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1.
Microbiology (Reading) ; 167(10)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34596506

RESUMO

Cachexia (CC) is a complex wasting syndrome that significantly affects life quality and life expectancy among cancer patients. Original studies, in which CC was induced in mouse models through inoculation with BaF and C26 tumour cells, demonstrated that CC development correlates with bacterial gut dysbiosis in these animals. In both cases, a common microbial signature was observed, based on the expansion of Enterobacteriaceae in the gut of CC animals. However, these two types of tumours induce unique microbial profiles, suggesting that different CC induction mechanisms significantly impact the outcome of gut dysbiosis. The present study sought to expand the scope of such analyses by characterizing the CC-associated dysbiosis that develops when mice are inoculated with Lewis lung carcinoma (LLC) cells, which constitutes one of the most widely employed mechanisms for CC induction. Interestingly, Enterobacteriaceae expansion is also observed in LLC-induced CC. However, the dysbiosis identified herein displays a more complex pattern, involving representatives from seven different bacterial phyla, which were consistently identified across successive levels of taxonomic hierarchy. These results are supported by a predictive analysis of gene content, which identified a series of functional/structural changes that potentially occur in the gut bacterial population of these animals, providing a complementary and alternative approach to microbiome analyses based solely on taxonomic classification.


Assuntos
Caquexia/microbiologia , Carcinoma Pulmonar de Lewis/patologia , Disbiose/microbiologia , Fezes/microbiologia , Transplante de Neoplasias/efeitos adversos , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Caquexia/etiologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Disbiose/etiologia , Microbioma Gastrointestinal , Camundongos , Filogenia
2.
Med Mycol ; 59(2): 197-200, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32692810

RESUMO

This paper describes a transcriptomic profiling of Paracoccidioides brasiliensis (Pb) performed with the aid of an RNA-seq-based approach, aimed at characterizing the general transcriptome in this human pathogenic fungus, responsible for paracoccidioidomycosis (PCM). Results confirm that ∼75% of the genes currently annotated in the P. brasiliensis genome are, in fact, transcribed in vivo and that ∼19% of them may display alternative isomorphs. Moreover, we identified 627 transcripts that do not match any gene currently mapped in the genome, represented by 114 coding transcripts (probably derived from previously unmapped protein-coding genes) and 513 noncoding RNAs (ncRNAs), including 203 long-noncoding RNAs (lncRNAs).


Assuntos
Perfilação da Expressão Gênica , Paracoccidioides/genética , RNA não Traduzido/genética , Genoma Fúngico , Humanos , Paracoccidioides/patogenicidade , Paracoccidioidomicose/microbiologia , Análise de Sequência de RNA , Transcriptoma
3.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073173

RESUMO

Autoinducer 2 (or AI-2) is one of the molecules used by bacteria to trigger the Quorum Sensing (QS) response, which activates expression of genes involved in a series of alternative mechanisms, when cells reach high population densities (including bioluminescence, motility, biofilm formation, stress resistance, and production of public goods, or pathogenicity factors, among others). Contrary to most autoinducers, AI-2 can induce QS responses in both Gram-negative and Gram-positive bacteria, and has been suggested to constitute a trans-specific system of bacterial communication, capable of affecting even bacteria that cannot produce this autoinducer. In this work, we demonstrate that the ethanologenic Gram-negative bacterium Zymomonas mobilis (a non-AI-2 producer) responds to exogenous AI-2 by modulating expression of genes involved in mechanisms typically associated with QS in other bacteria, such as motility, DNA repair, and nitrogen fixation. Interestingly, the metabolism of AI-2-induced Z. mobilis cells seems to favor ethanol production over biomass accumulation, probably as an adaptation to the high-energy demand of N2 fixation. This opens the possibility of employing AI-2 during the industrial production of second-generation ethanol, as a way to boost N2 fixation by these bacteria, which could reduce costs associated with the use of nitrogen-based fertilizers, without compromising ethanol production in industrial plants.


