DSpace Coleção:http://repositorio.ufc.br/handle/riufc/4032024-03-28T22:25:16Z2024-03-28T22:25:16ZEfeito da prometazina impregnada em cateter vesical de demora sobre biofilmes de bacilos Gram negativos associados à infecção do trato urinárioGomes, Francisco Ivanilsom Firmianohttp://repositorio.ufc.br/handle/riufc/763982024-03-06T13:30:41Z2023-01-01T00:00:00ZTítulo: Efeito da prometazina impregnada em cateter vesical de demora sobre biofilmes de bacilos Gram negativos associados à infecção do trato urinário
Autor(es): Gomes, Francisco Ivanilsom Firmiano
Abstract: Urinary tract infection is one of the main complications related to health care, especially when
it comes to the use of invasive medical devices. Indwelling bladder catheters are foreign
bodies that are inserted into the urethra and made tolerant to bacterial colonization and
biofilm development. Biofilms provide greater protection and bacterial resistance. Efflux
pumps are important means of bacterial evasion of the action of antimicrobials and participate
in the processes of formation and maintenance of bacterial biofilms, and can therefore be used
to prevent the formation of bacterial biofilms. Thus, this study aimed to evaluate the
inhibitory effect of a promethazine efflux pump impregnated in a catheter on the formation of
biofilms by Gram-negative bacilli associated with urinary tract infection. 23 (5 Escherichia
coli, 6 Klebsiella pneumoniae, 6 Proteus mirabilis and 6 Pseudomonas aeruginosa) isolates of
Gram negative bacilli were used. The sensitivity of the isolates to promethazine was evaluated
in planktonic and biofilm forms. The effect of the drug was evaluated in the concentrations
referring to the minimum inhibitory concentration MIC, MIC/2 and MIC/4 on the formation
of biofilms and in the concentrations referring to 2x minimum elimination concentration on
the biofilm CEMB, CEMB and CEMB/2 on mature biofilms , using the biomass
quantification technique. Furthermore, Foley catheter fragments were impregnated with
promethazine 390 μg/mL and 3900 μg/mL to evaluate the effect of the drug on the formation
of biofilms on the surface of the catheters, by counting colony forming units (CFU).
Promethazine MICs ranged from 97.6 to 781.25 μg/mL and CEMBs ranged from 390.6 to
3125 μg/mL. Promethazine reduced (P<0.05) the biomass of biofilms in formation, in all
concentrations tested, by 37.3%, 41.5% and 58.7%, from the lowest to the highest
concentration. The impregnation of the catheters with promethazine at 390 μg/mL, in general,
did not obtain significant results, however for the species of Escherichia coli and Proteus
mirabilis the reduction in CFU's was 3 log. The impregnation of the catheters with 3900
μg/mL of promethazine significantly reduced the CFU's of the studied species, presenting
significant results for all of them and, in general, the reduction of CFU's was greater than 5
log when compared to the control. When combined with antimicrobials, promethazine did not
show a synergistic effect with antibiotics.
Tipo: Dissertação2023-01-01T00:00:00ZEfeito in vitro do ácido tânico sobre células planctônicas e biofilmes de Candida ssp. e seu mecanismo de açãoMoreira, Lara Elloyse Almeidahttp://repositorio.ufc.br/handle/riufc/763752024-03-04T17:48:26Z2024-01-01T00:00:00ZTítulo: Efeito in vitro do ácido tânico sobre células planctônicas e biofilmes de Candida ssp. e seu mecanismo de ação
Autor(es): Moreira, Lara Elloyse Almeida
Abstract: Fungal infections are an emerging public health problem, particularly in nosocomial settings
and in immunosuppressed patients. Candida spp. is characterized as an important opportunistic
genus that, over the years, presents more and more strains resistant to the antifungal treatments
used. With increasing clinical resistance, a change in the epidemiology of Candida infections
is observed, which highlights the need for new therapeutic strategies. In this context, products
of natural origin stand out for presenting reports in the literature about their in vitro antifungal
activity, in which tannins are an important class of emphasis. In this context, tannic acid is a
hydrolyzable tannin that has several biological properties already demonstrated in vitro, such
as antioxidant and anticancer, as well as antimicrobial against viruses, parasites and bacteria.
However, there are few reports in the literature about its antifungal properties against Candida
spp. Therefore, the present study aimed to evaluate the in vitro antifungal activity of tannic acid,
isolated and associated with antifungals commonly used in therapy, as well as evaluating its
cytotoxicity, its antibiofilm property and elucidating its mechanism of action against Candida.
spp. sensitive and resistant to fluconazole. The broth microdilution technique was used to
determine the Minimum Inhibitory Concentration (MIC) and the checkerboard technique was
used to determine the pharmacological interaction between tannic acid and antifungals. The
evaluation of cytotoxicity was evaluated in L929 murine fibroblast cells and its hemolytic effect
on mouse red blood cells. Its mechanism of action was evaluated by flow cytometry assays and
its antibiofilm effect was evaluated in 96-well plates. Tannic acid showed MICs ranging from
0.06 to 0.5 μg/ml. Pharmacological interaction tests demonstrated that 100% of interactions
were indifferent in the combination of tannic acid + amphotericin B; 93.75% of the interactions
were indifferent and one strain showed an antagonistic interaction in the combination of tannic
acid + itraconazole and the combination of tannic acid + fluconazole showed 75% of indifferent
interactions, 12.5% synergistic and 12.5% additive. Tannic acid did not present cytotoxic and
hemolytic effects at the concentrations at which it exerts its antifungal activity. Furthermore, it
is indicated that its mechanism of action is exerted through pro-oxidant activity, with the
production of reactive oxygen species in fungal cells, which generate oxidative stress, resulting
in the induction of signals that mediate apoptosis. Its antibiofilm activity occurs in higher
concentrations, inhibiting around 50% of the biofilm at concentrations of 128x MIC. Therefore,
tannic acid has potential antifungal activity against strains sensitive and resistant to fluconazole
at safe concentrations, both in planktonic cells and in biofilm. However, more studies are
needed to promote such applications in vivo.
