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1.
Infect Ecol Epidemiol ; 11(1): 1975530, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531964

RESUMO

Salmonellosis is a global health problem, affecting approximately 1.3 billion people annually. Most of these cases are related to food contamination. However, although the majority of Salmonella serovars are pathogenic to humans, animals can be asymptomatic carriers of these bacteria. Nowadays, a wide range of animals is present in human households as pets, including reptiles, amphibians, dogs, cats, ornamental birds, and rodents. Pets contaminate the environment of their owners by shedding the bacteria intermittently in their feaces. In consequence, theyare thought to cause salmonellosis through pet-to-human transmission. Each Salmonella serovar has a different zoonotic potential, which is strongly regulated by stress factors such as transportation, crowding, food deprivation, or temperature. In this review, we summarize the latest reports concerning Salmonella-prevalence and distribution in pets as well as the risk factors and means of prevention of human salmonellosis caused by contact with their pets. Our literature analysis (based on PubMed and Google Scholar databases) is limited to the distribution of Salmonella serovars found in commonly owned pet species. We collected the recent results of studies concerning testing for Salmonella spp. in biological samples, indicating their prevalence in pets, with regard to clinical cases of human salmonellosis.

2.
Viruses ; 13(6)2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208484

RESUMO

Pets play a crucial role in the development of human feelings, social life, and care. However, in the era of the prevailing global pandemic of COVID-19 disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), many questions addressing the routes of the virus spread and transmission to humans are dramatically emerging. Although cases of SARS-CoV-2 infection have been found in pets including dogs, cats, and ferrets, to date there is no strong evidence for pet-to-human transmission or sustained pet-to-pet transmission of SARS-CoV-2. However, an increasing number of studies reporting detection of SARS-CoV-2 in farmed minks raises suspicion of potential viral transmission from these animals to humans. Furthermore, due to the high susceptibility of cats, ferrets, minks and hamsters to COVID-19 infection under natural and/or experimental conditions, these animals have been extensively explored as animal models to study the SARS-CoV-2 pathogenesis and transmission. In this review, we present the latest reports focusing on SARS-CoV-2 detection, isolation, and characterization in pets. Moreover, based on the current literature, we document studies aiming to broaden the knowledge about pathogenicity and transmissibility of SARS-CoV-2, and the development of viral therapeutics, drugs and vaccines. Lastly, considering the high rate of SARS-CoV-2 evolution and replication, we also suggest routes of protection against the virus.


Assuntos
COVID-19/transmissão , Animais de Estimação/virologia , SARS-CoV-2/patogenicidade , Zoonoses/transmissão , Zoonoses/virologia , Animais , COVID-19/prevenção & controle , Gatos/virologia , Cães/virologia , Fazendas , Furões/virologia , Humanos , Vison/virologia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
3.
Sci Rep ; 11(1): 8896, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33903615

RESUMO

Our research aims to expand the knowledge on relationships between the structure of cationic dicephalic surfactants-N,N-bis[3,3_-(dimethylamine)propyl]alkylamide dihydrochlorides and N,N-bis[3,3_-(trimethylammonio)propyl]alkylamide dibromides (alkyl: n-C9H19, n-C11H23, n-C13H27, n-C15H31)-and their antifungal mechanism of action on Candida albicans. The mentioned groups of amphiphilic substances are characterized by the presence of a weak, hydrochloride cationic center readily undergoing deprotonation, as well as a stable, strong quaternary ammonium group and alkyl chains capable of strong interactions with fungal cells. Strong fungicidal properties and the role in creation and eradication of biofilm of those compounds were discussed in our earlier works, yet their mechanism of action remained unclear. It was shown that investigated surfactants induce strong oxidative stress and cause increase in cell membrane permeability without compromising its continuity, as indicated by increased potassium ion (K+) leakage. Thus experiments carried out on the investigated opportunistic pathogen indicate that the mechanism of action of the researched surfactants is different than in the case of the majority of known surfactants. Results presented in this paper significantly broaden the understanding on multifunctional cationic surfactants and their mechanism of action, as well as suggest their possible future applications as surface coating antiadhesives, fungicides and antibiofilm agents in medicine or industry.