Assuntos
Etanol/metabolismo , Homosserina/análogos & derivados , Lactonas/farmacologia , Fixação de Nitrogênio/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Zymomonas/metabolismo , Homosserina/farmacologia
4.
Bioinformatics ; 34(3): 514-515, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28968637

RESUMO

Summary: This manuscript introduces and describes Dugong, a Docker image based on Ubuntu 16.04, which automates installation of more than 3500 bioinformatics tools (along with their respective libraries and dependencies), in alternative computational environments. The software operates through a user-friendly XFCE4 graphic interface that allows software management and installation by users not fully familiarized with the Linux command line and provides the Jupyter Notebook to assist in the delivery and exchange of consistent and reproducible protocols and results across laboratories, assisting in the development of open science projects. Availability and implementation: Source code and instructions for local installation are available at https://github.com/DugongBioinformatics, under the MIT open source license. Contact: Luiz.nunes@ufabc.edu.br.


Assuntos
Biologia Computacional/normas , Software , Biologia Computacional/métodos , Reprodutibilidade dos Testes
5.
J Antimicrob Chemother ; 73(2): 414-424, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29092042

RESUMO

Objectives: To characterize NAI-107 and related lantibiotics for their in vitro activity against Gram-negative pathogens, alone or in combination with polymyxin, and against non-dividing cells or biofilms of Staphylococcus aureus. NAI-107 was also evaluated for its propensity to select or induce self-resistance in Gram-positive bacteria. Methods: We used MIC determinations and chequerboard experiments to establish the antibacterial activity of the examined compounds against target microorganisms. Time-kill assays were used to evaluate killing of exponential and stationary-phase cells. The effects on biofilms (growth inhibition and biofilm eradication) were evaluated using biofilm-coated pegs. The frequency of spontaneous resistant mutants was evaluated by either direct plating or by continuous sub-culturing at 0.5 × MIC levels, followed by population analysis profiles. Results: The results showed that NAI-107 and its brominated variant are highly active against Neisseria gonorrhoeae and some other fastidious Gram-negative pathogens. Furthermore, all compounds strongly synergized with polymyxin against Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, and showed bactericidal activity. Surprisingly, NAI-107 alone was bactericidal against non-dividing A. baumannii cells. Against S. aureus, NAI-107 and related lantibiotics showed strong bactericidal activity against dividing and non-dividing cells. Activity was also observed against S. aureus biofilms. As expected for a lipid II binder, no significant resistance to NAI-107 was observed by direct plating or serial passages. Conclusions: Overall, the results of the current work, along with previously published results on the efficacy of NAI-107 in experimental models of infection, indicate that this lantibiotic represents a promising option in addressing the serious threat of antibiotic resistance.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Biofilmes/efeitos dos fármacos , Sinergismo Farmacológico , Bactérias Gram-Negativas/efeitos dos fármacos , Polimixinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos
6.
Biochemistry ; 56(5): 779-792, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28125217

RESUMO

Xylella fastidiosa is a plant-infecting bacillus, responsible for many important crop diseases, such as Pierce's disease of vineyards, citrus variegated chlorosis, and coffee leaf scorch (CLS), among others. Recent genomic comparisons involving two CLS-related strains, belonging to X. fastidiosa subsp. pauca, revealed that one of them carries a frameshift mutation that inactivates a gene encoding an oxidoreductase of the short-chain dehydrogenase/reductase (SDR) superfamily, which may play important roles in determining structural variations in bacterial glycans and glycoconjugates. However, the exact nature of this SDR has been a matter of controversy, as different annotations of X. fastidiosa genomes have implicated it in distinct reactions. To confirm the nature of this mutated SDR, a comparative analysis was initially performed, suggesting that it belongs to a subgroup of SDR decarboxylases, representing a UDP-xylose synthase (Uxs). Functional assays, using a recombinant derivative of this enzyme, confirmed its nature as XfUxs, and carbohydrate composition analyses, performed with lipopolysaccharide (LPS) molecules obtained from different strains, indicate that inactivation of the X. fastidiosa uxs gene affects the LPS structure among CLS-related X. fastidiosa strains. Finally, a comparative sequence analysis suggests that this mutation is likely to result in a morphological and evolutionary hallmark that differentiates two subgroups of CLS-related strains, which may influence interactions between these bacteria and their plant and/or insect hosts.


