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Purpose: Today, Enterococcus species are one of the most frequent etiological agents in nosocomial infections. The aim of this study was to determine the susceptibility to antibiotics and the prevalence of high-level aminoglycoside resistance (HLAR) among Enterococcus strains. Materials and methods: The susceptibility of 85 isolates of Enterococcus (47 E. faecalis and 38 E. faecium) was determined using the disk diffusion method. The results were interpreted according to European Committee on Antimicrobial Suscepti-bility Testing (EUCAST) guidelines. PASW Statistics 17.0 was used for statistical analysis. Results: E. faecalis strains showed the highest susceptibility to ampicillin, tigecycline, vanco-mycin, imipenem, and linezolid and E. faecium to linezolid, tigecycline, and quinupristin/dalfopristin. Among all tested strains, high-level gentamicin resistance (HLGR) was found in 4% of E. faecalis and 8% of E. faecium strains, high-level strepto-mycin resistance (HLSR) in 45% and 42%, and HLAR in 50% and 32% of strains, respectively. HLGR was detected only in vancomycin-resistant Enterococcus (VRE)- strains (12%), while HLSR in 76.9% of VRE+ and 24% of VRE- strains, and HLAR in 23.1% of VRE+ and 64% of VRE- strains. The tested strains were also divided into two groups: HLSR+ and HLAR+. In both groups, statistically significant susceptibility differences (p<0.05) were found for ampicillin, imipenem and trimethoprim/sulfamethoxazole. The most frequent antibiotic resistance profile among E. faecalis strains was SR (resistance phenotype to strepto-mycin), and among E. faecium, AMPR, IMPR, CNR, SR, SXTR (ampicillin, imipenem, gentamicin, streptomycin, trimethoprim/sulfamethoxazole). Conclusions: This study showed the slowly increasing prevalence of HLAR and resistance to newer antibiotics (linezolid and tigecycline) among Enterococcus strains. It is necessary to search for new directions in the treatment of enterococcal infections. [ABSTRACT FROM AUTHOR]

The increasing prevalence of acquired carbapenemases in Gram - negative bacteria is one of the biggest problems in the prevention and therapy of infectious diseases. NDM (New Delhi Metallo-β-Lactamase) is a recently discovered enzyme which has the ability to hydrolyze all β-lactam antibiotics, except aztreonam. Making that scenario more worrisome is the fact that mobile fragments of DNA carrying blaNDM genes, also keeps a number of other genes encoding antibiotic resistance. NDM enzymes are currently present in different species of bacteria all over the world. NDM-producing bacteria are resistant to virtually all available antimicrobial agents except tigecycline, colistine and fosfomycine. [ABSTRACT FROM AUTHOR]

Introduction: Pseudomonas aeruginosa rods are increasingly causing serious infections in hospitalized patients. Particularly worrying is the increase of resistance to carbapenems antibiotics. Purpose: To evaluate susceptibility and the occurrence of genes (blaIMP and blaVIM) encoding resistance to carbapenems among Pseudomonas aeruginosa strains. Materials and methods: Studies were conducted for 50 strains of Pseudomonas aeruginosa (25 susceptible and 25 resistant to imipenem). Susceptibility to antibiotics was tested using the diffusion method and discs with antibiotics and / or strips with gradient concentrations of antibiotics. In the second phase we tested the ability of MBL production by all strains using the CD and DDST technique described in the literature. The next stage of the study was to evaluate the prevalence of carbapenems resistance genes. These studies were performed by PCR technique. Results: The studies found in both groups of Pseudomonas aeruginosa rods similar percentage of strains resistant to aminoglycoside antibiotics (from 72% to 88%) and ciprofloxacin (84%). There was no presence of the genes in any of the tested groups of Pseudomonas aeruginosa. Conclusion: Pseudomonas aeruginosa strains resistant to imipenem no posses blaIMP and blaVIM genes therefore their resistance was conditioned by the presence of other mechanisms. Antibiotics with high activity against Pseudomonas aeruginosa strains resistant to imipenem were polymyxin B (100% susceptible strains) and colistin (96% susceptible strains). [ABSTRACT FROM AUTHOR]

