PubMed Health⌕ Search

Biomedical subjects

E Nagy

Publications and source records attributed to E Nagy.

At least 19 recordsLinked to original sources

Design of a single tube RT-PCR assay for the diagnosis of human infection with highly pathogenic influenza A(H5) viruses.

Concerns about emergence of a pandemic strain of influenza have been increasing. The strains of highly pathogenic influenza A(H5N1) currently circulating are considered among the most plausible candidates for giving rise to a pandemic strain. In this study the design and development of a RT-PCR assay specific for these highly pathogenic influenza A(H5) strains is presented. This is achieved in part by the design of a primer targeting the coding region for the protease cleavage site of the hemagglutinin, and another primer derived from a pan-hemagglutinin RT-PCR assay also presented in this study. It is shown that the HPAI A(H5) specific assay amplifies only the nucleic acids of highly pathogenic A(H5), with a high sensitivity.

Animals↗

Examination of cfiA-mediated carbapenem resistance in Bacteroides fragilis strains from a European antibiotic susceptibility survey.

Of 1284 Bacteroides strains collected in Europe in 2000 for antibiotic susceptibility surveillance, 65 isolates displayed imipenem minimum inhibitory concentrations (MICs) > or =1 mg/L and were chosen for a thorough analysis of their resistance mechanism. Twenty-five of the isolates were positive for the cfiA carbapenem resistance gene. The resistance rates were 0.8% and 1.3% for imipenem and meropenem, respectively. In six of the strains, insertion sequence (IS) elements (IS613, IS614B, IS1186 and IS1187) activated the cfiA gene. However, other strains displayed at least elevated carbapenem MICs or were carbapenem resistant and produced measurable carbapenemase activities but did not harbour IS elements in the region upstream of the cfiA gene. The major determinant of carbapenem resistance in Bacteroides fragilis is production of CfiA metallo-beta-lactamase via activation of the cfiA gene by IS elements (higher level resistance) or by activation of its putative own promoter.

Anti-Bacterial Agents↗

The role of biofilm infection in urology.

In the process of endourological development a great variety of foreign bodies have been invented besides urinary catheters on which biofilm can be formed. Bacteria in the biofilm are less sensible to antibiotics. An additional problem of medical biomaterials in the urinary tract environment is the development of encrustation and consecutive obstruction. In this review, we tried to sum up the conditions where biofilm formation has a great impact on the development or maintenance of urological infections and on treatment success. Modification of the biomaterial surface seems to be the most promising prevention strategy for bacterial biofilms. Easier methods for diagnosing and quantifying biofilm infection, to develop more specific antimicrobial agents and ideal device surfaces would surely help the fight against biofilm formation.

Anti-Bacterial Agents↗

Sequence analysis of the left end of fowl adenovirus genomes.

Nucleotide sequence analysis of the left end of the genome of fowl adenoviruses (FAdV) representing species group C (FAdV-4 and -10), D (FAdV-2) and E (FAdV-8) were carried out, and the sequence data was compared to those of FAdV-1 (FAdV-A) and FAdV-9 (FAdV-D). The viruses were propagated in chicken hepatoma cell line for viral DNA isolation. Restriction endonuclease analysis was performed followed by hybridization with two DNA probes representing the left end of FAdV-9. The identified fragments were sequenced, and the generated data were compared with the GenBank database. Nucleotide sequence homology and amino acid sequence identities were high between members of the same species group, FAdV-2 and -9, and FAdV-4 and -10, whereas different degrees of variations were observed among all FAdVs. Gene arrangement and position of ORFs at the left end of FAdV genomes were largely conserved suggesting similar gene functions. All previously characterized left end ORFs in CELO virus and FAdV-9 were found in all analyzed FAdVs. However, ORF 1C was absent in FAdV-4 and -10, but additional ORFs, most likely corresponding to duplicates of ORF 14, were observed in these viruses.

Amino Acid Sequence↗

Hemodialysis reduces inhibitory effect of plasma ultrafiltrate on LDL oxidation and subsequent endothelial reactions.

