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1.
Exp Appl Acarol ; 85(1): 63-73, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34528136

RESUMO

Pathogens carried by ticks pose a threat to both human and animal health across the world. Typically associated with rural landscapes, ticks appear to adapt well to life in urban recreational areas. Although Dermacentor reticulatus is commonly found across Europe, data on the prevalence of pathogens in this tick species, in an urban environment, are very limited. PCR was used to examine 368 D. reticulatus individuals collected in the Zwierzyniecki Forest Nature Reserve in Bialystok, Poland. In total, 10.3% of ticks were infected, with Babesia spp. (9.2%), Anaplasma phagocytophilum (0.8%) and Borrelia burgdorferi sensu lato (0.3%). Rickettsia spp., Bartonella spp., and Coxiella burnetii were not detected. Sequence analysis for Babesia-positive samples identified 79.4% of them as Babesia canis, 8.8% as Babesia microti, 5.9% as Babesia spp., 2.9% as Babesia venatorum, and 2.9% as Babesia vogeli. Results obtained in this study indicate that D. reticulatus ticks found within the urban premises of the study area are infected with at least three pathogens and therefore are an important factor in public health risk for tick-borne diseases.


Assuntos
Anaplasma phagocytophilum , Babesia , Borrelia burgdorferi , Borrelia , Dermacentor , Animais , Polônia/epidemiologia
2.
J Antimicrob Chemother ; 75(5): 1146-1150, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31960042

RESUMO

BACKGROUND: The growing incidence of MDR Gram-negative bacteria is a rapidly emerging challenge in modern medicine. OBJECTIVES: We sought to establish the role of intrinsic drug-resistance regulators in combination with specific genetic mutations in 11 Enterobacter cloacae isolates obtained from a single patient within a 7 week period. METHODS: The molecular characterization of eight carbapenem-resistant and three carbapenem-susceptible E. cloacae ST89 isolates included expression-level analysis and WGS. Quantitative PCR included: (i) chromosomal cephalosporinase gene (ampC); (ii) membrane permeability factor genes, e.g. ompF, ompC, acrA, acrB and tolC; and (iii) intrinsic regulatory genes, e.g. ramA, ampR, rob, marA and soxS, which confer reductions in antibiotic susceptibility. RESULTS: In this study we describe the influence of the alterations in membrane permeability (ompF and ompC levels), intrinsic regulatory genes (ramA, marA, soxS) and intrinsic chromosomal cephalosporinase AmpC on reductions in carbapenem susceptibility of E. cloacae clinical isolates. Interestingly, only the first isolate possessed the acquired VIM-4 carbapenemase, which has been lost in subsequent isolates. The remaining XDR E. cloacae ST89 isolates presented complex carbapenem-resistance pathways, which included perturbations in permeability of bacterial membranes mediated by overexpression of ramA, encoding an AraC/XylS global regulator. Moreover, susceptible isolates differed significantly from other isolates in terms of marA down-regulation and soxS up-regulation. CONCLUSIONS: Molecular mechanisms of resistance among carbapenem-resistant E. cloacae included production of acquired VIM-4 carbapenemase, significant alterations in membrane permeability due to increased expression of ramA, encoding an AraC/XylS global regulator, and the overproduction of chromosomal AmpC cephalosporinase.


Assuntos
Citarabina , Enterobacter cloacae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Enterobacter cloacae/genética , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
3.
Molecules ; 23(10)2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30275354

RESUMO

The genus Bidens L. (Asteraceae) refers to several species of plants used in traditional phytotherapeutic preparations. B. tripartita, also known as bur marigold, is the most familiar plant and has been known as a remedy for chronic dysentery. The hydrodistilled essential oil of the aerial parts of the Polish B. tripartita was analyzed using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. To exclude any potential toxic effects of the oil on human dermal fibroblasts, the MTT test (methyl thiazolyl tetrazolium) and COMET assay (single-cell gel electrophoresis) were performed. Novel gel formulations as topical carriers for essential oil obtained from B. tripartita were developed and characterized. The bioadhesive properties of the designed preparations in the ex vivo model using the skin of hairless mice were also evaluated. The therapeutic efficacy of the topical formulations is influenced by active phytoconstituents and vehicle characteristics. The antifungal properties of the essential oil of B. tripartita were also tested against Candida species, and this oil appears to be a promising topical anticandidal agent.