Abstract Background HIV-I can be transmitted by intravenous inoculation of contaminated blood or blood product or sexually through mucosal surfaces. Here we performed a pilot study in the SIVmac251 macaque model to address whether the route of viral entry influences the kinetics of the appearance and the size of virus-specific immune in different tissue compartments. Methods For this purpose, of 2 genetically defined Mamu-A*01-positive macaques, 1 was exposed intravenously and the other intrarectally to the same SIVmac251 viral stock and virus-specific CD8+ T-cells were measured within the first 12 days of infection in the blood and at day 12 in several tissues following euthanasia. Results Virus-specific CD8+ T-cell responses to Gag, Env, and particularly Tat appeared earlier in the blood of the animal exposed by the mucosal route than in the animal exposed intravenously. The magnitude of these virus-specific responses was consistently higher in the systemic tissues and GALT of the macaque exposed by the intravenous route, suggesting a higher viral burden in the tissues as reflected by the faster appearance of virus in plasma. Differences in the ability of the virus-specific CD8+ T-cells to respond in vitro to specific peptide stimulation were also observed and the greatest proliferative ability was found in the GALT of the animal infected by the intrarectal route. Conclusions These data may suggest that the natural mucosal barrier may delay viral spreading. The consequences of this observation, if confirmed in studies with a larger number of animals, may have implications in vaccine development.

Enterobacterales (especially carbapenem-resistant) are considered an urgent threat to public health. The available antibiotic therapy is limited due to the increase of multidrug-resistant (MDR) strains. Tigecycline, a minocycline derivative, has emerged as a potential key agent in the treatment of MDR isolates. The aim of the study was to evaluate the synergistic effect of tigecycline in combination with nine antimicrobial agents-ceftazidime/avibactam, colistin, ertapenem, gentamicin, imipenem, levofloxacin, meropenem/vaborbactam, polymyxin B, and rifampicin. Eighty clinical Enterobacter cloacae strains were obtained from patients of two University Hospitals in Bialystok, Poland. The E-test method was used to determine synergistic interactions. Among all combinations, synergy was reported in 61% of cases, addition in 32%, and indifference in 7%. The highest synergy rates were observed in tigecycline combinations with: ceftazidime/avibactam (60/80; 75%), imipenem (60/80; 75%), polymyxin B (55/80; 68.75%) and rifampicin (55/80; 68.75%), while the lowest synergy rate was noted in tigecycline-levofloxacin (26/80; 32.5%). The tigecycline-gentamicin showed the highest rate of indifference; antagonism, was not observed in any combination. In conclusion, tigecycline appears more suitable for use in combination therapy rather than as monotherapy and can be effectively paired with various antimicrobial agents against MDR E . cloacae . Further research will be necessary to confirm these results., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Korczak, Majewski, Rombel, Iwaniuk, Sacha, Modzelewski and Tryniszewska.)

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., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Korczak, Majewski, Iwaniuk, Sacha, Matulewicz, Wieczorek, Majewska, Wieczorek, Radziwon and Tryniszewska.)

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.

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., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Bukłaha, Wieczorek, Kruszewska, Majewski, Iwaniuk, Sacha, Tryniszewska and Wieczorek.)

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.

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 Białystok, 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., (© 2021. The Author(s).)

