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1.
Chem Biodivers ; 21(8): e202400638, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38837284

RESUMO

QSAR studies on the number of compounds tested as S. aureus inhibitors were performed using an interactive Online Chemical Database and Modeling Environment (OCHEM) web platform. The predictive ability of the developed consensus QSAR model was q2=0.79±0.02. The consensus prediction for the external evaluation set afforded high predictive power (q2=0.82±0.03). The models were applied to screen a virtual chemical library with anti-S. aureus activity. Six promising new bicyclic trifluoromethylated pyrroles were identified, synthesized and evaluated in vitro against S. aureus, E. coli, and A. baumannii for their antibacterial activity and against C. albicans, C. krusei and C. glabrata for their antifungal activity. The synthesized compounds were characterized by 1H, 19F, and 13C NMR and elemental analysis. The antimicrobial activity assessment indicated that trifluoromethylated pyrroles 9 and 11 demonstrated the greatest antibacterial and antifungal effects against all the tested pathogens, especially against multidrug-resistant strains. The acute toxicity of the compounds to Daphnia magna ranged from 1.21 to 33.39 mg/L (moderately and slightly toxic). Based on the docking results, it can be suggested that the antibacterial and antifungal effects of the compounds can be explained by the inhibition of bacterial wall component synthesis.


Assuntos
Antibacterianos , Antifúngicos , Testes de Sensibilidade Microbiana , Pirróis , Relação Quantitativa Estrutura-Atividade , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Pirróis/química , Pirróis/farmacologia , Pirróis/síntese química , Staphylococcus aureus/efeitos dos fármacos , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Animais , Estrutura Molecular , Daphnia/efeitos dos fármacos , Simulação de Acoplamento Molecular , Acinetobacter baumannii/efeitos dos fármacos , Simulação por Computador , Candida albicans/efeitos dos fármacos
2.
Acta Trop ; 242: 106924, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37037291

RESUMO

Atorvastatin (AVA) is a third-generation statin with several pleiotropic effects, considered the last synthetic pharmaceutical blockbuster. Recently, our group described the effects of AVA on DNA damage prevention and against Trypanosoma cruzi infection. In this study, our aim was to evaluate the efficacy, safety, and in silico pharmacokinetic profile of four hybrids of aminoquinolines with AVA 4a-d against T. cruzi using in vitro and in silico models. These synthetic compounds were designed by hybridization of the pentapyrrolic moiety of AVA with the aminoquinolinic unit of chloroquine or primaquine. Pharmacokinetics (ADME) and toxicity parameters were predicted by SwissADME, admetSAR and LAZAR in silico algorithms. The trypanocidal activity of AVA-quinoline hybrids were evaluated in vitro against amastigotes and trypomastigotes of T. cruzi, from Y (Tc II) and Tulahuen (Tc VI) strains. In vitro cardiocytotoxicity was assessed using primary cultures of mouse embryonic cardiac cells and in vitro hepatocytotoxicity on bidimensional and 3D-cultured HepG2 cells. Genotoxicity was evaluated by Ames test and micronucleus assay. Despite the overall good in silico ADMET profile, all tested compounds were predicted to be hepatotoxic. All hybrid derivatives presented high trypanocidal activity, against both trypomastigote and intracellular forms of T. cruzi, presenting EC50's lower than 1 µM besides superior selectivity than the reference drug, without evidences of cardiotoxicity in vitro. The compounds 4a and 4b presented a time-dependent toxicity in monolayer culture of HepG2 but no detectable toxic effects in their spheroids, opposing to the in silico prediction. We can conclude that the AVA-aminoquinoline hybrids presented a hit profile as antiparasitic agents in synthetic pharmaceutical innovation platforms.