Assuntos
Antifúngicos/química , Bidens/química , Candidíase/tratamento farmacológico , Óleos Voláteis/química , Extratos Vegetais/química , Óleos de Plantas/química , Administração Tópica , Animais , Antifúngicos/administração & dosagem , Candida/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogéis , Camundongos , Testes de Sensibilidade Microbiana , Óleos Voláteis/administração & dosagem , Extratos Vegetais/administração & dosagem , Óleos de Plantas/administração & dosagem , Pele/citologia
5.
Postepy Hig Med Dosw (Online) ; 71(0): 589-594, 2017 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-28791953

RESUMO

The effectiveness of carbapenems, considered as last-resort antimicrobials in severe infections, becomes compromised by bacterial resistance. The production of metallo-ß-lactamases (MBLs) is the most significant threat to carbapenems activity among Pseudomonas aeruginosa. The aim of this study was to assess the presence and type of MBLs genes in carbapenem-resistant P. aeruginosa clinical strains, to identify the location of MBLs genes and to determine genetic relatedness between MBL-producers using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The first identified MBL-positive (with blaVIM genes) P. aeruginosa strains were isolated from patients hospitalized in the University Clinical Hospital of Bialystok in the period from September 2012 to December 2013. Variants of MBLs genes and variable integron regions were characterized by PCR and sequencing. PFGE was performed after digesting of bacterial genomes by XbaI enzyme. By MLST seven housekeeping genes were analyzed for the determination of sequence type (ST). Three strains carried the blaVIM-2 gene and one harbored the blaVIM-4 gene. The blaVIM genes resided within class 1 integrons. PCR mapping of integrons revealed the presence of four different cassette arrays. Genetic relatedness analysis by PFGE classified VIM-positive strains into four unrelated pulsotypes (A-D). MLST demonstrated the presence of four (ST 111, ST27, and ST17) different sequence type including one previously undescribed new type of ST 2342. Antimicrobial susceptibility testing showed that VIM-positive strains were resistant to carbapenems, cephalosporins, aminoglycosides, and quinolones, intermediate to aztreonam, and susceptible only to colistin. Integrons mapping, PFGE, and MLST results may point to different origin of these strains and independent introduction into hospitalized patients.


Assuntos
Farmacorresistência Bacteriana , Infecções por Pseudomonas , Pseudomonas aeruginosa/classificação , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Campo Pulsado , Hospitais Universitários , Humanos , Integrons , Tipagem de Sequências Multilocus , Polônia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiologia , beta-Lactamases
6.
New Microbiol ; 38(2): 271-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25938753

RESUMO

The aim of the study was to evaluate the prevalence of OXA and other ß-lactamase genes, antibiotic susceptibility, and the genetic relatedness among clinical isolates of P. aeruginosa resistant to carbapenems. The presence of bla- OXA genes was demonstrated in 48% of isolates belonging to four PFGE profiles. Most of them contained the blaOXA-2 gene (88.3%). Other blaOXA genes (Ps1310 with blaOXA-30 and Ps1309 with blaOXA-10) were found in only two isolates. The tested isolates also contained other ß-lactamase genes such as blaVIM-2, blaVIM-4, blaSHV-5, and blaTEM-1. All isolates were susceptible only to colistin (100%).