Assuntos
Antifúngicos , Biofilmes/efeitos dos fármacos , Candida albicans/fisiologia , Tensoativos , Antifúngicos/química , Antifúngicos/farmacologia , Biofilmes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Tensoativos/química , Tensoativos/farmacologia
4.
Int J Mol Sci ; 22(5)2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33800082

RESUMO

Helicobacter pylori, a gastric pathogen associated with a broad range of stomach diseases, has a high tendency to become resistant to antibiotics. One of the most important factors related to therapeutic failures is its ability to change from a spiral to a coccoid form. Therefore, the main aim of our original article was to determine the influence of myricetin, a natural compound with an antivirulence action, on the morphological transformation of H. pylori and check the potential of myricetin to increase the activity of antibiotics against this pathogen. We observed that sub-minimal inhibitory concentrations (sub-MICs) of this compound have the ability to slow down the process of transformation into coccoid forms and reduce biofilm formation of this bacterium. Using checkerboard assays, we noticed that the exposure of H. pylori to sub-MICs of myricetin enabled a 4-16-fold reduction in MICs of all classically used antibiotics (amoxicillin, clarithromycin, tetracycline, metronidazole, and levofloxacin). Additionally, RT-qPCR studies of genes related to the H. pylori morphogenesis showed a decrease in their expression during exposure to myricetin. This inhibitory effect was more strongly seen for genes involved in the muropeptide monomers shortening (csd3, csd6, csd4, and amiA), suggesting their significant participation in the spiral-to-coccoid transition. To our knowledge, this is the first research showing the ability of any compound to synergistically interact with all five antibiotics against H. pylori and the first one showing the capacity of a natural substance to interfere with the morphological transition of H. pylori from spiral to coccoid forms.


Assuntos
Antibacterianos/farmacologia , Flavonoides/farmacologia , Helicobacter pylori/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Helicobacter pylori/patogenicidade , Helicobacter pylori/fisiologia , Testes de Sensibilidade Microbiana
5.
Pathogens ; 9(12)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353223

RESUMO

Helicobacter pylori is a bacterium that is capable of colonizing a host for many years, often for a lifetime. The survival in the gastric environment is enabled by the production of numerous virulence factors conditioning adhesion to the mucosa surface, acquisition of nutrients, and neutralization of the immune system activity. It is increasingly recognized, however, that the adaptive mechanisms of H. pylori in the stomach may also be linked to the ability of this pathogen to form biofilms. Initially, biofilms produced by H. pylori were strongly associated by scientists with water distribution systems and considered as a survival mechanism outside the host and a source of fecal-oral infections. In the course of the last 20 years, however, this trend has changed and now the most attention is focused on the biomedical aspect of this structure and its potential contribution to the therapeutic difficulties of H. pylori. Taking into account this fact, the aim of the current review is to discuss the phenomenon of H. pylori biofilm formation and present this mechanism as a resultant of the virulence and adaptive responses of H. pylori, including morphological transformation, membrane vesicles secretion, matrix production, efflux pump activity, and intermicrobial communication. These mechanisms will be considered in the context of transcriptomic and proteomic changes in H. pylori biofilms and their modulating effect on the development of this complex structure.

6.
ACS Omega ; 5(38): 24546-24557, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33015472

RESUMO

New polymer-inorganic composites with antibiofilm features based on the granulated poly(tetrafluoroethylene) (PTFE) and apatite materials were obtained using a standard hydraulic press. The study was performed in hydroxy- and fluorapatites doped with different amounts of silver ions and followed by heat treatment at 600 °C. The structural, morphological, and physicochemical properties were determined by X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy-energy-dispersive spectrometry (SEM-EDS), and transition electron microscopy (TEM). The antibacterial properties of the obtained materials were evaluated against Gram-negative pathogens such as Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli as well as against Gram-positive bacteria Staphylococcus epidermidis. The cytotoxicity assessment was carried out on the red blood cells (RBC) as a cell model for in vitro study. Moreover, the biofilm formation on the biocomposite surface was studied using confocal laser scanning microscopy (CLSM).

7.
Antibiotics (Basel) ; 9(10)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007899

RESUMO

Helicobacter pylori is a Gram-negative bacterium responsible for the development of gastric diseases. The issue of spreading antibiotic resistance of H. pylori and its limited therapeutic options is an important topic in modern gastroenterology. This phenomenon is greatly associated with a very narrow range of antibiotics used in standard therapies and, as a consequence, an alarmingly high detection of multidrug-resistant H. pylori strains. For this reason, scientists are increasingly focused on the search for new substances that will not only exhibit antibacterial effect against H. pylori, but also potentiate the activity of antibiotics. The aim of the current review is to present scientific reports showing newly discovered or repurposed compounds with an ability to enhance the antimicrobial activity of classically used antibiotics against H. pylori. To gain a broader context in their future application in therapies of H. pylori infections, their antimicrobial properties, such as minimal inhibitory concentrations and minimal bactericidal concentrations, dose- and time-dependent mode of action, and, if characterized, anti-biofilm and/or in vivo activity are further described. The authors of this review hope that this article will encourage the scientific community to expand research on the important issue of synergistic therapies in the context of combating H. pylori infections.

