. Furthermore, AS1928370 alleviated inflammatory pain in a complete Freund's adjuvant model at 10 mg/kg p.o. AS1928370 had no effect on rectal body temperature up to 10 mg/kg p.o., although a significant hypothermic effect was noted at 30 mg/kg p.o. In addition, AS1928370 showed no significant effect on motor coordination. These results suggest that blockage of the TRPV1 receptor without affecting the proton-mediated TRPV1 activation is a promising approach to treating neuropathic pain because of the potential wide safety margin against hyperthermic effects. As such, compounds such as ASP1928370 may have potential as new analgesic agents for treating neuropathic pain.


Assuntos
Analgésicos/uso terapêutico , Benzamidas/uso terapêutico , Febre , Neuralgia/tratamento farmacológico , Medição da Dor/efeitos dos fármacos , Quinolonas/uso terapêutico , Canais de Cátion TRPV/antagonistas & inibidores , Analgésicos/farmacologia , Animais , Benzamidas/química , Benzamidas/farmacologia , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Febre/induzido quimicamente , Células HEK293 , Humanos , Masculino , Neuralgia/fisiopatologia , Dor/tratamento farmacológico , Dor/fisiopatologia , Medição da Dor/métodos , Ligação Proteica/fisiologia , Quinolonas/química , Quinolonas/farmacologia , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPV/fisiologia
10.
Int Immunol ; 22(3): 179-89, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20139174

RESUMO

CD4(+)CD25(+) regulatory T (Treg) cells cause immune suppression by inhibiting T cell effector functions and play pivotal roles not only in self-tolerance but also in immune response to parasitic microbial pathogens. Mycobacteria are major parasitic bacterial pathogens, but the role of CD4(+)CD25(+) Treg cells in mycobacterial infection is not yet defined. In this study we found that, at the early stage of infection, depletion of CD25(+) cells reduced both bacterial load and granuloma formation in mice infected with Mycobacterium tuberculosis strains, such as M. tuberculosis Erdman or M. tuberculosis Kurono. However, at a later stage of infection, bacterial burden and histopathology were similar regardless of depletion of CD25(+) cells. Severe combined immunodeficient (SCID) mice reconstituted with CD4(+)CD25(-) T cells alone or a combination of CD4(+)CD25(+) and CD4(+)CD25(-) T cells showed similar bacterial loads and survival kinetics after infection with M. tuberculosis Erdman. Consistent with in vivo data, in vitro studies revealed that mycobacterial antigens, purified protein derivative of tuberculin (PPD), failed to induce the suppressive function of CD4(+)CD25(+) Treg cells to CD4(+)CD25(-) effector T cells, as demonstrated by the lack of response of CD4(+)CD25(+) T cells to PPD, in mice chronically infected with Mycobacterium bovis bacillus Calmette-Guérin and M. tuberculosis. Our data show that CD4(+)CD25(+) Treg cells have a transient effect at the early stage of mycobacterial infection but, contrary to the expectation, have little impact on the overall course of infection.


Assuntos
Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Tuberculose/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Separação Celular , Feminino , Citometria de Fluxo , Subunidade alfa de Receptor de Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos SCID , Mycobacterium tuberculosis/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Tuberculina , Tuberculose/metabolismo
11.
Biol Pharm Bull ; 34(7): 1105-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21720020

RESUMO

Transient receptor potential vanilloid 1 (TRPV1) is primarily expressed in central and peripheral terminals of non-myelinated primary afferent neurons. We previously showed that AS1928370, a novel TRPV1 antagonist that can prevent ligand-induced activation but not proton-induced activation, ameliorates neuropathic pain in rats without hyperthermic effect. In this study, we investigated its analgesic profile in mice. AS1928370 showed good oral bioavailability and high penetration into the brain and spinal cord in mice. The mean plasma-to-brain and plasma-to-spinal cord ratios were 4.3 and 3.5, respectively. Pretreatment with AS1928370 significantly suppressed both capsaicin-induced acute pain and withdrawal response in hot plate test at 10-30 mg/kg per os (p.o.). At lower oral doses (0.3-1.0 mg/kg), AS1928370 improved mechanical allodynia in mice undergoing spinal nerve ligation. Intrathecal administration of AS1928370 (30 µg/body) also significantly suppressed mechanical allodynia. In addition, AS1928370 showed no effect on locomotor activity up to 30 mg/kg p.o. These results suggest that spinal TRPV1 has an important role in the transmission of neuropathic pain and that the central nervous system (CNS) penetrant TRPV1 receptor antagonist AS1928370 is a promising candidate for treating neuropathic pain.