Assuntos
Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , beta-Lactamases/genética , Hospitais Universitários , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/genética , Polônia , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , Resistência beta-Lactâmica
7.
J Virol ; 87(6): 3526-37, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23325679

RESUMO

We compared the relative efficacies against simian immunodeficiency virus (SIV) challenge of three vaccine regimens that elicited similar frequencies of SIV-specific CD4(+) and CD8(+) T-cell responses but differed in the level of antibody responses to the gp120 envelope protein. All macaques were primed with DNA plasmids expressing SIV gag, pol, env, and Retanef genes and were boosted with recombinant modified vaccinia Ankara virus (MVA) expressing the same genes, either once (1 × MVA) or twice (2 × MVA), or were boosted once with MVA followed by a single boost with replication-competent adenovirus (Ad) type 5 host range mutant (Ad5 h) expressing SIV gag and nef genes but not Retanef or env (1 × MVA/Ad5). While two of the vaccine regimens (1 × MVA and 1 × MVA/Ad5) protected from high levels of SIV replication only during the acute phase of infection, the 2 × MVA regimen, with the highest anti-SIV gp120 titers, protected during the acute phase and transiently during the chronic phase of infection. Mamu-A*01 macaques of this third group exhibited persistent Gag CD8(+)CM9(+) effector memory T cells with low expression of surface Programmed death-1 (PD-1) receptor and high levels of expression of genes associated with major histocompatibility complex class I (MHC-I) and MHC-II antigen. The fact that control of SIV replication was associated with both high titers of antibodies to the SIV envelope protein and durable effector SIV-specific CD8(+) T cells suggests the hypothesis that the presence of antibodies at the time of challenge may increase innate immune recruiting activity by enhancing antigen uptake and may result in improvement of the quality and potency of secondary SIV-specific CD8(+) T-cell responses.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Glicoproteínas de Membrana/imunologia , Receptor de Morte Celular Programada 1/imunologia , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Antivirais/sangue , Memória Imunológica , Macaca , Vacinas contra a SAIDS/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
8.
Scand J Infect Dis ; 46(4): 260-4, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24447252

RESUMO

BACKGROUND: The growing incidence of multidrug resistance (MDR) in bacteria is an emerging challenge in the treatment of infections. Acinetobacter baumannii is an opportunistic pathogen prone to exhibit MDR that contributes significantly to nosocomial infections, particularly in severely ill patients. Thus, we performed research on rifampicin activity against selected MDR OXA-72 carbapenemase-producing A. baumannii strains. Since it is widely accepted that rifampicin should not be used as monotherapy in order to avoid the rapid development of rifampicin resistance, we evaluated the efficacy of combination therapy with imipenem. METHODS: Minimal inhibitory concentrations (MICs) of both rifampicin and imipenem were determined by use of the broth microdilution method. Evaluations of the interactions between rifampicin and imipenem were performed by analysis of the fractional inhibitory concentration index (∑FIC), determined using the checkerboard titration method. RESULTS: All tested isolates showed full susceptibility to rifampicin. The checkerboard method revealed synergism in 5 isolates (29%) and an additive effect in another 5 isolates (29%); no difference was reported in the remaining 7 isolates (41%). Strains moderately resistant to imipenem (MIC ≤ 64 mg/l) tended to show synergy or additive interaction. CONCLUSIONS: We conclude that in vitro synergism or an additive interaction between rifampicin and imipenem most likely occurs in A. baumannii strains showing moderate resistance to imipenem (MIC ≤ 64 mg/l). Moreover, utilizing this combination in the therapy of infections caused by strains exhibiting higher levels of resistance (MIC > 64 mg/l) is not recommended since in this setting imipenem could not prevent the development of rifampicin resistance.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Imipenem/farmacologia , Rifampina/farmacologia , beta-Lactamases/genética , Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Proteínas de Bactérias/genética , Humanos , Testes de Sensibilidade Microbiana
9.
Int J Mol Sci ; 15(10): 17765-77, 2014 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-25272230

RESUMO

The combination of an antifungal agent and drug carrier with adjunctive antimicrobial properties represents novel strategy of complex therapy in pharmaceutical technology. The goal of this study was to investigate the unmodified and ion cross-linked chitosan's influence on anti-Candida activity of clotrimazole used as a model drug in hydrogels. It was particularly crucial to explore whether the chitosans' structure modification by ß-glycerophosphate altered its antifungal properties. Antifungal studies (performed by plate diffusion method according to CLSI reference protocol) revealed that hydrogels obtained with chitosan/ß-glycerophosphate displayed lower anti-Candida effect, probably as a result of weakened polycationic properties of chitosan in the presence of ion cross-linker. Designed chitosan hydrogels with clotrimazole were found to be more efficient against tested Candida strains and showed more favorable drug release profile compared to commercially available product. These observations indicate that novel chitosan formulations may be considered as promising semi-solid delivery system of clotrimazole.