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., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Klebsiella pneumoniae infections have always been an important problem in public health, but today, the increasing resistance of these bacteria to antibiotics due to β-lactamases production has renewed interest in K. pneumoniae infections. The aim of the study was to present a case of a neurosurgical patient with multidrug-resistant K. pneumoniae ST11 infection after craniectomy. Four K. pneumoniae isolates from various clinical materials of the patient undergone identification and susceptibility testing with the Vitek2 system. Tests for β-lactamases production were performed according to EUCAST guidelines. Strains were analyzed for bla genes responsible for β-lactamase production (bla TEM , bla SHV , bla CTX-M , bla VIM , bla IMP , bla NDM , bla KPC , bla OXA-48 ) using PCR. Moreover, the genetic relatedness of these isolates was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). All tested strain presented multidrug resistance. The highest susceptibility was observed for imipenem, meropenem, and ertapenem. The strain isolated from the nervous system was ESBL-positive with bla SHV-11 , bla TEM-1 , and bla CTX-M-15 genes. Additionally, the strain from urine was bla KPC-3 -positive. Molecular typing revealed that all strains belonged to the same clone and identified two PFGE profiles. The analysis of MLST allelic profile showed that tested K. pneumoniae strains belonged to ST11. Identification of ST11 K. pneumoniae as etiological factor of infection unfavorably impacts on prognosis among neurosurgical patient after craniectomy.

The aim of this study was to investigate the synergy between ceftazidime-avibactam, ertapenem, fosfomycin, and tigecycline against carbapenemase-producing Klebsiella pneumoniae using the E test MIC:MIC (minimum inhibitory concentration) ratio synergy method. The results were interpreted using fractional inhibitory concentration index (FICI) to describe the effects of antimicrobial combinations in vitro . To assess the clinical significance of each antibiotic combination, the susceptible breakpoint index (SBPI) was calculated for each combination, and within each strain. The FICI method revealed that the most synergistic combinations against carbapenemase-producing K. pneumoniae were ceftazidime-avibactam with ertapenem and ceftazidime-avibactam with fosfomycin. This effect was demonstrated in 47% (9/19) of all tested clinical K. pneumoniae isolates. Considering the effects of all drug combinations in K. pneumoniae harboring bla KPC , bla NDM , and bla OXA-48 genes, we observed that the combination of ceftazidime-avibactam with fosfomycin was the most synergistic in New Delhi metallo-β-lactamase (NDM)-producing K. pneumoniae , and the combination of ceftazidime-avibactam with ertapenem was the most synergistic in K. pneumoniae carbapenemase (KPC)-producing K. pneumoniae . In addition, all tested combinations were synergistic against oxacillinase (OXA)-48-producing K. pneumoniae , except the combination of ceftazidime-avibactam with tigecycline. The SBPI index showed that ceftazidime-avibactam in combination with fosfomycin reduced the MIC to less than the susceptibility breakpoint among all tested carbapenemase-producing K. pneumoniae . Moreover, the combinations of ceftazidime-avibactam with ertapenem, and ceftazidime-avibactam with tigecycline were able to reduce the MIC to less than the susceptibility breakpoint in all KPC- and OXA-48-producing K. pneumoniae .

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.

Purpose: Over the past years, an increase in resistance to aminoglycosides has been observed among Enterobacteriaceae rods. This resistance development reduces therapeutic options for infections caused by multidrug-resistance organisms. Because of the changing epidemiology of extended-spectrum β-lactamases (ESBLs) and resistance to aminoglycosides, we investigated the prevalence of the aac(3)-Ia, aac(6')-Ib, ant(4')-IIa, ant(2")-Ia, and aph(3")-Ib genes encoding aminoglycoside-modifying enzymes (AMEs) in ESBL-producing Escherichia coli as well as ESBL-non-producing isolates. To understand bacterial resistance to aminoglycoside antibiotics, we estimated resistance phenotypes and the presence of genes responsible for this resistance., Materials and Methods: The study was conducted on 44 E.coli strains originated from patients hospitalized at University Hospital of Bialystok. MIC values were obtained for gentamicin, amikacin, netilmicin, and tobramycin. Isolates were tested for the presence of the aac(3)-Ia, aac(6')-Ib, ant(4')-IIa, ant(2")-Ia, and aph(3")-Ib genes with the use of the PCR technique., Results: Resistance to aminoglycosides was found in 79.5% of the isolates. The highest percentages of resistance were observed for tobramycin (70,5%) and gentamicin (59%), followed by netilmicin (43.2%) and amikacin (11.4%). PCR assays revealed the presence of aac(6')-Ib among 26 (59.2%) strains, aph(3")-Ib among 16 (36.2%), aac(3)-Ia among 7 (15.9%), and ant(2")-Ia among 2 (4.6%) strains., Conclusions: The enzymatic resistance against aminoglycosides in northeastern Poland among clinical isolates of E. coli is predominantly caused by aac(6')-Ib and aph(3")-Ib. Amikacin may be used for therapy of infections caused by ESBL-producing E. coli, because of the low rates of resistance., (Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.)