Assuntos
Antimaláricos , Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Animais , Camundongos , Atorvastatina/farmacologia , Atorvastatina/uso terapêutico , Pirróis/farmacologia , Pirróis/uso terapêutico , Doença de Chagas/parasitologia , Aminoquinolinas/farmacologia , Antimaláricos/farmacologia , Dano ao DNA , Preparações Farmacêuticas , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
3.
SLAS Discov ; 26(3): 336-344, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33208020

RESUMO

The reuse of preexisting small molecules for a novel emerging disease threat is a rapid measure to discover unknown applications for previously validated therapies. A pertinent and recent example where such a strategy could be employed is in the fight against coronavirus disease 2019 (COVID-19). Therapies designed or discovered to target viral proteins also have off-target effects on the host proteome when employed in a complex physiological environment. This study aims to assess these host cell targets for a panel of FDA-approved antiviral compounds including remdesivir, using the cellular thermal shift assay (CETSA) coupled with mass spectrometry (CETSA MS) in noninfected cells. CETSA MS is a powerful method to delineate direct and indirect interactions between small molecules and protein targets in intact cells. Biologically active compounds can induce changes in thermal stability, in their primary binding partners, and in proteins that in turn interact with the direct targets. Such engagement of host targets by antiviral drugs may contribute to the clinical effect against the virus but can also constitute a liability. We present here a comparative study of CETSA molecular target engagement fingerprints of antiviral drugs to better understand the link between off-targets and efficacy.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Antivirais/farmacologia , Proteínas de Ciclo Celular/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Adenosina/análogos & derivados , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Reposicionamento de Medicamentos , Furanos/farmacologia , Células Hep G2 , Humanos , Espectrometria de Massas , Proteômica/métodos , Pirróis/farmacologia , Triazinas/farmacologia , Estados Unidos , United States Food and Drug Administration , Tratamento Farmacológico da COVID-19
4.
J Med Chem ; 62(13): 6315-6329, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31246452

RESUMO

Reduction of mitochondrial oxidative stress-mediated diseases is an important pharmaceutical objective in recent biomedical research. In this context, a series of novel pyrrolobenzoxazines (PyBs) framework with enormous diversity (compounds 5a-w) was synthesized by employing a low-temperature greener pathway, and antioxidant property of the synthesized compounds was successfully demonstrated on preclinical model goat heart mitochondria, in vitro. Copper-ascorbate (Cu-As) was utilized as an oxidative stress generator. Out of screened PyBs, the compound possessing -OH and -OMe groups on benzene nucleus along with pyrrolobenzoxazine core moiety (compound 5w) displayed magnificent antioxidant property with a minimum effective dose of 66 µM during the biochemical assessment. The ameliorative effect of synthesized pyrrolobenzoxazine moiety on levels of biomarkers of oxidative stress, antioxidant enzyme, activities of Krebs cycle and respiratory chain enzymes, mitochondrial morphology, and Ca2+ permeability of mitochondrial membrane was investigated in the presence of Cu-As. Furthermore, the binding mode of Cu-As by compound 5w was explored successfully using isothermal titration calorimetry (ITC) analysis.


Assuntos
Benzoxazinas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Pirróis/farmacologia , Animais , Ácido Ascórbico/farmacologia , Benzoxazinas/síntese química , Biomarcadores/metabolismo , Ciclo do Ácido Cítrico/efeitos dos fármacos , Cobre/farmacologia , Sequestradores de Radicais Livres/síntese química , Glutationa/metabolismo , Cabras , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Membranas Mitocondriais/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Pirróis/síntese química , Superóxido Dismutase/metabolismo
5.
Pestic Biochem Physiol ; 156: 123-128, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027571

RESUMO

Sclerotinia homoeocarpa causes dollar spot disease on turfgrass and is a serious problem on many species worldwide. Fludioxonil, a phenylpyrrole fungicide, is not currently registered for dollar spot control in China. In this study, the baseline sensitivity to fludioxonil was established using an in vitro assay for 105 isolates of S. homoeocarpa collected from 10 locations in different regions of China. Results indicate that the frequency distribution of effective concentration for 50% inhibition of mycelial growth (EC50) values of the S. homoeocarpa isolates was unimodal (W = 0.9847, P = .2730). The mean EC50 value was 0.0020 ±â€¯0.0006 µg/ml with a range from 0.0003 to 0.0035 µg/ml. A total of 7 fludioxonil-resistant mutants were obtained in laboratory, the mutants were stable in fludioxonil sensitivity after the 10th transfer, with resistance factor (RF) ranging from 4.320 to >13,901.4. The mutants showed a positive cross-resistance between fludioxonil and the dicarboximide fungicide iprodione, but not propiconazole, fluazinam, and thiophanate-methyl. When mycelial growth rate, pathogenicity and osmotic sensitivity were assessed, the mutants decreased in the fitness compared with their parental isolates. Sequence alignment of the histidine kinase gene Shos1 revealed a 13-bp fragment deletion only in one mutant, no mutations were observed on Shos1 in the rest resistant mutants.