Oxidative modification of low-density lipoprotein (LDL) and its deleterious effect on endothelium is implicated in the pathogenesis of atherosclerosis. Endothelium responds to such an insult by upregulating the synthesis of heme oxygenase-1 (HO-1) and ferritin. Endothelial cell damage and dysfunction have been observed in patients with chronic kidney disease (CKD) on maintenance hemodialysis (HD). We studied the effect of low-molecular-weight components of uremic plasma on LDL oxidation and LDL-oxidation-provoked endothelial cell reactions, such as the induction of cytotoxicity and the upregulation of cell-protective HO-1 and ferritin. Plasma ultrafiltrate (molecular weight<5000 Da) from CKD patients on HD or when treated conservatively exhibited a pronounced inhibition on heme-mediated oxidative modification of LDL. Endothelial cell cytotoxicity provoked by LDL oxidation was also attenuated by plasma ultrafiltrate from CKD patients. During HD treatment, a dramatic drop occurred in the retardation of oxidative reactions, and a loss of endothelial cytoprotection exerted by plasma ultrafiltrate was noted. The upregulation of HO-1 and ferritin in response to oxidative stress of LDL was blunted by uremic plasma ultrafiltrate that was released by the end of HD. The decreased antioxidant capacity of ultrafiltrate after HD occurred as a consequence of the intradialytic removal of L-ascorbic acid, uric acid, bilirubin, 3-indoxyl sulfate, indoxyl-beta-D-glucuronide, p-cresol, and phenol. Intradialytic removal of L-ascorbic acid, uric acid, bilirubin, 3-indoxyl sulfate, indoxyl-beta-D-glucuronide, p-cresol, and phenol increases the risk of LDL oxidation and subsequent endothelial cell damage, which underlines the importance of activation of cytoprotective HO-1 and ferritin in endothelium.

Adult↗

Rapid identification of clinical Trichoderma longibrachiatum isolates by cellulose-acetate electrophoresis-mediated isoenzyme analysis.

Cellulose-acetate electrophoresis was used to investigate isoenzyme polymorphism among ten clinical and 11 non-clinical isolates of Trichoderma. Initial testing of 13 enzyme systems for activity and resolution of bands showed that seven were appropriate for identifying the different species. Each of the enzyme systems investigated (glucose-6-phosphate dehydrogenase, glucose-6-phosphate isomerase, 6-phosphogluconate dehydrogenase, peptidases A, B and D, and phosphoglucomutase) was diagnostic for at least one species. On the basis of the results of isoenzyme analysis, several isolates identified originally as Trichoderma pseudokoningii, T. koningii or T. citrinoviride were re-identified as T. longibrachiatum, in agreement with sequence analysis data for the internal transcribed spacer region of the isolates. The availability of a quick, inexpensive and reliable diagnostic tool for the identification of T. longibrachiatum isolates is important, as most clinical Trichoderma isolates belong to T. longibrachiatum. Furthermore, as many different enzyme systems are available, the method may also be suitable for the identification of other clinically relevant fungal species.

Electrophoresis, Cellulose Acetate↗

Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis.

CONTEXT: Plasma fibrinogen levels may be associated with the risk of coronary heart disease (CHD) and stroke. OBJECTIVE: To assess the relationships of fibrinogen levels with risk of major vascular and with risk of nonvascular outcomes based on individual participant data. DATA SOURCES: Relevant studies were identified by computer-assisted searches, hand searches of reference lists, and personal communication with relevant investigators. STUDY SELECTION: All identified prospective studies were included with information available on baseline fibrinogen levels and details of subsequent major vascular morbidity and/or cause-specific mortality during at least 1 year of follow-up. Studies were excluded if they recruited participants on the basis of having had a previous history of cardiovascular disease; participants with known preexisting CHD or stroke were excluded. DATA EXTRACTION: Individual records were provided on each of 154,211 participants in 31 prospective studies. During 1.38 million person-years of follow-up, there were 6944 first nonfatal myocardial infarctions or stroke events and 13,210 deaths. Cause-specific mortality was generally available. Analyses involved proportional hazards modeling with adjustment for confounding by known cardiovascular risk factors and for regression dilution bias. DATA SYNTHESIS: Within each age group considered (40-59, 60-69, and > or =70 years), there was an approximately log-linear association with usual fibrinogen level for the risk of any CHD, any stroke, other vascular (eg, non-CHD, nonstroke) mortality, and nonvascular mortality. There was no evidence of a threshold within the range of usual fibrinogen level studied at any age. The age- and sex- adjusted hazard ratio per 1-g/L increase in usual fibrinogen level for CHD was 2.42 (95% confidence interval [CI], 2.24-2.60); stroke, 2.06 (95% CI, 1.83-2.33); other vascular mortality, 2.76 (95% CI, 2.28-3.35); and nonvascular mortality, 2.03 (95% CI, 1.90-2.18). The hazard ratios for CHD and stroke were reduced to about 1.8 after further adjustment for measured values of several established vascular risk factors. In a subset of 7011 participants with available C-reactive protein values, the findings for CHD were essentially unchanged following additional adjustment for C-reactive protein. The associations of fibrinogen level with CHD or stroke did not differ substantially according to sex, smoking, blood pressure, blood lipid levels, or several features of study design. CONCLUSIONS: In this large individual participant meta-analysis, moderately strong associations were found between usual plasma fibrinogen level and the risks of CHD, stroke, other vascular mortality, and nonvascular mortality in a wide range of circumstances in healthy middle-aged adults. Assessment of any causal relevance of elevated fibrinogen levels to disease requires additional research.