Assuntos
Antifúngicos/química , Quitosana/química , Clotrimazol/química , Portadores de Fármacos/química , Glicerofosfatos/química , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Clotrimazol/farmacologia , Hidrogéis/química , Testes de Sensibilidade Microbiana
10.
Front Cell Infect Microbiol ; 14: 1289396, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655285

RESUMO

The global emergence of antimicrobial resistance to multiple antibiotics has recently become a significant concern. Gram-negative bacteria, known for their ability to acquire mobile genetic elements such as plasmids, represent one of the most hazardous microorganisms. This phenomenon poses a serious threat to public health. Notably, the significance of tigecycline, a member of the antibiotic group glycylcyclines and derivative of tetracyclines has increased. Tigecycline is one of the last-resort antimicrobial drugs used to treat complicated infections caused by multidrug-resistant (MDR) bacteria, extensively drug-resistant (XDR) bacteria or even pan-drug-resistant (PDR) bacteria. The primary mechanisms of tigecycline resistance include efflux pumps' overexpression, tet genes and outer membrane porins. Efflux pumps are crucial in conferring multi-drug resistance by expelling antibiotics (such as tigecycline by direct expelling) and decreasing their concentration to sub-toxic levels. This review discusses the problem of tigecycline resistance, and provides important information for understanding the existing molecular mechanisms of tigecycline resistance in Enterobacterales. The emergence and spread of pathogens resistant to last-resort therapeutic options stands as a major global healthcare concern, especially when microorganisms are already resistant to carbapenems and/or colistin.


Assuntos
Antibacterianos , Enterobacteriaceae , Tigeciclina , Tigeciclina/farmacologia , Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Humanos , Farmacorresistência Bacteriana Múltipla/genética , Farmacorresistência Bacteriana/genética , Minociclina/análogos & derivados , Minociclina/farmacologia , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia
11.
Mycoses ; 56(5): 576-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23565662

RESUMO

Significant changes in the frequency of candidaemia and the distribution of causative species have been noted worldwide in the last two decades. In this study, we present the results of the first multicentre survey of fungaemia in Polish hospitals. A total of 302 candidaemia episodes in 294 patients were identified in 20 hospitals during a 2-year period. The highest number of infections was found in intensive care (30.8%) and surgical (29.5%) units, followed by haematological (15.9%), 'others' (19.2%) and neonatological (4.6%) units. Candida albicans was isolated from 50.96% of episodes; its prevalence was higher in intensive care unit and neonatology (61.22% and 73.33%, respectively), and significantly lower in haematology (22%; P < 0.001). The frequency of C. krusei and C. tropicalis was significantly higher (24% and 18%) in haematology (P < 0.02); whereas, the distribution of C. glabrata (14.1%) and C. parapsilosis (13.1%) did not possess statistically significant differences between compared departments. Obtained data indicates that species distribution of Candida blood isolates in Polish hospitals reflects worldwide trends, particularly a decrease in the prevalence of infections due to C. albicans.


Assuntos
Candida/classificação , Candida/isolamento & purificação , Candidemia/epidemiologia , Candidemia/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Hospitais , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Polônia/epidemiologia , Prevalência , Estudos Retrospectivos , Adulto Jovem
12.
Molecules ; 18(7): 8607-17, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23881050

