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Telomerase is involved in the elongation of telomeres. It remains active in very few types of cell in mature organisms. One such cell type is the lymphocytes. In this study, we investigated the activity and expression of telomerase in lymphocytes from renal failure patients and compared it to that for normal controls. Inflammation status was determined at the same time. The enzyme activity was measured using PCR-ELISA with peripheral blood mononuclear cells (PBMCs) from three groups: 53 healthy individuals, 50 patients with chronic kidney disease (CKD) and 50 dialysis patients. In the same cell populations, the expression of the reverse transcriptase of the human telomerase gene (hTERT) was measured via real-time PCR. The inflammationstatus of these individuals was determined by calculating the interleukin 6 (IL-6), IL-10, C-reactive protein (CRP) and tumor necrosis factor alpha (TNF-a) serum concentrations via ELISA. The lowest levels of telomerase activity were detected in CKD, and this group had the highest IL-6 and CRP values and the lowest hTERT expression. The dialysis group showed significant differences in comparison to the normal subjects and to the CKD patients. Further studies are warranted in order to explore the way inflammation influences telomerase activity and hTERT expression.

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BACKGROUND: The molecular epidemiology of C. jejuni and C. coli clinical strains isolated from children with gastroenteritis, was investigated using the multilocus sequence typing method (MLST). This analysis establishes for the first time in Greece and constitutes an important tool for the epidemiological surveillance and control of Campylobacter infection in our country. METHODS: The MLST genotypes were compared with those gained by other typing methods (HS-typing, PFGE and FlaA typing) and were also phylogenetically analyzed, in order to uncover genetic relationships. RESULTS: Among 68 C. jejuni strains, 41 different MLST-Sequence Types (MLST-STs) were found. Fifty six strains or 34 MLST-STs could be sorted into 15 different MLST-Sequence Type Complexes (MLST-STCs), while twelve strains or seven MLST-STs did not match any of the MLST-STCs of the database. Twenty C. coli strains belonged to 14 different MLST-STs. Eleven MLST-STs were classified in the same MLST-STC (828), and three were unclassifiable. There was no significant association between the MLST-STs and the results of the other typing methods.Phylogenetic analysis revealed that some strains, classified to the species of C. jejuni, formed a separate, phylogenetically distinct group. In eight strains some alleles belonging to the taxonomic cluster of C. jejuni, were also detected in C. coli and vice versa, a phenomenon caused by the genetic mosaic encountered inside the genus Campylobacter. CONCLUSIONS: The MLST-ST determination proved to be a very useful tool for the typing as well as the identification of Campylobacter on the species level.

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Malaria has become an emerging infection in Greece, which is the doorstep to Europe for thousands of immigrants. With increasing immigration, cases with evidence of domestic transmission (autochthonous) are being reported. In the present study, an isolate of Plasmodium vivax from an autochthonous clinical case was subjected to phylogenetic analysis of the genes encoding the merozoite surface protein 1 (MSP-1) and the circumsporozoite protein (CSP). In the MSP region, the strain was related with strains from Brazil, South Korea, Turkey and Thailand, whereas in the CSP region, with strains from Brazil, Colombia and New Guinea. The present study establishes for the first time in Greece the basis for the creation of a database comprising genotypic and phylogenetic characteristics of Plasmodium spp.

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Patients suffering from renal failure exhibit an impaired immune system function. We wanted to investigate the transcription of the tumor suppressor genes p53 and RB to record, if these cells could be stimulated in vitro in order to divide, after the addition of antigenic and inflammatory factors. This expression was measured by real-time PCR in peripheral blood mononuclear cells (PBMCs) from three different groups: ten healthy individuals, ten patients with chronic kidney disease (CKD), and ten dialysis patients with end stage renal disease (ESRD). The transcription rate of these genes was also measured after the cultivation of PBMCs under four different conditions: just with the culture medium, with lipopolysaccharide (LPS), with C-reactive protein (CRP), and with lipoxin A(4) (LXA(4))-LPS. Our results show that in most cases after the cultivation with additives, the transcription levels were higher in dialysis patients compared to those of the other two groups. Our findings serve as indications of cellular senescence on a molecular level, while it seems that these cells are less easily stimulated in vitro in order to duplicate.