Assuntos
Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Dioxóis/farmacologia , Fungicidas Industriais/farmacologia , Pirróis/farmacologia , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Aminopiridinas/farmacologia , Ascomicetos/genética , China , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/genética , Hidantoínas/farmacologia , Mutação/genética , Tiofanato/farmacologia , Triazóis/farmacologia
6.
Eur J Drug Metab Pharmacokinet ; 44(2): 217-227, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30361928

RESUMO

BACKGROUND AND OBJECTIVES: It was recently proposed that CYP-mediated drug-drug interactions (DDIs) of vonoprazan with clopidogrel and prasugrel can attenuate the antiplatelet actions of the latter two drugs. Clopidogrel is metabolized to the pharmacologically active metabolite H4 and its isomers by multiple CYPs, including CYP2C19 and CYP3A4. Therefore, to investigate the possibility of CYP-based DDIs, in vitro metabolic inhibition studies using CYP probe substrates or radiolabeled clopidogrel and human liver microsomes (HLMs) were conducted in this work. METHODS: Reversible inhibition studies focusing on the effects of vonoprazan on CYP marker activities and the formation of the [14C]clopidogrel metabolite H4 were conducted with and without pre-incubation using HLMs. Time-dependent inhibition (TDI) kinetics were also measured. RESULTS: It was found that vonoprazan is not a significant direct inhibitor of any CYP isoforms (IC50 ≥ 16 µM), but shows the potential for TDI of CYP2B6, CYP2C19, and CYP3A4/5. This TDI was weaker than the inhibition induced by the corresponding reference inhibitors ticlopidine, esomeprazole, and verapamil, based on the measured potencies (kinact/KI ratio and the R2 value). In a more direct in vitro experiment, vonoprazan levels of up to 10 µM (a 100-fold higher concentration than the plasma Cmax of 75.9 nM after taking 20 mg once daily for 7 days) did not suppress the formation of the active metabolite H4 or other oxidative metabolites of [14C]clopidogrel in a reversible or time-dependent manner. Additionally, an assessment of clinical trials and post-marketing data suggested no evidence of a DDI between vonoprazan and clopidogrel. CONCLUSIONS: The body of evidence shows that the pharmacodynamic DDI reported between vonoprazan and clopidogrel is unlikely to be caused by the inhibition of CYP2B6, CYP2C19, or CYP3A4/5 by vonoprazan.


Assuntos
Clopidogrel/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Pirróis/farmacologia , Sulfonamidas/farmacologia , Clopidogrel/metabolismo , Inibidores das Enzimas do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas/fisiologia , Humanos , Microssomos Hepáticos/metabolismo , Inibidores da Agregação Plaquetária/metabolismo , Pirróis/metabolismo , Sulfonamidas/metabolismo
8.
Sci Rep ; 8(1): 14421, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30258062

RESUMO

DNA damaging therapies can spur the formation of therapy-related cancers, due to mis-repair of lesions they create in non-cancerous cells. This risk may be amplified in patients with impaired DNA damage responses. We disabled key DNA damage response pathways using genetic and pharmacological approaches, and assessed the impact of these deficiencies on the mutagenicity of chemotherapy drugs or the "Smac mimetic" GDC-0152, which kills tumor cells by targeting XIAP, cIAP1 and 2. Doxorubicin and cisplatin provoked mutations in more surviving cells deficient in ATM, p53 or the homologous recombination effector RAD51 than in wild type cells, but suppressing non-homologous end joining (NHEJ) by disabling DNA-PKcs prevented chemotherapy-induced mutagenesis. Vincristine-induced mutagenesis required p53 and DNA-PKcs but was not affected by ATM status, consistent with it provoking ATM-independent p53-mediated activation of caspases and CAD, which creates DNA lesions in surviving cells that could be mis-repaired by NHEJ. Encouragingly, GDC-0152 failed to stimulate mutations in cells with proficient or defective DNA damage response pathways. This study highlights the elevated oncogenic risk associated with treating DNA repair-deficient patients with genotoxic anti-cancer therapies, and suggests a potential advantage for Smac mimetic drugs over traditional therapies: a reduced risk of therapy-related cancers.