Assuntos
Benzamidas/farmacologia , Hiperalgesia/prevenção & controle , Neuralgia/prevenção & controle , Quinolonas/farmacologia , Canais de Cátion TRPV/antagonistas & inibidores , Animais , Benzamidas/administração & dosagem , Benzamidas/farmacocinética , Capsaicina/farmacologia , Modelos Animais de Doenças , Injeções Espinhais , Camundongos , Neuralgia/induzido quimicamente , Quinolonas/administração & dosagem , Quinolonas/farmacocinética , Distribuição Tecidual
12.
Gan To Kagaku Ryoho ; 38(9): 1513-5, 2011 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-21918352

RESUMO

There are still no effective treatments against advanced hepatocarcinoma. One case of advanced hepatocarcinoma with multiple lung metastases, successfully treated with UFT, is reported here. After TAE in another hospital, the patient was refered to our hospital for treatment of multiple lung metastases. PIVKA-II and AFP decreased to normal levels after UFT was administered, and the multiple lung metastases disappeared as well. There are 13 cases including this one in which UFT was effective for hepatocarcinoma with multiple lung metastases. UFT is a possible home treatment because it is an orally administered anti-cancer drug that improves the patient's QOL. As UFT is one of the effective treatments for advanced hepatocarcinoma, it will be necessary to accumulate more data concerning its use, to apply it in the future.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Masculino , Indução de Remissão , Tegafur/uso terapêutico , Tomografia Computadorizada por Raios X , Uracila/uso terapêutico
13.
J Med Chem ; 64(13): 9496-9512, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34143627

RESUMO

Coadministration of ß-lactam and ß-lactamase inhibitor (BLI) is one of the well-established therapeutic measures for bacterial infections caused by ß-lactam-resistant Gram-negative bacteria, whereas we have only two options for orally active BLI, clavulanic acid and sulbactam. Furthermore, these BLIs are losing their clinical usefulness because of the spread of new ß-lactamases, including extended-spectrum ß-lactamases (ESBLs) belonging to class A ß-lactamases, class C and D ß-lactamases, and carbapenemases, which are hardly or not inhibited by these classical BLIs. From the viewpoints of medical cost and burden of healthcare personnel, oral therapy offers many advantages. In our search for novel diazabicyclooctane (DBO) BLIs possessing a thio-functional group at the C2 position, we discovered a 2-sulfinyl-DBO derivative (2), which restores the antibacterial activities of an orally available third-generation cephalosporin, ceftibuten (CTB), against various serine ß-lactamase-producing strains including carbapenem-resistant Enterobacteriaceae (CRE). It can be orally absorbed via the ester prodrug modification and exhibits in vivo efficacy in a combination with CTB.


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Ciclo-Octanos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Compostos Azabicíclicos/síntese química , Compostos Azabicíclicos/química , Ciclo-Octanos/síntese química , Ciclo-Octanos/química , Relação Dose-Resposta a Droga , Descoberta de Drogas , Enterobacteriaceae/enzimologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Serina/antagonistas & inibidores , Serina/metabolismo , Relação Estrutura-Atividade , Inibidores de beta-Lactamases/síntese química , Inibidores de beta-Lactamases/química
14.
Biol Pharm Bull ; 33(1): 67-71, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20045938