Objectives: The growing incidence of multidrug-resistant (MDR) bacteria is an emerging challenge in modern medicine. The utility of carbapenems, which are considered 'last-line' agents, is being diminished by the growing incidence of various resistance mechanisms in Gram-negative bacteria. A molecular investigation was performed of an MDR carbapenem-resistant Citrobacter freundii of sequence type 8 (ST8) isolated from a hematology patient with acute myeloid leukemia., Methods: Multilocus sequence typing and analysis of the nucleotide sequence of the class I integron were performed using PCR and Sanger sequencing. Transformation of the resistance plasmid isolated following the alkaline lysis method was performed using chemically competent E. coli TOP10., Results: Molecular analysis of the carbapenem-resistant C. freundii revealed the presence of the VIM-4 isoenzyme located on the ∼55-kb transferable resistance plasmid. Interestingly, the bla VIM-4 gene was inserted into an unusual gene cassette containing a 169-bp direct repeat of the 3' segment of the bla VIM-4 gene., Conclusions: All unusual gene cassettes containing VIM-DR (direct repeat) described thus far have been harbored by non-fermenters, i.e., Acinetobacter and Pseudomonas, underscoring the importance of resistance determinant mobility, which may go even beyond genus, family, and order boundaries. Great efforts need to be taken to explore pathways of resistance to 'last-resort' antimicrobials, especially among clinically relevant pathogens., (Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The growing incidence of multidrug-resistant (MDR) bacteria is an emerging challenge in modern medicine. The utility of carbapenems, considered "last-line" agents in therapy of infections caused by MDR pathogens, is being diminished by the growing incidence of various resistance mechanisms. Enterobacter cloacae have lately begun to emerge as an important pathogen prone to exhibiting multiple drug resistance. We aimed to investigate the molecular basis of carbapenem-resistance in 44 E. cloacae clinical strains resistant to at least one carbapenem, and 21 susceptible strains. Molecular investigation of 65 E. cloacae clinical strains was based on quantitative polymerase chain reaction (qPCR) allowing for amplification of ampC, ompF , and ompC transcripts, and analysis of nucleotide sequences of alleles included in MLST scheme. Co-operation of three distinct carbapenem resistance mechanisms has been reported-production of OXA-48 (5%), AmpC overproduction (97.7%), and alterations in outer membrane (OM) transcriptome balance. Carbapenem-resistant E. cloacae were characterized by (1.) downregulation of ompF gene (53.4%), which encodes protein with extensive transmembrane channels, and (2.) the polarization of OM transcriptome-balance (79.1%), which was sloped toward ompC gene, encoding proteins recently reported to possess restrictive transmembrane channels. Subpopulations of carbapenem-susceptible strains showed relatively high degrees of sequence diversity without predominant types. ST-89 clearly dominates among carbapenem-resistant strains (88.6%) suggesting clonal spread of resistant strains. The growing prevalence of pathogens resistant to all currently available antimicrobial agents heralds the potential risk of a future "post-antibiotic era." Great efforts need to be taken to explore the background of resistance to "last resort" antimicrobials.

