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Nicholas J Legakis

Publications and source records attributed to Nicholas J Legakis.

12 recordsLinked to original sources
PubMed2006

The first database comprised of flagellin gene (flaA) types of Campylobacter jejuni human clinical isolates from Greece.

BACKGROUND: Flagellin subunit A gene (flaA) typing of Campylobacter has been recognized by several groups as a relatively simple and quick genotyping method. The present study aimed to create, for the first time in Greece, a database with flaA restriction patterns, which could be used for future epidemiological and clinical studies. A total of 207 C. jejuni clinical isolates of known serotype were collected from 5 general hospitals of the area of Attica, during the period 2000-2003. RESULTS: The RFLP profiles of each strain were matched in 44 bins of 0 or 1. Thirty nine different flaA types, designated as flaA 1 GR to flaA 39 GR (GR: Greece) were found. There was no significant association of certain genotypes with certain serotypes. However flaA typing showed a remarkable discriminatory ability inside the non-typable (NT) group. CONCLUSIONS: Evaluating our results we observed (i) that there was no clonality of a certain flaA type among the strains and the serotypes examined and (ii) that the discriminatory ability of flaA typing was much better than that of serotyping. Giving a simple and detailed description of the data analysis, we are the first who publish the bin patterns for the flaA genotypes found.

Bacterial Typing Techniques↗
PubMed2006

In vitro activities of tigecycline against recently isolated Gram-negative anaerobic bacteria in Greece, including metronidazole-resistant strains.

The in vitro activity of tigecycline was compared with those of benzylpenicillin, piperacillin + tazobactam, cefoxitin, imipenem, metronidazole, clindamycin, and tetracycline against 249 Gram-negative anaerobic bacteria (158 Bacteroides fragilis group, 27 non-fragilis Bacteroides spp., 44 Prevotella spp., and 20 miscellaneous), recently isolated from 8 general hospitals in Athens, Greece. Overall tigecycline MIC(50) and MIC(90) were 0.25 and 2 mg/L, respectively, whereas B. fragilis group MIC(50) and MIC(90) were 0.5 and 4 mg/L, respectively. In total, 93% of the isolates were susceptible to tigecycline (MIC </= 4 mg/L) and no high-level resistance (MIC >/= 32 mg/L) was detected. In addition, tigecycline exhibited good activity against metronidazole- and tetracycline-resistant isolates (MIC(90), 0.5 and 8 mg/L, respectively). In summary, tigecycline exhibits good in vitro activity against Gram-negative anaerobic bacteria isolated in Greece, as well as stability to the most common occurring resistance mechanisms, attributes that make this parenteral agent an attractive alternative for use against infections involving these microorganisms.

Anti-Bacterial Agents↗
PubMed2006

Frequent detection of cytomegalovirus in the intestine of patients with inflammatory bowel disease.

BACKGROUND: Although a growing number of reports have described inflammatory bowel disease (IBD) complicated with cytomegalovirus (CMV) infection, there are limited molecular studies that investigate CMV genome in intestinal sections of patients with IBD. METHODS: A cross-sectional prospective study was conducted between September 2000 and June 2003 in a cohort of 85 patients diagnosed with IBD (58 with ulcerative colitis and 27 with Crohn's disease) in two adult gastrointestinal referral centers in Athens, Greece. Prevalence of CMV infection was estimated by pathologic studies in intestinal sections and by molecular assays in blood and intestinal tissue samples and compared with a control group of 42 individuals with noninflammatory disease. RESULTS: Immunohistochemical staining showed CMV antigen in 10 IBD patients (7 with ulcerative colitis; 9 with severe disease), whereas CMV antigen was not detected in any of the controls. CMV genome in both the intestinal tissue and blood was found by polymerase chain reaction in 23 (27.1%) of the total IBD patients, in 18 (31.0%) of those with ulcerative colitis, and in 5 (18.5%) of those with Crohn's disease. In addition, five (5.9%) IBD patients (2 with ulcerative colitis and 3 with Crohn's disease) had detectable CMV genome in their intestinal samples but not in their blood. In the control group, five (11.9%) individuals had detectable CMV genome in their blood, but only one (2.2%) in his intestine. CONCLUSION: Patients with ulcerative colitis had more often detectable CMV genome in their blood as well as in their intestinal tissue samples as compared with controls (P = 0.022 and P < 0.0001, respectively). However, patients with Crohn's disease had more often detectable CMV genome only in their intestinal tissue samples as compared with controls (P = 0.001). Detection of CMV genome in blood or intestinal tissue was significantly associated with short duration of IBD (P = 0.0088 and 0.04, respectively) but not with age, sex, severity of the disease, activity at colonoscopy, pancolitis, administration of a specific treatment, and surgery. In this cross-sectional prospective study, detection of CMV genome or antigen in the intestine was commonly associated with IBD.

