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1.
BMC Infect Dis ; 15: 571, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26675423

RESUMO

BACKGROUND: Penicillinase-producing Neisseria gonorroheae (PPNG) was first isolated in 1976. PPNG strains carrying bla TEM-1 and bla TEM-135 gene have been described in different countries. Recently, a novel bla TEM-220 allele was detected in PPNG isolates carrying Toronto/Rio plasmid. The prevalence and characteristics of TEM-220 strains worldwide are unknown, and therefore, it needs to be studied. The purpose of this study was to detect bla TEM-220 gene in PPNG strains possessing Toronto/Rio plasmid over a period of ten years in Argentina, and to evaluate the proportion of isolates producing non-TEM-220 containing the T539C substitution in the bla TEM allele. METHODS: One hundred and fifty one PPNG isolates carrying Toronto/Rio plasmid were studied between 2002 and 2011. A mismatch amplification mutation assay (MAMA) PCR was used to identify the T539C substitution in the bla TEM allele and a MAMA-PCR protocol was developed to detect the G547A substitution in the bla TEM-220. The reference agar dilution method of the Clinical and Laboratory Standard Institute (CLSI) was used for susceptibility testing to five ß-lactams antibiotics, ciprofloxacin, tetracycline and azithromycin. In all TEM-220-producing isolates, the whole bla TEM gene was sequenced and the isolates were typed using N. gonorroheae multiantigen sequence typing (NG-MAST). RESULTS: MAMA PCR successfully identified the G547A substitution in the bla TEM-220 allele. The proportion of isolates that possessed the bla TEM-220 allele was 2.6 %, and 93.2 % MAMA TEM-220 PCR-negative isolates showed the T539C substitution in the bla TEM gene. No differences in the susceptibility to five beta-lactam antibiotics tested were observed in PPNG isolates TEM-220-producing and PPNG isolates carrying the T539C substitution in the bla TEM gene. All TEM-220 isolates were indistinguishable by NG-MAST. CONCLUSION: This is the first study which shows the prevalence of bla TEM-220 in N. gonorrhoeae isolates carrying Toronto/Rio plasmid in Argentina. Although the bla TEM-220 allele does not appear to be associated with an extended spectrum beta-lactamase (ESBL) phenotype of resistance, a single nucleotide polymorphism added to the bla TEM-220 or bla TEM containing the T539C substitution could lead to the emergence of ESBL. Thus, it is imperative to investigate in surveillance programs, not only the plasmid type in PPNG isolates and the bla TEM allele associated, but phenotypical characteristics and geographical distribution of isolates.


Assuntos
Neisseria gonorrhoeae/genética , Penicilinase/metabolismo , beta-Lactamases/genética , Antibacterianos/farmacologia , Argentina , Ciprofloxacina/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Mutação , Neisseria gonorrhoeae/isolamento & purificação , Neisseria gonorrhoeae/patogenicidade , Plasmídeos , Prevalência , beta-Lactamas/farmacologia
2.
Bioorg Med Chem ; 21(21): 6264-73, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24075145

RESUMO

The last two decades have provided a large weight of preclinical data implicating the neurokinin-1 receptor (NK1) and its cognate ligand substance P (SP) in a broad range of both central and peripheral disease conditions. However, to date, only the NK1 receptor antagonist aprepitant has been approved as a therapeutic and this is to prevent chemotherapy-induced nausea & vomiting (CINV). The belief remained that the full therapeutic potential of NK1 receptor antagonists had yet to be realized; therefore clinical evidence that NK1 receptor antagonists may be effective in major depression disorder, resulted in a significant further investment in discovering novel CNS penetrant druggable NK1 receptor antagonists to address this condition. At GlaxoSmithKline after the discovery of casopitant, that went on to demonstrate efficacy as a novel antidepressant in the clinic, additional novel analogues of this NK1 receptor antagonist were designed to further enhance its drug developability characteristics. Herein, we therefore describe the discovery process and the vivo pharmacological and pharmacokinetic profile of the new NK1 receptor antagonist 3a (also called orvepitant), selected as clinical candidate and further progressed into clinical studies for major depressive disorder. Moreover, molecular modeling studies enabled us to improve the pharmacophore model of the NK1 receptor antagonists with the identification of a region able to accommodate a variety of heterocycle moieties.