The aim of the study was to evaluate the prevalence of OXA and other β-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 β-lactamase genes such as blaVIM-2, blaVIM-4, blaSHV-5, and blaTEM-1. All isolates were susceptible only to colistin (100%).

The present study was conducted to investigate the prevalence of genes encoding resistance to aminoglycosides and fluoroquinolones among twenty-five Pseudomonas aeruginosa isolated between 2002 and 2009. In PCR, following genes were detected: ant(2″)-Ia in 9 (36.0%), aac(6')-Ib in 7 (28.0%), qnrB in 5 (20.0%), aph(3″)-Ib in 2 (8.0%) of isolates.

An increase in the antibiotic resistance among Enterococcus faecium strains has been observed worldwide. Moreover, this bacteria has the ability to produce several virulence factors and to form biofilm that plays an important role in human infections. This study was designed to compare the antibiotic resistance and the prevalence of genes encoding surface protein (esp), aggregation substance (as), surface adhesin (efaA), collagen adhesin (ace), gelatinase (gelE), and hialuronidase (hyl) between biofilm-producing and non-producing E. faecium strains. Therefore, ninety E. faecium clinical isolates were tested for biofilm-forming ability, and then were assigned to two groups: biofilm-positive (BIO(+), n =70) and biofilm-negative (BIO(-), n = 20). Comparison of these groups showed that BIO(+) isolates were resistant to β-lactams, whereas 10% of BIO(-) strains were susceptible to ampicillin (statistically significant difference, p = 0.007) and 5% to imipenem. Linezolid and tigecycline were the only antibiotics active against all tested isolates. Analysis of the virulence factors revealed that ace, efaA, and gelE genes occurred more frequently in BIO(-) strains (ace in 50% BIO(+) vs. 75% BIO(-); efaA 44.3% vs. 85%; gelE 2.9% vs. 15%, respectively), while hyl gene appeared more frequently in BIO(+) isolates (87.1% BIO(+) vs. 65% BIO(-)). These differences were significant (p < 0.05). We concluded that BIO(+) strains were more resistant to antibiotics than BIO(-) strains, but interestingly, BIO(-) isolates were characterized by possession of higher virulence capabilities.

An increase in the antibiotic resistance among members of the Enterobacteriaceae family has been observed worldwide. Multidrug-resistant Gram-negative rods are increasingly reported. The treatment of infections caused by Escherichia coli and other Enterobacteriaceae has become an important clinical problem associated with reduced therapeutic possibilities. Antimicrobial carbapenems are considered the last line of defense against multidrug-resistant Gram-negative bacteria. Unfortunately, an increase of carbapenem resistance due to the production of Klebsiella pneumoniae carbapenemase (KPC) enzymes has been observed. In this study we describe the ability of E. coli to produce carbapenemase enzymes based on the results of the combination disc assay with boronic acid performed according to guidelines established by the European Community on Antimicrobial Susceptibility Testing (EUCAST) and the biochemical Carba NP test. Moreover, we evaluated the presence of genes responsible for the production of carbapenemases (bla KPC, bla VIM, bla IMP, bla OXA-48) and genes encoding other β-lactamases (bla SHV, bla TEM, bla CTX-M) among E. coli isolate. The tested isolate of E. coli that possessed the bla KPC-3 and bla TEM-34 genes was identified. The tested strain exhibited susceptibility to colistin (0.38 μg/mL) and tigecycline (1 μg/mL). This is the first detection of bla KPC-3 in an E. coli ST479 in Poland.