Assuntos
Materiais Biomiméticos/farmacologia , Cicloexanos/farmacologia , Dano ao DNA , Sistemas de Liberação de Medicamentos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Mitocondriais , Proteínas de Neoplasias , Neoplasias , Pirróis/farmacologia , Proteínas Reguladoras de Apoptose , Linhagem Celular Tumoral , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Células HEK293 , Humanos , Mutagênese/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia
9.
Pestic Biochem Physiol ; 139: 32-39, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28595919

RESUMO

Bipolaris maydis (anamorph: Cochliobolus heterostrophus) is the causal agent of Southern Corn Leaf Blight (SCLB), leading to huge annually losses worldwide. Although fludioxonil, a phenylpyrrole fungicide with a broad spectrum of activity, was introduced in the 1990s, no baseline sensitivity has been established for B. maydis. One hundred field isolates were used to establish a baseline sensitivity of B. maydis against fludioxonil during 2015-2016. The results showed that the baseline sensitivity was distributed as a unimodal curve with a mean EC50 value of 0.044±0.022µgmL-1. With repeated exposure to fludioxonil, a total of five fludioxonil-resistant mutants (RF>100, RF=Resistance factor) were obtained in the laboratory. Compared with the parental isolates, the five fludioxonil-resistant mutants showed decreased fitness in sporulation and virulence, and exhibited different features of sensitivity to various stresses (oxidation and osmotic pressure, cell membrane and cell wall inhibitors), but not in mycelial growth on PDA without stress amendation. The five fludioxonil-resistant mutants showed a positive cross-resistance between fludioxonil and the dicarboximide fungicide procymidone, but not between fludioxonil and boscalid or fluazinam. All mutants exhibited stable resistance to fludioxonil after 10 transfers, as indicated by resistance factor values that ranged from 116.82 to 445.59. When treated with 1.0 M NaCl, all the fludioxonil-resistant mutants showed greater mycelial glycerol content than corresponding parental isolates. Sequencing alignment results of Bmos1 indicated that mutant R27-5 had a single point mutation (Z1125K), while the mutant R104 had a 34-bp deletion fragment between the codons of amino acid residues 1125 to 1236 and encodes a putative attenuated 1133-AA protein. The 34-bp deletion fragment led to not only a 11-AA deletion(DNAVNQKLAVR), but also the resulting frameshift mutation and early stop. The mutations of R27-5 and R104 were located in the Rec domain of the Bmos1 gene. No mutations at the Bmos1 were detected in the other three resistant mutants R27-1, R27-2 and R32.


Assuntos
Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Dioxóis/farmacologia , Fungicidas Industriais/farmacologia , Pirróis/farmacologia , Ascomicetos/genética , Farmacorresistência Fúngica/genética , Mutação da Fase de Leitura/genética , Proteínas Fúngicas/genética , Mutação/genética , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Medição de Risco , Virulência
10.
BMC Med ; 14(1): 201, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27923360

RESUMO

Intra-tumour heterogeneity is a common molecular phenomenon in metastatic clear cell renal carcinoma (mRCC), representing the genetic complexity of a tumour with multiple metastatic sites. The present commentary discusses the observed phenomena of phenotypic intra-tumour heterogeneity in mRCC patients treated with the tyrosine kinase inhibitors sunitinib or pazopanib. Here, drug response can be different on the level of each evaluated metastasis in the individual patient. This questions the currently used radiologic staging systems of RECIST criteria and demands for a modification of radiologic response assessment with the consequence of a patient-tailored therapy in the clinical setting.Please see related article: http://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-016-0729-9 .


Assuntos
Carcinoma de Células Renais , Indóis/farmacologia , Neoplasias Renais , Pirimidinas/farmacologia , Pirróis/farmacologia , Sulfonamidas/farmacologia , Antineoplásicos/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Heterogeneidade Genética , Humanos , Indazóis , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/patologia , Metástase Neoplásica , Testes Farmacogenômicos , Proteínas Tirosina Quinases/antagonistas & inibidores , Critérios de Avaliação de Resposta em Tumores Sólidos , Sunitinibe
11.
Chembiochem ; 17(20): 1905-1910, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27477066

RESUMO

One of the major goals in DNA-based personalized medicine is the development of sequence-specific small molecules to target the genome. SAHA-PIPs belong to such class of small molecule. In the context of the complex eukaryotic genome, the differential biological effects of SAHA-PIPs are unclear. This question can be addressed by identifying the binding regions across the genome; however, it is a challenge to enrich small-molecule-bound DNA without chemical crosslinking. Here, we developed a method that employs high-throughput sequencing to map the binding area of small molecules throughout the chromatinized human genome. Analysis of the sequenced data confirmed the presence of specific binding sites for SAHA-PIPs from the enriched sequence reads. Mapping the binding sites and enriched regions on the human genome clarifies the reason for the distinct biological effects of SAHA-PIP. This approach will be useful for identifying the function of other small molecules on a large scale.