Assuntos
Antidepressivos/química , Antagonistas dos Receptores de Neurocinina-1/química , Receptores da Neurocinina-1/química , Animais , Antidepressivos/síntese química , Antidepressivos/farmacocinética , Comportamento Animal/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Células CHO , Cricetinae , Cricetulus , Cães , Feminino , Gerbillinae , Meia-Vida , Humanos , Masculino , Modelos Moleculares , Conformação Molecular , Antagonistas dos Receptores de Neurocinina-1/síntese química , Antagonistas dos Receptores de Neurocinina-1/farmacocinética , Piperazinas/química , Piperidinas/síntese química , Piperidinas/química , Piperidinas/farmacocinética , Ligação Proteica , Ratos , Receptores da Neurocinina-1/genética , Receptores da Neurocinina-1/metabolismo
3.
Alzheimers Dement (N Y) ; 8(1): e12274, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35415206

RESUMO

Introduction: The neuronal mechanism driving Alzheimer's disease (AD) is incompletely understood. Methods: Immunohistochemistry, pharmacology, biochemistry, and behavioral testing are employed in two pathological contexts-AD and a transgenic mouse model-to investigate T14, a 14mer peptide, as a key signaling molecule in the neuropathology. Results: T14 increases in AD brains as the disease progresses and is conspicuous in 5XFAD mice, where its immunoreactivity corresponds to that seen in AD: neurons immunoreactive for T14 in proximity to T14-immunoreactive plaques. NBP14 is a cyclized version of T14, which dose-dependently displaces binding of its linear counterpart to alpha-7 nicotinic receptors in AD brains. In 5XFAD mice, intranasal NBP14 for 14 weeks decreases brain amyloid and restores novel object recognition to that in wild-types. Discussion: These findings indicate that the T14 system, for which the signaling pathway is described here, contributes to the neuropathological process and that NBP14 warrants consideration for its therapeutic potential.

4.
Bioorg Med Chem Lett ; 21(18): 5562-7, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21831639

RESUMO

The hypothalamic peptides orexin-A and orexin-B are potent agonists of two G-protein coupled receptors, namely the OX(1) and the OX(2) receptor. These receptors are widely distributed, though differentially, in the rat brain. In particular, the OX(1) receptor is highly expressed throughout the hypothalamus, whilst the OX(2) receptor is mainly located in the ventral posterior nucleus. A large body of compelling evidence, both pre-clinical and clinical, suggests that the orexin system is profoundly implicated in sleep disorders. In particular, modulation of the orexin receptors activation by appropriate antagonists was proven to be an efficacious strategy for the treatment of insomnia in man. A novel, drug-like bis-amido piperidine derivative was identified as potent dual OX(1) and OX(2) receptor antagonists, highly effective in a pre-clinical model of sleep.


Assuntos
Descoberta de Drogas , Piperidinas/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Neuropeptídeos/antagonistas & inibidores , Transtornos do Sono-Vigília/tratamento farmacológico , Animais , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Receptores de Orexina , Piperidinas/síntese química , Piperidinas/química , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
5.
J Med Chem ; 64(9): 5931-5955, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33890770

RESUMO

Transient receptor potential cation channel subfamily M member 5 (TRPM5) is a nonselective monovalent cation channel activated by intracellular Ca2+ increase. Within the gastrointestinal system, TRPM5 is expressed in the stoma, small intestine, and colon. In the search for a selective agonist of TRPM5 possessing in vivo gastrointestinal prokinetic activity, a high-throughput screening was performed and compound 1 was identified as a promising hit. Hit validation and hit to lead activities led to the discovery of a series of benzo[d]isothiazole derivatives. Among these, compounds 61 and 64 showed nanomolar activity and excellent selectivity (>100-fold) versus related cation channels. The in vivo drug metabolism and pharmacokinetic profile of compound 64 was found to be ideal for a compound acting locally at the intestinal level, with minimal absorption into systemic circulation. Compound 64 was tested in vivo in a mouse motility assay at 100 mg/kg, and demonstrated increased prokinetic activity.