Tipo: Dissertação2024-01-01T00:00:00ZEfeito do haloperidol sobre o biofilme e sensibilidade
antimicrobiana de bacilos gram negativos de infecções relacionadas à saúdeSouza, Paulo Roberto Honóriohttp://repositorio.ufc.br/handle/riufc/763292024-03-08T12:22:38Z2023-01-01T00:00:00ZTítulo: Efeito do haloperidol sobre o biofilme e sensibilidade
antimicrobiana de bacilos gram negativos de infecções relacionadas à saúde
Autor(es): Souza, Paulo Roberto Honório
Abstract: Healthcare-related infections caused by Gram-negative bacteria have become a growing
problem with the increase of antimicrobial resistance, mainly mediated by biofilm production.
For this reason, it is necessary to search for new compounds and drugs that can help in the
treatment against these infections. Thus, the present study evaluated the effect of the
antipsychotic haloperidol on antimicrobial and antibiofilm sensitivity in Pseudomonas
aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae. Planktonic sensitivity
testing to haloperidol alone and in combination with antimicrobials was done by the broth
microdilution method to determine the (MIC). The antibiofilm effect was evaluated by
quantification of biofilm biomass, stained with crystal violet, and metabolic activity, using
resazurin, to determine the minimal biofilm elimination concentration (MBEC). Furthermore,
the structure of the biofilm after exposure to haloperiodol was evaluated by confocal
microscopy. The minimum inhibitory concentration (MIC) ranges of haloperiodol were 512,
64 to 128 and 128 µg /mL for P. aeruginosa, A. baumannii and K. pneumoniae respectively.
In combination, there was a reduction MICs of the antimicrobials in the combination of
haloperidol MIC/2 with amikacin. In relation to biofilm, haloperidol caused destructuring of
the biomass in all species, in concentrations of 512, 256 and 128 µg /mL the reductions were
73%, 77% and 77% in P. aeruginosa, 78%, 76% and 65% in A. baumannii and 85%, 66% and
51% in K. pneumoniae respectively. The MBECs of the antimicrobials after associating
(MBEC/2) were reduced with statistical significance against P. aeruginosa, and the MBEC of
meropenem was reduced in all species. In summary, haloperidol inhibits bacterial growth
besides dispersing and destructuring the biofilm, and may potentiate the effect of
antimicrobials.
Tipo: Dissertação2023-01-01T00:00:00ZAtividade da prometazina, deferiprona e mel de Manuka contra biofilmes de Staphylococcus aureus e Pseudomonas aeruginosa em modelo ex vivo de feridasFreitas, Alyne Soareshttp://repositorio.ufc.br/handle/riufc/762782024-02-27T10:30:02Z2022-01-01T00:00:00ZTítulo: Atividade da prometazina, deferiprona e mel de Manuka contra biofilmes de Staphylococcus aureus e Pseudomonas aeruginosa em modelo ex vivo de feridas
Autor(es): Freitas, Alyne Soares
Abstract: Infection is the most common factor that leads to wound chronicity and complication, especially when microorganisms are in the form of biofilm. Thus, this study aimed to evaluate the antibiofilm activity of promethazine, deferiprone and Manuka honey against Staphylococcus aureus and Pseudomonas aeruginosa in vitro and ex vivo in a wound model on porcine skin. For this, the Minimum Inhibitory Concentrations (MICs) for promethazine, deferiprone and Manuka honey were determined against eight isolates of each bacterial species. Then, the effect of these compounds on mature biofilms was evaluated to define the Minimum Biofilm Eradication Concentration (MBEC) and quantify the biomass of the biofilms. Finally, biofilms were formed on porcine skin and the effect of the compounds was evaluated by counting Colony-Forming Units (CFUs) and analyzing the architecture of biofilms by confocal microscopy. Promethazine, deferiprone and Manuka honey MICs ranged from 97.66 to 781.25 μg/mL, 512 to >1024 μg/mL and 10 to 40%, respectively, against both bacterial species. The minimum biofilm eradication concentrations (MBEC) values for promethazine, deferiprone and Manuka honey were 195.31-1562.5 μg/mL, ≥1024 μg/mL and from 20->40%, respectively, for the two species. As for the quantification of mature biofilm biomass, promethazine caused a significant reduction in concentrations of 781.25 and 195.31 μg/mL for S. aureus and 97.66 - 1562.5 μg/mL for P. aeruginosa. Deferiprone significantly reduced biomass at 512 and 1024 μg/mL concentrations for both species. While Manuka honey reduced the biomass only of S. aureus, at concentrations of 20 and 40%. Concerning biofilms grown on ex vivo model, the three tested compounds significantly reduced CFU counts for both bacterial species, altering the biofilm architecture. Promethazine was the most effective compound, reducing the CFU counts by about 4 log, in the MBEC concentration. Promethazine, deferiprone and Manuka honey have different in vitro antimicrobial properties, but were effective against biofilms grown on ex vivo wound model, showing their potential use in the management of biofilm-associated wounds.
Tipo: Dissertação2022-01-01T00:00:00Z