Assuntos
Carboxiliases/química , Evolução Molecular , Lipopolissacarídeos/química , Filogenia , Proteínas de Plantas/química , Xylella/genética , Sequência de Aminoácidos , Sequência de Bases , Carboxiliases/genética , Carboxiliases/metabolismo , Clonagem Molecular , Coffea/microbiologia , Escherichia coli/genética , Escherichia coli/metabolismo , Mutação da Fase de Leitura , Expressão Gênica , Hidrólise , Lipopolissacarídeos/biossíntese , Monossacarídeos/análise , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Xylella/classificação , Xylella/enzimologia , Xylella/isolamento & purificação
7.
Molecules ; 22(12)2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29194347

RESUMO

Natural products are a prolific source for the identification of new biologically active compounds. In the present work, we studied the in vitro and in vivo antimalarial efficacy and ADME-Tox profile of a molecular hybrid (AM1) between 4-aminoquinoline and a quinolizidine moiety derived from lupinine (Lupinus luteus). The aim was to find a compound endowed with the target product profile-1 (TCP-1: molecules that clear asexual blood-stage parasitaemia), proposed by the Medicine for Malaria Venture to accomplish the goal of malaria elimination/eradication. AM1 displayed a very attractive profile in terms of both in vitro and in vivo activity. By using standard in vitro antimalarial assays, AM1 showed low nanomolar inhibitory activity against chloroquine-sensitive and resistant P. falciparum strains (range IC50 16-53 nM), matched with a high potency against P. vivax field isolates (Mean IC50 29 nM). Low toxicity and additivity with artemisinin derivatives were also demonstrated in vitro. High in vivo oral efficacy was observed in both P.berghei and P. yoelii mouse models with IC50 values comparable or better than those of chloroquine. The metabolic stability in different species and the pharmacokinetic profile in the mouse model makes AM1 a compound worth further investigation as a potential novel schizonticidal agent.


Assuntos
Aminoquinolinas/química , Aminoquinolinas/farmacologia , Antimaláricos/química , Antimaláricos/toxicidade , Quinolizidinas/química , Quinolizidinas/farmacologia , Aminoquinolinas/toxicidade , Animais , Antimaláricos/farmacologia , Artemisininas/farmacologia , Cloroquina/farmacologia , Resistência a Medicamentos , Células HEK293 , Humanos , Concentração Inibidora 50 , Malária/tratamento farmacológico , Masculino , Camundongos , Parasitemia/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Plasmodium vivax/efeitos dos fármacos , Quinolizidinas/toxicidade , Esparteína/análogos & derivados , Esparteína/química , Esparteína/farmacologia
8.
Mol Genet Genomics ; 291(3): 1347-62, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26956010

RESUMO

Paracoccidioides brasiliensis is a thermodimorphic fungus associated with paracoccidioidomycosis (PCM), the most common systemic mycosis in Latin America. PCM treatment involves a long-term chemotherapeutic approach and relapses occur at an alarming frequency. Moreover, the emergence of strains with increased drug-resistance phenotypes puts constant pressure on the necessity to develop new alternatives to treat systemic mycoses. In this work, we show that the phenothiazine (PTZ) derivative thioridazine (TR) inhibits in vitro growth of P. brasiliensis yeasts at micromolar concentrations. We employed microarray hybridization to examine how TR affects gene expression in this fungus, identifying ~1800 genes that were modulated in response to this drug. Dataset evaluation showed that TR inhibits the expression of genes that control the onset of the cell wall integrity (CWI) response, hampering production of all major structural polysaccharides of the fungal cell wall (chitin, α-glucan and ß-glucan). Although TR and other PTZs have been shown to display antimicrobial activity by various mechanisms, inhibition of CWI signaling has not yet been reported for these drugs. Thus, TR may provide a novel approach to treat fungal infections by targeting cell wall biogenesis.