Assuntos
Benzotiazóis/química , Benzotiazóis/farmacologia , Trato Gastrointestinal/metabolismo , Ensaios de Triagem em Larga Escala , Canais de Cátion TRPM/agonistas , Animais , Benzotiazóis/metabolismo , Benzotiazóis/farmacocinética , Desenho de Fármacos , Trato Gastrointestinal/efeitos dos fármacos , Humanos , Masculino , Camundongos , Terapia de Alvo Molecular , Reprodutibilidade dos Testes , Distribuição Tecidual
6.
Bioorg Med Chem Lett ; 20(17): 5069-73, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20674357

RESUMO

A novel imidazobenzazepine template (5a) with potent dual H(1)/5-HT(2A) antagonist activity was identified. Application of a zwitterionic approach to this poorly selective and poorly developable starting point successfully delivered a class of high quality leads, 3-[4-(3-R(1)-2-R-5H-imidazo[1,2-b][2]benzazepin-11-yl)-1-piperazinyl]-2,2-dimethylpropanoic acids (e.g., 9, 19, 20, and 21), characterized by potent and balanced H(1)/5-HT(2A) receptor antagonist activities and good developability profiles.


Assuntos
Receptor 5-HT1A de Serotonina/efeitos dos fármacos , Receptor 5-HT2A de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/uso terapêutico , Transtornos do Sono-Vigília/tratamento farmacológico , Humanos
7.
Diagn Microbiol Infect Dis ; 53(2): 157-60, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16168614

RESUMO

The synergistic potential of ceftazidime plus amikacin or levofloxacin was assessed against 61 Pseudomonas aeruginosa isolates with variable susceptibility patterns to the 3 antibiotics. A checkerboard broth method and a disk diffusion method were used and compared. The latter, also easy to perform as a triple-disk assay, could be a helpful laboratory screening tool for drug synergism to drive possible combination treatments.


Assuntos
Anti-Infecciosos/farmacologia , Sinergismo Farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Amicacina/farmacologia , Ceftazidima/farmacologia , Quimioterapia Combinada , Imunodifusão/métodos , Levofloxacino , Testes de Sensibilidade Microbiana , Ofloxacino/farmacologia
8.
Neuropsychopharmacology ; 37(9): 1999-2011, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22569505

RESUMO

Orexins (OX) and their receptors (OXR) modulate feeding, arousal, stress, and drug abuse. Neural systems that motivate and reinforce drug abuse may also underlie compulsive food seeking and intake. Therefore, the effects of GSK1059865 (5-bromo-N-[(2S,5S)-1-(3-fluoro-2-methoxybenzoyl)-5-methylpiperidin-2-yl]methyl-pyridin-2-amine), a selective OX(1)R antagonist, JNJ-10397049 (N-(2,4-dibromophenyl)-N'-[(4S,5S)-2,2-dimethyl-4-phenyl-1,3-dioxan-5-yl]urea), a selective OX(2)R antagonist, and SB-649868 (N-[((2S)-1-{[5-(4-fluorophenyl)-2-methyl-1,3-thiazol-4-yl]carbonyl}-2-piperidinyl)methyl]-1-benzofuran-4-carboxamide), a dual OX(1)/OX(2)R antagonist were evaluated in a binge eating (BE) model in female rats. BE of highly palatable food (HPF) was evoked by three cycles of food restriction followed by stress, elicited by exposing rats to HPF, but preventing them from having access to it for 15 min. Pharmacokinetic assessments of all compounds were obtained under the same experimental conditions used for the behavioral experiments. Topiramate was used as the reference compound as it selectively blocks BE in rats and humans. Dose-related thresholds for sleep-inducing effects of the OXR antagonists were measured using polysomnography in parallel experiments. SB-649868 and GSK1059865, but not JNJ-10397049, selectively reduced BE for HPF without affecting standard food pellet intake, at doses that did not induce sleep. These results indicate, for the first time, a major role of OX(1)R mechanisms in BE, suggesting that selective antagonism at OX(1)R could represent a novel pharmacological treatment for BE and possibly other eating disorders with a compulsive component.