RESUMO

Erythromycin (EM) and tobramycin (TOB) are well-known and widely used antibiotics, belonging to different therapeutic groups: macrolide and aminoglycoside, respectively. Moreover, they possess different solubility: EM is slightly soluble and TOB is freely soluble in water. It was previously demonstrated that PAMAM dendrimers enhanced the pharmacological activity of antifungal drugs by increasing their solubility. Therefore, it appears interesting to investigate the effect of PAMAM-NH2 and PAMAM-OH dendrimers generation 2 (G2) and generation 3 (G3) on the antibacterial activity of antibiotics with different water solubility. In this study it was shown that the aqueous solubility of EM was significantly increased by PAMAM dendrimers (PAMAM-NH2 and PAMAM-OH caused about 8- and 7- fold solubility increases, respectively). However, it was indicated that despite the increase in the solubility, there was only slight influence on the antibacterial activity of EM (2- and 4-fold decreases in the MBC values of EM in the presence of PAMAM-OH G3 and PAMAM-NH2 G2 or G3 for strains of Staphylococcus aureus were noted, respectively). It was also found that there was no influence of PAMAM on the antibacterial activity of hydrophilic TOB.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Dendrímeros/química , Bactérias/isolamento & purificação , Eritromicina/química , Eritromicina/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Solubilidade , Tobramicina/química , Tobramicina/farmacologia
13.
Med Dosw Mikrobiol ; 65(1): 27-38, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24180129

RESUMO

INTRODUCTION: In recent years an alarming increase of carbapenem-resistant Enterobacteriaceae has been noticed, which creates frequent therapeutic problems, especially for patients residing in intensive care units (ICU). The aim of this study was to evaluate the prevalence of carbapenem-resistant strains of Enterobacteriaceae isolated in the years 2006-2011 at the University Hospital in Bialystok (UHB). METHODS: Based on microbiological analysis reports we conducted a retrospective study of strains resistant to carbapenems. We assigned strains to three carbapenem-resistance phenotypes, and analyzed susceptibility to antibiotics and prevalence of these strains in hospital wards and in clinical specimens collected from hospitalized patients. During a six-year period, 216 strains resistant to carbapenems were tested, which represents 0.96% of all Enterobacteriaceae (n = 22.391) isolated during this period. RESULTS: The greatest number of carbapenem-resistant strains was identified in 2011 (96 strains, 44.44%). Antibiotics that showed the highest activity against strains occurring most frequently (Klebsiella pneumoniae [n = 103] and Enterobacter cloacae [n = 85]) were tigecycline (102 [99.03%] of K. pneumoniae tested strains and 61 [100%] of E. cloacae strains were susceptible), colistin (33 [86.84%] of K. pneumoniae tested strains and 84 [100%] of E. cloacae were susceptible), and amikacin (86 [83.49%] of K. pneumoniae tested strains and 26 [30.58%] of E. cloacae strains were susceptible). CONCLUSIONS: Carbapenem resistance among Enterobacteriaceae isolates showed a trend to increase during the six-year period of study. Because infections caused by carbapenem-resistant strains are frequently life-threatening, the effective strategies to control the spreading of antibiotic resistance are necessary.


Assuntos
Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/classificação , Hospitais Universitários , Humanos , Testes de Sensibilidade Microbiana , Polônia , Estudos Retrospectivos , Especificidade da Espécie
14.
Molecules ; 17(4): 4612-24, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22513487

RESUMO

Ketoconazole (KET), an imidazole derivative with well-known antifungal properties, is lipophilic and practically insoluble in water, therefore its clinical use has some practical disadvantages. The aim of the present study was to investigate the influence of PAMAM-NH(2) and PAMAM-OH dendrimers generation 2 and generation 3 on the solubility and antifungal activity of KET and to design and evaluate KET hydrogel with PAMAM dendrimers. It was shown that the surface charge of PAMAM dendrimers strongly affects their influence on the improvement of solubility and antifungal activity of KET. The MIC and MFC values obtained by broth dilution method indicate that PAMAM-NH(2) dendrimers significantly (up to 16-fold) increased the antifungal activity of KET against Candida strains (e.g., in culture Candida albicans 1103059/11 MIC value was 0.008 µg/mL and 0.064 µg/mL, and MFC was 2 µg/mL and 32 µg/mL for KET in 10 mg/mL solution of PAMAM-NH(2) G2 and pure KET, respectively). Antifungal activity of designed KET hydrogel with PAMAM-NH(2) dendrimers measured by the plate diffusion method was definitely higher than pure KET hydrogel and than commercial available product. It was shown that the improvement of solubility and in the consequence the higher KET release from hydrogels seems to be a very significant factor affecting antifungal activity of KET in hydrogels containing PAMAM dendrimers.