We investigated the genetic similarities and expression of the MexAB-OprM efflux pump system in different clones of multiresistant Pseudomonas aeruginosa strains collected from 2002 to 2009 at two intensive care units (ICU). Regulatory and structural genes mexB, mexR, and mexA were found in 99%, 98%, and 94% of tested strains, respectively. The presence of class 1 integron was found in 90% of the strains, while class 2 integron in only one strain (Psa506). Class 3 integron was not found in any of the tested strains. Among the eleven clones identified, only two clones, I and D, exhibited higher levels of mexB gene expression than the other clones. Clone I had the highest expression (FC = 10.36, p < 0.05). The results of our study indicated a high level of MexAB-OprM pump expression in groups of strains isolated in the years 2008-2009 (FC = 12.92, p < 0.03) and 2002-2006 (FC = 5.14, p < 0.03). There were no statistically significant differences in resistance to all tested antibiotics among the various clones. The high level of antimicrobial resistance may have been due to the coexistence of different resistance mechanisms among the studied P. aeruginosa strains. However, this does not exclude the contribution of the MexAB-OprM pump, particularly in resistance to meropenem and ciprofloxacin., (© 2014 APMIS. Published by John Wiley & Sons Ltd.)

Acinetobacter baumannii has emerged as a highly problematic hospital-associated pathogen. Different mechanisms contribute to the formation of multidrug resistance in A. baumannii, including the AdeABC efflux system. Distribution of the structural and regulatory genes encoding the AdeABC efflux system among genetically diverse clinical A. baumannii strains was achieved by using PCR and pulsed-field gel electrophoresis techniques. The distribution of adeABRS genes is extremely high among our A. baumannii strains, except the adeC gene. We have observed a large proportion of strains presenting multidrug-resistance phenotype for several years. The efflux pump could be an important mechanism in these strains in resistance to antibiotics., (© 2013.)

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., (© 2013 Blackwell Verlag GmbH.)

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.

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.

The aim of this study was to investigate the prevalence of the aacA4 gene in a population of multidrug resistant strains of P. aeruginosa isolated from bronchial secretions obtained from the Intensive Therapy Unit (ITU). Twelve MDR isolates were tested for antibiotic susceptibility and the presence of the aacA4 gene. In this study, 58.3% of the strains contained (6')-Ib' aminoglycoside acetyltransferase gene. All of the studied strains (aacA4-positive and aacA4-negative) were susceptible only to colistine (100%). Among other antibiotics, the lowest resistance rates were those shown against ceftazidime (14.3% to 20%) and imipenem (28.6% to 40%). Our studies frequently revealed the presence of the aacA4 gene as a factor responsible for resistance; it is probable that other mechanisms of resistance to aminoglycoside antibiotics also occurred.

Acinetobacter baumannii plays an increasing role in the pathogenesis of infections in humans. The bacilli are frequently isolated from patients treated in intensive care units. A growing resistance to antibiotics is leading to the emergence of strains that are multidrug-resistant and resistant to all available agents. The objective of this study was to assess susceptibility to antibiotics and to determine the presence and current level of the extended-spectrum β-lactamases (ESBLs) and attempt to isolate the Acinetobacter baumannii strain carrying the blaPER gene. A total of 51 strains of A. baumannii identified by phenotypic features were examined. That the strains belonged to the species was confirmed by the presence of the blaOXA-51-like; gene. A broth microdilution method was used for antibacterial susceptibility testing. The occurrence of ESBLs was determined using phenotypic double-disk synergy tests. The PCR technique was used to confirm the presence of the blaPER-1; gene encoding ESBL. The most active antibiotics were meropenem, cefepime and ampicillin/sulbactam, with susceptibility shown by 76.5%, 60.8% and 56.9% of the strains, respectively. The strains exhibited the highest resistance (&gt; 75%) to piperacillin, tetracycline, ciprofloxacin and cefotaxime. Phenotypic tests revealed ESBL mechanism of resistance in approximately 20% of Acinetobacter baumannii isolates. However, the PCR technique did not confirm the presence of the blaPER-1; gene in any of the Acinetobacter baumannii strains examined in our hospital. Acinetobacter baumannii strains demonstrate considerable resistance to many groups of antibiotics. Our findings indicate the involvement of enzymes belonging to families other than PER β-lactamase in resistance to β-lactams in A. baumannii.