Assuntos
Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Paracoccidioides/efeitos dos fármacos , Tioridazina/farmacologia , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Polissacarídeos Fúngicos/biossíntese , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Paracoccidioides/genética , Paracoccidioidomicose/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos
9.
Antimicrob Agents Chemother ; 59(8): 4560-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25987631

RESUMO

A chemical derivative of the thiopeptide GE2270A, designated NAI003, was found to possess a substantially reduced antibacterial spectrum in comparison to the parent compound, being active against just a few Gram-positive bacteria. In particular, NAI003 retained low MICs against all tested isolates of Propionibacterium acnes and, to a lesser extent, against Enterococcus faecalis. Furthermore, NAI003 showed a time- and dose-dependent killing of both a clindamycin-resistant and a clindamycin-sensitive P. acnes isolate. Gel shift experiments indicated that, like the parent compound, NAI003 retained the ability to bind to elongation factors Tu (EF-Tus) derived from Escherichia coli, E. faecalis, or P. acnes, albeit with reduced efficiency. In contrast, EF-Tus derived from the NAI003-insensitive Staphylococcus aureus or Streptococcus pyogenes did not bind this compound. These results were confirmed by in vitro studies using a hybrid translation system, which indicated that NAI003 can inhibit most efficiently protein synthesis driven by the P. acnes EF-Tu. P. acnes mutants resistant to NAI003 were isolated by direct plating. With one exception, all analyzed strains carried mutations in the tuf gene, encoding EF-Tu. Because of its selective effect on P. acnes in comparison to resident skin flora, NAI003 represents a promising candidate for the topical treatment of acne, which has already completed a phase 1 clinical study.


Assuntos
Antibacterianos/farmacologia , Peptídeos Cíclicos/farmacologia , Propionibacterium acnes/efeitos dos fármacos , Tiazóis/farmacologia , Administração Tópica , Clindamicina/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Fator Tu de Elongação de Peptídeos/metabolismo , Propionibacterium acnes/metabolismo , Pele/microbiologia
10.
J Transl Med ; 13: 107, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25888743

RESUMO

BACKGROUND: Combined antiretroviral therapy has drastically reduced mortality and morbidity of HIV-infected individuals. Nevertheless long-term toxicity and appearance of viral resistance hampers the prolonged effectiveness of combination therapy, requiring a continuous input of drugs to replace those utilized in combination regimens. We here investigated the anti-HIV activity of novel derivatives of the suradista chemical class. METHODS: Compounds were tested on acute HIV-1 infection of activated peripheral blood mononuclear cells. HIV production was monitored by enzyme-linked immunosorbent assay measuring the protein p24 released in culture supernatants. Fusion assays were carried out to study the mechanism of action of these compounds. A modified version of a previously established recombinant vaccinia virus-based assay was used measuring activation of a reporter gene upon fusion of two distinct cell populations. Flow cytometry was performed in competition assays for the binding of several antibodies targeting different sites of the viral envelope glycoprotein gp120, or the receptor CD4, or the coreceptors CXCR4 and CCR5. RESULTS: Four compounds inhibited replication of a prototypic R5 (BaL) and X4 (IIIB) laboratory-adapted HIV-1 strain at low micromolar concentrations, in the absence of cytotoxicity. Approximately a ten fold greater activity was achieved against the X4 as compared to the R5 strain. The compounds blocked X4 and R5 HIV-1 fusion, a step of viral entry. This activity appeared specific for HIV-1, as entry of human herpesvirus 6 (HHV-6) and influenza virus was not substantially affected. Further investigation of the inhibitory mechanism revealed that these new molecules target the viral envelope, rather than the coreceptors, as previously shown for a congener of the same class characterized by a long plasmatic half-life. Indeed ND-4043, the most active compound, specifically competed with binding of monoclonal antibodies against the CD4-binding site (CD4-BS) and coreceptor-binding site (CoR-BS) of gp120. These compounds displayed broad anti-HIV activity, as they inhibited various primary R5, X4 and, importantly, dualtropic R5X4 HIV-1 isolates. Of the four derivatives tested, the dimeric compounds were consistently more potent than the monomeric ones. CONCLUSIONS: Given their unique features, these molecules represent promising candidates for further development and exploitation as anti-HIV therapeutics.