Adult↗

Oxidation of hemoglobin by lipid hydroperoxide associated with low-density lipoprotein (LDL) and increased cytotoxic effect by LDL oxidation in heme oxygenase-1 (HO-1) deficiency.

Heme-catalyzed oxidation of low-density lipoprotein (LDL) is one of the relevant mechanisms involved in LDL modification. We previously revealed a substantial oxidation of plasma hemoglobin to methemoglobin and a subsequent heme-catalyzed LDL oxidation generating moieties toxic to endothelium in heme oxygenase-1 (HO-1)-deficiency in human. Drawing upon our previous observation we posited a pathway for oxidation of plasma hemoglobin in the HO-1-deficient child involving LDL-associated lipid hydroperoxide. In support, LDL-associated lipid hydroperoxide oxidized ferrohemoglobin to methemoglobin--known to readily release its heme moieties--in a dose-dependent manner. Repeated heme exposure of the child s LDL further increased its lipid hydroperoxide content within min leading to additional cytotoxic effect on endothelium. Both cytotoxicity and HO-1 inducing ability of the oxidized LDL were strongly dependent on its lipid hydroperoxide content. We wondered if cells of the HO-1-deficient patient were prone to oxidative damage arising from heme-mediated oxidation of LDL. Indeed, we found elevated cytotoxicity induced by heme-catalyzed oxidation of LDL in lymphoblastoid cells derived from the HO-1-deficient patient. We conclude that oxidation of hemoglobin to methemoglobin by LDL-associated lipid hydroperoxide and increased sensitivity of cells of the HO-1-deficient child to stress of oxidized LDL might contribute to the vascular disorders reported earlier.

Cell Proliferation↗

Structure prerequisite for antioxidant activity of silybin in different biochemical systems in vitro.

Structural analogues (flavanone: 2-4 and flavone: 5 and 6, respectively) of silybin (1a) were synthesized and tested for inhibitory activity on O(2)(-) release and PKC translocation in PMA-stimulated neutrophils as well as xanthine oxidase activity in order to identify the molecular structures responsible for the antioxidant property of silybin. Concerning the prevention of hem-mediated oxidative modification of LDL by silybin, the hydroxyl radical scavenging activity of its structural analogues was also determined. We demonstrated that the basic skeleton of 1a (4) is responsible for its inhibitory activity on O(2)(-) release in PMA-stimulated neutrophils via inhibition of PKC translocation, since introduction of a double bound and hydroxyl groups at C-5 and C-7 position (5 and 6) did not result in further increase in inhibition of O(2)(-) release. It has been shown that the presence of the phenolic hydroxyl group at C-5 and C-7 of 1a is essential for the inhibition of xanthine oxidase activity. Moreover, introduction of a double bond into the C-ring of 2 and 3, resulting in flavone derivatives (5 and 6), markedly enhanced the antioxidant effect in all the tested systems. Finally, silybin (1a) and its flavon derivatives (5 and 6) directly scavenged hydroxyl radicals as well. On the basis of these results it might be concluded that different moiety of silybin is responsible for inhibition of overproduction of O(2)(-) in stimulated neutrophils, xanthine oxidase activity, and for prevention of hem-mediated oxidative modification of LDL.

Antioxidants↗

Agrobacterium tumefaciens-mediated transformation of Mucor circinelloides.

The Agrobacterium tumefaciens-mediated transformation of the zygomycetous fungus Mucor circinelloides is described. A method was also developed for the hygromycin B-based selection of Mucor transformants. Transformation with the hygromycin B phosphotransferase gene of Escherichia coli controlled by the heterologous Aspergillus nidulans trpC promoter resulted in hygromycin B-resistant clones. The presence of the hygromycin resistance gene in the genome of the transformants was verified by polymerase chain reaction and Southern hybridization: the latter analyses revealed integrations in the host genome at different sites in different transformants. The stability of transformants remained questionable during the latter analyses.