Assuntos
DNA/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Ácidos Hidroxâmicos/farmacologia , Imidazóis/farmacologia , Nylons/farmacologia , Pirróis/farmacologia , Sítios de Ligação/efeitos dos fármacos , DNA/química , DNA/genética , Humanos , Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/metabolismo , Imidazóis/química , Imidazóis/metabolismo , Estrutura Molecular , Nylons/química , Nylons/metabolismo , Pirróis/química , Pirróis/metabolismo , Vorinostat
12.
Cancer Chemother Pharmacol ; 78(1): 209-16, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27295055

RESUMO

PURPOSE: Therapeutic drug monitoring (TDM) is being considered as a tool to individualise sunitinib treatment of gastrointestinal stromal tumours (GIST). Here, we used computer simulations to assess the expected impact of sunitinib TDM on the clinical outcome of patients with GIST. METHODS: Monte Carlo simulations were performed in R, based on previously published pharmacokinetic-pharmacodynamic models. Clinical trials with dose-limiting toxicity and patient dropout were simulated to establish the study size required to obtain sufficient statistical power for comparison of TDM-guided and fixed dosing. RESULTS: The simulations revealed that TDM might increase time to tumour progression by about 1-2 months (15-31 %) in eligible patients. However, the number of subjects required for a sufficient statistical power to quantify clinical benefit of TDM guided is likely to be prohibitively high (>1000). CONCLUSION: Although data from randomised clinical trials on the clinical impact of sunitinib TDM are lacking, our findings support implementation of sunitinib TDM in clinical practice. For rare cancers with well-defined exposure-response relationships, modelling and simulation might allow the optimisation of dosing strategies when clinical trials cannot be performed due to low number of patients.


Assuntos
Antineoplásicos/administração & dosagem , Monitoramento de Medicamentos/métodos , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Indóis/administração & dosagem , Pirróis/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Simulação por Computador , Progressão da Doença , Relação Dose-Resposta a Droga , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Humanos , Indóis/farmacocinética , Indóis/farmacologia , Modelos Biológicos , Método de Monte Carlo , Pirróis/farmacocinética , Pirróis/farmacologia , Sunitinibe , Fatores de Tempo , Resultado do Tratamento
13.
Ter Arkh ; 88(12): 4-10, 2016.
Artigo em Russo | MEDLINE | ID: mdl-28139553

RESUMO

The paper considers a current strategy, international and Russian recommendations for the pharmacotherapy of rheumatoid arthritis (RA), one of the most common and severe human immune-mediated inflammatory diseases. It emphasizes the need for early diagnosis and therapy with disease-modifying antirheumatic drugs, primarily methotrexate (MT), starting at the onset of the disease, and careful monitoring of therapeutic effectiveness, allowing RA remission to be achieved with a treatment-to-target strategy. The author discusses recent RA pharmacotherapy advances that are related to the rational use of MT, biological agents, and the new targeted JAK inhibitor tofacitinib.


Assuntos
Antirreumáticos/farmacologia , Artrite Reumatoide , Conduta do Tratamento Medicamentoso , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Monitoramento de Medicamentos/métodos , Diagnóstico Precoce , Humanos , Indução de Remissão/métodos
14.
Med Phys ; 42(8): 4965-73, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26233222