RESUMO

Dorsal root ganglia (DRG) are recognized as one of the organs which are damaged in peripheral sensory diabetic neuropathy. In an experimental animal model, the alteration of the mRNA expression level of neurotrophins, their receptors and neuronal cytoskeletal protein have been reported. In this study, we examined whether these changes are improved by treatment with the aldose reductase inhibitor, zenarestat, in early-stage diabetic neuropathy of streptozotocin (STZ)-induced diabetic rats. Two weeks after the induction of diabetes mellitus by STZ treatment, zenarestat or a vehicle were given orally for two weeks. After the zenarestat treatment, the mRNA expression levels of neurotrophin receptors and neuronal cytoskeletal proteins in dorsal root ganglia were determined with a real-time polymerase chain reaction (PCR) method. Compared with the expression level of normal rats, a significant increase in Trk-C and Talpha1 alpha-tubulin and a decrease in neurofilament H mRNA expression level were observed in the DRG of STZ rats, while there were no significant changes in Trk-A, Trk-B, p75, neurofilament L, neurofilament M and betaIII tubulin mRNA expression. Zenarestat treatment significantly ameliorated the abnormal increase in Trk-C mRNA expression level. These data suggest that hyperactivation of the polyol pathway induces a deficit in neurotropism on peripheral sensory diabetic neuropathy.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Proteínas do Citoesqueleto/metabolismo , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Gânglios Espinais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Animais , Proteínas do Citoesqueleto/genética , Inibidores Enzimáticos/farmacologia , Gânglios Espinais/efeitos dos fármacos , Masculino , Proteínas do Tecido Nervoso/genética , Proteínas de Neurofilamentos/genética , Proteínas de Neurofilamentos/metabolismo , Neurônios/metabolismo , Polímeros/metabolismo , Quinazolinas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Receptores de Fator de Crescimento Neural/efeitos dos fármacos , Receptores de Fator de Crescimento Neural/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
15.
ACS Infect Dis ; 6(11): 3034-3047, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33147950

RESUMO

By the emergence and worldwide spread of multi-drug-resistant Gram-negative bacteria, there have been growing demands for efficacious drugs to cure these resistant infections. The key mechanism for resistance to ß-lactam antibiotics is the production of ß-lactamases, which hydrolyze and deactivate ß-lactams. Diazabicyclooctane (DBO) analogs play an important role as one of the new classes of ß-lactamase inhibitors (BLIs), and several compounds such as avibactam (AVI) have been approved by the FDA, along with many derivatives under clinical or preclinical development. Although these compounds have a similar amide substituent at the C2 position, we have recently reported the synthesis of novel DBO analogs which possess a thio functional group. This structural modification enhances the ability to restore the antimicrobial activities of cefixime (CMF) against pathogens producing classes A, C, and D serine ß-lactamases compared with AVI and expands the structural tolerance at the six position. Furthermore, some of these analogs showed intrinsic microbial activities based on multipenicillin binding protein (PBP) inhibition. This is the unique feature which has never been observed in DBOs. One of our DBOs had a pharmacokinetic profile comparable to that of other DBOs. These results indicate that the introduction of a thio functional group into DBO is a novel and effective modification to discover a clinically useful new BLI.


Assuntos
beta-Lactamases , beta-Lactamas , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Serina , beta-Lactamas/farmacologia
16.
Tohoku J Exp Med ; 219(3): 257-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19851055