Agrobacterium tumefaciens↗

Biofilm formation on intrauterine devices in relation to duration of use.

Intrauterine devices (IUDs) are highly effective, long-term methods of contraception; however, IUD use is limited due to concerns about an increased risk of pelvic inflammatory disease (PID) and subsequent complications. A retrospective review of clinical and microbiological data of 127 participants was carried out over a 3 year period. IUDs were removed and sent for microbiological examination. A 10 year old IUD, removed because of the symptoms of PID, was investigated via both microbial culture and scanning electron microscopy. The primary objective of this study was to examine the bacteria present on removed IUDs after different times in situ by using aerobic and anaerobic culture methods. A close association of the distribution of aerobic and anaerobic bacteria on the IUDs with different times in situ was found.

Bacteria, Aerobic↗

The training curriculum in hospital infection control.

Standardised training curricula for infection control nurses (ICNs) and recognition of the specialty exist in many European countries, but infection control physician (ICP) is not a specialty recognised by the UEMS. To gather information on curricula for ICPs, members of the ESCMID Study Group on Nosocomial Infections received a questionnaire. There is discussion about which 'professions' should be included in an infection control team. Within the 12 countries included, the average full-time equivalents (FTEs) for ICPs and ICNs per 1000 beds were 1.2 and 3.4, respectively. In addition to ICNs and ICPs, an infection control team should also include a data manager, an epidemiologist, secretarial/administrative support, and possibly, surveillance technicians. Overall, the composition of an ideal infection control team was estimated to be 9.3 FTE per 1000 beds. The background of ICPs can be clinical microbiology or infectious diseases. Among the participants, it was predominantly clinical microbiology. The ideal training curriculum for the ICP should include 6 years of postgraduate training. Of these, at least 2 years should be 'clinical training' (e.g., internal medicine) to acquire experience in the management of high-risk patients. Furthermore, training with regard to infection control and hospital epidemiology should be offered as a 'common trunk' for those being trained in clinical microbiology or infectious diseases. Important issues that remain are: implementation/standardisation of training curricula for doctors, recognition of ICP as a separate specialty or sub-specialty of clinical microbiology and/or infectious diseases, validation of on-the-job training facilities in terms of the number of doctors and nurses who can give training and the category of patients/problems present, and mandatory postgraduate education/continuing medical education specific for infection control for doctors and nurses in the field.

Cross Infection↗

The relationship between serotypes and PFGE genotypes in isolates of Streptococcus pneumoniae from Hungary.

The relatedness of 112 penicillin-non-susceptible isolates of Streptococcus pneumoniae from Hungary was determined by pulsed-field gel electrophoresis (PFGE), serotyping and antibiotic susceptibility tests. The differences in PFGE patterns closely mirrored the changes in resistance. Some genotypes comprised multiple serotypes, and the genetic diversity among certain serotypes was considerable. Generally, serotyping alone was insufficient for epidemiological mapping of pneumococcal isolates. There was considerable serotype diversity, but the five most frequent international serotypes (6, 9, 14, 23, 19) were the most prevalent. In addition, the presence of some well-defined resistant international pneumococcal clones in the Hungarian population was identified.

Anti-Bacterial Agents↗

Results from the ARTEMIS DISK Global Antifungal Surveillance Study: a 6.5-year analysis of susceptibilities of Candida and other yeast species to fluconazole and voriconazole by standardized disk diffusion testing.

Fluconazole in vitro susceptibility test results for 140,767 yeasts were collected from 127 participating investigators in 39 countries from June 1997 through December 2003. Data were collected on 79,343 yeast isolates tested with voriconazole from 2001 through 2003. All investigators tested clinical yeast isolates by the CLSI (formerly NCCLS) M44-A disk diffusion method. Test plates were automatically read and results were recorded with the BIOMIC Vision Image Analysis System. Species, drug, zone diameter, susceptibility category, and quality control results were collected quarterly via e-mail for analysis. Duplicate (the same patient, same species, and same susceptible-resistant biotype profile during any 7-day period) and uncontrolled test results were not analyzed. The 10 most common species of yeasts all showed less resistance to voriconazole than to fluconazole. Candida krusei showed the largest difference, with over 70% resistance to fluconazole and less than 8% to voriconazole. All species of yeasts tested were more susceptible to voriconazole than to fluconazole, assuming proposed interpretive breakpoints of > or =17 mm (susceptible) and < or =13 mm (resistant) for voriconazole. MICs reported in this study were determined from the zone diameter in millimeters from the continuous agar gradient around each disk, which was calibrated with MICs determined from the standard CLSI M27-A2 broth dilution method by balanced-weight regression analysis. The results from this investigation demonstrate the broad spectrum of the azoles for most of the opportunistic yeast pathogens but also highlight several areas where resistance may be progressing and/or where previously rare species may be "emerging."