Assuntos
Antifúngicos/química , Dendrímeros/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Cetoconazol/química , Antifúngicos/farmacologia , Química Farmacêutica , Cetoconazol/farmacologia , Testes de Sensibilidade Microbiana , Solubilidade
15.
Med Dosw Mikrobiol ; 64(1): 55-62, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-22808730

RESUMO

INTRODUCTION: Majority of nosocomial Acinetobacter baumannii strains are highly resistant to many available groups of antibiotics, causing therapy of infections the clinical challenge. The aim of study was to estimate of resistance development to sulbactam, cefoperazone and cefoperazone/sulbactam in Acinetobacter baumannii clinical strains. METHODS: Five Acinetobacter baumannii strains (Acb1, Acb2, Acb4, Acb13 and Acb25) were identified by the VITEK 2 GN card and the automatic system VITEK 2 according to the procedure and following the producer's instructions. Additionaly, the belonging of the strains to the species was confirmed by the presence of the bla(OXA-51-like) gene. Initial and after antibiotic exposure MIC values of sulbactam, cefoperazone and cefoperazone/sulbactam were determined by using a broth microdilution method. Antibiotic pressure of examined strains was performed in Mueller-Hinton broth containing 0,5x, 0,9x and 2x initial MIC of individual compounds during six-day passages and next six-day passages without antibiotic presence. The Mann-Whitney U test and Kruskal-Wallis non-prarametric Anova test were used to statistical analysis. RESULTS: Serial passaging of Acinetobacter baumannii strains in the presence of antibiotics caused permanent increasing MIC value independently of used concentrations in the majority of examined strains. The highest MIC value increase of sulbactam was found in Acb4 strain. Even after two passages this isolate changed MIC from 0.5 microg/ml to 4 microg/ml (increase about four levels of concentration). Moreover, after incubation in 0.9x MIC concentration similar observation was noted. No normalization of MIC value of sulbactam after incubation during next six passages without sulbactam was observed. In case of cefoperazone the highest levels of induction were noted in Acb1, Acb13 and Acb25 strains. In these strains, after two passages in presence of cefoperazone (2xMIC) the exceedance of minimal of growth concentration over the highest examined concentration was observed. Similar effects were observed in Acbl strain after stimulation with 0.9x and 0.5x MIC cefoperazone. Return of initial MIC values was received only after induction with 0.5 x MIC cefoperazone. In some cases, no opportunities for evaluation of resistance development was noted, because during stimulation with 2x MIC of used antibiotics concentarations, bactericidal effect was found. CONCLUSIONS: Sulbactam, cefoperazone and cefoperazone/sulbactam rapidly induce increasing of resistance in Acinetobacter baumannii clinical isolates. Statistically essential MIC increase after using higher concentration than lower was showed. This effect was particularly visible in the case of stimulation of cefoperazone/sulbactam combination.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Cefoperazona/farmacologia , Sulbactam/farmacologia , Acinetobacter baumannii/classificação , Testes de Sensibilidade Microbiana , Especificidade da Espécie
16.
Ann Agric Environ Med ; 29(2): 185-189, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35767749

RESUMO

INTRODUCTION: In the twentieth century, fumigation became a very popular method of disinfection, although in the same century many agents used as fumigants were withdrawn for ecological reasons. Fogging (fumigation) is a relatively new disinfection technology using dry fog, which behaves more like a gas and easily fills the sanitized space, reaching all surfaces in the room. The undoubted advantage of fumigation is the possibility of disinfecting difficult to clean areas. Fumigation has become particularly important in the twenty-first century due to procedures related to combating and preventing the spread of the coronavirus that causes COVID-19. OBJECTIVE: The aim of this review article is to summarize the current state of knowledge in the field of fumigation on the basis of past results of original research, taking into account new trends and possibilities of its application. BRIEF DESCRIPTION OF THE STATE OF KNOWLEDGE: Due to the fact that fumigation is safe for apparatus, equipment, and electronics, while simultaneously enabling the highest possible bactericidal and virucidal levels, this method is widely used in various areas, both medical and non-medical. Fogging technology is used in the medical, pharmaceutical, and food industries, as well as in transportation, for air fumigation or surface disinfection in closed spaces, such as hospital and laboratory rooms, incubators, refrigerators, ships, trucks, railway containers, and aircraft, to name only a few. The most common fumigants are hydrogen peroxide and peracetic acid, and their mechanism of action is related to their oxidizing properties. SUMMARY: Hydrogen peroxide and peracetic acid are highly effective and non-toxic fumigants that can be safely used for fogging laboratory and medical equipment, pharmaceutical facilities, hospital rooms, and animal breeding rooms.