RESUMO

There exists latent tuberculosis, in which small numbers of tubercle bacilli remain viable in the host without visible granulomatous lesions. As few data exist on the mechanisms of latent tuberculosis, it is important to examine latent tuberculosis in terms of pathogenesis and efficacy of chemotherapy. As a first step, we used green fluorescent protein (GFP)-introduced H37Rv Mycobacterium tuberculosis to establish latent tuberculosis in the guinea pig that provides one of the best animal models of tuberculosis. We inoculated the guinea pigs subcutaneously with 100 or 1,000 colony-forming unit (CFU) of tubercle bacilli. During the 300-day follow-up period after infection, there were no clinical signs of disease, suggesting a lack of visible granulomatous lesions. In fact, upon necropsy, no macroscopic tuberculous lesions were recognized, but histopathological examination of the lung, spleen and liver revealed microgranulomas consisting of epithelioid macrophages and lymphocytes without central necrosis. Importantly, photon imaging visualized granulomatous lesions corresponding to these histologically apparent microgranulomas. Tuberculin skin testing of infected guinea pigs showed strong positivity (> or = 10 mm induration) until the end of the experiments. Real-time PCR analysis showed a significant increase in the expression levels of interferon-gamma, tumor necrosis factor-alpha, interleukin-12, and inducible nitric oxide synthase mRNAs in infected lung tissues after 300 days (P < 0.01). As human samples are hardly available to study latent tuberculosis, our guinea pig model would be useful for examining the pathogenesis and molecular mechanisms of latent tuberculosis as well as for monitoring the results of chemotherapy with green fluorescence emission of tubercle bacilli.


Assuntos
Proteínas de Fluorescência Verde/metabolismo , Cobaias/microbiologia , Tuberculose Latente/microbiologia , Tuberculose Latente/patologia , Mycobacterium tuberculosis/fisiologia , Animais , Diagnóstico por Imagem , Modelos Animais de Doenças , Fígado/microbiologia , Fígado/patologia , Pulmão/microbiologia , Pulmão/patologia , Especificidade de Órgãos , Fótons , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tela Subcutânea/microbiologia , Tela Subcutânea/patologia , Teste Tuberculínico
17.
J Antibiot (Tokyo) ; 61(5): 330-3, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18654001

RESUMO

Neoechinulin A, an alkaloid from Eurotium rubrum, can protect neuronal PC12 cells against cytotoxicity of a potent oxidant, peroxynitrite. Because involvement of peroxynitrite has been suggested in the pathogenesis of Parkinson's disease, we assessed whether this alkaloid could also protect PC12 cells from the cytocidal action of 1-methyl-4-phenylpyridine (MPP+), a neurotoxin capable of provoking acute Parkinson's-like neurodegeneration in humans. Neoechinulin A could protect PC12 cells from MPP+ cytotoxicity without protecting against mitochondrial complex I dysfunction, suggesting the alkaloid can ameliorate downstream events of mitochondrial failure. Thus, neoechinulin A has the potential to intervene in this progressive neurodegeneration.


Assuntos
1-Metil-4-fenilpiridínio/antagonistas & inibidores , 1-Metil-4-fenilpiridínio/toxicidade , Alcaloides Indólicos/farmacologia , Fármacos Neuroprotetores/farmacologia , Piperazinas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo I de Transporte de Elétrons/metabolismo , Células PC12 , Ácido Peroxinitroso/antagonistas & inibidores , Ácido Peroxinitroso/toxicidade , Ratos
18.
Eur J Med Chem ; 155: 847-868, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29960205

RESUMO

The structure-activity relationship (SAR) for a novel series of catechol conjugated siderophore cephalosporins is described with their in vitro activities against multi-drug resistant Gram-negative pathogens including Pseudomonas aeruginosa, Acinetobacter baumannii, Stenotrophomonas maltophilia and Enterobacteriaceae. Cefiderocol (3) was one of the best molecules which displayed well-balanced and potent activities against multi-drug resistant Gram-negative pathogens including carbapenem resistant bacteria among the prepared compounds with the modified C-7 side chain and the modified C-3 side chain. Cefiderocol (3) is a highly promising parenteral cephalosporin for the treatment of multi-drug resistant Gram-negative infection.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Cefalosporinas/síntese química , Cefalosporinas/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Cefiderocol
19.
J Antibiot (Tokyo) ; 60(10): 614-21, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17965477