Assuntos
Inibidores da Fusão de HIV/farmacologia , HIV-1/fisiologia , Internalização do Vírus/efeitos dos fármacos , Células 3T3 , Animais , Antivirais/farmacologia , Benzilaminas , Morte Celular/efeitos dos fármacos , Linhagem Celular , Ciclamos , Cicloexanos/farmacologia , Citometria de Fluxo , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Maraviroc , Fusão de Membrana/efeitos dos fármacos , Camundongos , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Triazóis/farmacologia , Replicação Viral/efeitos dos fármacos
11.
Antimicrob Agents Chemother ; 58(4): 1922-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24419352

RESUMO

NAI-603 is a ramoplanin derivative designed to overcome the tolerability issues of the parent drug as a systemic agent. NAI-603 is highly active against aerobic and anaerobic Gram-positive bacteria, with MICs ranging from 0.008 to 8 µg/ml. MICs were not significantly affected by pH (range, 6 to 8), by inoculum up to 10(8) CFU/ml, or by addition of 50% human serum. Against staphylococci and enterococci, NAI-603 was rapidly bactericidal, with minimum bactericidal concentration (MBC)/MIC ratios never exceeding 4. The frequency of spontaneous resistance was low at 2× to 4× MIC (≤1×10(-6) to ≤1×10(-8)) and below the detection limit (about ≤1×10(-9)) at 8×MIC. Serial subcultures at 0.5×MIC yielded at most an 8-fold increase in MICs. In a systemic infection induced by methicillin-resistant Staphylococcus aureus (MRSA), the 50% effective dose (ED50) of intravenous (i.v.) NAI-603 was 0.4 mg/kg, lower than that of oral (p.o.) linezolid (1.4 mg/kg) and subcutaneous (s.c.) teicoplanin (1.4 mg/kg) or vancomycin (0.6 mg/kg). In neutropenic mice infected with vancomycin-resistant enterococci (VRE), the ED50s for NAI-603 were 1.1 to 1.6 mg/kg i.v., compared to 0.5 mg/kg i.v. of ramoplanin. The bactericidal activity was confirmed in vivo in the rat granuloma pouch model induced by MRSA, where NAI-603, at 40 mg/kg i.v., induced about a 2- to 3-log10-reduction in viable bacteria in the exudates, which persisted for more than 72 h. The pharmacokinetic (PK) profiles of NAI-603 and ramoplanin at 20 mg/kg show similar half-lives (3.27 and 3.80 h, respectively) with the maximum concentration (Cmax) markedly higher for NAI-603 (207 µg/ml versus 79 µg/ml). The favorable pharmacological profile of NAI-603, coupled with the absence of local tolerability issues, supports further investigation.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Depsipeptídeos/química , Acetamidas/farmacologia , Acetamidas/uso terapêutico , Animais , Antibacterianos/química , Enterococcus/efeitos dos fármacos , Feminino , Linezolida , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Oxazolidinonas/farmacologia , Oxazolidinonas/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Teicoplanina/farmacologia , Teicoplanina/uso terapêutico , Vancomicina/farmacologia , Vancomicina/uso terapêutico
12.
Mar Biotechnol (NY) ; 24(1): 255-262, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34855031