Assuntos
COVID-19 , Ácido Peracético , Animais , COVID-19/prevenção & controle , Fumigação/métodos , Peróxido de Hidrogênio/farmacologia , Ácido Peracético/farmacologia , Preparações Farmacêuticas
17.
Front Public Health ; 10: 820816, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284381

RESUMO

Cars with air conditioning systems have become the norm, but these systems can be dangerous for human health as a result of the accumulation of different microorganisms, including pathogenic ones, causing severe allergy or inflammation problems. The novel purpose of this study is 2-fold: on the one hand, to test different disinfection agents on a new area, that is, automobile cabins, and on the other, to compare activity in the gas phase of these agents for disinfection of car air conditioning and cabin surfaces. This study shown that tested disinfectant agents dedicated for decontamination medical areas (agent based on peracetic acid and an agent containing didecyldimethylammonium chloride, 2-phenoxyethanol with cinnamaldehyde) can be successfully used for disinfection car air conditioning and cabin surfaces. Both disinfectants were examined in comparison to a commercial "ready-to-use" spray from a local supermarket dedicated to car air conditioning disinfection. Our research found that very effective agents in this regard were acid stabilized by hydrogen peroxide applied by fumigator, and a combination of didecyldimethylammonium chloride, 2-phenoxyethanol, and cinnamaldehyde applied by atomizer. Tested disinfection procedures of car air conditioning significantly influence the quality of cabin air and surfaces by reducing the amount of microorganisms. The comparison of disinfection properties studied agents in the gas phase reveal statistically significant differences between it effect for disinfection car air conditioning and cabin surfaces. Our research found that very effective agents in this regard were acid stabilized by hydrogen peroxide applied by fumigator, and a combination of didecyldimethylammonium chloride, 2-phenoxyethanol, and cinnamaldehyde applied by atomizer. Tested disinfection procedures of car air conditioning significantly influence the quality of cabin air and surfaces by reducing the amount of microorganisms.


Assuntos
Desinfetantes , Desinfecção , Desinfetantes/farmacologia , Desinfecção/métodos , Humanos , Peróxido de Hidrogênio , Ácido Peracético
18.
Cancers (Basel) ; 14(2)2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35053601

RESUMO

LncRNAs have arisen as new players in the world of non-coding RNA. Disrupted expression of these molecules can be tightly linked to the onset, promotion and progression of cancer. The present study estimated the usefulness of 14 lncRNAs (HAGLR, ADAMTS9-AS2, LINC00261, MCM3AP-AS1, TP53TG1, C14orf132, LINC00968, LINC00312, TP73-AS1, LOC344887, LINC00673, SOX2-OT, AFAP1-AS1, LOC730101) for early detection of non-small-cell lung cancer (NSCLC). The total RNA was isolated from paired fresh-frozen cancerous and noncancerous lung tissue from 92 NSCLC patients diagnosed with either adenocarcinoma (LUAD) or lung squamous cell carcinoma (LUSC). The expression level of lncRNAs was evaluated by a quantitative real-time PCR (qPCR). Based on Ct and delta Ct values, logistic regression and gradient boosting decision tree classifiers were built. The latter is a novel, advanced machine learning algorithm with great potential in medical science. The established predictive models showed that a set of 14 lncRNAs accurately discriminates cancerous from noncancerous lung tissues (AUC value of 0.98 ± 0.01) and NSCLC subtypes (AUC value of 0.84 ± 0.09), although the expression of a few molecules was statistically insignificant (SOX2-OT, AFAP1-AS1 and LOC730101 for tumor vs. normal tissue; and TP53TG1, C14orf132, LINC00968 and LOC730101 for LUAD vs. LUSC). However for subtypes discrimination, the simplified logistic regression model based on the four variables (delta Ct AFAP1-AS1, Ct SOX2-OT, Ct LINC00261, and delta Ct LINC00673) had even stronger diagnostic potential than the original one (AUC value of 0.88 ± 0.07). Our results demonstrate that the 14 lncRNA signature can be an auxiliary tool to endorse and complement the histological diagnosis of non-small-cell lung cancer.

