The activity of silver nanoparticles (axonnite) on clinical and environmental strains of Enterococcus spp.

AIMS: The spread of bacterial antibiotic resistance among clinical strains is a growing problem nowadays. Resistance in Enterococcus spp. strains has merited special concern of late, as they have become significant nosocomial pathogens. Hence, the use of compounds such as silver nanoparticles (AgNPs), displaying various mechanisms of action, is a growing new approach against virulent, drug-resistant infections. Therefore, the activity of AgNPs obtained by a physical method (microexplosion method) was tested against 30 clinical and environmental Enterococcus spp. strains presenting diverse virulence and resistance patterns. RESULTS: The minimal inhibitory concentration for all the species ranged from 0.39 to 3.125 µg/ml. No statistical differences (p=0.26) were found between resistance to AgNPs and resistance to antibiotics, suggesting high activity of AgNPs even against multidrug-resistant strains. CONCLUSIONS: AgNPs obtained by this method seem to be a promising alternative to chemotherapeutics in the treatment or prevention of enterococcal infections.

Frequency of ace, epa and elrA Genes in Clinical and Environmental Strains of Enterococcus faecalis.

Surface proteins play an important role in the pathogenesis of enterococcal infections. Some of them are candidates for a vaccine, e.g., the frequency of endocarditis in rats vaccinated with Ace protein was 75 % as 12 opposed to 100 % in those who weren't. However, there are other components of enterococcal cells, such as Epa antigens or internalin-like proteins, which may be used in the prophylaxis of infections caused by them. However, also other virulence factors and resistance to antibiotics are important during enterococcal infection. Therefore, the relevance of ace, epa, elrA, other virulence genes, as well as resistance to antibiotics was investigated. 161 Enterococcus faecalis strains isolated from teaching hospitals in Lodz, cultured according to standard microbiological methods, were investigated for the presence of genes encoding surface proteins by PCR. Results were analyzed with χ(2) test. The elrA gene was found in all clinical and environmental strains, the ace gene was also widespread among E. faecalis (96.9 %). Both tested epa genes were found in the majority of isolates (83.25 %). There was correlation between the presence of esp and ace genes (p = 0.046) as well as between epa and agg genes (p = 0.0094; χ(2) test). The presence of the genes encoding surface proteins investigated in our study in the great majority of isolates implies that they would appear to be required during E. faecalis infection. Therefore, they could be excellent targets in therapy of enterococcal infections or, as some studies show, candidates for vaccines.

[Antiviral drugs]. / Leki przeciwwirusowe.

It is 50 years since the first antiviral drug--JUDR for the local herpes keratitis was introduced and over 25 years since HIV/AIDS was isolated and the Noble Prize in Medicine and Physiology was given to its discovers. Now, there are 50 antiviral drugs, in which 25 are for HIV, the others are for herpes virus, shingles, cytomegalovirus, hepatitis virus and influenza A virus. Drugs for hemorrhagic fever Ebola and Marbourg as well as Denga fever are under way In the paper the current knowledge on chemotherapy and prophylaxis is presented in the following viral infections: HIV, HBV, HCV, CMV, HSV, shingles and other. The paper also demonstrates different groups of antiviral drugs, their use and efficacy. Mechanisms of infections and activity of antiviral drugs are analyzed.

[Occurrence of virulence genes among Enterococcus faecalis strains isolated from patients and hospital environment]. / Wystepowanie genów zjadliwosci wsród szczepów Enterococcus faecalis izolowanych od pacjentów i ze srodowiska szpitalnego.

The aim of this study was to evaluate occurrence of virulence genes among Enterococcus faecalis strains isolated from two hospitals in Lódz, during 2005-2006. The second goal was to determine possible relationship between presence of those genes, resistance to ampicillin and sources of isolation. Enterococcal strains were identified to the species by PCR with ddl primers. All 161 isolates were tested for the presence of aggregation substance gene (agg), cytolisine genes (cyl-L, cyl-S), esp protein gene, gelatinase gene (gelE), serine protease gene (sprE). Susceptibility to ampicillin was tested by microdillution method. Both cyl-L and cyl-S genes were found in 52,2% of strains, agg gene was present in 62,73% isolates, esp gene--in 71.2%. Most frequently found genes were gelE (85.1%) and sprE (82.6%). The presence of esp gene in isolates resistant to ampicillin was statistically higher than in susceptible strains, what might suggest appearance of epidemic strains. Besides, strains possessing both, cyl-L/S and esp genes, were found to be statistically more often isolated strains than those possessing only single genes.

Relationship between urinary tract infection and self-retaining Double-J catheter colonization.

BACKGROUND AND PURPOSE: Long-term ureteral stenting is associated with bacterial colonization of both catheter surface and urine. The aim of the study was to evaluate the correlation between the type of bacteria cultured from the Double-J catheter, removed from urinary tract, and cultured from urine. Relationship of the Double-J catheter and urine culture with the duration of Double-J stenting, gender, the presence of diabetes mellitus, as well as the reason for stenting and manner of catheter insertion was also evaluated. PATIENTS AND METHODS: Sixty-five patients were enrolled in the study. Urine specimens were cultured before stent insertion and removal. The stent was sent immediately for culture. Data such as age, sex, presence of diabetes mellitus, reason for stenting, and manner of catheterization were recorded. RESULTS: Urine cultures were positive in 17 cases, while catheter cultures were positive in 64 cases. In 10 cases, the same bacterial species were colonized from urine and stent surface, while in one case, both cultures were negative. In seven patients, both cultures showed different bacterial species, and in 47 cases, urine cultures were negative while the catheters were colonized. CONCLUSIONS: The only significant correlation was noted between urine culture and stenting duration (P < 0.05). Double-J catheter retention in the urinary tract is associated with a high risk of bacterial colonization, while the risk of urine infection is about fourfold lower. There is a great discrepancy between urine and catheter cultures.