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BACKGROUND: Campylobacter spp. are together with Salmonella spp. the leading causes of human bacterial gastroenteritis worldwide. The most commonly isolated species in humans are Campylobacter jejuni and C. coli. The isolation, identification, and antimicrobial resistance of Campylobacter spp. from poultry and raw meat from slaughterhouses, has been investigated for the first time in Greece. During the period from August 2005 to November 2008 a total of 1080 samples were collected: (a) 830 fecal samples from five poultry farms, (b) 150 cecal samples from chicken carcasses in a slaughterhouse, and (c) 100 fecal samples from one pig farm near the region of Attica. The identification of the isolates was performed with conventional (sodium hippurate hydrolysis and commercial identification system (Api CAMPY system, bioMerieux, France), as well as with and molecular methods based on 16S rRNA species specific gene amplification by PCR and subsequent sequence analysis of the PCR products. RESULTS: Sixteen Campylobacter strains were isolated, all collected from the poultry farms. None of the strains was identified as C. jejuni. Antimicrobial susceptibility to six antimicrobials was performed and all the strains were susceptible to ciprofloxacin, amoxicillin-clavulanic acid, and gentamicin. Thirteen out of 14 C. coli were resistant to erythromycin and all C. coli strains were resistant to ampicillin. CONCLUSION: Our results emphasize the need for a surveillance and monitoring system with respect to the prevalence and antimicrobial resistance of Campylobacter in poultry, as well as for the use of antimicrobials in veterinary medicine in Greece.

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BACKGROUND/AIM: The need for sensitive biological markers to detect and prove recent drinking has been the focus of many research groups. The aim of our study was to investigate the alterations of biological markers in a population of alcohol dependent individuals during the detoxification period. PATIENTS AND METHODS: Fifty-two alcohol-dependent individuals were admitted for alcohol detoxification on an inpatient basis. Carbohydrate-deficient transferrin (CDT), gamma-glutamyl transpeptidase (gamma-GT), interleukin-6 (IL-6), mean corpuscular volume (MCV), aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) were obtained at admission and on a 15-day basis. Comparisons between measures were made with t-test. RESULTS: All biochemical parameters associated with alcoholism, with the exception of MCV, were statistically significantly decreased during the detoxification process (p<0.05). CONCLUSION: CDT is an excellent marker of alcohol overconsumption during evaluation, as well as during the detoxification treatment. IL-6 could serve as an additional marker to CDT, a point needing further investigation.

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The distribution of Yersinia strains in animal reservoirs was examined in 835 food animals (pigs, chickens, sheep, cows) from different Greek departments (Attica, Fthiotida, Viotia and Evia) over a one year period. The isolated strains were characterized with respect to the presence of chromosomal (yst) and plasmid-encoded virulence determinants (virF, yadA) and their antimicrobial susceptibility was tested. In total, Yersiniaspp. were obtained from 9.94% of the 835 food animals at slaughter that were sampled in this study. There was no statistically significant seasonal distribution, nor was any significant departmental distribution observed. From the 83 isolated Yersinia strains, 76 (91,57%) belonged to Y. enterocolitica (58 were of serotype O:3/biotype 4 and 18 strains were non O:3, non O:9), 3 belonged to Y. pseudotuberculosis, 2 to Y. kristensenii and 2 to Y. intermedia. Y. enterocolitica O:3/4 was mainly isolated from the pigs, while Y. enterocolitica non O:3, non O:9 was from the chickens. The strains were grouped into 5 genotypes, with respect to the presence or absence of the virulence genes. A significant predominance of genotype V, the one carrying all the three virulence genes, was observed in the strains isolated from the pigs. Complete susceptibility to most of the 3rd and to the 4th generation cephalosporins and to ciprofloxacin, was observed among the isolates. Remarkable was the association between the presence of each virulence gene separately and resistance to some antimicrobials, a matter of further investigation.