Assuntos
Bulimia/metabolismo , Comportamento Compulsivo , Ingestão de Alimentos/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Receptores de Neuropeptídeos/fisiologia , Animais , Bulimia/tratamento farmacológico , Bulimia/psicologia , Comportamento Compulsivo/tratamento farmacológico , Comportamento Compulsivo/psicologia , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/psicologia , Feminino , Frutose/análogos & derivados , Frutose/farmacologia , Frutose/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Masculino , Neuropeptídeos/farmacologia , Receptores de Orexina , Orexinas , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Neuropeptídeos/agonistas , Receptores de Neuropeptídeos/antagonistas & inibidores , Esquema de Reforço , Fatores Sexuais , Topiramato , Células Tumorais Cultivadas
9.
PLoS One ; 6(1): e16406, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21307957

RESUMO

Orexins are neuro-modulatory peptides involved in the control of diverse physiological functions through interaction with two receptors, orexin-1 (OX1R) and orexin-2 (OX2R). Recent evidence in pre-clinical models points toward a putative dichotomic role of the two receptors, with OX2R predominantly involved in the regulation of the sleep/wake cycle and arousal, and the OX1R being more specifically involved in reward processing and motivated behaviour. However, the specific neural substrates underlying these distinct processes in the rat brain remain to be elucidated. Here we used functional magnetic resonance imaging (fMRI) in the rat to map the modulatory effect of selective OXR blockade on the functional response produced by D-amphetamine, a psychostimulant and arousing drug that stimulates orexigenic activity. OXR blockade was produced by GSK1059865 and JNJ1037049, two novel OX1R and OX2R antagonists with unprecedented selectivity at the counter receptor type. Both drugs inhibited the functional response to D-amphetamine albeit with distinct neuroanatomical patterns: GSK1059865 focally modulated functional responses in striatal terminals, whereas JNJ1037049 induced a widespread pattern of attenuation characterised by a prominent cortical involvement. At the same doses tested in the fMRI study, JNJ1037049 exhibited robust hypnotic properties, while GSK1059865 failed to display significant sleep-promoting effects, but significantly reduced drug-seeking behaviour in cocaine-induced conditioned place preference. Collectively, these findings highlight an essential contribution of the OX2R in modulating cortical activity and arousal, an effect that is consistent with the robust hypnotic effect exhibited by JNJ1037049. The subcortical and striatal pattern observed with GSK1059865 represent a possible neurofunctional correlate for the modulatory role of OX1R in controlling reward-processing and goal-oriented behaviours in the rat.


Assuntos
Ciclos de Atividade/fisiologia , Aminopiridinas/farmacologia , Mapeamento Encefálico , Dioxanos/farmacologia , Imageamento por Ressonância Magnética , Motivação/fisiologia , Compostos de Fenilureia/farmacologia , Piperidinas/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Neuropeptídeos/antagonistas & inibidores , Recompensa , Anfetamina/farmacologia , Animais , Comportamento Animal , Receptores de Orexina , Ratos
10.
J Med Chem ; 53(21): 7778-95, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20942472

RESUMO

Histamine H(1) and serotonin 5-HT(2A) receptors mediate two different mechanisms involved in sleep regulation: H(1) antagonists are sleep inducers, while 5-HT(2A) antagonists are sleep maintainers. Starting from 9'a, a novel spirotetracyclic compound endowed with good H(1)/5-HT(2A) potency but poor selectivity, very high Cli, and a poor P450 profile, a specific optimization strategy was set up. In particular, we investigated the possibility of introducing appropriate amino acid moieties to optimize the developability profile of the series. Following this zwitterionic approach, we were able to identify several advanced leads (51, 65, and 73) with potent dual H(1)/5-HT(2A) activity and appropriate developability profiles. These compounds exhibited efficacy as hypnotic agents in a rat telemetric sleep model with minimal effective doses in the range 3-10 mg/kg po.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Antagonistas dos Receptores Histamínicos H1/síntese química , Hipnóticos e Sedativos/síntese química , Receptor 5-HT2A de Serotonina/metabolismo , Antagonistas do Receptor 5-HT2 de Serotonina/síntese química , Sono/efeitos dos fármacos , Compostos de Espiro/síntese química , Animais , Disponibilidade Biológica , Encéfalo/metabolismo , Linhagem Celular , Córtex Cerebral/metabolismo , Cricetinae , Cricetulus , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Antagonistas dos Receptores Histamínicos H1/química , Antagonistas dos Receptores Histamínicos H1/farmacologia , Humanos , Hipnóticos e Sedativos/química , Hipnóticos e Sedativos/farmacologia , Masculino , Microssomos Hepáticos/metabolismo , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Antagonistas do Receptor 5-HT2 de Serotonina/química , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Transtornos do Sono-Vigília/tratamento farmacológico , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
11.
Arch. argent. dermatol ; 65(2): 54-56, may-2015. ilus
Artigo em Espanhol | LILACS | ID: lil-784828