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.

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.

The chemical composition of the essential oil obtained from the roots of Bidens tripartita L. by hydrodistillation was investigated by gas chromatography-mass spectrometry. In total, 106 compounds were identified (97.1% of the total oil). The main components of the oil were α-pinene (15.0%), β-bisabolene (9.3%), p-cymene (6.0%), hexanal (5.7%), linalool (4.6%), p-cymene-9-ol (3.4%), β-elemene (2.6%), 2-pentylfuran (2.2%), and silphiperfol-6-ene (2.1%). The antibacterial and antifungal properties of the essential oil were evaluated against eight Gram-positive and 11 Gram-negative bacterial species and 10 fungal strains. The oil exhibited a strong antifungal activity.

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.

Extended spectrum β-lactamases production is one of the most common mechanism of resistance to extended spectrum β-lactam antibiotics is increasing worldwide. Twenty five strains of Klebsiella pneumoniae isolated from clinical specimens were tested. Based on the phenotypic confirmatory test all these strains were defined as ESBL producers named ESBL(+). The plasmid DNA from each strains was used to investigate the presence of blaSHV genes responsible for extended spectrum β-lactamases production. Moreover, susceptibility of these strains to antibiotic other than β-lactams in was tested.

Antiproliferative and antifungal activities of essential oils from Erigeron acris root and herb and from Erigeron annuus herb were investigated. The cell viability assay was performed in cultured fibroblasts, cancer cell lines (MCF-7 and MDA-MBA-231), and endometrial adenocarcinoma (Ishikawa) cells as well as colon adenocarcinoma (DLD-1) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The essential oil from E. acris root showed the highest antiproliferative activity in the MCF-7 cell line with an IC50 value of 14.5 microg/mL. No effect of the essential oil on normal cells at that concentration was found. Antifungal activity against various strains of five Candida species, i.e. C. albicans, C. glabrata, C. tropicalis, C. krusei, and C. parapsilosis, was tested by the microdilution method. It was found that all examined oils can be useful as antifungal agents against the above-mentioned species, but the essential oil of E. acris herb was the most active. Their minimum inhibitory concentrations (MIC) ranged from 30 to 0.4 microL/mL. The data presented suggest that essential oils from E. acris and E. annuus possess antifungal activity against Candida spp. and antiproliferative activity against breast cancer MCF-7 cells.

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.

Antimicrobial resistance due to the continuous selective pressure from widespread use of antimicrobials in humans, animals and agriculture has been a growing problem for last decades. KPC beta-lactamases hydrolyzed beta-lactams of all classes. Especially, carbapenem antibiotics are hydrolyzed more efficiency than other beta-lactam antibiotics. The KPC enzymes are found most often in Enterobacteriaceae. Recently, these enzymes have been found in isolates of Pseudomonas aeruginosa and Acinetobacter spp. The observations of blaKPC genes isolated from different species in other countries indicate that these genes from common but unknown ancestor may have been mobilized in these areas or that blaKPC-carrying bacteria may have been passively by many vectors. The emergence of carbapenem resistance in Gram-negative bacteria is worrisome because the carbapenem resistance often may be associated with resistance to many beta-lactam and non-beta-lactam antibiotics. Treatment of infections caused by KPC-producing bacteria is extremely difficult because of their multidrug resistance, which results in high mortality rates. Therapeutic options to treat infections caused by multiresistant Gram-negative bacteria producing KPC-carbapenemases could be used polymyxin B or tigecycline.

Chronic venous disease (CVD) is an insufficiency of distal veins caused by their partial or total obstruction, endothelial distension and functional disorders. Chronic venous disease of lower limbs is common problem and affects millions of people. In this article we suggest that inflammatory process is involved in the structural remodeling in venous valves and in the venous wall, leading to valvular incompetence and the development of varicose veins.