Antifungal Agents↗

In vitro and in vivo percutaneous absorption of topical dosage forms: case studies.

This article evaluated the influence of vehicle compositions on topical drug availability. In vitro drug release and in vivo experiments were performed in case of the hydrophilic ketamine hydrochloride and the lipophilic piroxicam. Ketamine hydrochloride is a NMDA receptor antagonist that has been useful for anesthesia and analgesia. The study of transdermal ketamine delivery is a novelty, because nobody has investigated the hypnotic effects of ketamine after this administration route. In vitro measurements gave a good basis for screening among the developed products. The physiological changes after ketamine administration showed, that there were significant differences among the parameters tested (breathing rate, duration of sleep) from the developed products (hydrogel, lyotropic liquid crystal and o/w cream) compared to the reference product (Carbopol gel). The in vivo feedback for piroxicam was the measurement of the anti-inflammatory activity by edema inhibition percentage. Significant differences were measured in case of the developed systems compared to the reference.

Administration, Cutaneous↗

In vitro water activity and pH dependence of mycelial growth and extracellular enzyme activities of Trichoderma strains with biocontrol potential.

AIMS: Water activity (aw) and pH are probably the most important environmental parameters affecting the activities of mycoparasitic Trichoderma strains. Therefore it is important to collect information on the effects of these factors on mycelial growth and on the in vitro activities of extracellular enzymes involved in nutrient competition (e.g. beta-glucosidase, cellobiohydrolase and beta-xylosidase) and mycoparasitism (e.g. N-acetyl-beta-glucosaminidase, trypsin-like protease and chymotrypsin-like protease) of Trichoderma strains with biocontrol potential. METHODS AND RESULTS: Water activity and pH dependence of the linear mycelial growth of five examined Trichoderma strains belonging to three different species groups was examined on yeast extract and soil extract media. Maximal growth rates were observed at aw 0.997 and pH 4.0 in the case of all strains. The activities of the examined extracellular enzymes at different aw and pH values were determined spectrophotometrically after incubation with chromogenic p-nitrophenyl and p-nitroaniline substrates. Maximal enzyme activities were measured at aw 0.950 for beta-glucosidase, trypsin-like protease and chymotrypsin-like protease, at 0.910 for cellobiohydrolase and at 0.993 for beta-xylosidase and N-acetyl-beta-glucosaminidase enzymes. Optimal pH values are suggested to be at 5.0 for beta-glucosidase, cellobiohydrolase and N-acetyl-beta-glucosaminidase, at 3.0 for beta-xylosidase, at 6.0 for trypsin-like protease and between 6.0 and 7.0 for chymotrypsin-like protease activities, respectively. CONCLUSIONS: Extracellular enzymes of the examined mycoparasitic Trichoderma strains are able to display activities under a wider range of aw and pH values than those allowing mycelial growth. SIGNIFICANCE AND IMPACT OF THE STUDY: Data about the effects of aw and pH on mycelial growth and extracellular enzyme activities of Trichoderma reveal useful information about the applicability of biocontrol strains in agricultural soils with specific water and pH relations.

Biodegradation, Environmental↗

Involvement of Fusarium spp. in fungal keratitis.

Members of the filamentous fungal genus Fusarium are among the agents most frequently causing keratomycosis in humans. Fusarium keratitis is most common among agricultural workers in geographical regions with hot, humid, tropical or semi-tropical climates, but can occur more rarely in countries with temperate climates, such as Hungary. Keratitis is usually treated with a topical antifungal agent, sometimes in combination with sub-conjunctival injections and/or antimycotic agents, but therapeutic keratoplasty may be needed for patients whose corneal infection does not resolve. Early and accurate diagnosis, coupled with appropriate antifungal therapy, is crucial for improving the chances of complete recovery.

Agricultural Workers' Diseases↗