Adolescent↗
PubMed2006

Frequency and predictors of colonization of the respiratory tract by VIM-2-producing Pseudomonas aeruginosa in patients of a newly established intensive care unit.

The aim of this study was to examine the frequency and predictors of colonization of the respiratory tract by metallo-beta-lactamase (MBL)-producing Gram-negative bacteria in patients admitted to a newly established intensive care unit (ICU) of a tertiary care hospital. Specimens of tracheobronchial aspirates for microbiological studies were obtained every day for the first 3 days of the ICU stay and subsequently every third day for the rest of the ICU stay. PCR analysis and nucleotide sequencing were performed to identify bacteria that had MBL genes. Thirty-five patients (20 male, 15 female) were hospitalized during the initial 3 month period of functioning of the ICU. Colonization of the lower respiratory tract by Gram-negative bacteria was found in 29 of 35 patients (83 %) during the first 6-20 days (median 13 days) following admission to the ICU (13 patients with Acinetobacter baumannii, ten with Pseudomonas aeruginosa, three with Enterobacter aerogenes, two with Klebsiella pneumoniae and one with Stenotrophomonas maltophilia). Six of 29 patients (21 %) colonized with Gram-negative bacteria had bla(VIM-2)-positive P. aeruginosa isolates; one of these patients developed clinical infection due to this micro-organism. Previous use of carbapenems (P=0.01) or other beta-lactams (P=0.03), as well as a stay in the ICU of >20 days (P<0.001), were associated with colonization with bla(VIM-2)-producing P. aeruginosa. In conclusion, colonization by Gram-negative bacteria of the respiratory tract of patients in this newly established ICU was common (83 %). Use of beta-lactams, including carbapenems, was associated with subsequent colonization of the respiratory tract with MBL-positive P. aeruginosa.

Acute Disease↗
PubMed2006

Prevalence of infection by HTLV-I/II among pregnant women and high-risk groups in the Peloponnese peninsula, Greece.

Although screening for human T-cell lymphotropic virus types I and II (HTLV-I/II) antibodies in volunteer blood donors has been systematic in Greece since 1995, the epidemiology and the determinants of HTLV-I/II infection are not well defined among population groups. During 1997-2005, the prevalence of HTLV-I/II infection was investigated in a sample of 2016 pregnant women, 102 multitransfused haematologic and oncologic patients, 93 thalassaemic patients and 57 intravenous drug users originating from four geographic areas of Pelopennese peninsula, Greece. One recipient of HTLV-I infected blood and the relatives of a woman died from adult T-cell leukaemia/lymphoma (ATTL) related to HTLV-I have also been tested. The subjects were initially screened by an enzyme immunoassay whereas Western blot, INNO-LIA HTLV, polymerase chain reaction and nucleotide sequencing confirmed the infection. One thalassaemic patient had proved HTLV-I infection giving an overall prevalence of 11 per 1000. In the recipient of the infected blood and in two of the five relatives of the woman died from ATTL, HTLV-I infection was also detected. In none of the pregnant women, multitransfused patients and intravenous drug users HTLV-I/II infection was confirmed. These data suggest that HTLV-I is present in Greece among populations at high-risk. However, they would not support the need for HTLV-I/II antenatal screening in Greece.