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Alcohol abuse is a major cause of liver cirrhosis as well as chronic liver disease. The aim of the present study was to investigate the possible correlation, between liver dysfunction biological markers and vitamin B12, with interleukin-6, in the serum of alcohol-dependent individuals without liver disease (AWLD). In a sample of 43 alcohol abusing/dependent subjects (33 males and 10 females) treated on an inpatient basis according to a standard detoxification protocol, the serum activities of the hepatic enzymes (ASAT, ALAT, gamma-GT), as well as the concentration of B12 and IL-6, were determined on admission. A strong positive correlation has been observed between IL-6 and B12, ASAT, ALAT, and gamma-GT at the beginning of the detoxification period. The results confirmed that in alcohol-dependent individuals, the median serum concentration of IL-6, before the beginning of the treatment, had a significant positive correlation with the liver dysfunction biological markers and B12. In conclusion, IL-6 might be used as an additional diagnostic marker for the degree of liver dysfunction in alcohol dependent individuals.

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BACKGROUND: Pulsed-field gel electrophoresis (PFGE) typing has been recognized by several groups as a relatively simple and quick method for genotyping of Campylobacter jejuni (C. jejuni). The present study was carried out to determine the genetic variations among clinical isolates of C. jejuni from Greece and to establish a database, which could be used for future epidemiological and clinical studies. METHODS: A total of 93 C. jejuni clinical isolates of known flagellin subunit A (flaA) genotype, serotype, and antimicrobial susceptibility pattern, were collected from a general hospital in the Attica region of Greece, between the years 2000 and 2003. The PFGE profiles of SmaI DNA digests of each strain were compared using a bin analysis based on 44 molecular size intervals. RESULTS: Forty-three different PFGE types, designated as C. jejuni (C. j.) 1 Greece (GR) to C. j. 43 GR, were identified. There was no statistically significant association of PFGE type with flaA genotype, serotype, or antimicrobial susceptibility pattern. However, PFGE typing did show a remarkable discriminatory ability within the non-serotypable group. CONCLUSION: Evaluating our results, we observed that (i) there was no statistically significant clonality of a certain PFGE type among the strains examined, and (ii) the discriminatory ability of PFGE typing was much better than that of the other typing methods. This is the first report of the use of bin patterns to compare the PFGE genotypes identified.

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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.

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INTRODUCTION: The presence of four virulence genes (racR, wlaN, cgtB, virB11) in 356 Campylobacter jejuni strains isolated from confirmed clinical cases was examined by PCR and sequence analysis. The investigated genes were chosen on the basis of their variation in prevalence. METHODS: The virulence genes were detected by PCR and the amplified products were submitted for sequence analysis. RESULTS: The gene with the highest prevalence was racR (87.08%). virB was present in only 1.69% of the C. jejuni strains, and wlaN and cgtB were detected in 16.01% and 24.44%, respectively. Five strains associated with Guillain-Barré syndrome and Miller-Fischer syndrome out of the total of 356 (1.40%) were positive for cgtB. CONCLUSION: Our findings suggest that racR may encode factors necessary for bacterial pathogenicity in humans, while the roles of the other three genes remain ambiguous.