19.
J Immunol ; 182(7): 4313-20, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19299731

RESUMO

Increased activity of IDO, which catalyzes the degradation of Trp into kynurenine (Kyn), is observed during HIV/SIV infection, and it may contribute to the persistence of HIV/SIV by suppressing antiviral T cell responses. We administered the IDO inhibitor 1-methyl-d-tryptophan (d-1mT) for 13 days to SIV-infected rhesus macaques receiving antiretroviral therapy (ART). d-1mT treatment increased the plasma levels of Trp, without reducing the levels of Kyn, suggesting only a partial effect on IDO enzymatic activity. Surprisingly, d-1mT significantly reduced the virus levels in plasma and lymph nodes of ART-treated animals with incomplete responsiveness to ART. In SIV-infected animals that were not receiving ART, d-1mT was ineffective in reducing the plasma viral load and had only a marginal effect on the plasma Kyn/Trp ratio. Increased IDO and TGF-beta mRNA expression in lymph nodes of ART-treated macaques after d-1mT treatment suggested that compensatory counterregulatory mechanisms were activated by d-1mT, which may account for the lack of effect on plasma Kyn. Finally, d-1mT did not interfere with the ART-induced T cell dynamics in lymph nodes (increased frequency of total CD4 T cells, increase of CD8 T cells expressing the antiapoptotic molecule Bcl2, and reduction of regulatory T cells). Thus, d-1mT appeared to synergize with ART in inhibiting viral replication and did not interfere with the beneficial immunologic effects of ART. Further studies are required to elucidate the immunologic or virologic mechanism by which d-1mT inhibited SIV replication in vivo.


Assuntos
Antirretrovirais/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Triptofano/análogos & derivados , Animais , Cromatografia Líquida de Alta Pressão , Quimioterapia Combinada , Citometria de Fluxo , Cinurenina/sangue , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Macaca mulatta , RNA Mensageiro/análise , RNA Viral/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/efeitos dos fármacos , Triptofano/administração & dosagem , Triptofano/sangue , Viremia/tratamento farmacológico
20.
Biol Pharm Bull ; 34(7): 1129-33, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21720026

RESUMO

Clotrimazole (CLO) is a local imidazolic antifungal agent. A major problem associated with the successful formulation of effective dosage forms containing CLO is its poor aqueous solubility, which presents a hindrance for the local availability of CLO and limits the effective antifungal therapy. In the present study, the effects of various concentrations of poly(amidoamine) (PAMAM) dendrimers generation 2 (G2) and generation 3 (G3) with amine (PAMAM-NH(2)) or hydroxyl surface groups (PAMAM-OH) on aqueous solubility and antifungal activity of CLO were studied. The obtained results showed that all tested PAMAM dendrimers improved the solubility of CLO and the more potent were PAMAM-NH(2) dendrimers. The increase in solubility of CLO was highest at dendrimer concentration of 10 mg/ml. Microbiology studies indicated that only PAMAM-NH(2) dendrimers significantly increased the antifungal activity of CLO (a 4-32-fold increase in the antifungal activity compared to pure CLO) and the most potent was dendrimer PAMAM-NH(2) G2. These observations indicate that PAMAM dendrimers might be considered as potential carriers of CLO and provide further impetus to evaluate these polymers for use in basic drug delivery studies and to design semisolid dosage forms based on dendrimers with antimicrobial drugs, like CLO.


Assuntos
Antifúngicos/farmacologia , Clotrimazol/farmacologia , Dendrímeros/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Solubilidade
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