RESUMO

Se presenta el caso de un paciente de 74 años, agricultor, oriundo de Paraguay, quien consultó por ulceraciones genitales de 2 meses de evolución, asintomáticas. Se realizaron exámenes microbiológicos (directo y cultivo) y biopsia de una de las lesiones, hallándose Paracoccidioides sp. Se inicia tratamiento con itraconazol 200 mg/día con buena respuesta. Existen escasas publicaciones acerca de esta forma de presentación. Planteamos la necesidad de considerarla en el diagnóstico diferencial de las patologías genitales en áreas endémicas...


Assuntos
Humanos , Paracoccidioidomicose/diagnóstico , Antifúngicos
12.
Antimicrob Agents Chemother ; 47(2): 816-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12543701

RESUMO

Levofloxacin showed comparable in vitro susceptibility to ciprofloxacin among Enterobacteriaceae, Pseudomonas aeruginosa, enterococci, and Staphylococcus aureus, while greater susceptibility was observed in Stenotrophomonas maltophilia and Staphylococcus epidermidis, mainly when oxacillin resistant. The susceptibility of Streptococcus pneumoniae to levofloxacin reached 99%.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Ciprofloxacina/farmacologia , Levofloxacino , Testes de Sensibilidade Microbiana , Ofloxacino/farmacologia , Bactérias/isolamento & purificação
14.
Bol. Inst. Med. Reg ; 20/21/22: 45-48, 1999.
Artigo em Espanhol | LILACS | ID: lil-424369

RESUMO

Se realizó un estudio prospectivo de los BGNNF, excluyendo Pseudomonas aeruginosa, aislados en el Laboratorio del Hospital "Dr. Julio C. Perrando" de la ciudad de Resistencia (Argentina) con el objeto de conocer su frecuencia y susceptibilidad antimicrobiana. La identificación bacteriana fue realizada mediante pruebas bioquímicas. El mayor porcentaje de BGNNF aislados procedía de sangre (25 por ciento), secreciones respiratoria y orina (23,9 por ciento), siendo Acinetobacter baumannii (34,7 por ciento), Pseudomonas fluorescens/P putida (15,2 por ciento), Stenotrophomonas maltophllia (9,7 por ciento) y Burkholderia cepacia (8,7 por ciento) las especies aisladas con más frecuencia. Se estudió además la distribución de las distintas cepas según el producto patológico y área de hospitalización, realizándose pruebas de sensibilidad a los antimicrobianos a cepas con mayor porcentaje de aislamiento. Se concluye que: 1- los BGNNF son aislados con mayor frecuencia de pacientes internados y comprometidos que de los ambulatorios y 2- la antibioticoterapia debiera ser administrada según el informe del laboratorio de bacteriología


Assuntos
Humanos , Acinetobacter , Burkholderia cepacia , Flavobacterium , Infecções por Bactérias Gram-Negativas , Pseudomonas fluorescens , Pseudomonas putida , Sphingobacterium , Stenotrophomonas maltophilia , Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas , Hospitais Públicos , Pacientes Internados , Testes de Sensibilidade Microbiana , Estudos Prospectivos , Pseudomonas
15.
s.l; s.n; 1989. 11 p. ilus, tab.
Não convencional em Espanhol | LILACS | ID: lil-70572

RESUMO

Calculo de personal para el laboratorio del Hospital Julio C.Perrando


Assuntos
Laboratórios , Argentina , Hospitais com 300 a 499 Leitos , Hospitais Gerais
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