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In the current study, our aim was to evaluate and investigate the influence of heavy alcohol intake on serum interleukin (IL)-6, IL-8, IL-10, IL-12, and tumor necrosis factor-alpha (TNF-alpha) concentrations. The selection of cytokines was based on their presumptive role in the pathophysiology of alcohol dependence. On admission to the Drug-Free Substance Addiction Detoxification clinic ("ATHENA"), blood samples were obtained from study participants, and serum cytokine concentrations were measured by using a commercial sandwich enzyme-linked immunosorbent assay technique. Alcohol dependence, as diagnosed according to DSM-IV [Diagnostic and Statistical Manual of Mental Disorders (4th ed.)] criteria for alcohol dependence and estimated by using the Composite International Diagnostic Interview (CIDI), was characterized by increased serum IL-6 concentration. Interleukin-8, IL-10, IL-12, and TNF-alpha concentrations were comparable to those found in control subjects (P>.05). These results indicate that in alcohol-dependent individuals there is a significant increase in the serum IL-6 concentration (P <.05).

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A hundred and twentynine Campylobacter jejuni strains isolated from hospitalized children with gastroenteritis were serotyped by the heat-stable antigen scheme (HS, Penner's method). Isolates belonged to two different periods. Group A contained strains isolated in 1987-1988 and group B contained strains which were isolated in 1998-2000. A variety of serotypes was found. Serotype HS:2 was predominant, followed by the HS:4 complex and HS:1,44. Many clinically important Guillain-Barré Syndrome associated serotypes--like HS:19--were identified. There were no significant differences in the distribution of serotypes between the two periods. The present report provides reference data, as this is the first C. jejuni serotyping study ever made in Greece.

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BACKGROUND: During the course of multiple sclerosis (MS) intrathecal oligoclonal IgGs are present in the cerebrospinal fluid (CSF). The intracellular human pathogen Chlamydia pneumoniae may play a role either as a causative pathogenetic agent in the disease, or C. pneumoniae-infected MS patients could be immunologically less able to clear the agent from the central nervous system (CNS). METHODS: CSF samples were studied in 100 individuals -- 70 MS patients and 30 age-matched controls with other neurological diseases. CSF was taken by lumbal puncture; cell cultures were performed by the cell vial technique, followed by a 4-day incubation at 37 degrees C. A nested PCR was performed. RESULTS: C. pneumoniae was detectable in the CSF of only 2.9% of the MS patients and none of control patients (with no significant difference between the MS patients and controls). IgG antibodies were positive in only 1.43% of the MS patients and 3.33% of the controls. IgA antibodies were positive in 6.66% of the control patients and none of the patients were positive for IgM antibodies. There was no statistically significant difference between the two groups of patients with respect to the three antibody classes. CONCLUSIONS: The results confirm the high leave of controversy surrounding a possible link between C. pneumoniae and MS, and the matter requires further thorough investigation.

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BACKGROUND: Whipple's disease (WD) is a rare multisystemic bacterial infection, with variable clinical manifestations occasionally involving the central nervous system. As the cultivation of the etiologic agent, Tropheryma whippelii, is difficult, a laboratory diagnosis is usually based on histological methods. In the last few years, molecular detection of the bacterial 16SrRNA genes by PCR, with 2 primer sets, has greatly contributed to the ability of clinicians to diagnose this disease. We present a cerebral case of WD in a 48-year-old male, successfully diagnosed using PCR with T. whippelii in the blood and feces. As far as we know this is the first case reported from Greece. METHODS: For the diagnosis of WD, histological examination of duodenum biopsy for diastase-resistant, non-acid fast, periodic acid Schiff (PAS)-positive inclusions in macrophages, and molecular detection of the 16SrRNA genes of T. whippelii by PCR in cerebrospinal fluid, blood, and feces, were performed. RESULTS: The histological detection was negative. PCR results were positive in the blood and feces of the patient and negative in the cerebrospinal fluid. Seven months after the onset of antimicrobial therapy, PCR was negative in all three clinical specimens. CONCLUSIONS: The application of PCR proved to be an invaluable tool for the recognition, differential diagnosis and early initiation of antimicrobial therapy for the patient diagnosed with WD, a disease which is generally fatal if it remains untreated.

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