[Susceptibility to antimicrobial agents and genotypic relatedness of enterococcal strains isolated from patients and hospital environment]. / Lekowrazliwosc i pokrewienstwo szczepów Enterococcus sp. izolowanych od pacjentów i ze srodowiska szpitalnego.

The aim of this study was to evaluate antibiotic susceptibility of Enterococcus sp. strains isolated from two hospitals in lódz, during 2005-2006. The second goal was to determine possible transmission of these strains within hospital wards by using melting profile PCR. Enterococcal strains were identified to species according standard microbiological methods. There was isolated 159 strains of E. faecalis, 51 strains of E. faecium and two E. avium, 1 E. durans. Susceptibility to antimicrobial agents was tested by disc diffusion method. None of these strains was resistant to vancomycin, teicoplanin or linezolid. There was high percentage of strains resistant to aminoglicosides, 22% of E. faecalis strains, and 54.9% of E. faecium strains, respectively. Additionally it was shown that 11.7% of E. faecium is resistant to chinuprisin-dalfopristin. The strains with similar pattern of resistance to antibiotics and fenotypic characteristics were genotyped by mpPCR. This technique was useful to confirm relatedness of bacterial strains suspected of being spread within hospital wards.

[Clonal transmission of methicillin-resistant S. aureus (MRSA) strain in two surgical wards in Lódz]. / Klonalna transmisja metycylino-opornego szczepu S. aureus (MRSA) w dwóch oddzialach zabiegowych szpitala lódzkiego.

OBJECTIVE: Phenotypic and genotypic characteristics of S. aureus strains isolated from selected operative wards. METHODS: A group of 50 strains were analysed. Bacterial strains were isolated from three operative wards of Pirogow Specialistic Hospital in Lódz in a year. Biochemical properties and drug resistance were estimated using standard microbiological techniques. PCR MP technique was used for genotypic analysis. MAIN OBSERVATIONS: A convergence of genotyping results and antibiotic resistance profiles among MRSA strains was observed. Thus, the antibiogram may serve as the instrument for the preliminary typing of S. aureus strains that may be related. However, this hypothesis has to be verified, for example by using PCR MP technique. RESULTS: Methicillin-resistance was demonstrated in 24 out of 50 S. aureus isolates. Most MRSA strains (19 out of 24) presented multidrugresistance. Twelve various profiles of enzymatic activity and fifteen different genotypes (A-O) were singled out among the investigated strains. Profile A, recorded in 20 strains, was most frequent (Dice Coefficient: 0.80-0.94). CONCLUSIONS: 1. S. aureus strains present high resistance to antibiotics frequently showing multidrug-resistance coupled with methicillin-resistance 2. Genetically related MRSA strains present a stable drug-resistance pattern 3. Clonal transmission of MRSA strain was observed in two operative wards 4. The disc-diffusion method for testing antibiotic-resistance and PCR MP technique are useful in epidemiological investigation for S. aureus.

Search for drugs of the combined anti-inflammatory and anti-bacterial properties: 1-methyl-N'-(hydroxymethyl)nicotinamide.

It has already been reported that 1-methylnicotinamide (MNA+), a primary metabolite of nicotinamide (vitamin B3), possesses remarkable anti-inflammatory properties [3]. This communication shows that 1-methyl-N'-(hydroxymethyl)nicotinamide (MNAF+ can be regarded as MNA+ precursor able to release simultaneously formaldehyde. Therefore, MNAF+ can be viewed as a candidate for drug with the combined anti-inflammatory and anti-bacterial properties.

[The chosen aspects of hospital infections]. / Wybrane aspekty zakazen szpitalnych.

The paper presents some basic data on hospital infections and their influence in evaluation of hospital functioning. The most common infections, microorganism which are the cause of them, the role of patient immunological state, ways of spreading infections and ways of preventing them have been presented.

[Modern aspects of bioterrorism]. / Wspólczesne zagadnienia bioterroryzmu.

The study includes a survey of issues connected with the possibility of micro-organisms use in bioterrorist attack. The attention was drawn to the need of society co-operation in nuclear, chemical and biological weapons use prevention. The fundamental importance is a quick diagnosis, skills of undertaking preventive activities, treatment intending to save a great number of human beings.

[Health economics, medical ethics, and evidence-based medicine]. / Ekonomika zdrowia, etyka medyczna a medycyna oparta na dowodach naukowych.

The paper is based on the assumption that the management on different levels of decision-making requires not only strictly medical knowledge, but also the competence to make use of the acquisitions of health economics as well as certain knowledge of the principles of medical ethics and research methods applied in the evidence-based medicine. So far the relevant scientific literature lacks any attempts to analyse the common and separate features of the three fields mentioned above. Therefore, this paper aims at filling this gap. The objective is going to be met by acquainting the reader with the historical development of the three disciplines. Emphasis will be put on the existing definitions and scope of the health economics, medical ethics and evidence-based medicine. The concluding remarks contain the authors' conviction that this paper will contribute to make the medical environment more interested in the presented issues and thus constitute the first step to work out solutions which could be applied in clinical practice in the future.