8.
Biomed Pharmacother ; 129: 110435, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32593967

RESUMO

In this study, we evaluated antimicrobial activity, antimicrobial activity in combination with antibiotics, and chemical composition of Nepalese propolis 70% ethanolic extracts. Propolis originated from two genera of bees - Apis mellifera L. and Trigona sp. HPLC-DAD-MS/MS analyses revealed that the composition of both extracts was almost the same and the main components were flavonoid aglycones (mainly neoflavonoids, isoflavonoids) and pterocarpans. The highest antibacterial activity (disc diffusion test) was observed against Helicobacter pylori, Staphylococcus aureus and Shigella flexneri. Antibiotics exhibited synergism with Apis mellifera L. and Trigona sp. propolis against S. aureus and the strongest effect was observed for the combination with amikacin and tetracycline. Moreover, Nepalase propolis inhibited filamentation of C. albicans and caused oxidative stress by production of the superoxide anion radical (O2-) and a lower concentration of the hydroxyl radical (OH). Propolis extracts are potent antibacterial agents and may be used in combination with antibiotics.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Abelhas , Candida albicans/efeitos dos fármacos , Helicobacter pylori/efeitos dos fármacos , Própole/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Sinergismo Farmacológico , Helicobacter pylori/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Nepal , Estresse Oxidativo/efeitos dos fármacos , Própole/química , Staphylococcus aureus/crescimento & desenvolvimento
9.
Appl Microbiol Biotechnol ; 103(2): 625-632, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30460534

RESUMO

Quaternary ammonium salts (QAS), as the surface active compounds, are widely used in medicine and industry. Their common application is responsible for the development of microbial resistance to QAS. To overcome, this issue novel surfactants, including gemini-type ones, were developed. These unique compounds are built of two hydrophilic and two hydrophobic parts. The double-head double-tail type of structure enhances their physicochemical properties (like surface activity) and biological activity and makes them a potential candidate for new drugs and disinfectants. Antimicrobial activity is mainly attributed to the biocidal action towards bacteria and fungi in their planktonic and biofilm forms, but the mode of action of gemini QAS is not yet fully understood. Moreover, gemini surfactants are of particular interest towards their application as gene carriers. Cationic charge of gemini QAS and their ability to form liposomes facilitate DNA compaction and transfection of the target cells. Multifunctional nature of gemini QAS is the reason of the long-standing research on mainly their structure-activity relationship.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Sais/farmacologia , Membrana Celular/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/química , Sais/síntese química , Sais/química , Transfecção
10.
Curr Microbiol ; 72(5): 570-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26804795

RESUMO

In diagnostic microbiology as well as in microbiological research, the identification of a microorganism is a crucial and decisive stage. A broad choice of methods is available, based on both phenotypic and molecular properties of microbes. The aim of this study was to compare the application of phenotypic and molecular tools in bacterial identification on the example of Gram-negative intestine rod with an ambiguous phenotype. Different methods of identification procedure, which based on various properties of bacteria, were applied, e.g., microscopic observation of single-bacterial cells, macroscopic observation of bacterial colonies morphology, the automated system of microorganism identification (biochemical tests), the mass spectrometry method (analysis of bacterial proteome), and genetic analysis with PCR reactions. The obtained results revealed discrepancies in the identification of the tested bacterial strain with an atypical phenotype: mucous morphology of colonies, not characteristic for either E. coli and Citrobacter spp., mass spectrometry analysis of proteome initially assigned the tested strain to Citrobacter genus (C. freundii) and biochemical profiles pointed to Escherichia coli. A decisive method in the current study was genetic analysis with PCR reactions which identified conserved genetic sequences highly specific to E. coli species in the genome of the tested strain.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/microbiologia , Reação em Cadeia da Polimerase/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Técnicas de Tipagem Bacteriana/instrumentação , Fezes/microbiologia , Bactérias Gram-Negativas/química , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/diagnóstico , Humanos , Fenótipo
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