RESUMO

Cobia (Rachycentron canadum) is a marine teleost species with great productive potential worldwide. However, the genomic information currently available for this species in public databases is limited. Such lack of information hinders gene expression assessments that might bring forward novel insights into the physiology, ecology, evolution, and genetics of this potential aquaculture species. In this study, we report the first de novo transcriptome assembly of R. canadum liver, improving the availability of novel gene sequences for this species. Illumina sequencing of liver transcripts generated 1,761,965,794 raw reads, which were filtered into 1,652,319,304 high-quality reads. De novo assembly resulted in 101,789 unigenes and 163,096 isoforms, with an average length of 950.61 and 1,617.34 nt, respectively. Moreover, we found that 126,013 of these transcripts bear potentially coding sequences, and 125,993 of these elements (77.3%) correspond to functionally annotated genes found in six different databases. We also identified 701 putative ncRNA and 35,414 putative lncRNA. Interestingly, homologues for 410 of these putative lncRNAs have already been observed in previous analyses with Danio rerio, Lates calcarifer, Seriola lalandi dorsalis, Seriola dumerili, or Echeneis naucrates. Finally, we identified 7894 microsatellites related to cobia's putative lncRNAs. Thus, the information derived from the transcriptome assembly described herein will likely assist future nutrigenomics and breeding programs involving this important fish farming species.


Assuntos
Perciformes , Transcriptoma , Animais , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Anotação de Sequência Molecular , Perciformes/genética
13.
Antimicrob Agents Chemother ; 55(4): 1671-6, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21220527

RESUMO

NAI-107 is a novel lantibiotic active against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), glycopeptide-intermediate S. aureus (GISA), and vancomycin-resistant enterococci (VRE). The aim of this study was to evaluate the in vivo efficacy of NAI-107 in animal models of severe infection. In acute lethal infections induced with a penicillin-intermediate Streptococcus pneumoniae strain in immunocompetent mice, or with MRSA, GISA, and VRE strains in neutropenic mice, the 50% effective dose (ED(50)) values of NAI-107 were comparable or lower than those of reference compounds, irrespective of the strain and immune status (0.51 to 14.2 mg/kg of body weight for intravenous [i.v.] NAI-107, 5.1 to 22.4 for oral linezolid, and 22.4 for subcutaneous [s.c.] vancomycin). In the granuloma pouch model induced in rats with a MRSA strain, intravenous NAI-107 showed a dose-proportional bactericidal activity that, at a single 40-mg/kg dose, compared with 2 20-mg/kg doses at a 12-h or 24-h interval, caused a 3-log(10)-CFU/ml reduction of viable MRSA in exudates that persisted for more than 72 h. Rat endocarditis was induced with a MRSA strain and treated for five consecutive days. In a first experiment, using 5, 10, or 20 mg/kg/day, and in a second experiment, when 10 mg/kg at 12-h intervals was compared to 20 mg/kg/day, intravenous NAI-107 was effective in reducing the bacterial load in heart vegetations in a dose-proportional manner. Trough plasma levels, as determined on days 2 and 5, were several times higher than the NAI-107 minimal bactericidal concentration (MBC). NAI-107 binding to rat and human serum ranges between 93% and 98.6%. The rapid bactericidal activity of NAI-107 observed in vitro was thus confirmed by the efficacy in several models of experimental infection induced by Gram-positive pathogens, supporting further investigation of the compound.


Assuntos
Antibacterianos/uso terapêutico , Bacteriocinas/uso terapêutico , Animais , Farmacorresistência Bacteriana Múltipla , Endocardite/tratamento farmacológico , Feminino , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Ratos , Ratos Sprague-Dawley , Infecções Estafilocócicas/tratamento farmacológico , Resistência a Vancomicina
15.
Appl Microbiol Biotechnol ; 88(6): 1261-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20865256