RESUMO

Neoechinulin A, an alkaloid from Eurotium rubrum Hiji025, protected neuronal PC12 cells against cell death induced by peroxynitrite derived from SIN-1 (3-(4-morpholinyl)sydnonimine hydrochloride). In this study, we investigated the structure-activity relationships of neoechinulin A and a set of its analogues by using assays to measure anti-nitration and antioxidant activities and cytoprotection against SIN-1-induced PC12 cell death. The presence of the diketopiperazine ring was essential for both the antioxidant and anti-nitration activities of neoechinulin A derivatives. Nevertheless, a derivative lacking the diketopiperazine ring could still protect PC12 cells against SIN-1 cytotoxicity. An acyclic analogue completely lost the cytoprotective effect while retaining its antioxidant/anti-nitration activities. Pre-incubation of the cells with neoechinulin A for at least 12 hours was essential for the cells to gain SIN-1 resistance. These results suggest that neoechinulin A endows the cells with cytoprotection through a biological effect different from the apparent antioxidant/anti-nitration activities.


Assuntos
Citoproteção/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Ácido Peroxinitroso/antagonistas & inibidores , Ácido Peroxinitroso/toxicidade , Piperazinas/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Indicadores e Reagentes , Alcaloides Indólicos/química , Luminol/química , Luminol/metabolismo , Molsidomina/análogos & derivados , Molsidomina/farmacologia , NADPH Desidrogenase/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Oxirredução , Células PC12 , Ácido Peroxinitroso/metabolismo , Piperazinas/química , Ratos , Espécies Reativas de Nitrogênio/metabolismo , Relação Estrutura-Atividade
20.
Neuropharmacology ; 126: 97-107, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28859883

RESUMO

Lysophosphatidic acid (LPA) is a bioactive lipid that acts via at least six G protein-coupled receptors, LPA receptors 1-6 (LPA1-6), for various physiological functions. We examined (1) whether LPA5 is involved in pain signaling in the spinal cord; and (2) the pharmacological effects of a novel LPA5 antagonist on intrathecal prostaglandin (PG)- and (S)-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-induced allodynia, and neuropathic and inflammatory pain in rodents. Intrathecal injection of a selective LPA5 agonist, geranylgeranyl diphosphate, and a non-selective agonist, LPA, induced allodynia in wild type, but not in LPA5 knockout mice. These novel results suggest that LPA5 is important for pain signal transmission in the spinal cord. AS2717638 (6,7-dimethoxy-2-(5-methyl-1,2-benzoxazol-3-yl)-4-(piperidin-1-ylcarbonyl)isoquinolin-1(2H)-one) bound to the LPA-binding site on LPA5 and selectively inhibited LPA-induced cyclic adenosine monophosphate accumulation in human LPA5-but not LPA1-, 2-, or 3-expressing cells. Further, oral administration of AS2717638 inhibited LPA5 agonist-induced allodynia in mice. AS2717638 also significantly improved PGE2-, PGF2α-, and AMPA-induced allodynia, while both pregabalin and duloxetine alleviated only PGE2-induced allodynia in mice. Similarly, AS2717638 significantly ameliorated static mechanical allodynia and thermal hyperalgesia in rat models of chronic constriction injury (CCI)-induced neuropathic pain. AS2717638 also showed analgesic effects in a rat model of inflammatory pain. These findings suggest that LPA5 antagonists elicit broad analgesic effects against both neuropathic and inflammatory pain. Accordingly, pharmacological LPA5 antagonists are attractive development candidates for potential novel pain therapies.


Assuntos
Analgésicos/farmacologia , Benzoxazóis/farmacologia , Isoquinolinas/farmacologia , Dor/metabolismo , Dor/prevenção & controle , Piperidinas/farmacologia , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidores , Animais , Células Cultivadas , AMP Cíclico/metabolismo , Feminino , Hiperalgesia/induzido quimicamente , Hiperalgesia/prevenção & controle , Inflamação/complicações , Injeções Espinhais , Lisofosfolipídeos/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuralgia , Limiar da Dor/efeitos dos fármacos , Fosfatos de Poli-Isoprenil/administração & dosagem , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Receptores de Ácidos Lisofosfatídicos/genética
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