RESUMO

PURPOSE: It is now recognized that the tumor vasculature is in part responsible for regulating tumor responses to radiation therapy. However, the extent to which radiation-based vascular damage contributes to tumor cell death remains unknown. In this work, quantitative ultrasound spectroscopy (QUS) methods were used to investigate the acute responses of tumors to radiation-based vascular treatments. METHODS: Tumor xenografts (MDA-MB-231) were treated with single radiation doses of 2 or 8 Gy alone, or in combination with pharmacological agents that modulate vascular radiosensitivity. The midband fit, the slope, and the 0-MHz intercept QUS parameters were obtained from a linear-regression fit to the averaged power spectrum of frequency-dependent ultrasound backscatter and were used to quantify acute tumor responses following treatment administration. Power spectrums were extracted from raw volumetric radio-frequency ultrasound data obtained before and 24 h following treatment administration. These parameters have previously been correlated to tumor cell death. Staining using in situ end labeling, carbonic anhydrase 9 and cluster of differentiation 31 of tumor sections were used to assess cell death, oxygenation, and vasculature distributions, respectively. RESULTS: Results indicate a significant midband fit QUS parameter increases of 3.2 ± 0.3 dBr and 5.4 ± 0.5 dBr for tumors treated with 2 and 8 Gy radiation combined with the antiangiogenic agent Sunitinib, respectively. In contrast, tumors treated with radiation alone demonstrated a significant midband fit increase of 4.4 ± 0.3 dBr at 8 Gy only. Preadministration of basic fibroblast growth factor, an endothelial radioprotector, acted to minimize tumor response following single large doses of radiation. Immunohistochemical analysis was in general agreement with QUS findings; an R(2) of 0.9 was observed when quantified cell death was correlated with changes in midband fit. CONCLUSIONS: Results from QUS analysis presented in this study confirm that acute tumor response is linked to a vascular effect following high doses of radiation therapy. Overall, this is in agreement with previous reports suggesting that acute tumor radiation response is regulated by a vascular-driven response. Data also suggest that Sunitinib may enhance tumor radiosensitivity through a vascular remodeling process, and that QUS may be sensitive to changes in tissue properties associated with vascular remodeling. Finally, the work also demonstrates the ability of QUS methods to monitor response to radiation-based vascular strategies.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Análise Espectral/métodos , Ultrassonografia/métodos , Indutores da Angiogênese/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Quimiorradioterapia , Fatores de Crescimento de Fibroblastos/farmacologia , Humanos , Imuno-Histoquímica , Indóis/farmacologia , Camundongos SCID , Transplante de Neoplasias , Oxigênio/metabolismo , Pirróis/farmacologia , Sunitinibe , Resultado do Tratamento
15.
Science ; 348(6232): 282-3, 2015 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-25883340
16.
Rev. latinoam. enferm ; 23(1): 98-105, Jan-Feb/2015. tab
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: lil-742021

RESUMO

OBJECTIVES: to evaluate the Nosocomial Infection Control Programs in hospital institutions regarding structure and process indicators. METHOD: this is a descriptive, exploratory and quantitative study conducted in 2013. The study population comprised 13 Nosocomial Infection Control Programs of health services in a Brazilian city of the state of São Paulo. Public domain instruments available in the Manual of Evaluation Indicators of Nosocomial Infection Control Practices were used. RESULTS: The indicators with the highest average compliance were "Evaluation of the Structure of the Nosocomial Infection Control Programs" (75%) and "Evaluation of the Epidemiological Surveillance System of Nosocomial Infection" (82%) and those with the lowest mean compliance scores were "Evaluation of Operational Guidelines" (58.97%) and "Evaluation of Activities of Control and Prevention of Nosocomial Infection" (60.29%). CONCLUSION: The use of indicators identified that, despite having produced knowledge about prevention and control of nosocomial infections, there is still a large gap between the practice and the recommendations. .


OBJETIVOS: avaliar os Programas de Controle de Infecção Hospitalar nas instituições hospitalares, quanto aos indicadores de estrutura e processo. MÉTODO: trata-se de um estudo descritivo, exploratório e quantitativo, realizado em 2013. A população foi composta por 13 Programas de Controle de Infecção Hospitalar de serviços de saúde, de uma cidade brasileira do interior paulista. Foram utilizados instrumentos de domínio público, disponibilizados no Manual de Indicadores de Avaliação de Práticas de Controle de Infecção Hospitalar. RESULTADOS: os indicadores com maior média de conformidade foram "Avaliação da Estrutura dos Programas de Controle de Infecção Hospitalar" (75%) e "Avaliação do Sistema de Vigilância Epidemiológica de Infecção Hospitalar" (82%) e os com menores médias foram "Avaliação das Diretrizes Operacionais" (58,97%) e "Avaliação das Atividades de Controle e Prevenção de Infecção Hospitalar" (60,29%). CONCLUSÃO: o uso de indicadores identificou que, apesar do conhecimento produzido sobre ações de prevenção e controle de infecções hospitalares, ainda existe um grande hiato entre prática e recomendações. .