RESUMO

Microbial pathogens are becoming increasingly resistant to available treatments, and new antibiotics are badly needed, but the pipeline of compounds under development is scarce. Furthermore, the majority of antibiotics under development are improved derivatives of marketed compounds, which are at best only partially effective against prevailing resistance mechanisms. In contrast, antibiotics endowed with new mechanisms of action are expected to be highly effective against multi-drug resistant pathogens. In this review, examples are provided of new antibiotics classes in late discovery or clinical development, arising from three different avenues: (1) compounds discovered and never brought to market by large pharmaceutical companies; (2) old compounds reanalyzed and rejuvinated with today's tools; and (3) newly discovered molecules. For each compound, we will briefly describe original discovery, mechanism of action, any known resistance, antimicrobial profile, and current status of development.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Descoberta de Drogas/métodos , Descoberta de Drogas/tendências , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Humanos
16.
J Fungi (Basel) ; 6(3)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971732

RESUMO

Commensal yeast from the genus Candida is part of the healthy human microbiota. In some cases, Candida spp. dysbiosis can result in candidiasis, the symptoms of which may vary from mild localized rashes to severe disseminated infections. The most prevalent treatments against candidiasis involve fluconazole, itraconazole, miconazole, and caspofungin. Moreover, amphotericin B associated with prolonged azole administration is utilized to control severe cases. Currently, numerous guidelines recommend echinocandins to treat invasive candidiasis. However, resistance to these antifungal drugs has increased dramatically over recent years. Considering this situation, new therapeutic alternatives should be studied to control candidiasis, which has become a major medical concern. Limonene belongs to the group of terpene molecules, known for their pharmacological properties. In this study, we evaluated in vitro the limonene concentration capable of inhibiting the growth of yeast from the genus Candida susceptible or resistant to antifungal drugs and its capacity to induce fungal damage. In addition, intravaginal fungal infection assays using a murine model infected by Candida albicans were carried out and the fungal burden, histopathology, and scanning electron microscopy were evaluated. All of our results suggest that limonene may play a protective role against the infection process by yeast from the genus Candida.

17.
J Fungi (Basel) ; 6(4)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33322197

RESUMO

Cachexia (CC) is a devastating metabolic syndrome associated with a series of underlying diseases that greatly affects life quality and expectancy among cancer patients. Studies involving mouse models, in which CC was induced through inoculation with tumor cells, originally suggested the existence of a direct correlation between the development of this syndrome and changes in the relative proportions of several bacterial groups present in the digestive tract. However, these analyses have focus solely on the characterization of bacterial dysbiosis, ignoring the possible existence of changes in the relative populations of fungi, during the development of CC. Thus, the present study sought to expand such analyses, by characterizing changes that occur in the gut fungal population (mycobiota) of mice, during the development of cancer-induced cachexia. Our results confirm that cachectic animals, submitted to Lewis lung carcinoma (LLC) transplantation, display significant differences in their gut mycobiota, when compared to healthy controls. Moreover, identification of dysbiotic fungi showed remarkable consistency across successive levels of taxonomic hierarchy. Many of these fungi have also been associated with dysbioses observed in a series of gut inflammatory diseases, such as obesity, colorectal cancer (CRC), myalgic encephalomyelitis (ME) and inflammatory bowel disease (IBD). Nonetheless, the dysbiosis verified in the LLC model of cancer cachexia seems to be unique, presenting features observed in both obesity (reduced proportion of Mucoromycota) and CRC/ME/IBD (increased proportions of Sordariomycetes, Saccharomycetaceae and Malassezia). One species of Mucoromycota (Rhyzopus oryzae) stands out as a promising probiotic candidate in adjuvant therapies, aimed at treating and/or preventing the development of CC.

18.
Gigascience ; 8(4)2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31222200

RESUMO

BACKGROUND: The Docker project is providing a promising strategy for the development of virtualization systems in bioinformatics. However, implementation, management, and launching of Docker containers is not entirely trivial for users not fully familiarized with command line interfaces. This has prompted the development of graphical user interfaces to facilitate the interaction of inexperienced users with Docker environments. RESULTS: We describe the BioPortainer Workbench, an integrated Docker system that assists inexperienced users in interacting with a bioinformatics-dedicated Docker environment at 3 main levels: (i) infrastructure, (ii) platform, and (iii) application. CONCLUSIONS: The BioPortainer Workbench represents a pioneering effort in developing a comprehensive and easy-to-use Docker platform focused on bioinformatics, which may greatly assist in the dissemination of Docker virtualization technology in this complex field of research.