Blotting, Western↗
PubMed2006

VIM-1 metallo-beta-lactamase in Acinetobacter baumannii.

In 2004 and 2005, 5 metallo-beta-lactamase (MBL)-positive Acinetobacter baumannii isolates were found in 2 Greek hospitals. Isolates were unrelated and carried blaVIM-1 in a class 1 integron; bla(OXA-51-) and bla(OXA-58-like) carbapenemase genes were also detected. VIM-1 MBL in Acinetobacter spp. causes concern, given the increasing resistance of this species.

Acinetobacter Infections↗
PubMed2005

VIM-12, a novel plasmid-mediated metallo-beta-lactamase from Klebsiella pneumoniae that resembles a VIM-1/VIM-2 hybrid.

A transferable plasmid from Klebsiella pneumoniae carried a class 1 integron containing bla(VIM-12), a novel bla(VIM)-type gene, flanked by two copies of aacA7. bla(VIM-12) was clustered between bla(VIM-1) and bla(VIM-2) and differed from bla(VIM-1) by 18 nucleotides that were all located at the 3' end and matched the corresponding nucleotides in bla(VIM-2). The bla(VIM-12)-associated 59-base element was identical to that described in bla(VIM-2) alleles.

Alleles↗
PubMed2004

Ruling out Bacillus anthracis.

Optimization of methods for ruling out Bacillus anthracis leads to increased yields, faster turnaround times, and a lighter workload. We used 72 environmental non-B. anthracis bacilli to validate methods for ruling out B. anthracis. Most effective were the use of horse blood agar, motility testing after isolates had a 2-h incubation in trypticase soy broth, and screening isolates with a B. anthracis-selective agar.

Animals↗
PubMed2003

Prevalence and characterization of the mechanisms of macrolide, lincosamide and streptogramin resistance in viridans group streptococci.

The presence of erm genes conferring constitutive and inducible resistance, as well as that of the mefA gene conferring only constitutive resistance, was investigated using PCR in 70 erythromycin resistant (MIC>or=1 mg/l) strains of viridans group streptococci (VGS) (18 Streptococcus mitis biotype 1, 16 S. mitis biotype 2, 15 S. oralis, 12 S. salivarius and nine S. sanguis) isolated from the oropharynx of healthy Greek children. All of the 56 isolates belonging to resistance phenotype M harbored the mefA gene. All of the 14 isolates constitutively resistant to macrolides and lincosamides (phenotype CR) harbored the ermB gene. Co-presence of both genes was not observed, whereas class A erm gene (previously known as ermTR) was not detected. Our results are consistent with a possible role of VGS as a reservoir of resistance genes now prevalent in pathogenic species of streptococci.

Anti-Bacterial Agents↗
PubMed2002

Epidemiology of multiresistant Enterococcus avium isolates in a Greek tertiary care hospital.

A retrospective survey of the isolation rate of Enterococcus avium during the period March 1994-February 2000 conducted in Laikon General Hospital using the WHONET software, revealed a peak in the isolation rates of this species during March 1995-February 1996. The ten strains isolated during this time were studied further. No glycopeptide resistance was detected but resistance to ampicillin, ciprofloxacin, erythromycin, gentamicin (high-level) and streptomycin (high-level) was present in nine, ten, nine, three and seven of the isolates, respectively. The genes aac(6')-Ie+aph(2")-Ia and ant(6)-I, encoding for high-level gentamicin and streptomycin resistance, respectively, were detected only in the isolates with the corresponding phenotypes. Beta-lactamase production and haemolysis were not detected. There was evidence of ward-, floor- and building-specific distribution among the different aminoglycoside resistance phenotypes. DNA fingerprinting by PFGE grouped six of the ten isolates in a single cluster with 83% similarity, even though they expressed various resistance phenotypes. These results suggest dissemination of resistance genes among both genetically related and unrelated strains.

Anti-Bacterial Agents↗