OBJETIVOS: evaluar los Programas de Control de Infección Hospitalaria en las instituciones hospitalarias respecto a los indicadores de estructura y proceso. MÉTODO: se trata de un estudio descriptivo, exploratorio y cuantitativo, desarrollado en 2013. La población fue compuesta por 13 Programas de Control de Infección Hospitalaria de servicios de salud de una ciudad brasileña del interior paulista. Fueron utilizados instrumentos de dominio público, disponibles en el Manual de Indicadores de Evaluación de Prácticas de Control de Infección Hospitalaria. RESULTADOS: los indicadores con mayor promedio de conformidad fueron "Evaluación de la Estructura de los Programas de Control de Infección Hospitalaria" (75%) y "Evaluación del Sistema de Vigilancia Epidemiológica de Infección Hospitalaria" (82%) y aquellos con menores promedios "Evaluación de las Directivas Operacionales" (58,97%) y "Evaluación de las Actividades de Control y Prevención de Infección Hospitalaria" (60,29%). CONCLUSIÓN: el uso de indicadores posibilitó identificar que, a pesar del conocimiento producido sobre acciones de prevención y control de infecciones hospitalarias, todavía existe un gran hiato entre la práctica y las recomendaciones. .


Assuntos
Humanos , Masculino , Feminino , Idoso , Anlodipino/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Ácidos Heptanoicos/uso terapêutico , Hipertensão/tratamento farmacológico , Rim/fisiopatologia , Pirróis/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Anlodipino/farmacologia , Anti-Hipertensivos/farmacologia , Biomarcadores/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Cápsulas , Quimioterapia Combinada , Glucose/metabolismo , Ácidos Heptanoicos/farmacologia , Hipertensão/complicações , Hipertensão/fisiopatologia , Inflamação/patologia , Testes de Função Renal , Rim/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Análise Multivariada , Estresse Oxidativo/efeitos dos fármacos , Pirróis/farmacologia , Análise de Regressão , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/fisiopatologia
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 140: 344-55, 2015 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25615679

RESUMO

An orange colored pyrrole dihydrazone: Pyrrole-2,5-dicarboxaldehyde bis(oxaloyldihydrazone) (PDBO) has been synthesized by reaction of oxalic acid dihydrazide with 2,5 diformyl-1H-pyrrole and has been characterized by spectroscopic analysis (1H, 13C NMR, UV-visible, FT-IR and DART Mass). The properties of the compound has been evaluated using B3LYP functional and 6-31G(d,p)/6-311+G(d,p) basis set. The symmetric (3319, 3320 cm(-1)) and asymmetric (3389, 3382 cm(-1)) stretching wave number confirm free NH2 groups in PDBO. NBO analysis shows, inter/intra molecular interactions within the molecule. Topological parameters have been analyzed by QTAIM theory and provide the existence of intramolecular hydrogen bonding (N-H⋯O). The local reactivity descriptors analyses determine the reactive sites within molecule. The calculated first hyperpolarizability value (ß0=23.83×10(-30) esu) of pyrrole dihydrazone shows its suitability for non-linear optical (NLO) response. The preliminary bioassay suggested that the PDBO exhibits relatively good antibacterial and fungicidal activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, Candida albicans, Aspergillus niger. The local reactivity descriptors--Fukui functions (fk+, fk-), local softnesses (sk+, sk-) and electrophilicity indices (ωk+, ωk-) analyses have been used to determine the reactive sites within molecule.