Assuntos
Biologia Computacional , Software , Biologia Computacional/métodos , Interface Usuário-Computador , Fluxo de Trabalho
19.
PLoS Negl Trop Dis ; 13(7): e0007576, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31306428

RESUMO

BACKGROUND: The genus Paracoccidioides consists of thermodymorphic fungi responsible for Paracoccidioidomycosis (PCM), a systemic mycosis that has been registered to affect ~10 million people in Latin America. Biogeographical data subdivided the genus Paracoccidioides in five divergent subgroups, which have been recently classified as different species. Genomic sequencing of five Paracoccidioides isolates, representing each of these subgroups/species provided an important framework for the development of post-genomic studies with these fungi. However, functional annotations of these genomes have not been submitted to manual curation and, as a result, ~60-90% of the Paracoccidioides protein-coding genes (depending on isolate/annotation) are currently described as responsible for hypothetical proteins, without any further functional/structural description. PRINCIPAL FINDINGS: The present work reviews the functional assignment of Paracoccidioides genes, reducing the number of hypothetical proteins to ~25-28%. These results were compiled in a relational database called ParaDB, dedicated to the main representatives of Paracoccidioides spp. ParaDB can be accessed through a friendly graphical interface, which offers search tools based on keywords or protein/DNA sequences. All data contained in ParaDB can be partially or completely downloaded through spreadsheet, multi-fasta and GFF3-formatted files, which can be subsequently used in a variety of downstream functional analyses. Moreover, the entire ParaDB environment has been configured in a Docker service, which has been submitted to the GitHub repository, ensuring long-term data availability to researchers. This service can be downloaded and used to perform fully functional local installations of the database in alternative computing ecosystems, allowing users to conduct their data mining and analyses in a personal and stable working environment. CONCLUSIONS: These new annotations greatly reduce the number of genes identified solely as hypothetical proteins and are integrated into a dedicated database, providing resources to assist researchers in this field to conduct post-genomic studies with this group of human pathogenic fungi.


Assuntos
Bases de Dados Genéticas , Genoma Fúngico/genética , Anotação de Sequência Molecular , Paracoccidioides/genética , Paracoccidioidomicose/microbiologia , Sequência de Aminoácidos , Sequência de Bases , Computadores Moleculares , Ecossistema , Proteínas Fúngicas/genética , Humanos , América Latina , Paracoccidioides/isolamento & purificação , Pesquisa
20.
J Med Chem ; 50(13): 3077-85, 2007 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-17542573

RESUMO

Ramoplanin is a glycolipodepsipeptide antibiotic active against Gram-positive bacteria including vancomycin-resistant enterococci. Ramoplanin inhibits bacterial cell wall biosynthesis by a mechanism different from that of glycopeptides and hence does not show cross-resistance with these antibiotics. The systemic use of ramoplanin has been so far prevented because of its low local tolerability when injected intravenously. To overcome this problem, the fatty acid side chain of ramoplanin was selectively removed and replaced with a variety of different carboxylic acids. Many of the new ramoplanin derivatives showed antimicrobial activity similar to that of the natural precursor coupled with a significantly improved local tolerability. Among them the derivative in which the 2-methylphenylacetic acid has replaced the di-unsaturated fatty acid side chain (48) was selected as the most interesting compound and submitted to further in vitro and in vivo characterization studies.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Depsipeptídeos/síntese química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Hemólise , Testes de Sensibilidade Microbiana , Ratos , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo , Streptococcus pyogenes/efeitos dos fármacos , Relação Estrutura-Atividade
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