Assuntos
Antibacterianos/química , Antifúngicos/química , Hidrazonas/química , Pirróis/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Fungos/efeitos dos fármacos , Humanos , Hidrazonas/farmacologia , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Micoses/tratamento farmacológico , Pirróis/farmacologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Antioxid Redox Signal ; 21(8): 1145-55, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-24597714

RESUMO

AIMS: The tumor microenvironment is characterized by a highly reducing redox status, a low pH, and hypoxia. Anti-angiogenic therapies for solid tumors frequently function in two steps: the transient normalization of structurally and functionally aberrant tumor blood vessels with increased blood perfusion, followed by the pruning of tumor blood vessels and the resultant cessation of nutrients and oxygen delivery required for tumor growth. Conventional anatomic or vascular imaging is impractical or insufficient to distinguish between the two steps of tumor response to anti-angiogenic therapies. Here, we investigated whether the noninvasive imaging of the tumor redox state and energy metabolism could be used to characterize anti-angiogenic drug-induced transient vascular normalization. RESULTS: Daily treatment of squamous cell carcinoma (SCCVII) tumor-bearing mice with the multi-tyrosine kinase inhibitor sunitinib resulted in a rapid decrease in tumor microvessel density and the suppression of tumor growth. Tumor pO2 imaging by electron paramagnetic resonance imaging showed a transient increase in tumor oxygenation after 2-4 days of sunitinib treatment, implying improved tumor perfusion. During this window of vascular normalization, magnetic resonance imaging of the redox status using an exogenously administered nitroxide probe and hyperpolarized (13)C MRI of the metabolic flux of pyruvate/lactate couple revealed an oxidative shift in tumor redox status. INNOVATION: Redox-sensitive metabolic couples can serve as noninvasive surrogate markers to identify the vascular normalization window in tumors with imaging techniques. CONCLUSION: A multimodal imaging approach to characterize physiological, metabolic, and redox changes in tumors is useful to distinguish between the different stages of anti-angiogenic treatment.


Assuntos
Inibidores da Angiogênese/farmacologia , Indóis/farmacologia , Neoplasias/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Pirróis/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Linhagem Celular Tumoral , Meios de Contraste/metabolismo , Óxidos N-Cíclicos/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Humanos , Indóis/uso terapêutico , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C3H , Camundongos Nus , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Oxirredução , Oxigênio/metabolismo , Pirróis/uso terapêutico , Ácido Pirúvico/metabolismo , Sunitinibe , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Eur J Med Chem ; 65: 240-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23721952

RESUMO

The 1,3-dipolar cycloaddition of azomethine ylides generated in situ from acenaphthenequinone and α-amino acids viz. 1,3-thiazolone-4-carboxylic acid and piperidine-2-carboxylic acid to a series of 1-methyl-3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones afforded novel spiro[5.2″]acenaphthene-1″-onespiro[6.3']-5'-arylmethylidene-1'-methylpiperidin-4'-one-7-aryltetrahydro-1H-pyrrolo[1,2-c][1,3]thiazoles and spiro[2.2″]acenaphthene-1″-onespiro[3.3']-5'-arylmethylidene-1'-methylpiperidin-4'-one-4-aryloctahydroindolizines respectively in quantitative yields. These compounds were evaluated for their AChE inhibitory activity and compound 3c was found to be the most potent with IC50 1.86 µmol/L.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Piperidinas/farmacologia , Pirróis/farmacologia , Tiazóis/farmacologia , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Electrophorus , Modelos Moleculares , Estrutura Molecular , Piperidinas/síntese química , Piperidinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
20.
J Chem Inf Model ; 53(6): 1463-74, 2013 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-23617317

RESUMO

Pharmacophoric mapping is a useful procedure to frame, especially when crystallographic receptor structures are unavailable as in ligand-based studies, the hypothetical site of interaction. In this study, 71 pyrrole derivatives active against M. tuberculosis were used to derive through a recent new 3-D QSAR protocol, 3-D QSAutogrid/R, several predictive 3-D QSAR models on compounds aligned by a previously reported pharmacophoric application. A final multiprobe (MP) 3-D QSAR model was then obtained configuring itself as a tool to derive pharmacophoric quantitative models. To stress the applicability of the described models, an external test set of unrelated and newly synthesized series of R-4-amino-3-isoxazolidinone derivatives found to be active at micromolar level against M. tuberculosis was used, and the predicted bioactivities were in good agreement with the experimental values. The 3-D QSAutogrid/R procedure proved to be able to correlate by a single multi-informative scenario the different activity molecular profiles thus confirming its usefulness in the rational drug design approach.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Pirróis/química , Pirróis/farmacologia , Relação Quantitativa Estrutura-Atividade , Desenho de Fármacos , Humanos , Modelos Moleculares , Oxazolidinonas/química , Oxazolidinonas/farmacologia , Tuberculose/tratamento farmacológico
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